Illinois wins competitive research grant to model surface cratering, ejecta during final descent of rocket-powered lander

During a lunar landing, the rocket engine exhaust kicks up a lot of dust and loose rock, or regolith, on the surface. This can cause damage to anything nearby as well as the spacecraft itself. Laura Villafañe Roca has been studying the complex physics surrounding this plume-surface interaction. She received a NASA Early Stage Innovations award to continue the work in new ways. 

Villafañe is an assistant professor in the Department of Aerospace Engineering at the University of Illinois Urbana-Champaign. The goal of Early Stage Innovations is to accelerate the development of groundbreaking, high-risk/high-payoff space technologies to support the future space science and exploration needs of NASA, other government agencies, and the commercial space sector. Co-investigators on the project are AE faculty member Fabien Evrard and Jesse Capecelatro from the University of Michigan.

The team will use data from tests performed by NASA during a 2021-2022 test campaign in a large vacuum chamber that included various flow and regolith parameters to simulate different landing scenarios. They will also use data from tests performed at UIUC in the EPLab vacuum chamber under similar test parameters. Both sets of data are complementary and represent a Mach 5 jet impinging on regolith surfaces for different planetary atmospheres. They will extract the most relevant quantities of interest for cratering, erosion, and ejecta from the large volume of high-speed imagery and parametric experimental data, and to use them to derive closed-form models for plume-surface interaction phenomena.

“We will be combining advanced image and data processing and classification tools with machine learning algorithms to obtain models and engineering relations that reproduce the phenomenology of crater growth, surface erosion and ejecta dynamics, This will help us better understand the different erosion regimes that may dominate depending on the terrain and rocket plume properties, and build engineering relations that can be used for predictions of what to expect during a landing” Villafañe said.

She said the goal of the research is to advance the understanding of the complex phenomena taking place during landings on a regolith surface. The knowledge gained will inform mission design, risk mitigation strategies, and make more accurate predictions.