Abstract This paper is focused on overcoming reactor shutdown malfunction and diagnostics due to poor cooling and water drop level within a pressurized water reactor. So the temperature coupling analysis between the heat exchanger (HEX) and the U-tube steam generator (UTSG) is inspected under changes of primary and secondary water temperature. This coupling allows the removal of heat from the UTSG via the HEX. For the UTSG, implicit and explicit solutions for analysis and evaluation of UTSG characteristics are conducted. Scarce explicit models describing the behaviors of the UTSG are available. This analytical framework is proposed to control the water/steam flow within the UTSG of a nuclear power reactor (NPR). Exact performances for temperatures of metal tube temperature and primary water entering and exiting from the tube are derived. There is no one implicit model that can describe the performance characteristics of heat transfer within the UTSG. So a novel simulator declaring the operational behavior of the UTSG in an NPR has been built. This simulator of the UTSG provides exact handling of the UTSG performance characteristics. For the HEX, the exact handling of the HEX including boundary temperature and the primary and secondary interface temperatures are proposed. Three different models are implemented (combinational, steady state, and integral). The possibility of realizing higher steam quality is established through block diagram programming models. Compared to literature results, the built models are validated with high agreement. As a final conclusion, the proposed analyses allow the control of steam generation and flow. The introduced results compensate for the necessity of expensive and complicated controllers within the HEX and UTSG through parameter variation. Accordingly, the performance of the NPR is enhanced.

中文翻译：

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核蒸汽发生器与压水堆内换热器温度耦合分析

摘要 本文的重点是克服由于压水反应堆内冷却不良和水位下降而导致的反应堆停堆故障和诊断。因此，在一次和二次水温变化的情况下检查换热器（HEX）和U型管蒸汽发生器（UTSG）之间的温度耦合分析。这种耦合允许通过 HEX 从 UTSG 中去除热量。对于 UTSG，进行了用于分析和评估 UTSG 特性的隐式和显式解决方案。很少有描述 UTSG 行为的显式模型可用。该分析框架旨在控制核动力反应堆 (NPR) UTSG 内的水/蒸汽流。导出了金属管温度和进出管的初级水温度的精确性能。没有一种隐式模型可以描述 UTSG 内的传热性能特征。因此，已经构建了一个新的模拟器，用于声明 NPR 中 UTSG 的操作行为。该 UTSG 模拟器提供了对 UTSG 性能特征的精确处理。对于 HEX，提出了对 HEX 的精确处理，包括边界温度和主要和次要界面温度。实现了三种不同的模型（组合、稳态和积分）。通过框图编程模型建立了实现更高蒸汽质量的可能性。与文献结果相比，构建的模型得到了高度一致的验证。作为最后的结论，建议的分析允许控制蒸汽的产生和流量。引入的结果通过参数变化补偿了 HEX 和 UTSG 中昂贵且复杂的控制器的必要性。因此，增强了NPR的性能。