间距对散热器模块匹配性能影响的试验研究

为解决车辆冷却系统中多散热器匹配中常出现的散热能力不足的问题,对某型车辆的散热器模块在风洞测试平台上进行试验研究。试验散热器模块的第一排为中冷器和液压油冷却器,第二排为冷却水箱,第三排是变矩器油冷器。把各排散热器之间的距离调整为0mm、100mm、200mm,分别进行风洞试验。试验结果表明,增大间距可以提高散热器模块总的散热量,但对模块中单个散热器的影响差异很大。在设计中可以通过灵活调整散热器之间的距离使模块更加适合车辆冷却系统的需求。     

内燃机车散热器散热面积与冷却风扇功率的匹配

分析了内燃机车散热器散热面积与冷却风扇功率消耗合理匹配的重要性,分别对散热面积和风扇功率进行了理论计算、优化设计和匹配研究,并对其进行可视化处理,得出几个结论。     

装载机冷却组优化匹配的试验研究

车辆的换热器多集中布置,构成冷却组,冷却组在车辆中起着十分重要的作用。冷却组的合理匹配不仅与各换热器换热能力有关,还与它们的位置有关。以装载机油气水冷却组为研究对象,通过理论计算和试验验证,对现有冷却组结构进行调整,提高了冷却组换热能力,解决了装载机水散热器开锅、液压油散热器和变矩器油散热器散热不好的问题。     

拖拉机空冷系统流场的数值模拟研究

拖拉机在农田作业时行驶速度慢,作业环境差,经常大负荷甚至超负荷工作,容易造成散热不足.本文利用UG建立包括风扇、水箱、空调散热器、机油散热器、空气中间冷却器和拖拉机罩的模型,利用CFD计算流体方法对风扇转速为200 r/min、800 r/min、1400 r/min的空气流动特性分析,结果表明风扇转速为800～1000 r/min时,对拖拉机散热比较有利.     

拖拉机空冷系统流场的数值模拟研究

拖拉机在农田作业时行驶速度慢，作业环境差，经常大负荷甚至超负荷工作，容易造成散热不足。本文利用UG建立包括风扇、水箱、空调散热器、机油散热器、空气中间冷却器和拖拉机罩的模型，利用CFD计算流体方法对风扇转速为200r／min、800r／min、1400r／min的空气流动特性分析，结果表明风扇转速为800—1000r／min时，对拖拉机散热比较有利。     

某型号牵引车冷却模块匹配计算方法

为缩短牵引车用冷却模块匹配选型时间,提出一种牵引车用冷却模块匹配计算方法.以某型号牵引车为计算原型,对由中冷器、散热器和风扇组成的牵引车用冷却模块进行匹配计算,并通过整车转毂热平衡试验检验计算方法的准确性.整车转毂热平衡试验结果表明:本文中提出的冷却模块匹配计算方法能成功预测冷却模块的冷却能力,整车实车试验与理论计算结...     

浅析海上风电机组的散热布置

海上风电发展前景广阔,开发大容量海上风电机组所面临的主要问题包括如何有效地冷却发电机、齿轮箱及变频器等核心部件。通过分析某MW级海上风电机组冷却系统的散热器空间布置形式、散热通道结构设计以及散热器所配风扇性能,利用CFD软件对散热通道内流场进行了三维数值模拟,结果表明,散热器的布置形式直接影响散热通道的系统阻力,进而影响散热器所配风扇与系统的特性匹配。     

高性能商用车用散热器轻量化设计

为提高商用车冷却模块散热性能,实现冷却模块轻量化,采用计算流体动力学方法分析散热器的散热带高度、波峰距、开窗角度对散热性能的影响,得到最佳冷却模块性能参数;对散热器结构进行优化,并对优化后的散热器进行风洞试验和整车热平衡试验。结果表明：优化后的散热器质量减轻17.9%,散热性能提升1%～8%;通过优化散热带高度、波峰距以及开窗角度,可以提高冷却模块散热性能,实现轻量化,降低生产成本。     

汽车发动机机舱阻力系数影响因素分析

以某款牵引车为例,基于质量、动量、能量守恒方程建立机舱内流场仿真模型,采用一维-三维耦合的方法对机舱内流场进行仿真,经试验验证仿真模型正确可行.研究不同发动机、冷凝器前布置方式、风扇与散热器匹配、驾驶室底舱到发动机摇臂罩距离以及驾驶室到车厢的距离对机舱阻力因数(built-in resistance,BiR)的影响.结...     

牵引车冷却系统的匹配优化

分析牵引车冷却系统的匹配优化对降低牵引车油耗的作用,根据牵引车用柴油机的布置特点,分析牵引车冷却系统的工作原理,从柴油机出水温度、散热器散热性能、散热器水侧和风侧的优化方法,以及风扇的匹配和智能控制等方面进行分析,制定牵引车冷却系统匹配优化的方案,并在配套牵引车上进行油耗测量验证,结果表明百km油耗降低0.83 L,优化方案可为牵引车降低油耗提供依据。     

半导体热电堆串、并联发电性能及热电堆复现性研究

对半导体热电堆的复现性进行了实验研究。以此为基础进行了热电堆的串联,并联实验,得到了半导体热电堆串联并联的规律,并用有限差分法对热电堆的各项发电性能指标进行了数值计算,为热电发电技术做了有益的探索。     

Heat pipe cooling technology for desktop PC CPU

As Pentium-IV, a high-performance PC CPU, emerges, CPU’s thermal design power shows sharp increase. Since conventional cooling method, aluminum extruded heat sink has disadvantages like poor cooling performance, acoustic noise increase and weight rise, cooling module in the form of remote heat exchanger using heat pipe is developed. Especially, using system fan exhausting heat inside to cool CPU reduces acoustic noise with lowered quantities of fan and makes it possible to reduce manufacturing unit price. This paper proposes cooling using heat pipe, recommends Pentium-IV CPU cooling module on change of fan revolution speed, and looks for possibility of reducing acoustic noise.     

Influence of fan setting height on the cooling performance of a plate‐fin‐type heat sink with microprocessor

The cooling performance of a plate‐fin‐type heat sink equipped with a cooling fan was investigated experimentally. The heat sink was 80 mm long, 43 mm wide, and 24 mm in height (including the 4‐mm‐thick base). The cooling fan was 40 × 40 × 15 mm and was set to direct the air flow vertically in the downstream half of the heat sink. We focused on the influence of the height (which varied from 5 to 20 mm) that the fan was set at, on the heat transfer coefficient of the heat sink. The maximum value of the heat transfer coefficient was achieved at a setting height of 5 mm. At this height, the volumetric heat transfer coefficient was 1.8 times as high as that in a parallel flow under the same fan power. This result indicates that the cooling performance of heat sinks with a cooling fan can be improved by using this kind of compact structure. © 2001 Scripta Technica, Heat Trans Asian Res, 30(6): 512–520, 2001     

热管用于笔记本电脑智能温控散热的分析

随着笔记本电脑性能的不断提升,传统的单一风冷散热已经满足不了要求,传热性能优越的热管便应用于笔记本电脑散热。分析了热管用于智能温控散热系统的传热机理,并建立了传热模型．分析了用于笔记本散热的热管的热阻和总传热系数,结合实例进行了定量计算。计算结果表明热管配合智能温控风扇,能很好满足笔记本散热的要求。     

复合式土壤源热泵系统设计

设计了一套复合式土壤源热泵性能实验台,采用冷却塔作辅助冷源、太阳能热水器作辅助热源,能够实现冬季供暖、夏季供冷、一年四季提供60~80℃生活热水的功能。给出了系统中热泵机组、空调末端设备、冷却塔、水泵、太阳能热水器等主要部件的选型计算方法,经搭建好的土壤源热泵性能实验台运行测试,制冷和制热效果良好,同时也解决了土壤热平衡问题。     

Dynamic test strategy for diagnosing a heat pipe cooling module

This article experimentally develops a dynamic test strategy for efficiently diagnosing a heat pipe cooling module in order to improve the time-consuming conventional steady-state test. The first step is to investigate the performance of a heat pipe by measuring its thermal resistance, and the next step is to examine the influence of the parameters on the temperature response of the heat pipe cooling module. The experimental parameters include the press force, preheating temperature, heating power, and starting time of the fan. The results show that the thermal performance of a heat pipe, the contact condition between the heat pipe and the base plate, and the heat dissipation ability of a heat sink, are diagnosed within 30 seconds. During the dynamic test, both the startup and the ability to reach uniformity of temperature of the heat pipe can be observed. In addition, the temperature response of a heat pipe cooling module based on a lumped model matches the experimental data.     

Heat transfer and performance characteristics of axial cooling fans with downstream guide vanes

This study examines experimentally the effect of stators on the performance and heat transfer characteristics of small axial cooling fans. A single fan impeller, followed by nine stator blades in the case of a complete stage, was used for all the experimental configurations. Performance measurements were carried out in a constant speed stage performance test rig while the transient liquid crystal technique was used for the heat transfer measurements. Full surface heat transfer coefficient distributions were obtained by recording the temperature history of liquid crystals on a target plate. The experimental data indicated that the results are highly affected by the flow conditions at the fan outlet. Stators can be beneficial in terms of pressure drop and efficiency, and thus more economical operation, as well as, in the local heat transfer distribution at the wake of the stator blades if the fan is installed very close to the cooling object. However, as the separation distance increases, enhanced heat transfer rate in the order of 25% is observed in the case of the fan impeller.     

新型多孔铜微通道热沉散热性能实验研究

新型多孔铜微通道散热技术采用多孔铜微通道结构,增加热沉与冷却工质的接触面积,提高热沉的散热性能。利用单室金属-气体共晶定向凝固工艺,通过控制冷却速度、过热度、气压等工艺参数,从而制备优质的多孔铜材料。根据多孔铜微通道热沉散热原理,搭建散热性能测试平台,研究冷却工质流量、多孔铜材料的孔径和孔隙率、入口截面斜率角对多孔铜微通道热沉散热性能的影响规律。结果表明:增加冷却工质流量有利于提高多孔铜微通道热沉的散热性能;在恒定体积流量下,减小孔径有利于提高多孔铜微通道热沉的散热性能;当多孔铜孔隙率为30.8%时,多孔铜微通道热沉散热性能最佳;入口截面斜率角对多孔铜微通道热沉散热性能的影响较小。     

热管散热技术在小山电站励磁整流系统的应用

针对小山电站2号机励磁系统冷却方式存在的若干问题,对现有励磁冷却方式进行改进,采用热管冷却方式,风扇作为备用。从热管冷却的优点进行了分析比较,通过2号机的实际温升试验,进一步阐明了采用热管技术既简化了冷却风机操作及维护,减少了噪声,也提高了设备的可靠性。     

Heat pipe with PCM for electronic cooling

This article experimentally investigates the thermal performances of a heat pipe with phase change material for electronic cooling. The adiabatic section of heat pipe is covered by a storage container with phase change material (PCM), which can store and release thermal energy depending upon the heating powers of evaporator and fan speeds of condenser. Experimental investigations are conducted to obtain the system temperature distributions from the charge, discharge and simultaneous charge/discharge performance tests. The parameters in this study include three kinds of PCMs, different filling PCM volumes, fan speeds, and heating powers in the PCM cooling module. The cooling module with tricosane as PCM can save 46% of the fan power consumption compared with the traditional heat pipe.