核主泵2号密封变形机理及泄漏特性数值研究

Deformation Mechanism and Leakage Characteristic Research of Second Mechanical Seals for Reactor Coolant Pumps

核主泵2号密封在事故工况下,需要承受一回路高压,由于缺乏2号密封在承受高压条件下的密封机理研究,严重制约2号密封承受高压时的可靠性分析和评价。依托CPR1000核电机组100型核主泵2号密封,提出一种流固耦合分析数值模型并通过台架试验验证,系统阐述了核主泵2号密封承受高压时由摩擦面密封向流体静压型密封的转变机理,并研究了动环锥角、泄漏量随压差增加的变化规律。通过数值研究,发现2号密封锥角和泄漏量在5 MPa压差左右出现拐点,动环锥角最大约为0.05°,随着压差进一步增加,动环锥角基本保持不变,泄漏量则随压差呈现近似线性上升。

The reliability analysis and evaluation of high pressure operating conditions of the second mechanical seals in reactor coolant pumps could not to be intensively investigated for the lack of seal mechanism study.In this study,a FSI(Fluid-Structure-Interaction) model was built and verified based on the 100-type reactor coolant pumps of CPR1000 units to investigate the seal mechanisms from the face seal to the hydro-static mechanical seal and change rules of the rotation seal ring cone angle and leakage rate.Based on the investigation of the high pressure operating conditions,the inflection point was found at 5 MPa and maximum cone angle of rotation seal ring was 0.05°.The cone angle of rotation seal ring tends to be stable and the leakage rate tends to be linear with further pressure enhancement.