Nikita D. Ageev , Alexander A. Pavlenko
DOI Number XXX-YYY-ZZZ
Conference Number HiSST 2018_600969
At the present time two main approaches to aerodynamic shape optimization may be distinguished. The first approach requires only direct calculations. The second one expects the availability of tools for the evaluation of the constraint and objective function gradients. The first approach is robust and has opportunities for the topological optimization. The second one allows to operate with large number of design variables. To achieve high aerodynamic efficiency, it is proposed to combine these approaches in two-stage optimization process. The purpose of the work is the development of this technique. The planar inviscid symmetric problem of the optimization of the constrained area airfoil with sharp leading edge is solved. The results are in good agreement with the data previously obtained by other researchers. The relative drag residual equals 1%. The developed technique is used for aerodynamic optimization of the body of revolution at Mach number of 1.8. The Sears-Haack body is used as a baseline configuration. The body shape variation is realized at the first stage with the deforming spline through 5 points and at the second stage with the free-form deformation box of 101×2 control points. Flow simulation is carried out by way of the numerical solution of RANS equations with closure of differential turbulence models SA and SST. The continuous adjoint solver is used for gradient evaluation. Heuristic algorithm of indirect optimization based on self-organization is involved at the first stage and sequential quadratic programming – at the second stage. Total drag reduction of 22% is reached (19% at the first stage, 3% at the second stage). Drag reduction is achieved due to the volume transfer from front part of the body to the rear one at both stages.