River ice is an important hydraulic element in temperate and polar environments and would affect hydrodynamic conditions of rivers through changes both in the boundary conditions and the thermal regime. The river bend...River ice is an important hydraulic element in temperate and polar environments and would affect hydrodynamic conditions of rivers through changes both in the boundary conditions and the thermal regime. The river bend has been reported as the common location for the initiation of ice jams because the water flow along a river bend is markedly affected by the channel curvature. In this article, the experimental studies about the ice accumulation in a river bend are reviewed. Based on experiments conducted so far, the criteria for the formation of ice jams in the river bend, the mechanisms of the ice accumulation in the river bend and the thickness profile of the ice accumulation in the river bend are discussed. The two-equation turbulence model is used to simulate the ice accumulation under an ice cover along a river bend. A formula is proposed for describing the deformation of the ice jam bottom. Our results indicate that all simulated thickness of the ice accumulation agrees reasonably well with the measured thickness of the ice accumulation in the laboratory.展开更多
In this article, based on the theory of two-phase flow and laboratory data, a three-dimensionally model is developed to simulate the floating rates of frazil ice particles in water under covered condition. The Lagrang...In this article, based on the theory of two-phase flow and laboratory data, a three-dimensionally model is developed to simulate the floating rates of frazil ice particles in water under covered condition. The Lagrangian trajectory method is used in the three dimensional simulation for floating rates of fxazil ice particles along a 180° bend channel. The velocity profiles in longitudinal and transverse directions, the turbulence intensity, and the residual pressure are simulated. Under the condition of gravitational similarity, the simulated floating rates of frazil ice particles in the model bend channel and the prototype bend channels are compared. Results indicate that the profiles for floating rates of ice particles for flows in the model channel are similar to those in the prototype bend channels. The simulated floating rates of ice particles are clearly higher along the convex bank than along the concave bank at each cross section. For the prototype bend channel in a large model scale, the variation of floating rate across each cross section is relatively small.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50979021)supported by the Scientific Research and Development fund of Hefei University of Technology (Grant No. 2010HGXJ0064)
文摘River ice is an important hydraulic element in temperate and polar environments and would affect hydrodynamic conditions of rivers through changes both in the boundary conditions and the thermal regime. The river bend has been reported as the common location for the initiation of ice jams because the water flow along a river bend is markedly affected by the channel curvature. In this article, the experimental studies about the ice accumulation in a river bend are reviewed. Based on experiments conducted so far, the criteria for the formation of ice jams in the river bend, the mechanisms of the ice accumulation in the river bend and the thickness profile of the ice accumulation in the river bend are discussed. The two-equation turbulence model is used to simulate the ice accumulation under an ice cover along a river bend. A formula is proposed for describing the deformation of the ice jam bottom. Our results indicate that all simulated thickness of the ice accumulation agrees reasonably well with the measured thickness of the ice accumulation in the laboratory.
基金supported by the National Natural Science Foundation of China (Grant No.50979021)supported by the Hefei University of Technology (Grant No.GDBJ2008-020-Seed Grant for Ph D)
文摘In this article, based on the theory of two-phase flow and laboratory data, a three-dimensionally model is developed to simulate the floating rates of frazil ice particles in water under covered condition. The Lagrangian trajectory method is used in the three dimensional simulation for floating rates of fxazil ice particles along a 180° bend channel. The velocity profiles in longitudinal and transverse directions, the turbulence intensity, and the residual pressure are simulated. Under the condition of gravitational similarity, the simulated floating rates of frazil ice particles in the model bend channel and the prototype bend channels are compared. Results indicate that the profiles for floating rates of ice particles for flows in the model channel are similar to those in the prototype bend channels. The simulated floating rates of ice particles are clearly higher along the convex bank than along the concave bank at each cross section. For the prototype bend channel in a large model scale, the variation of floating rate across each cross section is relatively small.
