Numerical Simulation and Spectral Analysis of Pressure Fluctuations in Vehicle Aerodynamic Noise Generation 2002-01-0597
A new approach is proposed and demonstrated for investigation of the spatial structure of fluctuations in unsteady aerodynamics results obtained using CFD. This approach is used in this study to isolate unsteadiness in the flow field due to coherent structures at relatively high frequency from the dominant organized motion, as well as from the computational noise, in unsteady data obtained from CFD simulations. These simulations are performed using the commercial CFD software, PowerFLOW, which employs a Lattice Boltzmann method and a very large-eddy simulation (VLES) model for small-scale turbulence.
Spectral analysis is performed on the simulation data to compare with experimental results obtained in a wake plane for a simplified vehicle shape. A new frequency band filtering approach is used to visualize pressure fluctuations in the dominant frequency range responsible for aerodynamic noise. This study demonstrates the use of spectral analysis of time-dependent CFD results for examination of unsteady phenomena and aerodynamic noise generation.
Citation: Duncan, B., Sengupta, R., Mallick, S., Shock, R. et al., "Numerical Simulation and Spectral Analysis of Pressure Fluctuations in Vehicle Aerodynamic Noise Generation," SAE Technical Paper 2002-01-0597, 2002, https://doi.org/10.4271/2002-01-0597. Download Citation
Bradley D. Duncan, Raja Sengupta, Swapan Mallick, Rick Shock, D. B. Sims-Williams
Automotive Aerodynamics, Inc., Exa Corporation, University of Durham, School of Engineering
SAE 2002 World Congress & Exhibition
Vehicle Aerodynamics Studies-SP-1667, SAE 2002 Transactions Journal of Passenger Cars - Mechanical Systems-V111-6