Numerical simulations of transient interfacial phenomena in miscible fluids AIAA-2004-631
We continue our numerical investigation of the transient interfacial phenomena in miscible fluids as part of the Transient Interfacial Phenomena in Miscible Polymer Systems (TIPMPS) flight investigation. We use a model consisting of the heat and diffusion equations with convective terms and of the Navier-Stokes equations with an additional volume force written in the form of the Korteweg stresses arising from nonlocal interaction in the fluid. It is proportional to the square of the composition gradient with the proportionality coefficient depending on temperature. We estimate this square gradient parameter on the basis of measurements from spinning drop tensiometry on poly(dodecyl acrylate)/dodecyl acrylate and the Flory-Huggins theory of polymer-solvent interactions. We carried out numerical simulations of this model and show that the capillary force can cause convection in the initially quiescent liquid. For physically realistic values of parameters the liquid motion, though decreasing rapidly in time, can be observed experimentally. We include in the model viscosity that depends on temperature and concentration. We also include mass diffusion coefficients that depend on temperature. We also show that convection caused by the change in volume during polymerization to create the initial conditions is much less than predicted from the Koreteweg effect. We also explore more realistic initial and boundary conditions. We simulate three scenarios: A temperature gradient parallel to the polymer/monomer transition zone A variation in the width of the polymer/monomer transition zone A variation in the polymer conversion along the polymer/monomer transition zone.
Publication Source (Journal or Book title)
Bessonov, N., Pojman, J., & Volpert, V. (2004). Numerical simulations of transient interfacial phenomena in miscible fluids AIAA-2004-631. AIAA Paper, 6126-6133. Retrieved from https://digitalcommons.lsu.edu/chemistry_pubs/1196