Research Of Hydraulic Performance For Combined Labyrinth Rrrigation Device

Water is one of the indispensable main materials of our human life and is essential for the development of the country and social progress.China’s huge population base makes China’s per capita water resources less than 1/4 of the world’s average level,ranking the last in the world,severe water shortage,about 2/3 of large and medium-sized cities are facing severe water shortages.At the same time,due to widespread water pollution and waste of water resources,China’s water resources are in a tight supply and demand situation.Therefore,China must vigorously develop agricultural water-saving irrigation.Drip irrigation is the most water-efficient irrigation technology in all water-saving irrigation technologies and is widely used.Compared with surface irrigation,its water-saving capacity can be as high as 80%,compared with sprinkler irrigation,it can save up to 40%and save energy by 60%.See the advantages of drip irrigation.In the drip irrigation system,the irrigator is the most important component,and its internal flow channel structure form is also the key to affecting the hydraulic performance of the irrigator.It has a great impact on the anti-clogging ability,irrigation uniformity and service life of the drip irrigation system influences.Therefore,finding a kind of irrigation device with better hydraulic performance is the key issue of our current research.This article combined with the dripper clogging problem in the renovation project of the Wusu water-saving irrigation demonstration base in Taiyuan City,combined with the research direction of the instructor,decided to further study the dripper flow channel structure,and proposed a drip with better hydraulic performance and anti-clogging performance.Head runner structure.In this paper,the FLUENT numerical simulation method is used to select a combination of single internal tooth structure and double internal tooth structure to form a combined labyrinth channel irrigation device based on the previous research.Under 6 pressure heads,there are 4 combination methods,respectively ABB,ABA,BAB,BAA(A is a single internal tooth structure,B is a double internal tooth structure),the cross-sectional dimensions of the toothless area are 1.5 mm*1.5 mm,1.7 mm*1.7 mm,2.0 mm*2.0 mm and 2.5 mm*2.5 mm,tooth height is 0.794mm,0.9mm,1.058mm,1.323mm,16 kinds of combined labyrinth channel sprinklers in total.Simulate the internal water flow condition,use the power function to fit the pressure and flow,get the pressure～flow curve,and get the corresponding flow coefficient k and flow state index x.To study the influence of different flow channel combination units on its hydraulic performance,the aim is to obtain a better labyrinth flow channel irrigation device structure.The following conclusions are obtained:(1)The flow rate of the combined labyrinth channel sprinkler increases with the increase of pressure;(2)When the cross-sectional size and structural parameters of the irrigator are fixed,the flow index of the combined irrigator structure of AAB and ABA increases with the increase of tooth height and cross-sectional size,while the combined irrigator of BAB and ABB structure With the increase of tooth height and cross-sectional size,the flow state index showed a trend of decreasing thickness first and increasing;(3)When the size and structural parameters of the irrigation device are fixed,the flow index of the combined ABB and BAB irrigation device structure is less than that of the combined AAB and ABA,so the hydraulic performance of the combined ABB and BAB combined labyrinth channel irrigation device is better;(4)When the section size and structural parameters of the irrigator are fixed,the flow coefficient of the four combined irrigator structures increases with the increase of tooth height and the size of the inlet section;(5)The discharge coefficient of the combination of AAB and ABA is almost the same,the discharge coefficient of the combination of BAB and ABB is almost the same,and the combination of AAB and ABA labyrinth channel is larger than that of BAB and ABB.Flow index,so the hydraulic performance of the combination of BAB and ABB labyrinth channel sprinklers is better;(6)The flow index and discharge coefficient of the labyrinth channel sprinklers with different combinations of 2.5mm*2.5mm at the toothless area are the largest,and the hydraulic performance is the worst;(7)The flow coefficient and flow index of the BAB combined labyrinth channel sprinkler with a cross-sectional size of 1.5mm*1.5mm and a tooth height of 0.794mm are the smallest,indicating that its hydraulic performance is superior;...