Entropy production in boundary layers
نویسندگان
چکیده
منابع مشابه
Entropy boundary layers
We consider the Euler system of compressible and entropic gaz dynamics in a bounded open domain of R with wall boundary condition. We prove the existence and the stability of families of solutions which correspond to a ground state plus a large entropy boundary layer. The ground state is a solution of the Euler system which satisfies some explicit additional conditions on the boundary. These co...
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A one-dimensional divergence of the monochromatic heat flux for wall-affected attenuating thingas, is developed from general considerations. Here Ebl. K~ cy and r, respectively denote the monochromatic values of the emissive power, absorption coefficient of gas, wall emissivity and optical thickness; , E, is the second exponential integ-ral, y the -4' coordinate normal to boundary. infinite geo...
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In an earlier paper in Entropy [1] we hypothesized that the entropy generation rate is the driving force for boundary layer transition from laminar to turbulent flow. Subsequently, with our colleagues we have examined the prediction of entropy generation during such transitions [2,3]. We found that reasonable predictions for engineering purposes could be obtained for flows with negligible strea...
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The prediction of the entropy generation rate in laminar shear layers is treated as steady, even in the presence of high levels of free stream turbulence. Here we highlight the deficiencies of this approach by quantifying the magnitude of entropy generation rate fluctuations in the laminar boundary layer subjected to free stream turbulence. We find fluctuation levels in excess of 100% in the ne...
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ژورنال
عنوان ژورنال: Journal of Thermophysics and Heat Transfer
سال: 1990
ISSN: 0887-8722,1533-6808
DOI: 10.2514/3.197