Study On Hydraulic Characteristics Of Anti-clogging Of Drip Irrigation Pipe Under Fertilization

As one of the most widely used high-efficiency water-saving irrigation technologies,water and fertilizer integrated drip irrigation technology has the advantages of water and fertilizer saving,can provide technical conditions for the realization of fine and efficient facility agriculture,and effectively promote the process of modernizing agricultural production.However,the clogging of the irrigation device in the drip irrigation system has become the bottleneck of the current application and promotion of drip irrigation technology.Therefore,studying the hydraulic characteristics of anti-clogging drip irrigation pipe to provide technical support for the application of drip irrigation technology is of great significance for promoting the application and promotion of drip irrigation technology.In this study,a short-period intermittent irrigation test method was adopted.For three different fertilizers of compound fertilizer,phosphate fertilizer and organic fertilizer,the temperature,operating pressure and fertilizer concentration factors were considered.A full test was carried out to study the influencing factors and changing rules of dripper clogging.The clogging mechanism of the dripper,and seeking a suitable threshold for the concentration of fertilizer to provide a theoretical basis for the actual field water and fertilizer integrated drip irrigation.The following main conclusions are obtained:1. The operating pressure has different clogging rules for different fertilizer drip irrigation drippers.When the irrigation times are the same,the compound fertilizer and phosphate fertilizer drip irrigation are used.The average relative flow rate and uniformity coefficient reach the maximum at a pressure of 50 k Pa.The smaller the operating pressure,the greater the average relative flow rate and uniformity coefficient.Pressure has no significant effect on clogging of the dripper.The clogging rate is negatively correlated with the operating pressure.The higher the operating pressure is,the lower the clogging rate is.When the operating pressure is reduced,the clogging position moves from the second half to the front half of the drip irrigation belt.2. The temperature is different for different fertilizer drip irrigation dripper clogging rules.Under the conditions of compound fertilizer and organic fertilizer drip irrigation,the increase in temperature can increase the average relative flow rate and uniformity coefficient;the clogging rate is negatively related to the temperature.The higher the temperature,the lower the clogging rate.As the temperature decreases,the clogged dripper develops towards the front part.Under the condition of phosphate fertilizer drip irrigation,the effect of temperature on dripper clogging is not significant.3. Operating pressure and temperature have an interactive effect on the clogging of compound fertilizer and phosphate fertilizer drip irrigation dripper.Under the condition of compound fertilizer drip irrigation,the effect of increasing temperature on the average relative flow rate,uniformity coefficient and clogging rate decreases with increasing pressure.Under phosphate fertilizer conditions,when the operating pressure is lower than 30 k Pa,the higher the temperature,the higher the clogging rate,the greater the decrease in average relative flow rate and uniformity coefficient,and the position of the clogging dripper develops toward the front of the drip irrigation belt with increasing temperature;When the operating pressure is higher than 40 k Pa,the effect of temperature on the dripper clogging is not significant.4. Reducing the fertilizer concentration can effectively reduce the risk of dripper clogging.Increasing the fertilizer concentration of compound fertilizer,phosphate fertilizer and organic fertilizer can reduce the average relative flow rate and uniformity coefficient;under the experimental conditions,the blocking rate is low at a concentration of 3 g/L,and the average relative flow rate and uniformity coefficient are the largest And the clogging rate is positively correlated with the fertilizer concentration.As the fertilizer concentration increases,the clogging position of the dripper moves from the rear to the front of the drip irrigation belt.5. The threshold of fertilizer concentration is different at different temperatures.The thresholds for the fertilizer concentration of the compound fertilizer at temperatures of 10?,20?,30?,and 40?are 4 g?L^-1,5 g?L^-1,7 g?L^-1,and 8g?L^-1,respectively;the phosphate fertilizers are 3.0 g?L^-1,2.5 g?L^-1,2.0 g?L^-1 and 2.0g?L^-1;organic fertilizers were 10.0 g?L^-1,16.0 g?L^-1,18.0 g?L^-1 and 20.0 g?L^-1,respectively.