Ultrasonic flow meter e.g. clamp-on measuring device, for determining flow rate of fluid in pipe, has ultrasonic transducers determining rate in measuring areas using ultrasonic signals irradiated angular to and against direction of flow

摘要

The flow meter has a first ultrasonic transducer (12) irradiating a first ultrasonic signal (22) angular to and in a direction of fluid flow. A second ultrasonic transducer (16) irradiates a second ultrasonic signal (26) angular to and against the direction of fluid flow. Third and fourth ultrasonic transducers (14, 18) determine flow rate of a fluid in two measuring areas (I, II) using third and fourth ultrasonic signals (24, 28) irradiated angular to and against the direction of fluid flow. The transducers are formed as ultrasonic signal transceivers. An independent claim is also included for a method for determining a flow rate of a fluid in a pipe by Doppler frequency shift.