| The continuous self-cleaning screen filter has the technical advantage of simultaneous filtration and flushing.The combination of field experiment,laboratory experiment and Fluent numerical simulation is used to carry out experimental research on the filtration performance of the continuous self-cleaning screen filter,which is of great significance to improve the filtration caPacity and efficiency of the drip irrigation system and ensure the normal operation of the drip irrigation system.The main research results are as follows:(1)Field experiment was carried out,in the clear water experiment,with the gradual increase of the water level difference between the inlet pool and the outlet pool,the filter flow showed a trend of gradual increase,and the speed of the filter cartridge showed a trend of gradual decrease.In the turbid water experiment,when the mesh number of filter screen and sediment rate increased,the filter flow rate and the speed of the filter cartridge decreasd,and the water level difference between the two pools increasesd.(2)In order to further study the filter operation characteristics,the laboratory filtration experiment device was designed,and according to the experimental data,multiple regression analysis was used to reveal the quantitative relationship between the head loss of the filter screen,the water level difference inside and outside the filter,the sediment rate and the filtration time,and the filter filtration caPacity model was established.(3)Based on the filter caPacity model,the filter inlet boundary conditions were set,and the simulated flow values of three mesh sizes and three turbulence models were obtained by using Fluent software,and the 0.03m mesh size and standard k-ε model were determined and selected through comParison and analysis with field test data,which had high calculation accuracy,and the relative error between the simulated flow value and the experimental value was between 3.04%～7.2%,which provided a basis for numerical simulation.(4)Through numerical simulation,it was found that the changes of mesh number,filter cartridge length and cartridge diameter had a great influence on the internal pressure field and velocity field of the filter,but had little effect on the turbulent kinetic energy field.Cartridge length had a greater effect on filter flow than cartridge diameter.(5)Simulation of the filter with 120 mesh screen showed that the cartridge length and diameter values of 1m and 1.5m were more appropriate;the cartridge speed rised from 3r/min to 6r/min and the filter flow rate riseed from 162.85m3/h to 214m3/h,indicating that increasing the cartridge speed can improve the filter’s filtration performance. |
