بررسي آزمايشگاهي ضريب دبي و خطوط جريان در سرريز جانبي كليد پيانويي ذوزنقه اي

Experimental Study of Discharge Coefficient and Flow Streamlines in a Trapezoidal Piano Key Side Weir

ﻣﻬﻤﺘﺮﯾﻦ ﮐﺎرﺑﺮد ﺳﺮرﯾﺰﻫﺎي ﺟﺎﻧﺒﯽ، ﮐﻨﺘﺮل و اﻧﺤﺮاف ﺳﯿﻼب و ﻣﺤﺎﻓﻈﺖ ﺳﺎزه ﻣﺮﺑﻮﻃﻪ در ﻣﺨﺎزن ﺳﺪﻫﺎ و رودﺧﺎﻧﻪﻫﺎ اﺳﺖ. اﯾﻦ ﺗﺤﻘﯿﻖ ﻃﯽ ﯾﮏ ﺑﺮرﺳﯽ آزﻣﺎﯾﺸﮕﺎﻫﯽ در ﮐﺎﻧﺎﻟﯽ ﺑﻪ ﻃﻮل 10 ﻣﺘﺮ، ﻋﺮض 0/6 ﻣﺘﺮ، ارﺗﻔﺎع 0/6 ﻣﺘﺮ و 16 ﻣﺪل ﺳﺮرﯾﺰ ذوزﻧﻘﻪاي ﮐﻠﯿﺪ ﭘﯿﺎﻧﻮﯾﯽ ﺗﯿﭗ Aﺑﺎ ﺳﻪﭘﺎﯾﻪ ﻣﺘﻔﺎوت 15 ،10 و 20 ﺳﺎﻧﺘﯽﻣﺘﺮ اﻧﺠﺎمﺷﺪه اﺳﺖ. ﺳﺮرﯾﺰﻫﺎي ﻣﺬﮐﻮر در دو ﺣﺎﻟﺖ ﻗﺮارﮔﯿﺮي در دﯾﻮاره ﮐﺎﻧﺎل اﺻﻠﯽ ﻗﺮارﮔﺮﻓﺘﻪاﻧﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﺑﯿﺸﺘﺮﯾﻦ ﻣﯿﺰان ﺿﺮﯾﺐ دﺑﯽ ﻋﺒﻮري )𝐶𝑀( ﻣﺮﺑﻮط ﺑﻪ ﺳﺮرﯾﺰﻫﺎي ﺑﺎ p= 15 cm در ﻫﺮ دو ﺣﺎﻟﺖ 1 و 2 در ﻧﺴﺒﺖ ﺑﯽﺑﻌﺪ 0/4 < H/P< 0/2 و ﻫﻤﭽﻨﯿﻦ در ﺳﺮرﯾﺰ ﺑﺎ ﻧﺴﺒﺖ ﺑﯽﺑﻌﺪ 0/5 > H/P و p=20 cm ﻣﯽﺑﺎﺷﻨﺪ. درﻧﻬﺎﯾﺖ ﺳﺮرﯾﺰ ﮐﻠﯿﺪ ﭘﯿﺎﻧﻮﯾﯽ ذوزﻧﻘﻪاي ﺑﺎ p= 15 cm و ﺳﺮرﯾﺰ ﺑﺎ B= 50 cm ﻣﻨﺎﺳﺐﺗﺮﯾﻦ رژﯾﻢ ﺟﺮﯾﺎن را از ﺧﻮد ﻋﺒﻮر ﻣﯽدﻫﺪ.

The main application of spillway in rivers and dams reservoirs is control and diversion of flood and protection of their related structures. In this research, a laboratory study was performed to test 16 trapezoid piano key A type weir models with different pillars 10, 15 and 20 cm in a canal with 10 meters length, 0.6 m width and 0.6 m height. The proposed weirs were placed on the main canal wall with two arrangements. The results showed that the maximum overflow rate coefficient was corresponded to weirs with p=15cm in both arranments (1 and 2) and the dimentionless ratio of 0.4 0.2 0.4 and also to weir with dimentionless ratio of 0.5