Periodic solutions of the set of equations governing the nonadiabatic convection of dry isolated thermals
The changes with timet of a temperature deviation δT(t,α) and of a vertical velocityWi(t,α) of an isolated dry thermal have been investigated theoretically. Solutions for the functionWi(t, α) have been derived for stable and unstable environmental stratifications. Comparing these solutions with the corresponding ones for the rise of an adiabatic thermal yield some interesting conclusions.
Firstly, there is the evident relation between the rate of entrainment of environmental air (expressed by the parameter α=(1/Mi) dMi/dz whereMi is the mass of the thermal) and the vertical velocity of the thermal: an increase in α decreases the velocity.
KeywordsAtmosphere Convection Stratification Temperature Deviation Periodic Solution
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