Simulation on the ventilation cooling performance of the helicopter engine nacelle in forward flight

A simplified method of evaluating the ventilation cooling performance of the engine nacelle based on rotor downwash flow was presented, for the engine nacelle ventilation cooling system of the helicopter. Using the business CFD software, the flow field and the temperature field in the nacelle in forward flight were calculated for single-inlet scheme and double-inlets scheme, total up to 9 schemes. The influence on the cooling performance was analyzed for different inlet number, inlet size and inlet position. And the comparisons were completed between flight test and numerical simulation results. The results show that the method can exactly forecast the performance of the ventilation cooling system of the helicopter nacelle, and the simulated results can be regarded as reference for the design and optimization of the system.