The operation of rotorcraft entails noise reduction as a crucial concern. To address this issue at its core, an understanding of the aerodynamics near the blades is essential.
Noise source analysis near the blades necessitates the use of Computational Fluid Dynamics (CFD). We have developed an in-house code based on the Actuator Line Method, which eliminates the need to model the entire blade geometry. Instead, it represents the blades as a line, resulting in a reduction in computational time.
For turbulence analysis, we compute the large-scale eddies within the flow field and employ Large-Eddy Simulation (LES) to model small-scale turbulence. LES offers several advantages, including precise predictions, high resolution, and versatility under various conditions, with minimal modeling errors. These attributes render it well-suited for flow analysis near the blades.
Subsequently, the transmission of noise to the receiver or microphone is addressed through the development of an acoustic analogy method rooted in the Farassat Formulation 1A-based Ffowcs Williams-Hawkings (FW-H) approach. This methodology models sound by taking into account the velocity and pressure surrounding high-speed moving bodies, thereby guaranteeing computational accuracy.
FW-H (Ffowcs Wiliams-Hwakings)
Noise Hemisphere in real-time
Actuator Line Method (ALM)
Fluid-Structure Interaction (FSI) delves into the intricate relationship between a movable or deformable structure and the surrounding or internal fluid flow. Grasping this interaction is paramount for accurately predicting how structures will behave in fluid environments. It's noteworthy that FSI analyses typically yield results that are more precise than those obtained from standalone dynamic models. To better understand these complex interactions, our team has employed Large Eddy Simulation, integrating both structural configurations and multibody simulation models. Our ongoing research is centered on enhancing computational fluid dynamics solvers. Additionally, we are in the process of developing a versatile FSI module, designed to adeptly manage a range of fluid-structure scenarios.
