Analytical and Kinetic Modeling of Ablation Process (Preprint)

Abstract

One of the most important issues in CFD modeling of ablation process is the formulation of boundary conditions at the gas-surface interface. These boundary conditions cannot be obtained without analytical or parametric numerical modeling of the Knudsen layer formed near the evaporating surface. Analytical models are therefore of interest for numerical simulation of ablating flows. Recently Pekker, Keidar, and Cambier developed a new analytical model of the Knudsen layer, which takes into account the temperature gradient in the bulk gas. This model uses a bimodal velocity distribution function which preserves the laws of conservation of mass, momentum, and energy within the Knudsen layer and converges to the Chapman-Enskog velocity distribution function at the outer boundary of the Knudsen layer. The main objective of this work is to provide detailed analysis of the applicability of this analytical model of the Knudsen layer through comparison of results with the numerical solutions of the ES-BGK model kinetic equation and DSMC results.

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Document Details

Document Type
Technical Report
Publication Date
May 05, 2008
Accession Number
ADA483677

Entities

People

  • L. Pekker
  • N. Gimelshein
  • S. Gimelshein

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Ablation
  • Air Force Research Laboratories
  • Boltzmann Equation
  • Boundaries
  • Coefficients
  • Computational Fluid Dynamics
  • Computational Science
  • Conduction (Heat Transfer)
  • Distribution Functions
  • Energy
  • Equations
  • Heat Transfer
  • Knudsen Number
  • Momentum
  • Monte Carlo Method
  • Temperature Gradients
  • Thermal Conductivity

Fields of Study

  • Physics

Readers

  • Aerospace Propulsion Engineering.
  • Computational Fluid Dynamics (CFD)
  • Fluid Dynamics.