FREE CONVECTION DUE TO A POINT SOURCE OF HEAT
A point source of heat is considered to be situated in an infinite plane above which the atmosphere was originally isothermal and at rest, and the resulting steady temperature and velocity distribution are sought. As can be observed from the behavior of smoke from a burning cigarette, the flow caused by the heat source is laminar at first, then at some height above it becomes unstable, and the subsequent flow is turbulent. The interdependent distributions of temperature and velocity are obtained in the laminar zone by solving a pair of simultaneous differential equations, and in the turbulent zone by systematic experimentation guided by a dimensional analysis. The transition from laminar to turbulent flow is also investigated. The results are applicable to similar problems of diffusion.