Development of Computational Framework for Store Separation From Cavities

Abstract

tore separation is an active and safety-critical area of research. Before the 1960s, experimentation was considered the only potent way to predict the store separation trajectory. Later, the requirements of store-separation analysis at transonic and supersonic speed pushed the scientific community to explore alternative and more affordable ways of investigation. The maturity of computational resources has paved the way to investigate versatile solutions. This thesis study has been divided into three parts. First, the EGLIN test case’s validation study using Chimera/Overset grid methodology is performed. Three-dimensional Unsteady Reynolds’s Average Navier Stokes equations are solved with a Realizable k- turbulence model. The position, angular orientation, and surface pressure distribution of store results are compared with experimental data, and all the results are in good agreement. Second, a generic stores separation from cavity was carried out, and also the effects of passive flow control devices on the leading edge of the generic cavity are explored. The shear layer and the flow patterns inside the cavities due to flow-control devices are studied. Large-eddy simulations are performed to precisely capture the vortex dynamics. The scenarios considered include a no control device (NCD), rectangular flat-plate control device (RCD), and perforated flat-plate control device (PCD). Third, the efficacy of simulated passive flow control techniques on store separation trajectories is compared. The results indicate that RCD and PCD effectively suppress the pitch-up tendency of the store during separation. However, RCD demonstrated a significant hinge moment, thereby indicating the requirement of a high-torque generating actuator. PCD can be considered as a decent compromise between the store’s pitching moment and hinge-moment.