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Author
Zukoski, E. E. | Kubota, T.
Title
Experimental Investigation of the Heat Transfer from Buoyant Gas Plume to a Horizontal Ceiling. Part 2. Effects of Ceiling Layer. Quarterly Progress Report. June 1975-September 1975.
Coporate
California Inst. of Tech., Pasadena
Sponsor
National Bureau of Standards, Gaithersburg, MD
Report
NBS GCR 77-98, 1975, 78 p.
Distribution
Available from National Technical Information Service
Contract
GRANT-59004
Keywords
buoyant plumes | ceilings | compartment fires | fire plumes | heat transfer | room fires | scale models
Abstract
This report contains the results of experiments carried out as part of a study of heat transfer to room ceilings under conditions similar to those encountered in the early stages of a room fire before the room becomes completely involved in flames. Part 1 of this study was concerned with heat transfer to a bare ceiling and scaling procedures were developed there which gave complete modeling rules for this example. The reported here differs from this previous effort because side walls are used in the present experiments and they trap a thick layer of hot gas under the ceiling. This hot gas layer (the ceiling layer) will affect the temperature and momentum flux in the fire plume and hence the initial conditions for the ceiling jet formed by the impingement of the plume on the ceiling. It will also affect the temperature level in the ceiling jet since hot gas rather that cool air will be entrained. This report presents data obtained with two configurations of side walls, on axisymmetric Curtain Wall and a Model Room with a single (door) opening. Temperature and heat transfer data are presented and certain elements of a scaling model are discussed. A complete scaling model is still being developed and will be the subject of a later report.