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控制棒驱动机构步进运动由钩爪组件的提升衔铁在竖直方向上升和下降的交替运动实现。通过对控制棒驱动机构步进运动进行分解,采用有限元方法建立电路-磁路-机械运动耦合的动态计算模型,对控制棒驱动机构步进运动过程中电磁力、电流、位移和时间关系进行研究,得到步进运动的提升时间、下降时间、衔铁吸合时电流和电磁力等运动特性参数。 相似文献
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控制棒驱动机构运动过程是电磁场-流场-运动场相互耦合的复杂动态过程,无法通过静态方法或单项技术进行准确的计算。使用Magnet软件、Fluent软件和Adams软件进行了电磁仿真分析、流场分析和多体动力学分析的耦合计算。综合考虑了重力、电磁力、水阻力和弹簧力在控制棒驱动机构步跃过程中的作用,定量计算了电磁力、水阻力、运动件位移与速度等运动特性,以及步跃载荷。通过与试验值对比,计算得到的移动磁极吸合时间、临界吸合电流和步跃载荷值与试验值较为吻合,证明了控制棒驱动机构运动过程的联合仿真分析是一种有效的动态分析方法。 相似文献
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在中国先进研究堆(CARR)调试阶段,发现其控制棒驱动机构在转向过程中存在驱动线圈与控制棒运动不同步的现象。为掌握控制棒驱动机构的转向性能参数,在静水条件下进行了控制棒驱动机构转向性能测试试验。试验表明:驱动线圈与控制棒运动不同步是磁悬浮式控制棒驱动机构的固有特性;棒位、棒速和驱动线圈通电电流大小等因素对静水条件下转向性能影响不大,且四组驱动机构静水条件下转向性能具有一致性。 相似文献
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In sodium-cooled fast reactors, control rods are commonly used to compensate for the excess reactivity and shut down the reactor. The traditional sodium-cooled fast reactor design consists of the safety rod, shim rod and regulating rod. The 10B enrichment of the shim rods is relatively higher, which unavoidably increases the burnup, the heat generation and the power peak factor of the fuel assemblies around the shim rods. To solve this issue, the segment design of control rods was proposed. Compared with traditional design, the new design can significantly reduce the heat generation by about 30 percent and burnup of control rods by about 50 percent, as well as improve the power peak factor of the fuel assemblies around the shim rods. The replacement cycle of the control rods can be extended by time. 相似文献
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控制棒水压驱动系统是清华大学为低温核供热堆发明的新型的内置式控制棒驱动技术,控制棒水力减速部件是水压驱动系统的关键部件之一,通过其对控制棒落棒过程进行减速,在保证落棒时间的前提下,降低控制棒快速落棒过程的冲击力。分析了水力减速部件组成和工作原理,确定了水力减速箱侧壁开孔方案,完成了不同开孔方案工况下控制棒水压驱动系统冷态落棒减速性能实验,在实验结果的基础上对比和分析了不同方案下的落棒减速机理和落棒过程特征参数随开孔方案的变化规律。分析结果表明:随开孔面积的增大,落棒时间逐渐减小,落棒峰值速度逐渐增大。在开孔面积大于0.004 m~2时,随开孔面积的增大,落棒峰值速度增大过程趋于平缓,落棒稳定速度和落棒延迟时间变化不大,控制棒触碰碟簧速度缓慢增大。实验研究成果为控制棒水压驱动系统落棒减速部件的理论建模和设计优化提供了基础。 相似文献
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控制棒水压驱动系统是清华大学为低温核供热堆研制的新型内置式控制棒驱动技术,控制棒水力减速部件是水压驱动系统的关键部件之一,在保证落棒时间的前提下,通过其对落棒过程进行减速,降低控制棒快速落棒过程的冲击力,避免控制棒十字翼的变形和损坏。本文分析了控制棒水压驱动系统落棒减速机理,利用CFD软件FLUENT对驱动系统水力减速箱流道进行了三维流场数值分析,并分析了对应不同落棒位置水力减速箱流道在不同边界条件下的流场分布特性。在流场分析结果的基础上计算得到了水力减速箱侧壁孔流道和底部缓冲腔流道流量系数随落棒位移的变化,将该结果与驱动系统落棒减速理论模型联立,获得了控制棒落棒位移曲线,理论计算结果同冷态落棒性能实验结果符合得很好,从而验证了流场分析结果的正确性,在此基础上分析了落棒过程减速箱内外差压和落棒速度与水力减速箱流量系数的关系,为控制棒水压驱动系统落棒减速部件的设计和优化提供了指导。 相似文献
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The dropping time and profile of control rods are important parameters during the safety evaluation of nuclear power plants. CFD method and dynamic mesh were used to study the dropping profile of the control rod and flow evolution. The changes of displacement, velocity and acceleration versus time during the dropping of the control rod are obtained. Meanwhile, the effect of the deformation of the control rod and channel on the control rod dropping is evaluated. The results of the work are of help to the design and optimization of the structure of control rods. 相似文献
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介绍了5MW核供热堆水力驱动控制棒逻辑控制系统的功能与特点,以及提高系统可用性和安全性的技术措施。本系统与控制棒水力传动机械相匹配,构成完整的控制系统,用来完成堆的反应性控制。其性能稳定可靠、抗干扰能力强。成功地用于5MW供热堆,并满足其运行的要求。 相似文献
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《Journal of Nuclear Science and Technology》2012,49(12):1120-1129
ABSTRACTNeutronics analysis was conducted for a proposed megawatt-class gas cooled space nuclear reactor design. The reactor design has a high operating temperature of up to 1500 K. Annular UO2 fuel rods were used to reduce the central temperature of the fuel. The thermal power is 2.3 MWt and is converted into electric power by a direct Brayton cycle. The control rods were arranged in different configurations and were analyzed in order to evaluate the influence on the reactor design in different scenarios. The calculation results reveal that the control rods arrangements have influences on the begin-of-life (BOL) excess reactivity and the shutdown reactivity. The distribution of control rods affects the neutron economy and leakage in the fuel region, consequently affecting the reactivity. It is also known that the reactivity in flooding scenarios are not sensitive to different control rod arrangements. Meanwhile, according to calculation results, the proposed reactor design has enough shutdown reactivity margin which will allow for flexible control strategy. Further analysis is still needed for more detailed and accurate parameters of the reactor design. 相似文献
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Ho-Cheol Shin 《Journal of Nuclear Science and Technology》2013,50(3):369-375
This study describes a multi-resolution analysis (MRA) to determine the onset and end drop times of control rods. The measurement test of the drop times of control rods is normally performed during the start-up test of each reactor cycle since it is a crucial safety function to guarantee the reactor safe shutdown. The MRA with wavelet transform is particularly useful in analyzing the onset transients of rod drop as a means of capturing the unique attributes of such signals in an efficient way. This approach also allows the automated determination of rod drop time which reduces the uncertainty induced by ad hoc heuristic approaches. The test signal is generated by adding the random noise measured from real rod drop tests subtracting the wavelet-filtered noise free signal from the noisy signal leaving the noise. The signal is similar to both high sharp spikes noise and sine wave noise from the real voltage trace generated during the rod drop test. The effectiveness of the method is demonstrated by the MRA process. 相似文献
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介绍了三维带控制棒计算反应性温度系数的计算方法,对于200MW供热堆,在不同棒位下作了三维反应性温度系数的计算,结果表明,慢化剂温度系数的大小和控制棒插入的深度有一定关系。以运行工况临界棒位下的慢化剂温度系数为参考,对二维计算结果作了分析,结果表明第二维无控制棒计算是保守的近似。 相似文献