| 摘要 |
PROBLEM TO BE SOLVED: To provide a flowmeter by which a flow rate can be found with good accuracy without using a correction factor and to provide a flow-rate measuring method. SOLUTION: A flow velocity sensor 320 and a flow velocity sensor 321 are arranged in a projection cross section inside a pipe line so as to transmit ultrasonic waves toward the central point. The width of the pipe line is standardized so as to reach 1 from -1 in its up-and-down direction, and coordinates are set in the up-and-down direction. In a plurality of depths of water (z=z0, z1) which become roots (z1,...zn) of the Legendre spherical function Pn(z) with reference to the Pn(z), the width of the pipe line in the respective depths of water is standardized so as to reach 1 from -1 in the horizontal direction, and the coordinates are set in the horizontal direction. Flow velocities are measured in a plurality of points P00, P01, P10, P11 as roots (x1,...xn) of the Legendre spherical function Pn(x) with referenced to the PN(x). On the basis of the width of the pipe line in the horizontal direction in the respective depths of water and on the basis of the flow velocities in the measuring points, the Gaussion numerical value is integrated, the area of the distribution of the flow velocities in the respective depths of water is calculated, the area of the distribution of the flow velocities on the respective depths of water is integrated, and the flow rate of the pipe line as a whole is calculated. |
