U.S. patent application number 11/207966 was filed with the patent office on 2007-10-25 for method and apparatus for loading a source gas into a cavitation medium.
This patent application is currently assigned to Impulse Devices, Inc.. Invention is credited to Ross Alan Tessien.
Application Number | 20070248470 11/207966 |
Document ID | / |
Family ID | 38320828 |
Filed Date | 2007-10-25 |
United States Patent
Application |
20070248470 |
Kind Code |
A1 |
Tessien; Ross Alan |
October 25, 2007 |
Method and apparatus for loading a source gas into a cavitation
medium
Abstract
A cavitation system and method of use for loading the cavitation
medium with a source gas, e.g., a reactant, prior to cavitation is
provided. The cavitation system includes a cavitation chamber with
suitable cavitation drivers and a pressurized gas source coupled to
the chamber. A valve interposed between the source gas and the
cavitation chamber controls the reactant loading process. In
another aspect, a vacuum system is coupled to the cavitation system
for use during degassing. The vacuum system may include a cold
trap. Preferably multiple valves are used to couple/de-couple the
vacuum system and the gas source to the cavitation system when
required, for example as a means of protecting associated pressure
gauges. In another aspect, the cavitation chamber and the
cavitation medium fill reservoir as well as any coupling conduits
in which the cavitation fluid is expected to flow are heated to a
temperature greater than the melting temperature of the intended
cavitation medium. Preferably the system components that must be
heated are located within an oven. Alternately the desired
temperature can be reached using localized heaters.
Inventors: |
Tessien; Ross Alan; (Nevada
City, CA) |
Correspondence
Address: |
PATENT LAW OFFICE OF DAVID G. BECK
P. O. BOX 1146
MILL VALLEY
CA
94942
US
|
Assignee: |
Impulse Devices, Inc.
Grass Valley
CA
|
Family ID: |
38320828 |
Appl. No.: |
11/207966 |
Filed: |
August 19, 2005 |
Current U.S.
Class: |
417/105 |
Current CPC
Class: |
G01N 2013/0266 20130101;
B01F 11/0266 20130101 |
Class at
Publication: |
417/105 |
International
Class: |
F04F 1/04 20060101
F04F001/04 |
Claims
1. A cavitation system comprising: a cavitation chamber; a
cavitation medium within said cavitation chamber; at least one
cavitation driver coupled to said cavitation chamber; degassing
means coupled to said cavitation chamber; a first valve interposed
between said cavitation chamber and a pressure bleeding conduit; a
second valve interposed between said cavitation chamber and said
degassing means; a pressurized gas source coupled to said
cavitation chamber; and a third valve interposed between said
pressurized gas source and said cavitation chamber.
2. The cavitation system of claim 1, further comprising a pressure
regulator interposed between said third valve and said cavitation
chamber.
3. The cavitation system of claim 1, further comprising a pressure
regulator interposed between said pressurized gas source and said
third valve.
4. The cavitation system of claim 1, wherein said first and second
valves comprise a single three-way valve.
5. The cavitation system of claim 1, wherein said degassing means
further comprises a vacuum pump.
6. The cavitation system of claim 1, further comprising a cold trap
interposed between said degassing means and said cavitation
chamber.
7. The cavitation system of claim 1, further comprising a
cavitation medium filling reservoir coupled to said cavitation
system.
8. The cavitation system of claim 1, further comprising means for
heating said cavitation chamber to a temperature greater than a
melting temperature corresponding to said cavitation medium.
9. The cavitation system of claim 8, wherein said heating means is
an oven.
10. The cavitation system of claim 7, further comprising means for
heating said cavitation chamber and said cavitation medium filling
reservoir to a temperature greater than a melting temperature
corresponding to said cavitation medium.
11. The cavitation system of claim 10, wherein said heating means
is an oven.
12. The cavitation system of claim 1, further comprising a fourth
valve interposed between a second pressure bleeding conduit and
said pressurized gas source.
13. The cavitation system of claim 12, wherein said third and
fourth valves comprise a single three-way valve.
14. A method of preparing a cavitation medium contained within a
cavitation system for cavitation, the method comprising the steps
of: filling a cavitation chamber within said cavitation system with
a quantity of the cavitation medium; sealing the cavitation system;
degassing the cavitation medium within the cavitation system with a
degassing system; sealing off the degassing system from the
cavitation system; pressurizing the cavitation system with a source
gas; and cavitating the cavitation medium within the cavitation
chamber, wherein said cavitating step at least partially depletes
the cavitation medium of said source gas.
15. The method of claim 14, wherein prior to the step of cavitating
the cavitation medium, the method further comprises the steps of:
sealing off the source gas from the cavitation system; bleeding at
least some of the pressure out of the cavitation system; degassing
the cavitation medium within the cavitation system with the
degassing system; sealing off the degassing system from the
cavitation system; and pressurizing the cavitation system with the
source gas.
16. The method of claim 14, further comprising the step of heating
said cavitation chamber.
17. The method of claim 16, wherein said step of heating said
cavitation chamber is performed to a temperature greater than a
melting temperature corresponding to the cavitation medium.
18. The method of claim 14, wherein said filling step partially
fills said cavitation chamber with the cavitation medium.
19. The method of claim 14, wherein said filling step fills said
cavitation chamber with the cavitation medium.
20. The method of claim 14, wherein said source gas contains a
reactant and wherein said cavitating step at least partially
depletes the cavitation medium of said reactant.
21. The method of claim 14, further comprising the step of
evacuating the cavitation system prior to performing said
cavitation medium filling step.
22. The method of claim 14, said degassing step further comprising
the step of cavitating the cavitation medium to remove gas from the
cavitation medium.
23. The method of claim 14, wherein the step of cavitating the
cavitation medium within the cavitation chamber further comprises
the step of bleeding the cavitation system pressure.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to cavitation
processes and, more particularly, to a method and apparatus for
loading a source gas into a cavitation system.
BACKGROUND OF THE INVENTION
[0002] Sonoluminescence is a well-known phenomena discovered in the
1930's in which light is generated when a liquid is cavitated.
Although a variety of techniques for cavitating the liquid are
known (e.g., spark discharge, laser pulse, flowing the liquid
through a Venturi tube), one of the most common techniques is
through the application of high intensity sound waves.
[0003] In essence, the cavitation process consists of three stages;
bubble formation, growth and subsequent collapse. The bubble or
bubbles cavitated during this process absorb the applied energy,
for example sound energy, and then release the energy in the form
of light emission during an extremely brief period of time. The
intensity of the generated light depends on a variety of factors
including the physical properties of the liquid (e.g., density,
surface tension, vapor pressure, chemical structure, temperature,
hydrostatic pressure, etc.) and the applied energy (e.g., sound
wave amplitude, sound wave frequency, etc.).
[0004] It is generally recognized that during the collapse of a
cavitating bubble extremely high temperature plasmas are developed,
leading to the observed sonoluminescence effect. This phenomena is
at the heart of a considerable amount of research as scientists and
engineers attempt to both completely characterize the phenomena and
find applications for it. Noted applications include sonochemistry,
chemical detoxification, ultrasonic cleaning and nuclear
fusion.
[0005] U.S. Pat. No. 4,333,796 discloses a cavitation chamber
comprised of a refractory metal such as tungsten, titanium,
molybdenum, rhenium or some alloy thereof. Acoustic energy is
supplied to the liquid (e.g., lithium or an alloy thereof) within
the chamber by six metal acoustic horns coupled to transducers. The
tips of the horns project into the chamber while the rearward
portion of each horn is coupled to a heat exchanger system, the
heat exchanger system withdrawing heat generated by the reactions
within the chamber. The inventors note that by removing heat in
this manner, the liquid remains within the chamber, thus avoiding
the need to pump the chamber liquid. In one disclosed embodiment,
the source (i.e., deuterium) is introduced into the cavitation
medium through a conduit attached to the top of the chamber, the
concentration of the source being controlled by the dissociation
pressure over the surface of the host liquid. In an alternate
disclosed embodiment, an external processing system with a
combination pump and mixer removes deuterium and tritium gases
released from the cavitation zone and trapped within the chamber or
tritium gases trapped within the Li-blanket surrounding the chamber
and then reintroduces the previously trapped deuterium and tritium
into the cavitation zone via a conduit coupled to the cavitation
chamber. Additional deuterium may also be introduced into the
mixer.
[0006] U.S. Pat. No. 4,563,341, a continuation-in-part of U.S. Pat.
No. 4,333,796, discloses a slightly modified, cylindrical
cavitation chamber. The chamber is surrounded by an external
heating coil which allows the liquid within the chamber to be
maintained at the desired operating temperature. The system is
degassed prior to operation by applying a vacuum through a duct
running through the cover of the chamber. During operation, the
inventor notes that graphite, dissolved in the host liquid metal,
is converted to diamond. The diamond-rich host material is removed
via an outlet duct adjacent to the bottom of the chamber and
graphite-rich host material is removed via an outlet duct adjacent
to the upper end of the chamber. Additional host material and
graphite are added by lowering rods comprised of the host material
and graphite, respectively, into the heated chamber.
[0007] U.S. Pat. No. 5,659,173 discloses a sonoluminescence system
that uses a transparent spherical flask fabricated from Pyrex.RTM.,
Kontes.RTM., quartz or other suitable glass and ranging in size
from 10 milliliters to 5 liters. The inventors disclose that
preferably the liquid within the flask is degassed and the flask is
sealed prior to operation. In one disclosed embodiment, the
cavitation chamber is surrounded by a temperature control system,
thus allowing the liquid within the chamber to be cooled to a
temperature of 1.degree. C. Bubbles are introduced into the
cavitation fluid using a variety of techniques including dragging
bubbles into the fluid, for example with a probe, and localized
boiling.
[0008] U.S. Pat. No. 5,858,104 discloses a shock wave chamber
partially filled with a liquid. The remaining portion of the
chamber is filled with gas which can be pressurized by a connected
pressure source. Acoustic transducers mounted in the sidewalls of
the chamber are used to position an object within the chamber while
another transducer delivers a compressional acoustic shock wave
into the liquid. A flexible membrane separating the liquid from the
gas reflects the compressional shock wave as a dilatation wave
focused on the location of the object about which a bubble is
formed.
[0009] U.S. Pat. No. 5,968,323 discloses a cavitation chamber
filled with a low compressibility liquid such as a liquid metal,
the chamber enclosed within a temperature controlled container. A
sealed fluid reservoir is also enclosed within the temperature
controlled container, the reservoir connected to the bottom of the
cavitation chamber by a pipe. By pressurizing or evacuating the
reservoir, fluid can be forced into or withdrawn from the
cavitation chamber. Fluid flow into or out of the chamber is aided
by a vacuum pump and a pressurized gas source coupled to the top of
the cavitation chamber. The system includes two material delivery
systems for introducing materials or mixtures of materials into the
chamber. One of the delivery systems is coupled to the bottom of
the chamber and is intended for use with materials of a lower
density than that of the cavitation liquid, thus causing the
material to float upwards. The second delivery system is coupled to
the top of the chamber and is intended for use with materials of a
higher density than that of the cavitation liquid, thus causing the
material to sink once introduced into the chamber.
[0010] PCT Application No. US02/16761 discloses a nuclear fusion
reactor in which at least a portion of the liquid within the
reactor is placed into a state of tension, this state of tension
being less than the cavitation threshold of the liquid. The liquid
preferably includes enriched deuterium or tritium, the inventors
citing deuterated acetone as an exemplary liquid. In at least one
disclosed embodiment, acoustic waves are used to pretension the
liquid. After the desired state of tension is obtained, a
cavitation initiation source, such as a neutron source, nucleates
at least one bubble within the liquid, the bubble having a radius
greater than a critical bubble radius. The nucleated bubbles are
then imploded, the temperature generated by the implosion being
sufficient to induce a nuclear fusion reaction.
[0011] PCT Application No. CA03/00342 discloses a nuclear fusion
reactor in which a bubble of fusionable material is compressed
using an acoustic pulse, the compression of the bubble providing
the necessary energy to induce nuclear fusion. The nuclear fusion
reactor is spherically shaped and filled with a liquid such as
molten lithium or molten sodium. A pressure control system is used
to maintain the liquid at the desired operating pressure. To form
the desired acoustic pulse, a pneumatic-mechanical system is used
in which a plurality of pistons associated with a plurality of air
guns strike the outer surface of the reactor with sufficient force
to form a shock wave within the liquid in the reactor. In one
disclosed embodiment, the spherical reactor is coupled to a fluid
flow circuit in which a pump and a valve control the flow of fluid.
A reservoir containing a fusionable material, preferably in gaseous
form, is in communication with the fluid flow circuit. When
desired, a bubble of the fusionable material, preferably
encapsulated in a spherical capsule, is released from the reservoir
and into the fluid flow circuit, which then injects the bubble into
a port at the bottom of the chamber.
[0012] Co-pending U.S. patent application Ser. No. 11/001,720,
filed Dec. 1, 2004, discloses a system for circulating cavitation
fluid within a closed-loop fluid circulatory system coupled to the
cavitation chamber. Cavitation fluid can be circulated throughout
the system before, during or after cavitation chamber operation. As
disclosed, a network of conduits couples the cavitation chamber to
a cavitation fluid reservoir and at least one external fluid pump.
Manipulation of various valves within the conduit network allows
the cavitation fluid to either be pumped from the reservoir into
the cavitation chamber or from the cavitation chamber into the
reservoir. The disclosed system provides a means of draining and/or
filling the cavitation chamber with minimal, if any, exposure of
the cavitation fluid to the outside environment.
[0013] Although a variety of sonoluminescence systems have been
designed, they do not provide an efficient system for introducing a
source, e.g., a reactant, into the cavitation medium. Accordingly,
what is needed is a cavitation system that can be used for source
loading. The present invention provides such a system.
SUMMARY OF THE INVENTION
[0014] The present invention provides a system and method of use
for a cavitation system in which a source gas, e.g., a reactant, is
loaded into the cavitation medium prior to cavitation. The
cavitation system of the invention includes a cavitation chamber
with suitable cavitation drivers and a pressurized gas source
coupled to the chamber. A valve interposed between the source gas
and the cavitation chamber controls the loading process in which
the cavitation medium is loaded with the desired reactant (i.e.,
the source gas). In another aspect of the invention, a vacuum
system is coupled to the cavitation system for use during degassing
procedures. The vacuum system may include a cold trap. Preferably
multiple valves are used to couple/de-couple the vacuum system and
the gas source to the cavitation system when required, for example
as a means of protecting pressure and vacuum gauges attached to the
system.
[0015] In one embodiment of the invention, the cavitation medium
(e.g., metal, salt) has a melting temperature higher than the
ambient temperature. In order to accommodate such a medium, the
cavitation chamber and the cavitation medium fill reservoir as well
as any coupling conduits in which the cavitation fluid is expected
to flow are heated to a temperature greater than the melting
temperature of the intended cavitation medium. Preferably in this
embodiment the system components that must be heated are located
within an oven. Alternately the desired temperature can be reached
using localized heaters to heat the cavitation chamber, fill
reservoir and those portions of the conduits through which the
cavitation fluid must pass.
[0016] In another embodiment of the invention, a method of loading
a cavitation medium with a source, e.g., reactant, is provided. The
cavitation system is first filled with sufficient cavitation fluid
to fill the cavitation chamber to the desired operating capacity
(e.g., full, partially full). After filling to the desired level,
the system is sealed and degassed. Cavitation may be used to aid
the degassing procedure. The cavitation medium is then loaded with
the desired source, e.g., reactant, by pressurizing the system with
the desired gas. The cavitation process is then initiated in the
cavitation chamber. Depending upon the melting temperature of the
cavitation medium, this embodiment of the invention may also
include the step of heating the cavitation medium as well as all
components through which the cavitation medium flows.
[0017] A further understanding of the nature and advantages of the
present invention may be realized by reference to the remaining
portions of the specification and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an illustration of the primary components of a
system configured in accordance with the invention;
[0019] FIG. 2 illustrates the steps performed during use of the gas
loading system shown in FIG. 1;
[0020] FIG. 3 is an illustration of a system similar to that shown
in FIG. 1, showing an alternate means of filling the cavitation
chamber with cavitation fluid;
[0021] FIG. 4 is an illustration of a system similar to that shown
in FIG. 1, showing an alternate means of filling the cavitation
chamber with cavitation fluid;
[0022] FIG. 5 is an illustration of the system of FIG. 3 with the
inclusion of an oven surrounding the cavitation chamber and fill
reservoir;
[0023] FIG. 6 is an illustration of the system of FIG. 4 with the
inclusion of an oven surrounding the cavitation chamber and fill
reservoir;
[0024] FIG. 7 is an illustration of the system of FIG. 3 with the
inclusion of heaters surrounding the cavitation chamber, fill
reservoir and coupling conduits; and
[0025] FIG. 8 illustrates the steps performed during use of the gas
loading system shown in FIGS. 5-7.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
[0026] FIG. 1 is an illustration of one embodiment of the
invention. System 100 includes a cavitation chamber 101 in which
the desired cavitation processes, for example cavitation driven
reactions, are performed. Cavitation chamber 101 is coupled to the
source, e.g., reactant, loading system via conduit 103.
[0027] In illustrated system 100 as well as at least one preferred
embodiment of the invention, cavitation chamber 101 is a spherical
chamber. It will be appreciated, however, that the invention is not
limited to spherical chambers, rather chamber 101 can utilize any
chamber design which is suitable for the intended cavitation
process. Examples of other configurations include cylindrical
chambers, hourglass-shaped chambers, conical chambers, cubical
chambers, rectangular chambers, irregularly-shaped chambers, etc.
One method of fabricating chamber 101 is described in detail in
co-pending U.S. patent application Ser. No. 10/925,070, filed Aug.
23, 2004, entitled Method of Fabricating a Spherical Cavitation
Chamber, the entire disclosure of which is incorporated herein for
any and all purposes. Examples of hourglass-shaped chambers are
provided in co-pending U.S. Patent application Ser. No. 11/140,175,
filed May 27, 2005, entitled Hourglass-Shaped Cavitation Chamber,
and Ser. No. 11/149,791, filed Jun. 9, 2005, entitled
Hourglass-Shaped Cavitation Chamber with Spherical Lobes, the
entire disclosures of which are incorporated herein for any and all
purposes. An example of a cylindrical cavitation chamber is
provided in co-pending U.S. patent application Ser. No. 11/038,344,
filed Jan. 18, 2005, entitled Fluid Rotation System for a
Cavitation Chamber, the entire disclosure of which is incorporated
herein for any and all purposes.
[0028] Chamber 101 can be fabricated from any of a variety of
materials, depending primarily upon the desired operating pressure
and temperature of the chamber and system. Preferably the selected
material is machinable, thus simplifying fabrication, and corrosion
resistant, thus allowing the chamber to be used repeatedly with a
variety of liquids. Typically a metal, for example 17-4
precipitation hardened stainless steel, is used for chamber
101.
[0029] The selected dimensions of chamber 101 depend primarily on
the intended use of the chamber, although the cost of the
cavitation fluid, chamber fabrication issues, operating temperature
and cavitation driver capabilities also influence the preferred
dimensions of the chamber for a specific process. In general, small
chambers are preferred for situations in which it is desirable to
limit the amount of the cavitation medium or in which driver input
energy is limited while large chambers (e.g., 10 inches or greater)
are preferred as a means of simplifying experimental set-up and
event observation or when high energy reactions are being driven
within the chamber. Thick chamber walls are preferred in order to
accommodate high pressures.
[0030] Conduit 103 allows the system to be coupled to a vacuum
system for evacuation and coupled to a pressurized gas system for
supplying the desired gas for loading the cavitation medium.
Although not preferred, it should be understood that the gas
loading system and the degassing system (i.e., vacuum pump) can be
attached to system 100 (e.g., conduit 103) in separate locations.
Conduit 103 can also be used to fill the system with the cavitation
medium. Alternately a separate cavitation medium filling system can
be used as described in further detail below.
[0031] In the preferred embodiment, conduit 103 tees or splits into
two branches, conduit 105 leading to the vacuum system and conduit
107 leading to the gas loading system. A three-way valve 109 allows
the system to be coupled to the ambient atmosphere via conduit 111
or to vacuum pump 113. It will be appreciated that three-way valve
109 can be replaced with a pair of two-way valves (not shown).
Valve 115 provides a means for isolating the system from pump 113.
Preferably a trap 117 insures that cavitation fluid is not drawn
into vacuum pump 113 or vacuum gauge 119. Preferably trap 117 is
cooled so that any cavitation medium entering the trap solidifies.
Typically at least one vacuum gauge 119 is used to provide an
accurate assessment of the system pressure. Once the cavitation
system is pressurized, prior to re-coupling the system to either
vacuum gauge 119 or vacuum pump 113, the cavitation system pressure
is bled down to an acceptable level using three-way valve 109.
[0032] A high pressure gas source 125 is coupled to the cavitation
system. Preferably a three-way valve 121 allows high pressure gas
source 125 to be coupled to the system or to the ambient atmosphere
via conduit 123. It will be appreciated that three-way valve 121
can be replaced with a pair of two-way valves (not shown). Conduit
123 and the associated valve allows the pressure to be bled from
the high pressure system prior to changing source 125 or otherwise
working on the high pressure system. A pressure regulator 127 is
used to control the output pressure of source 125. Valve 129
controls the output of source 125. Typically at least one pressure
gauge 131 is used to monitor the system pressure.
[0033] FIG. 2 illustrates the primary steps performed during the
use of the gas loading system of the invention. Initially the
system is tested for leaks using a two step process (step 201).
First, the entire system is evacuated using vacuum pump 113 in
order to verify that the system does not have any leaks while under
vacuum. Second, the entire system is pressurized, for example using
a high pressure nitrogen or helium source. The high pressure gas
source which is used during testing can be attached where source
gas 125 is typically attached, or separately coupled to system 100.
Typically system 100 is tested at least at the highest expected
pressure (e.g., operating pressure, gas loading pressure), on the
order of 500 to 1000 psi in the preferred embodiment, and at the
desired operating temperature.
[0034] If the system does not exhibit any leaks while evacuated or
pressurized, or after any leaks have been fixed, it is then filled
with the cavitation medium (step 203). The system is filled with
sufficient cavitation medium to fill cavitation chamber 101 to the
desired operating level. It will be appreciated that the operating
level for chamber 101 is based on obtaining the most efficient
cavitation action. For example, while a spherical chamber (e.g.,
the chamber shown in FIG. 1) may be most efficiently operated when
it is completely full, a vertically aligned cylindrical chamber may
operate most efficiently when it is not completely full, thus
providing a free cavitation liquid surface at the top of the
chamber.
[0035] System 100 can be filled, for example, via conduit 111.
Alternately system 100 can be coupled to a filling or a
filling/degassing system. For example, in the system illustrated in
FIG. 3, a different conduit 301 and filling reservoir 303 is used
for system filling while in the system illustrated in FIG. 4 a
filling reservoir 401 is coupled to cavitation chamber 101 with a
circulatory system 403.
[0036] In the system illustrated in FIG. 3, conduit 301 is coupled
to conduit 103 via a three-way valve 305. It will be understood
that reservoir 303 could also be coupled to chamber 101 via a
different conduit, for example conduit 111 or conduit 123.
Alternately, conduit 103 can be disconnected from chamber 101 and
conduit 301 connected to chamber 101 for filling, and then, once
the system is filled to the desired level, reversed (i.e.,
re-coupling conduit 103 to chamber 101). Regardless of the method
used to couple reservoir 303 to system 101, preferably the system
is evacuated prior to filling, thus causing the cavitation medium
to be drawn into the system (i.e., utilizing ambient air pressure
to provide the pressure to fill the system).
[0037] In the system illustrated in FIG. 4, preferably a
circulation pump 405 is used to either pump the cavitation medium
into chamber 101 from reservoir 401, or pump the cavitation medium
from chamber 101 into reservoir 401. Although preferably a two-way
pump is used, in an alternate embodiment a pair of pumps is used,
thus allowing cavitation fluid to be pumped into or out of the
cavitation chamber. In the illustrated system, a two-way valve 407
is used to either couple cavitation chamber 101 to reservoir 401 or
to the vacuum/source filling system. Preferably the system includes
a pair of valves 409, thus allowing easy isolation of the
cavitation chamber.
[0038] After system 100 is filled, the system is sealed and
degassed using vacuum pump 113 (step 205). This step typically
takes between 30 and 60 minutes, depending primarily upon the
capacity of pump 113, the volume of chamber 101, and the vapor
pressure of the cavitation fluid. In general, the system is pumped
down to the limits of the vacuum pump (e.g., less than 1 mm of
mercury for liquid metals) or to the vapor pressure of the
liquid.
[0039] After degassing step 205, a determination is made as to
whether additional degassing is required (step 207). In general,
the amount of degassing that is required depends on the sensitivity
of the reactants to the presence of oxygen and nitrogen (i.e., the
greater the sensitivity to oxygen and nitrogen, the greater the
need for degassing). If additional degassing is warranted,
preferably cavitation using a cavitation driver(s) coupled to
chamber 01 is used to tear vacuum cavities within the cavitation
medium (step 209). As the newly formed cavities expand, gas from
the fluid that remains after the initial degassing step enters into
the cavities. During cavity collapse, however, not all of the gas
re-enters the fluid. Accordingly a result of the cavitation process
is the removal of dissolved gas from the cavitation fluid via
rectified diffusion and the generation of bubbles. Preferably the
cavitation degassing step is performed repeatedly (step 211) until
all of the cavitation medium is sufficiently degassed.
[0040] The cavitation fluid is preferably degassed within chamber
101 as described above. It should be appreciated, however, that
degassing can be performed within the reservoir (e.g., reservoir
401) prior to filling chamber 101 with the cavitation fluid. In
this instance if additional degassing via cavitation is required,
either chamber 101 can be filled after the initial degassing step
or the degassing via cavitation step (i.e., step 209) can be
performed within the reservoir (e.g., reservoir 401), assuming that
at least one cavitation driver is coupled to the reservoir (not
shown). This approach is not, however, preferred as it does not
eliminate the need for drivers 133 which are required for the
desired cavitation process.
[0041] As previously described, cavitation as a means of degassing
the fluid is typically performed within cavitation chamber 101
using one or more cavitation drivers 133. Clearly the invention is
not limited to a specific number, type or location of driver.
Examples of suitable drivers are given in co-pending U.S. patent
application Ser. No. 10/931,918, filed Sep. 1, 2004, entitled
Acoustic Driver Assemblyfor a Spherical Cavitation Chamber; Ser.
No. 11/123,388, filed May 5, 2005, entitled Acoustic Driver
Assembly With Recessed Head Mass Contact Surface; and Ser. No.
11/068,080, filed Feb. 28, 2005, entitled Hydraulic Actuated
Cavitation Chamber, the disclosures of which are incorporated
herein in their entirety for any and all purposes. Preferably for
high vapor pressure liquids, prior to optional step 209 the use of
vacuum pump 113 is temporarily discontinued, for example by closing
valve 115 and turning off the pump, thereby minimizing the loss of
cavitation medium through boiling. For low vapor pressure liquids
such as liquid metals, vacuum pump 113 can be operated
continuously. After the fluid within chamber 101 is cavitated for a
period of time, typically for at least 5 minutes and preferably for
more than 30 minutes, the newly created bubbles float to the top of
the chamber due to their buoyancy. The gas removed from the fluid
during this step is periodically removed from the cavitation system
using vacuum pump 113. Typically the vacuum pump is only used after
there has been a noticeable increase in pressure within system 100,
preferably an increase of at least 0.2 psi over the vapor pressure
of the cavitation fluid, alternately an increase of at least 0.02
psi over the vapor pressure of the cavitation fluid, or alternately
an increase of a couple of percent of the vapor pressure.
Preferably the use of cavitation as a means of degassing the
cavitation fluid is continued until the amount of dissolved gas
within the cavitation fluid is so low that the fluid will no longer
cavitate at the same cavitation driver power.
[0042] Once system 100 is sufficiently degassed via step 205 and,
if desired, optional step 209, system 100 is sealed off from the
vacuum system, for example using valve 109 (step 213), thereby
protecting sensitive vacuum gauge 119. Then system 100 is
pressurized with the desired source (i.e., reactant) gas 125 to the
desired pressure in order to load the cavitation medium with the
source gas (step 215). In one preferred embodiment, the desired
system pressure is between 500 and 1000 psi and source gas 125 is
deuterium gas. If desired, source gas 125 can be a mixture of
gases.
[0043] After completion of step 215, cavitation drivers 133 are
used to cavitate the cavitation medium contained within chamber
101. In a preferred embodiment, however, the concentration of
non-source gas in the cavitation medium is further decreased by
isolating the cavitation system from the high pressure source and
repeating the degassing steps. Once again step 209 is optional.
After this degassing step, system 100 is once again sealed off from
the vacuum system and then pressurized with source gas 125.
[0044] At this point the cavitation system is ready to perform the
desired cavitation reactions within chamber 101. Accordingly the
cavitation medium within chamber 101 which has been loaded with
source gas 125 is cavitated using driver(s) 133, the high intensity
cavitation driven implosions within the cavitation medium driving
the desired reactions (step 217).
[0045] As the cavitation driven reactions take place and bubbles
are formed and cavitated within the medium, the cavitating medium
slowly becomes depleted of source gas 125. After the cavitation
medium has been sufficiently depleted of source gas 125, either
experiments are terminated (step 219) or the cavitation fluid must
be reloaded (step 215). If the reaction products are gaseous, then
preferably the medium is degassed (step 205) prior to reloading the
system.
[0046] During cavitation step 217, the inventor has found that
slowly bleeding system 100, for example by opening valve 121 to
conduit 123 and lowering the pressure at a rate of approximately 10
psi per hour, leads to improved bubble formation (optional step
221).
[0047] It should be understood that cavitation system 100 is not
limited to one specific cavitation fluid. The primary limitation
placed on the cavitation medium is the temperature capabilities of
system 100 since the system, as shown, is only capable of operating
at ambient temperature. In order to use the system for higher
temperature applications, in particular those in which the
cavitation medium must be heated in order to change phases from
solid to liquid, at least a portion of the cavitation system must
be heated. To simplify the design and fabrication of a system
capable of operating at elevated temperatures, preferably the
melting point of the cavitation media is relatively low (e.g.,
mercury or a cerro metal such as cerrobend). Higher melting point
metals or salts can be used if the system is capable of operating
at or above the melting point of the desired metal or salt.
[0048] As previously noted, the present apparatus and source
loading method can be used with liquid metals, including those
metals that have a melting point higher than the ambient
temperature. FIG. 5 is an illustration of the system shown in FIG.
3 modified for use with such cavitation media. Specifically,
chamber 101, reservoir 303, conduit 301 and a portion of conduit
103 are all placed within an oven 501. Conduit 103 passes through
the wall of oven 501, thus allowing vacuum pump 113, high pressure
gas source 125, regulator 127, and pressure gauges 119/131 to all
be maintained at ambient temperature. FIG. 6 is an illustration of
a system similar to that shown in FIG. 4, modified such that
chamber 101, reservoir 401, conduit 403 and a portion of conduit
103 are all placed within an oven 601. Preferably, as in the
embodiment illustrated in FIG. 5, vacuum pump 113, high pressure
gas source 125, regulator 127, and pressure gauges 119/131 are all
outside of the oven.
[0049] Although the inventor has found that the systems shown in
FIGS. 5 and 6 are the easiest method of consistently maintaining
the desired temperature throughout chamber 101, the fill reservoir
and the associated conduits, it is also possible to use localized
heaters. For example, the system shown in FIG. 7 is similar to that
shown in FIG. 5, except that oven 501 has been replaced with
localized heaters. Specifically, chamber 101 is surrounded by a
heater 701, reservoir 303 is surrounded by a heater 703, conduit
301 is surrounded/wrapped with a heater 705, valve 305 is
surrounded by a heater 707, and a portion of conduit 103 is
surrounded/wrapped with a heater 709. Similarly, oven 601 can be
replaced with localized heaters. It will be appreciated that during
system operation, drivers 133 will also heat the cavitation medium
contained within chamber 101, thereby lowering the heating
requirements placed on a localized chamber heater.
[0050] Regardless of the method of heating (i.e., oven, localized
heaters, etc.), in addition to heating chamber 101 it is necessary
to heat the initial cavitation fluid filling reservoir as shown in
the embodiments of FIGS. 5-7. Accordingly if the filling reservoir
is coupled to the system in a different location than shown (e.g.,
to conduit 111 or 123), the reservoir as well as any conduits used
to couple the reservoir to the system must be heated, at least
throughout the chamber filling procedure.
[0051] The use of the heated system as illustrated in FIGS. 5-7 is
similar to the approach previously outlined for the non-heated
system. However, as illustrated in FIG. 8, an additional system
heating step 801 is required. Preferably heating step 801 is
performed prior to, or concurrently with, system testing step 201,
thus insuring that the system does not have any vacuum or pressure
leaks even at the elevated operating temperature.
[0052] As will be understood by those familiar with the art, the
present invention may be embodied in other specific forms without
departing from the spirit or essential characteristics thereof.
Accordingly, the disclosures and descriptions herein are intended
to be illustrative, but not limiting, of the scope of the invention
which is set forth in the following claims.
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