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The present investigation deals with the analysis of the performance of twin thermoacoustic prime mover (TAPM) which are measured in terms of frequency and pressure amplitude by varying the parameters such as temperature gradient along the length of stack and the operating pressures of fluid medium argon using CFD simulation. With the help of CFD researchers and Engineers can evaluate the performance of a wide range of thermoacoustic systems on the computer without the time, expense, and disruption required to make actual changes onsite (stack) which is tedious to fabricate.

For the present simulation, the operating pressures of argon such as 1bar, 3bar and 5bar, and the temperature gradient is varied from 600K to 1400K with the regular intervals of each 200K. The geometry of twin TAPM is created using GAMBIT processor, and the simulation is carried out using FLUENT. The geometrical parameters of twin TAPM are kept constant throughout the simulation. The results for frequency and pressure amplitude obtained from the CFD simulation of twin TAPM for various temperature gradient and operating pressures are analysed and reported.

The computational results of twin thermoacoustic prime mover shows an increase in pressure amplitude with an increase in the temperature gradient and also it increases with an increase in operating pressures of the fluid medium. The parameter operating pressures of the working fluid medium and the stack hot end temperature has no significant effect on the output, frequency.

Though several experimental works had been published based on the twin thermoacoustic prime mover, an attempt has been made in the present investigation for the first time to estimate the performance of twin thermoacoustic prime mover using CFD package (ANSYS-FLUENT) by varying temperature gradient. The temperature gradient and operating pressures were varied and the performance of twin thermoacoustic prime mover was measured in terms of frequency and pressure amplitude.

The purpose of this study is to achieve lower and lower temperature as infrared sensors works faster and better used for space application. For getting good quality images from space, the infrared sensors are need to keep in cryogenic temperature. Cooling to cryogenic temperatures is necessary for space-borne sensors used for space applications. Infrared sensors work faster or better at lower temperatures. It is the need for time to achieve lower and lower temperatures.

This study presents the investigation of the critical Stirling cryocooler parameters that influence the cold end temperature. In the paper, the design approach, the dimensions gained through thermal analysis, experimental procedure and testing results are discussed.

The effect of parameters such as multilayer insulation, helium gas charging pressure, compressor input voltage and cooling load was investigated. The performance of gold-plated and aluminized multilayer insulation is checked. The tests were done with multilayer insulation covering inside and outside the Perspex cover.

By using aluminized multilayer insulation inside and outside the Perspex cover, the improvement of 16 K in cool-down temperature was achieved. The cryocooler is charged with helium gas. The pressure varies between 14 and 18 bar. The optimum cooling is obtained for 17 bar gas pressure. The piston stroke increased as the compressor voltage increased, resulting in total helium gas compression. The optimum cool-down temperature was attained at 85 V.

The cryocooler is designed to achieve the cool-down temperature of 2 W cooling load at 100 K. The lowest cool-down temperature recorded was 105 K at a 2 W cooling load. Multilayer insulation is the major item that keeps the thermal radiation from the sun from reaching the copper tip.