Interfacial Instabilities of a Miscible Droplet in a Hele-Shaw Cell

• Main Author: 王蜀偉
• Other Authors: CHEN, C.-Y.
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/96523331737679747669

碩士 === 大葉大學 === 機械工程研究所 === 90 === Numerical simulations of fingering stabilities in a miscible rotating Hele-Shaw flow in both the prewetted and dry situations by means of high accurate numerical schemes are presented. The interfacial instability is dominated by three control parameters, such as rotating speed, viscosity contrast, and diffusion between the species. Unstable mechanism is resulted from the centrifugal force if the heavier annulus, in general more viscous that provides stable viscous damping effect. The effect of stronger diffusion is not significant to the fingering patterns, but leads only to milder instability. The interfacial stability appears more complex for a more viscous miscible annulus, or the injection of less viscous fluid. The outer interface is rotational unstable and viscous stable. However, the inner front performs differently. The injecting strength tends to stabilize the outer interface, and perturbs the inner. In general, inertial reference condition leads to more significant instabilities associated with multi-layer front, which is similar to the emission of liquid droplets found in immiscible experimental results (Carrillo et al 2000).