Optimal Stroke Path for Reciprocating Heat Engines

Figure 9

Sensitivity to compression ratio of reduction in frictional losses. Calculations are for unbounded acceleration. Ordinate is dynamic frictional losses for conventional piston motion relative to that for optimal piston motion, for internally dissipative friction. Abscissa is the compression ratio. The two curves are for different frictional exponents m and show the marked dependence on m.