Investigation of convective structures near the stability threshold in non-Boussinesq fluid. Part one—analysis of simple models

The paper investigates stable convective structures in vertically asymmetric horizontal fluid layer. The asymmetry is caused by internal heat generation, variable thermal diffusion and variable kinematic viscosity (temperature and vertical coordinate dependence is considered). The first part of the paper provides analysis of Prandtl number effect on the planform selection in scope of amplitude equations and perturbation method. The second part of the paper deals with a comparison of theoretical data to results of 3D numerical simulation of convective instability in finite layer of non-Boussinesq fluid.