节点文献
核电站冷却剂主泵机械密封的流固热耦合研究
Research on Fluid-thermal-structural Coupling of Mechanical Seals in Reactor Coolant Pumps in Nuclear Power Station
【作者】 魏琳宗；
【导师】 刘向锋；
【作者基本信息】 清华大学 ， 机械工程， 2010， 硕士
【摘要】 本文研究了一种应用于核电站冷却剂主泵的流体静压式机械密封,该类机械密封具有收敛的密封间隙,正常工作时,动静环之间形成完全的流体膜,通过收敛间隙的泄漏量被严格控制在一定范围内。同时,流体膜可以为摩擦副提供润滑和冷却,保证密封环可以长时间工作而不磨损,具有良好的稳定性。本文建立了密封间隙流场的计算模型,在密封闭合力一定的条件下,研究了密封端面结构参数对密封性能的影响,对密封端面结构参数进行了优化设计。研究结果表明,密封端面锥角和转折半径均对密封性能有显著影响。基于有限元分析方法,选用工程软件ANSYS,以密封组件为对象,研究了密封间隙的流场、温度分布、弹性变形和热变形。同时通过流场计算和密封组件热弹变形计算的自动迭代,实现了密封的流固热耦合分析。本文使用的流固热耦合模型综合考虑了密封组件之间的接触摩擦、预紧作用、热传导作用等,能够真实反映流体和密封结构之间的相互影响。与已有研究和文献的实验结果比较,具有较好的一致性。研究了密封端面结构参数、预紧力和转速等操作参数和压力、温度等环境参数对密封性能的影响,可以为静压式机械密封结构及操作参数的设计提供理论参考和依据。
【Abstract】 A kind of hydrostatic mechanical seal with convergent gap used in reactor coolant pump in nuclear power station is introduced. When working normally, complete fluid film can be formed between the seal rings. As a result, the leakage rate through the gap is strictly controlled within a certain range. Meanwhile, the fluid film can provide lubrication and cooling for the friction pair, which guarantee that the seal rings can work for long without abrasion.A theoretical analysis model is developed for the flow field in the seal gap. Using the finite element method, under a certain closing force, the effect of sealing surface structure parameters on sealing performance is analyzed and the optimization of structure parameters is carried. Results show that the transition radius and cone angle have significant effect on the sealing performance.Based on the FEM method and by using the software ANSYS, the flow field,temperature distribution, elastic deformation and thermal deformation of seal components is got. The fluid-thermal-structural coupling is achieved by automatic iterative between the flow field calculation and the seal component calculation. This model allows for the effect of contact, preload and thermal conduction between seal components, and can accurately reflect the interaction between the fluid and seal components.The effect of sealing surface structure parameters; the preload and rotation speed; the pressure and temperature on sealing performance is analyzed, which can provide theoretical reference and foundation for the design of structural and operational parameters for hydrostatic seals.