Performance characteristics of a Gamma type Stirling engine using Fresnel lens

ABSTRACT In this study, a gamma type Stirling engine was tested for its performance using a solar radiation concentrator. The displacer cylinder of the engine was constructed so that the cylinder head can be detached from the engine body. The engine’s performance tests were conducted for three different materials i.e. cast iron, aluminium and brass. The displacer cylinder head was made up of these three materials separately and was fitted to the displacer cylinder of the engine and tested. Of the three displacer cylinder materials, aluminium provided the best performance and followed by brass and cast iron respectively. 72.5 W was the maximum shaft power observed on conducting the test with the displacer cylinder made up of aluminium. 345 rpm engine speed and 2.01 Nm torque were the corresponding values for the maximum shaft power obtained using aluminium as displacer cylinder material. Fresnel lens of capture area 1.6 m2 was used for concentration of solar radiation on the displacer cylinder. Keywords: Stirling engine, speed, torque, power