A zero-c.o.p. thermoacoustic refrigerator has been fabricated and investigated experimentally to verify the thermoacoustic refrigeration effect and to test the performance. Without any heat exchangers at both ends of stack(and thus with zero c.o.p.), temperatures on the stack are measured and various heat transfer rates are calculated from the temperatures.
The equations of heat and work flow rates through total cross section of the square-pore stack have been theoretically derived. Temperatures on the stack have been calculated numerically using them. Measured temperatures are in agreement with calculated temperatures for lower frequency than 300Hz, but the former deviates from the latter considerably for higher frequency.
Two types of COP($η_1$·$η_2$) have been defined as are appropriate to the experiment. When $η_2$ is zero(the condition in which pumped heat flow rate in the pore exactly cancels the axial heat conduction down the stack), the obtained $η_1$ is found to be about 0.14 for 300Hz from the experiments.
