Prediction of Store Trajectory Response to Unsteady Aerodynamic Loads

We are proposing an approach to the use of CFD that will include the determination of large scale unsteadiness in the flow over the weapons bay. The effects of release of the weapon, the unsteady aerodynamic forces on a given weapon as it leaves the bay and its continued descent will be determined. Metrics for both the large scale unsteadiness associated with flow over the bay, as well as metrics for the influence of such unsteadiness on a given weapon will be produced. One of the motivations for these simulations is to determine which weapon/bay combinations are likely to have erratic trajectory outcomes – one release behaving substantially different than the next. The second motivation is to define the bay/ weapon metrics that predict the probability of these erratic trajectories. The final important aspect of the approach is to achieve these objectives in orders of magnitude less computing time than would be required if a standard, straight forward time accurate simulation were used. The straight forward approach being the bay/weapon release and descent trajectory computed for a collection of different weapons and multiple releases for each weapon.