A thermoacoustic device includes a waveguide with a loop shape, a heat exchanger, and a thermally conductive member. The waveguide with a loop shape is filled with a medium. The heat exchanger is provided in the waveguide and has a lower temperature part and a higher temperature part that produce a temperature gradient therebetween. The thermally conductive member changes a temperature of a central part of at least one of the lower temperature part and the higher temperature part.

Disclosed are a thermoacoustic engine with high conversion efficiency from heat energy to acoustic energy and a designing method for the thermoacoustic engine. A stack of the thermoacoustic engine has a plurality of flow passages extending through a thermoacoustic piping section. A hot heat exchanger is coupled to one end in a longitudinal direction of the stack. A cold heat exchanger is coupled to the other end in the longitudinal direction of the stack. And a length in the longitudinal direction of the hot heat exchanger is greater than a length in the longitudinal direction of the stack, and is greater than a length in the longitudinal direction of the cold heat exchanger.

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.

An energy collecting device is disclosed. For example, the energy collecting device comprises a plate layer having a plurality of perforations for receiving a plurality of molecules, a molecular energy collecting layer, coupled to the plate layer, having an impacting structure for receiving the plurality of molecules, and a substrate layer, coupled to the molecular energy collecting layer, having a conductor wire coil for collecting electrons that are generated when the plurality of molecules impacts the impacting structure.

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.

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.

An energy collecting device is disclosed. For example, the energy collecting device comprises a plate layer having a plurality of perforations for receiving a plurality of molecules, a molecular energy collecting layer, coupled to the plate layer, having an impacting structure for receiving the plurality of molecules, and a substrate layer, coupled to the molecular energy collecting layer, having a conductor wire coil for collecting electrons that are generated when the plurality of molecules impacts the impacting structure.

The thermoacoustic energy converting element part includes a plurality of through holes extending along a uniform direction to penetrate a body of the thermoacoustic energy converting element part to form traveling paths of acoustic waves. The element part includes a wall surrounding each of the through holes to extend in an extending direction of the through hole and configured to exchange heat between the fluid. The through hole includes a through hole that has a hydraulic diameter of 0.4 mm or smaller, and an open area ratio of the through holes is 60% or higher. A first layer and a second layer are alternately provided on the wall of the thermoacoustic energy converting element part along the extending direction. A porosity of the first layer is 0% or smaller than a porosity of the second layer. The thermal conductivity of the structure of the thermoacoustic energy converting element part along the extending direction is 2 W/m/K or lower. If a metal plate is provided as the first layer, a plurality of the metal plates having a roughened main surface is layered and bonded by thermocompression bonding to manufacture the thermoacoustic energy converting element part.

A thermoacoustic electric generator system includes: a turbine including a turbine blade provided in an inside of a branched tube in a tube component and rotating by thermoacoustic oscillation of working gas in a thermoacoustic engine, and a turbine rotational shaft configured to be coupled to the turbine blade, penetrate a tube wall of the branched tube, and extend from the inside to an outside thereof; and a generator provided on the outside of the branched tube in the tube component, coupled to the turbine rotational shaft of the turbine, and converting rotational energy of the turbine blade to electric energy.

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.