增强高压毛细管类风湿仪粘度数据计算与不确定性的传播,以后交叉威廉姆斯,兰德尔和渡轮 (WLF) 参数适配
Martin Hubmann1, Stephan Schuschnigg1, Ivica Ðuretek1
1Polymer Processing, Department of Polymer Engineering and Science, Montanuniversitaet Leoben, 8700 Leoben, Austria.
Polymers
|July 29, 2023
概括
本研究使用不确定性传播量化了聚合物融粘度测量的不确定性. 纳入这些不确定性可以提高粘度模型的准确性和精度,特别是在较低的剪切率下.
科学领域:
- 聚合物科学 聚合物科学
- 类风病学 类风病学 类风病学
- 测量科学 测量科学 测量科学
背景情况:
- 高压毛细血管类风湿测量是测量聚合物融切割粘度的标准.
- 粘度计算涉及Bagley和Weissenberg-Rabinowitsch校正,容易导致测量不准确.
- 现有的方法缺乏对衍生粘度值的不确定性进行可靠的量化.
研究的目的:
- 提出并展示一种方法来量化聚合物化的剪切粘度测量中的不确定性.
- 评估将粘度不确定性纳入粘度模型参数估计中的影响.
- 为了比较加权与标准余积二次缩小的性能.
主要方法:
- 不确定性传播计算应用于毛细血管类类风湿学数据.
- 使用聚碳酸溶液进行实验验证.
- 使用加权和标准余平方和对交叉WLF粘度模型进行参数估计.
- 用于验证的风力计测量的数值模拟.
主要成果:
- 对于聚碳酸溶液,量化粘度不确定性已经成功得出.
- 配方的加权余和,结合不确定性,在较低的剪速下,模型准确度提高了16%.
- 导出的粘度不确定性导致了更精确的跨WLF模型系数.
- 两种装配方法都显示了高剪速的偏差,可能是由于非异热条件.
结论:
- 量化测量不确定性对于准确地确定聚合物融中的粘度至关重要.
- 将粘度不确定性纳入模型拟合中可以提高参数精度和预测能力.
- 需要进一步的研究来解决高切割速率的偏差,可能涉及非同热流模型.
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