Cycle Simulation Of Stirling Cryocooler And Parametric Study Of Flexure Springs

Stirling refrigerator has been widely used in the aerospace and infrared detection, ifwe can play its high efficiency, long life advantages under the premise of reducingmanufacturing costs; it’s expected to explore its application in the field of general cold andheat pump, if researchers can deeply understand the heat flow process of the working fluid,use conventional materials and optimize the structure to reach the process requirements,it’s expected to substantially reduce the application threshold of Stirling refrigerator andpromote the Stirling technology into a mature stage. Under this background, the mainlyworks in this paper are in the following aspects:1. Establish control equations and adiabatic model without pressure drop, use Matlabto build simulation program, and do some researches on the general laws of the StirlingCryocooler work process: the temperature, the pressure, the mass, the system cycle powerof every components are in accordance with the sine law changes with the crank angle, thework done in the compressor is more than the expansion chamber, the hydrogen massaverage in the cold chamber is3.14times compared with the mass average in thecompressor, the hydrogen mass average in the heat exchanger is2.28times than the coldexchanger and is2.36times than the cooler. The variation of the interface temperaturebetween the room temperature cavity and the cold heat exchanger is related to the flowdirection of the hydrogen.2. By changing the load, the thickness and the groove width of the flexure springs,use FEM to do transverse and longitudinal comparative analysis. The results show that:increasing the thickness can get a greater coefficient than decreasing the groove width,with the elastic limit, the axial force, radial force is proportional to the axial displacement,the radial displacement; the axial stiffness is in a cubic relationship with the thickness, while the radial stiffness is in line change with the thickness. The natural frequency of theflexure spring can be obtained by modal analysis. Finally obtain the results: the circleinvolute flexure spring can provide a greater axial stiffness, radial stiffness and a highnatural frequency, it’s conducive to the reduction of weight of the whole system.3. The axial displacements obtained by experimental measure are smaller than theFEM results; the error is less than15%. Moreover, the resonance characteristics of thelinear motor, is studied by experiment. The analysis of experimental data shows that: withthe increase of the pneumatic pressure, the natural frequency of linear motor increases, thedynamic pressure wave of the piston surface still increases; the piston stroke is biggestwhen the resonance happens, and the phase difference between the current and the voltageis zero.