Understanding and control of coalescence of droplets with suspended particles in flow through a tube

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05809
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: Tokyo University of Science
• Principal Investigator: Muraoka Masahiro 東京理科大学, 理工学部機械工学科, 講師 (70219880)
• Co-Investigator(Kenkyū-buntansha): 溝口 博 東京理科大学, 理工学部機械工学科, 教授 (00262113) ; 上野 一郎 東京理科大学, 理工学部機械工学科, 教授 (40318209)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 液滴 / 粒子 / 合体運動 / 円管内の遅い流れ

Outline of Final Research Achievements

Coalescence of droplets with suspended particles in creeping flow through a tube were examined. Three types of the gold-coated acrylic particles were employed, 5μｍ, 15aμｍ and 30μｍ in diameter, respectively. Volume concentration of particles ranged from 0.08% to 0.4 %. Reynolds number of the tube flow ranged from 0.01 to 0.08. Coalescence time of droplets was measured and compared with the predictions of semi-theoretical formulas. Coalescence time with particle in all cases of particle size was obviously shorter than that without particle. The experimentally measured coalescence times with particle agreed roughly with the values predicted by semi-theoretical formulas for the case of Re=0.01. The values predicted by semi-theoretical formulas deviate from the experimentally measured coalescence times with increasing Re. It is considered that the effect of the rotation of the following droplet is not taken into account in the semi-theoretical formulas.

Free Research Field

流体力学