Diffusive limits for linear transport equations

Journal Article · Sat Oct 31 23:00:00 EST 1992 · Nuclear Science and Engineering; (United States)

OSTI ID:7016043

Pomraning, G C ^[1]

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1. California Univ., Los Angeles, CA (United States). School of Engineering and Applied Science

The authors show that the Hibert and Chapman-Enskog asymptotic treatments that reduce the nonlinear Boltzmann equation to the Euler and Navier-Stokes fluid equations have analogs in linear transport theory. In this linear setting, these fluid limits are described by diffusion equations, involving familiar and less familiar diffusion coefficients. Because of the linearity extant, one can carry out explicitly the initial and boundary layer analyses required to obtain asymptotically consistent initial and boundary conditions for the diffusion equations. In particular, the effects of boundary curvature and boundary condition variation along the surface can be included in the boundary layer analysis. A brief review of heuristic (nonasymptotic) diffusion description derivations is also included in our discussion.

• OSTI ID: 7016043
• Journal Information: Nuclear Science and Engineering; (United States), Journal Name: Nuclear Science and Engineering; (United States) Vol. 112:3; ISSN NSENAO; ISSN 0029-5639
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
661300 -- Other Aspects of Physical Science-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ASYMPTOTIC SOLUTIONS
BOLTZMANN EQUATION
BOUNDARY CONDITIONS
BOUNDARY LAYERS
CHAPMAN-ENSKOG THEORY
DIFFERENTIAL EQUATIONS
DIFFUSION
DOCUMENT TYPES
EQUATIONS
FLUIDS
HILBERT TRANSFORMATION
INTEGRAL TRANSFORMATIONS
LAYERS
NAVIER-STOKES EQUATIONS
NONLINEAR PROBLEMS
PARTIAL DIFFERENTIAL EQUATIONS
REVIEWS
TRANSFORMATIONS
TRANSPORT THEORY