Transient performance analysis of a model building integrated with a Trombe-wall

Abstract

The objective of this study is to investigate the temperature behavior of a hypothetical two-story building with a total floor area of 120 m2 by modeling and simulation with TRNSYS (Transient System Simulation) program. A vented Trombe wall is used on the south façade of the ground floor. Additionally a direct gain window of area 6.5 m2 is placed on the south façade of the First floor. The hourly indoor temperature variations on the ground floor are determined. It is assumed that the model building is located in Larnaca, Cyprus. The results of the simulation show that approximately 95% of the total heating demand of the 60m2-zone can be met by a vented Trombe wall of area 15m2. It is verified that thermally insulating the building with 5cm-thick extruded polystyrene improves the thermal comfort by approximately 17%. It is observed that with a Trombe wall of area 15m2, the room air temperature can be easily maintained in the range between 19 and 21.5 °C, whereas the temperature on the First floor fluctuates between 17.3 and 20.5 °C during the coldest days of winter while the outside temperature ranges between 4 and 14°C. The Life Cycle Cost (LCC) analysis indicates that constructing a 15m2 Thermal storage wall in Cyprus is economically feasible compared to installing a 3-kW gas heater, as the saving-to-investment ratio is found to be 2.3.