INTEGRATED CFD-FEA ACOUSTICS WORKFLOW FOR TONAL FAN NOISE SIMULATION: FAR-FIELD PROPAGATION AND DESIGN IMPACT ANALYSIS

For numerous applications, mitigation of ducted fans noise emission is a major design challenge. In the context of aircraft propulsion for example, certification standards have become more stringent over the last decades to support sustainable and environmentally protecting mobility solutions. With current design practices, many physical tests on stationary rigs or during fly-over tests are still required to fulfill all design requirements. Numerical methods have the potential to improve that process by reducing the time and the cost to assess design variants. To be effectively deployed within the industry, these methods must be able to capture the major physical phenomena while offering a competitive computational cost. With this objective in mind, this paper introduces a simulation methodology to predict the tonal fan noise resulting from the rotor-stator interaction and its propagation to the far field environment. With an application to an existing fan design, this paper shows how the workflow establishes a fast and efficient analysis process, by connecting CAD modeling, CFD and FEA simulations in a modular way. Focus will be put on the harmonic balance methodology for CFD simulation of the noise generation, and on the FEMAO methodology for acoustic noise propagation. Results shows a drastic reduction in turnaround time compared to conventional CFD and FEA methods, allowing the entire workflow to be set up and executed within a day of engineering time on an individual workstation.