Study of a low-dispersion finite volume scheme in rotorcraft noise prediction

A Low-Dispersion Finite Volume (LDFV) scheme on curvilinear meshes has been applied to one-dimensional wave propagation simulation and rotorcraft noise prediction. This scheme minimizes dispersion error raised in modeling convection phenomena while keeping dissipation error small. It is accomplished by special high order polynomials that interpolate the properties at cell centers to the left and right sides of the cell surfaces. The fundamental one-dimensional wave propagation is simulated to give a direct comparison between the LDFV and existing MUSCL (Monotone Upstream-centered Scheme for Conservation Laws) schemes. Fourier analysis is employed to study numerical error generation and growth presented in the propagation of different frequency wave components with those schemes. The LDFV scheme has been implemented into a version of finite volume code TURNS (Transonic Unsteady Rotor Navier-Stokes) to simulate the High-Speed Impulsive (HSI) noise. A Superbee limiter is introduced to remove high frequency oscillations near the shock waves. Spherically symmetric wave propagation is modeled to investigate the behaviors of the MUSCL and LDFV schemes observed in the HSI noise prediction.