chapter  1
61 Pages

Airflow, heat and mass transfer in enclosures

This chapter describes the fundamental principles of airflow, heat and mass transfer phenomena that take place in buildings. The need of emphasizing multi-disciplinary nature is noted here. Much of the basic theory and concepts on airflow, heat and mass transfer are described in classical textbooks of heat transfer and fluid mechanics, with new developments reported in journals such as Journal of Heat Transfer, Journal of Fluid Mechanics and International Journal of Heat and Mass Transfer. Historically, the concepts and technologies developed in other engineering disciplines have also been successfully applied and extended to ventilation application. Examples include the application of the residence time concept (Danckwerts, 1952) developed in chemical engineering to ventilation efficiency (Sandberg, 1981) and the application of CFD originally developed for the aerospace industry (Nielsen, 1974). Contribution of the ventilation community to fluid mechanics and heat and mass transfer has also been evident, such as the development of non-isothermal jets (Koestel, 1955).