دﺑﯽ ﻋﺒﻮري ﺳﺮرﯾﺰ ﺟﺎﻧﺒﯽ در ﮐﺎﻧﺎل ﻫﺎي داﯾﺮه اي

Discharge Capicity of side Weirs in circular channels

ﺳﺮرﯾﺰﻫﺎي ﺟﺎﻧﺒﯽ ﯾﮑﯽ از ﻣﻬﻢ ﺗﺮﯾﻦ ﺳﺎزهﻫﺎي ﺣﻔﺎﻇﺘﯽ در ﺑﺎﻻدﺳﺖ ﺳﺎزهﻫﺎي ﻧﻈﯿﺮ ﺳﯿﻔﻮن ﻣﻌﮑﻮس و زﯾﺮﮔﺬر ﺟﺎدهﻫﺎ در ﺷﺒﮑﻪﻫﺎي آﺑﯿﺎري و زﻫﮑﺸﯽ ﻫﺴﺘﻨﺪ. در اﯾﻦ ﺗﺤﻘﯿﻖ ﺑﺎ اﺳﺘﻔﺎده از دادهﻫﺎي آزﻣﺎﯾﺸﮕﺎﻫﯽ و ﺣﻞ ﻋﺪدي در ﺣﺎﻟﺖ ﺟﺮﯾﺎن ﺑﻪ ﺻﻮرت آزاد در ﻟﻮﻟﻪ رواﺑﻂ ﺟﺪﯾـﺪي ﺑـﺮ اﺳـﺎس ﻋﻤـﻖ ﺑﺤﺮاﻧـﯽ ﺟﺮﯾﺎن ﺑﺎﻻدﺳﺖ ﺑﺮاي ﺗﻌﯿﯿﻦ ﻇﺮﻓﯿﺖ ﺗﺨﻠﯿﻪ ﺳﺮرﯾﺰﻫﺎي ﺟﺎﻧﺒﯽ در ﮐﺎﻧﺎلﻫﺎي داﯾﺮهاي )ﻟﻮﻟﻪ( در ﺣﺎﻻت ﺑﺤﺮاﻧﯽ و ﻓﻮق ﺑﺤﺮاﻧﯽ اراﺋﻪ ﺷﺪه اﺳﺖ. اﯾﻦ راﺑﻄﻪ ﺑﻪ ﭘﺎراﻣﺘﺮﻫﺎي ﻣﺆﺛﺮ از ﻗﺒﯿﻞ P/y1، ارﺗﻔﺎع ﺗﺎج ﺳﺮرﯾﺰ ﺑﻪ ﻋﻤﻖ ﺟﺮﯾﺎن در اﺑﺘﺪاي ﺳﺮرﯾﺰ، ارﺗﻔﺎع ﺟﺮﯾﺎن روي ﺗﺎج ﺳﺮرﯾﺰ ﺑﻪ ارﺗﻔـﺎع ﺳـﺮرﯾﺰ )(y1-p)/p( و ﻋﻤـﻖ ﺑﺤﺮاﻧﯽ ﺟﺮﯾﺎن ﮔﺬرﻧﺪه روي ﺗﺎج ﺳﺮرﯾﺰ ﺑﺴﺘﮕﯽ دارد. ﻧﺘﺎﯾﺞ اﯾﻦ ﭘﮋوﻫﺶ ﻧﺸﺎن داد، ﻣﻘﺪار دﺑﯽ ﻋﺒﻮري ﺟﺮﯾﺎن در ﺑﺎﻻدﺳﺖ در ﺣﺎﻟﺖ ﺟﺮﯾﺎن زﯾﺮﺑﺤﺮاﻧﯽ ﺑﯿﺸﺘﺮ از ﺣﺎﻟﺖ ﺟﺮﯾﺎن ﻓﻮق ﺑﺤﺮاﻧﯽ اﺳﺖ. ﻫﻤﭽﻨﯿﻦ رواﺑﻂ اراﺋﻪ ﺷﺪه ﺟﻬﺖ ﻣﺤﺎﺳﺒﻪ دﺑﯽ ﻋﺒﻮري ﺳﺮرﯾﺰﻫﺎي ﺟﺎﻧﺒﯽ در ﮐﺎﻧـﺎل ﻫـﺎي داﯾـﺮه اي ﺑـﻪ ﻋﻠـﺖ دارا ﺑـﻮدنرﮔﺮﺳﯿﻮن ﺑﺎﻻ و ﻫﻤﺨﻮاﻧﯽ ﻧﺘﺎﯾﺞ ﻣﺤﺎﺳﺒﺎﺗﯽ و ﻣﺸﺎﻫﺪاﺗﯽ ﺟﻬﺖ ﻃﺮاﺣﯽ اﯾﻦ ﻧﻮع ﺳﺮرﯾﺰﻫﺎي ﺟﺎﻧﺒﯽ در ﮐﺎﻧﺎلﻫﺎي داﯾﺮهاي ﭘﯿﺸﻨﻬﺎد ﻣﯽﺷﻮد.

Side weirs are one of the most important protective structures upstream of structures such as reverse siphons and underpasses in irrigation and drainage networks. In this research, using laboratory data and numerical solution in free flow mode in the pipe, new relationships based on the critical depth of the upstream flow to determine the discharge capacity of sideweirs in circular channels (pipes) in critical situations and Supercritical is presented. This relationship depends on effective parameters such as P / y1, weir crown height to the depth of flow at the beginning of the weir, flow height over the weir crown to weir height ((y1-p) / p) and critical depth of the flow passing over the weir crown. The results of this study showed that the upstream flow rate in the subcritical flow mode is higher than the supercritical flow mode. Also, the relations provided for calculating the flow rate of side weirs in circular channels are suggested due to having high regression and consistency of computational and observational results for designing this type of side weirs in circular channels