高温熔融液滴破碎特性实验研究

对高温熔融液滴在水中的破碎特性进行了实验研究,重点考察和分析了液滴材料的物理化学性质、熔化潜热和熔融液“粘糊状区域”(Mushy Zone)等因素对液滴破碎过程的影响。用共晶和非共晶的铅(Pb)-铋(Bi)合金作为液滴材料,用水作冷却剂,完成了约10个系列的实验工况．分别测量了液滴破碎后碎片的累积质量分布和质量平均尺寸。根据实验结果探讨了液滴材料的焓、熔化潜热、粘性等因素影响液滴变形与破碎过程的规律。     

音速浸没射流气羽特性实验研究

以直径10 mm喷管为研究对象,针对入口压力为0.2～0.8 MPa的饱和蒸汽在20～60 ℃过冷水中气羽特性进行了实验研究。结果表明,蒸汽气羽长度主要受蒸汽质量流速和水温影响,随蒸汽质量流速及水温的升高,气羽长度增加。同时根据实验结果,在理论推导的基础上给出了计算气羽无量纲穿透长度及换热系数的实验关联式。气羽长度预测值与实验值相对误差在±15%以内,换热系数预测值与实验值在椭圆形气羽区相对误差在±12%以内。     

调频对ICRH天线系统单铁氧体阻抗匹配效果的研究

采用传输线理论分析了离子回旋共振加热(Ion Cyclotron Resonance Heating,ICRH)天线耦合阻抗变化时(2～8Ω),频率反馈控制对ICRH天线系统单铁氧体调谐器阻抗匹配效果的影响.模拟结果表明:在一定条件下,优化设计铁氧体长度及天线与单铁氧体调谐器之间的机械长度(归一化长度约0.540),结...     

先进安注箱阻尼器压降特性实验研究

通过开展先进安注箱阻尼器压降特性实验,获得了阻尼器两种不同形式的压降特性,研究了不同几何参数对压降系数的影响规律,并且拟合了压降系数关系式。结果表明：在实验参数范围内,漩涡压降系数随雷诺数增加而逐渐增大,交混压降系数随大/小管流量比的增加,先快速减小而后缓慢增加。小管宽度和阻尼器直径对漩涡压降系数有一定程度影响,大小管夹角、阻尼器直径和大管宽度对交混压降系数有影响,小管宽度对交混压降系数影响不明显。漩涡压降系数关系式预测值与实验值偏差在±10%以内,交混压降系数关系式预测值与实验值偏差较大。     

小型核电源传热及热电特性实验研究

针对无人水下航行器（UUV）续航能力差这一缺点,结合核动力UUV中的结合静默式温差发电热管反应堆技术,建立非核电加热实验台架,进行启动实验,验证静默式温差发电热管堆技术的技术可行性。实验结果表明:实验装置系统启动过程顺利,启动后等温性良好;温差发电器件热电性能良好,发电效率可达6.8%。该实验装置作为国内首个基于温差发电及高温热管传热的电加热实验台架,其实验数据可为静默式温差发电热管反应堆进一步设计和应用提供参考。      

电磁脉冲在高空电离层等离子体中传输特性研究

高层大气在太阳紫外线、X射线和高能粒子的作用下,部分中性分子电离成离子和自由电子,形成等离子体区域即电离层。为了研究电离层对电磁脉冲传输的影响,本文使用基于时域有限差分法的全波三维电磁场模拟仿真软件(XFDTD),按照等离子体设备参数建立电磁脉冲传播模型,分析电磁脉冲穿过等离子体前后的时频特性,并与已有的试验结果进行了对比,初步得出等离子体对电磁脉冲具有展宽以及衰减的影响。     

简单通道内超临界水传热特性实验研究

针对各国超临界水冷堆燃料组件设计方案,选取圆管、圆环形通道、方环形通道3种具有热工水力代表性的简单通道,开展超临界条件下水工质的传热特性实验研究。实验结果表明,热流密度、质量流速和压力3种热工参数对不同简单通道传热特性的影响趋势基本一致;在相同质量流速和压力下,换热系数在靠近拟临界温度处存在峰值,且随热流密度的增大而减小;在相同热流密度和压力下,相同主流体焓处对应的换热系数随着质量流速增加而增加;压力对超临界水传热特性影响较弱,仅在拟临界区域内换热系数峰值稍有不同;实验中出现了拟临界区域的传热恶化现象,传热恶化发生时壁温出现局部峰值。     

安全壳换热特性单项分离效应实验研究

安全壳的冷凝换热能力是影响非能动安全系统导出堆芯余热的关键因素之一。针对ACP100K模块化小型堆的非能动安全壳冷却系统开展了安全壳换热特性单项分离效应实验研究。采用冷却剂能量平衡法测量热流密度,主要研究了主流蒸气温度、主流蒸气与冷凝壁面温差、主流蒸气质量流量、壁面倾斜角度和不可凝结气体对冷凝换热系数的影响。基于实验数据拟合得到了主流蒸气温度对冷凝换热系数的关系式。     

脉冲信号沿长电缆传输的研究

本文介绍脉冲在同轴电缆中传输的数学表达式和几种工程上实用的例子及其特点。并提出了系统消除干扰的几种办法。     

控制棒新型电磁驱动机构动态特性实验研究

介绍了一种全新的控制棒驱动机构方案—可动线圈电磁铁控制棒驱动机构 ,它将应用于中国先进研究堆上。该研究给出了动态位移实验曲线以及位移修正曲线。实验证明该机构运行稳定 ,没有任何抖动 ,各状态之间转换平稳 ,定位精度高 ,动态负载能力强 ,采用间接测量棒位时需要进行位移修正 ,位移修正值与电流和载荷有关     

快速电流脉冲发生器的设计

为调节合肥同步辐射光源（HLS）时间分辨站的同步光脉冲间隔,需要产生具有快速上升、下降沿的脉冲磁场,且脉冲宽度小、顶部平坦。本工作利用脉冲成形技术设计电流脉冲发生器,以产生这种快速电流脉冲,并给出了实验结果。     

双电缆系统电流耦合效应数值计算

介绍了利用电缆耦合模型,对两种电缆组成的电缆系统带负载情况下的干扰耦合进行了计算,并与实验数据作了对比,验证了计算模型的正确性。     

Study on Propagation Characteristics of Plasma Surface Wave in Medium Tube

Axial propagation characteristics of the axisymmetric surface wave along the plasma in the medium tube were studied. The expressions of electromagnetic field inside and outside the medium tube were deduced. Also, the impacts of several factors, such as plasma density, signal frequency, inner radius of medium tube, collision frequency, etc., on plasma surface wave propa- gation were numerically simulated. The results show that, the properties of plasma with higher density and lower gas pressure are closer to those of metal conductor. Furthermore, larger radius of medium tube and lower signal frequency are better for surface wave propagation. However, the effect of collision frequency is not obvious. The optimized experimental parameters can be chosen as the plasma density of about 10^17 m^-3 and the medium radius between 11 mm and 19 mm.     

Effect of High-Frequency Electric Field on Propagation of Electrostatic Wave in a Non-Uniform Relativistic Plasma Waveguide

The effect of a high frequency （HF） electric field on the propagation of electrostatic wave in a 2D non-uniform relativistic plasma waveguide is investigated. A variable separation method is applied to the two-fluid plasma model. An analytical study of the reflection of electrostatic wave propagation along a magnetized non-uniform relativistic plasma slab subjected to an intense HF electric field is presented and compared with the case of a non relativistic plasma. It is found that, when the frequency of the incident wave is close to the relativistic electron plasma frequency, the plasma is less reflective due to the presence of both an HF field and the effect of relativistic electrons. On the other hand, for a low-frequency incident wave the reflection coefficient is directly proportional to the amplitude of the HF field. Also, it is shown that the relativistic electron plasma leads to a decrease in the value of reflection coefficient in comparison with the case of the non relativistic plasma.     

垂直上升管内密度波不稳定性的研究

在低压自然循环水回路上，对垂直上升管内两相流动密度波不稳定性进行了实验研究，实半记录了不同工况下的脉动曲线，用多元线性回归这实验数据进行拟合，得出一个低压两相自然循环密度波的稳定性判据准则式，实验参数范围为，系统压力Ｐ＝０．２１～１．７５ＭＰａ，质量流速Ｇ＝３４５～１９４７ｋｇ／ｍ＾２．ｓ，进口对冷度△Ｔｓｕｂ＝６～６０℃，加热功率Ｑ＝２．３～２４ｋＷ。     

Study on the Mathematical Model of Dielectric Recovery Characteristics in High Voltage SF6 Circuit Breaker

According to the stream theory,this paper proposes a mathematical model of the dielectric recovery characteristic based on the two-temperature ionization equilibrium equation.Taking the dynamic variation of charged particle's ionization and attachment into account,this model can be used in collaboration with the Coulomb collision model,which gives the relationship of the heavy particle temperature and electron temperature to calculate the electron density and temperature under different pressure and electric field conditions,so as to deliver the breakdown electric field strength under different pressure conditions.Meanwhile an experiment loop of the circuit breaker has been built to measure the breakdown voltage.It is shown that calculated results are in conformity with experiment results on the whole while results based on the stream criterion are larger than experiment results.This indicates that the mathematical model proposed here is more accurate for calculating the dielectric recovery characteristic,it is derived from the stream model with some improvement and refinement and has great significance for increasing the simulation accuracy of circuit breaker's interruption characteristic.     

超临界水氧化处理核电站废阴离子交换树脂研究

在间歇式超临界水氧化(SCWO)设备中,对粉碎处理后的阴离子交换树脂水悬浮液在超临界条件下进行了氧化降解处理。实验研究了反应温度、反应压力、反应时间、过氧系数对COD去除率的影响,同时考察了催化剂种类、反应压力和反应温度对氨氮去除率的影响。通过正交试验,得到主要因素对处理效果影响的显著程度排序为:反应温度>反应压力>反应时间>过氧系数。结果表明:在反应温度540 ℃、反应压力26 MPa、反应时间8 min、过氧系数3的条件下,COD去除率为99.65%。针对阴离子树脂中NH₃-N含量高难以去除的问题,选用不同的催化剂CuSO₄、MnO₂、CeO₂添加到反应体系中,结果表明对NH₃-N的氧化效果顺序为CuSO₄>CeO₂>MnO₂,对NH₃-N的最高降解率达到96.53%。     

Experimental Study on Temperature Coefficient of Reactivity in Light-Water-Moderated and Heavy-Water-Reflected Cylindrical Core Loaded with Highly-Enriched-Uranium or Medium-Enriched-Uranium Fuel

By using the Kyoto University Critical Assembly (KUCA), a series of critical experiments was performed to measure the temperature coefficient of reactivity in a light-water-moderated and heavy-water-reflected cylindrical core loaded with highly-enriched-uranium (HEU) or medium- enriched-uranium (MEU) fuel. The measurement was performed for the approximately 20 to 70°C range to examine the effects of the size of light-water region in a heterogeneous multi- region type core, the reduced ²³⁵U enrichment, and the existence of boron burnable poison (BP) on this quantity by using six types of core configurations. In all the six types of cores, there were large light-water regions at the center of core and between the outer fuel region and the heavy-water reflector region, and it was found that these light-water regions caused a remarkably positive effect on the temperature coefficient of reactivity. In the present study, the temperature coefficients of the MEU core and the core without BP were more positive than those of the HEU core and the core with BP, respectively. The size of light-water region had a larger effect on the temperature coefficient rather than the reduced ²³⁵U enrichment and the existence of BP. The negative temperature coefficient would be realized by reducing the thickness of light-water layer existed in the core.     

蒸汽爆炸粗混合阶段冷液中高温球传热阻力耦合特性的实验研究

采用蒸发电力模型,设计了高温颗粒同水相互作用的实验装置,进行了一系列单个,多个粒子在不同温度,不同入水初速度和不同冷液过冷度情况下的系列阻力实验,初步实验分析表明,高温颗粒在刚刚穿过冷液表面的下沉速度明显低于冷态颗粒的速度,实验值与蒸发曳力模型计算值符合较好.