Profile Generator for Ultrasound Doppler Systems

The rheological characterization of the fluids employed in food, pharmaceutical, chemical industries is of paramount importance for product quality and monitoring of the production process. Recently, embedded systems capable of non-invasive and in-line rheological fluid characterization are available. They are based on the Pulsed Ultrasound Velocimetry (PUV) technique, where the velocity profile of the fluid moving in a pipe is detected along the pipe diameter through Doppler ultrasound. The test and accuracy characterization of these systems is currently based on flow-rigs, which consist in hydraulic circuits where pumps push a test fluid along a pipe. Unfortunately, they are cumbersome, and the knowledge of the velocity profile developed in the pipe, to be used as ground-truth in accuracy tests, is limited. In this paper, a flexible testing system for PUV equipment is presented. It generates a radiofrequency signal that mimics the ultrasound Doppler signal produced in a flow-rig. The mimicked velocity profile is programmable and perfectly known. Tests with this generator connected to a PUV system are presented to show its flexibility.