This paper describes an effort to formulate an understanding of the displacement ventilation scheme used by the Anasazi Indians over thousand years ago. The scheme uses a separate but connected air chamber linked to the outdoors through a narrow shaft located away from the outlet on top of the Kiva roof To create the necessary flow to overcome the friction in the system, a source of energy is needed. In winter, this source (a small fire) was sufficient to increase the air and Mean Radiant temperatures inside the Kiva to provide thermal comfort while creating a sufficient draft to remove Carbon Dioxide and other pollutants from the space. However, this configuration increases the temperature in summer beyond thermal comfort, making the likelihood for prolonged summer occupancies low. The paper illustrates the development of a mathematical model to predict the airflow regime inside the Kiva and the resulting air temperatures using a recursive set of formulae.
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