PSAAP3@Illinois:  The Center for Exascale-enabled Scramjet Design

The talk will overview the integrated predictive science efforts in the Illinois PSAAP3 Center, which targets the analysis and design of composite scramjet engines for hypersonic propulsion.  This will include the experimental prediction target, the physical models and their corresponding physics-targeted experiments, the numerical techniques, software strategies, the computer science methodology in which the simulation tools are being developed, and the center management approach.  This high-level overview will provide deeper dives into the technical details of two fluid mechanics related subprojects .  In the first, the adjoint governing equations are used in conjunction with a neural network back-propagation algorithm to train sub-grid-scale models for turbulence, particles, and flames.  Models trained with such a "full" physical constraint are confirmed to be both accurate and robust in simulations.  The other deep dive will present an analysis of the flow created by a laser-induced optical breakdown of a gas, as might be used as an ignition source or flow control.  Under some conditions, this can lead to a curious jetting behavior that expels hot fluid a significant distance from the nominal focal point.  The vorticity generation and interactions leading to the jetting and its direction will be analyzed.