TWO SAME-SIZED DROPLETS COALESCENCE BY LASER-INDUCED CAVITATION BUBBLES

In this paper, a method for droplets coalescence in microfluidics is proposed using laser-induced cavitation bubbles. A microfluidic chip with T-junction is designed and fabricated to form water droplets in oil continuous phase. An optical laser system with a high speed Charge Coupled Device (CCD) camera is built to generate cavitation bubbles in water droplets and capture the ultra fast process. The cavitation bubbles in water droplets deform and coalesce the water droplets. Two equal size droplets coalescence process are achieved and the growth speed of the radius of the connection neck is investigated.