加氢空冷器注剂T型管内气-液流动特性的数值模拟

摘要

In order to reveal the erosion thinning formation mechanism with the action of gas-liquid two-phase in the injection T-tube section before the hydrogenation reaction effluent air cooler (REAC) system,the process injection T-tube was taken as the study object,the relevant technical process was analyzed and the discrete model of structure based on its geometric feature was built.Subsequently the Mixture model and Realizable k-ε model were chosen in this computational fluid dynamics (CFD) simulation for researching flow characteristics under operation condition,including water phase fraction,turbulent kinetic energy,wall shear stress and other parameters' distribution.The results indicated that:at the position of maximum value in water phase fraction and shear stress,i.e.between x=-0.15 m and x=-0.26 m,the pipe is prone to blockage and leak,which reasonably agrees with the distribution of pipe remaining wall thickness obtained by using ultrasonic thickness gauges.%以加氢反应流出物空冷器(简称加氢空冷器)系统前的工艺注剂T型管为研究对象,分析其工艺过程,基于工艺注剂T型管的几何特征建立结构离散模型,选择Mixture模型和Realizable k-ε模型对其在操作工况下的流动特性进行计算流体动力学(CFD)模拟,考察不同注剂T型管结构的管内水相分率、湍动能、剪切应力等流体动力学参数的分布规律,揭示气-液两相流动作用下注剂T型管段的冲蚀减薄现象的形成机理.研究结果表明:水相分率及剪切应力最大的位置,即横坐标x位于-0.15～-0.26 m之间,管道易发生穿孔泄漏.超声波测厚仪测试获得的管道剩余壁厚与数值预测的结果基本吻合.