Resonant bubbles in a vertically vibrating liquid column

This paper reports measurements and theory concerning stationary, resonant single bubbles which have been formed in a vertically vibrating liquid column at frequencies of 40–1050 c./s. With liquids of high viscosity (ca. 10 poise) the bubbles can be made large enough to occupy the entire cross‐section of the 2 1/2 in. diameter column: intense agitation is produced in the liquid above the large bubble or slug. Theoretical equations are derived for the resonant frequency of the stationary bubbles: agreement with measured frequency is within 20% for bubbles which only partly fill the column cross‐section and within 10% for bubbles occupying the entire cross‐section. Viscous damping appears to be important in the latter case.