A miniature ultransonic pump using a bending disk transducer and a gap

Area of Science:

• Fluid dynamics
• Acoustic streaming
• Piezoelectric transducers

Background:

• Liquid suction into pipes occurs when a vibrating surface is near the pipe end with a small gap.
• Miniature fluid handling systems are crucial for various applications.

Purpose of the Study:

• To develop and optimize a miniature pump based on acoustic streaming.
• To investigate the effect of pipe geometry on pump performance.

Main Methods:

• Utilized a 30 mm diameter bending disk transducer with a ring-shaped PZT element.
• Operated the disk vibrator at its fundamental resonance frequency of 19 kHz.
• Experimentally optimized the outer diameter of the pipe for maximum pump performance.

Main Results:

• The optimal outer/inner diameter ratio for the pipe was determined to be 3:2 for gaps smaller than 20 micrometers.
• The prototype pump achieved a maximum pressure of 14.8 kPa.
• The prototype pump achieved a maximum flow rate of 10 ml/min.

Conclusions:

• A miniature pump utilizing a bending disk transducer and acoustic streaming is feasible.
• Pipe geometry significantly impacts pump performance, with a 3:2 outer/inner diameter ratio being optimal.
• The developed pump demonstrates potential for microfluidic applications requiring precise fluid delivery.