Study Of Aero-engine Nacelle Flow And Heat Transfer Calculations

Aircraft nacelle comprises engine, engine casing and accessories. The temperature inside the nacelle is greatly high because of heat transfer from engine, and the accessories may work out of order or even be damaged without reasonable structure or effective cooling, therefore, the temperatures of certain points should be under limited value in nacelle design criterion.In this paper, the calculational methods of air flow through the general aircraft nacelles are established according to the structure characteristic and bleeding-exhaust form. The calculation models of flow and heat transfer of helicopter nacelle are created; the flow and temperature fields are computed when helicopter nacelle is operating under ground maximum state, and the results indicate that the temperatures of monitoring points in rear-nacelle exceed the limited value, so the structure of nacelle should be improved to a certain extent.Two schemes are presented to improve nacelle structure. The flow and temperature fields are calculated respectively. The results show that the effects of flow and temperature fields have been improved in some extent compared with the original one; and the temperatures of monitoring points are less than the limited value. The schemes presented in this paper are effective on engineering application.