U.S. patent application number 12/947125 was filed with the patent office on 2011-03-24 for method and device for the assessment of fluid collection networks.
Invention is credited to David J. Saylor.
Application Number | 20110071773 12/947125 |
Document ID | / |
Family ID | 40564332 |
Filed Date | 2011-03-24 |
United States Patent
Application |
20110071773 |
Kind Code |
A1 |
Saylor; David J. |
March 24, 2011 |
Method and Device for the Assessment of Fluid Collection
Networks
Abstract
An improved method for monitor a fluid collection network is
disclosure. The improved method includes installing several
monitoring devices into sewer system manholes, recording fluid
level and flow, reading the recorded data, and displaying the data
in chart or map form. Data may be displayed in two or three
dimensional maps that may be overlaid with information of
topography, street maps, and single or multiple sewer systems. Data
displayed on the maps may include fluid flow rates, fluid levels,
derivatives and integrals of flow rates, and differences in fluid
levels or flow between monitoring devices.
Inventors: |
Saylor; David J.;
(Westville, IN) |
Family ID: |
40564332 |
Appl. No.: |
12/947125 |
Filed: |
November 16, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12257311 |
Oct 23, 2008 |
7836760 |
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12947125 |
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Current U.S.
Class: |
702/45 ;
703/1 |
Current CPC
Class: |
G01F 23/00 20130101;
G01D 9/005 20130101; G01F 1/32 20130101; G01F 1/68 20130101; G01F
1/20 20130101; G01F 15/063 20130101; G01F 1/684 20130101; G01F
15/0755 20130101; G01D 21/00 20130101 |
Class at
Publication: |
702/45 ;
703/1 |
International
Class: |
G06F 19/00 20110101
G06F019/00; G01F 1/00 20060101 G01F001/00; G06F 17/50 20060101
G06F017/50; G06G 7/50 20060101 G06G007/50 |
Claims
1. A sewer analysis computer system for displaying fluid flow
information relating to and facilitating removal of obstructions in
a municipal sewer system having fluids traveling through a
plurality of pipes and a plurality of manhole access points to the
pipes, the computer system programmed to: receive a plurality of
first values from a plurality of measurements of a plurality of
fluid flows through a portion of the plurality of pipes near a
first set of the plurality of manhole access points during a first
time interval; simultaneously display the plurality of first values
with a plurality of animated ribbons sequentially illustrating a
time range less than the first time interval, wherein each animated
ribbon simultaneously displays at least three measurements at
unique times in a single pipe of the municipal sewer system; and
indicate a first obstruction in the municipal sewer in response to
the first values from a first of the plurality of pipes increasing
in response to a rain event before the average of the plurality of
first values.
2. The sewer analysis computer system of claim 1 further programmed
to: receive a plurality of second values representative of a second
portion of the plurality of flows through the plurality of pipes
for a second time interval at a second set of the plurality of
access points to the plurality of pipes, the plurality of second
locations selected based upon problem indicia in the plurality of
first values.
3. The sewer analysis computer system of claim 2 wherein the second
set of the plurality of access points to the plurality of pipes are
clustered around the first obstruction.
4. The sewer analysis computer system of claim 2 wherein the first
set of the plurality of manhole access points includes more than 5%
of all of the manhole access points in the municipal sewer
system.
5. The sewer analysis computer system of claim 2 wherein the first
time interval is at least 30 days.
6. The sewer analysis computer system of claim 1 wherein the
plurality of animated ribbons are displayed on a three dimensional
chart, the three dimensional chart having the plurality first
values displayed on a vertical/z-axis, the first time range
displayed on a perspective/y-axis, and the plurality of animated
ribbons dispersed according to the first locations along a
horizontal/x-axis.
7. The sewer analysis computer system of claim 1 wherein the first
values include a first set of acceleration values and a first set
of pressure values.
8. The sewer analysis computer system of claim 7 further comprising
a first of the plurality of animated ribbons only illustrating the
first set of acceleration values, and a second of the plurality of
animated ribbons only illustrating the first set of pressure
values.
9. The sewer analysis computer system of claim 8 wherein the
plurality of animated ribbons are displayed on a three dimensional
chart, the three dimensional chart having the plurality first
values displayed on a vertical/z-axis, the first time range
displayed on a perspective/y-axis, and the plurality of animated
ribbons dispersed according to the first locations along a
horizontal/x-axis; and the first of the plurality of animated
ribbons is offset from the second of the plurality of animated
ribbons along the vertical/z-axis.
10. The sewer analysis computer system of claim 1 further
programmed to: simultaneously display a line chart with the
plurality of animated ribbons, wherein the line chart includes a
highlighted region representative of the time range shown by the
plurality of animated ribbons.
11. The sewer analysis computer system of claim 10 further
programmed to: receive a user selection of particular location on
the line chart and update the time range in response to the user
selection.
12. The sewer analysis computer system of claim 10 further
programmed to indicate a second obstruction in the municipal sewer
in response to the first values from a second of the plurality of
pipes remaining elevated after the rain relative to the average of
the plurality of first values.
13. The sewer analysis computer system of claim 1 further
programmed to compile an information set from a topographic map and
a sewer map; and designate the plurality of first locations using
the information set.
14. The sewer analysis computer system of claim 1 wherein the
plurality of first values are substantially time synchronized.
15. The sewer analysis computer system of claim 1 further
programmed to normalize the first values for each of the plurality
of pipes in the municipal sewer system.
16. The sewer analysis computer system of claim 1 wherein the
plurality of animated ribbons are area filled three dimensional
animated ribbons displayed on a three dimensional map, the
plurality of area filled three dimensional animated ribbons having
the first values displayed on a height/z-axis and time displayed on
a perspective axis; and the area filled three dimensional animated
ribbons positioned on the three dimensional map at a plurality of
positions representing the first locations.
17. A computer system for identifying a location of restriction,
infiltration, and/or inflow of storm water runoff into a sewer
system covering a specified area, the computer system configured
to: receive a topographical map of the specified area; convert the
topographical map to a three dimensional image of the specified
area; analyze the three dimensional image to predict an area of
storm water runoff or collection during wet weather; receive a map
of the sewer system; overlay an image of the map of the sewer
system on the three dimensional image; identify a portion of the
sewer system located at the area of storm water runoff or
collection during wet weather and identify the location of
potential infiltration and inflow of storm water runoff into the
sewer system during wet weather; receive a depth of flow
measurement from the location for a time interval; and illustrate
the depth of flow measurement at the location as an animated ribbon
sequentially showing a time range less than the time interval, the
animated ribbon displayed on a three dimensional chart having the
depth of flow displayed on a vertical/z-axis, time displayed on a
perspective/y-axis.
18. A method of evaluating a gravity-type flow conveyance system
having a known geometry, the method comprising the steps of:
identifying a plurality of access points in the hydraulic
conveyance system; identifying sources of flow input to the system
upstream of each access point identified; measuring a depth of flow
at each access point for a time interval; illustrating the depth of
flow at each access point as an animated ribbon sequentially
showing the depth of flow for a time range less than the time
interval, the animated ribbons displayed on a three dimensional
chart having the depth of flow displayed on a vertical/z-axis, time
displayed on a perspective/y-axis, and uniquely identified data
from the plurality of access points displayed along a
horizontal/x-axis; and comparing the animated ribbons to evaluate
whether flow restrictions may exist in the conveyance system.
19. The method of claim 18 further including the step of
prioritizing maintenance on the system based on the comparison of
animated ribbons.
20. The method of claim 18 further including the step of inspecting
portions of the system for restrictions based on the comparison of
animated ribbons; and measuring a flow at a location based on the
comparison of animated ribbons.
Description
CROSS-REFERENCE TO COPENDING APPLICATION
[0001] This application is a divisional of U.S. patent application
Ser. No. 12/257,311 entitled "Method and Device for the Assessment
of Fluid Collection Networks" by David J. Saylor filed on Oct. 23,
2008 that issued as U.S. Pat. No. 7,836,760 and claims the benefit
of U.S. Provisional Patent Application Ser. No. 61/000,050,
entitled "Method and Device for the Assessment of Fluid Collection
Networks" filed Oct. 23, 2007, the contents of which are all herein
incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to a device and
method for testing flow rates in a liquid system, and more
particularly to a device and method for continuously monitoring
flow rates in a sewer system.
BACKGROUND OF THE INVENTION
[0003] To prevent water pollution in furtherance of the goals of
the Clean Water Act, regulations and enforcement actions have
historically focused on the output of wastewater treatment
facilities. However, in recent years, the technology for treating
wastewater has largely matured to the point that treatment
facilities are decreasingly the source of significant water
pollution. To further eliminate potential water pollution, the
United States Environmental Protection Agency, municipalities, and
sanitary sewer system authorities have recently refocused their
attention and resources on the networks of pipes that transport
wastewater to the treatment facility.
[0004] These piping networks may be constructed as a combined
wastewater and storm water system, or be dedicated exclusively to
the transport of wastewater. In either case, untreated wastewater
can overflow from the system into the environment. For the health
of the community and environment, and to remain in compliance with
the law, a sanitary sewer system authority must prevent such
overflows. To comply with a permit to operate a sanitary sewer
system, a sewer authority must "take all reasonable steps to
minimize or prevent any discharge . . . which has a reasonable
likelihood of adversely affecting human health or the environment."
40 CFR 122.41(d).
[0005] A sanitary system overflow (SSO), can be caused by a number
of factors. The primary causes are restrictions and blockages in
the sewer system, most often caused by the accumulation of debris,
roots and/or grease in a sewer pipe. In wet weather conditions,
storm water runoff may overwhelm the capacity of a combined
sanitary sewer and storm water system, and cause the system to
overflow.
[0006] In the past, municipalities and sanitary system authorities
have addressed actual and potential sanitary sewer system overflows
in a number of ways. Many authorities have simply built additional
or redundant capacity into their piping systems to prevent
overflows. Studies have shown, however, that restrictions and
blockages are the primary causes of overflows, not a lack of
capacity in the system. Thus, simply adding additional capacity
leads to piping systems that are underutilized and more expensive
than necessary to serve the sanitary needs of the community.
[0007] The infiltration and inflow of storm water into a dedicated
sanitary sewer system is a significant concern. During wet weather
conditions, storm water runoff may infiltrate a dedicated sanitary
sewer system. Even if the infiltration does not lead to a system
overflow, infiltration and inflow of storm water into a sanitary
sewer system leads to increased costs because the storm water
inflow must then be treated along with the untreated sewage.
[0008] Restrictions, infiltrations and inflows lead to increased
costs and potential environmental problems, and an SSO may result
in untreated sewage being released into the environment or backing
up into residential basements. To avoid these problems,
municipalities and sanitary sewer system authorities attempt to
identify potential points of restriction, infiltration, and inflow
in a sanitary sewer system and address any problems causing the
infiltration and inflow.
[0009] Storm water runoff may infiltrate a dedicated sanitary sewer
system through broken or ruptured pipes. However, because these
pipes are typically underground, the infiltration point is
difficult if not impossible to locate and detect by visual
inspection during a wet weather event. Although the location of an
overflow may be obvious, the source of the extra water that is
actually causing the overflow may be a mystery. Also, in most
cases, the only evidence of infiltration is the increased burden on
treatment facilities during a wet weather event.
[0010] To detect and identify infiltration points, municipalities
and sanitary sewer system authorities typically monitor the flow in
the system during a wet weather event. Flow measurements may be
taken at a multitude of points in the system. These flow
measurements may then be compared with flow measurements during dry
weather to determine if the wet weather has increased flow at a
particular point or points in the system. Such flow measurement
studies, however, are difficult and expensive to administer, in
addition to being difficult to schedule due to the unpredictability
of the weather.
[0011] Some larger authorities have employed complex and expensive
evaluation methods to identify potential causes of sewer
infiltration and SSO's. These methods often include the use of
expensive devices for monitoring flow at different points in the
system and the employment of personnel and/or consultants to
collect and analyze data from the flow monitoring devices. The data
is often analyzed by consultants using proprietary software by paid
consultants.
[0012] Many devices for measuring and monitoring fluid flow
velocity have been developed. The velocity of some fluid flows may
be measured by placing a paddle wheel or turbine in the flow and
measuring the rate of spin of the device. Fluid flow velocity may
also be measured by placing a bending vane type sensor in the flow
and measuring the deflection of the vane or by placing a
restriction on the flow and measuring the differential pressure of
the restricted flow. Although inexpensive compared to other
measurement techniques, these types of devices necessarily obstruct
the fluid flow. In addition, these types of devices are not well
suited for certain applications because the measurement device
cannot be easily inserted and secured in the fluid flow.
[0013] More advanced measurement devices that do not obstruct fluid
flow include ultrasonic and magnetic flow meters. Although more
precise and reliable, these types of devices are typically very
expensive, limiting their application. Also, due to limitations of
the technology, these devices are often not well suited for
measuring irregular flows that may include solids. These types of
flow meters are also disadvantageous for many applications because
they are difficult to install, calibrate, and operate.
[0014] Another type of flow measurement device is based on the
known principal that vortices are created on the downstream side of
an object when fluid flows past the object. If the object is
allowed to move, these vortices will cause the object to oscillate
periodically in the fluid flow. An example of this common
phenomenon is a flag flapping in the wind. To measure flow velocity
using this principal, an object is inserted in a fluid flow and
allowed to oscillate. As the velocity of flow increases, the
frequency of oscillation increases in relation to the flow. By
measuring the frequency of oscillations of the object in the fluid
flow, the velocity of the fluid flow may be determined.
[0015] A flow meter that utilized this phenomenon is disclosed in
U.S. Pat. No. 2,809,520 issued to Richard, where an elongated
sensing element is placed in a fluid flow, causing the sensor to
oscillate. The mechanical oscillations of the sensor are converted
to an electrical signal using different types of transducers
including a piezoelectric crystal, electrical contacts and a
condenser plate. The frequency of the electrical signal can then be
read on a frequency meter and used to determine the velocity of the
fluid flow.
[0016] An accelerometer is another device for measuring
oscillations. Accelerometers can also measure acceleration, detect
and measure vibrations, or measure inclination. Accelerometers
sometimes consist of little more than a suspended cantilever beam
or mass with a deflection sensor. A range of accelerometers are
available to detect a magnitude of accelerations. Single axis, dual
axis, and three axis accelerometers are available. Accelerometers
have been used to measure the vibration of cars, machines,
buildings, and the earth itself. Accelerometers have been
incorporated into media players and handheld gaming devices such as
Apple's iPhone.TM. and Nintendo's Wii.TM. controller.
[0017] The vortices caused by an object in a fluid flow may also be
detected and measured to determine flow velocity. A flow meter
utilizing this technique is disclosed in U.S. Pat. No. 3,948,098
issued to Richardson, where a plate is placed in a flowing fluid
and a piezo-electric element senses changes in pressure caused by
the vortices shed from the plate. The piezo-electric element
generates an alternating voltage at a frequency that corresponds to
the vortex pressure pulses and the flow rate of the fluid.
[0018] Although these and other devices have been developed that
measure fluid flow based on the measurement of vortices or the
oscillation of an object in a fluid flow, such fluid flow
measurement technique has not seen widespread application. Those of
ordinary skill in the sewage flow measurement art have instead
focused on other technologies when developing sewage flow
measurement devices. As a result, there is a need for improvement
in the field of sewage flow measurement.
[0019] Specifically, many conventional sewage flow meters and
associated techniques are often beyond the financial capacity and
skill set of small and medium sized sanitary system authorities.
Also, because of the cost and complexity of these evaluation
methods, a complete review of the entire sanitary system is
typically not performed by sanitary system authorities capable of
affording such techniques and software. Thus, although general
problem areas in the system may be identified, specific pipe
restrictions and blockages may be missed.
[0020] Due to the cost of employing data collection personnel and
consultants, the review and analysis of most sanitary sewer systems
is typically short lived, and usually only performed in response to
a specific problem or overflow. Prior art evaluation techniques are
typically project-based, specific to a particular problem and not
designed for ongoing assessment of the collection network. The
resultant data is typically not incorporated into the ongoing
operation and maintenance procedures of the authority, and is
therefore not helpful in identifying and solving future problems in
the system.
[0021] Moreover, flow measurement studies are merely the first step
in addressing an infiltration and inflow problem. After the study
has been conducted, the potential problem areas identified must be
further evaluated and inspected to determine if infiltration is
actually occurring, how it is occurring and how it may be
addressed. This inspection may require actual physical examination
of the piping by personnel and/or inspection of the piping with
cameras and closed circuit television (CCTV). This critical next
step can be expensive and difficult to conduct.
[0022] The value of any flow measurement study depends on its
ability to accurately predict the precise portion of the system
where infiltration and inflow may be occurring. If the study merely
identifies large portions of the system that have infiltration, the
study is essentially useless because these large portions must
still be inspected.
[0023] Those of skill in the art have developed complex
methodologies and expensive solutions to provide greater precision
in identifying the potential location of infiltration and inflow.
Some advocate increasing the flow detection points during a wet
weather study to more accurately identify the portions of the
system experiencing infiltration and inflow. Although this solution
may be cost effective because it decreases the cost of the next
step in the process, this solution is nonetheless very expensive
and beyond the financial capabilities of many small and medium
sized sanitary sewer system authorities. Sewage flow measurement
devices are expensive, and the additional personnel required to
monitor and measure additional points in the system also increases
the expense of the sewage flow measurement study.
[0024] Others have developed complex sewer system modeling
techniques and software for evaluating the performance of a system
and predicting the effect of inflow and infiltration during a wet
weather event. These techniques often require extended on-sight
evaluations by consultants, which further increases the cost. Thus,
there is a need for accurately and economically pinpointing the
source of infiltration and inflow into a sanitary sewer system,
whereby managers and owners of such systems may conduct sewage flow
measurement studies that accurately predict where infiltration and
inflow are occurring.
[0025] Because the evaluation of sanitary sewer systems has
historically been project-based and in response to a specific
problem or overflow, little attention has been paid to the ongoing
maintenance and upkeep of the system. However, sewer system assets
that are not regularly maintained deteriorate faster, leading to
higher replacement and emergency response costs. When a sewer
system is regularly maintained, its lifetime can be increased and
maintenance costs distributed over the lifetime of the system.
Thus, a regular evaluation and maintenance program will save money
in the long run, avoid unexpected and unplanned costs, and
safeguard against the health risks associated with SSO's.
[0026] Accordingly, an object of the present invention is to
provide an evaluation device and method for identifying potential
causes of sanitary system overflows including restrictions and
blockages in the piping system, ruptured or deteriorated pipes and
sources of storm water inflow and infiltration into the system.
[0027] Another object of the present invention is to provide a
method and device for measuring fluid flow in a sewage system based
on the oscillations, tilt, and pressure exerted upon of an object
in the sewage fluid flow.
[0028] A further object of the present invention is to provide an
evaluation device and method that specifically identify problem
points in the sewage collection network and avoid the need to build
additional or redundant capacity in the sewage system.
[0029] Yet another object of the present invention is to provide a
flow measurement device and that is inexpensive to administer,
simple to use, does not significantly obstruct fluid flow, and is
easily inserted into the fluid flow to obtain a measurement.
[0030] Another object of the present invention is to provide an
evaluation method that can be incorporated as part of an ongoing
sewer system maintenance and upkeep program to prolong the life of
the system and avoid unexpected costs.
[0031] Another object of the present invention is to provide an
evaluation method that reduces the cost of conducting an
infiltration and inflow study by minimizing the time that
consultants and engineers must be on-sight to evaluate the
system.
[0032] A still further object of the present invention is to
provide an evaluation method that utilizes available data and
technology not previously available for the analysis of sanitary
sewer systems.
[0033] Finally, another object of the present invention is to
provide evaluation methods that more efficiently predict the
location of infiltration and inflow when compared to conventional
sewage flow analysis methods.
SUMMARY OF THE INVENTION
[0034] An improved device and method for analyzing sewer systems
maintains the benefits of traditional sewer analysis systems, while
achieving the important objective of providing a low cost, simple,
and easy to use device and method for monitoring fluid level and
flow rates at multiple locations in a sewer system.
[0035] A sewage flow monitoring device according to present
invention comprises a data acquisition device with an accelerometer
inside a bendable tube. One end of the bendable tube is connected
to a pole while the other end is submerged in a fluid flow. The top
of the pole may be connected to an expansion device secured near
the top of a sewer manhole. The tilt, oscillation, and pressure
exerted upon the tube due to sewage fluid flow rate are measured by
the accelerometer and a pressure monitor.
[0036] A method according to the present invention comprises
installing several monitoring devices into sewer system manholes,
recording fluid level and flow with accelerometers and pressure
monitors, reading the recorded data, and displaying the data in
chart or map form. Data displayed in map form may show topography,
street maps, and single or multiple sewer systems. The maps may be
created may in two or three dimensional. Data displayed on the maps
may include fluid flow rates, fluid levels, derivatives and
integrals of flow rates, and differences in fluid levels or flow
between monitoring devices.
[0037] A low usage cost of sewage flow and level measuring and
monitoring device according to the invention is thereby achieved by
a low cost of accelerometers and pressure sensors, a small size and
weight of the monitoring device, an easy replacement of components,
and by ease of installing such device into a sewer system manhole.
The device and method also improve safety compared with
conventional method because personnel are not required to enter the
manhole during installation of device. Additionally, in one
variation, the pole that supports the bendable tube may be formed
to be collapsible or segmented to decrease the space required for
storage or transport of the device of the present invention.
[0038] The foregoing summary does not limit the invention, which is
defined by the attached claims. Similarly, neither the Title nor
the Abstract is to be taken as limiting in any way the scope of the
disclosed invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Each of the drawing figures now described shows an exemplary
embodiment of the present invention.
[0040] FIG. 1 is a perspective view of the monitoring device of the
present invention installed in a manhole to monitor the flow in a
sewer pipe.
[0041] FIG. 2 is a partial side view of a monitoring device with a
flow meter in a low fluid level.
[0042] FIG. 3 is a partial side view of a monitoring device curved
due to a moderate fluid level flow.
[0043] FIG. 4 is a partial side view of a monitoring device with a
highly curved flow meter in a high fluid level.
[0044] FIG. 5 is a partial side view of the bottom end of a flow
meter.
[0045] FIG. 6 is a partial cross section side view of the bottom
end of a flow meter showing a data acquisition compartment and an
end cap.
[0046] FIG. 7 is a partial cross section side view of the bottom
end of a flow meter without an end cap.
[0047] FIG. 8 is a top-side perspective view of a data acquisition
device without a protective compartment casing.
[0048] FIG. 9 is a bottom-side perspective view of a data
acquisition device without protective compartment casings.
[0049] FIG. 10 is a top view of a data acquisition device without
protective compartment casings.
[0050] FIG. 11 is a bottom view of a data acquisition device
without a rear compartment casing.
[0051] FIG. 12 is a side view of a data acquisition device with a
battery between a pressure tube and an electronics assembly.
[0052] FIG. 13 is a partial cross sectional view of a data
acquisition device showing a pressure sensor and a pressure tube
filled with a hydrophobic material.
[0053] FIG. 14A is a side perspective view of a data acquisition
device with a front and rear compartment casing.
[0054] FIG. 14B is a side perspective view of a data acquisition
device with a exterior support tube around the rear compartment
casing.
[0055] FIG. 15 is a perspective view of a data acquisition device
with front and rear compartment casings that enclose the
electronics and inductively chargeable battery of the data
acquisition device.
[0056] FIG. 16 is a perspective view of a data acquisition device
with a translucent rear compartment casing and a front compartment
casing that completely enclose the electronics and inductively
chargeable battery of the data acquisition device.
[0057] FIG. 17 is a perspective view of a data acquisition device
having a translucent rear compartment casing and a linear
generator.
[0058] FIG. 18 is a partial perspective view of a data acquisition
device having a linear generator.
[0059] FIG. 19 is a partial cross sectional view a flow meter end
section showing a knobbed end and a pressure line.
[0060] FIG. 20 is a partial view of a flow meter end section
showing a tapered end.
[0061] FIG. 21 is a partial view of a flow meter end section
showing a tapered end with tongs to prevent the pressure line from
contacting the wall of a sewer.
[0062] FIG. 22 is a partial view of a flow meter end section
showing a rounded end.
[0063] FIG. 23 is a side view of a flow meter.
[0064] FIG. 24 is a side view of a flow meter with a bellowed lower
section.
[0065] FIG. 25 is a side view of a flow meter with bellowed upper
and lower sections.
[0066] FIG. 26 is a side view of a flow meter with a non-smooth end
section.
[0067] FIG. 27 is a side view of a flow meter with two end
sections.
[0068] FIG. 28 is a side view of a flow meter with a tapered
midsection.
[0069] FIG. 29 is a top cross-sectional view of a flow meter with a
square top section and a round midsection.
[0070] FIG. 30 is a side view of a flow meter with a square top
section and a round midsection.
[0071] FIG. 31 is a side view of a flow meter with a rounded
end.
[0072] FIG. 32 is a top view of a flow meter with a flared
section.
[0073] FIG. 33 is a sectional view of a flow meter with a weighted
data acquisition device and two other weighted sections.
[0074] FIG. 34 is a sectional view of a flow meter with three
weighted sections.
[0075] FIG. 35 is a sectional view of a flow meter with one
weighted section.
[0076] FIG. 36 is a perspective view of a monitoring device
comprising an expansion device with three contact points, a weight
supported by a cable, and a flow meter.
[0077] FIG. 37 is a top perspective view of a monitoring device
with an expansion device secured near the top of a manhole and a
flow meter that is not substantially parallel to the sewer
flow.
[0078] FIG. 38 is a top perspective view of a monitoring device
with an expansion device secured at two locations near the top of a
manhole and a flow meter that is substantially parallel the sewer
flow.
[0079] FIG. 39 is a perspective view of a monitoring device
comprising a catch lid connected to a flow meter and a pole, an
expansion device, and a spring connected to the pole and the
expansion device.
[0080] FIG. 40 is a perspective view of a monitoring device with a
spring and catch lid that substantially secure one end of the flow
meter to the top of a sewer pipe.
[0081] FIG. 41 is a partial cross-sectional side view of an
expansion device.
[0082] FIG. 42 is a partial cross-sectional side perspective view
of an expansion device that functions to secure the monitoring
device near the top of a manhole.
[0083] FIG. 43 is a perspective view of a monitoring device with an
expansion device selectively secured to a portion of a pole.
[0084] FIG. 44 is a partial perspective view of an expansion device
with a cushioned shaft cap.
[0085] FIG. 45 is a partial top view of an expansion device with a
cushioned shaft cap.
[0086] FIG. 46 is a partial perspective view of an expansion device
with a secondary screw-type positioning means.
[0087] FIG. 47 is a partial perspective view of an expansion device
with a secondary screw-type positioning means and a shaft cap that
is rotated about a pivot point.
[0088] FIG. 48 is a partial perspective view of an expansion device
with a secondary screw positioning means and a pivot point near the
shaft cap.
[0089] FIG. 49 is a partial top view of an expansion device with a
secondary screw positioning means and a shaft cap that is rotated
about a pivot point.
[0090] FIG. 50 is a perspective view of a monitoring device with an
expandable segmented pole connected to a flow monitor and an
expansion device.
[0091] FIG. 51 is a perspective view of a monitoring device with an
expansion device that has three portions for contacting near the
top of a manhole.
[0092] FIG. 52 is a perspective view of a monitoring device with an
expandable segmented pole that is supported by a manhole insert
with an outer lip having a diameter substantially similar to a
manhole cover.
[0093] FIG. 53 is a side view of a data acquisition device having a
plurality of heat sensors imbedded in the flexible tube.
[0094] FIG. 54 is a schematic of a sensor for measuring the flow
rate of a solution, the sensor having a heat source and a
temperature monitor.
[0095] FIG. 55 is a sample response curve of a temperature monitor
in a fast moving solution stream.
[0096] FIG. 56 is a sample response curve of a temperature monitor
in a slow moving solution stream.
[0097] FIG. 57 is a chart showing data collected from a data
acquisition device.
[0098] FIG. 58 is a street map showing the positioning of multiple
monitoring devices in a city sewer system.
[0099] FIG. 59 is a street map with a sewer overlay showing the
positioning of multiple monitoring devices in a city sewer
system.
[0100] FIG. 60 is a chart showing data collected from multiple
monitoring devices in a city sewer system.
[0101] FIG. 61 is a street map with a sewer overlay, a flow overlay
represented by numbers, and markers that show the positions of
multiple monitoring devices in a city sewer system.
[0102] FIG. 62 is a street map with a sewer overlay, a flow overlay
represented by symbols, and markers that show the positions of
multiple monitoring devices in a city sewer system.
[0103] FIG. 63 is a street map with a sewer overlay, a flow overlay
represented by textures between monitoring devices, and markers
that show the positions of multiple monitoring devices in a city
sewer system.
[0104] FIG. 64 is a street map with a sewer overlay and monitoring
device indicators that show the position and flow rate at multiple
monitoring devices.
[0105] FIG. 65 is a three dimensional map showing the topography of
a city, a street map, a sewer overlay, and the position of multiple
monitoring devices.
[0106] FIG. 66 is a street map with sanitary and storm sewer
overlays.
[0107] FIG. 67 is a three dimensional map showing the topography of
a sanitary sewer and a storm sewer along with the position of
multiple monitoring devices in each sewer.
[0108] FIG. 68 is a street map with a sanitary sewer overlay, flow
arrows indicating the directional flow of the sewer, and an
identified blockage in the sewer system.
[0109] FIG. 69 is an image of a data analysis tool illustrating the
street location of four flow monitors, a portion of the data
recorded by the flow monitors over a period of time illustrated as
ribbons, and a chart highlighting the portion of the data
illustrated by the ribbons.
[0110] FIG. 70 is an image of a data analysis tool indicating an
increase in flow at monitor C before an increase in flow at monitor
A, B, and D.
[0111] FIG. 71 is an image of a data analysis tool indicating an
increase in flow at monitor D before an increase in flow at monitor
A, B, and C.
[0112] FIG. 72 is an image of a data analysis tool illustrating the
street location of four flow monitors, a portion of the data
recorded by the flow monitors over a period of time illustrated as
a 3D area chart, and a chart highlighting the portion of the data
illustrated by the 3D area chart.
[0113] FIG. 73 is an image of a data analysis tool illustrating the
a portion of the data (z-axis) recorded by numerous monitors
(x-axis) over a period of time (y-axis) as a ribbons, and a chart
highlighting the portion of the data illustrated by the
ribbons.
[0114] FIG. 74 is an image of a data analysis tool illustrating the
a portion of the data (z-axis) recorded by numerous monitors
(y-axis) over a period of time (x-axis) as a ribbons, and a chart
highlighting the portion of the data illustrated by the
ribbons.
[0115] FIG. 75 is an image of a data analysis tool showing a
portion of the data recorded by four flow monitors over a period of
time illustrated as a 3D area chart and overlaid on a street map,
and a chart highlighting the portion of the data illustrated by the
3D area chart.
[0116] FIG. 76 is an image of a data analysis tool showing a
portion of the data recorded by four flow monitors indicating an
uneven flow rate at one of the monitors.
[0117] FIG. 77 is a flow diagram illustrating a process for
maintaining the integrity of a sewer system.
[0118] FIG. 78 shows a flow chart shows a flow chart for monitoring
and maintaining the integrity and operability of a sewer
system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0119] The present invention may be used with any type of fluid
collection network and is particularly suited for monitoring
sanitary and storm sewer systems. However, for descriptive
purposes, the present invention will be described in use with
sanitary and storm sewer systems.
[0120] FIG. 1 shows a perspective view of a monitoring device
comprising a securing mechanism in the form of an expansion device
10 contacting near the top of a manhole 15, a vertically oriented
spanning mechanism in the form of a pole 20 attached to the
expansion device and substantially spanning the height of the
manhole, and a flow meter 25 in the sewer flow 30 moving in a flow
direction 31 inside of a sewer pipe 35. The flow meter 25 has a
data acquisition device with an accelerometer and pressure monitor
that records the inclination, oscillations, and pressure exerted
upon the flow meter. The segmented pole 20 is adjustable so that
the flow meter 25 may be positioned above the sewer pipe bottom,
while still in the sewer flow. The length of the pole is
substantially dependant on the height of the manhole 15. The
expansion device is not positioned at the absolute top of the
manhole so that a manhole cover (not shown) may be placed over the
manhole while the monitoring device is installed. The manhole
illustrated is part of a municipal sewer collection network and has
a vertical housing embedded below a ground level, a fluid entrance
opening in the vertical housing, a fluid exit opening in the
vertical housing, and a round horizontal access opening above the
fluid entrance opening and the fluid exit opening, the round
horizontal access opening having a diameter greater than 2
feet.
[0121] In the preferred embodiment of the invention the expansion
device, pole, and flow meter are constructed from a variety of
robust materials such as metals or high strength polymers. While
the pole and expansion device are constructed primarily from rigid
materials, the flow meter is more flexible so that it bends due to
the sewer flow. The flow meter may include portions that are
constructed from vulcanized rubber, synthetic rubber, metals, or
polymers. The use of other materials will be obvious to those of
reasonable skill in the art and is within the scope of the
invention. Because the monitoring device, and especially the flow
meter will be exposed to wet conditions, materials used in the
construction of the monitoring device may be coated or water
proofed. Such coatings and treatments include galvanization,
polymer coatings, wax coatings, and paint.
[0122] FIGS. 2, 3, and 4 show a flow meter 25 in a low sewer flow,
a moderate sewer flow, and a high sewer flow, respectively. In the
low sewer flow, the flow meter is somewhat bent, and the water
pressure exerted on the flow meter is minimal. In the moderate
sewer flow, the flow meter is more curved as a result of the flow
direction 31. The increased fluid level further increases the
pressure exerted upon the flow meter. In a high sewer flow, the
flow meter is highly curved, oscillating, and there is a
substantial amount of fluid pressing down upon the flow meter. In
addition to providing a measurable action, the lateral oscillations
of the flow meter act to clear debris that may contact the flow
meter.
[0123] FIGS. 5 and 6 show a flow meter 25 having an threaded end
cap 40 connected to the main tube 45 of the flow meter. In the
preferred embodiment of the invention, the end cap is secured to
the main tube by threading 50. The end cap may also have a pressure
hole or orifice distance from the threading. The data acquisition
device 55 shown in FIG. 6 is easily removed from the hollow cavity
of the main tube of the flow meter when the end cap is unscrewed
from the main tube. The data acquisition device has a pressure tube
60 that connects to an end cap opening 65. The end caps shown in
FIGS. 5 and 6 have knobbed tips 70 that may be reinforced to
withstand continual rubbing against sewer pipes and debris. FIG. 7
illustrates the placement of the data acquisition device inside of
the main tube of the flow meter. The hollow portion of the main
tube may extend from the mobile end of the tube to the stationary
end, or the hollow portion may be specifically shaped to length of
the data acquisition device.
[0124] FIGS. 8-12 show a data acquisition device 55 without a
compartment casing. The data acquisition device comprises a
pressure tube 60 filled with a hydrophobic material, a pressure
sensor 75 that measures the pressure against the flow meter, at
least one accelerometer 80 that measures both the motion and
curvature of the flow meter, a radio transceiver device 85 for
transmitting information from the data acquisition device 55 to an
external data collection means, computer memory 90 for storing the
information gathered by the data acquisition device, a central
processing unit 95 on a printed circuit board 100 for controlling
the data acquisition device, a battery 105 that provides power to
the data acquisition device, and a battery securing means 110 that
secures the battery to the rest of the data acquisition device. The
pressure sensor 75 produces an electrical pressure signal that is
received by a data storage device such as computer memory on the
data acquisition device. The data storage device also receives and
records the tilt signal generated by the accelerometer. The battery
may also be positioned between the pressure tube and electronics as
shown in FIG. 12. A thin wire sheet 112 may be used to connect the
electronics to the pressure tube. In addition to, or instead of a
radio transceiver, other data transmission mechanisms may be
utilized. For example, data transmission wiring could be threaded
through a hollow cavity in the flexible tube that extends from the
mobile end to the stationary end. The data transmission wire could
further pass through a hollow portion of the pole.
[0125] When the accelerometers 80 are oscillated or tilted, an
electric response/tilt signal is generated that is dependant on the
oscillation and/or tilt. Because of their extreme sensitivity and
wide dynamic range, accelerometers have found application as
sensing devices that may be used in a variety of applications such
as video game controllers. Because of their robustness,
accelerometers are also well-suited for measuring and detecting
changes in fluid flow velocity. Flow meters with accelerometers may
be inserted in a fluid flow and allowed to oscillate in the flow.
As shown in FIG. 1, the flow meter is secured at one end to the
monitoring device pole. As the fluid flows past the flow meter, the
free end of the flow meter will bend and oscillate in the fluid, as
represented in FIGS. 2, 3, and 4.
[0126] There are many types of accelerometers that may be used in
the present invention such as a piezo-film, piezoelectric sensor,
shear mode, surface micro-machined capacitive, thermal, capacitive
spring mass based, electromechanical servo, null-balance, strain
gauge, resonance, magnetic induction, optical, surface acoustic
wave, laser, DC response, high temperature, low frequency, high
gravity, triaxial, modally tuned impact hammers, or seat pad
accelerometer. The use of other types of accelerometers will be
obvious to those of reasonable skill in the art and is within the
scope of the invention.
[0127] The inclination and oscillations of the flow meter will
produce an output signal from the accelerometer(s) in the data
acquisition device. When the fluid flow velocity increases, the
flow meter inclination and oscillations also increase, generating a
proportional change in the signal generated by the accelerometer(s)
of the data acquisition device.
[0128] FIG. 13 shows a cross section of a partial view of a
pressure tube 60 filled with a hydrophobic fluid 115. The
hydrophobic fluid may be any substance that is non-polar and liquid
at room temperature; however in the preferred embodiment of the
invention, the hydrophobic substance is an oil. The pressure tube
may be any length, although the preferred length is less than 10
centimeters in order to reduce the effects tube expansion. The
pressure sensor may be a fiber optic sensor, a mechanical
deflection sensor, a strain gauge sensor, a semiconductor
piezoresistive sensor, a microelectromechanical systems sensor, a
vibrating element sensor, or a variable capacitance sensor. Other
kinds of pressure sensors will be obvious to those of reasonable
skill in the art and are within the scope of the invention.
[0129] During a "rain event," the fluid depth inside of the storm
sewer will increase along with fluid flow velocity. A rain event
includes rain, sleet, melting snow, melting ice, and other events
that cause the flow rate through a collection network to deviate
from a standard amount. The increases in fluid pressure (.about.1
atm per 33 feet fluid) results in the hydrophobic fluid exerting
greater forces against the pressure sensor which are recorded by
the data acquisition device. Measurement of tilt and pressure are
beneficial for intermittent data acquisition because extended
sampling of the data is not required as it is with flow
measurements through oscillations. Extended data sampling typically
requires increased power consumption that decreases the expected
battery life of the device.
[0130] Signals from the accelerometers and pressure meter are
directed by to a central processing unit. The data from the central
processing unit is transferred to a storage device such as flash
memory or a magnetic hard drive. Upon request from an external data
reader, the stored data is transferred via a radio transceiver or
other wireless connection to the data reader. In an alternate
embodiment of the invention, a wired connection could be used to
transfer data to the data reader. Through empirical testing and
measurement of the signal delivered by fluid flows of known
velocity, a table of expected signals at certain fluid velocities
may be established. The monitoring device may then be used to
measure the velocity of a fluid flow under similar conditions.
[0131] The monitoring device may also be used to measure relative
changes in fluid flow velocity and depth regardless of whether an
actual velocity and depth are measured and recorded. To measure
relative changes in velocity and depth, the flow meter of the
measuring device is simply placed in a fluid flow and the output of
the signal monitored. If the fluid flow velocity and depth
increases, the signal from the accelerometer and pressure sensor
will change relative to the initial conditions. By comparing
relative changes instead of absolute changes, sewer pipes of varied
capacities may be easily compared. Additionally, the use of
relative change in flow rate/flow depth assists in comparing
locations with dissimilar rain levels (e.g. Seattle and Las
Vegas).
[0132] Although less precise than more developed technologies for
measuring fluid flow velocity, the present invention offers
significant cost savings over other technologies. Because
accelerometers and pressure sensors are relatively inexpensive,
they may be more widely deployed than more expensive flow
measurement devices. For example, the measurement device and method
may be inexpensively deployed throughout a sanitary sewer system to
monitor and measure fluid flow at multitudes of points in the
system for extended periods of time. This widespread deployment can
offer increased flow monitoring advantages and provide historical
flow data that could not be economically realized with more
expensive devices.
[0133] FIG. 14A shows a data acquisition device with a rear
compartment casing 120 interconnected with a front compartment
casing 125. The front compartment casing 120 has an orifice through
which the pressure tube 60 extends. In the preferred embodiment of
the invention, the rear compartment casing is made from a rigid and
robust plastic, while the front compartment casing is made from a
robust and flexible material such as rubber. The flexibility of the
front compartment casing allows it to form a watertight seal with
the main tube of the flow meter. The end cap further assists in
providing a watertight seal. The rigidity of the rear compartment
casing helps to protect the electronics of the data acquisition
device from objects that impact the flow meter. As shown in FIG.
14A, the pressure tube passes through a tube orifice in the front
face of the front compartment casing. Extending from the front face
is a cylindrical outer surface with a diameter greater than the
inner diameter of the flexible tube. The larger cylindrical portion
of the compartment limits how for into the flexible tube the data
acquisition device may be placed. Inside of the flexible tube, the
compartment has a cylindrical surface with a diameter similar to
the inner diameter of the flexible tube. The thinner cylindrical
surface of the compartment contacts the tube to form a
substantially watertight seal with the flexible tube.
[0134] FIG. 14B shows a data acquisition device that
enclosed/encapsulated within a plastic support tube 127. The
support tube/cylindrical waterproof compartment is shaped such that
in can be easily secured within a hollow cavity or core of the main
tube 45 of the device. The width of the tube is similar to the
diameter of the hollow cavity of the inner tube so that a tight
connection between the main tube and the support tube may be made.
Like the main tube, the support tube may have threading to secure
an end cap to the device. Alternatively, the support tube threading
may be in lieu of main tube threading. In hospitable environments,
the device may be used be used without the added protection of the
main tube.
[0135] FIGS. 15 and 16 show an alternate embodiment of the data
acquisition device with a continuous rear compartment 130 that
cooperates with a front compartment casing 125 to completely
enclose the data acquisition device. Completely enclosing the data
acquisition device reduces the likelihood of water damaging the
electronics of the data acquisition device. However, with the data
acquisition device completely sealed the battery is not as easily
replaceable as in the preferred embodiment of the invention. In
order to provide power to the data acquisition device, an
inductively chargeable battery 135 is sealed inside the rear
compartment casing. A radio transceiver data reader 140 may have an
inductive charging device 145 that charges the battery as the data
from the data acquisition device is read. Inductively chargeable
batteries are often used in situations where the batteries must be
completely sealed to avoid water damage, such as with electric
toothbrushes.
[0136] FIGS. 17 and 18 show a data acquisition device that has a
miniature linear generator 150 that provides additional power to
the data acquisition device. The linear generator has a coil of
conductive windings 155, a freely moveable permanent magnet 160,
and a track 165 on which the permanent magnet moves. As the data
acquisition device oscillates in the sewer flow, the permanent
magnet also oscillates back and forth within the conductive coils
producing an alternating voltage that may be used to power the data
acquisition device. The addition of a linear generator increases
the length of time that the monitoring device may be deployed and
reduces the long term costs associated with obtaining new batteries
and replacing the old batteries.
[0137] FIGS. 19-22 show various embodiments of the bottom end of
the flow meter. FIG. 19 shows a cross section of a tapered end cap
with a knobbed tip 70. The knobbed tip disrupts the fluid flow and
creates turbulent flow vortices. The turbulence of the solution
assists in oscillating the accelerometer in the data acquisition
device which improves the sensitivity of the device. FIG. 20 shows
a smooth tapered end cap 170. The absence of a knob reduces the
likelihood of flotsam in the sewer collecting on the flow meter.
FIG. 21 shows a tapered end cap with spacer tongs 175 that serve to
prevent the end of the tip from resting against the bottom of the
sewer pipe in low sewer flow conditions. Rubbing the opening of the
pressure tube 60 against the bottom of a sewer pipe may be
detrimental to pressure measurement. FIG. 22 shows a portion of a
flow meter with a round end cap 180. A round end cap decreases the
required length of the pressure line thereby decreasing
fluctuations in pressure readings associated with expansion or
contraction of the pressure tube.
[0138] FIGS. 23-35 show various embodiments of a flow meter
flexible shaft. FIG. 23 shows a flow meter with a smooth main
section 185, a tapered end, and a knobbed tip. The smooth main
section is easily manufactured, provides a substantially uniform
cross section, and reduces the number of points to which sewer
debris can attach. FIG. 24 shows a flexible shaft with a lower
bellowed main section 190. The bellows act to provide a region that
bends with less resistance than the rest of the main section so
that the flow meter oscillates and bends more during low sewer flow
conditions. An alternate embodiment is shown in FIG. 25 where the
main section of the flow meter has a lower bellowed section 190 and
an upper bellowed section 195. The upper and lower bellows may be
size selected to provide a desired non-linear response to an
increase in sewer flow rate.
[0139] FIG. 26 shows a flow meter with flexible shaft having a
roughened main section. The rough sections 200 may serve as a
visual indication of flow meter depth in sewer flow during the
installation of the device. FIG. 27 shows a flow meter with twin
end sections 205. Increasing the number of end sections and
associated data acquisition devices increases the robustness of the
system because the measuring device can still operate with one
malfunctioning data acquisition device. In addition to increasing
the robustness of the measuring device, interactions between with
the end sections to be measured as an additional way to monitor
sewer flow velocity and level. FIG. 28 shows a flow meter with a
tapered main section 210. The lesser thickness of the main section
decreases the flow meter rigidity increasing sensitivity to lower
sewer flow conditions.
[0140] FIGS. 29 and 30 show flow meters with rectangular upper main
sections 215. The rectangular sections serve to increase the
rigidity of the flow meter in certain locations, much like the
bellowed sections serve to decrease the rigidity of the flow meter.
FIG. 31 shows a flow meter with a rounded end cap. A rounded end
cap 180 allows the data acquisition device to be closer to the end
of flow such that the pressure line may be shorter in length. FIG.
32 shows a flow meter with a flared lower main section 220. The
flares increase the rigidity of the flow meter, while also
increasing the cross section that the flow meter presents to the
oncoming sewer flow. The increased cross section causes more force
to be exerted resulting in a greater flow meter bend.
[0141] FIGS. 33-35 show various cross sections of the flow meter
with weights 225 placed inside the flow meter. The weights decrease
the response of the flow meter at lower flow rates, but improve the
response linearity of the measuring device at higher flow rates. As
with the various features that may be included on the exterior of
the flow meter, the interior weights may be placed to achieve a
desired measurement response for a given flow rate.
[0142] FIG. 36 illustrates a measuring device that utilizes a cable
230 and a cable weight 235 to connect the flow meter to the
securing mechanism/expansion device. The use of a cable instead of
a rigid pole may reduce the amount of time it takes to install the
measuring device because the cable may be wound to the proper
position thus reducing the number of tools that must be used to
install the device.
[0143] FIGS. 37 and 38 illustrate the ability of the flow meter 25
flexible shaft to oscillate laterally or be moved by to the sewer
flow. In the illustrated embodiment of the invention, the pole
spanning the height of the manhole is substantially immobile
relative to the sewer fluid flow. In spanning the manhole, the pole
has a top portion near an manhole accessing opening of the sewer
collection network and a bottom portion secured to the anchored end
of the flexible shaft. The moveable end of the flexible shaft is
partially submerged in the fluid flow while the stationary end of
the shaft is anchored to the rigid pole. In addition to being a
measurable action, the oscillation of the flow meter helps to clear
off any sewer debris.
[0144] FIG. 39 shows an embodiment of a measuring device that has a
spring 240 and catch lid 245 connected to the pole. A hinged
connection is used between the pole and the securing
mechanism/expansion device so that the pole may be tilted based on
the forces acting upon it. When there are not significant external
forces, the spring pulls or pushes the poll away from a vertical
orientation. The angle of the pole may be such that the top of the
flow meter is in close proximity to the walls of the manhole. The
catch lid functions to catch on the top portion of a sewer pipe. By
standardizing the vertical position of flow meters, the measurement
variability of multiple flow meters may be reduced. FIG. 40 shows
an illustration of a measuring device with a spring and catch lid
securing the location of the top end of the flow meter. In the
illustration, the fastening mechanism is secured proximal to the
opening in the sewer collection network.
[0145] The segments of the pole may be connected together by a
securing means that does not require the use of external tools,
such as quick connects commonly used with garden hoses. If screw
threading is used to secure the segments of the pole, the poles may
have integral handles to act as leverage points when workers
tighten down the threads. Alternatively, a single non-segmented
pole may be used by trimming the pole to an appropriate length
during installation of the monitoring device.
[0146] FIGS. 41 and 42 show partial cross sections of securing
mechanism in the form of an expansion device 10 or fastening
mechanism with two post/shaft caps 250, an immobile post/shaft 255,
a mobile post/shaft 260, and a locking portion 265 adapted for
keeping the expansion device in an extended position for securing
the device to an manhole access opening and a retractable position
for removing the device from a municipal sewer collection network.
The immobile shaft is affixed to the locking portion, while the
mobile shaft is variably connected to the locking portion. The
mobile shaft includes a locking pin 270 that is capable of fitting
into a locking slot in the locking portion. The locking pin can be
compressed or removed in order to unlock the moveable shaft.
[0147] FIG. 43 shows a partial perspective view of an expansion
device/fastening mechanism with a rigid pole 20 variably connected
to a locking portion 265 by means of a clamping device 275. In the
preferred embodiment of the invention, the clamp includes a tension
knob 280 that is operable to selectively secure the pole to the
expansion device without the need for additional tools.
[0148] FIGS. 44 and 45 show perspective and top views,
respectively, of an alternate embodiment of an expansion device
shaft/pole/post cap. In the embodiment illustrated, a substantially
flexible section 285 such as a compressible cushion that is
compressible against a manhole wall, while a substantially rigid
section 290 acts to press the flexible section/compressible cushion
against a manhole wall. The rigid sections of an expansion device
are preferably constructed from metals or high strength polymers,
while the flexible sections are preferably constructed from natural
or synthetic rubber.
[0149] FIGS. 46-49 show partial views of an expansion device with a
secondary screw-type positioning means 295. Finer positioning of
the post/shaft cap is achievable with rotation of the screw than
with adjustment of the locking pins shown in FIGS. 40 and 41. In
the preferred embodiment of the invention, the course adjustments
to the expansion device are made with the locking pin, and fine
adjustments are made by rotating the screw. FIGS. 47-49 show an
expansion device with a rotation/pivot point 300 in close proximity
to the shaft cap. The pivot point aids in securing the device near
a manhole access opening by allowing the device to adapt to
irregular contours of the opening. The rotation of the shaft caps
allows the expansion device to better conform to any irregularities
in the curvature of a manhole opening.
[0150] FIG. 50 shows an isolated monitoring device with an
expansion device, a pole, and a flow meter. FIG. 51 shows an
isolated monitoring device with three shaft caps and a split
immobile shaft/post. The split shaft 305 and the double shaft caps
310 assist in securing the measuring device to the manhole. FIG. 52
shows an alternate embodiment of a measuring device where a lipped
ring is used instead of an expansion device. The lipped ring has a
circular section 315 with a diameter smaller than the narrowest
portion of a manhole opening. The measuring device pole is
connected to support beams 320 that are connected to the interior
portions of the circular section. Also connected to the top of the
circular section is a thin lip 325 that has a diameter
substantially similar to a manhole cover. Because the thin lip
diameter, it is nearly impossible for the lipped ring to
accidentally fall into the sewer.
[0151] FIG. 53 shows a main tube 45 having a plurality of thermal
flow heat sensors 321 imbedded in the mobile end and radially
disposed about the data acquisition device for measuring the flow
rate of a solution. Proximal to the heat sensors are heat sources
322 for quickly warming up the heat sensors to a desired
temperature. FIG. 54 shows a simplified schematic of a heat sensor
measuring the flow rate of a solution 30. Initially, a control
device 323 monitors the ambient temperature of the heat sensor.
Next, the control device operates the heat source until the heat
sensor has reached a predetermined temperature. The heat source is
then disengaged and readings from the heat sensor are recorded at
various intervals. Based on the measured ambient temperature and
the rate at which the heat sensor returns to ambient levels, the
flow rate of the solution can be determined. Faster solution flow
rates cause a faster return to ambient temperature levels. In one
embodiment of the invention, numerous heat sensor and heat source
pairs are imbedded in the main tube in order to allow for flow rate
detection at multiple locations on the device. Additionally, the
response from multiple sensors allows for improved flow measurement
by using statistical averaging.
[0152] FIG. 53 also illustrates a cylindrical waterproof
compartment circumscribed about and encapsulating the data
acquisition device, where the cylindrical waterproof compartment
has a width substantially similar to the inner diameter of the
flexible shaft/tube. The waterproof compartment has a threaded
section slightly exterior to the flexible tube. The threaded
section may cooperate with a threaded end cap like the ones
illustrated in FIGS. 5, 6, 20, 21, and 22.
[0153] FIGS. 55 and 56 show sample temperature response curves for
fast moving and slow moving solutions, respectively. In both the
fast moving solution measurement 326 and the slow moving solution
measurement 331, the ambient temperature measured during the
ambient temperature/initial stage 327 before the heat source is
engaged. Some time after the heat source is engaged, the heat
sensor reaches a set point 328 that causes the heat source to be
disengaged. Depending on the configuration used, the time duration
needed to reach the set point could be on the order of
milliseconds. Following the disengagement of the heat source, a
relative rapid cool down period 329 occurs when the sensor is
submersed in a quickly moving solution. The rate of temperature
change is indicative of a velocity of the fluid flow. When the
solution is flowing slowly, a temperature increase in the solution
near the heat sensor 321 decreases the rate of heat transfer to the
solution and causes a relatively slow cool down 332 of the heat
sensor.
[0154] FIG. 54 is a single function data chart 330 showing recorded
data 335 collected by a single monitoring device as a function of
time. In FIG. 54, a rain event occurred between 1:30 AM and 5:30 AM
that caused an increase in the flow rate through the sewer between
2:30 AM and 11:30 AM. In the preferred embodiment of the invention,
the data is collected at 5 minute intervals in order to reduce data
acquisition device power consumption.
[0155] The low cost and ease of use of the present invention
facilitates the usage of multiple monitoring devices over a wide
area in order to gain a better understanding of the flow rate
through the sewer systems. FIG. 58 shows a street map 340 with
markers 345 showing the hypothetical placement of multiple
monitoring devices placed on a street map. Positioning monitoring
devices in close proximity to each other reduces the length of
sewer pipe that must be search when a blockage or inflow between
the devices is identified.
[0156] Recent developments in satellite, mapping and computer
technology have led to the increased availability of precise
geographic maps and data on the internet. Highly accurate and
detailed street and topographic maps, as well as aerial satellite
photographs, are now readily available on the internet for nearly
every location in the United States and many populated areas
throughout the world. This information and data, however, has not
yet been effectively utilized in the study and analysis of waste
and storm water conveyance systems.
[0157] Sanitary sewer system authorities also maintain maps of
their sanitary and storm water sewer systems. These maps, which
detail all piping and access points, are the first step in
analyzing any sewer system. If a digitized computer file of the
system map is not available, one may be created from a paper copy
of the map.
[0158] Once a sewer system map has been obtained from the system
authority and the topographical map, street map and aerial
photograph of the same area have been obtained, the maps may be
combined using commercially available mapping software. By
identifying a particular point on each map or photograph with the
same precise latitude and longitude, the maps and aerial photograph
may be precisely aligned with one another.
[0159] FIG. 59 is the street map shown in FIG. 58 with the addition
of a sanitary sewer system overlay 350. In addition to overlaying a
sewer system onto a street map, representations of sewer systems
may also be overlaid onto aerial or satellite photography. These
maps may be downloaded from the internet by identifying the
geographic location by name or by identifying the latitude and
longitude for which a map is desired.
[0160] FIG. 60 shows the data read out from some of the data
monitoring devices of FIG. 59. In addition to outputting the data
collected onto a chart. Computer software may be used to represent
some of the data in FIG. 56 in an overlay on the map of FIG. 59.
Methods of representing the flow rates at various times may include
using colors, numbers as shown in FIG. 61, or symbols as shown in
FIG. 62. Differences in flow rates between monitoring devices may
also be represented as colors, numbers, symbols, or cross hatching
as shown in FIG. 63. Measured flow data may be overlaid on a
variety of places such as the location of the monitoring devices,
as seen in FIGS. 61 and 62, between the monitoring devices as shown
in FIG. 63, or on the monitoring device markers as shown in FIG.
64. Flow rate derivatives may be represented on charts showing the
change in flow rates. Information related to the integrated flow
rate may be shown to illustrate the total volume of liquid passing
through the sewer system in a given time.
[0161] Mapping software may be used to convert the topographical
map to a three dimensional image of the geographic area under
study. The mapping software may also be used to overlay the sewer
system piping, the street map and/or the aerial photograph (or some
combination thereof) on the three dimensional image, as represented
in FIG. 65. The resulting data, shown in FIG. 66, may then be
studied.
[0162] The geographic features of the area under study may be
evaluated from the three dimensional image. The aerial photograph
of the area may be overlaid on the three dimensional image to show
the ground cover and other geographic features (including existing
waterways) that might influence storm water runoff during wet
weather. In particular, troughs, valleys and depressions in the
three dimensional image may be identified as potential sources for
the collection of storm water. Once these locations are identified
and the course of significant storm water runoff is predicted, the
sanitary sewer system map may be overlaid on the three dimensional
image and the sections of piping located at these storm water
collection points identified. By overlaying the street map, the
precise location of these potential infiltration and inflow points
may be further specified.
[0163] By identifying potential infiltration and inflow points
using this method, any inspection or flow measurement study may be
concentrated on those areas immediately adjacent (upstream and
downstream) to where infiltration and inflow is most likely. Thus,
rather than studying the entire system, or dispersing flow
measurement devices and personnel throughout the system, the study
may be concentrated in a particular area or areas. This advance
analysis leads to cost and time savings in both equipment and
personnel, and allows the sewer system authority to proceed to the
next step of closer inspection and analysis with greater
confidence.
[0164] Multiple sewer systems, such as sanitary sewers 350 and
storm sewers 355, may be overlaid onto topographic and street maps
as shown in FIG. 63. Methods of differentiating between overlaid
sewer systems include the use of hatching, multiple colors, and
textures. In addition to overlaying sewer systems onto a street
map, three dimensional representations of multiple sewer systems,
as shown in FIG. 64, may be used in the study of the sewer
systems.
[0165] FIG. 69 shows an alternative embodiment of the invention
where the sewer system is represented by bold lines, the flow
direction indicators 360 illustrate the directions of flow, and
x-symbols 365 show the location of a sewer blockage.
[0166] FIG. 70 shows a data analysis tool 370 displaying a street
map 375 with four flow monitors. A portion of the data collected by
the flow monitors is illustrated as ribbons 380. Each ribbon
corresponds to a flow monitor, time is represented on the y-axis or
floor of the graph, and the numerical values of the data collected
(fluid level, pressure, flow rate, etc.) are represented on the
z-axis or walls of the chart. Shown below the ribbons is a line
graph 385 representing all the data collected by the monitors, or
the data collected by another monitor (such as the flow rate into a
water treatment facility). The time period represented by the
ribbon chart is highlighted on the line graph as the area without
cross-hatching. The increase in flow at a certain time is
indicative of a rain event. In the data analysis tool shown in FIG.
70, the data recorded by the four flow monitors is substantially
similar indicating the sewer is operating properly.
[0167] The time duration displayed by the ribbon chart may be
increased to better illustrate long term trends or shortened to
highlight key monitoring times such as immediately before, during,
and after a rain event. Although only one variable is shown on the
z-axis, multiple sets of data may be over laid for a single
monitor. For example, pressure and tilt may be displayed on a
single chart with pressure data offset from the tilt data for
clarity.
[0168] FIG. 71 shows a data analysis tool substantially similar to
the tool shown in FIG. 70. Flow monitors A, B, and D indicate
substantially similar relative fluid levels, while monitor C 390
indicates an increase in fluid level before the other monitors.
Additionally, the fluid level recorded at monitor C remains
elevated after the other monitors return to pre-rain event fluid
levels. The early increases of the fluid levels at monitor C and
the lengthened return to pre-rain event levels are indicative of a
problem in the sewer system.
[0169] FIG. 72 is substantially similar to FIG. 71 except that a
problem in the sewer system is indicated by monitor D 395 instead
of monitor C.
[0170] FIG. 73 shows the same data as in FIG. 62 except that the
data is represented by 3D area charts instead of ribbons.
Additionally the axes are labeled with time, flow monitor, and
fluid level.
[0171] FIGS. 74 and 75 show the data collected from over 35 fluid
monitors during a rain event. The fluid level and flow rate data
for each monitor are illustrated on the z-axes of the charts. FIG.
74 displays time on the y-axis, while FIG. 75 displays time on the
x-axis. With over 35 fluid monitors, the clarity of the data is
significantly enhanced by displaying time on the y-axis. In
addition to the data collected from the sewer flow monitors, the
sewer treatment plant flow rate 400 is also displayed on the left
side of the chart in FIG. 74. As with the other examples of the
data analysis tool, only a portion of the data collected is
displayed to better highlight key monitoring times. A strip chart
showing data from the entire monitoring period is displayed below
the ribbon chart. In this example of the invention, the
representative data is collected at the sewer treatment plant.
[0172] In FIG. 74, a cluster of fluid monitors show an early
increased flow rate (M-009 D721 fox river 405 through M-0349 D 333
La Honda 410). A clustering of early rising fluid levels is
indicative of a problem in the sewer system. The problem is not
necessarily near the clustering of early rising monitors and
blockage significantly downstream may be responsible.
[0173] FIGS. 76 and 77 present data similar to the data presented
in FIG. 70, except that the collected data is presented as 3D
overlays 415 (similar to those shown in FIG. 69) onto a 3D street
map. The presentation of the data as an overlay may be beneficial
in identifying problem locations in complex and highly
interconnected drainage systems. FIG. 76 shows substantially
similar data from four monitors which suggests that the displayed
portion of the sewer system 420 is functioning properly. FIG. 77
shows three monitors with substantially similar data and one
monitor with a significant early increase in fluid level. Such a
result is indicative of a flow restriction between the two monitors
on the right portion of the figure. Alternatively inflow and
infiltration between the middle two monitors could result in an
early increase in fluid level.
[0174] FIG. 78 illustrates a flow chart for monitoring and
maintaining the integrity and operability of a sewer system. In a
pre-deployment phase 425, information is gathered on the sewer
system (such as maps), the watershed (rivers, topography, etc.),
and hot spots (where previous work has been done, previous
overflows, etc). The collected data is then analyzed to determine
locations for the initial placement of the monitors. Pre-deployment
analysis increases the likelihood of the initial placement of flow
monitors yielding actionable data.
[0175] After the initial placement of the monitors, data is
collected. In one embodiment of the invention, monitors are placed
in 5%-10% of the manholes in a sewer collection system. The
monitoring period may be a specified time (30 days, 2 months,
etc.), or it may be until a predetermined rain event has occurred
such as 0.5 inches of rainfall in less than 6 hours.
[0176] After the monitoring period, data is collected from the
monitoring devices and synthesized into a database and analyzed in
the manners previously disclosed. If there is a strong indication
of a problem in a specific location, closed circuit television
(CCTV) analysis of the pipe may be performed in order to further
test the pipe. If pipe deterioration is observed, the pipe may be
repaired. If there is a strong indication of a problem and pipe
deterioration is not observed, it is indicative of inflow and
infiltration (I&I). After repairing the pipe (or if I&I is
suspected), the location is further monitored.
[0177] When there is an indication of a problem in the sewer
system, but not a strong enough indication to warrant CCTV analysis
of the pipes, the flow monitors may be clustered around key points
of interest to support or refute the suggestion of a problem.
[0178] In one embodiment of the method disclosed in FIG. 77, a
large number of flow monitors are used to collect a large amount of
data in a brief period of time. For example, a large number of
monitors may be used when the cause of a known problem needs to be
found. With a sufficient number of flow monitors, repositioning of
the monitors for a second monitoring period may not be necessary.
Alternatively, in another embodiment of the method of FIG. 78, a
relatively small number of flow monitors may be used on a continual
basis to analyze the operability of a sewer system.
[0179] While the principles of the invention have been shown and
described in connection with specific embodiments, it is to be
understood that such embodiments are by way of example and are not
limiting. Consequently, variations and modifications commensurate
with the above teachings, and with the skill and knowledge of the
relevant art, are within the scope of the present invention. The
embodiments described herein are intended to illustrate best modes
known of practicing the invention and to enable others skilled in
the art to utilize the invention in such, or other embodiments and
with various modifications required by the particular
application(s) or use(s) of the present invention. It is intended
that the appended claims be construed to include alternative
embodiments to the extent permitted by the prior art.
* * * * *