高温液体的粘度通过被动微风学
1Department of Nuclear Engineering, North Carolina State University, Raleigh, North Carolina 27607, USA.
The Review of scientific instruments
|March 3, 2025
概括
一种新型的被动微风学仪器准确地测量了高温至760°C的液体粘度. 这种高温粘度计提供精确的粘度测量,不需要校准液体或材料属性数据.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 发展工具发展工具
背景情况:
- 在高温下精确测量液体粘度对于各种工业和科学应用至关重要.
- 传统的粘度测量方法在高温下经常面临挑战,包括材料限制和复杂的校准程序.
研究的目的:
- 开发和验证一种新型仪器,用于测量液体在高温下动态粘度,使用被动微风学.
- 为了证明仪器在不需要校准液体或对材料性能事先了解的情况下能够确定粘度.
主要方法:
- 使用暗场光学显微镜和定制高温激光传输炉的被动微观学.
- 通过使用斯托克斯-爱因斯坦-萨瑟兰关系,分析了火焰密封毛细血管内的微球的布朗轨迹.
- 在20-450°C的温度范围内,用糖和水混合物,水和化酸盐验证了粘度计.
主要成果:
- 对所有测试液体和温度的测量和文献粘度值达成良好一致.
- 对扩散系数 (<1%) 和粘度 (2%-3.3%) 的不确定性很低,粘度不确定性受到微球尺寸分布的限制.
- 粘度计成功运行至760°C,样本体积小 (<1毫升) 和采集时间快 (≈1分钟).
结论:
- 开发的被动微风学仪器是用于高温粘度测量的强大而准确的工具.
- 该仪器提供了诸如高吞吐量,低样本体积要求和成本效益高的样本容器等优势.
- 这项技术消除了对校准液体的需求,简化了在极端温度下对各种材料的粘度测量过程.
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