Estimation of Indoor Temperature for a Passive Solar Building with a Combined Passive Solar System

AbstractPassive solar design strategies for buildings are necessary for annual heating energy demand reduction. This paper presents a mathematical model for interior room temperature calculation of a building that integrates a combined passive solar system consisting of an unvented Trombe wall and a direct passive solar system for direct insolation. The model was applied to a residential building located in Niš, Serbia, which is not additionally heated by conventional fuels. Two variations of a combined passive system were taken into consideration. The first combined passive system consisted of a Trombe wall made of 0.45-m-thick concrete and the second combined passive system consisted of a 0.20-m-thick concrete Trombe wall. To calculate the complex mathematical model, depending on the size of the window opening, window slope (slanting or vertical position), and orientation of the room, two software packages were developed, RMSun and InSunTr. In addition, the indoor air temperatures of a thermally insulated residential building with an unvented Trombe wall and a direct passive solar system for different building orientations and different Trombe wall thicknesses were analyzed during the winter period between January and March.