| The pressure compensation emitter can keep the flow rate stable within a certain pressure range,has high water utilization efficiency,and has the effect of saving water and increasing production,and is widely used.The elastic sheet and the flow channel structure are the main components of the pressure-compensated emitter,which have a great influence on the hydraulic performance of the emitter.However,there are few studies on the mathematical relationship between the elastic sheet and the flow channel structure and the hydraulic performance of the emitter,and it is impossible to establish an effective pressure compensation emitter structure design method according to the existing research results.In order to find out the relationship between the structural parameters of the elastic sheet and the flow channel and the hydraulic performance of the emitter,and to promote the establishment of the scientific design method of the pressure compensation emitter in my country,the elastic sheet and the flow channel are studied using the sample test method in this paper’s hydraulic performance test.The influence of structural parameters on the emitter’s hydraulic performance was established,and a mathematical relationship between the structural parameters of the elastic sheet and the flow channel and the emitter’s hydraulic performance was established;the emitter flow prediction was constructed using a combination of fluid-structure coupling numerical simulation and dimensional analysis method.The mathematical model of serves as a foundation for the rapid design and development of pressure-compensated emitters that follow.The main conclusions of this study are as follows:(1)The hardness and thickness of the elastic sheet significantly affect the hydraulic performance of the emitter(P<0.01),and the effect of the hardness of the elastic sheet is greater than that of the thickness.The hardness and thickness of the elastic sheet can effectively adjust the flow rate of the emitter.When the hardness of the elastic sheet is 50 HA,the hydraulic performance of the emitter is optimal,and the thickness of the elastic sheet is larger,and the compensation performance of the emitter in the high pressure range is better.The coupling effect of the hardness and thickness of the elastic sheet affects the hydraulic performance of the emitter,and there is an appropriate hardness and thickness,so that the emitter has the smallest flow index and the largest compensation interval.The mathematical relationship between the hardness and thickness of the elastic sheet and the hydraulic performance of the emitter is established,and the experimental verification deviation is less than 5%,which can provide a reference for the rapid selection of suitable elastic sheet characteristic parameters for the pressure-compensated emitter.(2)The width of the small groove,the depth of the small groove,the height of the boss,the diameter of the water outlet and the diameter of the boss have a significant effect on the hydraulic performance of the emitter(P<0.01).The width of the small groove has an obvious influence on the compensation interval.The width of the small groove is 0.40 mm,and the compensation performance of the emitter is better in the high pressure stage;the depth of the small groove has a significant effect on the flow state index.Under the condition of low pressure irrigation,it is recommended that the depth of the small groove should not be greater than 0.2mm;The height of the boss can effectively adjust the flow rate of the emitter.If the height of the boss is greater than 0.5 mm,the emitter has no compensation effect;when the diameter of the water outlet increases,the flow rate of the emitter increases.When the diameter of the water outlet is greater than 1.2 mm,the compensation performance of the emitter decreases;When the diameter of the table increases,the starting pressure of the emitter decreases,the compensation interval increases,and the flow rate of the emitter changes less.The interaction among the width of the small groove,the height of the boss,the depth of the small groove and the diameter of the water outlet significantly affected the hydraulic performance of the emitter(P<0.01).The mathematical relationship between the structure parameters of the flow channel and the hydraulic performance of the emitter was established,and the experimental verification deviation was less than 7%,which can provide a reference for quickly determining the appropriate structure parameters of the emitter.(3)The joint action of the elastic sheet and the flow channel structure parameters has a significant effect on the hydraulic performance of the emitter(P<0.01);through the orthogonal test,the width of the small groove is 0.4mm,the depth of the small groove is 0.15 mm,and the height of the boss is 0.3 mm.,When the diameter of the water outlet is 1.2 mm,the diameter of the boss is 4.0 mm,the hardness of the elastic sheet is 50 HA,and the thickness of the elastic sheet is 1.0 mm,the hydraulic performance of the emitter is the best,the flow index is 0.006,and the compensation interval is 240 k Pa;The mathematical relationship between the structural parameters of the chip and the flow channel and the hydraulic performance of the emitter,the experimental verification deviation is less than 7%,which can accurately predict the hydraulic performance of the emitter,and provide a certain reference for the rapid design of the subsequent pressure-compensated emitter.(4)Through the combination of fluid-structure interaction numerical simulation and dimensional analysis,a mathematical model of pressure-compensated emitter flow prediction is constructed,which can directly predict the flow of pressure-compensated emitter with different working pressures and different geometric parameters.A emitter with better performance is designed,the flow index is 0.10,the starting pressure is 57 k Pa,the compensation interval is 220 k Pa,and the emitter flow is 2.09 L/h,which meets the design requirements of the pressure-compensated emitter.The method has a good design effect,which is of great significance to improve the research and development efficiency of pressurecompensated emitter and reduce the research and development cost. |
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