DYNAMICS OF DROPS AND BUBBLES IN NEWTONIAN AND VISCOELASTIC FLOWS
Document Type
Conference Proceeding
Publication Date
1-1-1999
Abstract
A finite element code based on the level set method is developed for simulating the motion viscoelastic free-surfaces in two-dimensions. This method is a generalization of the one described in Osher and Sethian (1988) where the free-surface problems of inviscid and viscous fluids were simulated. The code is used to study deformation of drops in simple shear and Poisuelle flows over a wide range of dimensionless capillary (Ca) and Deborah numbers (De). Simulations show that there are limiting values of these two parameters below which the drops assume steady state shapes. For values greater than these limiting values, on the other hand, there is no steady state shape and the drop continued to deform. For a Newtonian bubble rising in a quiescent viscoelastic liquid we again find that there are limiting values of the parameters De and Ca, above which the bubble assumes a characteristic shape with a cusp-like trailing edge. The numerical results show that the viscoelastic stresses near the trailing edge are extensional and act in the direction normal to the drop surface. The front of the bubble however remains round as the local viscoelastic and viscous stresses act to round the bubble. These results are in good agreement with the experimental results.
Identifier
85122681867 (Scopus)
ISBN
[9780791816615]
Publication Title
ASME International Mechanical Engineering Congress and Exposition Proceedings Imece
External Full Text Location
https://doi.org/10.1115/imece1999-1227
First Page
169
Last Page
174
Volume
1999-N
Grant
NSF/CTS-98-73236
Fund Ref
National Science Foundation
Recommended Citation
Pillapakkam, Shriram B., "DYNAMICS OF DROPS AND BUBBLES IN NEWTONIAN AND VISCOELASTIC FLOWS" (1999). Faculty Publications. 16052.
https://digitalcommons.njit.edu/fac_pubs/16052
