||Development of a procedure to evaluate the air leakage distribution from fan pressurization test - validation of three airflow models
||A number of airflow models have been developed to assist the designer in the design of energy efficient and healthy built environment. The models range from very simple empirical algorithms to calculate the global airflow rate to sophisticated computerized fluid-dynamic techniques solving the Navier-Stokes equations. The multi-zone approach falls between these two extreme cases. This approach assumes that the interior of the building is divided into regions of differing pressures interconnected by leakage paths. The advantage of multi-zone models, besides being able to simulate infiltration in larger buildings, is that they can be used to calculate mass flow interactions between the different zones inside buildings as well as inside and outside. This knowledge is needed for the design of heating/cooling and ventilation systems. An essential part of the development of any computer model is its validation, and the essential information needed for validation of airflow models is the distribution of air leakage distribution. This paper first describes a methodology to distribute global air leakage of whole house and whole garage among cracks and gaps on exterior walls and roof, and report the validation of three airflow models. From the comparisons it can be seen that there are good agreement between the predictions made by the models and measured data, as well as between three models. Therefore, it can be concluded that the methodology for air leakage distribution is correct, and the performances of COMIS, CONTAM and ESP-r for predicting airflow rates in single-family house are similar.
|Year of publication:
Haghighat F (2003).
Development of a procedure to evaluate the air leakage distribution from fan pressurization test - validation of three airflow models. Amor R (editor) Proceedings of the CIB W78's 20th International Conference on Construction IT, Construction IT Bridging the Distance, CIB Report 284, ISBN 0-908689-71-3, Waiheke Island, New Zealand, 23-25 April 2003, pg. 137-145. (ISSN: 2706-6568),