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Zone Fire Modeling With Natural Building Flows and a Zero Order Shaft Model (NISTIR 5251)



J H. Klote, Glenn P. Forney


This paper addresses applications of zone fire models to simulate smoke flow in multistory buildings. Natural flows in buildings are discussed. A zero order model for shaft smoke flow was developed which treated the shaft as one perfectly mixed zone. A two zone fire model was modified to simulate natural flows and the zero order shaft smoke flow. The extent to which the one zone model and the two zone model are appropriate to simulate smoke flow in shafts is disucssed. The modifications for the natural building flow included development of new initial conditions and of the capability to simulate the gross effects of a heating and air conditioning system. Eighteen example zone model simulations were made to develop insight into the program modifications.
NIST Interagency/Internal Report (NISTIR) - 5251
Report Number


zone models, air movement, fire models, smoke movement, stairwells


Klote, J. and Forney, G. (1993), Zone Fire Modeling With Natural Building Flows and a Zero Order Shaft Model (NISTIR 5251), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 23, 2024)
Created September 1, 1993, Updated November 10, 2018