水利水电科技进展2018，Vol.38Issue(4)：21-27,7.DOI:10.3880/j.issn.1006-7647.2018.04.004
地形突变条件下异重流运动失稳规律
Instability principles of density current under the condition of rapidly varying topography
摘要
Abstract
The instability principles of density current are less studied at present,but they are significant to the life-span extension and the optimal operation of reservoirs.Mike3 was used to construct the three-dimensional numerical model for density current,which includes a hydrodynamic model,a turbulence model and the sediment transport diffusion equation.The model was validated by a flume experiment and the results show that the modeled sediment concentration agrees well with the measured value.Based on the model,the instability principles of turbidity current under the condition of rapidly varying topography is studied by using the Zipingpu Reservoir as an example.The influence of the bottom obstacle and the abrupt widening of the cross section on density current were analyzed and the discriminant conditions for the instability of density current are obtained for the two situations respectively.For the situation of bottom obstacle,the discriminant conditions are(1)the velocity of the density current decreases,(2)the sediment concentration decreases,and(3)the thickness of the front and the density current decreases.For the situation of abrupt widening at the cross section,they are(1)the velocity of the density current decreases,(2)the vertical profiles of sediment concentration change from parabolic distribution to logarithmic distribution,and(3)the thickness of the density current decreases.关键词
异重流/运动失稳/地形突变/水槽试验/三维数学模型/紫坪铺水库Key words
density current/flow instability/rapidly varying topography/flume experiments/three-dimensional numerical model/Zipingpu Reservoir分类
建筑与水利引用本文复制引用
宋以兴,李嘉,安瑞冬,严忠銮,徐亚亚..地形突变条件下异重流运动失稳规律[J].水利水电科技进展,2018,38(4):21-27,7.基金项目
国家自然科学基金(51579164,91547211) （51579164,91547211）
