An alternative wind tunnel data correction based on CFD and experimental data in the transonic flow regime

Abstract

This paper presents an alternative approach to correct wind tunnel data through the use of CFD solutions. The correction is based on the difference between the measured pressures in the wind tunnel and the pressures predicted with CFD in free flow condition, at angles of attack and Mach numbers surround the wind tunnel data point. Optimization is used to find the combination of angle of attack and Mach number that minimizes the difference between the measured pressures and the predicted pressures. A surrogate model is used to approximate the CFD data to enhance the computational efficiency of the approach. The result of the optimization is a corrected angle of attack and Mach number that corresponds to a pressure distribution under free flight conditions that best fits the wind tunnel experiment in terms of the objective function used. It is demonstrated that when all wing pressures are used in the objective function the resulting corrections are in agreement with wall interference corrections as predicted with a wall pressure signature method.