P2.9.26 Fire Gas Transport Phenomena Beneath Ceilings

Event

14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
Nürnberg/Nuremberg, Germany

Chapter

P2.9 Technology and Application

Author(s)

D. Gutmacher, J. Wöllenstein - Department of Microsystems (IMTEK) University of Freiburg (Germany), S. Künzli, U. Hoefer - Siemens Building Technologies (Switzerland)

Pages

1776 - 1779

DOI

10.5162/IMCS2012/P2.9.26

ISBN

978-3-9813484-2-2

Price

free

Abstract

We report on low-power gas sensors in fire safety applications and focus on the analysis of gas propagation behavior. We measured with a variety of gas sensors their performance and the spreading behavior of gas during fire test scenarios. We observed that during slow developing smoldering fires with low convection and especially when heat layers are generated at the ceiling, gases can be detected faster than smoke. The gas diffusion through a heat layer was measured with vertical sensor chains and the result has been simulated by Fick's law. A simulation of CO and H2 diffusion showed that diffusion is the main transport effect in the first two minutes until the turbulent buoyancies are forcing the convective flow into the heat layer.