کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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156449 | 456932 | 2011 | 18 صفحه PDF | دانلود رایگان |
A lattice Boltzmann equation (LBE) model based on the Cahn–Hilliard diffuse interface approach is used to investigate the dynamics of a bubble rising in a vertical and inclined square channel with large density and viscosity ratios. Deformation parameter ΔΔ, film thickness δδ, and terminal velocity Ut of the bubble are interrelated quantities which depend on non-dimensional numbers such as Bond number Bo, Morton number Mo, and ratio between bubble diameter and channel width k as it was reported by previous experimental studies. As k is increased, higher ΔΔ and smaller δδ are exhibited. This finding is independent of the value of Bo and Mo . In addition, a relationship was established between δδ and ΔΔ with non-dimensional numbers such as Capillary number Ca and Weber number We. An evaluation was performed for inclined channels to relate the Froude number Fr with the inclination angle θθ, where in each case there is a critical value of θθ which corresponds to the highest value of Fr, consequently highest Ut. This finding is consistent with previous simulation and experimental results. Moreover, a relation was established between the critical value of θθ and Ca and Bo. This three-dimensional study was performed using a range of Bo (1
Journal: Chemical Engineering Science - Volume 66, Issue 5, 1 March 2011, Pages 935–952