Design and simulation of an HVAC system for the CEDAT conference hall

Abstract

Indoor environmental quality (IEQ) is a vital parameter to account for in new and existing buildings since it greatly influences the indoor conditions of buildings. It is estimated that people spend approximately 90% of their time indoors. Thus, attempts have been made by building engineers and designers to implement strategies that improve the IEQ within buildings. Thermal comfort is one of the most important aspects of IEQ. Thermal comfort is affected by temperature, relative humidity (RH), and airspeed. These parameters are influenced by ventilation, fenestration, occupancy, building materials, and building orientation. Uganda has a tropical climate characterized by hot/warm temperatures for the most significant period of the year. During hot days, the contribution of construction materials, high occupancy densities, and inadequate ventilation to building heat gains becomes significant. This results in an increase in indoor temperatures and thus affects the thermal comfort of the building occupants. There is a need to design a cooling and mechanical ventilation system to supplement natural ventilation in buildings, so as to maximize air circulation and minimize heat gains. In this study, a cooling and mechanical ventilation system was designed for the CEDAT Conference Hall. Building data was obtained in addition to the measurement of indoor thermal comfort and air quality parameters including temperature, relative humidity, air speed, and CO2. The system was therefore designed based on the design requirements and results from the cooling load calculations. DesignBuilder software was then used as a simulation engine to test the system’s performance in achieving thermal comfort requirements.