1.Key Laboratory of Fluid and Power Machinery, Ministry of Education,Xihua University, Chengdu, Sichuan 610097, China
2. Sichuan Southwest Vocational College of Civil Aviation, Chengdu, Sichuan 610039, China
Abstract：For large-diameter irregular square pipes with a diameter exceeding 1m, where the length of the curved section is short and there are no long straight pipes before and after, and the flow field inside the pipe is complex, there is a need for accurate measurement of the pipe flow. In this regard, a numerical simulation analysis is conducted, proposing a mean velocity evaluation method based on the coefficient of variation. This method selects multiple points that best represent the average flow velocity of the pipe, determining the insertion depth of the sensors and the weight coefficients of multiple measuring points. A calculation formula is then derived, with the cross-sectional average velocity as the function and the velocity values at multiple points in the flow field as the independent variable.Flow measurement experiments are conducted on a wind tunnel test bench, and the calculated values obtained from the formula derived through numerical analysis are compared. The relative error within the full range is less than 0.54%.
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2024, Vol. 45 
