抄録
Thermoacoustic cooler is one of promising device for utilization of unused thermal energy. The objective of this paper is to study thermoacoustic cooling utilizing an acoustic traveling-wave in the looped tube with a branch resonator. The numerical simulation and experiment were carried out for various thermoacoustic stacks composed of mesh screens whose size of aperture was different under constant porosity. Firstly, using finite-difference time-domain (FDTD) method, pressure, velocity and phase difference of sound wave were calculated for various stack structure. Since the calculated results were almost agree with the experimental results, the validity of analytical model was depicted. Also it was found that the traveling-wave component increases with increasing flow resistance of the stack defined by aperture size of the mesh. Secondly, heat-pumping process in the stack was numerically simulated taking account of heat exchange between the solid wall and the oscillating fluid. As the results, thermoacoustic cooling effect was clarified in relation to the thermal response of stack and the phase difference between pressure and velocity of the sound wave. The optimum size of aperture in the stack for thermoacoustic cooling was depicted experimentally and analytically.
