Heat dissipation has emerged as a critical challenge in server cooling due to the escalating number of servers within data centers. The potential of immersion jet technology to be applied in large-scale data center server operations remains unexplored. This paper introduces an innovative immersion jet liquid cooling system. The primary objective is to investigate the synergistic integration of immersion liquid cooling and jet cooling to enhance the heat dissipation capacity of server liquid cooling systems. By constructing a single-server liquid cooling test bench, this study compares the heat dissipation efficiencies of pure immersion and immersion jet liquid cooling systems and examines the impact of inlet water temperature, jet distance, and inlet water flow rate on system performance. The experimental outcomes show that the steady-state surface heat transfer coefficient of the immersion jet liquid cooling system is 2.6 times that of the pure immersion system, with increases of approximately 475.9 W/(m²·K) and 1745.0 W/(m²·K) upon adjustment of the jet distance and flow rate, respectively. Furthermore, the system model is streamlined through dimensional analysis, yielding a dimensionless relationship that encompasses parameters such as inlet water temperature, jet distance, and inlet water velocity. The correlation error is maintained below 18%, thereby enhancing the comprehension of the immersion jet cooling mechanism.

Microchannel liquid-cooled plates are widely used in high-performance electronic devices, but their heat transfer performance and pressure drop characteristics face complex challenges in the design process. In this paper, a counter-flow rectangular microchannel liquid-cooled plate is designed, and the effects of velocity, aspect ratio, and inlet/outlet forms on its heat transfer and pressure drop performance are investigated through orthogonal tests and numerical simulations. The results indicate that the velocity plays a crucial role in determining the plate’s performance. While increasing the velocity substantially enhances heat transfer efficiency, it also causes a steep rise in pressure drop. The aspect ratio has a lesser effect on the performance than the velocity, and smaller aspect ratios help to achieve a balance between thermal and flow properties. The comprehensive optimization of the inlet and outlet forms and velocity has a significant effect on the temperature uniformity and pressure drop, and the design of the cooling fluid inlet and outlet form of CM (side inlet and middle outlet) can effectively improve the temperature distribution and reduce the pressure drop at high velocity. The design parameters with the best overall performance are the aspect ratio of 2, the velocity of 0.5 m/s, and the CM inlet/outlet form (K2V0.5CM). Comparison with other design parameter sets verified that this parameter set showed significant advantages in cooling effect, temperature uniformity, flow and heat transfer performance. Finally, the correlation equation on Nu is established, and the simulated Nu as well as the calculated Nu are compared. In this thesis, a counter-flow rectangular microchannel cold plate is designed to optimize the flow rate, channel structure and other parameters through orthogonal tests to reduce the temperature gradient and balance the heat transfer and flow resistance to meet the demand for efficient heat dissipation of 350 W CPU. This study provides an important reference for the structural optimization of microchannel liquid-cooled panels and the engineering application of high-efficiency heat dissipation systems.

The parallel multi-branch pipeline system is usually used for fluid transportation and distribution in the cooling of high-power electronic equipment, especially in radar equipment. Using CFD software, a simulation study was conducted to analyze the fluid flow distribution and heat transfer characteristics within a 6 × 5 parallel multi-branch pipe. This study examined how the dimensions of the fluid channels in the liquid cooling system affected the uniformity of flow distribution and the cooling effectiveness of the system for electronic equipment. The deviation from the design flow rate was used as an evaluation criterion to assess flow distribution uniformity across the branches and components of the multi-branch liquid cooling system. After ensuring uniform flow distribution, the overall heat transfer characteristics of the liquid cooling system were analyzed. The main findings are as follows: by adjusting the flow channel dimensions within the system, the overall flow distribution uniformity increased by 10%, with the deviation from the design flow rate in each T/R component remaining within 20%. The 6 × 5 parallel multi-branch cold plate efficiently cools T/R components with heat flux densities of up to 500 W/cm², maintaining the maximum component temperature below 358 K.