| 张金凤,张庆河,乔光全.水体紊动对黏性泥沙絮凝影响研究[J].水利学报,2013,44(1): |
| 水体紊动对黏性泥沙絮凝影响研究 |
| The effects of turbulence on flocculation of cohesive sediments |
| |
| DOI： |
| 中文关键词: 均匀各向同性紊流 黏性泥沙 絮凝 紊动剪切率 格子玻尔兹曼方法 |
| 英文关键词: homogenous isotropic turbulence cohesive sediment flocculation turbulent shear rate Lattice Boltzmann method |
| 基金项目: |
|
| 摘要点击次数: 2992 |
| 全文下载次数: 788 |
| 中文摘要: |
| 紊动水流中黏性泥沙絮凝沉降对河口海岸黏性泥沙输送过程起着十分重要的作用。建立了均匀各向同性紊流中黏性泥沙絮凝沉降的三维格子玻尔兹曼数学模型，模拟不同紊动剪切率对黏性泥沙絮凝过程的影响。模拟结果表明：随着紊动剪切率的增加，计算区域内絮团形成所需的时间先减少后增加，黏性泥沙沉降速度也呈现先减小后增大的趋势，剪切率的转折点在200s-1左右，与已有观测结果一致。模拟结果反映了低强度水体紊动对絮凝有促进作用而高强度水体紊动对絮凝有抑制作用。 |
| 英文摘要: |
| The flocculation and settling of cohesive sediment in turbulence play an important role on the cohesive sediment transport in estuaries and coastal waters. A three-dimensional numerical model of settling and flocculation of cohesive sediment in the homogenous isotropic turbulence using lattice Boltzmann method is developed to investigate the effects of turbulence on the flocculation phenomena of cohesive sediment. It can be seen that with increasing shear rate the start time of the floc formation will be earlier firstly and then be later. Furthermore， it also can be concluded that with increasing shear rate the settling velocity of flocs first increases， then decreases. The turning point of shear rate is 200s-1， which is consistent with the observation. Simulation results show that the low turbulent shear rates have role in promoting on flocculation processes and the opposite trend at high shear rates properly. |
|
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |