TY - JOUR ID - 72340 TI - Experimental Study of the Effect of Guide Vanes Angle on Discharge Coefficient in Triangular and Trapezoidal Labyrinth Weirs JO - Iranian Journal of Soil and Water Research JA - IJSWR LA - en SN - 2008-479X AU - Agha Shirmohammadi, Ghasem AU - Heidarnejad, Mohammad AU - Pourmohammadi, Mohammad Hossein AU - Masjedi, Alireza AU - Kamanbedast, Amirabbas AD - Department of Water Science Engineering, Khouzestan Science and Research Branch, Islamic Azad University, Ahvaz, Iran AD - Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran AD - Department of Water Science Engineering, Shoushtar Branch, Islamic Azad University, Shoushtar, Iran. AD - Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran. Y1 - 2020 PY - 2020 VL - 51 IS - 1 SP - 191 EP - 199 KW - One-cycle labyrinth weir KW - discharge coefficient KW - Guide vane DO - 10.22059/ijswr.2019.273671.668093 N2 - The discharge coefficient of labyrinth weirs increases with increasing the crest length within a certain width range. This study compares the discharge coefficient in two types of one-cycle triangular and trapezoidal labyrinth weirs. Experiments were conducted on a laboratory flume with length of 6, width of 0.6 and height of 0.6 m. The hydraulic performance of one-cycle triangular and trapezoidal labyrinth weirs with two, four and 6 guide vanes was compared. According to the results, the vanes with a placement angle of 60∘ in the trapezoidal weirs and a placement angle of 45∘ in the triangular weirs on the crests of weirs caused a further increase in the discharge coefficients of weirs. Consequently, at a constant hydraulic head (Hd/P) of 0.2, the discharge coefficient of a trapezoidal weir with two and six guide vanes increased by 38.8 and 10.3%, respectively, as compared to a trapezoidal weir without a guide vane. Furthermore, at a constant hydraulic head (Hd/P) of 0.2, the discharge coefficient of a triangular weir with two and six guide vanes increased 28.3% and 11.7%, respectively, as compared to a triangular weir without a guide vane. UR - https://ijswr.ut.ac.ir/article_72340.html L1 - https://ijswr.ut.ac.ir/article_72340_bb02acf9e292d40d7ada8b5b076b672a.pdf ER -