Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 12, 2016 - November 13, 2016
We experimentally examine the dynamic motion of single bubbles rising in hydrophobically modified alkali-soluble emulsion polymer (HASE) solutions with pH = 7.0. In this study, 1.80wt%TT935, 0.551wt% TT615 and 0.550wt%TT615 HASE solutions are used and we focus on the velocity jump discontinuity of the rise velocity. From experimental observations, we confirm that the velocity jump occurs for all the HASE solutions as a critical bubble volume is exceeded. We present that bubbles rising in TT615 HASE solutions may exhibit the velocity jump twice. It is found that the large-scale velocity jump for all the HASE solutions is closely related to the bubble shape: the velocity jump occurs when a threadlike long tail is formed at the rear of the bubble.
