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Flow measurement facilities in channels are the basis for charging agricultural water according to water consumption. Because the number of small channels in irrigation districts is large, there are many sections to be measured. Therefore, mobile flow measurement facilities are recommended to measure the discharge. However, the existing mobile water measuring facilities are still not suitable enough. Combining the advantages of mobile thin plate flumes and cylindrical flumes, a plate-column portable flume was developed. Based on the analysis of the mechanism of flow measurement for the flume, prototype tests and numerical simulations of the plate-column portable flume were carried out. And the flow measurement formula was established by using the dimensional analysis method. The results showed a good relationship between water depth and flow rates in plate-column portable flumes. The upstream backwater height was between 13.69cm and 1.85cm, the critical submergence was between 0.91 and 0.70, and the Froude number Fr at the upstream of the plate-column portable flume was less than 0.5. The plate-column portable flume had a smaller shape than the existing circular flume and the flume with a round head and a empennage, and had a higher portability and a slightly worse streamline distribution;its upstream backwater height was slightly larger and its critical submergence was slightly lower, but that still can meet the requirements of the flow measurement in the irrigation area. The plate-column portable flume had a high accuracy that the average relative error of which was only 2.07%, and had the prospect of generalization and application.