Study On Filter Performance Of Disc Filter And Optimization Of Disc Flow Channel

As the micro-irrigation emitter is easy to be blocked, so the filter in micro irrigation is an important part in drip irrigation system. Disc filter is a new filter for micro irrigation in recent years. Further research on its hydraulic and filtration performance is of great significance for the development of the disc filter products. Through the experiment, the filter performance, filter efficiency and precision of the disc filter are analyzed. By using computational fluid dynamics, a 3D numerical model is established for the hydraulic performance of the disc, and the influence of the geometric structure of the disc on the hydraulic performance is simulated and analyzed.The filtration performance test results show that the increase of head loss of disc filters is increased in a non-proportion with the quantity of sand: in a certain amount of sand volume, the head loss surged suddenly, and quickly reaches or exceeds the safe pressure, after adding a small amount of sand. The size of sand has influence on the anti-clogging performance of the filter. Compared to the maximum cross section of the disc groove size, if the size of sand is too large, it is easily to be blocked from outside of the disc. While if the size of sand is smaller than the minimum cross section of the disc groove size, the sand can through the disc easily. Therefore, in the choice of disc filter, should consider the sand and disc groove size. The installation direction of the disc filter has little influence on the hydraulic performance, but has a great influence on the filter performance. The filter performance of the disc filter is better, when it is upward installed. On basis of the filtering efficiency of disc filters, the relationship between disc filter precision(M) and the inscribed circle diameter(D) of the minimum groove section is M:D≈1:1.2.A 3D numerical model of the hydraulic performance of linear disc is established. The deviation between simulation results and the measured value is 8%, which indicates the simulation results with a high reliability, and numerical simulation can be used to study the hydraulic performance of disc filter. Under the conditions of clean water, when the disc groove section is isosceles triangle, maintain the inscribed circle diameter of the minimum groove section(disc filter precision). The tilt angle of groove and radius direction has little effect on the head loss. The base corner of the minimum groove section has effect of the flow capacity. In the base corner of 60 degrees, shows the minimum flow capacity and maximum head loss. The head loss of disc was negatively correlated with disc width. In order to reduce the head loss of the disc, the groove size of outside radius should be increased appropriately.