Abstract: A method is provided for measuring the flow rate of a fluid in a pipe using at least two ultrasonic transducers. The method includes a succession of cycles (35) of transmissions, each comprising a sub-cycle A in which an ultrasonic wave is transmitted by a first transducer and a sub-cycle B in which an ultrasonic wave is transmitted by a second transducer. The propagation times of these two waves are measured, wherein the order between the sub-cycle A and the sub-cycle B is reversed between the successive transmission cycles, and a flow rate is calculated from an average of: a difference between the two measured propagation times of a given transmission cycle, and a difference between the two measured propagation times of a second transmission cycle following the given transmission cycle.

Abstract: The invention relates to a flow measurement method comprising a generation of successive cycles, each cycle comprising: —a step (35) in which an ultrasonic wave is emitted by a first ultrasonic transducer; —a step (36) in which said ultrasonic wave is received by a second ultrasonic transducer; and —a step (37) in which a propagation time of said ultrasonic wave from the first ultrasonic transducer to the second ultrasonic transducer is measured, the method being characterised in that a given cycle is separated from the preceding cycle by an intercycle duration, and in that a flow rate of the fluid is calculated from a difference between the propagation time of the given cycle and an average of the propagation time measured for the preceding cycle and that measured for the cycle following said given cycle.