海底数据中心散热优化系统的设计与仿真研究

随着电子信息存储设备高能耗密度化的发展趋势,海底数据中心通常需要耗费大量的能源,且其仍存在运行效率较低以及设备能耗较高等问题。研究并设计了一种海底数据中心散热优化装置及其检测系统。首先建立相关模型并分析计算电能利用效率PUE(power usage effectiveness)值,客观地评价海底数据中心散热状况,接着参考工程实例对比不同散热结构并进行仿真实验验证,最后结合散热检测软件平台所监测到的相关数据,印证了散热优化系统能够有效提高海底数据中心的散热效率。     

蒸汽喷射制冷原理在大型翅片散热上的应用

研究了一种利用喷射制冷原理的翅片散热器散热效率提高装置。创新性地将蒸汽喷射制冷原理应用于翅片散热器,可有效提高翅片散热器散热效率,解决因工况环境等因素导致的设备散热不及时等问题,符合绿色环保节能减排发展理念。     

5倍聚光电池散热翅片器件的设计与分析

电池组件的散热设计对于聚光光伏系统十分重要,针对一种5倍聚光电池进行了散热翅片器件的计算与设计,并利用FLUENT软件模拟了该设计方案,根据模拟的结果对该类散热翅片的设计进行了分析与总结。     

风力发电机组机舱散热布局结构最优化方法研究

为得到风力发电机组最优散热布局结构,首先在"下送尾排"式机舱散热布局结构的基础上,提出了"下送侧排"式、"侧送尾排"式和"侧送侧排"式3种机舱散热布局结构;然后通过改变送风口与排风口的位置,运用CFD软件对4种机舱散热布局结构进行温度场数值模拟,采用一种基于热源扰动的温度场均匀性评价新方法,运用MATLAB软件进行插值运算,得到4种机舱散热布局结构送风口与排风口的最佳位置;最后分别通过计算和分析"侧送侧排"式机舱的温度效率和温度场分布云图,进一步验证了"侧送侧排"式机舱有着良好的散热能力。该研究不仅为机舱外形结构设计及其通风散热性能设计提供了参考,同时也为其他机舱模型散热布局的最优结构提供了理论参考与借鉴经验,具有一定的实际工程价值。     

某数据中心用集装箱发电机组多方案流动传热优化分析

数据中心是国家产业转型,释放经济潜力的重要基础设施。而数据中心用集装箱型发电机组具有保障数据中心电力可靠安全重要设备。本文对某集装箱型发电机组进行数值模拟研究,并提出三种改善散热和流动措施,分别为油箱电缆箱优化,改变进气角度,侧边进气方案。结果表明,改善流动对散热作用较好,不论是优化油箱和电缆箱布局,还是改变进气角度,侧边进气方案,都能改善流动,改善散热。此外,研究侧边进气位置对散热影响,结果表明,尾部侧边进气方案效果最好。对散热和流动的改善能够有效降低高温风险,减少耗油率,提升柴油机以及发电机寿命。     

EGR冷却器散热面积计算研究

通过冷却器散热面积计算公式,利用某发动机性能参数,计算出发动机废气再循环装置(EGR)冷却器散热面积,利用数值模拟软件ANSYS对发动机冷却器散热效果进行模拟计算,然后对结果进行分析,从而为某发动机EGR冷却器的设计和计算提供理论依据。     

复杂构态热源对电子设备散热的影响研究

随着电子技术的发展,使得小型电子设备的热流密度不断增加,伴随的散热问题越来越棘手。若电子元件散热处理不佳,不但无法发挥其性能,还会缩短设备使用寿命,甚至引发安全风险。针对不同温度的离散热源间距不同,数量不同,高度不同探究在电子设备散热中的影响。为电子设备散热优化提供理论依据。     

新型12V190柴油机散热水箱研制

介绍一种新型内燃机散热水箱一利用铜铝复合翅片管作为散热元件，论述了其结构特点，论证了其散热效果。     

基于正弦函数的液冷板上流体流向对锂离子电池散热性能的影响北大核心CSCD

锂离子电池的散热性能与液冷板上流道的形状、液流流向、液流入口温度、液流入口流速和放电倍率等有关。本工作以电池最高温度、温差、温度标准差及压降为评价指标,设计了一种正弦函数液冷板流道,运用COMSOL有限元软件分析正弦流道频率与振幅对锂离子电池散热性能的影响并探讨不同放电倍率、不同入口温度和不同入口流速条件下流体流向对锂离子电池的最高温度、温度均匀性和温度一致性的影响。结果表明:低频率和低振幅的正弦函数流道有利于电池的散热;改变流体流向有利于改善锂离子电池的最高温度、温度均匀性和温度一致性;随着交错流次数的增加,锂离子电池的最高温度和温差均减小;高放电倍率下流体流向对锂离子电池散热性能的影响更大;液流入口温度为25℃时,改变流体流向锂离子电池的散热效果最佳。     

基于石墨烯辐射强化散热的变压器过载能力提升技术研究

一般配电变压器的散热系统均未考虑过负荷情况,由于油温过高引发的安全事故时有发生,提出了一种提升变压器过载能力的运行可靠性方案,介绍了石墨烯辐射涂料的特点,基于石墨烯辐射涂料,开发设计了用于变压器强化散热的辅助散热模块,并对设计方案进行了验证,对于负荷波动较大的配电变压器,能有效降低油温,大幅提升现有变压器的辐射传热能力,进而提升变压器的过载能力,具备较好的实用价值。     

利用有限元技术估算内燃机机体表面辐射噪声方法的研究

本文论述了内燃机机体辐射噪声的计算方法.先将机体简化为有限元模型,再计算机体在实际工况下的表面振动速度均方值及辐射效率,最后得到了表面噪声分布图.通过对?Q 6100汽油机机体辐射噪声计算结果与试验数据对比表明,二者结论比较一致.从而证明该方法是可行的,为设计低噪声机体提供了较好的计算方法.     

内燃机辐射噪声三维计算模型

应用声边界元理论建立了内燃机辐射声场三维计算模型，开发了计算程序，利用复式声强测量得到的空间粒子速度分布作为书籍边界条件计算了Ｌ１９５柴油标定工况的辐射声功率及其辐射声场分布。试验结果表明，本内燃机辐射噪声计算模型和计算程序准确可靠，声边界元方法是内燃机辐射声场计算的一种有效方法，为低噪声内燃机设计奠定了基础。     

Hydromagnetic free convection of a radiating fluid

Natural convection of an electrically conducting and radiating fluid in the presence of an external magnetic field is investigated numerically. The two opposing side walls are differentially heated with a temperature difference specified, while the top and bottom walls are insulated. The coupled momentum and energy equations associating with the electromagnetic retarding force as well as the buoyancy force terms are solved by an iterative procedure using the SIMPLER algorithm based on control volume approach. Steady-state conditions are assumed. The finite-volume method is utilised to solve the radiation transport adopting the same computational grid as used in solving the flow field, with which the radiating fluids in an enclosure are assumed to be radiatively opaque, transparent and participating, respectively. After validating the numerical procedures, the changes in the buoyant flow patterns and temperature distribution affected by combined radiation and a magnetic field are focused mainly. Comparative results for the velocity profiles and the heat transfer rates are presented too. Based on the results of this study, it was found that the radiation played a significant role in developing the hydromagnetic free convective flow in a differentially heated enclosure.     

Boundary-Element Solution of Coupled Heat Conduction-Radiation Problems in the Presence of Shadow Zones

Steady-state and transient temperature fields in bodies containing concave, self-irradiating cavities are considered. Radiation and conduction equations are discretized using the boundary-element method. The technique covers nonlinear material and nonlinear boundary conditions. The presence of shadow zones in the radiating cavities is taken into account. The developed visibility algorithm is integrated into the self-adaptive integration technique of evaluating the entries of the radiation matrices. Excellent overall accuracy of this integration is achieved. Discussed problems are in two dimensions, but the technique may be extended to three dimensions. Numerical examples are included.     

Infrared radiative heat transfer in nongray nonisothermal gases

In the present paper, both nongray and nonisothermal behaviors of an infrared emittingabsorbing gas have been taken into account in radiative transfer analyses through the use of the nonisothermal band absorptance. Consideration is given specifically to a simple system consisting of a radiating medium bounded by two infinite parallel black surfaces of different temperatures. Solutions are presented for the cases of radiative equilibrium and combined conduction and radiation. Results based on different methods of evaluating the nonisothermal band absorptance are also compared among themselves. Differences in several fundamental features are exhibited in the nongray nonisothermal solutions as compared to those with nongray but isothermal properties.     

储能设备对孤立风力发电系统的影响

采用序贯蒙特卡罗法对含有储能设备的风/柴孤立发电系统进行充裕度评估。针对样例系统,在发电系统强迫停运率、储能设备容量以及峰值负荷取值不同的情况下,计算发电系统的充裕度指标;研究储能设备对孤立发电系统充裕度的影响,并对产生影响的原因进行分析。结果表明,加入储能设备可改善发电系统的充裕度,提高系统的供电可靠性水平,减少风力发电机组输出功率波动对系统的影响。分析方法和结果可为储能设备在风力发电系统中的应用和储能设备容量的选择等方面提供参考。     

动力电池散热数值模拟分析

通过建立电池温升模型模拟分析了无肋片自然对流电池温升、加肋片自然对流电池温升及加肋片强迫对流电池温升等三种工况下的电池温升特性,并对其中心温度与电池中心平面平均温度的温升特性进行了分析比较.由模拟结果分析可知,随着放电倍率的增大,电池的温升及温差均明显上升,增加肋片散热可以有效降低温升变化,但温差较大.采用强风可以减小...     

Hypersonic radiating merged shock layer near the blunt-body stagnation region

In the low Reynolds number flow, shock wave and viscous layer near the stagnation point of a blunt-body are merged together. This merged shock layer is investigated in this paper for a radiating gas. The radiating transfer is simplified to the emission-dominated case. The basic model of the flow is described by the full Navier-Stokes equations. Using the concept of local similarity, the equations are reduced to an eighth-order set of nonlinear, coupled ordinary differential equations. This set of equations is integrated numerically from the surface to the freestream under different prescribed conditions. Earlier, this problem was investigated by Liu and Sogame [3] within the framework of two thin-layer model. A number of inaccuracies of this analytical development are pointed out. It is shown that the present analysis gives more reliable and accurate information about the detailed behaviour of the radiating viscous flow at low Reynolds number.     

Recent advances in the measurement of strongly radiating, turbulent reacting flows

Recent advances in diagnostic methods are providing new capacity for detailed measurement of turbulent, reacting flows that are strongly radiating. Radiation becomes increasingly significant in flames containing soot and/or fine particles, and also increases with physical size. Therefore many flames of practical significance are strongly radiating. Under these conditions, the coupling between the turbulence, chemistry and radiative heat transfer processes is significant, making it necessary to obtain simultaneous measurement of controlling parameters. These environments are also particularly challenging for laser-based measurements, since soot and other particles increase the interferences to the signal and the attenuation of the beam. The paper reviews the influence of physical scale and of the properties of the medium on approaches to perform measurements in such strongly radiating flows. It then reviews the recent advances in techniques to measure temperature, mixture fraction, soot volume fraction, velocity, particle number density and the scattered, absorbed and transmitted components of radiation propagation through particle laden systems. Finally it also considers remaining challenges to diagnostic techniques under such conditions.