ON THE EFFECT OF SHAPE PARAMETERIZATION ON AEROFOIL SHAPE OPTIMIZATION

Kailash Manohara Selvan

Abstract: The selection of suitable shape parameterization technique is one of the significant factors affecting the fidelity of the solution found during aerofoil shape optimization process. This paper investigates the effect of shape parameterization on an automated aerofoil shape optimization problem. Four well known shape parameterization techniques were considered for study; Bezier curves, Class-Shape function Transformation, Hicks-Henne “Bump” function and polynomial method. A boundary layer panel code was coupled with a surrogate-based multi-objective evolutionary algorithm and implemented within an automatic design loop. The optimization problem was formulated for NACA 0012 aerofoil at 5 degree angle of attack. The main criteria for comparison were based on the number of parameters required by each method for accurate representation of the aerofoil, the ability to find the aerofoil with the best performance within the constrained design space and also the computational cost. Preliminary results show that the optimization process was able to increase the lift-to-drag ratio of the aerofoil by 30%. ClassShape Transformation and Hicks-Henne Bump function were able to find the best aerofoil shape within the design space effectively

Keywords: Aerofoil Optimization, Evolutionary Algorithm, Shape Parameterization

DOI: https://doi.org/10.15623/ijret.2015.0402016