Prediction of the Pitch Angle Value for the BELL’s 212 Helicopter Main Rotor in a Hover State Configuration Using a CFD Approach

Abstract

This research investigates the aerodynamic behavior of the main rotor of the BELL-212 helicopter during stationary flight, focusing on calculating the minimum pitch angle required to support its weight and ensure stable hover, thereby enhancing pilot safety. This article opens with a theoretical analysis utilizing Momentum and Blade Element theories in order to determine the pitch angle necessary for achieving hover conditions. This theoretical value has served as a baseline for the Computational Fluid Dynamics (CFD) approach and a benchmark for model validation throughout our simulations. The CAD SOLIDWORKS program has been subsequently used to model the primary rotor geometry of the BELL-212 helicopter. Then the rotor coordinates have been imported into the ANSYS software, which has allowed meshing the computational domain so that the FLUENT solver can be used to execute the CFD simulation. The Computational Fluid Dynamics analysis has played a pivotal role in visualizing the flow around the rotor and evaluating its aerodynamic performance. Multiple simulation tests have been conducted at varying pitch angles in order to identify the optimal θ value that allows the rotor to generate sufficient thrust for hovering. The results from both theoretical and CFD approaches have been validated through comparative analysis, demonstrating a good agreement within an acceptable margin of error, thus confirming the reliability of our calculations.