New model improves simulation of pressure and temperature distribution around the Mars Rover
The Mars Pathfinder has helped pave the way for Martian exploration, but the rover’s aerodynamics — and thus our ability to optimize its movement on other planets — are not fully understood.
Yu and Hu developed a numerical model to probe the thermochemical nonequilibrium flow around the Mars Pathfinder, a property that affects the temperature and pressure around the vehicle. The authors used numerical simulations to investigate how the different chemical species and reaction types in carbon-dioxide plasma affected the flow parameters of the Mars Pathfinder at different altitudes.
Their model showed the temperature variation around the vehicle that agreed well with past simulation results and uncovered new ones. For example, a subsonic backflow exists at the rear of the Mars Pathfinder, resulting in slightly higher temperatures than other areas, and the temperature was highest at the front of the vehicle, near a point called the “stagnation line.”
“Our numerical simulation of the nonequilibrium flow field of the Mars Pathfinder spacecraft demonstrates good predictive accuracy and application potential,” author Minghao Yu said.
To simulate the flow field, the team used the finite volume method to discretize known flow-field (Navier-Stokes) equations and accounted for the large difference in time scales between chemical reactions and the flow fields with the implicit LU-SGS time advancement algorithm. The authors also solved the equations using the Thomas iteration method.
Future experiments include validating the numerical model with experimental data, expanding the model to consider wall-surface effects, and applying the model to other industries such as catalytic conversion.
Source: “A thermochemical nonequilibrium model of CO2 plasma for studying flow-field properties of the spacecraft Mars Pathfinder,” by Minghao Yu and Zhiqiang Hu, Physics of Fluids (2024). The article can be accessed at https://doi.org/10.1063/5.0216096 .