A zero-dimensional model for simulation of a Diesel engine and exergoeconomic analysis of waste heat recovery from its exhaust and coolant employing a high-temperature Kalina cycle

Abstract

An exergoeconomic assessment is performed for a high-temperature Kalina cycle which is proposed to produce power from a Diesel engine exhaust and coolant. Developed zero-dimensional model for the engine simulation revealed its parameters as well as the influences on the thermodynamic and exergoeconomic parameters of the waste heat recovery system of the engine speed. Moreover, the system responses to the changes of the Kalina important parameters are assessed. Examining the locations of pinch point temperature differences in the system heat exchanging devices showed a proper thermal matching because of using a zeotropic working fluid. Results showed that the proposed cycle could produce 21.74 kW power from the waste heat recovery process, which is significant for a 98.9 kW engine. Energy and exergy efficiencies are also calculated to be 25.55% and 55.52%, respectively, and unit cost of the produced power in the Kalina turbine is measured as 15.52 cent/kWh, for a specific considered condition. The parametric study revealed a rise in the system produced power with the engine speed. Moreover, it is found that the produced power unit cost, as well as the system total cost, is reduced with increasing the turbine inlet temperature and pressure.