高温高压蒸汽管道颗粒运动及分离特性研究  

Motion and Separation Characteristics of Oxide Scale Particles in High Temperature and High Pressure Steam Pipe

作　　者：阮班铖 蔡柳溪 李云[1] 王顺森[2] 颜晓江 毛靖儒[2] RUAN Bancheng;CAI Liuxi;LI Yun;WANG Shunsen;YAN Xiaojiang;MAO Jingru(School of Chemical Engineering and Technology,Xi’an Jiaotong University,Xi’an 710049,China;Institute of Turbomachinery,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学化学工程与技术学院,西安710049 [2]西安交通大学叶轮机械研究所,西安710049

出　　处：《西安交通大学学报》2022年第2期47-56,共10页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(52076173);中国博士后科学基金资助项目(2020M680157);中央高校基本科研业务费资助项目(sxxj 032020009)。

摘　　要：为了彻底解决锅炉管系脱落的氧化皮颗粒对汽轮机叶片冲蚀损伤、阀门卡涩、抽汽及疏水系统堵塞等问题,以某超超临界汽轮发电机组主蒸汽管路为原型,对蒸汽管道内的汽固两相流动进行了系统的数值模拟分析,探索了颗粒尺寸、蒸汽参数、弯管曲率半径对氧化皮颗粒运动行为的影响。在此基础上,利用蒸汽管道原有弯管结构设计了弯管颗粒分离器,并对其分离特性、压损特性和热力系统经济性进行了系统的计算分析。结果表明:氧化皮颗粒进入蒸汽管道弯管后,在离心力作用下,所有尺寸颗粒均会向管道压力面逐渐贴近集中,颗粒尺寸越大,弯管的曲率半径越大,蒸汽参数越低,氧化皮颗粒在弯管出口截面上就越集中;在最佳抽汽占比M为0.50%工况下,弯管颗粒分离器对100μm以上氧化皮颗粒的分离效率达到90%以上,分离装置对主蒸汽产生的压力损失约为21 kPa;提出将分离后的汽固两相混合物净化后输送到最高参数的高压加热器进行回收利用的方案,不同抽汽比工况下颗粒分离和蒸汽回收工艺对机组热耗和功率的影响均小于0.2%。该研究结果对于延长火电机组关键设备高效服役寿命具有重要意义。To completely solve the problems,such as the erosion damage of steam turbine blades,the valve jam,and the blockage of the extraction and drainage system caused by the oxide particles falling off the boiler piping system,a systematically numerical simulation analysis of the steam-particle two-phase flow in the steam pipe is carried out based on the prototype of main steam pipe of an ultra-supercritical steam turbine generator unit.The effects of particle size,steam parameters and elbow curvature radius on the motion behavior of oxide scale particles are explored.Then an elbow particle separator is designed by using the original elbow structure in main stream pipe,and the separation characteristics,pressure loss and thermal system economy are calculated and analyzed.The results show that after the oxide scale particles enter the steam pipe elbow,particles of all sizes gradually tend to concentrate on the pipeline pressure surface under the action of centrifugal force.The larger the particle size,the greater the curvature radius of the elbow,the lower the steam parameter,the more concentrated the oxide scale particles get on the elbow outlet cross-section.When the optimal steam extraction ratio M equals to 0.50%,separation efficiency of the oxide scale particles above 100μm is more than 90%by utilizing the elbow particle separator,and the pressure loss of the separation device to the main steam is about 21 kPa.A scheme of purifying the separated steam-particle two-phase mixture and transporting it to the highest parameter high-pressure heater for recycling is proposed.The effect of particle separation and steam recovery processes on the heat consumption and power of the unit in different steam extraction ratios is less than 0.2%.

关 键 词：主蒸汽管道 弯管分离器 汽固两相流 数值模拟 热力系统 

分 类 号：TK284[动力工程及工程热物理—动力机械及工程]