Radiative Heat Transfer and Radiative Properties of Composites
Knowledge of the radiative properties of composite materials is important in a number of practical applications [1-9]. Coatings of composite materials are widely used to enhance or to reduce radiative heat loss from a variety of systems. For example, heat loss from a furnace can be reduced significantly by applying high thermal emissivity ceramic-composite coating on the interior surface of the furnace chamber . The energy that is absorbed by the surface from hot gases is reemitted back to the furnace. High thermal emissivity composite coatings are also used in space applications. The spacecraft surfaces exposed to the space environment are coated with high-emissivity composite coatings to enhance the loss of heat generated due to high friction between the space vehicle surface and atmosphere . In several applications, the composite coatings are designed to have low thermal emissivity. For example, low-emissivity composite coatings are used on the under roof of the houses to help keep the attic area cool during summer. The heat from the sun is reflected back to the atmosphere.