Investigation on the Impact of Displacer Equivalent Mechanical Damping Coefficient on the Performance of a Free-piston Stirling Generator [排出器等效机械阻尼对斯特林发电机性能影响分析]

作者：Jiang Z.-J.; Zhu S.-M.; Yu G.-Y.^*; Dai W.; Luo E.-C.

来源：Journal of Engineering Thermophysics, 2022, 43(4): 857-862.

• Displacer
• Equivalent mechanical damping coefficient
• Free-piston stirling engine (FPSE)
• Thermoacoustic

Free-piston Stirling electric generator is an efficient and compact external combustion heat engine, which has significant application prospects in energy-saving applications such as distributed CHP (combined heat and power). Based on a self-manufactured free-piston Stirling generator, this paper studies the influence of the displacer equivalent damping coefficient Rm on the performance of the generator, and compares it with the experimental results. Results indicate that the change of Rm will first affect the internal acoustic field, leading to changes in the acoustic impedance of the interface between engine and alternator, which consequently inflicts mismatch. Then, Rm directly changes the dynamic loss and exergy loss of the displacer and induces the loss of the piston. In the calculation, when Rm increases from 0.5 Ns/m to 80 Ns/m, the electrical power decreases from 5247 W to 4673 W, i.e., 12.2% of reduction, meanwhile the electrical efficiency decreases from 40.4% to 36%. In the experiment, when Rm is 30 Ns/m, the electrical power is 4307 W, the electrical efficiency is 33%, corresponding to a discrepancy of 13%.

• 出版日期2022
• 单位中国科学院大学