Abstract: Systems and methods for achieving cavitation at high static pressures which may be used in acoustic applications and research such as in liquid metal resonators. Novel preparation and electroplating methods are disclosed to improve boundary layer conditions. A chemical cleaning loop for containment and treatment for oxide removal and to develop a dynamic system for chemically treating liquid metal disposed in a liquid metal loop is also described. A liquid metal handling loop for containment and treatment is provided to maintain cleanliness of bulk liquid metal.

Abstract: Systems and methods for treating small elongated fibrous and particles of certain materials, e.g., PTFE materials in a suspension are presented. In some instances, high-intensity ultrasound (or acoustical energy) is applied to a sample of the material, through a fluid coupling medium or suspension, to achieve a material transformation in the sample. In various embodiments, fibrillation of particles of PTFE or similar materials is accomplished, or the formation of extended structures of these materials is caused or enhanced. Also, the ability to separate long fiber samples by ultrasonic or acoustic cavitation action is provided.

Abstract: A system and method for loading gases or other soluble fuel or catalyst materials into a liquid cavitation medium such as a liquid metal, which may be cavitated under static pressure so as to cause a desired energetic reaction in the dissolved gaseous fuel substance at the cavitation sites. Examples of liquid cavitation media can include liquid metals such as liquid gallium, and examples of dissolved gaseous fuel substances can include deuterium. Sufficiently intense cavitation (for example carried out under high static pressures) may provide energetic reactions in the fuel that release subatomic particles therefrom such as neutrons. The present system and method may be used to load such gaseous fuels into other liquid metal systems, including systems that are non-cavitation-based or that cause cavitation in the liquid by means other than the acoustical drivers described in the preferred embodiments.

Abstract: A system including an ultrasonic resonance chamber containing a cavitation reaction chamber therein is described. In some embodiments, the resonance chamber or resonator comprises a spherical metal shell having fluid and other couplings and containing a first liquid that carries an acoustic field within the resonator. A second fluid or material that can flow within the reaction chamber or reactor is disposed at a location in the resonator so that the two fluids do not mix but the acoustic field in the resonator can generate cavitation inside the reactor to cause a desired transformation or reaction in the second fluid or material.

Abstract: A cavitation system in which a source gas, e.g., a reactant, is loaded into the cavitation medium prior to cavitation is provided. The cavitation system includes a cavitation chamber with suitable cavitation drivers and a cavitation medium reservoir, the chamber and reservoir being flexibly coupled together via a pair of conduits. The conduits can be fabricated from a plastic or, as is preferred for higher temperature liquids, a metal. Typically metal conduits are formed into a coil, thus providing the desired flexibility. Flexibility is required in order to allow the relative positions of the cavitation chamber and the cavitation medium reservoir to be varied.

Abstract: An hourglass-shaped cavitation chamber is provided. The chamber is comprised of two large spherical regions separated by a smaller cylindrical region. Coupling the regions are two transitional sections which are preferably smooth and curved. Although the chamber is preferably fabricated from a machinable material, such as a metal, it can also be fabricated from a fragile material, such as a glass. An acoustic driver assembly is incorporated within the chamber wall at one end of the cavitation chamber. The driver can be threadably coupled to the chamber or attached using an epoxy, diffusion bonding, brazing or welding. O-rings or other seals can be used to seal the driver to the chamber. The head surface of the driver assembly can be flush, recessed, or extended from the internal chamber surface. The head surface of the driver assembly can be flat or shaped. If desired, a second acoustic driver assembly can be incorporated within the chamber wall at the other end of the cavitation chamber.

Abstract: A system and method for treating biomass so as to convert the biomass into a useful form is provided. In some embodiments, the system and method allow treating a biomass mixed in a fluid medium in an acoustic resonator chamber. The chamber may be used to mix the biomass with other chemical agents or catalysts. The chamber is also coupled to one or more acoustical drivers to provide an acoustical (e.g., ultrasonic) field in the chamber, which can also be driven to cause acoustic cavitation in some embodiments. The acoustic resonator chamber may also be placed under static pressure to enhance a mechanical, acoustical, or chemical effect during processing. Various examples of co-processing or pre-processing stages are also provided, including acid, base, AFEX, ammonia and other stages to enhance a desired effect.

Abstract: A system for achieving bubble stability within a cavitation chamber is provided. The system includes an impeller assembly, the impeller assembly having at least one impeller blade located within the cavitation chamber. The impeller assembly is magnetically coupled to an external drive system which is used to rotate the impeller, thereby causing bubbles within the cavitation chamber to move toward the impeller's axis of rotation. As a consequence, the bubbles become more stable. Preferably the axis of rotation of the impeller is positioned in a substantially horizontal plane, thus allowing the rotating impeller to counteract the tendency of the bubbles to drift upward and to accumulate on the upper, inner surfaces of the cavitation chamber. The impeller can be rotated continuously throughout the cavitation process or stopped prior to, or during, bubble cavitation.

Abstract: A method and apparatus for regulating the temperature of the cavitation medium for a cavitation chamber is provided. The cavitation medium is pumped through the cavitation chamber through a pair of chamber inlets and an external conduit connecting the two inlets. An external heat exchanger is used to regulate the cavitation medium temperature, the heat exchanger being either directly or indirectly coupled to the conduit. The cavitation medium can be circulated through the heat exchanger during chamber operation or, once the desired cavitation medium temperature is achieved, operation of the circulation system can be suspended. The heat exchanger can be used to lower the temperature of the cavitation medium to a temperature less than the ambient temperature; to withdraw excess heat from the cavitation medium; or to heat the cavitation medium to the desired operating temperature.

Abstract: A cavitation system in which a source gas, e.g., a reactant, is loaded into the cavitation medium prior to cavitation is provided. The cavitation system includes a cavitation chamber with suitable cavitation drivers and a cavitation medium reservoir, the chamber and reservoir being flexibly coupled together via a pair of conduits. The conduits can be fabricated from a plastic or, as is preferred for higher temperature liquids, a metal. Typically metal conduits are formed into a coil, thus providing the desired flexibility. Flexibility is required in order to allow the relative positions of the cavitation chamber and the cavitation medium reservoir to be varied.

Abstract: A system and method for degassing a cavitation fluid is provided. The cavitation system of the invention includes a cavitation chamber with one or more cavitation drivers and a degassing system coupled to the chamber. One or more heaters, such as resistive heaters, are coupled to an external surface of the cavitation chamber such that heat from the heaters is transmitted through the wall of the cavitation chamber and into localized regions of the cavitation fluid contained within the cavitation chamber. The heater or heaters increase the temperature of the localized regions of the cavitation fluid to a temperature above the boiling temperature of the cavitation fluid, thereby creating vapor bubbles which capture gas trapped within the cavitation fluid through a rectified diffusion process. A cavitation fluid cooler can be used to insure that the average temperature of the cavitation fluid is below that of the boiling temperature.

Abstract: Systems and methods for treating small elongated fibrous and particles of certain materials, e.g., PTFE materials in a suspension are presented. In some instances, high-intensity ultrasound (or acoustical energy) is applied to a sample of the material, through a fluid coupling medium or suspension, to achieve a material transformation in the sample. In various embodiments, fibrillation of particles of PTFE or similar materials is accomplished, or the formation of extended structures of these materials is caused or enhanced. Also, the ability to separate long fiber samples by ultrasonic or acoustic cavitation action is provided.

Abstract: Methods and systems for electrodeposition of Indium, Gallium, or other metals within a metal acoustic resonator chamber are provided, including for electrodeposition of Indium or Gallium as a strike layer on an interior surface of a cavitation chamber. The resultant strike layer affords an accommodating wetting surface for subsequent filling with a liquid metal and performing cavitation therein. In some embodiments, this allows for the use of liquid metal in an acoustic resonator without the damping effects inherent with oxide boundaries or other defects.

Abstract: A system for achieving bubble stability within a cavitation chamber is provided. The system includes an impeller assembly, the impeller assembly having at least one impeller located within the cavitation chamber. A motor, coupled to the impeller by a drive shaft, rotates the impeller thereby causing bubbles within the cavitation chamber to move toward the impeller's axis of rotation. As a consequence, the bubbles become more stable. Preferably the axis of rotation of the impeller is positioned in a substantially horizontal plane, thus allowing the rotating impeller to counteract the tendency of the bubbles to drift upward and to accumulate on the upper, inner surfaces of the cavitation chamber. The impeller can be rotated continuously throughout the cavitation process or stopped prior to cavitating the bubbles within the cavitation chamber.

Abstract: A method of fabricating a spherical cavitation. Depending upon the chamber's composition and wall thickness, chambers fabricated with the disclosed techniques can be used with either low or high pressure systems. During chamber fabrication, initially two spherical half portions are fabricated and then the two half portions are joined together to form the desired cavitation chamber. During the fabrication of each chamber half, the interior spherical surface is completed first and then the outer spherical surface. Prior to joining the two spherical cavitation chamber halves, the surfaces to be mated are finished, preferably to a surface flatness of at least 0.01 inches. Electron beam welding is used to join the chamber halves together. Preferably the electron beam welding operation is performed under vacuum conditions. During electron beam welding, the two chamber halves are aligned and held together while the electron beam forms a weld along the chamber seam.

Abstract: A method for forming and imploding cavities within a cavitation chamber is provided. A hydraulically actuated piston is withdrawn to form the desired cavities and then extended to implode the cavities. The cavitation fluid is degassed prior to hydraulically driving cavitation within the chamber. Degassing can be performed within the cavitation chamber or within a separate degassing chamber. In one aspect, a coupling sleeve is interposed between the hydraulic driver and the cavitation chamber. Preferably the coupling sleeve is evacuated.

Abstract: A cavitation chamber separated into three volumes by a pair of gas-tight and liquid-tight seals, each seal formed by the combination of a rigid acoustic reflector and a flexible member, is provided. During chamber operation, only one of the three volumes contains cavitation fluid, the other two chamber volumes remaining devoid of cavitation fluid. The cavitation system also includes a cavitation fluid reservoir coupled to the cavitation chamber by a conduit, a valve allowing the cavitation chamber to be isolated from the cavitation fluid reservoir. A second conduit couples the two unfilled chamber volumes to a region above the liquid free surface within the cavitation fluid reservoir. A second valve allows the two unfilled chamber volumes to either be coupled to the cavitation fluid reservoir by the second conduit, or be coupled to a third conduit, the third conduit leading either to the ambient atmosphere or to a high pressure gas source. The cavitation system also includes at least one acoustic driver.

Abstract: A cavitation system for forming and imploding cavities within a cavitation chamber is provided. The system includes a hydraulically actuated driver coupled to the cavitation chamber. A cavitation piston, coupled to a hydraulic piston, forms the desired cavities during piston retraction and then implodes the cavities during piston extension. Preferably the cavitation fluid is degassed prior to hydraulically driving cavitation within the chamber. Degassing can be performed within the cavitation chamber or within a separate degassing chamber which is preferably connected to the cavitation chamber. In one aspect, a coupling sleeve is interposed between the hydraulic driver and the cavitation chamber, the coupling sleeve housing at least a portion of the cavitation piston drive rod. Preferably the coupling sleeve can be evacuated. In another aspect, a cavitation fluid circulatory system is coupled to the cavitation chamber.

Abstract: A method and apparatus for monitoring a temperature difference between two regions within a cavitation system is provided. The system's cavitation chamber is partially or completely filled with cavitation fluid, the amount that the system is filled controlling whether a cavitation fluid free surface is formed within the cavitation chamber or a conduit coupled to the chamber. Regardless of whether the region of the system above the cavitation fluid free surface is within the chamber or within the conduit, a temperature difference is created between this region and the cavitation fluid within the cavitation chamber. The temperature difference between these two regions is monitored by monitoring the temperature of each region. The temperature difference can be created by either heating the region above the cavitation fluid free surface, cooling the cavitation fluid, or both.

Abstract: A cavitation system for forming and imploding cavities within a cavitation chamber is provided. The system includes a hydraulically actuated driver coupled to the cavitation chamber. A cavitation piston, coupled to a hydraulic piston, forms the desired cavities during piston retraction and then implodes the cavities during piston extension. Preferably the cavitation fluid is degassed prior to hydraulically driving cavitation within the chamber. Degassing can be performed within the cavitation chamber or within a separate degassing chamber which is preferably connected to the cavitation chamber. In one aspect, a coupling sleeve is interposed between the hydraulic driver and the cavitation chamber, the coupling sleeve housing at least a portion of the cavitation piston drive rod. Preferably the coupling sleeve can be evacuated. In another aspect, a cavitation fluid circulatory system is coupled to the cavitation chamber.