【作者】 李艳红；

【导师】 叶恒棣； 刘吉普；

【作者基本信息】 湘潭大学 ， 化工过程机械， 2010， 硕士

【摘要】 目前,随着电子技术的快速发展,计算机的运用越来越普及,大家的日常生活和工作与计算机联系得越来越紧密,同时大家也对计算机的稳定性、实用性、集成性等方面提出了更高的要求。这使得CPU芯片的集成度不断地提高,单个芯片的功率也在不断增加,发热量惊人上升。CPU的工作温度直接关系到计算机的稳定性和使用寿命。温度升高会使计算机运行速度下降,有时会使计算机出现死机甚至芯片烧毁等,解决CPU散热问题非常迫切。而采用高效散热性能的CPU散热器是降低CPU温度的有效途径之一。本文对目前市场上的一款特殊的放射状翅片CPU热柱散热器作为研究对象,对该散热器进行实验研究和流场及温度场的数值模拟,分析其综合散热性能。同时,为以后CPU散热器的热设计提供参考。本文首先对热柱的工作原理及特点进行了分析,讨论了热柱散热器相对于传统实体铜柱散热器散热方式所存在的优势。并推导出热柱散热器的总传热模型,找出了影响散热的关键因素。同时,搭建了实验测试装置,对热柱散热器进行了测试实验,研究其在不同工况下散热器的散热性能。得到了热柱的整体温度分布图以及散热器在不同风速、不同加热功率下的散热性能曲线,总结出功率和风速的改变对发热芯片表面温度的影响。运用FLUENT软件,对不同工况下的散热器进行了流场及温度场的模拟分析,得到散热器流场及温度场的具体分布情况。并将模拟所得结果与实验所得结果进行比较分析,以此验证了实验测试装置的可行性和FLUENT软件在CPU散热器热设计中的可靠性。结果表明,与同等尺寸下的铜柱散热器相比较,在相同工况条件下,热柱散热器能带走更多的热量,使CPU的表面温度降的更低,并且对CPU热源具有良好的均热效果。热柱散热器不仅能将热量更快地传到整个散热器,而且将热量更均匀地分布在较大散热面积上,充分发挥每个翅片的散热作用,使散热器在冷却气流较小的情况下,也可以较好地满足CPU芯片的散热需求,可以有效解决风扇高转速带来的噪音问题。更多还原

【Abstract】 With the rapid development of electronic technology, the use of computer is becoming more popular now, everyone’s daily life and work increasingly closely linked with the computer, while set higher requirements on the computer’s stability, usability, integration and other aspects, This makes the integration of CPU chip improve constantly,a single chip power is also increasing, heat is in alarming rise . CPU’s operating temperature is directly related to the computer’s stability and service life. High temperature will speed the computer down and sometimes the computer will crash or chip burning, etc. It is very urgent to solve the CPU heat problem. It is one effective way to use of the high performance CPU cooling radiator to reduce the CPU temperature.This article studied a unique radial thermal column radiator, which has already used in the market. In order to analysis of the heat dissipation, we make experimental studies on the radiator and simulation on the flow field and temperature field. Meanwhile, this proposes valuable advice for CPU radiator thermal design.Firstly, the working principle and characteristics of the thermal column were analyzed,compared to conventional solid copper pillar radiator,thermal column radiator has the existence of advantages. And we derive the total thermal column radiator heat transfer model; find the key factors affecting the heat transfer. At the same time, the experimental device is manufactured which is used to test thermal column radiator and study its performance under different operating conditions. According to the results of tests, the whole plume temperature distribution and the cooling performance curve of radiator at different wind speeds and different power were obtained, the change of power and speed influence the surface temperature of hot chips were summarized.FLUENT software is used to simulate the flow field and temperature field of the radiator on different conditions. The radiator flow and temperature distribution and the details of flow and heat transfer were obtained. And simulation results are compared with experimental results to verify the feasibility of the experimental apparatus and the reliability of FLUENT software in the CPU heat sink thermal design. The results show that compared with the same size copper pillar radiator, the thermal column radiator can drop the temperature of CPU lower, and has a good soaking effect on the CPU heat source. The thermal column radiator not only can spread the heat throughout the radiator more quickly, and the heat is distributed in a larger area more evenly, which play the role of each of the cooling fins fully. So this radiator can satisfy the cooling needs of CPU chips at low wind speed, and also solve the noise problems effectively which high speed fan bring.更多还原