Investigation On Characteristics Of Standing Wave Thermoacoustically Driven Pulse Tube Refrigeration

A thermoacoustically driven pulse tube refrigerator occupies outstanding advantages of structure simplicity, reliability, heat-driven mechanism, environmental friendliness and so on. Due to no moving components from ambient to cryogenic temperatures, the novel technology of thermoacoustically driven pulse tube refrigeration has a bright prospect of application. In order to explore the couple relation of the acoustic pressure amplifier (APA), to investigate its characteristics and the refrigeration performance enhancement, the theoretical and experimental work of this thesis focuses on the following sections:1. Improvement on a Computer Module for Thermoacoustic Engine Driving an RC Load through APA on Thermoacoustics Work is done on an existing computer module for thermoacoustic engine driving an RC (resistance and compliance) load through APA by platform migration and modularization to make it more friendly and extendable, so as to promote the further research.2. Simulation on Thermoacoustic Engine Driving an RC Load through APA A standing wave thermoacoustic engine connected with an RC load through an APA has been numerically simulated with linear thermoacoustics. According to the computed results, the influences of length and diameter of APA and impedance of RC load on the performance have been analyzed. Further discussions on the amplifying effects of pressure ratio and acoustic power output by APA as well as the coupling relation of the thermoacoustic engine and the RC load through APA are given..3. Experimental Investigation on Characteristics of Thermoacoustically driven Two-stage Pulse Tube Refrigerator (PTR) through APA A two-stage double-inlet pulse tube refrigerator driven by a standing wave thermoacoustic engine through an APA has been tested. Influences of working pressure and heating power on performance of the PTR have been investigated. Under the conditions of 2.8 MPa working pressure, 2.0 kW heating power input, and with an APA of 3.4 m in length and 8 mm in diameter, pressure amplitude and pressure ratio at PTR inlet reached 0.223 MPa and 1.174, respectively, and a cooling temperature as low as 41.2 K at the second stage cold tip has been achieved.