Konceptstudie av Waste Heat Recovery System på Tunga Fordon
In today?s fast growing and closely connected society, a reliable and energy efficient transportation system is more than ever desirable. Nowadays the significant part of the transportation sector?s energy demand is supplied by fossil fuels.Improving energy efficiency in combustion engines will result in reduction of fuel consumption and CO2 emissions. A modern internal combustion engine has an efficiency of 30-45 %, where the most energy loss occurs as result of heat losses in the exhaust and cooling systems. By recovering and converting the thermal energy of a combustion engine to mechanical/electric power the efficiency of the combustion engine can be increased.In this work the performance of a truck engine has been investigated with the aim to increase its efficiency by decreasing the heat losses with a Waste Heat Recovery (WHR) system. Intercooler, coolant system, EGR and exhaust systems have been studied for their heat loss potentials.A model of an ideal Rankine process has been implemented in MATLAB with water as the working fluid. Experimental data sets from a Scania DC1306 and a Volvo D11 engines have served as inputs to the developed MATLAB model. The study shows that an efficiency gain of approximately 2 % can be achieved with a WHR-system where EGR cooler serves as a heat source and 2.5 % with the exhaust as heat source. The combination of both systems can provide an efficiency gain between 4-5 %.