通过影图法确定具有各种易斯数以及正负索雷特系数的二进制流体混合物的扩散率
W Wu1, P S Schmidt1, M Piszko1
1Institute of Advanced Optical Technologies - Thermophysical Properties (AOT-TP), Department of Chemical and Biological Engineering (CBI) and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Paul-Gordan-Straße 8, 91052 Erlangen, Germany.
The Journal of chemical physics
|August 18, 2023
概括
本研究展示了如何使用非平衡波动在二元混合物中测量扩散和热扩散性. 阴影图法准确地确定了这些属性,即使有小的向导,对于各种混合物和条件.
科学领域:
- 热力学是一种热力学.
- 流体动力学 流体动力学
- 物理化学 物理化学
背景情况:
- 精确测量传输特性,如扩散和热扩散性,对于理解流体行为至关重要.
- 非平衡热力学为分析复杂系统中的动态波动提供了一个框架.
- 影图法提供了一种非侵入性的光学技术,用于研究流体动力学.
研究的目的:
- 为了证明Fick扩散系数 (D11) 和热扩散率 (a) 在二元混合物中的可访问性.
- 调查影图法在不同条件下确定这些属性的适用性.
- 为了比较影像图衍生的扩散度与文献值和其他实验技术.
主要方法:
- 使用影图光学方法分析非平衡波动动态.
- 对二进制混合物同时确定D11和a.
- 在广泛的温度 (298.15473.15 K) 和压力 (0.525 MPa) 范围内进行测量.
主要成果:
- D11和a被确定为混合物,包括二环基甲/二甲,n-hexane/二氧化碳,1-hexanol/二氧化碳和甲/.
- 对于易斯数 (Le = a/D11) 来说,成功地确定了D11和a,下降到大约5.
- 阴影图方法显示,由于模式合效应,在Le ≈ 5确定"a"时存在局限性,但D11的确定对于Le ≥ 5仍然可靠.
- 对于非平衡度波动的纯扩散行为模型的有效性得到了证实,即使有溶液向.
结论:
- 阴影图法是一种可行的技术,用于测量二元混合物的扩散和热扩散性.
- 该方法的准确性取决于易斯数和辅向的存在.
- 进一步对异体动态光散射等技术进行验证,证实了确定的扩散率的可靠性.
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