喷嘴出口直径对冷喷涂射流流场及基板最佳位置影响的数值分析  

Numerical Investigations on the Effect of Nozzle Outlet Diameter on Jet Flow Field and Optimal Standoff Distance in Cold Spraying

作　　者：殷硕[1] 王晓放[1] 李文亚[2] 

机构地区：[1]大连理工大学能源与动力学院,大连116024 [2]西北工业大学材料学院摩擦焊接陕西省重点实验室,西安710072

出　　处：《中国表面工程》2013年第1期74-78,共5页China Surface Engineering

基　　金：国家自然科学基金(50476075)

摘　　要：冷喷涂过程中,喷嘴出口后射流流场的波系结构对粒子冲击基板时的速度有很大影响。利用CFD软件Fluent对不同出口直径的喷嘴后单相自由射流和两相冲击射流流场进行了模拟计算。结果表明,喷嘴出口直径对冷喷涂射流流场及粒子冲击速度会产生一定的影响;在喷嘴出口与基板之间存在一个最佳距离使得粒子能够获得较大的冲击速度,该最佳距离会随喷嘴出口直径的增加而线性增加。The structure of the flow field outside the nozzle a significantly affects the particles＇ impinging ve- locity in cold spraying. In this study, the numerical method is used to investigate the single-phase free jet flow and the two-phase impinging jet flow outside the nozzle by using a CFD software fluent. The results show that the diameter of the nozzle outlet has an important effect on the gas flow field and particle impinging veloc- ity. Moreover, there exists an optimal standoff distance between the nozzle outlet and the substrate, which can ensure the sprayed particle to attain the maximum impinging velocity. The optimal standoff distance line- arly increases with increasing nozzle outlet diameter.

关 键 词：冷喷涂 自由射流 冲击射流 数值模拟 最佳距离 

分 类 号：TG174.442[金属学及工艺—金属表面处理] O241[金属学及工艺—金属学]