紧耦合气雾化拉瓦尔喷盘结构优化  

Structural Optimization of Laval Nozzle Used for Close-Coupled Gas Atomization

作　　者：徐啸林 卢林[1] 吴文恒[1] XU Xiaolin;LU Lin;WU Wenheng(Research and Application Center for additive manufacturing materials,Shanghai Research Institute of Materials Co.,Ltd.,Shanghai 200437,China;School of Resources and Environmental Engineering,Shanghai Polytechnic University,Shanghai 201209,China)

机构地区：[1]上海材料研究所有限公司,上海市工程材料应用与评价重点实验室,上海200437 [2]上海第二工业大学资源与环境工程学院,上海201209

出　　处：《机械工程材料》2024年第4期103-110,共8页Materials For Mechanical Engineering

基　　金：上海市启明星培育(扬帆专项)项目(23YF1411400);上海市青年科技启明星计划项目(20QB1401100);上海材料研究所技术创新项目(23SG-04)。

摘　　要：采用计算流体动力学法模拟了紧耦合气雾化拉瓦尔喷盘气流喷射角(40°,50°,60°,70°,80°)、气流喷射宽度(15,20,25,30,35 mm)、导流管伸出长度(0.5,4.5,8.5 mm)对雾化室流场气流速度分布及其y轴上气流交汇点气流速度和导液管出口处静压的影响,得到了喷盘优化结构参数;采用优化结构喷盘制备18Ni300模具钢紧耦合气雾化粉末,测定了其性能。结果表明:随着气流喷射角增加,流场最大气流速度减小,气流交汇处气流速度和导液管出口处静压均增大;随着导流管伸出长度增加,流场最大气流速度先减小后增加,导液管出口处静压减小,气流交汇点气流速度未发生显著变化;随着气流喷射宽度增加,流场最大气流速度未产生显著变化,气流交汇点气流速度和导液管出口处静压均减小;根据模拟结果得到喷盘优化结构参数为气流喷射角60°、气流喷射宽度30 mm、导流管伸出长度4.5 mm,此条件下制得的18Ni300模具钢紧耦合气雾化粉末形状规则,尺寸小且均匀,细粉收得率最大,粉末流速和松装密度较大,综合性能最佳。The effects of jet angle(40°,50°,60°,70°,80°),jet width(15,20,25,30,35 mm),and diversion pipe extension length(0.5,4.5,4.5,8.5 mm)of Laval nozzle used for close-coupled gas atomization on flow velocity of flow field,flow velocity at the flow junction and the static pressure at the outlet of liquid pipe along y-axis in atomizing chamber were simulated by computational fluid dynamics(CFD).The optimized structure parameters of the nozzle were obtained.The 18Ni300 die steel close-coupled gas atomizated powders were prepared with the optimal-structured nozzle,and the performane of the powder was measured.The results show that with the increase of jet angle,the maximum flow velocity of the flow field decreased,and the flow velocity at the flow junction and the static pressure at the outlet of liquid pipe increased.With the increase of the diversion pipe extension length,the maximum flow velocity of the flow field decreased first and then increased,the static pressure at the outlet of liquid pipe decreased,and the flow velocity at the flow junction did not change significantly.With the increase of jet width,the maximum flow velocity of the flow field did not change significantly,and the flow velocity at the flow junction and static pressure at the outlet of liquid pipe decreased.According to the simulation results,the optimized structure parameters of nozzle were listed as follows:jet angle of 60°,jet width of 30 mm and diversion pipe extension length of 4.5 mm.In this case,the 18Ni300 die steel close-coupled gas atomizated powder had regular shapes and small and uniform size,the fine powder yield was the largest,and the powder flow rate and apparent density were relatively large.The comprehensive performance of the powder was the best.

关 键 词：紧耦合气雾化 拉瓦尔喷盘 喷盘结构 金属粉末 

分 类 号：TF123[冶金工程—粉末冶金]