A new numerical thermodynamic model for a beta-type Stirling engine with a rhombic drive

This study presents a theoretical and numerical thermodynamic model for a beta -type Stirling engine with a rhombic-drive mechanism. This study focuses on developing a thermal model that overcomes the poor perfor-mance of previous models at high engine speed (above 60 Hz). The developed model is a modified version of the recently developed simple II model. The inaccuracy of the simple II model especially at high speed is improved by considering the power loss due to inertial forces and the variations of the gas temperature inside the heater and cooler with engine speed. The effect of several geometric and operational parameters. The accuracy of the developed numerical model is evaluated against experimental data of the GPU-3 Stirling engine. The difference between the current model predictions and experimental measurements for the output power and efficiency are 4.3% and 3.26% (as a difference), respectively. Moreover, the current model shows superior performance at high speed compared to previous models. It maintains its accuracy at high speed.