Experimental and theoretical study of various flows along roof flumes

In the closed large areas, when the rain water is collected to transmit it from roof flumes into the underground system, it is important that the collection system is safe in addition to aesthetic considerations.The siphonic rain water drainage systems which are spreadly applied in Turkey, convey quite large discharges to the canalization system by using only a few number of vertical descending pipes.It is necessary to carry out and evaluate experimental studies in order to determine the parameters used in designing of the siphonic rain water drainage system. In such systems, generally the pressurized flow occurs, but from time to time the flow conditions are perturbated because air entertainment. This situation makes the theoretical calculation impossible and some assumptions are required. These assumptions must be based on experimental observations.In this study, it is intended to observe the rain water drainage system for different flow conditions in the experimental system established in the Hydraulic Laboratory within the Civil Engineering Department of Dokuz Eylül University. The pressure measurements are performed on two different pipe layouts and the types of flow are identified. On the other hand, the friction and local head losses are measured, so friction factor and local head loss coefficients are determined experimentally. The measured pressure heads are compared with the theoretical ones calculated by means of the friction factor and local head loss coefficients determined experimentally.