Modeling &
simulation

GTL's Universal Combustion Device Stability (UCDS) model — rooted in Chief Engineer Dr. Gary Flandro's 40+ years of combustion-instability research — provides an unprecedented ability to accurately predict the stability of steady-flow combustion devices. Dr. Josh Batterson and Dr. Eric Jacob have continued Dr. Flandro's work, extending UCDS to include full multi-physics numerical simulation, nonlinear wave-steepening, and CFD CI post processing analysis.

Rather than discovering instability on the test stand, UCDS lets GTL design in a high stability margin from the outset — the insight behind the Superior Stability Engine.

GTL applies coupled multiphysics modeling — fluid dynamics, structural, and thermal analysis — to aerospace systems operating in extreme environments, from cryogenic tankage to high-temperature propulsion, linking the physics that conventional single-discipline tools treat in isolation.

This work is led by Dr. Josh Batterson, GTL's Director of Modeling & Simulation, whose custom multiphysics framework couples a compressible reacting-flow CFD solver with conjugate heat transfer, acoustics, and structural mechanics — spanning acoustic, vorticity, thermal, and hydrodynamic wave solvers, genetic algorithms, smoothed-particle hydrodynamics, and structural mechanics.

SimDAT is GTL's simulation data-analysis toolset. Starting from the unsteady flow field, it decomposes the solution into individual acoustic and hydrodynamic modes, then localizes where sound is generated — isolating the vortex-shedding and heat-release sources that drive combustion instability. This methodology is detailed in our AIAA-JPP publication.