Computational investigation of propulsion interaction effects on wing propeller installation

This paper investigates the feasibility of applying a multi-purpose CFD code to the analysis of unsteady flow due to the aerodynamic interaction of propeller and airframe configurations. Computationally inexpensive algorithms and meshes are employed to demonstrate the concept. As a preliminary test of the method, the case of an isolated six-bladed propeller and nacelle at incidence is modelled. The three dimensional, time dependent flow field is predicted by solving the incompressible Euler equations and periodic variations in torque and thrust are observed. A two-bladed propeller and a simple nacelle, mounted on a wing, are then modelled using the same level of physical modelling, and fully-coupled solutions of the mutually-interacting aerodynamic flow field are obtained. Again, unsteady effects are observed. In particular, strong fluctuations in the lift on the wing are predicted. The results confirm that the approach is feasible and that the method is worthy of further development, with extension to more sophisticated solutions and, if possible, comparisons with measurement.