| Thermoacoustic prime mover is an absolutely new type of compressor. Without any moving part, it occupies many advantages over the traditional mechanical compressors, such as simplicity, reliability, and vibration free for long non-maintenance operation. A pulse tube refrigerator driven by a thermoacoustic compressor, instead of a mechanical one, is expected to be a promising long-term-operation cryocooler, and it is even possible to replace the traditional cryocoolers, such as Stirling cycle refrigerator, in some applications.After a detailed review on the historical developments of the research on thermoacoustics, as well as the latest advances in this field, prospective applications, and a survey of theoretical fundamentals, the present work focuses on the following sections:1) Standing Wave Thermoacoustic Prime Mover An experimental setup of standing wave thermoacoustic prime mover has been built up with brass matrix as the thermoacoustic stack. It is a symmetrically heated system, achieving pressure ratios of 1.10 and 1.06 with nitrogen and helium as the working fluids, respectively. Experimental investigation has been made on the influence of the operating parameters, structure parameters, and working fluids on the performance of the system. Some latest improvements have been made on the heating system and the cold end heat exchanger to strengthen the system for safer operation.2) Hysteretic Loop Emphasis has also been focused on the onset and damping behavior of the thermoacoustic oscillation. Based on the acute review and analysis on the non-steady processes with hysteresis, a hysteretic loop is proposed and experimentally verified for the first time in the standing wave thermoacoustic prime mover. Hysteresis is not only found for the temperatures, due to the difference between the onset and damping temperatures, but also for the input heating power, i.e., the critical onset power is also different with the critical power for the damping process. A mixed-powered thermoacoustic prime mover concept is also presented in use of hysteresis, which may be helpful for the application of low-qualified energy to thermoacoustic machines.3) Traveling-Wave Thermoacoustic Prime Mover Also known as thermoacoustic Stirling engine, traveling-wave thermoacoustic prime mover is a newly proposed thermoacoustic system. Anexperimental setup has been designed and built up through a collaboration program between Cryogenics Laboratory in Zhejiang University and LIMSI-CNRS (France). The system employs the inherently reversible Stirling cycle, and then its thermodynamic efficiency can easily surpass that of standing-wave system and is even comparable to that of the traditional internal combustion engines. Recent experiments have succeeded in obtaining oscillations from the new system, with frequencies of 66Hz and 23Hz for the cases with helium and nitrogen as the working fluids, respectively. The traveling wave system is expected to be one of the good candidates as a driver for pulse tube refrigerator, leading to a thermoacoustically driven pulse tube refrigerator without any moving component. Some simulations with DeltaE has also been made to predict the performance of the system. At the end of this section, proposals and schemes are also given for the further experiments.4) ThermoAcoustically Driven Puke Tube Refrigerator(TADPTR) With the successful operation of the standing wave thermoacoustic prime mover, we transferred part of our efforts to the thermoacoustically driven pulse tube refrigeration, which is actually the original aim for our study on the thermoacoustic prime mover. First of all, we discussed the matching problems between a thermoacoustic prime mover and a pulse tube refrigerator, which is very important due to the remarkable differences between the operating characteristics of the two separate parts, such as operating frequency, pressure ratio, and phasing. An experimental apparatus has been constructed with the exist prime mover and a single-stage co-axial type...
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