dc.description.abstract | In recent years, electronic components are developing rapidly, and their efficacy is becoming more and more sophisticated while pursuing the product orientation of shrinking, light, thin, and short. The decrease in mass and volume and the increase in power per unit density bring heat concentration. The accumulated heat causes key components to overheat, failing and damaging the components and affecting the life span. Due to the limitation of heat dissipation space and area, research on high-density thermal energy transport technology has become essential. To ensure the product life cycle and functional stability, mastering the heat transfer path to perform heat flow analysis, with the guideline of designing a practice suitable for research and development, testing, assembly, and production cannot be overlooked. It is also vital to adopt a standard process to build a model and use experimental data to verify the reliability of the model. Based on the model, one can propose a design optimization plan, formulate improvement goals for product functional characteristics and usage scenarios, and expect to improve the overall heat dissipation performance and ease of production.
In this study, the computational fluid dynamics method is used to simulate the conjugate heat transfer using the COMSOL simulation software. The four modules composed of identical casings are the main structure and heat transfer path. The internal core heat source in each module directly contacts and transfers heat to the cold plate from top to bottom through the casing body. The cold plate is filled with pure water as the working fluid for water-cooled internal circulation as a heat dissipation solution. Therefore, the design of the internal flow channel of the cold plate becomes a critical controlling factor that affects the heat source temperature.
The flow field in the cold plate is judged to be turbulent by calculating the Reynolds number. Considering the high-gradient flow field of the viscous boundary layer that cannot be ignored, SST(shear stress transport) model is selected as the turbulent flow model in this study. By refining the grids size and retaining the y plus as small across the boundary, the flow velocity gradient is resolved in the boundary layer. The model is moderately adjusted to maintain the grid quality while improving the numerical convergence. The grid independence test is performed. The temperature of the heat source and the average velocity are adopted as the characteristics of the simulation experiment to shorten the simulation analysis time cost.
In addition, we apply the contact thermal resistance at each interface of the model defined according to the experimental test data. The mesh of each heat source is moderately replaced by the thermal resistance, which saves computational time without reducing the resulting
authenticity, which conforms to the experiment. We use the model as the foundation for optimizing the effectiveness of the cold plate, testing various flow channel designs, and adjusting the flow direction and geometry by analyzing the heat source′s position. In addition, multiple types of vortex generators are tested to generate flow disturbance, which helps the boundary layer mixing effect between heat transfer paths. We study the temperature change of the heat source and discuss the pressure drop and the manufacturing process to evaluate the performance and explore the feasibility of developing advanced configurations. | en_US |