Numerical simulation of annular flow hydrodynamics in microchannels

• Published in: Computers & fluids Vol. 133; pp. 90 - 102
• Main Authors: Guo, Zhenyi, Fletcher, David F., Haynes, Brian S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.07.2016
• Subjects: Annular flow; Annular flow hydrodynamics; Boiling; Computational fluid dynamics; Computational fluid dynamics (CFD); Computer simulation; Flow boiling in microchannels; Fluid flow; Hydrodynamics; Interfacial instabilities; K-H instability; Mathematical models; Microchannel annular flow; Microchannels; Interfacial instabilities; Annular flow hydrodynamics; Microchannel annular flow; K-H instability; Computational fluid dynamics (CFD); Flow boiling in microchannels
• ISSN: 0045-7930; 1879-0747
• DOI: 10.1016/j.compfluid.2016.04.017

•CFD simulation of steady, laminar, fully-developed annular flow.•Investigation of Kelvin-Helmholtz instability using numerical perturbations.•Numerical investigation of interfacial instabilities of inviscid parallel flows.•Comparison between simulation results and existing analytical theories. Annular flow is the dominant flow regime in microchannel flow boiling because it appears at very low vapor quality and persists until dryout at high quality. This flow regime is hydrodynamically unstable, as the phase interfaces are subject to instabilities triggered by flow perturbations. In this work, a computational fluid dynamics (CFD) model is proposed and verified for the studies of annular flow hydrodynamics in microchannels, using the commercial software ANSYS Fluent. Verification of the model is performed by comparing simulation results with existing analytical theories. The potential for the application of this model to microchannel annular flow boiling has been demonstrated.