Towards Aerodynamic Shape Optimization Using an Immersed Boundary Overset Grid Method

Brandon M Lowe; Chase P Ashby; James R L Koch; David A Craig Penner; Jeffrey A Housman; Jared C Duensing

NASA NTRS · 20240008173

Towards Aerodynamic Shape Optimization Using an Immersed Boundary Overset Grid Method

Brandon M Lowe·Chase P Ashby·James R L Koch·David A Craig Penner·Jeffrey A Housman·Jared C Duensing

Abstract

Traditional Reynolds-averaged Navier-Stokes grid methods applied to aerodynamic shapeoptimization can struggle with the deformation of surface and volume grids at componentintersections, such as at wing-fuselage junctions. To overcome this, we propose an approachwhich utilizes curvilinear overset grids for the discretization of the domain, with the presenceof the body modeled using an immersed boundary method. This approach handles complexgeometries without the need for their explicit integration into the grid. The goal of this approachis to reduce grid generation time and allow for greater geometric freedom for component-basedaerodynamic shape optimization. Two different methods are presented: a source-term-basedand a ghost-node-based immersed boundary method. Flow analyses and adjoint solutionsobtained using the proposed methods show promising comparisons with standard body-fittedgrid methods. Preliminary aerodynamic shape optimization results obtained using one of theimmersed boundary methods are also presented.

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Brandon M Lowe, Chase P Ashby, James R L Koch, David A Craig Penner, Jeffrey A Housman, Jared C Duensing. Towards Aerodynamic Shape Optimization Using an Immersed Boundary Overset Grid Method. https://ntrs.nasa.gov/citations/20240008173

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