The presence of suspended dust in the Martian atmosphere is a unique aspect of Mars atmospheric entry that current and future NASA missions to the planet need to address. The dust particles not only interact with the flow field surrounding the entry vehicle as it descends, but also strike its heat shield at high velocities. These interactions can have notable adverse effects, including augmented surface heat fluxes on the vehicle body and increased erosion of the heat shield. The design of thermal protection systems is therefore highly dependent on the expected dust environment of the planet’s atmosphere. Our work focuses on the development of a computational methodology to efficiently and accurately simulate supersonic and hypersonic particle-laden flows over blunt bodies in order to better predict how entry vehicles will interact with the Martian atmosphere and to identify knowledge gaps in how to reliably model such processes.
In computational fluid dynamics, the discontinuous Galerkin (DG) method benefits from high-order accuracy, geometric flexibility, and good scalability to thousands of processors on high-performance computing systems. Another major advantage in hypersonic flow simulation is its significantly lower sensitivity to misalignment between the mesh and strong shocks than the conventional finite-volume method. We employed the DG method to perform simulations of hypersonic dusty flows, and conducted a parametric study to address the lack of experimental data for validation and insufficient knowledge of the important physics at play during a vehicle’s entry into a dusty atmosphere.
High performance computing is critical to perform these large-scale simulations with reasonable cost. Specifically, the well-maintained and well-documented Pleiades supercomputer housed at the NASA advanced Supercomputing (NAS) facility at Ames Research Center. ” – Eric Ching, Stanford University