A thermoacoustic transducer apparatus is disclosed including at least one thermal converter operable to provide power conversion between acoustic power and thermal power in a pressurized working gas contained within a working volume, a portion of which extends through the thermal converter. The thermoacoustic transducer is operable to cause a periodic flow in the working gas during operation. The apparatus also includes a reservoir volume in fluid communication with the working volume through a conduit having a working volume end in fluid communication with the working volume and a reservoir volume end in fluid communication with the reservoir volume. The conduit has a bore size and length operable to cause pressure oscillations at the working volume end to be converted to flow oscillations at the reservoir volume end such that periodic fluid flow at the reservoir volume end is at least twice as large as periodic fluid flow at the working volume end thereby facilitating a steady fluid flow along the conduit for equalization of working gas static pressures between the working volume and the reservoir volume while providing a sufficiently high acoustic impedance at the working volume end to minimize losses due to periodic flows of working gas within the conduit.

A thermoacoustic device includes a loop pipe, a first stack that is disposed in the loop pipe and that generates a sound wave in the loop pipe by way of a temperature gradient, a second stack that is disposed in the loop pipe and that generates a temperature gradient, a first high temperature side heat exchanger that is disposed at one end of the first stack and that makes the temperature of the one end of the first stack be higher than the other end, and a first low temperature side heat exchanger that is disposed at the other end of the first stack and that makes the temperature of the other end of the first stack be lower than the one end.

According to an aspect of some embodiments of the present invention there is provided a method for converting energy. The method comprises receiving energy from an external source, using the received energy for inducing a mass exchange process to release thermodynamic energy, and converting the thermodynamic energy directly into electrical energy at sufficient amount for performing work therewith. In some embodiments of the present invention, a portion of the released energy is converted to a pressure wave, and the mechanical energy constituted by the pressure wave is converted to non-mechanical energy.

A thermoacoustic device includes a stage coupled to a bar, wherein the stage includes a first heating component on a first terminus of the stage. The stage further includes a first cooling component on a second terminus of the stage. A thermal conductivity of the stage is higher than a thermal conductivity of the bar. A heat capacity of the stage is higher than a heat capacity of the bar.

An apparatus for performing energy transformation between thermal energy and acoustic energy is in a thermoacoustic transducer apparatus is disclosed. The acoustic energy is associated with a periodic flow of a working fluid within an acoustic power loop of the thermoacoustic transducer. The apparatus includes a common central plenum having a first fluid port for providing fluid communication with the acoustic power loop, and a plurality of discrete cylindrical thermal converters radially arranged about the plenum, each thermal converter including a regenerator. The apparatus also includes a second fluid port for providing fluid communication between the thermal converter and the acoustic power loop, and fluid flow passages in fluid communication with the plenum and extending through the regenerator to the second fluid port.

A thermoacoustic device includes a loop pipe, a first stack that is disposed in the loop pipe and that generates a sound wave in the loop pipe by way of a temperature gradient, a second stack that is disposed in the loop pipe and that generates a temperature gradient, a first high temperature side heat exchanger that is disposed at one end of the first stack and that makes the temperature of the one end of the first stack be higher than the other end, and a first low temperature side heat exchanger that is disposed at the other end of the first stack and that makes the temperature of the other end of the first stack be lower than the one end.

An energy conversion device includes a first acoustic wave generator, a second acoustic wave generator, and an output unit which are provided in a pipe member. The first acoustic wave generator has a thermal energy generator configured to generate thermal energy from electric energy, and converts the thermal energy generated by the thermal energy generator into acoustic energy to generate acoustic wave in working gas by a self-excited thermo acoustic vibration. The second acoustic wave generator converts thermal energy supplied from a heat supply source into acoustic energy and generates acoustic wave in working gas by a self-excited thermo acoustic vibration. The output unit converts the acoustic energy of the acoustic waves from the first acoustic wave generator and the second acoustic wave generator into cold energy to output.

A Stirling engine feedback controller is provided that includes a Stirling engine having at least one piston, where the Stirling engine includes an Alpha-Stirling engine, and a Gamma-Stirling engine. The feedback controller includes a power sensor, a computer, and an electronic feedback loop. Here, the power sensor is configured to sense the power of the Stirling engine then output a power signal. In one aspect, the computer can be a central processing unit (CPU), or a field programmable gate array (FPGA), where the computer operates a control algorithm. Further, the electronic feedback loop receives the output power signal and an output signal from the computer, where an output signal from the electronic feedback loop is configured to a control a position of the piston(s).

A thermo-acoustic engine and/or cooler is provided and includes an elongated tubular body, multiple regenerators disposed within the body, multiple heat exchangers disposed within the body, where at least one heat exchanger is disposed adjacent to each of the multiple regenerators, multiple transducers axially disposed at each end of the body, and an acoustic wave source generating acoustic waves. At least one of the acoustic waves is amplified by one of the regenerators and at least another acoustic wave is amplified by a second one of regenerators.

A thermoacoustic device includes a process volume which is filled with a working fluid through which the acoustic wave propagates. The thermoacoustic device further includes an acoustic network comprising a tubular loop configured with a passage providing an opening in the loop and configured as acoustic circuit provided with a compliance volume, a thermo-acoustic core and an inertance volume. Within the loop, the thermoacoustic core is at a first side thereof adjacent to the passage at a first path length through the loop, and at its second side, opposite to the first side, the thermoacoustic core is at a second path length from the passage. The thermoacoustic device includes within the loop a spring-type partitioning element that is configured to close off the cross-section of the tube and to be impermeable for the working fluid while allowing transmission of pressure waves in the working fluid through the spring-type partitioning element.