不锈钢/陶瓷复合结构激光切割流场仿真模拟  

Simulation Study of Flow Field on Laser Cutting of UO_(2)/Stainless Steel Composite Structure

作　　者：宋妮妮 林英华[1] 朱卫华[2,3] 陈志勇[2,3] 王新林 Song Nini;Lin Yinghua;Zhu Weihua;Chen Zhiyong;Wang Xinlin(School of Mechanical Engineering,University of South China,Hengyang,Hunan 421001,China;College of Electrical Engineering,Uni-versity of South China,Hengyang,Hunan 421001,China;Ultra-fast Wiener Technology and Laser Advanced Manufacturing Hunan Provin-cial Key Laboratory,University of South China,Hengyang,Hunan 421001,China)

机构地区：[1]南华大学机械工程学院,湖南衡阳421001 [2]南华大学电气工程学院,湖南衡阳421001 [3]南华大学超快微纳技术与激光先进制造湖南省重点实验室,湖南衡阳421001

出　　处：《机电工程技术》2022年第3期108-111,共4页Mechanical & Electrical Engineering Technology

摘　　要：为探究UO_(2)陶瓷芯块复合316Ti不锈钢包壳管激光切割过程辅助气体流场的分布特点,通过ANSYS软件建立了辅助气体流场的仿真模型。使用UDF功能,构建了深度随气/液变化的自适应热源模型,分析了激光切割过程中温度分布特点。在设定边界条件(压力入口、压力出口、自由表面、壁面、对称面)和材料热物性参数(比热容、热导率)后,利用k-ε湍流模型分析了辅助气体从喷嘴流出后速度、压力的变化。结果表明在对称面上激光切割温度呈圆锥形分布,热影响区范围小,激光热源集中;辅助气体流动速度过小,熔融的金属材料无法被去除,工件将无法完全被切透;辅助气体在喷嘴内外存在较大的压力差,在靠近切削表面时压力增高,但压力梯度减小,入口压力对辅助气体流场的影响是决定性的。通过流场仿真结果可以优化辅助气体流出速度、入口压力等参数,保证在激光切割过程中辅助气体的除渣能力,进而保证切割质量。In order to explore the distribution characteristics of auxiliary gas flow field in laser cutting process of UO_(2) ceramic pellet composite 316Ti stainless steel cladding,a simulation model of auxiliary gas flow field was established by ANSYS software.Using UDF function,an adaptive heat source model with depth varying with gas/liquid was constructed,and the characteristics of temperature distribution in laser cutting process were analyzed.After setting the boundary conditions(pressure inlet,pressure outlet,free surface,wall surface,symmetry plane)and material thermal properties(specific heat capacity,thermal conductivity),the k-εturbulence model was used to analyze the velocity and pressure of the auxiliary gas after flowing out of the nozzle.The results show that the laser cutting temperature on the symmetrical plane is conical,the heat affected zone is small,and the laser heat source is concentrated.If the auxiliary gas flow speed is too small,the molten metal material cannot be removed and the workpiece cannot be completely cut through.The auxiliary gas has a large pressure difference inside and outside the nozzle.When the auxiliary gas approaches the cutting surface,the pressure increases,but the pressure gradient decreases.The influence of inlet pressure on the auxiliary gas flow field is decisive.Through the flow field simulation results,the parameters such as the outflow velocity and inlet pressure of the auxiliary gas can be optimized to ensure the slag removal ability of the auxiliary gas in the laser cutting process,so as to ensure the cutting quality.

关 键 词：流场 不锈钢/陶瓷复合结构 激光切割 

分 类 号：TG485[金属学及工艺—焊接]