Continue Internal Combustion Engines p Compression ratio,r MEP… r= max min min Mean effective pressure,MEP Vmav W MEP et net work for one cycle max min displacement volume Notes: o MEP would produce the same net work with constant pressure as for actual cycle (includes both expansion and compression) o want high MEP (high power density) 上游充通大 May9,2019 10 SHANGHAI JLAO TONG UNIVERSITYMay 9, 2019 10 Continue Internal Combustion Engines Compression ratio, r Mean effective pressure, MEP Notes: • MEP would produce the same net work with constant pressure as for actual cycle (includes both expansion and compression) • want high MEP (high power density) max BDC min TDC V V r V V   net max min W net work for one cycle MEP V V displacement volume    v p MEP Vmin Vmax