Bubbly Two-Phase Flow in Hydraulic Jumps at Large Froude Numbers
نویسنده
چکیده
A hydraulic jump is a sudden, rapid transition from a supercritical flow to a subcritical flow. At large inflow Froude numbers, the jump is characterized by a significant amount of entrained air. For this paper, the bubbly two-phase flow properties of steady and strong hydraulic jumps were investigated experimentally. The results demonstrate that the strong air entrainment rate and the depth-averaged voidfraction data highlight a rapid deaeration of the jump roller. The results suggest that the hydraulic jumps are effective aerators and that the rate of detrainment is comparatively smaller at the largest Froude numbers. DOl: lO.1061/(ASCE)HY.1943-7900.0000323. © 2011 American Society of Civil Engineers. CE Database subject headings: Hydraulic jump; Two phase flow; Froude number; Hydraulic models. Author keywords: Hydraulic jumps; Bubbly two-phase flow; Froude numbers; Physical modeling.
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