Time Loss Analysis of an Unconventional Piston Engine

Piston motion affects the thermal efficiency of an internal combustion engine. The efficiency loss due to piston motion is defined as time loss, and accounts for 6 - 7 % of the total loss in a spark ignition engine. In this paper, an analysis is made of the time loss for a conventional slider-crank engine and a perfectly sinusoidal piston motion engine. The heat release rate is modeled using test data from an 1.6 / OHC engine, and parametric studies are made to identify factors affecting thermal efficiencies of engines with conventional and unconventional piston motions.