Impact of horizontal plug-in flow meterson the velocity field-An experimental study
WANG Hao1, CHEN Huai2, LI Danxun1, WANG Xingkui1
1. State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China;
2. State Key Laboratory of Hydrology, Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing 210029, China
Abstract：Horizontal plug-in flow meters disturb the velocity fields when deployed to measure rates flow. The spatial extent of such disturbances has been experimentally studied here on a simplified flow meter model. The Pitot tube used as the flow model was placed horizontally in the water flow with instantaneous two-dimensional velocity fields also measured by particle image velocimetry (PIV). Analysis of the spatial variations of the velocity fields in front of the model shows that the streamwise velocity increases with the distance from the model nose and gradually approaches that of the incoming flow with the spanwise velocity, turbulent intensities, and Reynolds stresses decreasing with the distance. The streamwise velocity requires the longest distance to recover from the disturbance with the turbulent intensity requires the shortest distance. The spatial extent of the disturbance is proportional to the flow meter diameter.
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2016, Vol. 56 
