Pressure probe with five embedded flush-mounted sensors: unsteady pressure and velocity measurements in hydraulic turbine model

摘要

The unsteady five-hole Pitot tube, with embedded flush-mounted sensors, provides one of the most advanced experimental techniques in fluid mechanics stemming from Pitot tube. This instrument enables the measurement of both unsteady pressures and instantaneous three-dimensional velocity vectors. The present paper focuses on the methodology and use of this type of probe in hydraulic turbines. Different fluctuating phenomena can be monitored, providing reliable estimates regarding amplitude and frequency. The probe is particularly advantageous for applications when the flow exhibits large angular fluctuation. In such cases, even the mean values must be validated using unsteady measurements. The calibration method and the validation of the unsteady measurements are presented through three different hydraulic turbine models.