View Factor Radiative Heating Model

The view factor radiative heating model is a general-purpose routine for computing the exchange of thermal radiant energy between opaque surfaces. The view factor model is applicable to any geometric configuration, regardless of the orientation and curvature of the radiating surfaces, and regardless of the presence of internal or external blockages.

 
Applications

The view factor radiation model is well suited for any application in which the thermal contrasts within your flow domain are large enough to warrant the inclusion of radiative heating as an important form of internal energy transfer. It can be used alone or in combination with the conjugate heat transfer model to investigate a number of classes of problems, including:

Evaluation of heating, air conditioning, and ventilation systems in residences, auditoriums, or other commercial or public buildings

Computation of the airflow and temperatures in furnaces, ovens, or similar heated chambers

Evaluation of insulation schemes for heated (or cooled) pipes, ducts, or structural components (e.g., walls)

Heat exchanger design for power production, waste heat recovery, and chemical processing applications

Heat sensor element design analyses

Mutual energy exchanges between N radiating surface elements in an arbitrary flow domain

Model Description

The view factor radiative heating model is based on a consideration of the net radiant energy exchange between individual computational elements lying on the interior surfaces of model geometries. These elements—which correspond exactly to the bounding walls of individual computational cells—are usually rectangular in shape, but can be of any size and orientation relative to each other. They can also be composed of different materials, have different temperatures, and absorb and emit thermal radiation differently by virtue of having different radiative properties.

The model consists of several components: (1) a model for the surface radiative energy flux and radiosity, (2) the view factor formulation, (3) a radiative obstruction model, (4) a set of simplifying assumptions, and (5) the energy conservation equation source term.