Numerical simulations of convection induced by Korteweg stresses in miscible polymer-monomer systems

We modeled a miscible polymer-monomer system with a sharp transition zone separating the two fluids to determine if convection analogous to Marangoni convection in immiscible fluids could occur because of thermal and concentration gradients. We considered three cases: with a temperature gradient along the transition zone, with a variable transition zone width, and one with a gradient in the conversion of polymerization. Using the Navier-Stokes equations with an additional term, the Korteweg stress term arising from non-local interactions in the fluid, we demonstrated with realistic parameters that measurable fluid flow would result in the absence of buoyancy-driven convection for all three cases. To avoid buoyancy-driven convection, the experiment would have to be performed in microgravity.