Ultrasonic system and technique for fluid characterization

A pair of multi-frequency ultrasound transducer surround a fluid flow and are configured to operate under computer control in both a mono-static and a bi-static mode at each of the multiple frequencies. In the mono-static mode, pulsed wideband Doppler shift measurements provide the velocity profile across the fluid flow which can be combined with measured pressure drops to determine the rheogram-a plot of shear stress versus shear rate. Velocity profile data from each frequency can be combined to form a composite velocity profile. In the bi-static mode, transmission data is collected that improves the accuracy and robustness of the velocity profile and provides supplemental material property information. The system is configured for automated operation for a wide variety of fluid types and can be reconfigured and/or monitored remotely.