Accession Number : AD0771483

Title :   Large Amplitude Convection in Porous Media.

Descriptive Note : Rept. for Apr-Aug 73,


Personal Author(s) : Straus,Joe M.

Report Date : 15 DEC 1973

Pagination or Media Count : 35

Abstract : The properties of convective flow driven by an adverse temperature gradient in a fluid-filled porous medium are investigated. The Galerkin technique is used to treat the steady state two dimensional problem for Rayleigh numbers as large as ten times the critical value. The flow is found to look very much like ordinary Benard Convection, but the Nusselt number depends much more strongly on the Rayleigh number than in Benard convection. The stability of the finite amplitude two dimensional solutions is treated. At a given value of the Rayleigh number, stable two dimensional flow is possible for a finite band of horizontal wavenumbers as long as the Rayleigh number is small enough. For Rayleigh numbers larger than about 380, however, no two-dimensional solutions are stable. Comparisons with previous theoretical and experimental work are given. (Author)

Descriptors :   *Two dimensional flow, *Convection(Heat transfer), *Porous materials, Partial differential equations, Equations of motion, Numerical analysis

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE