Numerical Simulation and Investigation of the Effects of Vortex Generator on Aerodynamic Coefficients of the Main Helicopter Rotor in Hover

Farajollahi, Amirhamzeh; Niavarani, Bijan; Rostami, Mohsen; Naderi, Ali Asghar; Bagherpour, Farid

Numerical Simulation and Investigation of the Effects of Vortex Generator on Aerodynamic Coefficients of the Main Helicopter Rotor in Hover

Document Type : Original Article

Authors

amirhamzeh farajollahi ¹

bijan niavarani ²

Mohsen Rostami ¹

ali asghar naderi ¹

farid bagherpour ³

¹ Assistant Professor, Imam Ali University, Tehran, Iran

² Master's student, University of Science and Technology, Tehran, Iran

³ PhD student, Imam Ali University, Tehran, Iran

Abstract

In present study, the effect of vortex generators on the aerodynamic forces of a helicopter's main rotor in hover is investigated. Vortices around blades have a significant effect on noise and aerodynamic forces. Using vortex generators is an appropriate method for decreasing the influence of flow separation and vortex around a rotor. In this study, vortex generators include four different arrangements. The numerical simulation procedure of main rotors of the helicopter blades is done by using Fluent software. The mesh grid is used in the form of unstructured. A validation with Cardona and Tang results is done. For this reason, NACA 0012 airfoil and an attack angle of 8° are used for the blades of the main rotor. It can be revealed from the results that using vortex generators, a decrease in vortex power and dimensions of transverse vortices has occurred. Also, the results show that the thrust coefficient and torque coefficient of the helicopter blades compared to the non-vortex generators mode has increased and decreased, respectively.

Keywords

Vortex generator

Numerical simulation

Aerodynamic coefficients

Hover

20.1001.1.23223278.1400.10.2.4.1

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