Improving Geometry of Microchannel Heat Sinks by Adding Fins to Walls of Microchannels

The dissipation of heat generated in electronic and industrial chips is essential for the safe operation of these components. For this purpose, one of the best choices is a microchannel heat sink, which offers a lower pressure drop compared to other channels while maintaining a high heat transfer rate. In this study, a fractal microchannel heat sink, introduced in recent years, has been numerically investigated. To enhance the performance of the microchannel, two types of fins have been added to the microchannel walls, resulting in the creation of two new geometries. In the first new geometry, fins are placed at the bottom of the microchannel, while in the second one, fins are placed on the sidewalls of the microchannel. It is worth mentioning that the volume of fins used is consistent across both geometries. Thermal and hydraulic parameters have been examined, revealing that both new geometries, the Nusselt number increased, with the highest value of 28%. observed in the microchannel with fins on the sidewalls. Additionally, both geometries the pumping power increased by 120% with the microchannel fins at the bottom. Finally, by evaluating the performance coefficient, it was determined that the microchannel with fins on the sidewalls increased the overall performance by 3 to 6% across different flow rates, whereas the microchannel with fins at the bottom reduced the system's performance by 7%. Therefore, for efficient dissipation of the generated heat, it is preferable to use a microchannel heat sink with fins on the sidewalls.