Transverse flow velocity measurement using a single circular planar transducer by ultrasonic Doppler-spectra

A method to measure the transverse velocity of particle flow passing across the ultrasonic beam is discussed. We run the numerical simulations of the ultrasonic wave scattered by particle(s) and received at the transducer when particle(s) flow perpendicular to the axis of the circular planer transducer which creates an ultrasonic beam. It is observed that the spectrum bandwidth of the signal agrees to the Doppler shift occurring due to components of the velocity of the moving particle, especially when the beam diverges. Thus, the bandwidth varies depending on the velocity. The simulation also shows that the spectrum bandwidth is consistent when multiple particles are continuously flowing along a line passing across the ultrasonic beam in a constant velocity with the case of a single particle. The simulation is partly validated by an experimental result in a literature. This study implies the feasibility of the method for the transverse velocity measurement of a continuous particle flow and practical approaches for the implementation of the method.