The effects of altitude on the heat transfer performance of the radiator in diesel engine were investigated based on the environmental characteristics of the flight height and high elevation plateau. The flow and heat transfer models of the thermal management system (TMS) of diesel engine were then established to investigate the effects of altitude on the TMS. Furthermore

the method for matching the operating parameters of the TMS under different working conditions was given based on the principle of minimum power consumption. The results under prescribed heat load conditions show that

at flight height

the heat transfer performance of the radiator increases first and then decreases with the increasing altitude

and the temperatures of the coolant and oil in the TMS decrease first and then increase whilst the minimum power consumption of the TMS decreases first and then increases. In the elevated plateau area

the heat transfer performance decreases with the increasing plateau altitude

and the temperatures of the coolant and oil in the TMS increase significantly

causing the engine overheating. The minimum power consumption of the TMS increases remarkably with the increasing plateau altitude in order to provide enough heat dissipation ability for the engine.