阀控式熔体微分3D打印机工作特性的研究

发布时间：2018-04-13 17:29

  本文选题：三维打印 + 熔体微分　； 参考：《中国塑料》2017年07期

【摘要】：提出一种可实现多种塑料颗粒直接打印的阀控式熔体微分三维(3D)打印机,运用多相流及动网格技术对阀腔内非牛顿流体的挤出过程进行数值模拟。结果表明,挤出流量与阀针下移速度、阀针/阀腔直径比均呈正相关关系,且阀针距喷嘴越近、直径比越大,流量波动越大;最佳阀针最大运动距离为0.5~1mm;阀针运动速度/阀腔背压比大于0.5时,熔体出现倒流现象;精确控制各工艺参数可实现稳定按需挤出,提高成型件精度。
[Abstract]:A valve controlled melt differential 3D (3D) printer for direct printing of various plastic particles is proposed. The extrusion process of non-Newtonian fluid in the valve cavity is numerically simulated by means of multiphase flow and dynamic grid technology.The results show that the extrusion flow rate has a positive correlation with the speed of the valve needle moving down and the ratio of valve needle to valve cavity diameter, and the closer the valve needle is to the nozzle, the bigger the diameter ratio is, and the greater the flow fluctuation is.The maximum moving distance of valve needle is 0.5mm, when the ratio of valve needle motion velocity to valve cavity back pressure is greater than 0.5, the melt reverse flow phenomenon appears. The precise control of each process parameter can realize stable extrusion on demand and improve the precision of forming parts.
【作者单位】： 北京化工大学机电工程学院;北京卫星信息工程研究所;
【基金】：国家自然科学基金青年基金资助项目(51403014) 广东省省级科技计划项目(2016B090915001)
【分类号】：TP334.8;TQ320.5
，

本文编号：1745504