期刊
SURFACE & COATINGS TECHNOLOGY
卷 232, 期 -, 页码 290-297出版社
ELSEVIER SCIENCE SA
DOI: 10.1016/j.surfcoat.2013.05.017
关键词
Cold spraying; Computational fluid dynamics (CFD); Numerical simulation; Impact velocity; Total pressure; Divergent length
资金
- EU [FP7-IPACT-268696]
This study investigates the effect of total pressure (P-o) and nozzle divergent length (L-a) on the flow character and particle impact velocity in cold spraying. Computational fluid dynamic (CFD) approach is employed in the present work to achieve this objective. The simulated results indicate that P-o and L-d significantly influence the flow regime and particle acceleration. With gradually increasing P-o, the nozzle exit Mach number (M-e) firstly increases and then fluctuates after P-o exceeds a critical value, finally M-e reaches the maximum value and maintains stable. Differing from M-e, the particle impact velocity (V-p) continually goes up with P-o due to the increasing gas density which can improve the drag force, but the growth rate levels out gradually. Besides, it is also found that Me shows a downward trend with increasing L-d. However, as for V-p, there exists an optimal L-d which can guarantee the particle achieving the maximum V-p. Moreover, for nozzles with larger expansion ratio, the optimal L-d is longer. This optimal length is considered as a consequence of the competition between the particle acceleration time and drag force on the particle surface. (C) 2013 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据