Performance comparison of a novel configuration of beta-type Stirling engines with rhombic drive engine

•The paper describes a novel arrangement of a beta-type Stirling engine.•Its performance was compared with rhombic drive engine.•The power output of the engine was found to be greater than rhombic drive.•Efficiency was found to be higher than rhombic drive at the same working fluid mass.•Efficiency was found to be lower than rhombic drive at the same charge pressure.

This study presents a beta type Stirling engine mechanism and its performance analysis. The displacer motion of the engine is performed by a lever mechanism. The performance of the engine was investigated via comparing with a rhombic-drive engine possessing an equal sided rhombic. Comparison was made for kinematic behaviors, power and thermal efficiency. For comparison; the piston swept volume, the inner heat transfer area, the hot and cold end temperatures, the inner heat transfer coefficient, charge pressure and dead volumes were kept equal for both engines. As working fluid the helium was used. Thermodynamic treatments of engines were performed via the nodal analysis. The power of the lever driven engine was found to be greater than the power of the rhombic drive engine. Under the equal charge pressure, the thermal efficiency of the lever driven engine was found to be lower than the efficiency of the rhombic drive engine however, under the equal working fluid mass the thermal efficiency of the lever driven engine was found to be greater than that of the rhombic drive engine. The external volume and mass of the lever driven engine is lower than the rhombic drive engine.