核电站高压管道冲蚀、沉积问题的数值分析

Numerical Analysis of Erosion and Deposition Problems of High Pressure Pipes in Nuclear Power Plants

为了研究核电站高压管道中氧化物粒子对管道的冲蚀、沉积现象,深入探究粒子对管道的冲蚀、沉积机理,本文利用计算流体力学软件,以90°弯管和变径管这两种具有代表性的特征管段为研究对象,根据核电站高压管道运行时的实际粒子数据,计算并分析了介质流动特性及对管壁的冲蚀、沉积特性。结果表明,固体粒子对管道冲蚀最严重的部位位于90°弯管轴向角θ=30°～60°外壁处,变径管入口处和变径处;粒子沉积热点与冲蚀最严重部位基本吻合。因此,在核电站大修期间,应着重对以上部位进行检测、维修与防护,以保证核电站安全稳定运行。

In order to study the erosion and deposition of oxide particles in the high-pressure pipeline of nuclear power plants and explore the mechanism of erosion deposition, in this paper, the computational fluid dynamics software is used to study the two characteristic pipe segments of 90° elbow and reducer. The flow characteristics of fluid, erosion and deposition characteristics of the wall are calculated and analyzed according to the actual particle data of the high-pressure pipeline of the nuclear power plant.The results show that the most severe parts of erosion are located at axial angle θ=30°~60° of the outer wall of the 90° elbow, entrance and the reducing portion of the reducer. What’s more, the most severe part of the deposit coincides with the most severe part of the erosion. Therefore, during the overhaul of nuclear power plants, the above parts should be focused on testing and maintenance to ensure the safe and stable operation of nuclear power plants.