Development and Fidelity Assessment of Potential Flow based Framework for Aerodynamic Modeling of High Lift Devices

Abstract

High lift devices play a vital role in dictating the accelerated performance of an aircraft for different flight phases such as takeoff, landing, and aerobatic maneuvers. The aerodynamic design of high lift devices for any particular aircraft is an iterative process and is achieved through extensive aerodynamic Analysis of the aircraft for various flap configurations. Computational Fluid Dynamics (CFD) and Wind tunnel testing are highly effective techniques for performing the required Analysis, yet they have high computational costs and time. To overcome this shortcoming, a robust framework based on potential flow solver (PFS) and geometry parameterization is required without compromising the fidelity of the Analysis. This research aims to develop a highly robust aerodynamic analysis framework based on the Vortex Lattice Method (VLM) coupled with Polhamus Suction Analogy and parametric modeling of high lift devices. The fidelity of the framework is validated through experimental testing and is quantified by developing a fidelity assessment matrix. It is established that the computational cost of CFD has been reduced three times with only a 10% to 20% loss in accuracy when the developed framework is used. The developed PFS framework gives results from 80% to 90%. The framework results for a reference aircraft are thoroughly compared with CFD analyses. The framework provides values that agree with corresponding CFD analyses in a fraction of the time.

Keywords

• Analytical Solver; Vortex Lattice Method (VLM); Wind-tunnel, Computational Fluid Dynamics (CFD), Potential Flow Solver (PFS), High Lift Devices (HLD), Medium Altitude Long Endurance (MALE), Unmanned Aerial Vehicle (UAV)