This Is AuburnElectronic Theses and Dissertations

Numerical Study of High Lift Configurations

Date

2017-07-27

Author

Adhikari, Nirajan

Type of Degree

Master's Thesis

Department

Aerospace Engineering

Abstract

This study investigates the numerical prediction capability of Computational Fluid Dynamics (CFD) in resolving the high-lift aerodynamics. Various numerical aspects in CFD is explored in this research which includes different forms of flow governing equations with variety of turbulence models using TENASI as a CFD solver. The High-Lift Common Research Model (HL-CRM) is used for a grid convergence study in which the effects of grid refinements in resolving the high-lift flow features are studied. Grid refinement shows improvement in the lift prediction. JAXA Semi-Span High Lift Configuration Model (JSM) is also used in this research to investigate the effects of nacelle and pylon installation on a high lift configuration. The wind tunnel test data of JSM is compared with CFD to validate the numerical parameters used for this research. The arbitrary Mach formulation of the governing equations in TENASI failed to predict the stall characteristics. The incompressible solution showed some promising results with accurately predicting the angle of attack for maximum CL but the maximum lift coefficient remains underpredicted. In the linear region of the lift curve, the numerical solution matches experiment data impressively. At a higher angle of attack, unnecessary separation on the upper surface of the wing makes the CFD solution inaccurate. The addition of nacelle and pylon to JSM shows improvements in the lift characteristics in this study and the results are consistent with the experiments.