Algorthms and Regolith Erosion Models for the Alert Code

ORBITEC and Duke University have teamed on this STTR to develop the ALERT (Advanced Lunar Exhaust-Regolith Transport) code which will include new developments in modeling of regolith erosion and entrainment as well as plume transport with full mass and momentum conservation. The Plume is handled in a Vlasov formalism with drag force on dust grains, dust equations of motion are solved over a size spectrum. Because of its significant gravity and lack of atmosphere landing on the Moon's surface must involve impingement of the rocket plume directly on the Lunar regolith. The experience in the Apollo landings, both from the perspective of the astronauts viewing surface conditions during decent, and the effects on the exposed surfaces of the Surveyor 3 from the nearby landing of Apollo 12 have alerted us to the importance of good modeling of rocket exhaust plume regolith interactions.