Direct computation of aeroacoustic fields in laminar flows: Solver development and assessment of wall temperature effects on radiated sound around bluff bodies

Abstract

This work presents results of a direct computation of acoustic fields produced by several laminar flow configurations. A solver specifically developed for compressible mass, momentum and energy equations, named caafoam, is presented. Low–storage high-order Runge-Kutta schemes were used for time integration, and an unstructured colocated finite–volume method for space discretization. A sponge-layer-type non-reflective boundary treatment was adopted to avoid spurious numerical reflections at the far-field boundaries. These techniques were chosen and tested to see if they enable a broad range of physical phenomena, with a particular emphasis on aeroacoustic problems, to be solved. The reliability, efficiency and robustness of caafoam was demonstrated by computing several benchmarks concerning far-field aerodynamic sound. After proving the direct simulation capabilities of caafoam, it was used to analyze the effect of the wall temperature conditions on the aeroacoustic sound produced by laminar flows over bluff bodies.