DRAINAGE FUNCTION OF PIPE FLOWS GOVERNED BY FORMATION OF LOCAL FLOW IN MANHOLE

Abstract

Experimental investigation on hydraulics in pipe flows connected to manhole yields that the formation of local flow in manhole is significant for the drainage faculty. The installation of a drop between inlet and outlet pipes connected to manhole and the pressure control in manhole were conducted in the connection with angle of 90, 120, 150, and 180 degrees between inflow and outlet pipes at manhole. Under a wide range of discharges, oulet pipe slopes, and pressure control in manhole, drainage function on pipe flow has been investigated experimentally. The discharge coefficient defined at the upstream end of inlet pipe has been characterized. Also, the discharge coefficient has a maximum 1.2 under the connection angle with 120 degree.