FLOW RATE MEASURING METHOD AND FLOW RATE MEASURING DEVICE IN BURIED T-SHAPED OR CRUCIFORM WATER SUPPLY PIPELINE

摘要

PROBLEM TO BE SOLVED: To easily measure the flow rate and the direction of the flow of water which flows in each of the branch pipes of a buried T-shaped or cruciform water supply pipeline.;SOLUTION: A hydraulic pressure sensor is attached to a fire hydrant or a slurry-discharging pipe which has been mounted on each of the branch pipes and which can be accessed from the ground, and water pressure in the pipe is measured. Then the survey of the height of the hydraulic pressure sensor at each of the hydraulic-pressure measurement points and the pipeline length from a joint which is the point of intersection of each of the branch pipes to each of the measurement points is performed. Each of the measured data and the survey data are substituted into a Hasen Williams formula, and an equation is formulated which is used for calculating the flow rate flowing toward the joint in each of the branch pipes. The Hasen Williams formula is used for calculating the flow rate in the pipeline from a friction head, a pipe diameter, a pipeline length, and a flow velocity coefficient. Then the moving head of the joint is assumed, and the moving head of the joint is determined which controls the absolute value of the sum of the flow rate flowing toward the joint in each of the branch pipes to a microallowable flow rate while adding a correction to the assumed value. The flow rate at that time is made the flow rate which each of the branch pipes determine.;COPYRIGHT: (C)2009,JPO&INPIT