Numerical Simulation of Ice-Dust Flow: Effects of Gravity and Cyclic Heat Addition

Abstract

One-dimensional numerical simulations are performed to analyze the ice-dust flow on cometary surfaces under the effect of gravity and cyclic heat addition. The objective is to investigate the ice formation process at the surface of the comet Tempel 1. The numerical model used in this thesis project is a gaseous-granular multiphase model, which describes the interactions of ice, dust, water vapor, and inert gas, and considers an external cyclic heat source and the sublimation and condensation processes between ice and water vapor. Simulations were conducted with different values of gravities. The results show that the ice and dust particles separate and lead to a final state with ice on the top and dust at the bottom. Ice particles are lifted from the ground under the effect of a cyclic heat source in the 0.001g case. Force evaluations show that particle behavior depends mainly on the magnitude of heat-induced forces and gravitational forces. Particle lifting and further separation between ice and dust only occur when the magnitude of heat-induced forces is larger than gravitational forces. These simulations support the hypothesis of ice-surface formation processes on T1.