A 3D frequency-domain linearised Euler solver based on the Goldstein acoustic analogy equations for the study of non- uniform mean flow propagation effects

摘要

For modelling sound propagation through non-uniform mean flows, a new scalable Adjoint Linearised Euler solver in the frequency domain is developed which extends the work of Karabasov and Hynes (2006) to fully three dimensional flows. The solver is based on second-order central finite differences and pseudo-time stepping based on iterative Adams-type. A special preconditioning technique based on the variable iteration time step is used to avoid numerical instability associated with shear-layer type flows. Numerical results are verified against the analytical solution corresponding to planar acoustic wave scattering from the parallel jet flow.