Numerical Solutions to the Fourth And Second Computational Aeroacoustics (CAA) Workshop Benchmark Problems

This paper presents computational fluid dynamics (CFD) solutions to problems concerning sound generation by viscous flows. Two of CAA Workshop benchmark problems have been studied in this paper and they are Problem 2 of Category 5 of the fourth CAA Workshop benchmark problems and Category 4 of the second CAA Workshop benchmark problems. The former solution is to study aerodynamic sound generated by a viscous airflow over a rectangular cavity, and the latter solution is to study Aeolian tones created by a viscous airflow over a circular cylinder. Both solutions were computed by a Navier-Stokes flow solver TIDAL (Time Iterative Density/pressure based Algorithm) developed at Boeing Rocketdyne Division. The numerical algorithm of TIDAL used in this study is based on a dual-time stepping scheme for temporal discretization and a third-order finite-volume scheme for spatial discretization. The aims of this study are (1) to apply TIDAL to solve aero/acoustic problems of sound generation by viscous flows, and (2) to validate the computed solutions with the experimental data of benchmark problems for certifying TIDAL for future aero/acoustic computations of noise sources.