摘要
为了评估冷凝器系统的阴极保护效果,建立了冷凝器系统样机,通过试验评估了阴极保护系统的保护效果,然后开展了基于边界元法的冷凝器保护电位仿真与优化,优化计算结果与实测结果相一致,从而利用仿真计算预测了多根换热管系统的保护效果,为实际工况提供指导。样机实测结果显示:端盖和管板的保护电位维持在-600~-610 mV左右,得到完全保护;换热管距离管板处30 cm范围内,其电位小于-450 mV,得到完全保护,距离越远保护效果越弱;实测结果与仿真计算结果偏差最大值不超过15%,表明二者具有较好的一致性,仿真可对实际工况具有指导意义。仿真预测表明,27根管模型的端盖和管板得到完全保护,换热管电位低于-450 mV的长度为16.8 cm;63根管模型的端盖和管板也得到完全保护,换热管电位低于-450 mV的长度为13.0 cm。综上所述,目前的阴极保护方案可有效保护冷凝器端盖、管板和部分靠近管板的换热管;在牺牲阳极的数量固定的前提下,换热管数量的增加会导致其保护距离逐渐减少。
Aiming at evaluating the cathodic protection effect of the condenser system,a prototype of the condenser system was established,and the protection effect of the cathodic protection system was evaluated through experiments.Subsequently,the simulation and optimization of the condenser protection potential based on the boundary element method were carried out,and the optimized calculation results were consistent with the measured results.Therefore,the simulation results were used to predict the protection effect of multiple heat exchange tube systems,which could provide the guidance for actual working conditions.The actual measurement results of the prototype showed that the protection potentials of the end cap and the tube sheet were maintained at about-600 to-610 mV,indicating the full protection was obtained;The potential of the heat exchange tube was less than-450 mV within 30 cm of the tube sheet,which obtained the full protection,and the longer the distance the weaker the protection effect;The maximum deviation between the actual measurement result and the simulation calculation result did not exceed 15%,suggesting they had good consistency and the simulation could guide the actual working conditions.Furthermore,the simulation prediction showed that the end caps and the tube sheet of the 27 tubes model was fully protected,the length of the heat exchange tube potential lower than-450 mV was 16.8 cm;The end caps and tube sheets of the 63 tubes model were also fully protected,and the length of the heat exchange tube potential lower than-450 mV was 13 cm.In summary,the current cathodic protection scheme could effectively protect the condenser end cover,tube sheet and the heat exchange tube near the tube sheet.Under the premise of a fixed number of sacrificial anodes,the number increase of heat exchange tubes would lead to the gradual decrease of its protection distance.
作者
张宇
刘亚鹏
李相波
李开伟
张繁
仝宏韬
ZHANG Yu;LIU Ya-peng;LI Xiang-bo;LI Kai-wei;ZHANG Fan;TONG Hong-tao(State Key Laboratory for Marine Corrosion and Protection,China Shipbuilding Industry 725 Research Institute,Qingdao 266101,China)
出处
《材料保护》
CAS
CSCD
2021年第4期27-31,85,共6页
Materials Protection
关键词
冷凝器
阴极保护
数值仿真
condenser
cathodic protection
numerical simulation
