Light-Duty Diesel Advanced Thermal Management

摘要

In response to demands for improved fuel economy and current trends of rising heat rejection, increasing fan power, and reduced engine compartment package space, a light-duty diesel truck cooling system is replaced by an electric cooling system which features electric water pumps, an electric thermostat, electric fans, secondary cooling systems for the transmission and EGR, and a water-cooled charge air cooler with EGR added upstream of the CAC. The combination of these components improves the package space utilization and decreases the thickness of the heat exchanger module, resulting in improved underhood airflow. The temperature controllability is also significantly improved for the engine oil, engine coolant, intake manifold air, EGR, and engine block/valve seats. The improvements in cooling system efficiency are marked by a decrease in cooling system parasitic losses (fan and pump power) from 23.5 kW (base vehicle) to 3.6 kW, an 85% reduction.