| Canal water gauging technology is crucial for the sound management in irrigation region, improvement of economic benefit, fulfillment of program that charge by cubic of water, as well as the development of water-saving agriculture. Considering the areal variation like economic background, development level and hydraulic character in different irrigation regions, development of a flume measuring equipment featured by simple structure, convenient manipulation, high adaptability, few head loss, high measuring accuracy, and explicit flow calculation formula, is one of the critical means for scientific and efficient management of irrigation region, and has an important significance upon water-saving and sustainable development.Airfoil-shaped measuring flume is a brand-new equipment applicable to the characters of irrigation region in our country. The flow side of the measuring flume is made based on the shape of airfoil, and controlled by specific curvilinear equation. This flume boasts a simple structure, low cost and water stream can pass it smoothly. On the basis of the predecessors'research on this flume, analysis and further research of the application of it in rectangular canal is conducted in this dissertation by means of combination of entity model experiment and computational numerical simulation. Main research contents are as follows:(1) Explanation of measuring principle and structure form of airfoil-shaped measuring flume. Work out the flow calculation formula by dimensional analysis and double-logarithmic fitting.(2) Establish the airfoil-shaped measuring flume of various contraction ratios in indoor rectangular canal, by means of systematic experiment to analyze the hydraulic characters under circumstances of free discharge, like overflow capacity of flume, development and change of water jump and water surface profile, velocity distribution, extent of submergence and hammed water, etc. Afterwards the flow calculation formula shall be checked by the measured data so as to verify the accuracy of this measuring flume.(3) Set up numerical model for measuring flumes of various hydraulic parameters, and conduct numerical simulation for each flume in accordance with the features of liquid analysis software Fluent and Flow-3D to represent the flow process, and various hydraulic characters of that are analyzed and researched. (4) Through the comparison of the results calculated by software and data measured by model experiment, coupled with the discussion regarding the physical quantity which is difficult to handle and measure in the model experiment, to analyze the feasibility of research, design and optimization of airfoil-shaped measuring flume by means of numerical simulation, in a bid to provide technical reference and suggestions for the promotion of this flume in irrigation region.
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