CFD Simulation of Polydispersed Bubbly Two-Phase Flow around an Obstacle

Autor: E. Krepper, P. Ruyer, M. Beyer, D. Lucas, H.-M. Prasser, N. Seiler
Jazyk: angličtina
Rok vydání: 2009
Předmět:
Zdroj: Science and Technology of Nuclear Installations, Vol 2009 (2009)
Druh dokumentu: article
ISSN: 1687-6075
1687-6083
DOI: 10.1155/2009/320738
Popis: This paper concerns the model of a polydispersed bubble population in the frame of an ensemble averaged two-phase flow formulation. The ability of the moment density approach to represent bubble population size distribution within a multi-dimensional CFD code based on the two-fluid model is studied. Two different methods describing the polydispersion are presented: (i) a moment density method, developed at IRSN, to model the bubble size distribution function and (ii) a population balance method considering several different velocity fields of the gaseous phase. The first method is implemented in the Neptune_CFD code, whereas the second method is implemented in the CFD code ANSYS/CFX. Both methods consider coalescence and breakup phenomena and momentum interphase transfers related to drag and lift forces. Air-water bubbly flows in a vertical pipe with obstacle of the TOPFLOW experiments series performed at FZD are then used as simulations test cases. The numerical results, obtained with Neptune_CFD and with ANSYS/CFX, allow attesting the validity of the approaches. Perspectives concerning the improvement of the models, their validation, as well as the extension of their applicability range are discussed.
Databáze: Directory of Open Access Journals