A Numerical Experiment in Buoyant Convection Involving the Use of a Heat Source

View More View Less
  • 1 University of California, Los Angeles
© Get Permissions Rent on DeepDyve
Restricted access

Abstract

The effect of a constant source of heat on the development of a buoyant element is investigated by means of the numerical integration of a set of hydrodynamical equations. The heat source is inserted at the initial base of a buoyant element, and the surrounding fluid is initially neturally stratified and at rest.

Two-dimensional, non-divergent motion is considered in a vertical plane 760 meters wide and 600 meters deep. The buoyant element, whose maximum potential temperature exceeds that of the environment by 0.5C, is located 100 meters above the lower boundary. Finite difference analogs of the governing equations are integrated numerically on an IBM 7094 to obtain 10-minute forecasts for the potential temperature and stream function fields.

During the early few minutes of the experiment before the thermal begins its ascent, a vortex circulation develops and the temperature within the thermal increases due to the heating. As the bubble rises above the heat source, the maximum temperature within the bubble reaches a peak and then decreases when the effects of eddy dissipation exceed the increase in buoyancy. The warm stern connecting the bubble with the heat sources becomes progressively narrower, until at 10 minutes the configuration of the potential temperature field resembles a thin-stemmed mushroom.

Abstract

The effect of a constant source of heat on the development of a buoyant element is investigated by means of the numerical integration of a set of hydrodynamical equations. The heat source is inserted at the initial base of a buoyant element, and the surrounding fluid is initially neturally stratified and at rest.

Two-dimensional, non-divergent motion is considered in a vertical plane 760 meters wide and 600 meters deep. The buoyant element, whose maximum potential temperature exceeds that of the environment by 0.5C, is located 100 meters above the lower boundary. Finite difference analogs of the governing equations are integrated numerically on an IBM 7094 to obtain 10-minute forecasts for the potential temperature and stream function fields.

During the early few minutes of the experiment before the thermal begins its ascent, a vortex circulation develops and the temperature within the thermal increases due to the heating. As the bubble rises above the heat source, the maximum temperature within the bubble reaches a peak and then decreases when the effects of eddy dissipation exceed the increase in buoyancy. The warm stern connecting the bubble with the heat sources becomes progressively narrower, until at 10 minutes the configuration of the potential temperature field resembles a thin-stemmed mushroom.

Save