Influence of dispersed particles on thermal rise

Particle-in-cell method is applied to two-dimensional nonstationary problem of heated gas cloud with dispersed particles that rise in atmosphere. As a result space-time distributions of cloud density, pressure and temperature are determined. The results have been compared with the data from the well-known problem of thermal risen due to floatation force. It is demonstrated that if a heated gas cloud has particles, in some cases thermal does not rise but falls following the settling particles. A dependence of the settling speed on particle distribution and diameter is discovered.