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Nearly free molecular heat transfer from a sphere


Schmulian, Robert Jay (1968) Nearly free molecular heat transfer from a sphere. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/KZ16-1X08.


Consider a sphere immersed in a rarefied monatomic gas with zero mean flow. The distribution function of the molecules at infinity is chosen to be a Maxwellian. The boundary condition at the body is diffuse reflection with perfect accommodation to the surface temperature. The microscopic flow of particles about the sphere is modeled kinetically by the Boltzmann equation with the Krook collision term. Appropriate normalizations in the near and far fields lead to a perturbation solution of the problem, expanded in terms of the ratio of body diameter to mean free path (inverse Knudsen number). The distribution function is found directly in each region, and intermediate matching is demonstrated. The heat transfer from the sphere is then calculated as an integral over this distribution function in the inner region. Final results indicate that the heat transfer may at first increase over its free flow value before falling to the continuum level.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Applied Mathematics
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Applied Mathematics
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Cole, Julian D.
Thesis Committee:
  • Unknown, Unknown
Defense Date:7 May 1968
Record Number:CaltechTHESIS:04052013-154128630
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7582
Deposited By: Benjamin Perez
Deposited On:05 Apr 2013 23:23
Last Modified:09 Nov 2022 19:20

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