Eddy interaction model for turbulent suspension in Reynolds-averaged Euler–Lagrange simulations of steady sheet flow
Eddy interaction model for turbulent suspension in Reynolds-averaged Euler–Lagrange simulations of steady sheet flow
复制标题
稳态片流雷诺平均欧拉-拉格朗日模拟中湍流悬浮体的涡相互作用模型
DOI：
10.1016/j.advwatres.2017.11.019
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发表时间：
2018
影响因子：
4.7
通讯作者：
J. Calantoni
中科院分区：
文献类型：
--
作者：
Zhen Cheng;J. Chauchat;T. Hsu;J. Calantoni
摘要建立了一个考虑颗粒间相互作用的稳态薄层水流Euler-Lagrange泥沙输运模型（CFDEM-EIM），模型中湍流模型采用了低雷诺数修正的k− ω湍流封闭模型。为了模拟湍流对泥沙悬浮的影响，采用涡动相互作用模型（EIM）模拟了湍流涡与颗粒之间的相互作用。首先用稀悬浮液实验的测量值校准EIM。我们表明，涡动相互作用模型能够再现著名的劳斯轮廓悬浮泥沙浓度。模型结果被认为是敏感的系数，C 0，与沉积物的相互作用时间的选择。建议C 0= 3的值与稀释悬浮液中的测量浓度相匹配。校准的CFDEM-EIM被用来模拟轻质粗颗粒的稳定片流实验，并产生了合理的协议与测量的速度，浓度和湍流动能剖面。进一步的薄层流数值试验表明，当C 0减小到C 0< 3时，模拟对稀相区的悬沙量预测不足，对施密特数预测过高（Sc> 1.0）。在0.3和1.2之间的希尔兹参数范围内的额外模拟证实，CFDEM-EIM能够预测类似于经验公式的输沙率。基于输沙率和输沙层厚度的分析，EIM和由此产生的悬移质是重要的，当降落参数小于1.25。
Abstract A Reynolds-averaged Euler–Lagrange sediment transport model (CFDEM-EIM) was developed for steady sheet flow, where the inter-granular interactions were resolved and the flow turbulence was modeled with a low Reynolds number corrected k− ω turbulence closure modified for two-phase flows. To model the effect of turbulence on the sediment suspension, the interaction between the turbulent eddies and particles was simulated with an eddy interaction model (EIM). The EIM was first calibrated with measurements from dilute suspension experiments. We demonstrated that the eddy-interaction model was able to reproduce the well-known Rouse profile for suspended sediment concentration. The model results were found to be sensitive to the choice of the coefficient, C 0, associated with the turbulence-sediment interaction time. A value C 0= 3 was suggested to match the measured concentration in the dilute suspension. The calibrated CFDEM-EIM was used to model a steady sheet flow experiment of lightweight coarse particles and yielded reasonable agreements with measured velocity, concentration and turbulence kinetic energy profiles. Further numerical experiments for sheet flow suggested that when C 0 was decreased to C 0< 3, the simulation under-predicted the amount of suspended sediment in the dilute region and the Schmidt number is over-predicted (Sc> 1.0). Additional simulations for a range of Shields parameters between 0.3 and 1.2 confirmed that CFDEM-EIM was capable of predicting sediment transport rates similar to empirical formulations. Based on the analysis of sediment transport rate and transport layer thickness, the EIM and the resulting suspended load were shown to be important when the fall parameter is less than 1.25.
使用大涡模拟方法的稳定片流的欧拉两相模型
影响因子：
4.7
作者：
Cheng, Zhen;Hsu, Tian-Jian;Chauchat, Julien
通讯作者：
Chauchat, Julien
影响因子：
5.1
作者：
J. Chauchat;Zhen Cheng;T. Nagel;C. Bonamy;T. Hsu
通讯作者：
J. Chauchat;Zhen Cheng;T. Nagel;C. Bonamy;T. Hsu