Research On Flow Characteristics And Stability Hydraulic Geometry Of Vegetated River

The exploitation and utilization of river has produced a certain degree of economic efficiency and the great contribution for human has been made for economic prosperity. At the same time, some man-made natural disasters have been paid more and more attentions , so the research on hydraulic characteristics of the river in recent years has been put on the agenda. Considering the ecological environment, flood control, pollution prevention and control method, and in view of the perspective of the urban landscape as well as the national strategic plan for sustainable development, the research the hydraulic characteristics of river and making river reasonably repair and ecological reconstruction will become a general trend, because that is a kind of remediation measure for human to be done unreasonable exploitation, and it also will be the strong protection of river resources and sustainable model for better using river resources in the future.Based on the review of river characteristics research results now, the physical model test of hydraulic characteristics of compound river with vegetations in floodplain, dynamic width adjustment are carried out by this paper, a kind of grass named maidongcao is selected as model vegetation grown. The flow field and river topographic survey are obtained by means of ADV, portable flow meter instrument and interface mete, the effect of floodplain vegetations on width adjustment is studied.This paper comprehensively summarizes the achievements about flow characteristics of vegetated river and river width dynamic adjustment; carries out the systemic model tests of mobile bed with vegetated floodplain, measures the velocity distribution and width adjustment process, and conductes the theoretic research . The rough formula of vegetated river is obtained by means of former research results when considered the vegetation density and its effect on width adjustment. On the basis of conservation of energy, this paper uses Shannons entropy theory to explain the influence factors deal with the sandy river bed stability by theoretical analysis, the concept of Shannon entropy is considered for setting up a theoretical relation of hydraulic geometry used the maximum entropy principle and variation approach, so that a stable relation of hydraulic geometry dealt with the river cross-section width, average water depth and time process is derived. In order to verify it's reasonable, many terrain data of border-related information at the up and down points in this compound model river are measured and analyzed, comparing the experimental data of physical mode with calculate ones at different time may find that both are a good agreement, it further proves that width adjustment of compound river keeps to energy dissipation principle and entropy law, which enriches the research findings of such subjects;Based on the foundation of explaining about ecological river, and considered the factors affected ecological river natural function and social function,the current research situation is analyzed;In view of the problems such as ecological restoration technology, water quality measure target and so on, the degree and trend of technology development in application nowadays are presented in this paper.