不同类型的挤出膨胀从裂口模具:一个速度中心假设和数值验证
Guangdong Zhang1, Xinyu Hao1, Linzhen Zhou1
1School of Mechanical Engineering, Yancheng Institute of Technology, Yancheng 224051, China.
Polymers
|March 14, 2026
概括
这项研究提出了一个新的理论框架,用于绘制聚合物挤出物膨胀的几何和动力学方面,将它们与粘性弹性效应分开. 该模型与对高面积比率模具的模拟有很好的一致性.
科学领域:
- 聚合物加工加工的方法
- 类风病学 类风病学 类风病学
- 计算流体动力学 计算流体动力学
背景情况:
- 聚合物加工中的异型挤出物膨胀主要是由于粘弹性回收.
- 现有的模型往往没有明确分离几何和动力学贡献.
研究的目的:
- 开发一个理论框架来隔离和绘制挤出膨胀的几何和动力组件.
- 为多速度中心假设提供数学概念证明.
- 为了将直径膨胀比延长到矩形切口模具的局部流量场.
主要方法:
- 提出了一种多速度中心假设,使用一次性材料流校准参数.
- 使用异热,不弹性的功率定律流体CFD模拟用于动力学一致性测试.
- 从粘弹性应力放松进行分离的几何映射.
主要成果:
- 分析预测显示,在高面积比率模具的核心区域,CFD数据与CFD数据有很好的一致性 (误差<5%).
- 由于无限裂假设和速度衰减,在模具边缘附近观察到偏差.
- 该框架为动态映射提供了一个基本的数学基础.
结论:
- 半经验动力学绘图成功地将外挤膨胀中的几何和动力学因素分离出来.
- 需要进一步的经验纠正3D流动动力学近死亡边缘.
- 这种方法可以为未来的反向压形状设计和形状扭曲补偿提供信息.
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