Item Infomation

Title: A Compound Droplet Undergoing Thermocapillary Migration Passing Through a Constricted Tube
Authors: Vinh, Nguyen
Truong, Van
Phan, Nguyen
Hoe, Nguyen
Binh, Pham
Hung, Vu
Issue Date: 2022
Publisher: The American Society of Mechanical Engineers
Abstract: In this paper, we numerically investigate the dynamics of a compound droplet driven by surface tension variation induced by a thermal gradient in a sinusoidal constriction tube. Initially, the compound droplet with a concentric inner core is spherical and placed in the constriction's upstream region with a low temperature. As time progresses, it migrates to the downstream with a high temperature. Due to the constriction, the droplet is slowed down in the upstream region and accelerated again right after passing the constriction. This acceleration maximizes the eccentricity. However, the constriction results in an increase in the maximum eccentricity when increasing its depth to a value corresponding to the size of the tube neck, which is greater than or equal to the droplet size. Effects of various parameters, e.g., the Marangoni number Ma, the capillary number Ca and the radius ratio Rio, are studied. It is found out that increasing the Ma number or decreasing the Ca number reduces the maximum eccentricity and prolongs the travel time, i.e., the arrival time, from the upstream to the downstream. Similar reduction in the maximum eccentricity also occurs with the increased Rio ratio. Effects of these parameters on the migration velocity are also revealed
Appears in CollectionsBài báo khoa học




Files in This Item:
There are no files associated with this item.