Open channel for ultrasonic flow measuring device, ultrasonic flow measuring method for open channel, and how to test and modify the open channel for ultrasonic flow measuring device

摘要

PROBLEM TO BE SOLVED: To decrease errors in measuring a flow rate, by correctly measuring a distance between converters and calculating an average horizontal flow velocity. ;SOLUTION: The apparatus is constituted of many horizontal average flow velocity-measuring lines each consisting of a composite converter of a first and a second converters spaced a specific small distance and a third converter separated a specific distance from the composite converter, a switch device having a switching function to impress ultrasonic pulses to the converters, etc., and sequentially receive/output propagated ultrasonic pulses, a square wave formation part for receiving signals from the switch device and shaping a waveform of the signals, a time interval-measuring device for measuring a propagation time interval of pulses from one converter to the other converter among the first, second and third converters, and a synchronous signal generator for generating clock signals of a specific cycle. Moreover, the apparatus includes an operation control device for receiving signals from the time interval- measuring device, calculating a sectional average flow velocity and measuring a flow rate, etc.;COPYRIGHT: (C)1997,JPO