针对近年来炼厂中出现的烟气轮机叶片上结垢严重的问题,采用欧拉-拉格朗日的数值模拟方法对烟机内的气固二相流动,特别是对固体颗粒相的运动规律进行了探索研究.结果表明,不同粒径的催化剂颗粒在叶片表面的运动轨迹是不同的,所造成的后果也不相同,粒径较小(＜3 μm)的颗粒易在叶片压力面上发生沉积和结垢,粒径较大(20μm)的颗粒易引起叶片的冲蚀与磨损；且由数值模拟所预测的烟机磨损与结垢发生的位置与生产实际中的情况是相一致的,可为进一步揭示烟机动叶片上的结垢原因和优化炼厂中烟机本身的操作条件提供理论基础与实践指导.%Aiming at the problem of fouling occurred in the FCC flue gas turbines in many refineries, the gas-solid two-phase flow in flue gas turbines was studied by using Euler-Lagrange numerical simulation method, especially the behavior of fine powders in exhaust gas on the surface of rotors was explored by employing Discrete Phase Model (DPM). The results demonstrate that the trajectories of particles with various diameters are remarkably different, giving rise to various consequences; small particles with a diameter less than 3 μm always accumulate and melt to form fouling on the pressure-side surface of rotors, while large particles with a diameter more than 20 μm often induce erosion at the trailing edge of rotors. Besides, the predicted locations of erosion and deposition are well consistent to the real case in refinery. These results can provide the theoretical foundation for revealing the catalyst scaling mechanism and optimization of operating conditions of FCC flue gas turbines.
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