风扇结构和肋高对芯片散热器散热性能的影响

采用热阻分析法和CFD软件Fluent数值模拟相结合,研究风扇结构即风扇通风直径或外壳厚度以及肋片高度对芯片散热器散热能力的影响。结果表明,较小的通风直径导致肋片散热能力下降的根本原因为回流区面积的增加和空气流量的减小。此外,肋高的改变直接导致了流道几何参数的改变,进而对表面对流传热系数产生了重大的影响。     

一种机载相控阵天线散热器的优化设计方法

机载相控阵天线体积小、重量轻，但因其具有工作时间长、发热量大等特点而使天线内部热流密度较高，从而影响了天线的使用寿命和可靠性，因此须合理配置散热器以进行辅助散热。以某机载相控阵天线为研究对象，通过建立散热器热阻与大功率器件总发热量间的数学模型，获得影响散热的关键几何参数，然后采用ANSYS Icepak构建热仿真模型，以散热器热阻最小为优化目标函数，对强迫风冷条件下的散热器进行设计和优化。仿真结果表明：该方法理论计算量少，工程实施便利，对机载相控阵天线散热器的合理配置具有较高的工程实践价值。     

车载主机箱CPU散热器结构设计及温度场分析

首先,经相关理论计算确定了散热器的肋间距为5 mm,肋高为15 mm;然后,利用自建实验台对散热器在3种不同功率、不同风速下的散热过程进行对比实验分析,说明了散热器在高功率情况下散热状况受气体流速影响较大;最后运用Workbench仿真软件对不同肋厚的散热器结构进行热分析,得到了在风冷对流工况下,肋厚为1.5 mm,风速为1.0 m/s时散热器的散热性能最佳,且满足了散热设计要求。     

基于遗传算法的散热器翅片优化设计

为了设计工程约束下的高性能散热器,基于散热器热阻网络模型,建立了散热器优化目标函数,利用遗传算法对目标函数进行优化,获取了工程条件约束下散热性能最优的散热器几何参数。计算结果与商用软件仿真结果符合较好,表明文中所建模型的准确性和有效性。文中的研究为提高高性能散热器的设计能力及新产品的研发效率提供了有益参考。     

某高功率密度密闭电源的结构热设计

分析了某高功率密度密闭电源的散热途径,提出利用矩形肋片的壳体扩展表面结构来加强散热的设计方法。应用热计算分析软件Flotherm,建立了该电源的热仿真模型,将提取的对扩展表面积作用明显的肋片高度、厚度和数量作为热优化设计的输入变量,展开了热优化计算。实践表明,优化后的电源结构能很好地满足散热要求。     

CPU散热器结构设计与热分析

CPU散热器是将CPU核心热量迅速导出的关键,已成为获得新一代电子芯片的主要问题之一。采用数值模拟方法对放射状太阳花CPU散热器进行三维流场及温度场分析,探讨放射状散热器在不同的肋片形状、肋片数N和肋片厚度等各种不同的参数作用下,对于整体散热器散热和流动性能的变化与影响,同时分析了太阳花散热器自然对流和瞬时动态特性。     

基于ICEPAK的EPS控制器的散热优化研究

针对EPS控制器中MOSFET管过热而造成控制器失效的问题,对EPS控制器的散热性能进行了分析。基于传热学理论,计算MOSFET的功率损耗并系统分析了控制器的散热路径,初步选择了散热器的参数并利用三维设计软件建立了控制器的仿真模型,运用热分析软件ICEPAK对控制器的仿真模型进行了数值模拟,得到了控制器稳态工作条件下的温度场。同时结合影响散热器散热性能的因素,分别以散热器热阻、质量和MOSFET温度为优化目标对散热器结构参数进行了优化。最后利用高低温交变试验箱和温度传感器,对控制器在高温、负载下的散热器底板温度进行了测量并记录试验数据。实验结果表明,控制器温度场的仿真是准确的,两者最大误差在15%以内,证明优化后的散热器结构是合理的,同时也验证了模拟仿真对控制器散热设计的可行性和有效性。     

型材散热器的优化设计

本文针对散热器在强迫风冷条件下的散热性能优化问题进行了分析研究.对于所采用的优化方案的热分析模型作了描述.分析了绕流对散热器性能的影响,并根据一种较为简便的数学模型,用迭代的方法确定出肋片上的实际流速.最后给出了采用这些模型计算出的在不同工作环境下型材散热器的优化尺寸.     

车辆散热器冷热侧耦合散热的数值模拟研究

为缩短发动机冷却系统散热性能匹配设计开发周期,介绍了一种快捷、可靠地计算散热器性能参数的数值模拟方法。通过对散热器进行换热风洞试验研究,分析其在一定水流量条件下,换热功率、出水温度与迎面风速的关系。然后根据原始几何参数建立了散热器计算域物理模型,分别采用多孔介质模型和双流换热器模型表征散热器芯体翅片结构和热交换模型,采用CFD数值模拟方法对散热器冷、热侧耦合散热进行仿真分析,得到散热器换热功率和出水温度分析数据,并与试验数据进行对比,误差在以内,验证了此模拟计算方法的可靠性。     

基于ANSYS的空调散热器结构对其散热性能的影响分析

空调散热器的散热性能是影响空调工作性能的重要因素,如何合理设计散热器结构以提高空调散热性能是目前亟待解决的问题。现利用ANSYS软件建立了散热器的有限元模型,并对其进行了热学性能分析,研究了散热性能与散热器结构的关系,然后对结果进行了对比分析,得到了散热器温度分布云图、相同结构不同鳍片数对散热器散热性能影响的关系曲线图以及不同结构相同鳍片数对散热器散热性能影响的关系曲线图,为空调散热器的优化设计提供了重要的依据。     

基于ICEPAK仿真的散热器结构热设计研究

文中利用ICEPAK软件对多密度高功率芯片散热器结构进行了热设计研究。研究确立了影响翅片散热器散热性能的关键尺寸设计参数,如基板厚度、翅片高度、翅片厚度和翅片间距等,并得出了各尺寸设计参数对其散热效果的影响趋势,确定了散热器结构的最佳布局方案。此外,研究还建立了最佳布局的散热器结构实物并进行了高低温试验以模拟其高温散热情况。通过实验数据对比发现,仿真计算结果与实际较为吻合,进而验证了ICEPAK软件在电子设备散热设计方面的准确性与可靠性。     

Modeling and simulation of a parallel plate heat sink using computational fluid dynamics

Desktop computers have changed to accommodate increasing power, approaching 100 W. Heat dissipation becomes a significant issue in efficiency promotion and stable operation of air-cooled microelectronics and power electronics components and assemblies. Finned heat sinks are commonly used devices for enhancing heat transfer from air-cooled microelectronics and power electronics components and assemblies. The use of finned heat sinks increases the effective surface area for convective heat transfer, reducing the thermal resistance and operating temperatures in air-cooled electronics. The task of selecting the best heat sink for a particular application from the hundreds of configurations available from the various manufacturers can be a formidable task for an engineer. In a typical heat sink design, the objective is to achieve target heat dissipation, while restricting the consumption of valuable resources such as mass, fan power, pressure drop, and space claim. In this research work, preliminary studies have been carried out for the performance improvement of a parallel-plate heat sink considering the various geometric parameters, such as number of fins, fin length, fin height, and base height. The modeling and simulation of the heat sink is carried out with the computational fluid dynamics package. The results are analyzed using analysis of variance and response graphs.     

大容量电力电子装置中板式水冷散热器的优化设计

为提高水冷散热器的散热能力、控制其温度均匀性,在散热器外形尺寸及流量一定的条件下,从理论上对层流范围内平板式水冷散热器的三个通道参数(通道数、散热片高度、散热片占空比)与散热器量纲一散热热阻的变化关系进行了推导。提出可根据这些变化关系来对任意尺寸平板式水冷散热器的各通道参数进行优化选择,在工程设计上具有很好的指导意义,仿真和试验结果证明了方法的有效性并表明:小通道尺寸的平板式水冷散热器对于解决大热流密度器件的散热更为有效,散热效率更高;在同样的参数情况下,流量增大则散热器效率降低,应综合考虑散热器流阻和流体平均温升的控制要求来选择流量。     

Geometry optimization of a cylindrical fin heat sink using mine blast algorithm

The heat sinks are utilized in electronic devices to eliminate heat from the chip and efficiently transmit it to the environment. Therefore, the optimal geometry sizes of fin heat sinks are the point of concern for manufacturers and designers. For this reason, the importance of optimization techniques particularly metaheuristics is understood. The design variables are width of heat sink, number of fins, fin height, and fin diameter. The various responses that have been considered are electromagnetic emitted radiations, thermal resistance, and mass of the heat sink investigated separately and simultaneously (multi-objective). Mine blast algorithm (MBA), as a recently developed optimizer, is inspired from explosion of mines. The optimum dimensions and values for each response have been obtained by the MBA and have been compared with other optimization methods in the literature. In terms of thermal resistance and mass responses, the MBA has offered better values, while for the emitted radiations, the obtained results obtained by Taguchi-based gray relational analysis (TGRA) was preferred. For manufacturing point of view, the MBA and TGRA both suggested better and efficient design. In addition, the value path analysis has been carried out to compare the trade-off among the considered responses. Finally, parametric sensitivity analyses have been implemented for design parameters, and discussions and comparisons have been carried out for the effects of each decision variable. By considering all responses, width of heat sink and fin height are considered as the most important and effective design parameters, respectively.     

Experimental and CFD analysis of heat sinks with base plate for CPU cooling

Experimental and theoretical investigations of the thermal performance of a variety of heat sinks have been made. The heat sinks investigated were: straight finned, elliptical finned, small pin finned, circular disc finned, elliptical disc finned, frustum finned and double base straight finned. Realistic, manufacturable geometries are considered for minimizing thermal resistance at low velocity. The experimental results of several of the simple geometry heat sinks have been compared to those predicted by a commercially available computational fluid dynamics code fluent. The parameters such as fin geometry, fin pitch and fin height are optimized primarily in this paper and a second task is carried out to optimize base plate thicknesses, base plate materials and modify design of heat sink for improving the thermal performance in the next generation. Although the performance of heat sink is good, the temperature of heat sink at center is high. In this research work, the best heat sink geometry is selected and modified in order to reduce maximum temperature distribution and hot spots of heat sink at center by changing the geometry design and adding one more base. It is observed that flow obstructions in the chassis and the resulting air recirculation affect the heat sink temperature distribution.     

平直翅片热管散热器的正交数值模拟优化

文中以平直翅片热管散热器为研究对象,研究了翅片厚度、翅片间距、翅片高度、翅片宽度和热管直径 5 个结构参数对翅片换热性能和阻力特性的影响,采用正交实验设计的方法设计了上述结构参数的 15 个组合方案,利用 CFD 数值模拟的方法对每个组合方案下翅片的流动换热性能进行了模拟。以努塞尔数 Nu 、阻力系数f、传热性能综合评价指标(Performance Evaluation Criteria, PEC)作为评价指标,在每个评价指标下利用极差分析挑选出性能最优的组合方案。 该方法能快速获得散热器结构的优化方案,并分析出主要影响因素,对工程应用有一定的指导意义。 结果表明:影响 Nu 和 f 的最主要因素是热管直径,影响 PEC 的最主要因素是翅片厚度。 对于本文研究的散热器,其最优参数组合方案为:翅片厚度为 0. 6 mm,翅片间距为 2. 2 mm,热管直径为 6 mm,翅片高度为 65 mm,翅片宽度为 28 mm。     

大功率固态功率管热设计优化及验证

为研究大功率固态功率管的传热问题,文中以某风冷固态功率管为例,介绍了其结构形式,分析了从功率管管壳到空气热沉之间的主要热阻,通过热设计软件进行了仿真计算。计算结果表明,造成功率管温升较大的热阻有对流换热热阻、导热热阻和接触热阻。为了降低功率管的结温,对每个热阻分别进行了优化设计和计算,通过试验对优化后的模型进行了验证,测试结果与仿真结果一致。最后还对大功率固态功率管的热设计优化方法进行了介绍。