S055014 マイクロバブルを含むミルキーバブルの鉛直管内流による摩擦抵抗低減効果([S05501]流れの抵抗低減(1))

概要

論文の詳細を見る
In recent years micro bubbles are used in the field of agriculture, industry and so on. But drag reduction effect with micro bubbles and its mechanism are not confirmed sufficiently. Thus, in the present study, the drag reduction effect of micro bubble in the turbulent flow, which is called milky bubble flow in this paper, was performed. The measurements were carried out under the conditions of the pipe diameter 16.0 mm, the entrance length 520mm, test section length 2000mm, and 1.5 x 104< Re < 3.0x 104, where Re is the Reynolds number. A pressurized dissolution method was employed to make micro bubbles. The frictional pressure loss was measured with two manometers. That of milky bubble flow was measured with changing the void fraction aG, liquid velocity and Re. The effect of the surface acting agent (3-pentanol) was also investigated. As the result, we confirmed that (1) drag reduction effect of 6.6 % at most in the milky bubble flow, (2) drag reduction effect of 8.8% at most when mixing the surface acting agent in milky bubble flow.
一般社団法人日本機械学会の論文
2011-09-11