A methodology coupling the LeMANS flow solver to the MOPAR-MD material response solver is presented, enabling fully-coupled, conjugate, two-dimensional simulations of ablation of pyrolyzing materials in rocket nozzle applications. Five different treatments of the surface energy balance are presented, with increasing levels of fidelity. One of these methods eliminates transport coefficient assumptions and the need for pre-computed B' tables by directly using species diffusion at the ablating wall to compute char mass flux. Equilibrium surface chemistry is assumed; these calculations are performed using the MUTATION++ library. Ablation of the HIPPO nozzle test case is investigated using decoupled and conjugate analysis methods. A new baseline decoupled analysis is presented and compared to experimental data. Conjugate simulations are also performed using five different surface energy balance approaches and compared to the decoupled analysis results. The integrated equilibrium chemistry approach can fully capture the effects of ablation product species injection into the nozzle flowfield, in addition to the effects of recession, wall temperature, and blowing. By rigorously capturing the strong interactions and dependencies that exist between the reacting flowfield and the ablating material, improved analysis accuracy is anticipated.
展开▼
