U.S. patent application number 11/837066 was filed with the patent office on 2008-02-14 for energy recovery system in an engine.
Invention is credited to Triantafyllos P. Tafas.
Application Number | 20080034728 11/837066 |
Document ID | / |
Family ID | 38002376 |
Filed Date | 2008-02-14 |
United States Patent
Application |
20080034728 |
Kind Code |
A1 |
Tafas; Triantafyllos P. |
February 14, 2008 |
ENERGY RECOVERY SYSTEM IN AN ENGINE
Abstract
A energy recovery system for an internal combustion engine which
dynamically allocates heat energy to multiple vehicle accessory
systems
Inventors: |
Tafas; Triantafyllos P.;
(Rocky Hill, CT) |
Correspondence
Address: |
KELLEY DRYE & WARREN LLP
400 ALTLANTIC STREET , 13TH FLOOR
STAMFORD
CT
06901
US
|
Family ID: |
38002376 |
Appl. No.: |
11/837066 |
Filed: |
August 10, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11266948 |
Nov 4, 2005 |
|
|
|
11837066 |
Aug 10, 2007 |
|
|
|
Current U.S.
Class: |
60/39.182 |
Current CPC
Class: |
B60L 50/16 20190201;
F01N 5/04 20130101; B60L 2240/36 20130101; B60L 3/0023 20130101;
Y02T 10/7072 20130101; F01N 5/02 20130101; Y02T 10/70 20130101;
F01K 23/10 20130101; F02G 2260/00 20130101; F01K 23/065
20130101 |
Class at
Publication: |
060/039.182 |
International
Class: |
F02G 5/02 20060101
F02G005/02 |
Claims
1-21. (canceled)
22: An internal combustion engine system comprising: an internal
combustion engine producing heated emissions from one or more
combustion chamber(s); a gaseous matter generator connected
proximal to said combustion chamber(s), said gaseous matter
generator operatively configured to receive said heated emissions
from said one or more combustion chamber(s) and to apply the heat
from said heated emissions to produce gaseous matter.
23: An internal combustion engine system, in accordance with claim
22, wherein said gaseous matter is steam.
24: An internal combustion engine system, in accordance with claim
22, further comprising: a windshield wiper blade heater having a
closed-loop flow through conduit; and a closed-loop conduit
operatively connecting said gaseous matter generator with said
windshield wiper blade heater.
25: An energy recovery system in a vehicle comprising: a heat
source, containing a fluid, comprising an input source fluid port
and an output source fluid port; a distribution allocator,
containing said fluid, connected to said heat source by a fluid
conduit, comprising electrically operable fluid valves operatively
configured to interconnect a plurality of input fluid ports and
output fluid ports; a fluid pump, containing said fluid,
operatively connected to said distribution allocator, said fluid
pump capable of pumping fluid through said heat source and into
said distribution allocator; and a windshield wiper blade heater,
containing said fluid, and having a closed-loop flow-through
conduit connected to at least one input port and one output port of
said allocator.
26: An energy recovery system, in accordance with claim 25, wherein
said heat source further comprises a temperature sensor.
27: An energy recovery system, in accordance with claim 25, wherein
said windshield wiper blade heater further comprises a temperature
sensor.
28: An energy recovery system, in accordance with claim 25, wherein
said heat source is a heat-exchanger.
29: An energy recovery system, in accordance with claim 25, wherein
said heat source is a battery powered electrical heater.
30: An energy recovery system, in accordance with claim 25, wherein
said heat source is an electrical heater powered by electricity
generated from engine heat.
31: An energy recovery system, in accordance with claim 25, wherein
said heat source is powered by electricity produced by a
turbine-generator.
32: An energy recovery system, in accordance with claim 31, wherein
said turbine-generator is a steam powered turbine-generator.
33: An energy recovery system, in accordance with claim 25, wherein
said fluid is anti-freeze fluid.
34: An energy recovery system, in accordance with claim 33, wherein
said anti-freeze fluid is alcohol.
35: An energy recovery system, in accordance with claim 33, wherein
said anti-freeze fluid is methanol.
36: An energy recovery system, in accordance with claim 33, wherein
said anti-freeze fluid is ethylene glycol.
37: An energy recovery system, in accordance with claim 33, wherein
said anti-freeze fluid is propylene glycol.
38: An energy recovery system, in accordance with claim 33, wherein
said anti-freeze fluid is a mixture of ethylene glycol and
propylene glycol.
39: (canceled)
40: An energy recovery system, in accordance with claim 25, wherein
said heat source is chosen, on a priority basis, from the
prioritized group consisting of an electrical heater powered by
electricity generated from engine heat and a battery powered
electrical heater.
41: A multi-port fluid valve comprising: a circular cylindrical
outer shell having a top surface and a bottom surface, an inner
side surface and an outer side surface, and a plurality of
equi-angularly spaced fluid ports penetrating from said inner
surface to said outer surface; an circular cylindrical inner body
having a top surface, a bottom surface, an inner side surface an
outer side surface in rotating contact with inner side surface of
said circular cylindrical outer shell and internally comprising
isolated passageways whose entrance and exit apertures are
positioned on said outer side surface of said circular cylindrical
inner body; a means of rotating said circular cylindrical inner
valve body with respect to said circular cylindrical outer shell
comprising an electrical actuator.
42: (canceled)
43: A multi-port fluid valve, in accordance with claim 41, wherein
said electrical actuator is a motor.
44: A multi-port fluid valve, in accordance with claim 43, wherein
said motor is a stepper motor.
45: (canceled)
46: (canceled)
47: (canceled)
48: (canceled)
49: (canceled)
50: (canceled)
51: A multi-port fluid valve comprising: a circular cylindrical
outer shell having a top surface and a bottom surface, an inner
side surface and an outer side surface, and a plurality of
equi-angularly spaced fluid ports penetrating from said inner
surface to said outer surface; an circular cylindrical inner body
having a top surface, a bottom surface, an inner side surface an
outer side surface in rotating contact with inner side surface of
said circular cylindrical outer shell and internally comprising
isolated passageways whose entrance and exit apertures are
positioned on said outer side surface of said circular cylindrical
inner body; a means of rotating said circular cylindrical inner
valve body with respect to said circular cylindrical outer shell
comprising a hydraulic actuator.
52: A multi-port fluid valve comprising: a circular cylindrical
outer shell having a top surface and a bottom surface, an inner
side surface and an outer side surface, and a plurality of
equi-angularly spaced fluid ports penetrating from said inner
surface to said outer surface; an circular cylindrical inner body
having a top surface, a bottom surface, an inner side surface an
outer side surface in rotating contact with inner side surface of
said circular cylindrical outer shell and internally comprising
isolated passageways whose entrance and exit apertures are
positioned on said outer side surface of said circular cylindrical
inner body; a manual means of rotating said circular cylindrical
inner valve body with respect to said circular cylindrical outer
shell.
53: A multi-port fluid valve comprising: a circular cylindrical
outer shell having a top surface and a bottom surface, an inner
side surface and an outer side surface, and a plurality of
equi-angularly spaced fluid ports penetrating from said inner
surface to said outer surface; an circular cylindrical inner body
having a top surface, a bottom surface, an inner side surface an
outer side surface in rotating contact with inner side surface of
said circular cylindrical outer shell and internally comprising
isolated passageways whose entrance and exit apertures are
positioned on said outer side surface of said circular cylindrical
inner body; a means of rotating said circular cylindrical inner
valve body with respect to said circular cylindrical outer shell
comprising a pneumatic actuator.
54: A multi-port fluid valve as in claims 41, 51, 52, or 53,
further comprising a valve position sensor.
Description
[0001] This application is a continuation-in-part application of
U.S. patent application Ser. No. 11/266,948, filed Nov. 4, 2005.
All references cited in this specification, and their references,
are incorporated by reference herein where appropriate for
teachings of additional or alternative details, features, and/or
technical background.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] The present invention includes an energy capture system and
method for recovering heat energy from the exhaust gases of an
internal combustion engine.
[0004] 2. Description of Related Art
[0005] In conventional internal combustion engines, a mixture of
air and fuel is introduced into the engine, where it is compressed
and then ignited. The burning gases expand, do work, and then are
expelled from the engine. The actual amount of kinetic energy or
mechanical work that is extracted from the internal combustion
generally depends upon the thermal efficiency of the internal
combustion engine. What is not extracted is expended as waste
heat.
[0006] Thermal efficiency is the percentage of energy taken from
the combustion which is actually converted to mechanical work. In a
typical low compression engine, the thermal efficiency may be only
about 26%. In a highly modified engine, such as a race engine, the
thermal efficiency may be about 34%.
[0007] In a generic internal combustion engine, only 20% of the
total energy available may be converted to useful energy. Of the
remaining 80% of the total energy, approximately 38% may be lost
through exhaust heat, 36% through water heating in the cooling
system and 6% through motor friction.
[0008] There have been various schemes to capture energy from the
exhaust gases and heated engine cooling water.
[0009] U.S. Pat. No. 4,439,999, Mori, et aL., discloses an internal
combustion engine and an absorption type refrigeration system which
makes use of both the engine exhaust gas and the heated engine
cooling water. The internal combustion engine and the absorption
type refrigeration system are combined in such a manner that the
exhaust gas of the internal combustion engine is utilized as the
heat source for a first gaseous refrigerant generator having the
highest operating temperature in the system, while heated engine
cooling water is utilized as the heat source for another generator
which operates at a temperature lower than the operating
temperature of the first gaseous refrigerant generator.
[0010] U.S. Pat. No. 6,119,457 to Kawamura describes a heat
exchange apparatus having high and low temperature heat sources
comprising porous material provided in an exhaust passage from a
ceramic engine in communication with a supercharger connected to
the ceramic engine. The heat exchange apparatus comprises a high
temperature heat exchanger having a steam passage provided in an
exhaust gas passage through which an exhaust gas passes whereby
steam is heated, and a low temperature heat exchanger provided in
the portion of the exhaust gas passage on the downstream side of
the high temperature heat exchanger which has a water passage for
heating water by the exhaust gas. The ceramic engine has a steam
turbine type supercharger provided with a steam turbine driven by
the steam from the high temperature heat exchanges, a compressor,
and a condenser which separates a fluid discharged from the steam
turbine into water and low temperature steam. Pressurized air from
the compressor is supplied to the combustion chamber, which presses
down a piston to carry out compression work during an intake
stroke. Thus, the supercharger is driven by the thermal energy
recovered from an exhaust gas by the same heat exchanger
apparatus.
[0011] An example of an energy recovery system is also disclosed in
Japanese Patent Laid-Open No. 1799721993. This energy recovery
system has an energy recovery unit provided with a first turbine
installed in an exhaust passage and a generator operated by the
first turbine, a turbocharger provided with a second turbine
connected to an outlet-side passage of the first turbine and a
supercharging compressor operated by the second turbine, and a
waste gate provided in the outlet-side passage of the first
turbine. The energy recovering operation is carried out by the
energy recovery unit when the temperature of the exhaust gas is
high.
[0012] Exhaust gas energy from an internal combustion engine may
also be used to provide a heated water source, for example, while
the mechanical power of the engine may be used simultaneously to
generate electricity. In Japanese Patent Laid-Open No. 33707/1994,
there is disclosed a system making use of exhaust gas energy from a
turbocharger attached to a heat insulation type gas engine to
produce steam that is used to drive a steam turbine so as to
produce electric energy and heated water. A turbocharger is driven
by the exhaust gas energy from the heat insulating gas engine, and
the generator/energy recovery unit is driven by the exhaust gas
energy from the turbocharger. The thermal energy of the exhaust gas
directed to the energy recovery unit is converted into steam by a
first heat exchanger, and recovered as electric energy by driving a
steam turbine. Heated water is generated by the high-temperature
steam from the steam turbine by an operation of a second heat
exchanger, and utilized as a hot water supply source.
[0013] In U.S. Pat. No. 4,803,958 to Erickson, there is disclosed
an open-cycle absorption apparatus for compressing steam from a low
pressure to a higher pressure. The apparatus is used for upgrading
low-temperature jacket-cooling heat from an internal combustion
engine to useful pressure steam. A simple heat-exchange apparatus
is involved, using the extra temperature availability of the hot
exhaust gas as the driving medium.
[0014] There have recently been higher efficiency vehicles powered
using hybrid concepts that involve internal combustion engines in
combination with an electric generator that powers an electric
motor. The generator utilizes some of the kinetic energy that would
otherwise be converted into heat by friction in the vehicle is
braking system. While systems such as described above in
combination with such hybrid systems may further improve energy
storage in such cars, the loss of energy through the emission
system would remain high. What is needed is a system that would
convert a significant percentage of the power lost as heat to
electrical power and create a more efficient hybrid vehicle.
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a drawing showing the integration of components of
an embodiment energy recovery system, including a heat collection
subsystem and a heat expending exhaust subsystem, as well as a
two-stage turbine that interfaces with the two subsystems
simultaneously;
[0016] FIG. 2 is a drawing showing the incorporation of the energy
recovery system of FIG. 1 in an automobile, according to an
embodiment of the present invention.
[0017] FIG. 3 is a drawing schematically showing an energy recovery
system which derives heat from various engine components and
allocates the energy to a plurality of accessories. For purposes of
clarity, the figure shows only the forward paths from the heat
sources to the accessories. A complete presentation would also
include the corresponding return paths returning from the
accessories to the heat sources.
[0018] FIG. 4 is a drawing showing a schematic embodiment of a
4-port valve for use in the energy recovery system.
[0019] FIG. 5 is an embodiment of a windshield which is de-iced by
fluid heated by an internal combustion engine.
[0020] FIG. 6 is a drawing showing a windshield wiper that is
heated by fluid warmed by the recovered heat of an internal
combustion engine.
SUMMARY OF THE INVENTION
[0021] The disclosed system comprises an energy recovery system in
internal combustion engines.
[0022] In a first embodiment, the energy recovery system comprises
a steam generating chamber located proximal to the engine, such as
immediate contact with the exhaust manifold, that is operatively
configured to receive exhaust fumes from one or more combustion
chambers in the internal combustion engine and one or more fluids
from a fluid reserve and to convert such fluid into steam. In such
embodiment, the steam generated in the steam chamber is directed
through a steam inlet to an electrical generator component
comprising a turbine and electrical generator. The electrical
generator component is operatively configured with respect to the
steam inlet such that the steam turns the turbine which in turn
causes the generator to generate electricity. The electricity
produced may be used by the engine contemporaneously or stored for
later use, for example, when the engine is not using combustion to
generate rotation of the wheels on a hybrid vehicle.
[0023] In one embodiment, the system involves a heat collection
system proximal to an internal combustion engine block, the heat
collection system configured to transfer heat to a steam generating
boiler. Both the steam and exhaust gases simultaneously drive a
turbine of an electric generator which in turn is connected to an
electric motor. The power from the electric motor supplants the
power from the internal combustion engine to propel a vehicle, for
example. In one embodiment, the heat collection system is
immediately proximal to the engine, such as connected to the
manifold.
[0024] Aspects disclosed herein include:
[0025] An internal combustion engine system comprising an internal
combustion engine producing heated emissions from one or more
combustion chamber(s); a steam generator connected proximal to the
combustion chamber(s), the steam generator operatively configured
to receive the heated emissions from the one or more combustion
chamber(s) and to apply the heat from the heated emissions to
produce steam, and configured to direct the steam towards a turbine
in a manner to cause the turbine to turn; an electric generator
operatively connected to the turbine, the electric generator
operatively configured to produce electricity upon turning of the
turbine.
[0026] An energy recovery system comprising an engine having a
combustion chamber; a coolant subsystem communicating with the
combustion chamber; an exhaust subsystem integral to the combustion
chamber; a boiler in communication with the coolant subsystem, the
boiler operatively configured to generate steam in cooperation with
the coolant subsystem; an energy converter operatively configured
to simultaneously receive the steam from the boiler and to receive
the exhaust gases from the exhaust subsystem and to convert energy
associated with the steam and exhaust gases into mechanical energy,
an electric generator in communication with the energy converter
operatively configured to convert the mechanical energy from the
energy converter to electrical energy, wherein the engine and the
electric generator are cooperatively configured to propel a
vehicle.
[0027] An energy recovery system comprising an engine having a
combustion chamber producing hot pressured exhaust gases; an energy
collection subsystem housing a liquid energy carrier medium, the
energy collection subsystem operatively configured to allow heat
from the hot pressured exhaust gases of the combustion chamber to
pass into the liquid energy carrier medium; an energy chamber
connected to the energy collection subsystem operatively configured
to convert the energy carrier medium from a liquid to a gaseous
state; a combustion exhaust subsystem integral to the combustion
chamber, the combustion exhaust subsystem operatively configured to
receive hot pressured exhaust gases from the combustion chamber; an
energy converter operatively configured to communicate
simultaneously with the energy chamber and with the combustion
exhaust subsystem, the energy converter having a shaft operatively
configured to be rotated by the energy carrier medium in a gaseous
state and to convert pressure energy from the exhaust gases in the
combustion exhaust system into mechanical power; a converter
attached to the energy converter operatively configured to convert
the mechanical power of the energy converter to electrical power;
wherein the engine and the converter are configured to provide
energy to propel a vehicle.
[0028] A method of recovering waste heat energy from exhaust gases
produced by combustion in an internal combustion engine, the method
comprising the steps of transferring heat from the engine to a
primary coolant loop; directing exhaust gases from the engine to a
first impeller in a first chamber connected to a shaft operatively
connected to an electric generator; directing the exhaust gases
from the first chamber to an exhaust conduit; transferring heat
from the exhaust conduit to a heat conducting member connected to a
secondary cooling loop; transferring heat from the primary and
secondary cooling loops to a second chamber operatively configured
to produce steam; directing steam from the second chamber to a
second impeller operatively connected to the shaft operatively
connected to the first impeller, the second chamber being
positioned in a third chamber; directing the steam from the third
chamber to a condenser operatively configured to condense the steam
to liquid; directing the liquid from the condenser to the primary
cooling circuit.
[0029] In a further embodiment, heat from the engine and exhaust
system may be used to heat a working fluid that may then be used to
operate, or heat, a variety of passenger compartment and engine
accessories. Examples of such accessories include windshield
de-icers, windshield wiper heaters, locks, door handles, windshield
wiper fluid tank heaters, electric motor bearing heaters, battery
heaters, passenger compartment contact heaters, fuel tank heaters,
and brake system component heaters.
[0030] The capacity of the energy recovery system may not be
sufficient to simultaneously operate the full suite of accessories.
In addition, the duty cycle of some of the accessories may depend
on environmental conditions. The distribution of the available
heated working fluid may therefore be selectively controllable on a
prioritized basis. Such distribution may be manually selected or
automatically selected by means of a feedback system employing
sensors on one or more of the accessories.
[0031] In another embodiment, various engine components have
different temperature and heat capacity characteristics. As an
example, a catalytic converter produces extremely high temperatures
while the engine water jacket has a high heat capacity. The dynamic
behavior of temperature of these engine components additionally
exhibits different time responses, especially on engine starting.
An aspect of this embodiment is the matching of the temperature and
heat capacity characteristics of the individual heat sources,
coupled to the various engine components, to the accessory heat
demands.
[0032] In an embodiment herein disclosed, the working fluid is
heated by means of a plurality of heat-sources in contact with
suitable engine and exhaust system components. The heated working
fluid is pumped, by means of insulated conduits, to a distribution
allocator which, in turn, routes appropriate flows of working fluid
to selected accessories and accessory heaters. The energy-expended
working fluid is returned, via the distribution allocator, to the
heat-sources.
[0033] The distribution allocator comprises, in one embodiment, a
matrix of electrically actuated valves that can perform the
necessary routing. A controller that actuates the valves may be
based on manual inputs, dynamically established priorities and
sensor detected environmental conditions, or a combination of the
same, to control each valve in the matrix. The controller may
include a computer which executes stored programs to set the
correct valve settings. A network of sensors may be distributed at
appropriate monitoring sites and provide real time measurements to
the controller. When heated fluid is used to effectuate heating of
the working fluid, one or more working fluid pumps may be located
at various points in the insulated conduit network to power
circulation. Of course, accessories described herein may be heated
by means of electrical input rather than heated fluid; that is,
accessories may include electrical heaters, rather than, or in
addition to, fluid conduits.
[0034] In a further embodiment, it is recognized that different
engine and exhaust system components can provide differing
temperatures and quantities of heat and have different time-heat
profiles relative to engine starting and operating cycles. The
associated heat-sources call therefore supply working fluids having
differing dynamically varying characteristics. The distribution
allocator, to the extent possible, matches supply characteristics,
of the various sources, to the individual accessory demands.
[0035] Embodiments herein disclosed include an energy recovery
system in a vehicle comprising: a heat source, containing a fluid,
comprising an input source fluid port and an output source fluid
port; a distribution allocator, containing the fluid, connected to
the heat source by a fluid conduit, comprising electrically
operable fluid valves operatively configured to interconnect a
plurality of input fluid ports and output fluid ports; a fluid pump
operatively, containing the fluid, connected to the distribution
allocator, the fluid pump capable of pumping fluid through the heat
source and into the distribution allocator; and a windshield wiper
blade heater, containing the fluid, and having a closed-loop
flow-through conduit connected to at least one input port and one
output port of the allocator.
[0036] Further embodiments herein disclosed include a multi-port
fluid valve comprising: a circular cylindrical outer shell having a
top surface and a bottom surface, an inner side surface and an
outer side surface, and a plurality of equi-angularly spaced fluid
ports penetrating from the inner surface to the outer surface; an
circular cylindrical inner body having a top surface, a bottom
surface, an inner side surface an outer side surface in rotating
contact with inner side surface of the circular cylindrical outer
shell and internally comprising isolated passageways whose entrance
and exit apertures are positioned on the outer side surface of the
circular cylindrical inner body; a means of rotating the circular
cylindrical inner valve body with respect to the circular
cylindrical outer shell.
DETAILED DESCRIPTION OF THE INVENTION
[0037] In an embodiment shown in FIG. 1, there is illustrated an
energy recovery system 10 for an internal combustion engine 20.
Internal combustion engine 20 is powered by the expansion of hot
combustion products of fuel directly combusted within the engine.
As is known, a piston internal combustion engine works by burning
hydrocarbon or hydrogen fuel that presses on a piston, which does
work, such as propelling an automobile; and a jet engine works as
the hot combustion products press on the interior parts of the
nozzle and combustion chamber, directly accelerating the engine
forwards. The engine of such embodiment may be a gasoline or diesel
engine, for example, a two-cycle, four-cycle or a rotary Wankle
engine. Energy recovery system 10 shown in FIG. 1 is configured to
capture and convert specific energy, that is, the amount of energy
per unit mass of the fuel burned in engine 20 into useful work that
is otherwise wasted, for example, in the form of heat that escapes
into the environment.
[0038] In certain internal combustion engines, only a portion
(about 20%) of the total available specific energy in the consumed
fuel is directly converted to mechanical work by the action of the
hot combustion products on engine components such as pistons (which
maybe connected to a shaft, which in turn may do work such as
rotating the wheels on a car--shown in FIG. 2). Of the remaining
portions of energy lost through exhaust gases 30 and through water
heating in the radiator 40 are converted to useful work through the
use of a two-stage turbine 50 as shown in FIG. 1.
[0039] In an aspect of an embodiment, the two-stage turbine 50 is
configured to operate with impellers 57 that are mounted onto a
common shaft 59 which spans two chambers 53 and 55, and which
drives an electric generator 90 as shown in FIG. 1. The impellers
are rotatable by gaseous matter such as the exhaust gases issuing
from exhaust subsystem 30 and steam issuing from exhaust heat
conductor 80, as explained further below. Alternatively, only one
impeller may be employed with rotation by gaseous inflow or steam
alone, or both gaseous inflow and steam. The electricity generated
by generator 90 provides additional energy recovered from the
otherwise would-be wasted heat energy to be put into useful work.
It will be appreciated by those skilled in the art that this
additional energy recovered from waste heat alone can supplant the
energy recovered from kinetic energy dissipated in the braking
system of an automobile, and hence, can be used to enhance the
current hybrid technologies for automobiles. The efficiency of
current internal combustion engines may be significantly improved
thereby, for example, by a factor of two or more.
[0040] Another embodiment of the present invention involves pick-up
of heat and exhaust gas from engine block 22 and engine head 24
(shown separate from the engine block for purposes of illustration)
at points closest to the heat source generated by the combusting
fuel in combustion chambers of engine block 22 in FIG. 1. The main
cooling circuit comprises a primary loop 60 (shown in solid line
arrows) which circulates a coolant (such as water). Exhaust heat
conductor 80 generates steam which enters chamber 53 of the
two-stage turbine 50 to turn shaft 59 connected to electric
generator 90. In one aspect, the electricity from generator 90 may
be used to increase steam production from exhaust heat conductor
80. The expended steam is then collected at condenser 85 where
another phase change occurs from steam to liquid, thus completing
the first cooling loop 60, as shown in FIG. 1.
[0041] In another aspect, a secondary loop 65 picks up condensed
steam from condenser 85 (shown in FIG. 1). Exhaust 30 from internal
combustion engine 20 is directed to chamber 55 where the
high-pressure hot gases perform work on the turbine shaft 59, and
leave the system through exhaust conduit 35. A shroud over exhaust
conduit 35 may be configured to augment (using highly thermal
conductive ceramic heat sinks, for example) heat conduction from
the exhaust gases to the secondary loop 65. In one aspect,
secondary loop 65 is connected ultimately to exhaust heat conductor
80. Valves may be used to adjust and balance the coolant flow
through loops 60 and 65.
Relatively cool and low speed exhaust gases may leave the system
through exhaust conduit 35 as shown in FIG. 1.
[0042] Various aspects of certain embodiments of the present
invention may be superimposed schematically over the various known
components of an automobile 100 as depicted in FIG. 2 and the
labeled known components are not described here so as to not
obscure the key aspects of the present invention. The cooling loops
are not shown as they can be arranged in any number of ways to
connect the components of embodiments, for example, engine block
22, exhaust heat conductor 80, condenser 85, radiator 40, two-stage
turbine 50, electric generator 90 and exhaust conduit 35.
Electricity generated by electric generator 90 can be used to power
the drive of the car, or power any component of the car, or the
electricity can be stored in the car battery or secondary storage
battery 37. It will be understood that the placement of the
disclosed new components can be varied dependent upon factors
affecting space, and safety considerations of an automobile. It
will also be obvious to those skilled in the art that the energy
recovery system disclosed herein can be applied to improve the
efficiency of any engine used to produce useful work.
[0043] In operation, an embodiment of a method of recovering waste
heat energy in an internal combustion engine 20 involves
transferring the heat developed in internal combustion engine 20 to
primary cooling loop 60 at the closest points to the combusting
fuel in the chambers (as, for example, receiving emissions directly
from the exhaust manifold) (see, FIG. 1). The heat carrying coolant
fluid, for example, water in loop 60 is directed to a suitably
designed exhaust heat conductor 80 where the fluid is heated to
generate advantageously pressured steam. Steam is next allowed to
enter two-stage turbine 50 to drive impeller 57 mounted on shaft
59, which in turn drives electric generator 90. The expended steam
is then condensed into liquid through a second phase change in
condenser 85. The coolant liquid then completes the circuit back to
engine block 22 joining primary cooling loop 60. The method may
involve circulating the coolant through the engine block 22 as well
as the engine head 24 to promote most efficient energy recovery
from the combusting fuel in combustion engine 20.
[0044] In an aspect of an embodiment, the method also involves
directing the exhaust gases 30 to the two-stage turbine 50 as shown
in FIG. 1. The high speed exhaust gases are directed to impart
energy to another impeller 57 of the turbine which further enhances
the rotation of shaft 59, which in turn drives the electric
generator 90. Before the expended gases are ejected out into the
environment via an exhaust conduit 35, any remaining heat energy
may be extracted by means of further heat conducting elements and
then transferred appropriately into the system as, for example,
into secondary loop 65. In another embodiment, exhaust gas may pass
first from the turbine exhaust stage and subsequently be channeled
to exhaust heat conductor 80.
EXAMPLE 1
[0045] The exhaust from the exhaust manifold of a single piston
outboard motor is directed to a water-jacketed chamber. The
temperature of the exhaust and the water in the jacket is measured
by way of thermocouples during the combustion of 100 ml of regular
gasoline. Steam is generated with maximum temperatures over
400.degree. C. measured in the gas exhaust.
[0046] Other embodiments of the energy recovery system embodiment
of the present invention utilize the heat generated in an internal
combustion engine directly or from components of the exhaust
system. In an embodiment, the heat energy may be efficiently
transported from the various heat sources and the heat loads by
means of a working fluid flowing through insulated conduits.
[0047] There are a variety of heat sources available from the
vehicles engine and associated support components other than heat
generated by, or subsequent to, firing of the internal combustion
engine. For example, a heat source may be an electrical heater
powered by the steam turbine driven generator described above or by
the battery of the vehicle itself. It is also possible to heat the
working fluid directly with the generated steam.
[0048] In a system analogous to a hybrid vehicle propulsion system,
the electrical heater may obtain its power from the steam turbine
driven generator when sufficient steam is available. When steam is
not available to drive the generator, the electrical power for the
heater may be derived from a rechargeable battery. This hybrid
approach permits the system to operate before the engine is
started. Other heat sources may be employed such as heat exchangers
thermally coupled to various engine and exhaust system components
which heat during normal engine operation.
[0049] Referring to FIG. 3, an energy recovery system embodiment
105 is schematically diagrammed and includes a plurality of heat
sources 110 affixed to engine and exhaust system components, a
network of interconnecting insulated conduits 115, a distribution
allocator 120, a working fluid distribution pump 130, and a
plurality of accessory heaters 150 thermally affixed to vehicle
accessories. The heat sources 110 may include one or more engine
and exhaust system mounted heat exchangers 111, steam
turbine-generator powered electrical fluid heaters 112, battery
powered fluid heaters 113, and steam heated heat exchangers 114.
The distribution allocator 120 includes a matrix of electrically
actuated valves 130 and a controller 140. The working fluid is
heated in the plurality of heat sources 110 and is then pumped to
the distribution allocator 120. The distribution allocator 120
routes the heated working fluid to the appropriate conduits 115 to
supply the plurality of accessories 150. The expended fluid is then
returned from the plurality of accessories 150, back to the
distribution allocator 120, from which it is returned to the heat
sources 110. Each of the distribution allocator valves 130,
operated by the controller 140, may be adjusted within the range
from fully open to fully closed.
[0050] The matrix of electrically actuated valves 130 may employ a
plurality of 4-port valves 400, as schematically drawn in FIG. 4,
to implement the necessary interconnectivity between fluid conduits
15S. The 4-port valve provides three states of connectivity between
the four ports. In state 1, as shown in FIG. 4, PORT A is connected
to PORT B and PORT D is connected to PORT C. In state 2, PORT A is
connected to PORT C and PORT B is connected to PORT D. In state 3,
PORT A is connected PORT D and PORT B is connected to PORT C. As
shown in cut-away in FIG. 4, the 4-port valve 400 comprises an
circular outer housing shell 420 having 4 pass-through fluid ports;
PORT A 430, PORT B 440, PORT C 450, and PORT D 460. An inner valve
body 410 is mounted inside the outer housing shell 420, so that it
can rotate about the center axis 510. The contact surface between
the inner valve body 410 and the outer shell 420, does not allow
fluid to migrate between the surfaces but permits rotation. A
stepper motor (not shown), whose shaft connects to the inner valve
body 410 at its center axis 510, is mechanically configured to
rotate the inner valve body 410 relative to the outer shell 420.
Other methods of rotating the inner valve body may include an
non-stepper electric motor, manual actuator, pneumatic actuator and
hydraulic actuator. The inner valve body 410 comprises two isolated
straight-through fluid flow channels, channel 2-6 480, channel 4-8
500, and two isolated right angle channels, channel 1-7 470, and
channel 3-5 490. The mouths of each of the channels matches up with
the port opening when the inner valve body 410 is rotated into
alignment. The flow through the valve may be reduced by partially
aligning the channel mouth with the port opening. A position sensor
(not shown) is operatively configured to report the relative
position of the inner valve body 410 to the distribution allocator
120.
[0051] In an embodiment, sensors 160 may be thermally coupled to
the heat sources 110, accessories, and accessory heaters 150 and
operatively connected to report temperatures to the controller 120.
Additional sensors (not shown) may be used to report environmental
temperatures and other conditions to the controller 120. A feedback
loop may thereby be established to maintain desired temperatures
throughout the system.
[0052] Each of the accessories 150 may have a different dynamically
varying heat requirement. It is further recognized that each of the
heat sources 110 may have different time versus temperature
profiles and different heat capacities. The distribution allocator
120 may configure the valves 130 so as to match the requirements of
each accessory heater 150 with the most suitable heat exchanger 110
combinations.
[0053] In some cases, the working fluid temperature may be too high
for a given accessory heater 150. In that situation, the working
fluid may be diverted to an auxiliary cooling coil (not shown),
exposed to the outside environment, by means of additional
electrically operated valves within the distribution allocator
120.
[0054] Accessories that may be heated by the energy recovery system
are described. For all applications, the working fluid is selected
to remain liquid over the temperature ranges to be encountered.
Suitable working fluids may comprise anti-freeze liquids such as
alcohol, methanol, ethylene glycol, propylene glycol, organic acid
technology anti-freeze solutions and mixtures of these liquids
and/or water.
[0055] A first accessory may be a windshield de-icer that is
schematically pictured in FIG. 5. The windshield 200 is formed of a
plate of safety glass 210 with fluid flow channels 220 located in a
plane parallel to the glass surface. The channels 220 are
interconnected so as to provide a continuous fluid flow path with
an input connection 230 and an output connection 240. In operation,
heated working fluid is pumped to the input connection 230, through
the continuous fluid flow path and out the output connection 240
from which it is returned.
[0056] A second accessory may be a windshield wiper heater. A
windshield wiper blade 300, shown in a cutaway view in FIG. 6, is
configured to have a fluid flow channel 310 running the length of
the blade and back. The input and output of the channel are
connected via flexible tubes back to the working fluid supply
lines. In operation, when required, heated working fluid is pumped
through the channel 310 thereby warming the windshield wiper blade.
Optionally the blade may include thermal conductive material 320
within the shell 330 of the wiper blade to allow for better
conduction to the wiper blade. In another embodiment, the wiper
blade has a recessed portion 340 in its construction with thermal
conductive material 320 therein. In such embodiment, the contact
edge 350 the wiper blade (e.g. the rubber of the blade) contacts
the window, while the recessed portion does not. Thus, the thermal
conductive material 320 may conduct heat into the recess. For
example, the wiper blade may be a V-shaped when viewed from the
windshield side, with the thermal conductive material 320 being
spaced from the windshield.
[0057] In another embodiment, heated working fluid may also be used
to heat the windshield washer fluid holding tank thereby warming
the windshield washer fluid and improving its effectiveness during
cold weather. For example, the washer fluid housing may be bathed
in the heated solution or a conduit may run therethrough which
contains the heated solution.
[0058] A third accessory may be an electric motor bearing heater.
Typically, a vehicle employs many small electric motors to power
various functions such as fluid pumps, power windows and power
antennas, and engine cooling fans. Each of these electric motors
has bearings that must remain lubricated during operation. Under
cold weather conditions, many lubricants exhibit reduced
performance. In an embodiment of the energy recovery system, heated
working fluid is used to warm the electric motor bearings, thereby
restoring desirable lubricant properties and resulting in improved
motor performance and extending motor life. A fluid flow channel is
formed in the bearing housing with an input port and an output port
connected to external conduits that supply and return the working
fluid.
[0059] A fourth accessory may be contact heating in the passenger
compartment. Currently, most vehicles employ blown air to heat the
passenger compartment. Some vehicles additionally provide
electrical heating elements in the passenger seats. Under extremely
cold conditions, especially when the passenger compartment is not
sealed, hot air system may not be effective. In an embodiment of
the energy recovery system, heated working fluid may be circulated
through fluid flow channels embedded in passenger seats, floor
boards and any other surfaces that the operator normally contacts
during vehicle operation. Sensors, connected to the distribution
allocator 120, may be used to determine allocation requirements.
The distribution allocator 120 may dynamically redistribute the
fluid based on vehicle occupancy thereby minimizing heat waste.
[0060] A fifth accessory may be a heater for the vehicle's storage
battery. The capacity and performance of lead-acid and other
storage batteries degrades at lower temperatures. In an embodiment,
heated working fluid may be circulated through fluid flow channels
in proximity to the outer surface of the battery case whereby a
more favorable operating temperature may be maintained. This
embodiment is of special significance to hybrid vehicles where
propulsion is supplied in part by energy stored in rechargeable
storage batteries. In a further embodiment, the fluid flow channels
may be incorporated into the battery structure to improve the
efficiency of the heat transfer. Temperature sensors may also be
incorporated into the battery to provide feedback to the
distribution allocator 120.
[0061] A sixth accessory is a temperature-maintaining compartment
within the vehicle for holding food, beverage, medical supplies or
similar items where preservation of the item's temperature is
desirable. The maintenance of temperature may fully automatic and
not require manual control. The compartment may be an thermally
insulated container having an access door which substantially
maintains the thermal insulation from the outside environment. The
interior walls of the compartment incorporate a continuous fluid
conduit, having an input port and an output port. The input and
output ports may be connected, via insulated conduits, to the
distribution allocator 120. In operation, an item(s) is placed
within the compartment and the door is closed. Sensors inside the
compartment, may detect the door closure and may immediately
measure the temperature of the item(s). The measured temperature
may be reported to the distribution allocator 120 which may
determine whether heat must be added or subtracted from the
interior of the compartment to maintain the item temperature. If
heat addition is required, heated fluid may be supplied from the
heat sources via the distribution allocator 120. If heat
subtraction is required cooled fluid is supplied from a cooling
unit via the distribution allocator 120. The cooling unit may be a
gas-absorption refrigeration unit powered by heated working fluid
provided by the distribution allocator 120. A gas-absorption
refrigeration unit is a refrigerator that utilizes a heat source to
provide the energy needed to drive the cooling system rather than
being dependent on electricity to run a compressor.
[0062] A seventh accessory is a temperature controlled jacket
configured as a cup holder in the vehicle. The temperature
controlled jacket incorporates a fluid flow channel within its
walls, through which fluid at a desired temperature may be
circulated. A mechanical fluid flow valve may be actuated
automatically when the cup is placed in the jacket. The flow of the
fluid may further be regulated by a thermostatically controlled
valve whereby the desired cup temperature may be maintained.
[0063] A eighth accessory is a heated door lock and door handle.
The door lock and door handle may incorporate a fluid conduit that
is thermally coupled to moving components of the respective locks
and handles. It is recognized that freezing of these components
often occurs during periods of vehicle non-use. In this situation,
where the engine has been shut down for an extended period of time,
heated fluid from the energy recovery system may not be available.
In an embodiment, an auxiliary insulated holding tank (not shown),
connected to the distribution allocator 120, may contain fluid
which was previously heated and stored. The auxiliary insulated
holding tank may incorporate double wall construction with a sealed
evacuated space therebetween to improve heat preservation. Flow of
the heated fluid through the respective door handles and locks may
be initiated by a control actuated from a location external to the
vehicle. In a further embodiment, an analogous approach may be
taken to de-icing frozen brake system components. The concept of
the auxiliary insulated holding tank may be applied to any or all
of the accessories disclosed in this specification.
STATEMENT REGARDING PREFERRED EMBODIMENTS
[0064] While the invention has been described with respect to
preferred embodiments, those skilled in the art will readily
appreciate that various changes and/or modifications can be made to
the invention without departing from the spirit or scope of the
invention as defined by the appended claims.
* * * * *