低压汽轮机电液调节系统内部流道阻力研究

Research of Internal Flow Resistance of Low-Pressure Steam Turbine Electro-Hydraulic Regulating System

低压汽轮机电液调节系统中的保安集成块内部流道阻力直接影响到先导油压的动态泄压品质。通过CFD仿真分析了保安集成块内部的三种π形流道模块单元、T形正交与非正交流道模块单元以及直角交叉兼具突扩特征的流道模块单元的流动机制,对比各自的流量-压力损失特性,提出一种简易预测集成块复杂流道阻力的方法。结果表明:在直角转弯流道中,适当增大液流流动的曲率半径,可减小压力损失;同等流量下,直角交叉兼突扩特征的流道模块单元压力损失最大。

The dynamic pressure relief quality of the pilot oil pressure directly depends on the resistance of the internal flow channel of the security manifold in the electro-hydraulic regulating system of low-pressure steam turbine.The flow field characteristics of threeπchannel module units,T-type orthogonal and non-orthogonal channel module units and right angle crossing and sudden expansion characteristics channel module unit in security manifold were analyzed by CFD simulation,and flow-pressure loss characteristics were compared,a simple method for predicting the complex channel resistance in manifold block was proposed.It is shown that the pressure loss can be reduced by appropriately increasing the curvature radius of the liquid flow in the right angle turning channel;under the same flow rate,the pressure loss of the channel module unit with the characteristics of right angle crossing and sudden expansion is the largest.