Influence of the vibrating system of a multipinhole-plate ultrasonic nebulizer on its performance

Abstract

A multipinhole-plate ultrasonic atomizer was experimentally optimized, employing a bender bimorph vibrator structure made up of a thin pinhole plate and a circular ring piezoelectric element. Effects of the vibration mode upon the performance were studied in terms of the sound pressure generation and the behavior of bubbles caused by cavitation. The performance was also examined with regard to the number of pinholes and the shape of the pinhole plate. As a result, the atomizer was proved to be able to jet and nebulize ordinary liquid most efficiently by the second harmonic vibration mode if the vibrating system is supported along the circumference of the ring piezoelectric element. It was also proved that the maximum atomizing rate is approximately proportional to the number of pinholes and that the spray pattern can easily be controlled by changing the shape of the pinhole plate.