Quantification of Airflow Patterns in a Naturally Ventilated Building Simulated in a Water Table Apparatus

Pooja Mundhe, Rashmin Mohan Damle, Prasad Vaidya, Michael G. Apte | 2018

Abstract

Today, most of the people spend 80-90% of the time indoors either in the office or at home. Indoor air is contaminated by human activities and building materials which emit volatile organic compounds. Exposure to these compounds has a short and long-term impact on health. It is therefore important to provide a healthy and productive indoor environment. Acceptable indoor air quality can be maintained by operating a building in natural ventilation, and this can also reduce energy consumption. The water table is an inexpensive, easily accessible apparatus that helps to analyze natural ventilation in buildings due to wind effect and provides instantaneous two-dimensional results of airflow patterns in and around the building. This paper provides and tests a methodology to objectively quantify the images from the water table simulations and calculate results for ventilation metrics like percentage of dead spots, absolute ventilation efficiency, air changes per hour, dose and room mean age of air that quantifies air movement within a physical building model simulated in the apparatus. The quantitative method will help for comparative analysis between design options and make design decisions in terms of opening sizes, orientation, and appropriate positioning of openings optimized for wind-driven naturally ventilated buildings.