TY - JOUR ID - TI - Comparison of Discharge Equations for Radial Gate in Large Scale Canal AU - cui wei AU - wu xin AU - chen wenxue AU - mu xiangpeng VL - IS - PB - SP - EP - PY - JF - Journal of Irrigation and Drainage JA - UR - http://www.ggpsxb.com/jgpxxben/ch/reader/view_abstract.aspx?file_no=202012050000001&flag=2 KW - 水力学;南水北调中线工程;弧形闸门;淹没出流 KW - hydraulics; the middle route of South-to-North Water Diversion Project; radial gate; submerged orifice flow AB - 【Objective】The purpose is to examine the applicability and performance of various radial gate flow equations using field data in large scale canal.【Method】Taking Yanlinghe gate of the middle route of South-to-North Water Diversion Project as the object of study, collecting about 18,000 sets of monitoring data, characteristics of submerged orifice flow were analyzed and 7 domestic and international equations were tested.【Result】Froude numbers under gate were between 0.476~3.084, which exceeded the applicable scope of the NHRI empirical equation. The critical e/Hu of orifice flow was near 0.991, which exceeded the applicable scope of WHU empirical equation. The R2 for CAP equation, dimensionless equation, and 3 quadratic empirical equations were 0.989, 0.996, 0.809, 0.822 and 0.832. Corresponding MAE were 2.25%, 2.65%, 4.11%, 4.08% and 3.98%. Errors of all equations were within 10% under low and medium Xr (Xr≤0.9) flow conditions. When Xr was over 0.9, MAE increased significantly, which was 18% (CAP equation), 25% (dimensionless equation) and 35% (3 quadratic empirical equations).【Conclusion】Working conditions examined were beyond the applicable scope of the NHRI empirical equation and WHUEE empirical equation. Errors for Xr≤0.9 were within 10% for all other 5 equations. They increased obviously when Xr was over 0.9. Overall, CAP equation and dimensionless equation showed the best performance. ER -