Aerodynamics of Nose Mounted Propeller Aircraft

Abstract

The thesis deals with the aerodynamic analysis of a nose-mounted propeller aircraft using the flow solver HiFUN. Unsteady RANS simulations using sliding mesh technology is performed on aircraft with the propeller. The study on the aerodynamics of a propeller-driven aircraft is challenging because of the interaction of propeller slipstream with wing and other components, leading to the modi cation of force and moment coefficients of the aircraft, and performance parameters of the propeller as well. The steady code is validated on the aircraft geometry without a propeller, which is also referred as un-powered simulations, against the wind tunnel data provided by the HAL. The unsteady code is then validated on two different propeller geometries, a 2 bladed constant pitch NACA 640 propeller, and a 4 bladed variable pitch propeller, which is relevant to the standard trainer aircraft. The effect of propeller slipstream on aircraft aerodynamics and the installation effects on propeller aerodynamics are studied using CFD. The regions on the aircraft influenced by the propeller slipstream is also identifi ed by the means of pressure plots. The comparison of force and moment coefficients obtained from powered and un-powered simulations are also discussed and this includes a comment on the stability of the aircraft. The results obtained from powered simulations are also compared with the flight stall tests. The work establishes the suitability of the present day CFD tools for the analysis of propeller-driven aircraft, and the need for super-computing platform to accomplish the unsteady power-on simulations.