Optimization of a low Reynold's number 2-D inflatable airfoil section
by Johansen, Todd A., M.S., UTAH STATE UNIVERSITY, 2011, 73 pages; 1490498

Abstract:

A stand-alone genetic algorithm (GA) and an surrogate-based optimization (SBO) combined with a GA were compared for accuracy and performance. Comparisons took place using the Ackley Function and Rastrigin's Function, two functions with multiple local maxima and minima that could cause problems for more traditional optimization methods, such as a gradient-based method. The GA and SBO with GA were applied to the functions through a fortran interface and it was found that the SBO could use the same number of function evaluations as the GA and achieve at least 5 orders of magnitude greater accuracy through the use of surrogate evaluations.

The two optimization methods were used in conjunction with computational fluid dynamics (CFD) analysis to optimize the shape of a bumpy airfoil section. Results of optimization showed that the use of an SBO can save up to 553 hours of CPU time on 196 cores when compared to the GA through the use of surrogate evaluations. Results also show the SBO can achieve greater accuracy than the GA in a shorter amount of time, and the SBO can reduce the negative effects of noise in the simulation data while the GA cannot.

 
AdviserThomas Hauser
SchoolUTAH STATE UNIVERSITY
SourceMAI/ 49-04, p. , Apr 2011
Source TypeThesis
SubjectsAerospace engineering; Mechanical engineering
Publication Number1490498
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