| Effect of cold spray particle conditions and optimal standoff distance on impact velocity |
| |
| 作者姓名： | 王晓放 殷硕 徐宝鹏 |
| |
| 作者单位： | 1. 大连理工大学能源与动力学院,辽宁大连,116024
2. 金斯顿大学工程学院,英国伦敦SW153DW |
| |
| 基金项目： | “973”National Basic Research Program of China(Grant No.2009CB724303); National Natural Science Foundation of China(Grant No.50476075); Chinese Ministry of Education′s Academic Award for Outstanding Doctoral Student~~ |
| |
| 摘 要： | 冷喷涂中,粒子撞击基板时的速度对涂层形成起到至关重要的作用,而适当的喷涂距离可以使喷涂粒子获得较高的速度.利用商用CFD软件Fluent模拟了喷嘴外超音速流场的分布情况,分析了粒子自身条件对冲击速度的影响,同时提出了确定粒子与基板最佳距离的方法.分析发现,小尺寸、低密度以及不规则形状的粒子容易受到喷嘴外产生的膨胀波、斜激波和基板前的弓形激波影响.随着能量的耗散或当粒子穿过弓形激波时,这些粒子的速度明显下降.另外,在基板与喷嘴之间存在一个最佳距离,它的确定需要两个必要条件：一是基板处的气流必须保持较低的速度,从而使弓形激波的强度相对较弱;二是粒子须经膨胀波加速2次,即弓形激波前具有2个膨胀波,以确保气体可充分利用膨胀波的加速.
|
| 关 键 词： | 冷喷涂 数值模拟 弓形激波 基板最佳距离 |
Effect of cold spray particle conditions and optimal standoff distance on impact velocity |
| |
| QWANG Xiao-fang,YIN Shuo,XU Bao-peng.Effect of cold spray particle conditions and optimal standoff distance on impact velocity[J].Journal of Dalian University of Technology,2011,51(4):498-504. |
| |
| Authors: | QWANG Xiao-fang YIN Shuo XU Bao-peng |
| |
| Institution: | WANG Xiao-fang1,YIN Shuo1,XU Bao-peng2(1.School of Energy and Power Engineering,Dalian University of Technology,Dalian 116024,China,2.Faculty of Engineering,Kingston University,London SW15 3DW,England) |
| |
| Abstract: | The impact velocity of particles plays an important role in coating formation of cold spray.A proper standoff distance from the nozzle exit to the substrate surface can ensure sprayed particles to achieve relatively high impact velocities.Numerical simulations were conducted by using a CFD software,Fluent,to predict the supersonic flow field outside the nozzle.Based on the simulation results,the effect of particle conditions on impact velocity is studied and also the way to determine the optimal standoff di... |
| |
| Keywords: | cold spray numerical simulation bow shock waves optimal standoff distance |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《大连理工大学学报》浏览原始摘要信息 |
| 点击此处可从《大连理工大学学报》下载免费的PDF全文 |
|
