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多孔介质方法在池式快堆系统分析软件SAC-CFR三维钠池计算模型中的应用 总被引:1,自引:1,他引:0
为准确分析池式快堆热钠池内的热工水力学特性,在已开发出的用于池式快堆系统分析的钠池三维计算模型的基础上,应用多孔介质方法建立钠池内中间热交换器、主泵、事故热交换器及屏蔽柱模型,完成了含有多孔介质模型和复杂几何边界的钠池三维计算模型开发。将该模型嵌入池式快堆系统分析软件SAC-CFR后,分析了中国实验快堆在稳态运行和紧急停堆工况下钠池内的流场分布,初步证明了所采用的多孔介质模型的合理性,为下一步非能动余热排出系统模型的开发做准备。 相似文献
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中国实验快堆(CEFR)作为中国第一座钠冷快中子反应堆,蒸汽发生器作为分隔二回路和三回路器的重要设备,其运行的稳定性、可用性对于中国实验快堆的稳定运行具有重要意义。中国实验快堆蒸汽发生器首次进水试验验证了蒸汽发生器具备了在低功率下运行的完整性、可用性、稳定性和良好的传热性能。根据记录数据就钠侧和水侧的对流换热进行了热平衡校核计算,计算结果表明了本次试验钠侧和水侧换热量平衡,计算结果表明在低流量、低钠温的运行工况下水侧为主要换热热阻,该热阻值可以由格尼林斯基(Gnielinski)公式确定。 相似文献
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安全棒及其驱动机构是钠冷快堆中的紧急停堆系统,其落棒时间一直是钠冷快堆安全设计关注的重点之一。本文利用一维水力管网方法对中国实验快堆中的安全棒系统落棒过程开展了详细的建模和分析,得到了安全棒在落棒过程中的位移、速度、加速度与时间的关系,并与中国实验快堆调试试验结果进行了对比。同时,基于该方法开展了中国实验快堆安全棒落棒时间与冷却剂流量及温度的敏感性分析及研究。 相似文献
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This study analyzed the rate of loading (ROL) phenomenon, which is generated during the operation of a motor operated valve (MOV) under fluid pressure conditions. ROL is one of the most important parameters for an MOV performance evaluation. This paper includes the analysis results for the characteristics of ROL and the effect of fluid pressure on the ROL. Dynamic and static test were performed to analyze the ROL effect for flexible wedge gate valve. The result of this analysis confirmed that the ROL is generated under fluid pressure condition and that the ROL value under high differential pressure condition appeared to be higher than under low differential pressure condition. According to the test results of multiple valves, the ROL appeared to become higher, as the differential pressure increased, and under the high differential pressure condition, it accounted for approximately 17.6% of the thrust loss. In addition, the ROL effect was negligible in valves with a low differential pressure (below 1100 kPa). 相似文献
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由于核电厂严重事故的恶劣工况,在卸压过程中严重事故卸压阀门可能会经历阀门无法承受的高温瞬态而导致不可用。本文在可能导致高压熔堆的事故序列中筛选出具有一定的包络性并包含各种典型严重事故现象的典型严重事故序列。针对该事故序列考虑严重事故管理中的开阀时间范围开展了高温瞬态计算,并针对重要的影响因素阀门开启时刻的稳压器水位开展分析。最终确定了百万千瓦级核电厂具备典型性及一定包络性的严重事故卸压阀工作条件,并得到了阀门开启前后阀门可能经历的最高流体温度及流体温度变化曲线,为严重事故卸压阀门的设备鉴定及功能应用提供了重要基础。 相似文献
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The HCPB concept has been a European DEMO reference concept for nearly one decade. Detailed thermal-hydraulic study on the control behavior of the whole system is one of the important parts of this development. The thermal-hydraulic effect of the TBM-combined cooling circuit during a cyclic operation in ITER has been studied using the system code RELAP5. The RELAP5 is based on an one-dimensional, transient two-fluid model for the flow of a two-phase steam-water mixture that can contain noncondensable components like Helium. The RELAP5-models are modified to take the cyclic operation of the circulator, heat exchanger, bypass, valves etc in to account. A sequence of operational phases is investigated, starting from the cold state through the heating phase that brings the system to a stand-by condition, followed by typical power cycles applied in ITER. The results show that the implemented control mechanisms keep the inlet temperature to the TBM and the total mass flow rate at the required values through all phases. 相似文献
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Horst Nagel 《Nuclear Engineering and Design》1986,96(2-3)
The flow induced valve operation is calculated for single and two-phase flow conditions by the fluiddynamic computer code DYVRO and results are compared to experimental data. The analysis show that the operational behaviour of the valves is not only dependent on the condition of the induced flow, but also the pipe flow can cause a feedback as a result of the induced pressure waves. For the calculation of pressure wave propagation in pipes of which the operation of flow induced valves has a considerable influence it is therefore necessary to have a coupled analysis of the pressure wave propagation and the operational behaviour of the valves.The analyses of the fast transient transfer from steam to two-phase flow show a good agreement with experimental data. Hence even these very high loads on pipes resulting from such fluiddynamic transients can be calculated realistically. 相似文献
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Sodium fire is a typical accident of sodium-cooled fast reactor. Simulation of sodium fire accident scenario by software is a powerful tool for risk assessment of sodium fire accident. In this paper, the conventional fire three-dimensional computational fluid dynamics software FDS was used as a platform to add a sodium fire combustion model, including combustion heat model, combustion rate model, spray liquid sodium particle size distribution model, etc., and complete the development of sodium fire scenario modeling analysis program. And through the comparison with SPHINCS sodium fire test and calculation results, the feasibility of the method and development plan was verified. The research results of this paper can provide the research basis and experience reference for the development of the subsequent sodium fire simulation program. 相似文献
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钠火是钠冷快堆的典型事故,钠火事故情景计算机模拟仿真是对钠火事故风险评价的有力工具。本文以常规火灾三维计算流体力学软件FDS为平台,增加钠火燃烧模型,包括燃烧热模型、燃烧速率模型、喷射液钠粒径分布模型等,完成了钠火情景模型的开发,并通过与SPHINCS钠火试验和计算结果的温度分布与氧气含量对比,验证了模拟技术和模型开发方案的可行性。本文的研究成果能为后续钠火仿真模拟程序的开发提供研究基础和经验参考。 相似文献
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Y.W. Chang 《Nuclear Engineering and Design》1984,80(1):99-104
The closing valves are the main part of time in stand-by state. It is characteristic that the reliability of the valves decreases during stand-by time. Therefore the valves are tested periodically in order to check their condition. On the other hand, the testing may cause failures and thus decrease the availability of valves. Through a proper choice of test internal these competing factors can be balanced against each other. Optimum tests interval of closing valves is considered with the aid of simple unavailability models and using reliability data collected from Finnish BWR plants. 相似文献