Sandia Labs FY22 Laboratory Directed Research & Development Annual Report

FY22 ANNUAL REPORT

HYPERSONIC WIND TUNNEL TEST BED FOR FAULT-TOLERANT AND ADAPTIVE CONTROL.

Simulations in fractured media with high geologic realism are needed for both predictions of future geophysical and hydrogeological behaviors, and uncertainty quantifications in many energy and national security-related engineering problems. This Sandia LDRD team developed six new computational capabilities to model multiple physics, including diffusion, transport, and induced polarization in large-scale geologic environments that possess geometrically complex fractures and man-made infrastructure without computational burden, by utilizing the recent developments in the finite element analysis of electromagnetics that allow for the representation of material properties on a hierarchical geometry (Hi-FEM). The team also developed a capability for wellbore integrity monitoring with geo-electric measurements by using the concept of hierarchical material properties. These individual capabilities form a Current hypersonic ground aerodynamics testing is conducted in a static manner. This does not enable study of control system performance or determination of dynamic vehicle behaviors and requires numerous static runs to model the vehicle aerodynamics. To better quantify a dynamic vehicle’s performance, a dynamic control testbed was developed in Sandia’s Hypersonic Wind Tunnel at Mach 8. Models are flown in the tunnel for 30 seconds using different aerodynamic control algorithms. These models have 360 degrees of roll freedom and +/- 5 degrees of pitch and yaw freedom. Trajectories can be simulated by varying the dynamic pressure and by supplementing the total angle of attack with the wind-tunnel static pitching hardware.

Critical to this effort was an academic collaboration with Professor Anirban Mazumdar and his three graduate students from Sandia Alliance partner Georgia Tech. This work has resulted in a Technical Advance and a filed patent. Follow-on funding is being sought to transition the dynamic test capability to other ground test facilities. To date, four invited presentations have been given demonstrating the applicability of this work, including meetings of the National Hypersonic Stakeholders and the American Institute of Aeronautics and Astronautics Defense Conference. A publication documenting this capability is published in the Journal of DOD Research and Engineering . (PI: Katya Casper)

PHYSICALLY RIGOROUS REDUCED-ORDER FLOW MODELS OF FRACTURED SUBSURFACE ENVIRONMENTS WITHOUT EXPLOSIVE COMPUTATIONAL COST

multi-physics simulation tool for complex geologic and engineered environments that can model different physical behaviors by employing a single 3D computational mesh. Fast, high-fidelity multi-physics

Hi-FEM modeling uncovers future opportunities for real time analysis, inverse problems, uncertainty quantification, and the creation of massive, richly textured training sets for machine learning (ML) applications. This project has generated three publications, including being featured on the

cover of The Leading Edge . (PI: G. Didem Beskardes)

Simulation of flow diffusion in a fractured porous medium with embedded complex fractures.

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