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Metal foams have gained attention due to their heat transfer augmenting capabilities. In the literature, correlations describing relations among their morphological characteristics have successfully been established and well discussed. However, collective expressions that categorize stacked wire mesh based on their morphology and thermo-hydraulic expressions required for numerical modeling are less explored in the literature. In the present study, cross relations among the morphological characteristics of stacked wire-mesh were arrived at based on mesh-size, wire diameter and stacking type, which are essential for describing the medium and determining key input parameters required for numerical modeling. Furthermore, correlation for specific surface area, a vital parameter that plays a major role in interstitial heat transfer, is provided. With the arrived correlations, properties of stacked wire-mesh samples of orderly varied mesh-size and porosity are obtained for various stacking scenarios, and corresponding thermo-hydraulic parameters appearing in the governing equations are evaluated. A vertical channel housing the categorized wire-mesh porous media is numerically modeled to analyze thermal and flow characteristics of such a medium. The proposed correlations can be used in confidence to evaluate thermo-hydraulic parameters appearing in governing equations in order to numerically model various samples of stacked wire-mesh types of porous media in a variety of heat transfer applications.

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The paper focuses on optimizing hybrid PCM filled heat sinks with a multi-objective approach. In the current study, the fins are oriented both horizontally at the sidewalls and vertically at the bottom side in the enclosure. Two heat sinks with different types of fin shapes are introduced in the enclosure. A rectangular shape finned heat sink, and a tapered shape finned heat sink is incorporated in both sidewalls and bottom walls. The study’s main goal is to optimize the PCM-based heat sink to prolong the charging cycle (melting) and shorten the discharging cycle (solidification). The PCM used in the study is n-eicosane, and the material for the heat sink is aluminum. A heat flux with constant supply of 2000 W/m2 is provided at the enclosure bottom, and the remaining walls are insulated. A 2-D numerical simulation is done using the commercial software ANSYS Fluent. The multi-objective optimization is carried out using the technique for order preference by similarity to ideal solution (TOPSIS) optimization technique. For a constant PCM volume for both the cases, fin spacing, fin positioning, and fin heights are varied. The output results determined the optimum configuration for the stretched melting period and minimized solidification period.