Experimental Study of a Single Bubble Growth and Detachment from a Submerged Orifice in the Liquid Column Using Passive Acoustic Emission

Authors

Faculty of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran.

Abstract

In the present study, the dynamics associated with single bubble growth and its detachment has been studied using passive acoustic emission and high frame rate imaging methods. Synchronization of imaging with acoustic data acquisition demonstrated the functionality of the acoustic emission method in studying the dynamics of bubble growth and detachment. The investigations showed that the maximum amplitude of the oscillations in the time series of the acoustic emission signal occurs shortly before the bubble detaches. Instantly the rate of bubble volume rise is decelerating. in accordance with the dominant frequency of the acoustic emission wave that arises at the same time with the jump in acoustic time series, the bubble size based on the Minnaert equation with the corrected coefficients is estimated to be only 1.37% different from the results of image processing. According to the sequence of images recorded from the bubble growth frames, the ratio of the vertical and horizontal axis lengths of the bubble is continually changing during the bubble growth period and eventually, the bubble detaches from the orifice when the ratio approaches 1. Although by detachment, the bubble does not have a spherical shape due to the pressure forces.

Keywords


[1]  Terasaka K, Tsuge H (1993) Bubble formation under constant-flow conditions. Chem Eng Sci 48(19): 3417-3422.
[2]  Martín M, Montes FJ, Galán MA (2006) Numerical calculation of shapes and detachment times of bubbles generated from a sieve plate. Chem Eng Sci 61(2): 363-369.
[3]  Duhar G, Colin C (2006) Dynamics of bubble growth and detachment in a viscous shear flow. Phys Fluids 18(7).
[4]  Zhang L, Shoji M (2001) Aperiodic bubble formation from a submerged orifice. Chem Eng Sci 56(18): 5371-5381.
[5]  Vazquez A, Leifer I, Sánchez RM (2010) Consideration of the dynamic forces during bubble growth in a capillary tube. Chem Eng Sci 65(13): 4046-4054.
[6]  Oguz HN, Prosperetti A (1993) Dynamics of Bubble Growth and Detachment from a Needle. J Fluid Mech 257: 111-145.
[7]  Mccann DJ, Princes RGH (1971) Regimes of bubbling at a submerged orifice. Chem Eng 26.
[8]  Minnaert M (1933) On musical air-bubbles and the sound of running water. Philos Mag 16(104): 235-248.
[9]  Plesset MS, Prosperetti A (1977) Bubble Dynamics and Cavitation. Annu Rev Fluid Mech 9(1): 145-185.
[10] Longuet-Higgins M, Kerman B, Lunde K (1991) The release of air bubbles from an underwater nozzle. J Fluid Mech 230: 365-390.
[11] Boyd JWR, Varley J (2001) The uses of passive measurement of acoustic emissions from chemical engineering processes. Chem Eng Sci 56(5): 1749-1767.
[12] Vazquez A, Sanchez RM, Salinas-Rodríguez E, Soria A, Manasseh R (2005) A look at three measurement techniques for bubble size determination. Exp Therm Fluid Sci 30(1): 49-57.
[13] Deane GB, Czerski H (2008) A mechanism stimulating sound production from air bubbles released from a nozzle. J Acoust Soc Am 123(6): EL126-EL132.
[14] Liu J, Wang W, Chu N, Wu D, Xu W (2018) Numerical simulations and experimental validation on passive acoustic emissions during bubble formation. Appl Acoust 130: 34-42.
[15] Huang G, Zhang M, Han L, Ma X, Huang B (2021) Physical investigation of acoustic waves induced by the oscillation and collapse of the single bubble. Ultrason Sonochem 72: 105440.
[16] Dehra H (2019) Acoustic Filters for Sensors and Transducers. Energy Procedia 158(2018): 4023-4030.
[17] Sam A, Gomez CO, Finch JA (1996) Axial velocity profiles of single bubbles in water/frother solutions. Int J Miner Process 47(3-4): 177-196.