Two-dimensional ablation in cylindrical geometry

Ablation modeling in cylindrical geometry is a very important problem in th e thermal modeling, of spacecraft, which has not been dealt with adequately in the literature. In the present work, two-dimensional ablation In cylind rical geometry is considered when the incident heat flux varies axially as well as temporally. A novel idea of using an effective inverse Stefan numbe r, which is analogous to the effective heat of ablation (used in the Litera ture), is proposed to be used as a variable nondimensional latent heat of a blation for ablation modeling, indirectly accounting for various processes involved in ablation. A two-dimensional ablation problem is solved by an al ternating direction implicit and adjustable time-step scheme, coupled with boundary immobilization. Quasi-one-dimensional and two-dimensional modeling methods have been compared for two different materials, and the effects of variation of the proposed inverse Stefan number with the incident heat flu x and the presence of highly conducting structure bonded to the ablative ma terial have been studied. An optimum modeling method under specific conditi ons is suggested.