| The amount of irrigation water irrigation management and irrigation technology is animportant means of saving. Type of water tank building is currently used amount of irrigationwater facilities. In our country, increasing scarcity of water resources and a larger proportionof irrigation water is an important issue. Proposed amount of water efficient irrigationtechnology viable irrigation development is an important task. This paper summarizes thestatus of irrigation water measurement technology at home and abroad several common flumetechnologies. On this basis, a novel combination of type flume and its pilot study. Combinedflume is to adopt a cross-section of circular and linear tangent model to raise the water levelretaining flow measurement flume. Water flow through the constriction formed when bothsides of the critical flow, can produce a stable water level-discharge relationship. In order toanalyze the amount of argumentation combination flume water performance and feasibility ofthe application, we use a combination of five different sizes of type flume model tests.Depending on the flow contraction ratio obtained under different experimental data, obtainedin a rectangular channel combination flume in the free out of the flow, the water level of thestream-flow formula. On the analysis of the dimensionless type and fitting the experimentaldata，the non-dimensional style can be drawn in a different state of contraction ratiocombination flume relative critical depth KC/BCand relative upstream water depth H/BCinlogarithmic coordinates with a more good linear relationship. So KC/BCand H/BCfunctiontype can be drawn. Through the validation of the test results, we can see that using thismethod to establish the dimensionless flow equations satisfy harmony. Dimensional analysisestablished by the flow equation flow measurement accuracy. The average relative error offlow was2.16%, to meet regulatory requirements. Combination of the flume criticalsubmergence degree is higher and Critical submergence degree and the shrinkage ratio andflow rate has a certain relationship. The results show that, in this experiment the5selectedshrinkage ratio within the range of the highest critical submergence0.85. Thus ensuringcombined flume flow in the free state of the work. By analyzing the experimental data can be drawn, the amount of sink combination Froude number Fr contraction ratio ε only with flowrate Q for nothing. And the Froude number Fr contraction ratio ε with the increase. In thisselected five kinds of contraction ratio within the range of the amount of the sink combinationFroude number Fr is less than0.45, to meet the flume flow measurement accuracy. Throughthe rectangular channel right combination flume tests as well as the amount of sinkparameters were analyzed, we can draw the following conclusions: Combined water tank hasa certain amount of flow measurement accuracy, the amount of water to meet the irrigationrequirements; resulting water-flow formula simple, easy to calculate in practice;combination flume critical submergence simple structure and a high degree of ease ofconstruction, the actual amount of irrigation water to facilitate the operation. So thecombination flume rectangular channels can be used as the amount of water flowmeasurement devices, and has good application prospects. Currently, the combination is stillat a preliminary amount of flume test phase. Only the rectangular channels studied test databelow normal. Next to the new flume can be used in the current irrigation channels andtrapezoidal channels U-test study with field tests. |
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