Performances of Vertical Diffusers for Air-water Mixture Flow

抄録

Diffuser performances for the two-phase flow of air-water mixture have been scarcely studied, though those for the mono-phase flow have been examined and the optimum diffuser profile is given. The diffuser performance for the mixture flow may be affected not only by the channel profile but also by the inlet velocity of the diffuser. Thus, this study aims to make clear the efficiencies of vertical diffuser with rectangular cross-section and to obtain the desirable channel profile and the inlet velocity, for the air-water mixture flow. The efficiency deteriorates as the air-water mixture ratio increases, and the desirable inlet velocity exists for each mixture ratio and channel profile. The highest efficiency is obtained when the diffuser length-width ratio l/W is about 7 irrespective of the mixture ratio. At l/W ≒7, the optimum divergent angle and inlet velocity are also determined from this result.