Direct Tomography Simulation for Combustion Flows

In order to develop the next-generation of low-emission energy-efficient combustion devices, high-fidelity computational tools are needed that could enable engineers to maximize efficiency of their designs in a minimal time frame. High-performance exascale simulations of combustion phenomena are critically important to understand and develop novel combustion technologies operating at high pressure and dilution levels, such as low-temperature premixed combustion engines, or supercritical carbon dioxide (sCO2) oxy-fuel combustors. Adopting the current state- of-the-art computational approaches, including Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES), to exascale computing of practical combustion regimes is a challenge since a broader range of dynamic scales needs to be captured to describe interactions and cou- pling between the involved physical and chemical processes at high pressures. To a certain extent, one part of this challenge hinges on the widespread use of domain decomposition tech- niques to parallelize DNS and LES implementations for Euclidean computational domains. It is well appreciated, however, that this parallelization approach may exhibit poor scalability as the number of processor cores increases. The aim of the proposed project is to develop a new class of algorithms suitable for scalable exascale simulation of turbulent reacting flows leveraging, in part, on recent advances in inte- gral geometry methods and computed tomography. The present Phase I research is focused on the demonstration of scalability of the newly developed direct tomography simulation (DTS) approach for canonical 3D nonreacting boundary-value problems. In addition, a series of Di- rect Numerical Simulation (DNS) studies of the sCO2 oxy-methane combustion regime will be performed to generate high-resolution turbulent DNS data sets for validation of the developed simulation algorithms. It is anticipated that potential merits of the proposed approach will include high-fidelity reconstructions of the simulated flow fields in local regions of the compu- tational domain, which would result in greater computational efficiency in comparison to the present DNS and LES approaches. The economical and environmental impacts of combustion are high, and affect important ap- plications in the multi-billion dollar power generation and transportation industries. Advanced combustion technologies are required to address challenges in energy security and demand, as well as in environmental protection and sustainability. The ultimate goal of the project is to deliver a high-fidelity simulation tool that will be used to develop and optimize the next gener- ation of combustion technologies through high-performance computing simulations on exascale platforms.