Surface roughness and radiative heat transfer effects on the ablative behavior of a graphite nozzle are studied. A validated numerical approach, that relies on a full Navier-Stokes flow solver coupled with a thermochemical ablation model is used for the analysis. A modification of the Spalart-Allmaras turbulence model is implemented to account for surface roughness. Different simplified models are used to evaluate the integral emissivity in case of metallized propellants and the net radiative heat flux is considered in the surface energy balance. Individual and combined effects of these phenomena are analyzed. Results show that the influence of surface roughness and radiation heat transfer on the erosion rate is dependent on the erosion regime.
Radiation and Roughness Effects on the Thermochemical Erosion of Ablative Materials in Rocket Nozzles / Turchi, Alessandro; Bianchi, Daniele; Piyush, Thakre; Nasuti, Francesco; Vigor, Yang. - ELETTRONICO. - (2013), pp. 1-16. (Intervento presentato al convegno 51st AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition tenutosi a Grapevine (Dallas/Ft. Worth Region), Texas, USA nel 7-11 gennaio 2013) [10.2514/6.2013-186].
Radiation and Roughness Effects on the Thermochemical Erosion of Ablative Materials in Rocket Nozzles
TURCHI, Alessandro;BIANCHI, DANIELE;NASUTI, Francesco;
2013
Abstract
Surface roughness and radiative heat transfer effects on the ablative behavior of a graphite nozzle are studied. A validated numerical approach, that relies on a full Navier-Stokes flow solver coupled with a thermochemical ablation model is used for the analysis. A modification of the Spalart-Allmaras turbulence model is implemented to account for surface roughness. Different simplified models are used to evaluate the integral emissivity in case of metallized propellants and the net radiative heat flux is considered in the surface energy balance. Individual and combined effects of these phenomena are analyzed. Results show that the influence of surface roughness and radiation heat transfer on the erosion rate is dependent on the erosion regime.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
