Abstract:To improve the uniformity of irrigation system and the design precision level of emitters,this study using a 3D camge measurement system(MCS-60)measured the structural parameters of channels in twenty-five combinations(from seven cylinder emitters and four pipe thickness).The hydraulic performances of the combinations were also tested by an automatic testing platform.The curves of the flow and pressure,flow rate coefficient and flow index were obtained.The results show that the flow rates of the same emitters can varied up to 20% with polypropylene (PE)pipes of different wall thickness.The PE pipe thickness affected the flow rate coefficients greatly,and the flow index to a less degree.The width of the emitter flow path was another factor for the influence of the PE pipe wall thickness.The more the width of the flow path,the bigger the change caused by pipe wall thickness.