Development and application of a new differential pressure flow-meter
Li Yanjun1,Yan Dengfeng2
(1.Technical and Research Center of Fluid Machinery Engineering of Jiangsu,Zhenjiang,Jiangsu 212013,China;2.Yangzhou University,Yangzhou,Jiangsu 225009,China)
Abstract： A new differential pressure flow-meter is developed by using the theory of flow around a circular cylinder.The special designed cylinder tube is used to obtain fluid pressure in the flow-meter.By measuring the fluid pressure difference between the total pressure hole against the flow and the side hole at specified angles,the point velocities and the average flow rate of cross-section are determined.In a certain range of flow angle around the cylinder tube,the flow pressure coefficient does not change with the Reynolds number,so the new flow-meter can be calibrated outside conduit but not in situ.The application is convenient and reliable,and the system uncertainty can be controlled within ±1.0%.The new flow-meters are applied to the single-pump flow test at the scene of No.1 and No.3 unit of Xietai Pumping Station in South-North Water Transfer East Route Project.The errors between the results of field test and conversion from model test were within 0.78 m3/s.The cylinder tubes of the flow-meters were inserted into the suction chamber before the pump impeller,and the flow measurement of large pump was achieved on the condition of no straight pipes.
李彦军， 严登丰. 一种新型差压流速流量计的研制与应用[J]. 排灌机械工程学报, 2009, 27(4): 251-254.
Li Yanjun1,Yan Dengfeng2. Development and application of a new differential pressure flow-meter. Journal of Drainage and Irrigation Machinery Engin, 2009, 27(4): 251-254.
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