University of Toronto
                  PDE/Applied Math/Analysis Seminar
                    Friday March 24, 3:10-4pm
                          6183 Bahen Center      



SPEAKER:  Yann Bernard

TITLE:	  Anomalous limit-behavior for the Knudsen gas in a thin channel
	  with accommodation.

ABSTRACT: We study a free molecular flow in a thin channel bounded by
	  parallel plates on which Maxwellian boundary conditions with
	  accommodation apply. It is well-known that that as the width
	  of the channel goes to zero, the evolution of the number
	  density is described by a diffusion equation. That was
	  proved using tools from probability theory by Borgers et
	  al. We give an alternate proof based on functional analytic
	  techniques and compactness arguments. In addition, we will
	  show that if the accommodation vanishes in a certain
	  prescribed way, the density function obeys a BGK-like
	  equation. This is in contrast with the "discrete" (in the
	  velocity sense) counterpart of this problem, for which the
	  density follows a telegraphy equation.

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University of Toronto PDE/Applied Math/Analysis Seminar 
http://www.math.toronto.edu/appmath/

2005-2006 organizers:
          Pieter Blue           pblue@ math.toronto.edu
          Almut Burchard        almut@ math.toronto.edu
          Bob Jerrard           rjerrard@ math.toronto.edu
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