Flow Analysis of A Helicopter Main Rotor With Gurney Flaps

The helicopter is a revolutionary machine which is developed with a high degree of complexity and remarkable capabilities when comparing with a fixed wing aircrafts. Bell 212 is a medium utility helicopter with 15 seats capacity of one pilot and 14 passengers. It has twin engine and a two bladed main rotor and two blade tail rotor. Main rotor diameter is 14.69m (48ft). Max thickness 12% at 30% chord (C). Chord length of the NACA (National Committee for Aeronautics) 0012 is 23.38 inches. A 1:1 main rotor of bell 212 was designed in ANSYS design modeler was used to generate computational mesh and subsequent computational fluid dynamics (CFD) simulations were performed mainly with ANSYS Fluent. Gurney flaps are micro tabs which are used for lift enhancement by attaching it at the end of the trailing edge of the airfoil. The gurney flap height of 3% of the chord and thickness of 0.33% C at 45 º angle is used for its efficient lift increment. The project work is been analyzed with two cases, forward flight for determining coefficient of lift (CL) and drag (CD) and hovering flight for thrust has been performed. The two cases of flight has been analyzed for both main rotor with and without gurney flaps and compared to determine the better results. It is expected to increase the coefficient of lift to drag ratio with gurney flaps attached to overall span of the helicopter main rotor.