## 毫秒激光打孔过程的数值模拟

Title    The numerical simulation of millisecond laser  drilling process
Abstract
Production field of laser drilling is now widely used technology.The punch speed, high efficiency,simple operation.Laser drilling in this paper is mainly used in aerospace plane on the turbine blades,metal aluminum as the research object,based on the theory of heat transfer and fluid mechanics,millisecond laser perforation physical model is established.Finite element numerical method to simulate millisecond laser drilling of aluminum metal temperature and flow field,thermal gap enthalpy method was used to simulate the aluminum solid liquid phase change process,it is concluded that different energy irradiation and light spot radius, the distribution of transient temperature field and the figure and the relationship between the flow velocity changes over time.Change the laser energy is calculated, the laser parameters on the influence of pore morphology,summed up the optimum parameters of the laser drilling,provide a reference for the optimization of actual drilling.

Keywords  Laser drilling  The finite element method  Laser power

1  绪论    1
1.1  课题研究背景    1
1.2  课题研究目的及意义    1
1.3  激光打孔    2
1.3.1  激光    2
1.3.2  激光打孔原理    2
1.3.3 激光打孔特点    3
1.4  激光打孔技术发展状况    4
1.4.1  激光打孔技术发展现状    4
1.4.2  激光打孔技术发展趋势    4
1.5  本论文研究的主要内容    5
2  模拟方法    6
2.1  有限元法介绍    6
2.2  COMSOL软件介绍    6
2.3  COMSOL建模过程    7
3  数值模拟结果及分析    9
3.1  温度场模拟结果    9
3.2  速度场模拟结果    15
3.3  熔融物迁移    17
3.4  数值模拟与实验对比    18

1  绪论
激光加工技术是现如今一项应用普遍、发展迅速的科学技术，对社会生产生活的进步起着非常重要的作用。利用激光加工技术，可以提高生产效率和产品质量，以及在产业自动化、减少材料的浪费等方面起着重要作用，将成为全球工业中重中之重的产业[1]。激光打孔技术是本课题研究的核心，在航天领域飞机涡轮叶片上有重要应用[2]。 源`自*六)维[论*文'网www.lwfree.cn

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