基于ICEPAK的液冷冷板散热结构的优化设计

以某雷达T/R组件的液冷散热为研究对象,通过分析比较仿真结果,对原冷板流道结构进行优化,在流道内分别增加方柱型和圆柱型两种散热齿。利用实验对这两种方案进行验证,实验与仿真结果的误差小于2%。结果表明：散热齿的引入显著改善了冷板的散热效果,方柱型散热齿的散热效果更优于圆柱型。优化后的两种流道方案均能满足此次冷板热设计要求。综合分析,最终选择圆柱型散热齿的流道结构,方柱型散热齿可以应用于热流密度更高的电子设备热设计中。     

一种相控阵天线强迫风冷热设计方法

阵面温度控制是相控阵天线结构设计的关键技术之一。文中针对某相控阵天线的热设计要求,设计了一种用于相控阵天线散热的强迫风冷系统,并采用数值分析方法,对该系统作用下的相控阵天线阵面热性能进行了分析。对不同流道参数、散热器参数和冷却气体流速下的阵面温度和流体压力进行了仿真。仿真结果表明：冷却气体温度和速度对散热效果影响显著,增加散热片的肋片数量和高度能够提高散热性能。以仿真结果为依据,对相控阵天线的结构参数进行了优选。进行了对比实验,验证了仿真计算的有效性。     

封闭机箱冷却流场的热优化设计

机箱的散热能力不仅会影响计算机的计算速度,也会影响各元器件的使用寿命。为了提高计算机封闭机箱的散热能力,依据湍流理论,建立了机箱冷却流场数学模型,并采用Icepak电子热设计专用软件对排风和进风方式进行了仿真优化。通过分析比较封闭机箱内电子元器件的温度、热流速度曲线、风流动轨迹图,获得了较为理想的温度场的冷却方式。优化结果表明,该优化方案实用、简单、准确,机箱散热效果好,为电子产品热设计提供了一个较为理想的热分析方法。     

电动汽车锂离子电池组散热优化设计

针对电动汽车锂离子电池组散热不均匀会影响电池组使用性能、可靠性和安全性的问题,对电池组散热方案进行优化设计.描述锂离子电池的产热模型,建立锂离子电池组三维模型,介绍计算流体力学（Computational Fluid Dynamics,CFD）计算涉及到的固体热传导和流体热传导控制方程;通过进风口角度的选择、进风口流速的选择、鼓风冷却和抽风冷却的对比以及锂离子电池局部倒角的选择确定几种散热方案,使用FLUENT进行数值仿真并得出各方案的总体流场特性、局部流速和温度分布情况.通过对各散热方案的对比和评估,发现当进风角度达到3°时,温度最高点和均匀性有明显改善;在一定的速度范围内,提高进风口流速可以很好地改善系统的散热效果,但是当进风口流速超过某一范围（30 m/s）时,散热效果递增不明显;对于相同的散热结构,鼓风冷却效果明显优于抽风冷却效果;通过电池组局部倒角等局部微小结构可以实现温度场优化.     

基于知识的塑料异型材挤出模内筋流道CAD系统

内筋将型材截面分隔成封闭的多型腔结构，以增加型材的强度，同时也增加了挤出模设计难度．为了指导挤出模的设计，提出了口模内筋间隙和内筋流道平直段长度的设计原则以及内筋供料方式的智能选择．在此基础上，在SolidWorks2000平台上开发了一个基于知识的、具有型材截面尺寸自动识别功能的内筋流道CAD系统。     

基于IGBT的功率变换器散热设计与研究

本文对IGBT功率变换器设计中强制风冷散热方式进行了研究。应用ICEPAK软件搭建系统热仿真模型,并对散热器结构参数和风量进行仿真分析与优化设计。在此基础上,试制一套强迫风冷散热系统,通过对计算和仿真结果与试验测试结果的对比,验证了散热系统热阻计算方法和热仿真模型的合理性与实用性。     

空间太阳能电池阵列模拟器的散热系统设计

针对大功率空间太阳能电池阵列模拟器的小型化要求,设计了一种2U机箱内实现2 400 W功率的高功率密度强迫风冷散热系统。该散热系统采用模块化结构,将整个机箱结构分为线性、投切和Vicor三部分分别建立独立的散热风道,重点研究投切和Vicor两部分的收缩型风道的优化设计。风道优化设计后的散热系统能够满足该设备的大功率散热需求,可将元器件的最高壳温控制在88℃,并通过有限元仿真和热实验进行验证,设备内器件都能够安全可靠地工作。     

极速驶入DX11时代 海尔超越T6铂金版

铂金版海尔超越T6笔记本电脑外观以保时捷Panamera为设计灵感来源,将点、线、面等数字造型模式的多种组合运用到笔记本外观中,让海尔超越T6铂金版充满灵动气息。为保障整机长时间稳定运行,海尔在原有的蜂巢式散热系统的基础上,引入双风道高效双层铜管的Thermal模组以提升散热效果。     

防爆变频器水冷散热系统研究

根据井下大功率防爆变频器的特点,设计了防爆变频器水冷散热系统。该系统采用防爆壳体内部散热风机冷却+外部循环水系统冷却的散热方式,可将水箱中水温控制在某一范围内,保证变频器的进水温度,从而降低变频器腔内的发热量。测试结果验证了该系统的有效性。     

汽车下护板对发动机舱散热性能的影响

为提高汽车发动机舱的散热性能,通过计算流体力学数值仿真研究汽车下护板对整车散热性能的影响。研究表明：在高速工况下,增加下护板后格栅和冷却模块进气量增加;在高负荷工况下,下护板可改善发动机舱的空气温度分布形态。下护板开口可增加冷却模块进气量,不开口时舱内温度较低,所以在整车设计时应综合考虑散热量和热害。下护板能明显减少风阻,但开口会减弱其效果,因此设计时应多方面考虑。     

基于热平衡和结构强度的发动机 分析平台开发及其应用

建立发动机缸体和缸盖的动力学、燃烧和流体有限元模型,进行发动机热平衡、冷却散热和结构强度研究。创建发动机正向设计和分析方法,革新产品开发流程,自主开发热平衡计算平台。建立发动机缸内和水套传热、流体、温度场、强度的计算模型库,设计水套优化方法和流场评价标准,正向计算发动机热平衡和水套散热。通过2个应用案例,证明该平台在发动机热平衡计算和结构分析与评估中的作用。该平台可为发动机热平衡、冷却散热和结构强度的正向设计提供基础。     

基于最优控制策略的逆变器散热结构优化

为了提高电动汽车用永磁同步电机逆变器IGBT模块的可靠性,文章从热损耗和散热两方面对逆变器可靠性进行研究。首先通过对比分析永磁同步电机在同一工况下d轴电枢电流为零(id=0)和最大转矩电流比(MTPA)两种控制方式下逆变器中IGBT模块的损耗,发现MTPA控制策略优于id=0控制策略;接着,基于MTPA控制策略,设计了一种热管和风冷相结合的散热结构,相较原风冷散热结构,采用新型散热方式可使芯片最高工作温度降低8.49℃;最后,采用最优拉丁超立方抽样构建响应面代理模型(RSM),并采用多岛遗传算法(MIGA)对代理模型进行优化处理。经仿真验证,优化处理后的“热管+风冷”散热结构使得芯片最高温度又降低了15.12℃,有效提升了IGBT模块的热可靠性。     

Design of cellular structures for optimum efficiency of heat dissipation

Metal cellular material is a new material attractive for its light weight and potential multifunctionality. In the present paper, we study cylindrical structures made of linear metal cellular material. The outer surface of the cylindrical structure is subjected to thermal boundary condition, and cooling fluid is forced through the cylinder to remove heat through the inner cell walls. Optimum design aims at maximization of heat dissipation efficiency under prescribed flow pressure. Two classes of design variables, relative density, and local aperture distribution of cellular material are to be determined by optimization under given total material volume constraints. Although similar to the structural topology optimization concept of material distribution, our formulation results in a structure with realistic cellular material of finite-sized aperture. Numerical results for different cross-sectional shapes and thermal boundary conditions are presented. Interestingly, our present formulation leads to optimum designs for cellular structures that mimic natural biomaterials. We discuss in general the guideline for cellular structure design to maximize heat dissipation efficiency based on insights from these optimization results.     

Novel heat dissipation design for light emitting diode applications

The authors offer a new design in support of efficient heat dissipation for light emitting diodes (LEDs). In the first part of this paper we discuss improvements in LED packaging materials and layer assembly, and then describe the addition of a thin layer of electroplated copper to the LED base assembly to reduce thermal resistance and increase thermal diffusion efficiency. Also described is a three-dimensional finite element simulation that we performed to verify the proposed design (0.75, 1, and 3 W LED chip temperatures) and a LED heat transfer behavior analysis. The results indicate that the addition of a 9 mm² electroplated copper layer to the LED base assembly improved LED thermal dissipation by reducing chip temperature by 5°C compared to LEDs without the copper layer packaging. In the second part of this paper we describe (a) our heat pipe system/heat sink design for LED illumination, and (b) experiments in which we changed both working fluid mass and rotation angle to determine their effects on heat pipe cooling. Our results indicate that the most efficient heat dissipation occurred when an added heat pipe was arranged horizontally. Good heat dissipation was observed for heat pipes containing 2.52 g of water (temperature reduced by 50°C). Larger water volumes failed to dissipate additional heat due to the presence of steam inside the pipe.     

高速电主轴瞬态温度场分析与测试

研究数控机床主轴温度优化控制问题,高速电主轴系统热变形影响机床加工精度。由于高速电主轴是一个复杂的非线性系统,对温度优化控制较困难。为精确了解高速电主轴系统瞬态温度场分布,采用MSC.Marc软件接触热阻,以多体接触的方式,对电主轴系统不同转速工况下进行有限元仿真分析,并通过现场验证仿真结果。结果表明,系统温度场分布不均,冷却水将系统分成高、低温区域;定子温度随转速非线性变化,转速3000rpm以上温度增长较快。以分析和测量结果为基础,利用冷却水降温。根据定子发热量随转速的变化规律,实时进行控制。测试结果证明,对高速机床温度测量精度效果好,为设计提供了依据。     

Topology optimization of fluid flow channel in cold plate for active phased array antenna

This article presents a topology optimization method for the design of the fluid flow channel of cold plate, aiming to solve the problem of heat dissipation for power devices in active phased array antenna (APAA). The density-based topology optimization method is used in the topology optimization design of flow path, in which the conjugate heat transfer analysis is performed. In the numerical experiment, we use the central plane of the cold plate to make a two-dimensional topology optimization, and then the result of two-dimensional topology optimization was used to build the three-dimensional flow channel of cold plate. The results of simulation show that the optimized flow channel has a better ability of heat dissipation compared with the traditional S style flow channel, which provides important reference for engineering application.     

A pin fin microheat sink for cooling macroscale conformal surfacesunder the influence of thrust and frictional forces

Conventional microheat sink design primarily focuses on the use of continuous fin arrays to optimally dissipate thermal energy from electronic components. By contrast, this paper experimentally measures the thermal and structural performance of two micro pin fin heat sinks designed for use in load bearing applications such as mechanical seals and thrust bearings. One pin fin array is of low porosity, which is more optimal for load bearing capacity, and the other is of high porosity, which is more optimal for heat dissipation. By using these two extreme cases, the thermal-structural tradeoff found in load bearing microheat sinks is demonstrated. The heat sinks are constructed of nickel, electrodeposited onto a stainless steel thrust ring using a modified LIGA technique. Under forced air cooling, the thermal performance of each is compared to a simple model based on a combination of macroscale pin fin heat sink results and classical correlations for fins in cross flow. The low porosity design is also tested under the application of a 44.5 N thrust load at 2500 rpm and found to be structurally sound. Experimental temperature profiles demonstrate a substantial benefit of the microheat sink in cooling the load bearing surface     

计算机CPU芯片散热技术研究

在对计算机CPU散热技术研究的重要作用进行分析的基础上,探讨了当前计算机CPU芯片风冷散热技术及其特点。最后,结合具体的设计实例,采用温度数值模拟软件对之进行了模拟分析,得到了CPU芯片散热器性能随着其结构尺寸变化的规律,为提高CPU散热性能起到一定的参考。     

锂离子动力电池包CFD仿真

针对电动汽车锂离子电池包设计过程中需要注意的散热问题,通过对某电池包模块的几何模型进行简化建立相应的计算模型,通过FLUENT仿真,从多个角度分析不同设计方案对电池包散热性能的影响.通过对仿真结果的对比和分析,发现随着电池包进口风速的增加,电池包的散热性能逐步提升;但超过一定速度后,进一步提升进口风速对电池散热性能的提升效果有限.电池叉排比顺排散热性能要好;随着电池间距的增加,电池包的散热性能随之提升,且改变纵向间距对散热性能的影响大于改变横向间距;边界距离对电池包散热性能的影响较大,距离的减小能提升电池包的散热性能.