# Turbulent flow in porous medium

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 June 25, 2012, 11:40 Turbulent flow in porous medium #1 Senior Member   Join Date: Oct 2010 Location: Zurich Posts: 176 Rep Power: 15 Hi, I am solving a turbulent conjugate heat transfer problem in which water enters the domain at 11000 Re into a duct. After flowing some distance in the duct, it enters a porous medium and flows through it. Re inside the porous medium, based on true velocity and pore size is 600. I am using k-omega model to solve for turbulence. CFX uses the same model inside the porous medium also. I have questions regarding the same. 1. How are the momentum equations for porous medium modified for turbulent flow? CFX theory manual says that an effective viscosity is used in the momentum equation. Is this effective viscosity in the sum of laminar and eddy viscosity, as in normal Reynolds averaged momentum equation for fluid flow? 2. In case of the energy equation, the manual says that an effective thermal diffusivity is used. Is this effective thermal diffusivity the sum of effective thermal diffusivity for porous medium and the ratio meu_t/Pr_t (i.e. ratio of eddy viscosity and turbulent Prandtl number, similar to the Reynolds averaged energy equation for fluid flow) 3. what is 'H' in Eq. 1-259? Is it total enthalpy i.e. h+0.5*U*U? I am attaching the relevant excerpts from CFX manual for reference. Thanks for your inputs, Chander Last edited by Chander; June 25, 2012 at 21:02.

June 25, 2012, 21:15
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Excerpts from cfx manual
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 January 4, 2017, 04:55 #3 New Member   spz Join Date: Dec 2013 Posts: 12 Rep Power: 12 Hi Dear.. I am am starting my thesis which is similar to your problem. i want to know momentum and energy equation which fluent or CFX uses for turbulent flow in the porous region. would u please help me with this. i mean any references or..?

 January 4, 2017, 18:06 #4 Super Moderator   Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,623 Rep Power: 142 It is all described in the CFX and Fluent documentation. Have you looked in there?

 January 17, 2017, 10:50 #5 New Member   spz Join Date: Dec 2013 Posts: 12 Rep Power: 12 i have checked CFX and fluent but i couldn't find energy equation for porous media in turbulent regime