Two-phase flow analysis and experimental investigation of micro-PIV and anti-clogging for micro-channels of emitter

In order to visually study the real flow status of water mixed with sand escaped from filtering in the labyrinth channel of irrigation emitter, and to discuss some researches on the clogging mechanism of the labyrinth channel, aiming at complex and small labyrinth-channel emitters’ structure (the size is about 1mm), the common used rectangular and zigzag channels were selected to perform the Computational Fluid Dynamics(CFD) analysis of liquid-solid flow according to the two-phase theory. The water flow velocity, path line, the particle tracks and concentration of sand in labyrinth channel were obtained. Through the anti-clogging analysis, the main reason of emitter clogging is low-velocity and stagnant areas existing in the labyrinth channel. Then based on flow visualization technology—micro-PIV (Particle Image Velocimetry), the micro-PIV experimental bed was established, and the two-phase flow field in labyrinth channel was measured. Accuracy of CFD analysis results was tested with short period clogging experiment. Finally, through short period clogging experiment analysis, the optimal structural parameters of channels were obtained.