Comprehensive investigation of optimal vortex generator shape and position for heat transfer enhancement in a rectangular passage to cool electronic appliances: A numerical analysis

Poor thermal management can cause overheating that can drastically reduce any electronic equipment's performance and its life. This study discusses an effective heat dissipation technique by geometrical modifications to resolve the overheating issue of electronic equipment's, specifically by utilizing vortex generators to enhance heat transfer. In this work, hot blocks were placed in a channel as an equivalent to electronic chips that may fail due to overheating. Vortex generators (VG) were deliberately placed inside the channel at different spots with an aim of improving heat transfer. The finest profile of the VG with its influence and optimum position on the Nusselt number is obtained for different quantities of the Reynolds number. A laminar, two-dimensional, and steady-state fluid flow with mixed convection heat transfer exists inside the channel. Three shapes of VG (triangular, square, and circular) have been selected and installed at different places. The investigation is performed for a value of Reynolds numbers (250, 500, and 750) considering the laminar zone at the beginning of the channel keeping the same flow situations. An appreciable increase in the Nusselt number can be seen in all cases on account of the installation of a VG. However, the improvement in Nusselt number is found to be 8.72% and 4.69% more in the case of the square VG as compared to triangular and circular shapes respectively for the lowest value of Reynolds number. For the moderate value, the square VG gains an increase in Nusselt number equal to 1.04% and 4.99% as compared to triangular and circular VG respectively. It is also found that under a high value of Reynolds number (high fluid velocity), the performance of triangular VG is better which has 2.60% and 8.08% more value of Nusselt number as compared to square and circular VG respectively. The analysis has been carried out using ANSYS 16.0 by a Semi-Implicit Method for Pressure-linked Linked Equations (SIMPLE). After careful consideration and analysis, it is recommended to use a square vortex generator for lower to medium Reynolds numbers, while a triangular shape is more appropriate for higher Reynolds numbers. This study lays the groundwork for further design optimization of VGs, integrating advanced cooling techniques and exploring novel materials, that can eventually reduce the overheating issues to a greater extent in electronic devices as small as mobile phones and laptops to as large as HPCs.