Laminar and turbulent natural convection heat transfer in Trombe wall channels

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:6891522

Chen, T D.T.

The natural convective heat transfer and air movement in a Trombe wall solar passive system has been studied analytically and numerically. Three Trombe wall channel geometries including the parallel channel with axial inlet and exit, parallel channel with side vents and Trombe wall channel coupled to the room have been considered. For the parallel channel with axial inlet and exit geometry, a momentum integral method has been used to solve parabolic governing equations for two-dimensional laminar flow. This formulation leads to a second order ordinary differential equation for pressure defect in the Trombe wall channel. The solution of this equation leads to prediction of velocity, temperature and pressure fields, and Nusselt number correlations that are in good agreement with previously reported finite difference solution of natural convection boundary layer equations. For the side-vented channel case, results are obtained for both two-dimensional laminar and turbulent natural convective flow regimes. Due to presence of recirculating flow patterns in this geometry, full Navier-Stokes equations in two-dimensions are employed. The turbulent flow characteristics are modeled by a two-equation (k-[epsilon]) model. The governing equations for steady laminar as well as turbulent flows are solved by a finite volume technique that uses the quadratic upwind differencing scheme to discretize non-linear governing equations to form algebraic equations which govern physical variables at the various numerical grid points. The coupled algebraic equations are solved by a semi-implicit algorithm known as SIMPLER. Flow patterns, isotherms and heat transfer characteristics are obtained for aspect ratios of 10 and 20, and Grashof number ranging from 1.4 x 10[sup 3] to 1.4 x 10[sup 8].

• Research Organization: Old Dominion Univ., Norfolk, VA (United States)
• OSTI ID: 6891522
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140901* -- Solar Thermal Utilization-- Space Heating & Cooling
42 ENGINEERING
420400 -- Engineering-- Heat Transfer & Fluid Flow
COMPUTERIZED SIMULATION
CONVECTION
ENERGY SYSTEMS
ENERGY TRANSFER
EQUIPMENT
HEAT TRANSFER
HEATING SYSTEMS
MASS TRANSFER
NATURAL CONVECTION
PASSIVE SOLAR COOLING SYSTEMS
PASSIVE SOLAR HEATING SYSTEMS
SIMULATION
SOLAR COOLING SYSTEMS
SOLAR EQUIPMENT
SOLAR HEATING SYSTEMS
TROMBE WALLS
WALLS