分片式蜂窝冷却夹套的应用

在生产中使用分片式窝夹套,换热效果比传统的整体结构夹套具有明显的优越性。同时,由于分片式结构对设备体进行加强补强,提高了应力水平,使壁厚减薄降低成本,值得推广     

Development and Characterization of Thermal Enhancement Structures for Single-Phase Liquid Cooling in Microelectronics Systems

In this paper, the development and characterization of thermal enhancement structures for single-phase liquid cooling in microelectronics systems are presented. Miniature heat sinks with three different types of thermal enhancement structures were examined. The first type was a metallic microchannel heat sink (MMCHS) made of aluminum with the channel dimensions of 15 mm (length) × 0.2 mm (width) × 2 mm (height). The second type was the silicon microchannel heat sinks (SMCHS) made through the deep reactive ion etching technique on a 6 inch wafer, with identical channel height of 0.45 mm and average channel widths of 66.6 μ m and 46.6 μ m, respectively. The last type was the metallic foam heat sinks (MFHSs), which were formed by brazing porous foam materials of high pore density onto copper base plates. All three types of heat sinks were fabricated and experimentally characterized by incorporating into electronic packages in standard flip chip ball grid array format. Characterization results indicate that, given a thermal window of 50°C, both the MMCHS and MFHSs can achieve an equivalent package heat dissipation above 100 W/cm² at moderate pressure drops and the SMCHS above 200 W/cm² at larger pressure drops. A comparison of thermal enhancement and manufacturability of the three types of heat sinks is also presented.     

蜂窝内冷通道布局对叶片冷却效率的影响研究

为提高涡轮叶片耐温能力,将蜂窝冷却通道应用于涡轮叶片内部,通过流热耦合计算研究蜂窝冷却通道叶片的传热流动特性。对蜂窝冷却通道的参数化方法进行研究,将蜂窝通道拆分成两种基本结构单元,即可方便调整蜂窝通道的几何参数;使用增材制造的叶片进行实验,通过对比数值计算与实验的冷却效率,验证了数值方法的准确性;在冷却二次流占比1%条件下,在原型蜂窝通道的基础上进行蜂窝通道空间布局和直径分布的调整,利用冷却效率、压降及相对阻力系数衡量不同通道的流动传热特性。研究表明：蜂窝通道由于增大换热面积以及增加分叉点强化换热,冷却效率提高到0.525,压降升高至229.1 kPa;通过调整蜂窝几何参数可以优化蜂窝通道的传热与阻力特性,通过增加蜂窝通道层数、增大次通道直径可以提高冷却效率,通过增加蜂窝通道入口数、增大主通道直径可以减小压降。     

Modeling of a Microchannel Evaporator for Space Electronics Cooling: Entropy Generation Minimization Approach

The increasing heat dissipation from electronic devices on board satellites makes it necessary to find solutions for their cooling. In the present case, 20 electronic components in series need to dissipate a heat flux of 20 kW/m² owing to microevaporators mounted in a refrigeration system. An approach for optimizing the design of the evaporators based on the entropy generation minimization is presented here. To solve this thermal problem, a steady-state three-dimensional conduction model is combined with thermohydraulic flow boiling models valid for microchannels. The best design corresponds to an aspect ratio (ratio between height and width) around 8.8. The sensitivity of the results to the choice of the flow boiling models is also analyzed.     

汽车发动机冷却系仿真优选方法的研究

介绍了汽车发动机冷却系散热器、风扇和水泵的仿真优选方法。建立了散热器性能计算模型,提出了散热器优选的方法。通过收集不同结构形式的风扇和水泵的试验数据,建立风扇性能数据库,应用相似理论,对风扇和水泵进行优选,给出了应用实例。     

Evaluation of Jet Impingement,Spray and Microchannel Chip Cooling Options for High Heat Flux Removal

Thermal management for high heat flux removal from microelectronic chips is gaining critical importance in many earth-based and space-based systems. Heat fluxes greater than 1 MW/m² (100 W/cm²) have already been realized in high-end server applications, while cooling needs in next generation chips and advanced systems such as high-power electronics and electrical systems, pulsed power weapons systems, solid-state sensors, and phased-array radars are expected to reach 5–10 MW/m² (500–1000 W/cm²). After evaluating the contributions from different thermal resistances in the chip-to-ambient thermal path, this paper presents a critical review and research recommendations for three prominent contending technologies: jet impingement, spray cooling, and microchannel heat sinks.     

整车冷却系统优化匹配方法浅谈

对整车冷却系统的优化匹配方法进行介绍。首先采用适当的试验方法对相关零部件的性能进行测试,获得完整的性能数据。这不仅可以对特定部件进行全面评价,也使零部件的试验更好地为冷却系统匹配分析提供有价值的参考数据。如果条件允许则可利用CFD的模拟分析手段,整车风洞试验或整车道路试验是整车冷却系统匹配优化的最终评价手段。     

190系列柴油机新型冷却系统的开发

本文介绍190系列柴油机新型冷却系统的开发重点叙述关于冷却系统关键部件的结构特点和理论分析及试验结果该系统经装机试验得到较理想的效果     

远洋船舶低低硫燃油冷却系统研究

针对低低硫船用燃料黏度较低,无法达到船舶主辅机燃用要求的问题,开发了一种船舶低低硫燃油冷却系统。样机验证表明:该系统能精确控制出口燃油温度,燃油温度波动在1℃以内,同时能够满足不同出油温度要求;产品满足船用低低硫燃油供油系统的各项要求。     

发动机冷却系统开发探讨

冷却系统是发动机是重要部件总成.本文对汽车发动机冷却系统开发,由发动机试验数据,结合商用软件1D概念设计,运用CFD(3D)进行整车热管理优化.为整车汽车的动力系统的提出更高的燃油经济性,动力性.因此,发动机冷却系统的正确设计对汽车的正常运行至关重要.     

Cooling System Design

Cooling water systems and refrigeration systems are required to provide cold utility to chemical processes. Little attention has been placed on the structure and system interactions between cooling systems and processes. In this article, an integrated design and retrofit method for cooling systems is reviewed. For cooling water system design, a new design methodology has been developed for debottlenecking of cooling water systems. Reuse of cooling water between different cooling duties enables cooling water networks to be designed with series arrangements. This allows better cooling tower performance and increased cooling tower capacity. The interactions between the performance of the cooling tower and the design of cooling water networks are explored systematically. For refrigeration system design, a systematic design and retrofit method has been proposed for refrigeration systems using pure or mixed refrigerants. A graphical exergy analysis method, the z -H diagram, is introduced to help engineers obtain understanding and insights into complex refrigeration systems. The systematic synthesis method proposed in this article can greatly improve operating efficiency for refrigerant systems.     

建筑物窗体与玻璃的节能性分析

1玻璃窗能耗的来源-空气渗透漏热、温差传热、太阳辐射得热 玻璃窗由窗框（包括框架、密封件、五金件）及玻璃构成。隐性玻璃幕墙虽然从外部看不到边框，但实际上也有不透明的框架部分。     

某皮卡冷却系统的优化设计

针对汽车在行驶过程中出现水温过高,有些情况甚至出现水温接近红线并报警的问题,利用模拟仿真技术对汽车冷却系统进行研究分析,确认故障并通过试验验证优化效果。     

电-袋复合型除尘器的开发和应用

讲述了电-袋复合型除尘器的原理、结构、特点、开发和应用。     

车用内燃机冷却系统动态传热模型

提出了一个基于集总参数法的车用内燃机冷却系统动态传热模型。考虑了内燃机燃烧室、散热器和水泵的传热和冷却系统的工作,建立了机体、散热器、水泵与冷却介质之间的热耦合计算公式。对一台单缸柴油机冷却系的稳态及动态温度进行了计算,结果证实该模型可用于内燃机冷却系统的动态传热特性研究。     

A Flow Boiling Microchannel Evaporator Plate for Fuel Cell Thermal Management

In order to provide a high-power density thermal management system for PEM fuel cell applications, a flow boiling microchannel evaporator plate has been developed that operates in a closed loop two-phase thermosyphon. The flow is passively driven by gravity, and the flow rate initially increases with increasing evaporation rate and then decreases after reaching a peak flow rate. A microchannel plate has been fabricated with 56 square channels that have a 1 mm × 1 mm cross-section and are 115 mm long. The working fluid, HFE-7100, has been chosen due to its favorable saturation temperature at one atmosphere. Experiments have been conducted with the heat flux as the control variable. Measurements of mass flow rate, temperature field, and pressure drop have been made. The flow regimes are predominately bubbly and slug. The maximum heat flux observed, 32 kW/m², is an order of magnitude greater than that required in current fuel cells and is limited by a Ledinegg instability. Two-phase thermal hydraulic models give a reasonable prediction for the mass flow rates and wall temperatures using standard flow boiling correlations. This paper will thoroughly describe the performance of the two-phase thermal management system over a wide range of operating conditions.     

冷管型太阳能制冷系统

太阳能吸附式制冷作为一种绿色环保型的制冷技术具有良好的应用前景。本文分析了一种吸附床可直接吸收太阳能的、自身完成集热与制冷的玻璃管型太阳能吸附式制冷管,并介绍了以该冷管为基础的太阳能制冷系统。     

单一地板辐射供冷空调方式适用区域的划分

叙述了不加置换通风等其他空气处理方式单一地板辐射供冷空调系统的局限性和可行性以及结合中国各主要城市逐时气象参数,对普通住宅建筑,划分了单一地板辐射供冷空调方式的适用区域。     

车用柴油机冷却系统的优化设计

在柴油机设计开发过程中,考虑到热负荷高、各缸孔间冷却均匀性差、缸盖鼻梁区出现热裂等现象的出现,本文对整机冷却水流速与换热进行模拟分析.通过模拟计算分析,得出冷却水在缸体进气侧从第一缸向第四缸流动过程中,流速与换热系数明显下降,这将会引起柴油机热负荷高、冷却均匀性差;喷油器和气门周边区域换热系数低,这将会是缸盖鼻梁区热裂的主要成因.针对上述设计开发过程中首先要考虑的潜在影响因素,本文提出了缸体水套设计优化方案、缸盖垫片优化设计方案;通过模拟计算的手段,得出本文提出的冷却系统优化设计方案,通过该方案的实施,有效降低产品设计完成后热负荷高、冷却均匀性差以及缸盖鼻梁区热裂等潜在失效风险.     

车用柴油机冷却系统的优化设计

在柴油机设计开发过程中,考虑到热负荷高、各缸孔间冷却均匀性差、缸盖鼻梁区出现热裂等现象的出现,本文对整机冷却水流速与换热进行模拟分析。通过模拟计算分析,得出冷却水在缸体进气侧从第一缸向第四缸流动过程中,流速与换热系数明显下降,这将会引起柴油机热负荷高、冷却均匀性差;喷油器和气门周边区域换热系数低,这将会是缸盖鼻梁区热裂的主要成因。针对上述设计开发过程中首先要考虑的潜在影响因素,本文提出了缸体水套设计优化方案、缸盖垫片优化设计方案;通过模拟计算的手段,得出本文提出的冷却系统优化设计方案,通过该方案的实施,有效降低产品设计完成后热负荷高、冷却均匀性差以及缸盖鼻梁区热裂等潜在失效风险。