核电站用波形板汽水分离器的数值模拟和实验的研究.pdfVIP

摘 要 波形板汽水分离器是压水堆核电站立式自然循环蒸汽发生器汽水分离系统中关 键部件之一。作为该系统最后一级分离器，它在核电站中的地位随着核电站单堆功 率的增加而与日俱增。为了保证在较高的蒸汽负荷、压力和循环倍率下仍能提供品 质合格的蒸汽，对波形板汽水分离的性能也提出了更高的要求。 二次液滴在波形板汽水分离过程中的产生会严重影响分离装置的效率，这一点在 学术界已经成为共识。然而由于波形板内物理现象的复杂性和机理的模糊性，不同 的学者对于二次液滴产生机理的研究存在争议。本文在参考前人所提出的各种机理 后，对二次液滴的产生原因进行了重新整合与归类并给出了相对比较全面的机理分 析。并在前人的基础上建立了波形板汽水分离器内液滴和气流两相的数学模型，对 液滴相建立了基于拉格朗日描述的质量、能量和动量守恒方程。 此外，对已经完成的冷态实验数据进行了处理，并将不同类型波形板间的分离效 率的优劣进行了对比与定性分析并最终将波形板的分离效率通过无量纲数进行了拟 合而达到指导波形板设计的目的。在前述数学模型的基础上，除了对已有不同种类 的波形板汽水分离的过程进行了热态条件下的数值模拟，还对改造后的双钩波形板 进行了模拟。 最后，本文对波形板的后续研究工作提出了建议。 关键词：波形板汽水分离器，二次液滴，分离效率，无量纲拟合，数值模拟 I ABSTRACT Corrugated plate is one of the most fundamental components of the natural circulation evaporator in PWR(pressurized water reactor) nuclear power plant. As the last stage of the steam separation system, corrugated plate are playing more and more significant role in nuclear power plant as a result of the increasing of power in one nuclear power plant. In order to guarantee the quality of steam even in the condition of higher load of steam, pressure and circulation rate, the criteria for the performance of corrugated plate is gradually strict. Academicians have already come to agreement that the secondary droplet in the process of separation will undoubtedly reduce separation efficiency. However, due to the complexity of the physics phenomena and obscurity of the mechanism in the process of separation in the two-phase flow, there are sorts of different theories about the generation of secondary droplet. Diverse theories which were based on former researchers’ work were classified and relatively general mechanism of the generation of secondary droplet was provided in this thesis. Meanwhile, we build th