Adjoint Shape Optimization for Continuum-to-Rarefied Gas Flows via the Gas-Kinetic BGK Equation
This concept covers a gradient-based method for optimizing the geometry of a solid boundary immersed in gas flow across all rarefaction regimes, from continuum to free-molecular. The flow is described by the gas-kinetic BGK equation with diffuse reflection on a body-fitted mesh, and the sensitivity of a design objective to the boundary shape is computed with a combined continuous-and-discrete adjoint formulation and driven by a quasi-Newton optimizer, avoiding the many design variables of density-based topology optimization.
Adjoint shape optimization from the continuum to free-molecular gas flows Ruifeng Yuana, Lei Wua,1,∗
This paper proposes an adjoint-based method for optimizing the shape of a solid body immersed in gas flow that works uniformly from the continuum regime to the free-molecular (highly rarefied) regime…