Research on the Cooling Fan Speed Control Scheme of the Large Power Vehicular Diesel Engine in Altitude Environment

The cooling water of the large power vehicular diesel engine often got high or low and engine could not work in the adaptive thermal conditions in altitude environment. In order to solve the problem, analyzed the refrigeration requirement of the diesel engine on plateau section, suggested the amelioration program from installing the fluid operated pump-mot fan speed regulating device. Base on the coupling simulation model of the diesel engine working process and coolant system, took the 90°C water temperature of the diesel engine as the optimally target value, analyzed the change canon of cooling fan speed form the ambient conditions and the diesel engine work condition, established the cooling fan rotary speed control MAP on plateau section, and regulated the cooling fan speed by the methods of open loop preset controlling and closed loop feedback controlling. That would provide the improved method for the large power vehicular diesel engine working well on plateau section.