Convective heat transfer for viscous fluid flow through a metallic packed bed

A numerical-experimental methodology is presented to determine the interstitial heat transfer coefficients in the oil flow through a metallic packed bed where the fluid is not in thermal balance with the solid phase. The heat transfer coefficients are obtained through the Single Blow Transient Method, combining the experimental results in a test equipment with the numerical solutions of the proposed mathematical model. The system of partial differential equations generated in the mathematical model is solved through a numerical methodology based on the finite volume method. This numerical model was constructed in the software of Computational Fluid Dynamics CFX 4.3 (TM) and was developed in cylindrical coordinates, using a scheme of central differences to approximate the diffusive terms, a hybrid scheme for the convective terms and a totally implicit scheme to implement the transient state. The experimental tests and the numerical solutions were satisfactory for different values of superficial speed of the fluid at the entrance to the bed and for different porosity values, obtaining that the Nusselt numbers depend in great scale on the Reynolds numbers and the porosity of the media, agreeing with the results of similar investigations.