Predicting Engine Noise with Computational Aero-Acoustics Model

Computational analysis is being recognized across industry segments as an effective tool to analyze and understand the noise characteristics of Engines. Understanding mechanisms of noise generation can be critical to the effective design and development process of new generation engines. This paper describes Computational Aero-Acoustic analysis performed in ANSYS Fluent to obtain the broad-band and BPF noise sources on a single cylinder Kohler Engine. The inbuilt Fowcs-Williams and Hawkings (FWH) model in ANSYS Fluent was used to optimize the computational model size and turnaround time while maintaining acceptable accuracy of the acoustics results. The targeted frequency range is from 0 to 3000Hz. The results from the simulation are analyzed and compared with data from lab test procedure based on ISO 3744. Data is recorded on 10 receiver locations roughly a meter away from the engine. Repeatable best practices for the solution of aeroacoustics applications using general purpose CFD codes are summarized in the paper.