Abstract
Overflow division facilities are most often used in pipeline irrigation systems for paddy fields in Japan. Division structures have been designed and constructed individually because of different values for input discharge, division ratio, and output discharge. A new tower division structure using twin cylindrical pipes has been invented to reduce construction costs. Water flowing into a central pipe underground overflows from the pipe and empties into a doughnut-shaped secondary tank. Discharge is divided with several partitions and flows out through pipes.
Two division devices have been tested with hydraulic experiment to determine whether they can adequately divide discharge. One device allows water to overflow uniformly from around the edge of the central pipe and divides discharge by the length of the arc. The other device allows the water to overflow water from several weirs at the top of the central pipe and divides discharge by the weir widths. Adequate water division will be performed if a suitable combination of input and central pipes is selected and the top end of the centeral pipe is accurately adjusted in a horizontal direction.
