Convection of Strong Stratified Colloidal Suspension

The сonvective instability and nonlinear flows of a colloidal suspension in horizontal layer are studied in the case when the layer height is comparable with the sedimentation length of nanoparticles. The numerical analysis is carried out within the Boussinesq approximation on the basis of a modified model that takes into account the dependence of a thermal diffusion flux on the local value of impurity concentration. The stability borders and characteristics of critical disturbances are determined depending on the sedimentation length for colloidal mixture. The bifurcation phenomena and nonlinear evolution of spatiotemporal patterns that develop in the colloid suspension are modeled and discussed, paying special attention to the combined effects of gravity sedimentation, thermal diffusion with negative separation ratio and convection. The nonlinear convection patterns demonstrate the traveling wave dynamics. It is found the new traveling wave solution, which is characterized by an anharmonic distribution of the vertical velocity through the layer.