| 引用本文: | 武云文,刘思思,谢玉莹,姜胜强,杨世平,刘金刚.超音速火焰喷涂过程中粒子运动特性的数值模拟[J].材料科学与工艺,2021,29(5):1-8.DOI:10.11951/j.issn.1005-0299.20210080. |
| WU Yunwen,LIU Sisi,XIE Yuying,JIANG Shengqiang,YANG Shiping,LIU Jingang.Numerical simulation for dynamic characteristics of particles during high-velocity oxygen-fuel spraying[J].Materials Science and Technology,2021,29(5):1-8.DOI:10.11951/j.issn.1005-0299.20210080. |
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| 摘要: |
| 热喷涂涂层质量很大程度上是由颗粒沉积时的状态决定,颗粒不仅受到粒径尺寸的影响,还与飞行过程中焰流特性密切相关。本文以JP8000型超音速火焰喷涂系统(HVOF)喷涂过程为研究对象,采用计算流体动力学方法探究不同氧油质量比下焰流行为和计算域内的燃烧特性；分析不同粒径的颗粒在焰流场内的轨迹特性和速度、温度演变规律,依据数值模拟结果优化工艺参数。计算结果表明:氧油比为3时,HVOF系统内焰流温度最高、速度最快,表明氧油充分燃烧；颗粒注入后可能与枪管壁发生碰撞,且其粒径越大,碰撞发生的临界入射速度越小,碰撞后的粒子会二次穿越焰流中心；颗粒粒径越大,受焰流作用时加热、加速越缓慢,在喷枪内到达的最高温度和最大速度越小。 |
| 关键词: 超音速火焰喷涂 计算流体动力学 氧油比 焰流行为 颗粒行为 |
| DOI：10.11951/j.issn.1005-0299.20210080 |
| 分类号:TG174.44 |
| 文献标识码:A |
| 基金项目:国家自然科学基金资助项目(52075465)；湖南省自然科学基金资助项目(2018JJ4055)；复杂轨迹加工工艺及装备教育部工程研究中心开放课题(FZGJ2020-005). |
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| Numerical simulation for dynamic characteristics of particles during high-velocity oxygen-fuel spraying |
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WU Yunwen, LIU Sisi, XIE Yuying, JIANG Shengqiang, YANG Shiping, LIU Jingang
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(School of Mechanical Engineering, Xiangtan University, Xiangtan 411105, China)
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| Abstract: |
| The quality of thermal spray coating is largely determined by the state of the particles when they are deposited. The particles are not only affected by the particle size, but also closely related to the characteristics of the flame during flight. The spraying process of JP8000 high-velocity oxygen-fuel spraying (HVOF) system was investigated. By using the computational fluid dynamics method, the flame behavior and the combustion characteristics were studied in the computational domain under different oxygen-fuelratios(O/F).The trajectory characteristics and velocity and temperature evolution laws of particles of different sizes were analyzed in the flame flow field, and the process parameters were optimized based on the numerical simulation results. Calculation results show that when the oxygen-fuel ratio was 3, the flame flow temperature in the HVOF system was the highest and the speed was the fastest, indicating that the oxygen-fuel is fully burned.After the particles were injected, they might collide with the barrel wall, and the larger the particle size was, the smaller the critical incident velocity was for collision.The particles after the collision would pass through the center of the flame for a second time.The larger the particle size was, the slower the heating and acceleration were when being acted on by the flame flow, and the lower the maximum temperature and maximum speed were in the spray gun. |
| Key words: high-velocity oxygen-fuel spraying (HVOF) computational fluid dynamics oxygen-fuel ratios flame behavior particle behavior |
