Level-set simulations of buoyancy-driven motion of single and multiple bubbles

• DOI: 10.1016/j.ijheatfluidflow.2015.07.004
• Publication Date: 2015-07-25T14:16:33Z
• Authors: Néstor Balcázar; Oriol Lehmkuhl; Lluís Jofre; Assensi Oliva
• Keywords: Multiphase flow--Mathematical models; Àrees temàtiques de la UPC::Enginyeria mecànica::Mecànica de fluids; Bubbles--Dynamics; Level-set method; Bubble dynamics; 01 natural sciences; Mètodes de; Level set methods; 0103 physical sciences; Corbes de nivell, Mètodes de; Multiphase flow; Corbes de nivell; Bombolles -- Dinàmica; Flux multifàsic -- Models matemàtics; :Enginyeria mecànica::Mecànica de fluids [Àrees temàtiques de la UPC]

This paper presents a numerical study of buoyancy-driven motion of single and multiple bubbles by means of the conservative level-set method. First, an extensive study of the hydrodynamics of single bubbles rising in a quiescent liquid is performed, including its shape, terminal velocity, drag coefficients and wake patterns. These results are validated against experimental and numerical data well established in the scientific literature. Then, a further study on the interaction of two spherical and ellipsoidal bubbles is performed for different orientation angles. Finally, the interaction of multiple bubbles is explored in a periodic vertical channel. The results show that the conservative level-set approach can be used for accurate modelling of bubble dynamics. Moreover, it is demonstrated that the present method is numerically stable for a wide range of Morton and Reynolds numbers.<br/>Peer Reviewed<br/>