The chemically reacting hypersonic flow over a reentry capsule with hybrid chemical reaction models.

The accurate prediction of flow characteristics and thermal response characteristics is one of most vital criterion for space vehicles which are flying at very high speeds. These vehicles undergoes severe aerothermodynamics loads during their ascent and descent trajectories. In the present work, we have carried out the DSMC simulation of chemically reacting hypersonic flow over a Crew module Atmospheric Re-entry Experiment (CARE) capsule with five chemical species. A DSMC solver called SPARTA which provide accurate results similar to the Boltzmann equation is used for the present simulation. We have utilized the hybrid chemical reaction model for our simulation which invokes Quantum Kinetic (QK) and Total Collision Energy (TCE) model for modeling the chemical reaction such as dissociation and exchange. The VHS and Larsen-Borgnakke model is used for the modeling of collision and energy exchange reaction. The simulation is carried out with the transitional Knudsen number of 0.1 and the free stream Mach number of 20. The dissociation of N₂ is faster for Hybrid TCE-QK. The independent QK model have higher chemical composition especially for NO composition. The present work demonstrates the hybrid chemical reaction model ensure the faster vibrational equilibrium and better chemistry compared to the independent chemical reaction model. [ABSTRACT FROM AUTHOR]