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在均衡分子动力学模拟中使用一致的方法计算剪切粘度:对1 - 十烯寡合体的应用
Luís Fernando Mercier Franco1,2, Abbas Firoozabadi2,3
1Universidade Estadual de Campinas, Av. Albert Einstein, 500, Campinas, 13083-852, Brazil.
The journal of physical chemistry. B
|November 9, 2023
概括
本研究比较了使用分子动态计算剪切粘度的两种方法. 一种方法被发现是一致的,并应用于二氧化碳加厚应用的聚α-olefins.
科学领域:
- 流体动力学 流体动力学
- 材料科学是一种材料科学.
- 计算化学是一种计算化学.
背景情况:
- 精确的剪切粘度计算对于流体流动和工业过程至关重要.
- 聚α-olefins (PAO) 用于诸如二氧化碳加厚等应用,以增强石油回收和封存.
- 在二氧化碳混合之前,了解PAO粘度对于设计上游管道至关重要.
研究的目的:
- 为了比较两个Green-Kubo形式主义方法来计算剪切粘度.
- 识别和纠正剪切粘度计算方法中的不一致性.
- 应用一种经过验证的方法来计算1 - 十烯寡合物的粘度.
主要方法:
- 利用格林-库博形式主义与平衡分子动力学模拟.
- 用两种不同的方法分析了无痕,对称的压力张量计算.
- 使用超临界二氧化碳,n-pentane 和 n-decane 的验证剪切粘度计算.
主要成果:
- 在两种分析方法之间的剪切粘度值中发现了差异.
- 确定一种方法是一致的,并通过缩放对角组件波动来纠正另一种方法.
- 成功计算了各种1-decene寡合体的剪切粘度,包括更大的结构.
结论:
- 这项研究验证了通过分子动力学计算剪切粘度的一致方法.
- 这种经过验证的方法对于准确预测二氧化碳加厚应用中的聚α-烯酸的行为至关重要.
- 这项研究为优化涉及PAO和CO2注入的工业流程提供了必要的数据.
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