Numerical Simulation Method with Engine Power and Analysis of Jet Interaction

Abstract

To explore the effects of engine jet on overall aircraft aerodynamic performance, an aerodynamic numerical simulation method and the interference effects of aircraft with wing-mounted nacelle were studied. In aspect of numerical simulation, based on isentropic flow relationship and automatic mass-flow matching method, a high-precision / high-efficiency numerical simulation of inlet and exhaust boundary conditions is achieved. The calculation result is in good agreement with the experimental values, which validates the calculation method and boundary condition treatment. Through numerical simulation, it is found that the ejection of engine jet can accelerate the air flow, reduce the lower wing pressure, enhance the upper wing shock wave and increase the pitch down moment. At the same time, the effect of jet brings blowing drag and loses the cruise efficiency. The airflow acceleration caused by the narrow channel composed of engine, wing and pylon may cause strong aerodynamic interference. It can be effectively weakened by adjusting the pylon contraction shape based on the near-field pressure distribution. In this way, the shock in the inner side of the pylon can also be eliminated.