设计,建模和验证用于可持续聚合物加工的紧型,节能混合螺丝
David O Kazmer1, Stiven Kodra2
1Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, MA 01854, USA.
Polymers
|January 25, 2025
概括
本研究引入了一种用于节能挤压的新型混合螺丝,实现更高的吞吐量和更好的热均性. 创新的设计为可持续的聚合物加工应用提供了更好的性能.
科学领域:
- 聚合物加工工程 聚合物加工工程
- 材料科学与工程 材料科学与工程
- 机械工程 机械工程 机械工程
背景情况:
- 单螺丝挤出是一种广泛使用的聚合物加工技术.
- 能源效率和材料均性对于可持续的聚合物加工至关重要.
- 传统的螺丝通常具有很长的长度对直径比,限制了它们在紧系统中的应用.
研究的目的:
- 设计,建模和验证一种用于节能单螺丝挤压的新型混合螺丝.
- 为了增强塑化和热均性,使用具有特殊特性的短长直径 (L / D) 比率螺丝.
- 评估用于加工高冲击聚钢 (HIPS) 和回收聚烯 (rPP) 的混合螺丝的性能.
主要方法:
- 一个混合螺丝的设计,其L/D比为8:1,双飞行,可变距离和反旋转的混合槽.
- 非同热,非牛顿模拟以建模热和流动行为.
- 实验验证使用20毫米试验尺度挤出机在不同的螺丝转速和桶温度下进行实验验证.
主要成果:
- 证明了质量输出对螺丝转速的强有力的线性依赖,最大吞吐量为0.58公斤/小时 (HIPS) 和0.74公斤/小时 (rPP) 在40 RPM.
- 实现了0.264 kWh/kg (HIPS) 和0.344 kWh/kg (rPP) 的特定能耗 (SEC),效率分别为31.5%和56.5%.
- 与传统螺丝相比,展示了提高能源效率和减少停留时间的分布.
结论:
- 新的混合螺丝设计是有效的节能单螺丝挤出.
- 螺丝的特性增强了塑化和热均性,适合加工HIPS和rPP.
- 潜在的应用包括紧挤压系统,3D打印和可持续的聚合物/生物塑料加工.
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