Firstly, three kinds of visualization techniques, four kinds of test models, and tracer particles were summarized. Then, the characteristics, advantages and disadvantages of those techniques, models and tracer particles were analyzed. Based on experimental results for water flow characteristics in emitters available so far, an experimental method for measuring the whole flow field in an emitter was proposed by integrating a transparent plane model which has the same scale as the real emitter, PIV and planar laser induced fluorescence(PLIF). A series of measurements in water flow characte-ristics in the emitter were realized under various pressures and shapes of flow channel by means of a unique design where a microscope objective lens was refitted into a CCD camera to allow the whole field to be mapped successfully. Based on review of existing experiments on particles transport characteristics in emitters, a quasi-three-dimensional measurement method for the whole field was proposed by integrating unit segment model, PIV and PLIF. Through observing the motion characteristics of particles in the emitters with different diameters, it was confirmed that there is the similarity in the characteristics between the prototype and the transparent model. The velocity distribution in a cylindrical emitter was measured by using this method and the particles transport characteristics in the emitters with three kinds of typical shapes of flow channel are observed. In future, the particle motion observation needs to be improved by using digital particle image velocimetry(DPIV); the three-dimensional measurement of whole field needs to be explored. It is necessary to conduct solid-liquid-gas multiphase flow simulations by using computational fluid dynamics(CFD)approach as well.
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