Evolution of liquid and gas phases in multi‐plume spray injection. (16th June 2016)

• Record Type: Journal Article
• Authors: Ghasemi, Abbas; Pereira, Aaron; Li, Xianguo
• Is Part Of: International journal of energy research. Volume 40:Number 14(2016)
• Page Start: 1935
• Page End: 1950
• Publication Date: 2016-06-16
• Subjects: spray characterization -- large eddy simulation -- jet -- vorticity -- two‐phase interaction; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Power resources -- Research -- Periodicals; 621.042
• DOI: 10.1002/er.3562
• Languages: English
• ISSNs: 0363-907X

Abstract

Summary: In this study, the unsteady development of multi‐plume sprays has been investigated by large eddy simulations with Eulerian–Lagrangian multiphase approach for both global spray characteristics and local flow features. Multi‐plume sprays are injected at the injection pressures of 10 MPa and 15 MPa, and the temperature of T s = 297.65 K into the ambient air at the atmospheric pressure and temperature of T a = 293.15 K. Experimentally obtained global multi‐plume spray characteristics in terms of spray shape and penetration are used to validate the present numerical simulations. The present numerical predictions for Sauter mean diameter and its temporal variation agree well with the empirical correlations. The predicted droplet size distribution evolves temporally and spatially, and exhibits bimodal distribution, until eventually the mode for small droplet sizes dominates. The spray plumes are found to have limited interaction due to the relatively large orientation angles between the plumes. Because of the momentum transfer from the liquid to gas phase, spray‐induced air jets appear in the multi‐plume sprays. Using vorticity, pressure, and λ 2 − criterion fields, it is shown that the spray‐induced air jets form similar vortical structures as single phase jets. Similarities between the spray‐induced air jets and single phase jets in terms of the shear layer vortical structures such as hairpin‐like vortices improves our understanding of the entrainment and mixing processes in multi‐plume sprays. Copyright © 2016 John Wiley & Sons, Ltd. Abstract : Unsteady development of multi‐plume sprays is investigated by large eddy simulations and experiments for their spatiotemporal evolution of both the liquid and gas phases; the global flow characteristics are compared and agree with the experimental results; while the local flow features are analyzed for the evolution and distribution of the drop sizes, and the spray‐induced air jets in the multi‐plume sprays characterized by using vorticity, pressure, and fields.