Influence of acoustic pressure amplifier tube on a 300 Hz thermoacoustically driven pulse tube cooler

High frequency thermoacoustically driven pulse tube coolers (PTCs) have the advantages of high energy density, compact structure, and high reliability. Through a series of improvements, the 300 Hz thermoacoustically driven PTC in this paper achieved a fourfold increase in the cooling power compared with that in our last report. A cooling power of 1.04 W at 80 K and a no-load temperature of 63 K are obtained with 500 W heating power. In the system, the acoustic pressure amplifier tube (APAT) plays an important role in coupling the thermoacoustic engine and the PTC. The effects of APAT on the system performance are investigated here through both numeric simulations and experiments. The simulation indicates that length of the APAT is limited due to impedance match requirement between the PTC and the engine, which is partly evidenced by experiments. Calculation also gives a good agreement between calculated pressure wave amplification ratio and experimental values. APAT with different lengths and diameters are investigated through experiments which indicate that there is an optimum diameter for the system performance. (C) 2010 American Institute of Physics. [doi:10.1063/1.3484046]