Ansys Fluent UDF（2）：UDF概述

小瓶灌装是制药、化工和食品等许多行业的重要过程，其物理性质与瓶子灌装相似，瞬态多相模拟过程是灌装和精加工过程中不可或缺的一部分。 一、研究目的：研究用充水管在小瓶几何形状中充水了解填充模式；评估液体溢出或飞溅（如有）。二、边界条件从入口（蓝色实线箭头所示）供水2秒，2秒填充过程中的进水速度为3 ml/sec；小瓶中收集的预期水量：如果没有溢出或飞溅，在填充过程结束时为6ml；总模拟时间为5秒，以使水界面在填充循环后沉降；在注水过程中，小瓶中的空气从压力出口边界（由红色实线箭头表示）逸出。三、Geometry and Mesh （1）小瓶几何形状将实际三维几何体建模为二维轴对称模型，以进行快速模拟。（2）小瓶尺寸小瓶灌装容量: 21ml；高度(H): 55mm；小瓶最大直径 (OD): 30mm；瓶颈直径 (ID): 12.6mm；填充管直径 (D): 4mm。（3）网格细节0.3mm大小的均匀四边形网格总网格数：6.5k个单元；在Ansys Fluent中，最终只对流体体积进行网格划分和导入。四、Case setup（1）Materialopen the materials database→Select water-liquid→click Copy and close the panel；默认有air的材料。（2）Physical modelopen the Multiphase Model→Volume of Fluid- Select “Implicit” formulation;- Keep the default “Sharp” for Interface Modelling;- Keep the default “Number of Eulerian Phases” as 2;- Click Apply.Go to Phases Tab- For Primary Phase, select Phase Material as air, Name as air and click Apply;- For Secondary Phase, select Phase material as water- liquid, Name as water and click Apply.Go to Phase Interaction Tab- Surface tension effects are not considered in this problem. In a high fidelity, 3D simulation, surface tension physics could be included. （3）Boundary conditions - Inlet &. outletSelect Phase as “mixture”. Click “Edit” to open the Velocity Inlet panel for mixture，输入0.239 m/s的速度幅值，这是与3 ml/sec的体积流量相对应的进水速度；In the Turbulence Specification Method select “ Intensity and Hydraulic Diameter”. Input Turbulent Intensity as 2% and Hydraulic Diameter as 4mm. （4）Run CalculationSet Total Time (s) as “5”;Set Global Courant Number as “5”;Set Number of Fixed Time Steps as “20”;Set Initial Time Step Size (s) as “0.001”;Click Settings to open “Adaptive Time Stepping” panel：- Set Minimum Time Step Size (s) of “0.0001”;- Set Maximum Time Step Size (s) of “0.05” . Click “Save”. 五、Results: Contours of volume fraction of water over time 为了实现高灌装线生产率和卓越的产品质量，确定给定液体类型的最佳灌装速率非常重要。Ansys Fluent能高效解决此类问题且精度在行业内认可度较高。来源：艾羽科技