Numerical Analysis of an Isolated Main Helicopter Rotor in Hovering and Forward Flight

Abstract

Aerodynamic characteristics of a 5-seater helicopter with different rotor configuration (i.e.; blade number and size) operating in forward flight mode were simulated by using commercial computational fluid dynamic (CFD) software called FLUENT. The main objective of this simulation is to calculate the aerodynamic load generated by rotor during hovering and different forward flight speed range. The effects of using different rotor configuration and shaft rotational speed (different engine selection) includes in this simulation. For CFD analysis, the multiple references rotating frame method (MRF) with standard viscous k-e turbulent flow model was used on modelling the rotating rotor operating both in hovering and forward flight. To simulate the helicopter operating in the trim condition, the main rotor collective pitch, coning and flapping angle was calculated based on the blade element theory (BET). The blade is assumed stationary and blade collective pitch, coning and flapping angle was positioned as calculated using BET. For this purpose CFD simulation has been compared with the corresponding results obtained from BET analysis and that found they were in good agreements.