CFD Based Response Surface Modeling with an Application in Missile Aerodynamics

A. Emre Cetiner, Bedri Yagiz, Goktan Guzel, Onur Ozgur, and Ilteris Koc (Aselsan INC)

CHALLENGE - In engineering, simulation for a complex geometry or a configuration can take hours or even days, since it is not always possible to reduce the complexity of the problem and to obtain a model that can be solved quickly. This limits the number of simulations, hence restricts the design space exploration of the geometry. In this study, steps to generate reliable Response Surface Models based on Computational Fluid Dynamics simulations are explained with an application to a newly designed missile at Aselsan Inc.

SOLUTION - Certain commercially available software, i.e. modeFRONTIER of ESTECO and FLUENT of ANSYS, are utilized in this study. Starting from an initial distribution of design points that are decided by a Uniform Latin Hypercube algorithm, a Sequential Sampling method is followed to improve the final Response Surface Models. The quality of the RSMs are reported by monitoring the convergence histories of mean normalized errors that are computed using previously simulated design points. Moreover, outputs of Response Surface Models and Computational Fluid Dynamics analyses are compared for some cases. 

BENEFITS - For validation of the RSMs, mean normalized errors are calculated and reported by using validation points. Finally, for some cases the RSM results and CFD results are compared. RSMs predict lift and drag coefficients very well. Moreover, RSMs predict side force, 3 moments and hinge moment coefficients in an acceptable error range.