Heat Dissipation and Thermal Stress-Strain Characteristics of an Impinging Jet Strengthened Rib Surface under a Laser Heat Source

To reduce the maximum temperature and improve the temperature uniformity of a laser heating surface, a comprehensive heat dissipation method for jet impingement strengthening of the surface is proposed. In this study, a performance evaluation factor (PEC) that considers both heat dissipation and flow resistance characteristics was introduced for numerical research and compared with traditional microchannel heat dissipation characteristics. Results show that reducing the impact distance causes the boundary layer in the impact zone to become thinner, increases the transverse flow velocity, and moves the vortex center to the central entrance, thereby improving the heat transfer efficiency. The reduced impact distance not only reduces the maximum temperature of the system, it also achieves temperature uniformity. A comparison with traditional microchannel heat dissipation characteristics reveals that the PEC reaches its maximum at a dimensionless jet impingement distance of 0. 25, making this system suitable for heat dissipation of laser heat sources. In addition, the results of thermal stress and strain analysis indicate that under the yield limit of the same material, the highest laser heat flux density that the system can withstand is significantly greater than that of the microchannel cooling system, resulting in better heat transfer performance and greater applicability.