Flow prediction around a missile with lattice wings using the actuator disc concept

Abstract

This study focusses on the numerical simulation of supersonic flows around a missile with lattice wings. In order to reduce the computational cost for such a configuration, the actuator disc concept is chosen to model the effects of grid fins. This approach is coupled with a Navier-Stokes solver in order to predict the forces and moments on a complete vehicle. The method consists in replacing the lattice controls by artificial boundary conditions where the forces involved by the grid fins are applied. These forces are interpolated from an experimental database. Numerical simulations are performed for laminar and turbulent flows for several Mach numbers and angles of attack. The results are compared to experimental data in order to validate the method. The comparisons reveal some discrepancies which are mainly due to the turbulence effects and to the database from which the forces resulting from the lattice wings are interpolated. The method allows the prediction of the forces applied on the vehicle and therefore an estimate of its aerodynamic performances. The computations validate the approach and show its potential as a tool for vehicle design.