Description: Masten and researchers at the University of Central Florida (UCF) are modeling plume flow effects in simulated lunar and terrestrial environments to develop methods to scale between the two. This innovative work entails: Development of low cost ground testing methods and facilities to produce computational fluid dynamics (CFD) model validation cases for NASA and industry use Size and structure of craters on terrestrial test rig under hot rocket plume conditions. Characterization of lunar surface ejecta particles during rocket powered landings and ascents. Rate of mass ejection from scouring and deep craters Characteristics of ejecta leaving crater (speed, particle sizes, angles) Testing in low gravity, vacuum, and terrestrial conditions will be performed to determine cross calibration and scaling effects for plume effects modeling. Drop tower, ambient, and vacuum engine tests Investigation of scaling in the transition from low thrust scouring to high thrust deep cratering effects and allow scaling of the physics to apply Earth tests to lunar cases. Determination of plume conditions define transition points Determining an algorithm for use in CFD software to accurately model regolith plume effects. Masten and UCF must develop higher-order correlations that capture the actual physics and reduce them to simple algorithms that can be coded in a VOF or similar approach. These scaling relationships have not yet been solved, and currently it is impossible to gain any assurance that a model is correct. Analyzing effects of different regolith simulant types and stratigraphies

Benefits: This work will create a physical model of entrainment mechanisms and use that to validate current landing damage models and reduce uncertainty in regolith emission models from a factor of ten uncertainty (1000%) to ~20% uncertainty. The results will help ensure reliable and safe landings for NASA Artemis and NASA Commercial Lunar Payload Services, without endangering other cislunar assets.

Masten and UCF will provide plume testing services: NASA STMD GCD Plume Surface Interaction group Honeybee Robotics for PlanetVac Purdue University looking at plume interaction with planetary lander structures NASA Flight Opportunities customers PTS Alena lunar lander Made in Space for lunar landing pad development PISCES landing pad NASA JPL for landing assurance tests