The heat balance method for calculating space-cooling loads in a building consists of several major heat transfer processes. These include the radiative and convective exchange on the outside surface of each building element, the conduction through each element, the radiative interaction among all interior surfaces, and the convective transfer between the interior surfaces and the zone air. This paper focuses on the heat balance at the exterior surface of each building element. This balance includes many different types of interactions. Shortwave radiation and convection to the outside air are perhaps the most significant elements in the balance, but longwave radiation between the exterior surface and the sky, ground, and air plays a role in the process as well. All of these interactions must balance with the amount of heat being conducted through the building element. Implementation of these interactions into the heat balance method requires several mathematical models. These include models for solar radiation, air temperature, sky temperature, ground surface temperature, and the exterior convection coefficient. Presents many of the published models for these quantities and compares them both qualitatively and quantitatively. Additionally, a study is performed to determine the sensitivity of each element to the overall space-cooling load.

Units: Dual

KEYWORDS: year 1997, Outside, heat balance, calculating, cooling load, external walls, surfaces, emissivity, heat flow, algorithms, convection, heat gain, surface temperature, buildings