Development of a Modular Multiphysics Simulation Platform for Aerosol and Particulate Dispersion Modeling

A successful Phase I/Phase II effort will produce a peta and exa-scale capable computational tool for simulating the dynamics, chemical evolution, and motion of aerosol particles (forming the nuclei for water/ice accumulation) to model the complicated dynamics of aircraft wakes. Such a capability is important for various problems associated with aviation that include the formation and dispersion of various pollutants in the atmosphere, the formation of contrails, and aircraft/aircraft engine design (e.g. differences in aircraft fuel). It will also be an important tool that can be used by government entities and commercial stakeholders in efforts to reduce the effects of commercial aircraft on the global climate. The heart of this proposal will be to utilize the DOE developed Flash-X high performance computing framework. Flash-X is a DOE developed software framework designed to enable multiphysics simulations. In phase I, we will combine the capabilities of CGE with Flash-X to model the evolution of aircraft wakes far from the aircraft. A model of aircraft engine exhaust into the flow behind an aircraft will also be added and will include aerosol/soot particles and various, important chemical species. We will modify Flash-X’s Lagrangian particle tracking to specifically handle the motions of aerosol/soot particles that are emitted from aircraft engines or those pre-existing in the atmosphere. In phase I these improvements will include the ability to dynamically create particles, model their growth and/or evaporation (e.g. via accumulation of water/ice), and the effects of external forces on the motion of the particles (e.g. gravity and drag). In Phase II an appropriate chemical reaction network will be added using the existing infrastructure of Flash-X to model important chemical reactions that occur behind an aircraft. This work will be performed in close collaboration with the developers of Flash-X. PI Olson is an original developer of FLASH, the precursor to Flash-X, and is uniquely qualified to perform this work. The proposed modeling software will have broad applicability in fields requiring simulating the long-time evolution of pollutants into the atmosphere. Initial application we will target will be detailed modeling of contrail formation behind a complete model aircraft. This could lead to engineering solutions that may influence aircraft design solutions that could help reduce the warming impact of aircraft contrails. Aircraft engine design is another area where the proposal modeling could be helpful since we will include a careful treatment of ‘soot’ and aerosols that form the condensation nuclei for water/ice in contrails. The proposed modeling could also be used to help commercial airlines to avoid the anticipated additional costs due to penalties imposed by regulatory agencies meant to limit contrail formation. Public benefits will include cleaner air, reduced impacts of contrails on the global climate, and reduced costs to the flying public.