摘要
目的为了解决雾化法磁性磨料制备过程中,雾化喷嘴容易发生冲蚀磨损而无法形成有效流场的问题,分析雾化喷嘴的冲蚀磨损机理,为雾化喷嘴的设计提供理论依据。方法选用Al2O3硬质磨料颗粒、Si C材料的喷嘴,运用理论分析与计算机模拟(CFD)相结合的方法,探究雾化喷涂冲蚀磨损的机理,并研究雾化压力与最大冲蚀磨损率的关系。结果运用理论分析,得出了雾化喷嘴的冲蚀磨损形式为脆性断裂与微切削两种。运用CFD计算机模拟分析,得出了雾化喷嘴的冲蚀磨损分布图,其冲蚀磨损率随着雾化压力的增加而增加。当雾化压力为3 MPa时,雾化喷嘴的最大冲蚀磨损率达到了5.3×10-7 kg/(m2·s);当雾化压力为5 MPa时,雾化喷嘴的最大冲蚀磨损率达到了1.3×10-6 kg/(m2·s),较3 MPa时增加了59%。结论可以采取将硬质磨料注入与雾化工序分离的方法来改进雾化喷嘴的结构,从而减少在制备磁性磨料过程中硬质磨料颗粒对雾化喷嘴内壁的冲蚀磨损。
Since atomizing nozzle is easily subject to erosive wear during preparation of magnetic abrasive in atomization method, the work aims to solve the difficulty in forming effective flow field, analyze erosive wear mechanism of atomizing noz- zle, and provide theoretical basis for design of atomizing nozzle. A1203 hard abrasive particles and SiC nozzle were selected, theoretical analysis and computer simulation （CFD） were combined to explore erosive wear mechanism, and atomization pres- sure was selected to simulate its relationship with maximum erosive wear rate, Based upon theoretical analysis, it was concluded that the erosive wear forms of the atomizing nozzle were brittle fracture and micro-cutting. Based upon CFD computer simula- tion analysis, both erosive wear distribution diagram of the atomizing nozzle, and the rule that erosive wear rate increased with the increase of atomization pressure were obtained. At the atomization pressure of 3 MPa, the maximum erosion wear rate of atomizing nozzle reached 5.3×10^-7 kg/（m^2 · s）. At the atomization pressure of 5 MPa, the maximum erosion wear rate reached 1.3×10^-6 kg/（m2 s）, 59% higher than that at 3 MPa. A method of separating the hard abrasive injection and atomization process is proposed to improve structure of the atomizing nozzle, so as to reduce erosive wear of the hard abrasive particles on inner wall of the atomizing nozzle during preparation of the magnetic abrasive.
出处
《表面技术》
EI
CAS
CSCD
北大核心
2017年第9期121-126,共6页
Surface Technology
基金
国家自然科学基金面上项目(51375285)~~
关键词
雾化法
气-固两相流
雾化喷嘴
冲蚀磨损
数值模拟
磁性磨料
atomization method
gas-solid two phase flow
atomizing nozzle
erosive wear
numerical simulation
magneticabrasive
