Hydraulic performance and energy dissipation effect of pit structure flow channel emitter

摘要

In this paper, a drip irrigation emitter with new pit flow channels such as shunt, sharp turn, and confluence was constructed by the pit structure in the water transporting tracheid of bionic plant xylem. In order to study the hydraulic performance and energy dissipation effect of the pit flow channel, the geometric parameters of the pit flow channel were combined by simulation prediction and orthogonal test. The 25 sets of test schemes were carried out to test the hydraulic characteristics, and the Bernoulli equation was used to solve the structural loss coefficient. At the same time, the orthogonal test results were analyzed by the range and variance, and the regression model of geometric parameters and flow index was established. The results showed that the flow index of the emitter was 0.462~0.496, and its hydraulic performance was good. The structural loss coefficient under the pressure head of 5~25 m was 2120~6321, which showed that the energy dissipation effect was obvious. The order of influence of each geometric parameter on the flow regime was T>B>S>D>A, and the optimal scheme was T0.18B2.2S2.2D0.2A4. The regression coefficient of the model was significant. The value of the F statistic was 16.670, corresponding to the significance level Sig.=0<0.05, and the error of the experimental and simulated values of the flow index was less than 5%, which proved the accuracy and reliability of the regression model. This paper provides a new idea for agricultural drip irrigation control technology.