FORMULA ON ENERGY LOSSES AT FOUR-WAY CIRCULAR MANHOLE UNDER SURCHARGE FLOW

Energy loss in a manhole as junction of storm sewers or combined is an important factor for more accurate calculation inundation. The authors formulated energy coefficients two-way and three-way circular drop manholes where one two inflow pipes are connected to outflow pipe. Since there few studies on the four-way three pipe like at intersection, we conducted experiments which with several types inner diameter flow rate. We successfully obtained characteristics through experiments. Furthermore, developed formulas manhole, considering structural elements hydraulic factors manhole. results calculated formulae were fair agreement measured values.