Influence of Dead Space Ratio for the Efficient Working of an Alpha Type Stirling Engine – Mathematical Analysis

Abstract

An Alpha type Stirling engine is different from the other two types in a way that it has two power pistons; one in hot cylinder while other in the cold one. Based on expansion and compression in both cylinders, the engine cyclically operates by external heat source. The efficiency of the engine is recognised by its work done which relies on a number of factors including phase angle, swept volume and dead space. This research demonstrates the efficient working of an Alpha type Stirling engine through optimising the three parameters with a specific focus on the dead  space ratio of two cylinders using Schmidt analysis. The analysis of impact of other parameters to counter the effect of dead space is also the part of examination. The results reveal that negative effects of dead space could be neutralized through suitable selection of other variable parameters. The appropriate combination of swept volumes of both cylinders helps in minimising the effects of dead space and assists in attaining the desired efficiency. The optimal selection of phase angle is also vital, though a little complexed. The results are presented graphically. The analysis reveals that negative effects of one parameter could be countered through appropriate selection of other parameters to attain the desired efficiency. The findings are applicable at bench, pilot and industrial scales.