TY - JOUR
TI - A hydrodynamic criterion of alternative bubble departures
AU - Dzienis Paweł
AU - Mosdorf Romuald
AU - Tomaszuk Daniel
AU - Wyszkowski Tomasz
JN - Thermal Science
PY - 2021
VL - 25
IS - 1
SP - 553
EP - 565
PT - Article
AB - The bubble departures from two neighboring brass nozzles (with inner diameter of 1.1 mm) in three liquids: distilled water, mineral, and synthetic engine oils were investigated. The numerical simulations were used for reconstruction of liquid-flow around the departing bubbles. Bubble movements in liquid have been recorded using a high speed camera. The 2-D bubble paths have been reconstructed using: Laplacian of Gaussian filters, algorithm of detection of local extremes of image brightness and Kalman filter. It was shown that during alternative bubble departures bubble paths become repeatable. The dimensionless number (similar to Strouhal number) was proposed to describe oscillating liquid-flow generated by departing bubbles over the nozzle outlet. Such number was used for defining the hydrodynamic criterion of alternative bubble departures