Theoretical Investigation And Structural Optimization Of The Laminar Flow And Heat Transfer Characteristic In Triangular Micro-Channels

In recent years, with the rapid development of science and technology towards miniaturization, integration and intelligence, microelectronic systems (MEMS) develop rapidly and varieties of microelectronic products progress towards small size, light weight, integrated direction, which lead to the electronic product heat dissipation problem is more and more prominent. Because the temperature and the temperature distribution impact significant on the electronic product, the traditional cooling methods and cooler cannot meet the demand of chip in the electronic equipment heat dissipation as far. As a new cooler,micro-channel heat technology is widely used in the fields of machinery, defense, medical and biological engineering, aerospace, chemical analysis and so on. And the micro-channel heat sink have compact structure, high heat transfer efficiency, light weight, safe and reliable, small temperature difference and other conventional devices do not have the traditional advantages, which making the micro-channel heat sink developing rapidly in research and applications, many scholars have proposed many issues about the flow and the heat transfer process within the micro-channel, considering the production and processing easy to clean. Currently, most of the micro-channel cross section is circular and rectangular. As the limitations of some space, so we have to use the micro-channel which it’s cross section is triangular or other shaped.In this paper, assuming that the working fluid is ideal, fixed the physical properties, incompressible fluid, under conditions of steady laminar flow study the convection and heat transfer in the fully developed section of isosceles triangle cross section micro-channel. First, based on the traditional fluid mechanics and heat transfer fluid in pipe, select a unit in isosceles triangle cross section micro-channel, analysis its conservation of momentum and energy conservation, get momentum equation and energy differential equation. solving differential equations depending on the boundary conditions to get the analytical solution of the velocity distribution and temperature distribution in isosceles triangle cross section micro-channel, then derived the expression of Nusselt number and Poiseuille number which can represent the fluid flow and heat transfer performance in the fully developed section of isosceles triangle cross section micro-channel. and numerical simulation to verify the correctness of the results.Secondly, based on the results derived before, take a smaller drop and micro-channel heat sink thermal resistance in isosceles triangle under specific constraints as goal, take the size of the micro-channel structure variables as design variables, use the multi-objective genetic algorithm NSGA-Ⅱ (non-dominated sorting genetic algorithm multi-objective optimization) program to optimize. Finally, numerical simulation the fluid flow and heat transfer in optimized micro-channels use finite element software, and analyze the thermal performance.