RMIT University, Chemical, and Environmental Engineering, School of Engineering, Melbourne, Australia.
LIST, Environmental Research and Innovation Department, Belvaux, Luxembourg.
Sci Total Environ. 2018 Feb 1;613-614:1031-1036. doi: 10.1016/j.scitotenv.2017.09.206. Epub 2017 Sep 22.
Appropriate sewage sludge rheological models are essential for computational fluid dynamic simulation of wastewater treatment processes, in particular aerobic and anaerobic digestions. The liquid-like behaviour of sludge is well documented but the solid-like behaviour remains poorly described despite its importance for dead-zone formation. In this study, classical Kelvin-Voigt model, commonly used for sludge in literature, were compared with fractional derivative Kelvin-Voigt model regarding their predictive ability for describing the solid-like behaviour. Results showed that the fractional Kelvin-Voigt model best fitted the experimental data obtained from creep and frequency sweep tests. Whereas, classical Kelvin-Voigt could not fit the frequency sweep data as this model is not a function of angular velocity. Also, the Kelvin-Voigt model was unable to predict the creep data at low stresses.
适当的污水污泥流变模型对于废水处理过程的计算流体动力学模拟至关重要，特别是好氧和厌氧消化。污泥的液态行为已有充分记录，但尽管其对死区形成很重要，但固态行为仍描述不足。在这项研究中，将文献中常用的经典 Kelvin-Voigt 模型与分数导数 Kelvin-Voigt 模型进行了比较，以评估它们描述固态行为的预测能力。结果表明，分数 Kelvin-Voigt 模型最适合描述从蠕变和频率扫描测试中获得的实验数据。然而，经典 Kelvin-Voigt 模型不能拟合频率扫描数据，因为该模型不是角速度的函数。此外，Kelvin-Voigt 模型无法预测低应力下的蠕变数据。
