Empirical and Dynamic Simulation-Based Assessment of Indoor Thermal Performance in Naturally Ventilated Buildings

This study attempts to investigate a parametric model to assess the thermal performance of naturally ventilated residential buildings for various parameters. A predictive model using DesignBuilder and Rhino is generated for 14 opening sizes in rooms along eight orientations in the hot-humid climate of Chennai city. The results of indoor temperature simulated from the model and collected from field measurements are compared and found to correlate well. The model is validated with two commonly used influencing factors, namely ceiling fan and flyscreen, and is found to correlate well with field measurements. The South-West room showed better thermal performance. For the same opening size in different room orientations, there is a temperature variation of 4 °C. The indoor average temperature is higher in rooms oriented along the cardinal directions than in the semi-cardinal directions. There is not much variation in indoor temperature for openings below 35%. Precautions must be taken to ensure that the outdoor temperature at site correlates with the EPW data. The model can be used to test the implications of the affecting factors to arrive at an optimized design at an early design stage resulting in enhanced thermal comfort. The results are useful in assessing the implications of changing one or more parameters on the indoor thermal performance in rooms with varying orientation and opening size. Since the model is based on the most prevailing and preferred building configurations, the study will assist architects and designers in optimizing for the most effective design of naturally ventilated buildings.