Numerical investigation of the powered take-off configuration of civil transport using an improved thrust-drag bookkeeping method

Abstract

This paper offers a detailed examination of the powered nacelle’s effect on take-off configuration of a civil transport. Using computational fluid dynamics (CFD) techniques, we analyzed two specific geometries from the Propulsion Aerodynamics Workshop and High-lift Prediction Workshop, comparing our results with existing experimental data. We incorporated configurations of both the Through-flow Nacelle (TFN) and Power Nacelle (PN) for a comprehensive comparison. Our approach significantly refined the prevailing thrust-drag accounting method. Employing surface flow visualizations and spatial particle trajectories, we highlighted the powered nacelle’s influence on the aircraft flow field. Simulations show that the engine exhaust’s flow acceleration boosts lift and reduces flow separation at high angles of attack. However, power intervention notably increases the overall drag. Specifically, at a 14° angle of attack, power effects raise the drag coefficient of the take-off configuration by 275 counts, resulting in a 0.76 decrease in the lift-to-drag ratio.