Numerical modeling of transient plume impingement during high altitude rocket staging

摘要

The direct simulation Monte Carlo (DSMC) method is used to model a transient stage separation of a generic sounding rocket at 100 km. Lower stage movement is included, and the flow and surface properties are simulated over the first second after thruster ignition. Both liquid and solid propellant thrusters are examined with a thrust of 25 kN and 34 kN, respectively. Four different simulation scenarios are considered that allow analysis of the impact of the stage motion, explcitly including unsteady flow effects. Unsteady flow effects are small enough that quasi-steady state modeling appears to be adequate for this general staging scenario. The influence of DSMC statistical fluctuations on the stage trajectory is insignificant compared to the total contribution of the plume force. We also examine the radiation environment, including the plume-atmosphere shock and plume-lower stage impingement.