共查询到19条相似文献,搜索用时 312 毫秒
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对以水为换热介质的微通道冷却器对模拟发热电子芯片进行冷却的换热性能进行了实验研究.通过测量流体的流量、进出口温度、发热片表面热流密度,获得了不同几何结构微通道冷却器在不同加热功率、不同Re数条件下的换热特性和冷却效果.结果表明,微通道冷却器可以有效地对表面热流密度高达5.34×105 W/m2的发热电子芯片进行冷却;微通道冷却器的换热性能随Re数的增大而提高,所提高的幅度随加热功率的增大而增大;微通道的几何结构对换热性能有显著影响,平均Nu数随微通道的宽深比增大而增大. 相似文献
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基于Abaqus的催化器总成热循环应力分析 总被引:1,自引:0,他引:1
基于Abaqus的稳态热分析和热力耦合分析功能,在给定热边界条件下计算某催化器总成稳态热分布;利用Abaqus的顺序耦合功能计算催化器总成在循环温度下的热应力,得到关键部件处的热应力和塑性应变.根据结果初步评价该催化器总成在热循环冲击载荷下的强度特性,为热冲击试验和结构优化提供参考. 相似文献
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为解决火电厂及工业生产领域中大功率电动机背包式水冷却器因发生管裂漏水、管面结露而危及电机安全运行的问题,应用热管理论和技术成果,设计了热管式气- 水冷却器取代原来的冷却器。利用热管的换热特性、设计方法、制造工艺和结构特点等,论述了解决上述问题的理论和实践的可行性,做到即能满足换热要求,且所需费用少、实施难度小、不改变原有设备及系统。 相似文献
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在潜射导弹水下发射装置优化设计的研究中,冷却器中冷却水的喷注对燃气蒸汽弹射过程有着重要影响.为了研究喷水对冷却器内流场的影响,采用Mixture多相流模型和汽化模型建立燃气与冷却水相互作用的气液两相流场数值模型.通过与相关实验对比,验证了数值模型的可靠性.采用建立的数值模型研究了发射过程冷却器内喷水和不喷水流场,获得了喷水和不喷水状态下冷却器出口温度和压力随时间变化规律和流场结构.结果表明:冷却水可以显著降低冷却器出口温度和压力;喷水工况下高密度水介质对二级喷管处高温燃气射流具有阻滞作用.研究结果为燃气蒸汽弹射冷却器结构设计提供理论基础. 相似文献
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鞭炮捆筒机在工作过程中,电机到主轴采用皮带传动.火药靠皮带的两侧面与轮槽侧面压紧产生摩擦力进行动力传递的,在摩擦热载荷作用下会诱发机器结构的振动.传统的PID振动控制方法需要大幅调整参数,去满足热载荷作用下的振动控制要求,容易引发参数过量失调,振动控制效果不佳.提出基于模糊自适应PID控制算法的鞭炮捆筒机热冲击振动消除方法.计算V带基准长度,通过运算获取实际中心距离,研究了鞭炮捆筒机带轮振动关系.计算热冲击振动信号与控制参数之间的关联性,并对热冲击振动信号进行离散化处理,对离散化处理结果进行误差补偿,实现热冲击振动消除.实验结果表明,利用改进算法进行鞭炮捆筒机热冲击振动消除,能够有效提高消除的准确性,提高鞭炮捆筒机的应用价值. 相似文献
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ATCA服务器散热系统的热仿真分析 总被引:1,自引:0,他引:1
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. 相似文献
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Glassmakers monitoring a rolled plate process suffered discomfort from the high temperature environment. This was caused by the radiant heat emitted by the furnaces and associated equipment surrounding the glassmakers' working area, combined with a high air temperature. The glassmakers are responsible for monitoring the glass rolling machine to ensure that the product is manufactured to specification, and to prevent the molten glass sticking to the rollers. This study improved their thermal comfort by the construction of a cool area. They were also brought nearer to the rolling machine. This, with the addition of a cooler environment, improved their monitoring performance. The cool spot was constructed using glass and aluminium radiant heat shields, air curtains and low velocity cooling air. 相似文献
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对硼回凝水冷却器用有限元法建立计算模型.并进行在自重、压力和接管栽荷条件下的静态分析、模态分析和地震载荷下的动态反应分析。求得硼回凝水冷却器的应力.同时按规范要求,对硼回凝水冷却器在各使用限制条件下进行载荷组合和应力评定。评定结果表明:硼回凝水冷却器的各部件均满足ASMEIII-ND和NF规范的相关要求。 相似文献
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Abstract— A thermal shock test was carried out using high‐strain‐point glass substrates for plasma‐display panels. From the fracture analysis, the fracture stress was determined and compared with the initial edge strength. It was observed that the edge strength greatly decreased because of micro cracks that formed on the glass surface during testing. Therefore, it is important to prevent the formation of micro cracks in order to avoid failure as well as to minimize thermal stress in the process. Fatigue is also an important parameter in preventing the failure of the glass substrate when the stress on it lasts for a long period of time. 相似文献
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微热对流角速度传感器是一种新型的惯性传感器件,由于采用流体代替传统的固体质量块作为敏感载体,因而具有极其独特的性能,特别是高抗冲击性。采用ANSYS有限元分析软件,对微热对流角速度传感器的加热丝支撑层和检测丝支撑层进行动静态变形和应力计算,得出应力最大点,微加热丝支撑层的应力最大点在固支位置附近,检测丝支撑层的应力最大点在固支位置附近和内拐角处。在z方向有一定加速度载荷作用下,加热丝支撑层的最大应力比检测丝支撑层的最大应力大,更容易破坏。理论计算得到微热对流角速度传感器样品可抗冲击200000gn,经过抗冲击实验验证,微热对流角速度传感器样品在21200gn的冲击下仍完好无损,有极好的抗冲击性能。 相似文献
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连续搅拌釜式化学反应器(CSTR)是重要的化工设备。对蛇管与夹套双冷却CSTR单回路温度控制方案只利用一种操纵变量,无法兼顾动态性能与静态性能的不足进行了深入分析后,提出了CSTR温度双重控制系统方案。通过双重系统的协调控制,在温度出现偏差时由蛇管冷却器快速消除温度偏差,使温度迅速返回设定值;然后由冷却效率高的夹套冷却器逐步取代蛇管冷却器所承担的冷却负荷变化——即在动态过程,由动态性能好的操作变量(蛇管冷却器)进行控制,过渡过程短,动态偏差小;在平稳生产过程,CSTR冷却负荷主要由静态性能好的操作变量(夹套冷却器)承担,冷却效率高,冷却水用量少。CSTR温度双重控制充分发挥了CSTR蛇管与夹套冷却器各自的优势,使CSTR温度控制的动态性能与静态性能都达到较为理想水平。最后,通过半实物仿真实验验证了CSTR温度双重控制在动态性能和节能降耗二方面的优越性。该双重控制方案可应用于具有类似结构特征的其他生产系统。 相似文献
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We measured and calculated shock responses due to the thermal stick–slip phenomenon in hard disk drives. We first measured the stress wave propagation and found that a stress wave travels over the entire top cover of the drive in 30?μs at two velocities: 4.66 and 2.97?km/s. These are the velocities of longitudinal and distortional waves in a plate, respectively. The position error signal responded in 55?μs after the thermal stick–slip phenomenon happened. We then conducted a numerical analysis of wave propagation. The resultant stress wave propagation and the position error corresponded well to the measured ones. We found that the propagation path which leads overwriting on adjacent tracks is through the actuator to the head, not through the spindle motor to the disk. We concluded that stress waves can be detected with a shock sensor before they arrive at the head if the sensor is located at the pivot bearing or the actuator, which are on the propagation path. 相似文献
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The application of a direct numerical computation to superfluid phenomena was attempted. The propagation of a thermal shock wave was numerically simulated by applying a finite-difference method to the two-fluid equation for superfluid helium (He II). Typically, three types of thermal shock waves, namely a frontal shock, a back shock and a double shock, are well simulated, all of which grew from a finite-amplitude second sound wave. The result, however, suggested the necessity for introducing the effect of the interaction of a shock with a tangled mass of quantized vortices to the governing equation in the breakdown state, i.e. in the superfluid turbulent situation. The effect was taken into account on the basis of the Gorter-Mellink mutual friction formula, or on the basis of the equation of the vortex line density evolution proposed by Vinen. The computational results were found to agree qualitatively with experimental data. 相似文献