Offset Temperature and Amplitude–Frequency Effect on Convection Heat Transfer in Partially Gradient Porous Cavity with Different Outlet Port Locations

Based on admirable porous media performance and the popularity of additive manufacturing technology, gradient porous media are progressively being applied in increasing fields. In this study, convection heat transfer within a square vented cavity, partially occupied by two copper metal foam layers of 10 and 20 PPI saturated with nanofluid, was assessed numerically. The left wall was heated uniformly and non-uniformly by applying multi-frequency spatial heating following a sinusoidal function. Governing equations, including continuity, the Darcy&ndash:Brinkmann&ndash:Forchheimer model, and local thermal non-equilibrium energy equations, were adopted and solved by employing the finite volume method. The influences of relevant parameters, including nanoparticle concentrations 0%&le:&phi:&le:10%, Reynolds number (1&le:Re&le:100), inlet and outlet port aspect ratios 0.1&le:D/H&le:0.4, three outlet vent opening locations (So=0 left, (So=H/2&minus:D/2) middle, and (So=H&minus:D) right), sinusoidal offset temperature (&theta:o=0.5, 1), frequency (f=1,&nbsp:3,&nbsp:5), and amplitude (A=0&minus:1), were examined. The results demonstrate that flow and heat transfer fields are impacted mainly by these parameters. Streamlines are more intensified at the upper-left corner when the outlet opening vent is shifted towards the right-corner upper wall. Fluid- and solid-phase Nusselt number increases Re, D/H, &theta:o, A, and f are raised, specifically when A&ge:0.3. The Nusselt number remains constant when the frequency is raised from 3 to 5, definitely when D/H&ge:0.25. In uniform and non-uniform heating cases, the Nusselt number of both phases remains constant as the outlet port is shifted right for Re&le:10 and slightly for higher Re as the outlet vent location is translated from left to right.