Fig. 3

Sketch of the different configurations to measure pressures. a Calibration setup, where the tube is connected to the calibration port I2 (see Fig. 1). b Pressure drop measurement using the Kistler probe 7261 using a 3-way stopcock open to the atmosphere. c Assembly to measure the pressure of the air-pulses and the effect of the distance and impact angle. d Assembly similar to that used by Aviv and Hammer to measure the air-pulses [29, 31, 34]. e Assembly to measure the impact force (pressure) using a precision balance. In this last case, the balance plate is horizontal, and the air-pulses arrive from the top. f Picture of the Kistler sensor, where the cover and the transducer can be distinguished. g Sensor MPX2010D, where the air-pulse impacts the cavity hole that is placed in face of the distal end in the Aviv and Hammer studies configuration (d)