Free piston pulse tube engine: a numerical and experimental power generation estimation

Abstract

Abstract The results of theoretical and experimental study of the atmospheric pulse tube engine (PTE), which is a kind of thermal inertial Stirling engine, are presented. The main advantage of the PTE is the absence of the moving design elements in heated part make it a perspective technology for waste heat recovery. Firstly, numerical simulation was conducted to design the system and optimum structure parameters of the system were obtained as well as the values of the free-piston PTE resonant frequency, the levels of the input and rejected heat, and the net power. Comparison of the net power and the thermal efficiency of the pulse tube engine with the crank mechanism and the free piston is provided. A comparison of operating conditions and engine start conditions for different free piston masses and temperatures in the hot heat exchanger is performed. The results are compared to prior numerical studies. The maximum value of the net power of the PTE was achieved for the frequency of 11.8 Hz, the input thermal power of 160 W and the temperature of 640 K.