Comparison of Fully Coupled and DecoupledModeling Results of Graphite Ablation In Hypersonic Flows

Onay, Oğuz
Eyi, Sinan
A thermochemical ablation modeling tool is developed for graphite material in air for reactive hypersonic flows. Multi-species and axisymmetric Navier-Stokes equations are solved for the flow field analysis. Arrhennius type of relations are utilized for finite rate reactions and chemical equilibrium is assumed on the eroding wall of graphite material. Total of thirteen species are included in the analysis in which eight of them are the products of the graphitic material ablation. Flow field, surface thermochemistry and axisymmetric solid conduction analysis models are fully coupled using the energy and mass balance boundary conditions on the reactive wall. Results are compared using the decoupled computational analysis and experimental data in the literature. The comparisons indicate that the coupled analysis approach provides more accurate prediction of ablation rate and wall temperature distributions. However, decoupled method is more practical to implement and provides reasonable accuracy with less computational time.
10th Ankara International Aerospace Conference (18 - 20 Eylül 2019)


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Citation Formats
O. Onay and S. Eyi, “Comparison of Fully Coupled and DecoupledModeling Results of Graphite Ablation In Hypersonic Flows,” Ankara, Türkiye, 2019, vol. 10, Accessed: 00, 2021. [Online]. Available: