Engineering Software for the Evaluation of Unsteady Loading on Store Trajectories

ABSTRACT: We propose to develop and demonstrate a rapid store trajectory analysis tool that uses pre-computed, highly-resolved Detached Eddy Simulation (DES) Computational Fluid Dynamics (CFD) data which has been compressed and stored in an easily reusable and distributable format. The tool will rapidly determine store+bay configurations that display large sensitivity to flow unsteadiness. The technique makes maximum re-use of high-fidelity CFD modeling by storing unsteady bay flow fields using efficient Proper Orthogonal Decomposition based compression techniques, and allows these data compressed flows to be shared and re-used over and over again for fast trajectory fly-outs using existing store trajectory software tools. The database will be adapted for use with engineering force estimation methodologies, such as the Multiple Distributed Airloads model as well as reduced domain unsteady CFD solver based methodologies and will be integrated with the FLIP 4 store-separation trajectory simulation code. This tool will be demonstrated by rapidly performing Monte Carlo type simulations using large numbers of store fly-outs, each starting at different times of the unsteady cavity flow library. In Phase II a master control/scheduler will be developed to run each trajectory on separate processors on DOD HPC resources and produce trajectory statistics, plots and animations from these runs BENEFIT: The schemes and software developed in this effort has applications to a variety of fields including aero-optics, flow control, combustion modeling and biomechanics. It will also be useful to many other areas where the interaction of unsteady flows with objects are important such as weather sensor deployment, relief-aid drops and search and rescue airdrops.