Numerical analysis of combined buoyancy-induced and pressure-driven smoke flow in complex vertical shafts during building fires
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 1 August 2016
Abstract
Purpose
The purpose of this paper is to study the behavior of smoke flow in building fires and optimize the design of smoke control systems.
Design/methodology/approach
A total of 435 3-D fire simulations were conducted through NIST fire dynamics simulator to analyze thermal behavior of combined buoyancy-induced and pressure-driven smoke flow in complex vertical shafts, under consideration of influence of heat release rate (HRR) and locations of heat sources. This influence was evaluated through neutral pressure plane (NPP), which is a critical plane depicting the flow velocity distributions. Hot smoke flows out of shafts beyond the NPP and cold air flows into shafts below the NPP.
Findings
Numerical simulation results show that HRR of heat source has little influence on NPP, while location of heat source can make a significant difference to NPP, particularly in cases of multi-heat source. Identifying the location of NPP helps to develop a more effective way to control the smoke with less energy consumption. Through putting an emphasis on smoke exhausting beyond the NPP and air supplying below the NPP, the smoke control systems can make the best use of energy.
Research limitations/implications
Because of the chosen research approach, the research results may need to be tested by further experiments.
Practical implications
The paper includes implications for the optimization of smoke control systems design in buildings.
Originality/value
This paper fulfills an identified need to research the behavior of hot smoke in building fires and optimize the design of smoke control systems.
Keywords
Acknowledgements
This work was supported by National Key Basic Research Program of China (973 Program) (No. 2012CB719704), National Natural Science Foundation of China (No. 51323010) and the Fundamental Research Funds for the Central (No. WK2320000033).
Citation
Chen, Y., Zhou, X., Zhang, T., Fu, Z., Hu, Y. and Yang, L. (2016), "Numerical analysis of combined buoyancy-induced and pressure-driven smoke flow in complex vertical shafts during building fires", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 26 No. 6, pp. 1684-1698. https://doi.org/10.1108/HFF-11-2014-0355
Publisher
:Emerald Group Publishing Limited
Copyright © 2016, Emerald Group Publishing Limited