Aerodynamic Performance Optimization of the Bell-212 Rotor: a CFD-Based Investigation of Tip Airfoil Integration

Abstract

This study aims to optimize the blade design of the BELL-212 helicopter rotor to enhance its aerodynamic performance, particularly during hover flight conditions. By employing advanced Computational Fluid Dynamics (CFD) simulations, the research analyses the aerodynamic behavior of three distinct airfoil geometries: the NACA 0012, representing the baseline rotor design, the NACA 0006, and the NASA SC(20)-712. These airfoils were selected for this study because the NACA 0006 represents a thinner variation of the NACA 0012, while the NASA SC(20)-712 is a supercritical airfoil with a slender profile, making it well-suited for transonic airflow conditions typically encountered by tip blades. The investigation primarily focuses on maximizing thrust generation while simultaneously minimizing drag and mitigating tip vortices, regions of high velocity that significantly impact performance and efficiency. Through detailed simulations, the study provides valuable insights into vortex distribution and flow separation around the tip blade surfaces. The results demonstrated notable improvements in lift force, accompanied by a slight reduction in drag and enhanced rotor stability. Comparative evaluations across the tested geometries led to the identification of an optimized blade design, offering superior aerodynamic efficiency and overall performance. This work proposes an innovative framework for rotor blade design, contributing to advancements in helicopter performance during hover flight.