Acoustically driven turbulence amplifier for pneumatic valves control

The design of a bistable electro-pneumatic interface based on laminar-to-turbulent jet transition is herein presented. This principle, used in the past to produce air stream controlled fluidic turbulence amplifiers, is now applied to a new interface driven by acoustic waves and controlled through very low power electrical signals. The study was performed experimentally, attempting to find the optimum interface geometry and analysing its sensitivity to acoustic signals in a frequency range from 2 to 20 kHz and at different excitation levels. A piezo-electric buzzer was used as sound source, resulting in a device with electric power consumption of less than 5 mW, able to switch common low/high pressure pneumatic valves.