Effective surface modeling for momentum and heat transfer over rough surfaces: Application to a natural convection problem
Résumé
In this paper, we propose efficient and suitable effective surface models for steady laminar flows with heat transfer over rough surfaces. These models are developed in the frame of a domain decomposition method and consist in replacing the rough boundaries by effective smooth surfaces on which effective boundary conditions or wall laws are prescribed. The associated effective properties, namely the effective friction and heat transfer coefficients, are determined by the resolution of local closure problems over a representative pattern of the roughnesses. The impact of the flow parameters on these effective coefficients is analyzed, which allows to obtain useful estimates in some specific cases. Finally, two-dimensional numerical experiments are performed for a natural convection problem in a stamp shaped cavity to assess the validity of the proposed effective surface models. Throughout these tests, we also study numerically the impact of the position of the effective surface on momentum and heat transfers. © 2010 Elsevier Ltd. All rights reserved.
Mots clés
Closure problems
Effective boundary conditions
Effective property
Effective surface model
Flow parameters
Laminar natural convection
Natural convection problems
Numerical experiments
Rough boundary
Rough surfaces
Smooth surface
Surface modeling
Boundary conditions
Domain decomposition methods
Heat transfer
Knowledge based systems
Laminar flow
Natural convection
Surface measurement
Two dimensional