Measurement of the coolant flow rate using correlation of temperature fluctuations

The transit time of the coolant, and thus its velocity, has been measured using the temperature fluctuation at the outlet of a reactor core. An impulse response function estimation is introduced, which substitutes the widely used cross-correlation measurement technique. It is shown in theory and practice that the time delay estimation is improved when using the impulse response function instead of the cross-correlation function in parameter estimation. Extremely low velocities (down to 2 cm/sec) have been measured in a natural circulation regime in a research reactor.     

空调压缩机用冲压外圈滚针轴承

着重分析空调压缩机采用新的环保型冷媒体后，常规结构滚针轴承的破坏情况，提出了冲压滚针轴承新的结构改进设计及其开发和性能比较结果，为今后新冷媒体空调压缩机的广泛使用，提供了有利的保证。     

BINELOCA 程序与广东岭澳核电站大破口失水事故分析

ＢＩＮＥＬＯＣＡ程序是在吸收国外先进大破口失水事故分析计算机程序的基础上，针对我国现有大破口失水事故分析程序的不足和工程应用方面的问题，采用了一些成熟的、新型的和当今国际公认的瞬态热工水力数学物理模型以及水和蒸汽性质参数计算公式改编而成的大破口失水事故分析程序。通过对广东岭澳核电站大破口失水事故的计算表明，ＢＩＮＥＬＯＣＡ程序计算的结果与法国计算的结果是一致的。     

蒸发冷却电机新冷却介质FF31L的实验研究

根据介质的热物理特性和公害性等性质初选了一种新冷却介质ＦＦ３１Ｌ。将初选的新介质ＦＦ３１Ｌ在自循环蒸发冷却实验模型上进行了实验，测取了不同负载下线棒沿长度上的温度分布，观察了自循环冷却情况。建立了介质传质特性研究的实验模型，进行了新介质传质特性的实验研究，得到了蒸汽品质和汽液二相流阻放大倍数的关系曲线以及蒸汽品质和汽液二相中汽占体积比之间的关系曲线。     

反应堆堆芯围筒结构热流固耦合热变形分析

针对反应堆堆芯围筒热流固耦合问题,采用三维有限元法研究堆芯围筒的热变形.考察ANSYS的三维实体热单元SOLID 70,三维实体单元SOLID 45,三维表面热效应单元SURF 152和三维热-流耦合管单元FLUID 116等单元类型的特点和实用性.建立堆芯围筒、吊篮和冷却剂的温度分析有限元模型：堆芯围筒和吊篮采用SOLID 70,结构表面与冷却剂的对流传热表面采用SURF152,堆芯围筒与吊篮之间冷却剂采用FLUID 116.采用SOLID 45建立堆芯围筒有限元模型,根据得到的堆芯围筒、吊篮和冷却剂的温度场结果分析堆芯围筒热变形.结果表明,在考虑堆芯围筒及吊篮固体和流体的交叉耦合的基础上,采用三维有限元法能比较客观地模拟反应堆堆芯处的复杂运行环境.     

Modelling of the mist formation in a segmented grinding wheel system

It has been found that using a segmented grinding wheel with a fluid chamber can significantly minimise the quantity of coolant while improving the ground surface integrity. The present investigation aims to explore the fluid flow mechanism in such a wheel system. To this end, the Weber theory for Newtonian jet instability was applied to quantitatively determine the contribution of coolant flow rate to mist and ligament modes. A semi-analytical model was then developed to predict the mist flow rate by taking into account both the grinding parameters and fluid properties. It was shown that the model prediction was in good agreement with experimental measurements. Because of the comprehensive integration of variables in the formulation, the model provides a good fundamental understanding of the mist formation and offers a practical guideline for the selection and use coolant in minimising the mist flow rate.     

Mechanism and laws of combustion of composite solid propellants with a coolant

The model of combustion of a composition consisting of a quasi-homogeneous composite propellant (matrix) and coolant particles is considered. The model is based on the leading role of exothermal decomposition of the matrix and on the cooling effect of the second component by virtue of transverse heat transfer between the components in the condensed and gas phases. Formulas for combustion characteristics (temperature, burning rate, its sensitivity to pressure, and initial temperature) are derived and analyzed. The calculated dependences of these characteristics on pressure, particle size, concentration, and thermal effects of decomposition of the components show that transitional regimes with a stronger dependence of the burning rate on pressure than that of the initial propellant are reached in a certain range of parameters. An algorithm is proposed, and a parametric identification of the model on the basis of experimental data is performed. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 6, pp. 51–60, November–December, 2007.     

氧化铝纳米流体在车用热交换器中的试验研究

研究纳米流体在车用热交换器中的强化传热效果,测试不同纳米粒子体积分数的氧化铝纳米流体在板翅式机油冷却器中的传热和流动特性,并与水、防冻液（乙二醇）及纳米流体基础液体进行对比.试验结果表明,在同一热交换器中,纳米流体的传热系数明显高于其他3种液体.当冷、热侧介质温度为90和120 ℃时,纳米粒子体积分数为5%的纳米流体的传热系数分别比水、乙二醇和基础液体提高6.52%、18.88%和24.62%;当冷、热侧介质温度为120和135 ℃时,体积分数为5%的纳米流体的传热系数比体积分数为1%的纳米流体提高104.72%.在试验条件下,热交换器的换热量随纳米粒子体积分数的增大而增大,但流动阻力并未明显增加,初步证明了纳米流体应用于车用热交换器的可行性.     

DSmT的主冷却剂泵并发故障融合方法分析

针对核电站主冷却剂泵故障特征微弱难以有效辨识及DST仅能解决在无高冲突辨识框架下的单一故障诊断等问题,提出一种基于DSmT决策级主冷却剂泵并发故障融合诊断模型．采用核主泵自由DSm模型和混合DSm模型对含有故障信息的多个独立证据源进行动态融合计算;分析核主泵DSmT故障特征信度赋值变化,确定主冷却剂泵故障(并发故障)诊断总决策. 结果表明, 将核仿真机采集TS、SS、VS和DS多源传感器数据直接对基本概率函数进行赋值,得出主冷却剂泵故障(并发故障)决策结果与实际工况相符,实例验证了所提方法的可行性、有效性及准确性．     

树脂砂轮研磨钢球专用磨削液的研制

本文针对钢球磨削液存在的问题，研究了反应时间、温度、搅拌速度、加料时的温度以及冷却方式等条件对磨削液性能的影响。适宜的工艺条件为聚乙二醇：邻苯二甲酸酐=10：1，反应温度110—130℃，搅拌速度500—650n／min，加入配料时温度70-80℃。该磨削液专门适用于树脂砂轮研磨钢球，可以解决树脂砂轮在磨削液中的腐烂问题，并有利于环境保护。