The prediction of combustion behavior and pollutant species by changing intake valve closure time

Abstract

Using the finite‐volume method, the relations between different cam shafts profiles have been derived while the intake valve opening time and maximum lift are equal and the engine is equipped with a turbo charger. For this purpose, all equations are solved in one dimensional GT POWER and three‐dimensional AVL FIRE software. The results, such as engine performance and in‐cylinder pressure and temperature are presented. They show that with earlier intake valve closure, it is possible to decrease maximum in‐cylinder pressure as well as maximum temperature, while engine output variation is negligible. Concerning emission species, NOx—as one of the most important emissions in gas engines—is almost reduced by half by reduction in intake valve opening time, although the amount of both unburned hydrocarbon and carbon monoxide shows an increasing trend. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 786–793, 2016