화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.49, No.21-22, 4095-4105, 2006
The effective thermal conductivity of wire screen
A combined experimental and theoretical investigation was conducted to examine the thermal conductivity of layers of wire mesh screen. Employing a carefully controlled sintering process, layers of sintered wire screen were examined experimentally. The experimental results indicate that the effective thermal conductivity in the z-direction (i.e., normal to the plane of the wire screen layers) for single layer, inline structures and staggered multilayer wire screens is approximately 4-25% and 6.4-35% times that of the solid metal thermal conductivity, respectively. In addition to the conductivity of the base material, the contact conditions between the individual wires, as well as between the individual layers were found to be the most important factors in the determination of the effective thermal conductivity. In parallel with the experimental investigation, an analytical model was developed and shown to accurately predict the effective thermal conductivity of these layers as a function of the contact conditions between the wires, between the individual layers, and between the solid heating surface and the first layer of screen. In addition to the contact conditions, this new model is strongly dependent on three geometric parameters: the mesh number, M, the wire diameter, d, and the compression factor, cf. Experimental data from this and other investigations were used to verify the accuracy of the model, which was shown to accurately predict the effective conductivity as a function of the above mentioned parameters. In addition, a comprehensive literature review was performed and analyzed in order to further substantiate the validity and accuracy of this new model. The resulting conclusions highlight the importance of the contact conditions between the wires in the individual layers, and between the layers and the solid surface. (c) 2006 Elsevier Ltd. All rights reserved.