Influence of Thickness of the Porous Layer on Thin Film Condensation in Forced Convection in a Canal Whose Walls are Covered with a Porous Material: Determination of Lengths of Entry
Pape Tamsir Ndiaye
*
Fluid Mechanics and Transfer Laboratory, Physics Department, Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal.
Momath Ndiaye
Fluid Mechanics and Transfer Laboratory, Physics Department, Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal and Department of the Ufr Hydraulics, Rural Engineering, Machinery and Renewable Energy, University of Sine Saloum Elhadji Ibrahima NIASS, Kaolack, Senegal.
Goumbo Ndiaye
The Water, Energy, Environment and Industrial Processes Laboratory of the Polytech Higher School, Cheikh Anta Diop University, Dakar, Senegal.
Omar Ngor Thiam
Fluid Mechanics and Transfer Laboratory, Physics Department, Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal and Research Group on Solar Energy and Transfers (GREST), Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal.
Mamadou Lamine Sow
Fluid Mechanics and Transfer Laboratory, Physics Department, Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal and Research Group on Solar Energy and Transfers (GREST), Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal.
Cheikh Mbow
Fluid Mechanics and Transfer Laboratory, Physics Department, Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal and Research Group on Solar Energy and Transfers (GREST), Sciences and Technologies Faculty, Cheikh Anta DIOP University, Dakar-Fann, Senegal.
*Author to whom correspondence should be addressed.
Abstract
We have examined film condensation in a channel whose walls are covered with porous media numerically. The transfers in the porous medium and the liquid film are respectively described by the Darcy-Brinkman-Forchheimer model and the equations of the hydrodynamic and thermal boundary layers and are solved by the decentered implicit finite difference method and the iterative Gauss-Seidel method.
After validating, the influence of the thickness of the porous layer on the longitudinal velocity and the temperature profiles in both media (pure liquid and porous medium), the thickness of the liquid film, the local Nusselt number and the lengths of entry have been studied.
We note that an increase in the thickness of the porous layer increases the friction and decreases the contact of the fluid with the cold plate and allows a decrease in the longitudinal velocity and an increase in the temperatures in the porous medium and the pure liquid, a decrease liquid film thickness (disadvantaged condensation) and increases the local Nusselt number and also an increase in the length of entry. The increase in length of entry is quasi-linear. The sensitivity of condensation to a change in thickness of the porous layer is constant.
Keywords: Channel with porous wall, condensation thin film, generalized Darcy-Brinkman- Forchheimer model, lengths of entry, thickness of the porous layer