Research On Numerical Simulation Of Hydraulic Characters And Somatotype Analogy For Airfoil-shaped Measuring Flume

Channel water delivery is the main form of Chinese farm irrigation.However,some irrigated areas of China have no relevant water measuring facilities,or some water measuring facilities can not be used normally due to the large measurement error.Given to the poor consciousness of saving water of Chinese,there is severe phenomenon of water resource waste in China.The slot-type water-measuring facilities,with the advantages of economical,reliable and stable etc,is more suitable for large application of irrigated area.Currently,the measuring flume not only can measure water in channel,but also can measure the rain flow and sewage flow to provide reference for sewage treatment plant.Given the advantages of small head loss,smooth rinsing,simple structure and high flow-measuring precision,the streamlined airfoil-shaped measuring flume is suitable for the environment of Chinese irrigated area and satisfies the precise requirement of water-measuring precision.As a result,comprehensive and profound research shall be conducted toward such measuring flume.This thesis analyzes the structural form and flow-measuring mechanism of the measuring flume,and conducts numerical simulation toward the hydraulic characteristics of classical and optimized airfoil-shaped measuring flume.Then,analogy analysis is conducted.Following are conclusions:(1)3D models of airfoil-shaped measuring flume of rectangle channel are established,and simulating calculation is conducted under 70 kinds of working conditions.Meanwhile,the established model,the selected parameters and fluent calculation are verified and the results have higher reliability.(2)It is found through research that the shrinkage ratio within 0.50~0.60 is more reasonable under the condition of not affecting flow-measuring precision.(3)Analogy results of the two somatotype: the maximum speed of the optimized somatotype is more closer to the throat than the classical one;the upstream waterline of the optimized somatotype is slightly lower than the classical one while its downstream waterline is higher than the classical one,which shows that the submergence ratio of the optimized somatotype is larger than the classical one and the optimized somatotype has larger free discharge range;the maximum Froude number of the optimized somatotype is more smaller than the classical one;the head loss of the optimized somatotype is smaller than the classical one generally;the flowmeasuring precision of the optimized somatotype is relatively higher than the classical one,which confirms to other conclusions.