Investigation On Performance Enhancement Of A Standing-wave Thermoacoustic Engine

A thermoacoustically driven pluse tube refrigerator occupies outstanding advantages of simplicity, reliability, stability, longevity and so on, due to no moving parts from ambient to cryogenic temperatures. This new concept refrigerator attracts great interest of academic circles and industry.This paper presents a review of developments and applications of thermoacoustic engines. The linear thermoacoustics is introduced in detail. The importance and development of the non-linear thermoacoustics are briefly analyzed. The following programes are carried out:1) A program named DeltaE is introduced for numerical simulation on thermoacoustics.2) The pressure amplifier is defined. The effects of an ideal smooth pipe, a viscous pipe of one end closed and a viscous pipe of one end connected with load on amplifying pressure are analyzed, respectively. The experiments on a standing-wave thermoacoustic engine have validated that the optimum length of the pipe is far smaller than the calculated one, and related with the input power, working pressure, load and so on.3) The standing-wave thermoacoustic engine driven RC (Resistance and Capacitance) load with the pressure amplifier has been numerically and experimentally studied. The computation reveals that the acoustic power at the inlet of the load is maximum when the resistance is equal to capacitance (the phase difference between p₂ and p₃, is 45 Degree). The experimental results have demonstrated that the pressure amplifier not only amplifies the pressure ratio, but also improves the acoustic power. The efficiency of the machine with a length of 3.45m pressure amplifier rises from 1.45% to 3.32% .4) The standing-wave thermoacoustic engine driven pulse tube refrigerator with the pressure amplifier has been experimentally studied. A cooling temperature as low as 79.1K with a working pressure of 2.465MPa has been obtained which is about 10K lower than that without the pressure amplifier.5) We designed and produced a finned cooler according to the TASFE (Time-Average...