experimental investigation on the effect of egr mixture temperature on the second law efficiency in light-duty diesel engines

current approaches to the analysis of internal combustion engines are no longer merely based on the first law of thermodynamics and are conducted from the second law either. the evaluation of processes by the first law cannot provide a sophisticated insight into the issue. so, due to the necessity of having a detailed perspective of the losses in different thermodynamic processes, a useful method called the exergy analysis in required. the amount of emissions produced by diesel engines, especially soot and nox, are higher in comparison with spark ignition engines. one of the common methods to suppress nox emission is the recirculation of exhaust gas to the cylinder. this method causes the in-cylinder peak temperature reduction so that the less amount of nox would be formed. in the following study, the effect of recirculated exhaust temperature and ratio on the exergy destruction of a diesel engine is investigated. the results revealed that by increasing the mass ratio and temperature of the air-exhaust mixture, the second law efficiency generally decreases in various loads and engine speeds.