Dadzie, S.K. and Reese, J.M. and McInnes, C.R. (2008) A continuum model of gas flows with localized density variations. Physica A: Statistical Mechanics and its Applications, 387 (24). pp. 60796094. ISSN 03784371

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Abstract
We discuss the kinetic representation of gases and the derivation of macroscopic equations governing the thermomechanical behavior of a dilute gas viewed at the macroscopic level as a continuous medium. We introduce an approach to kinetic theory where spatial distributions of the molecules are incorporated through a meanfreevolume argument. The new kinetic equation derived contains an extra term involving the evolution of this volume, which we attribute to changes in the thermodynamic properties of the medium. Our kinetic equation leads to a macroscopic set of continuum equations in which the gradients of thermodynamic properties, in particular density gradients, impact on diffusive fluxes. New transport terms bearing both convective and diffusive natures arise and are interpreted as purely macroscopic expansion or compression. Our new model is useful for describing gas flows that display nonlocalthermodynamicequilibrium (rarefied gas flows), flows with relatively large variations of macroscopic properties, and/or highly compressible fluid flows.
Item type:  Article 

ID code:  6991 
Keywords:  gas kinetic theory, Boltzmann equation, compressible fluids, NavierStokes equations, rarefied gas dynamics, constitutive relations, Mechanical engineering and machinery, Plasma physics. Ionized gases, Statistics and Probability, Condensed Matter Physics 
Subjects:  Technology > Mechanical engineering and machinery Science > Physics > Plasma physics. Ionized gases 
Department:  Faculty of Engineering > Mechanical and Aerospace Engineering 
Depositing user:  Strathprints Administrator 
Date Deposited:  22 Sep 2008 
Last modified:  18 Jun 2015 10:04 
URI:  http://strathprints.strath.ac.uk/id/eprint/6991 
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