热分析软件在机箱散热中的应用

介绍了使用Icepak热分析软件对大功率机箱进行热仿真和热设计,通过仿真数据对机箱所采取的散热措施进行对比分析,以获得一种较为合理的热设计形式,满足机箱散热的要求     

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。     

基于FC-770的板翅式液冷冷板的热设计与热分析

为满足大功率机载电子设备当今越来越高的散热需求，文中设计了一种基于液冷工质FC-770的板翅式液冷冷板主动散热技术；为了强化该冷板的换热能力，在冷板工质流动的槽道增加了强化换热的翅片设计；为验证该冷板的散热能力，采用CFD数值模拟技术对所设计的板翅式液冷冷板进行了热分析计算，分别针对五种不同工质进口温度工况开展了热仿真与热模拟工作，并对数值仿真计算结果进行了有效分析。依据数值仿真计算结果的显示，针对机载大功率电子设备所设计的板翅式液冷冷板可以有效控制电子设备温度在55℃以下，温度均匀性优于3℃，满足当前机载电子设备的散热需求；文中提出的散热方案和研究结果具有工程应用价值，为大功率机载电子设备热控系统的设计和数据提供有力支撑。     

电子设备强迫风冷设计的计算机仿真

介绍了应用Ansys/Flotran热设计仿真分析软件来进行电子设备强迫风冷设计的计算机仿真的原理和方法。仿真测试结果表明，误差较小，能较真实地反映强迫风冷散热的情况。     

大功率CCD焦面组件流体回路温控设计

为了实现大功率焦面组件的热控制,分析了焦面组件热设计的特点,采用单相流体回路控温系统进行散热.以某大功率拼接CCD为例,给出了具体热设计方案,并通过简化的散热分析模型,计算得出了焦面组件最高温度在26.5℃.应用NX高级仿真模块对回路控温系统进行瞬态仿真分析,结果表明:CCD组件在200 s时刻温度达到27℃左右,并维持稳定.所获得的仿真分析结果与理论计算结果吻合较好,最终结果能够满足热控指标要求.     

电子设备强迫风冷散热特性测试与数值仿真

针对电子设备发热导致其可靠性下降的问题,对某电子设备机箱内部PCB（Printed Circuit Board）板强迫风冷的散热特性进行热测试实验,利用热分析软件ICEPAK对该设备的工作情况进行热仿真,并比较实验结果和仿真结果,结果表明二者一致性较好．分析数值仿真产生误差的因素并提出改进数值仿真的方法．该研究表明数值仿真可以为电子设备的热设计开发提供依据．     

ATCA服务器散热系统的热仿真分析

抗恶劣环境ATCA服务器是否能够承受温度冲击直接影响着产品的可考性.为了确定ATCA加固服务器在环境温度急剧变化时的适应性,对该设备的散热系统进行了热仿真分析,并对其进行了优化设计.     

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。     

电子设备热仿真及优化技术研究

阐述了电子设备热仿真的必要性,利用Icepak软件对某电子设备初始方案进行了热仿真,不能满足系统热控制要求。在对原设计方案仿真结果分析基础上,采用热管冷板的化优化方法提高系统散热性能,经仿真能满足系统热控制要求,实验测试结果验证了仿真结果的可靠性。同时分析了热仿真和实验测试的相互关系,提出了热分析软件的优越性。     

灵巧视频卫星推进系统的热控制

为了预示灵巧视频卫星推进系统的在轨温度,解决低加热功耗推进系统的保温问题,对其推进系统进行了热控设计.首先,通过合理分配有限的功耗对推进系统进行了主动热控设计,利用帆板温度、包覆多层等方法对其进行了有效的被动热控设计.接着,建立热分析模型,对热分析参数进行了确定,利用热分析软件对模型进行了仿真,结果表明,各测温点温度在12～23℃之间,满足设计要求.最后,对推进系统在整星条件下进行了热平衡试验,试验结果表明:推进系统各主要测点温度在10～21℃之间,与分析结果基本一致.在轨仿真与试验所得数据验证了热设计的正确性.     

Thermo-Fluids Provisioning of a High Performance High Density Data Center

Consolidation and dense aggregation of slim compute, storage and networking hardware has resulted in high power density data centers. The high power density resulting from current and future generations of servers necessitates detailed thermo-fluids analysis to provision the cooling resources in a given data center for reliable operation. The analysis must also predict the impact on the thermo-fluid distribution due to changes in hardware configuration and building infrastructure such as a sudden failure in data center cooling resources. The objective of the analysis is to assure availability of adequate cooling resources to match the heat load, which is typically non-uniformly distributed and characterized by high-localized power density. This study presents an analysis of an example modern data center with a view of the magnitude of temperature variation and impact of a failure. Initially, static provisioning for a given distribution of heat loads and cooling resources is achieved to produce a reference state. A perturbation in reference state is introduced to simulate a very plausible scenario—failure of a computer room air conditioning (CRAC) unit. The transient model shows the “redlining” of inlet temperature of systems in the area that is most influenced by the failed CRAC. In this example high-density data center, the time to reach unacceptable inlet temperature is less than 80 seconds based on an example temperature set point limit of 40°C (most of today's servers would require an inlet temperature below 35°C to operate). An effective approach to resolve this issue, if there is adequate capacity, is to migrate the compute workload to other available systems within the data center to reduce the inlet temperature to the servers to an acceptable level. Recommended by: Ahmed Elmagarmid     

On energy efficient flow provisioning in air-cooled data servers

This study considers how to efficiently manage the thermal state of data servers by provisioning their cooling airflow dynamically. It introduces a thermal network framework that is tailored to capture the temperature dynamics of the on-board thermal inertiae. On top of this modeling, it devises LeakageCooling, a novel flow provisioning controller that balances the temperature dependent leakage dissipation within the electronic chips and the power consumed by the local fans to produce the cooling airflow. The prediction capabilities of the proposed modeling and the overall control performance are assessed over several relevant experimental scenarios on an Open Compute Windmill V2 server.     

Runtime data center temperature prediction using Grammatical Evolution techniques

Data Centers are huge power consumers, both because of the energy required for computation and the cooling needed to keep servers below thermal redlining. The most common technique to minimize cooling costs is increasing data room temperature. However, to avoid reliability issues, and to enhance energy efficiency, there is a need to predict the temperature attained by servers under variable cooling setups. Due to the complex thermal dynamics of data rooms, accurate runtime data center temperature prediction has remained as an important challenge. By using Grammatical Evolution techniques, this paper presents a methodology for the generation of temperature models for data centers and the runtime prediction of CPU and inlet temperature under variable cooling setups. As opposed to time costly Computational Fluid Dynamics techniques, our models do not need specific knowledge about the problem, can be used in arbitrary data centers, re-trained if conditions change and have negligible overhead during runtime prediction. Our models have been trained and tested by using traces from real Data Center scenarios. Our results show how we can fully predict the temperature of the servers in a data rooms, with prediction errors below 2 °C and 0.5 °C in CPU and server inlet temperature respectively.     

Proactive thermal management in green datacenters

The increasing demand for faster computing and high storage capacity has resulted in an increase in energy consumption and heat generation in datacenters. Because of the increase in heat generation, cooling requirements have become a critical concern, both in terms of growing operating costs as well as their environmental and societal impacts. Presently, thermal management techniques make an effort to thermally profile and control datacenters’ cooling equipment to increase their efficiency. In conventional thermal management techniques, cooling systems are triggered by the temperature crossing predefined thresholds. Such reactive approaches result in delayed response as the temperature may already be too high, which can result in performance degradation of hardware.     

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。     

一种微腔型PCR集成芯片的设计及其热分析

设计了一种新型的硅微聚合酶链式反应(PCR)芯片.该芯片采用掺杂半导体作为加热电阻来提高加热效率,改善反应腔内的温度均匀性.集成在芯片底部的Pt温度传感器与微加热器组成温度控制单元,为PCR反应过程提供所需的三种特定温度.此外,为了便于温度校准,设计了敞开式的反应腔,其容积约1.78 μL.采用集总参数法计算了芯片在加...     

空间机械臂电磁制动器温升最优设计及热真空实验

采用遗传算法几何惩罚函数的方法对空间机械臂制动器电磁线圈温升进行了优化设计.首先针对空间机械臂电磁制动器对电磁力、电流以及磁场强度的限制要求,以温升为目标推导出优化模型.然后针对优化模型约束非线性问题,提出遗传算法结合惩罚函数的优化方法.本方法可在解决全局优化问题的同时保证计算过程中的解总是可行解.优化结果显示,线圈温升大大降低.最后,将制动器置于热真空环境模拟设备中,测出电磁制动器线圈温升曲线.实验结果显示,测得温升值与优化设计得出目标温升值基本吻合,验证了方法及设计的正确性.     

基于热成像的机房热点成因自动诊断方法

服务器设备的异常高温在机房内部会形成热点,不仅会影响服务器的稳定和寿命,还会导致机房制冷效率的降低,从而增加机房的制冷能耗,增加运营费用。导致产生热点的原因有很多,例如空气流通不畅、风扇失灵、长时间满负荷运行等等。通过自动诊断热点的成因,可以有针对性的消除热点,为机房环境控制提供数据支持,有助于降低机房制冷能耗。根据热像仪拍摄的服务器出风口一侧的红外图像,利用人工智能技术,提出了自动诊断热点成因的方法。针对实际工程应用中热点样本数量不足的问题,提出了基于深度卷积对抗生成网络(DCGAN)合成热点样本的解决方案。通过多组实验验证了方法的有效性,热点成因的诊断准确率约为95%。     

Balance of power: dynamic thermal management for Internet data centers

Internet-based applications and their resulting multitier distributed architectures have changed the focus of design for large-scale Internet computing. Internet server applications execute in a horizontally scalable topology across hundreds or thousands of commodity servers in Internet data centers. Increasing scale and power density significantly impacts the data center's thermal properties. Effective thermal management is essential to the robustness of mission-critical applications. Internet service architectures can address multisystem resource management as well as thermal management within data centers.