Second-Law Analysis of Indirect Injection Turbocharged Diesel Engine Operation under Steady-State and Transient Conditions

A second-law analysis is performed in both chambers of an indirect injection turbocharged diesel engine and the simulation program developed is used to study the second-law performance of the engine at various operating conditions, steady state and transient. The simulation developed is based on the filling and emptying approach and provides detailed analysis of thermodynamic, dynamic and second-law differential equations on a degree crank angle basis. It incorporates a detailed mathematical simulation of the fuel pump and solves each equation separately for each one of the six cylinders of the engine in hand. The model is validated against experimental data at steady state and transient conditions, obtained at the authors' laboratory. The prechamber rate and cumulative availability terms and irreversibilities are computed and depicted against the main chamber ones during the 720 degrees crank angle of an engine cycle. Moreover, the effect of certain parameters on the second-law performance of the cylinder is studied, i.e. static injection timing, prechamber diameter and engine load. Explicit diagrams are given to show the response of the various cylinders' main chamber and prechamber availability terms during transient operation. Thus, the magnitude as well as the evolution of the various terms during a cycle or during a transient event is highlighted.