Accession Number : AD0717670

Title :   A Numerical Model of a Convective Cell Driven by Non-Uniform Horizontal Heating.

Descriptive Note : Master's thesis,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF METEOROLOGY

Personal Author(s) : Festa,John F.

Report Date : NOV 1970

Pagination or Media Count : 90

Abstract : A numerical model of thermal convection for a two-dimensional laminar, non-linear, non-rotating, incompressible, viscous fluid contained in a rectangle and heated non-uniformly from below is investigated. Two studies are made, one for a stress free bottom boundary and the other for a constant applied stress along the bottom. The Boussinesq equations are integrated numerically by means of the explicit scheme of DuFort and Frankel (1953) and in each case the top and side boundaries are both insulating and rigid. In the first study the dependence of the cellular convective motion and isotherms upon the Prandtl number and the horizontal Rayleigh number, Ra, is examined. A single asymmetric convective cell develops as the Rayleigh number is increased. The asymmetry and intensity of the circulation increases markedly with increasing horizontal Rayleigh number but respond slightly to changes in the Prandtl number. The bottom boundary layer thickness is also examined and is found to decrease as the Rayleigh number increases. In the second study, calculations are presented for a single Rayleigh number and Prandtl number and a moderate range in applied stress. The stress is applied in opposition to the thermal driving. As the stress increases, the thermal circulation weakens and the opposing circulation becomes stronger. The increase in stress results in a change from a thermal to a dual, containing both thermal and stress driven circulations of the same magnitude, to a stress driven circulation. (Author)

Descriptors :   (*OCEAN CURRENTS, MATHEMATICAL MODELS), (*LAMINAR BOUNDARY LAYER, INCOMPRESSIBLE FLOW), CONVECTION(HEAT TRANSFER), VISCOSITY, PRANDTL NUMBER, DIFFERENTIAL EQUATIONS, VORTICES, WIND, CURVE FITTING, THESES

Subject Categories : Physical and Dynamic Oceanography
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE