Design of dual flywheels with connecting rods for gamma-type Stirling engine

A gamma-type Stirling engine, based on a dual flywheels’ concept, was designed and fabricated. Optimized design of the engine, with connecting rods, was introduced to achieve a steady state of the Stirling engine cycle. Performances of the engine were therefore presented in terms of piston motion, inertia force, angular speed, pressure-volume diagram and temperature difference. It was found that optimum length of 45 mm from the connecting rod was able to reach the maximum output mechanical speed of 738 rpm at the maximum inertia force of 0.5 N. The engine offered thermal efficiency of 46.15% and total output power of 1.21 W under the temperature difference of 267 K. In the future, this design is expected to prove useful for applications in portable generators.