Pressure Compensating Emitter Numerical Simulation Of Flow Field And Analysis Of Compensation Component

Drip irrigation is one of the most effective methods in water-saving irrigation.Emitter is the most important equipment in drip irrigation system.Its capability directly influences the quality and cost of drip irrigation. Thus, the study on the hydraulic performance and ability of emitters has important significance.The pressure compensating emitters which have the advantages of constant flow under the change of pressure,anti-clogging and self-cleaning performance have been the hotspot in research in the world.A CFD model,which was used to simulate the flow field within emitter,was established and calculated fluid-solid coupling by the mercantile ANSYS software.To verify the CFD numerical simulation model,the results were compared with traditional emitter's hydraulic performance tests.It shows that insteading of the traditional hydraulic performance tests of emitters,using the CFD numerical simulation method studies the flow field within emitter is feasible. Simulating flow mostly were bigger than fact flow,but the windage was under 10%. Numerical visualization can reduce the times of experiment,and can realize low cost and high efficiency development of high quality emitter. The experiment and numerical simulation are carried out with orthogonal design method,both of them are used to get the hydraulic performance data of online pressure compensating emitters.Three main factors were selected,the size of dividing grid,the computational physics model and the solving treatment mode,which have significant influence on the CFD simulation precision.Using the above three factors,an orthogonal experiment had been established to simulate the effects of CFD precision.According to the simulation results,the significance of these factors'effects,from height to low,is the size of dividing grid, the computational physics model and the solving treatment mode. Among these influencing factors, the level of the best combination of factors is the transient solving treatment mode,0.15 mm grid size and laminar flow model.Though theory analysis,single factor and orthogonal experiments, studied the effect of elastic membrane parameters on hydraulic performance of emitters thickness and hardness. In certain flow field structure, obtained the linear regression equation of pressure compensating emitter nominal flow and elastic membrane of thickness and hardness. Guiding significance for development of pressure compensating emitter.