Sprinkler, smoke & heat vent, draft curtain interaction :

Abstract

Executive SummaryThis study was the result of a coordinated public-private research effort to gain insight into the interaction of sprinklers, roof vents and draft curtains through fire experiments and numerical modeling. The work was conducted over a period of two years.The International Fire Sprinkler, Smoke and Heat Vent, Draft Curtain Fire Test Project organized by the National Fire Protection Research Foundation (NFPRF) brought together a group of industrial sponsors to support and plan a series of large scale tests to study the interaction of sprinklers, roof vents and draft curtains of the type found in large warehouses, manufacturing facilities, and warehouse-like retail stores. A Technical Advisory Committee consisting of representatives from the sponsoring organizations, the National Institute of Standards and Technology (NIST), and other interested parties planned 39 large scale fire tests that were conducted in the Large Scale Fire Test Facility at Underwriters Laboratories (UL) in Northbrook, Illinois. The tests were designed to address relatively large, open-area buildings with flat ceilings, sprinkler systems, and roof venting with and without draft curtains. To simulate these conditions in the 37 m by 37 m by 15 m high (120 ft by 120 ft by 48 ft high) main test bay, the vents, draft curtains and sprinklers were installed on a 30 m by 30 m (100 ft by 100 ft) adjustable-height platform, 7.6 m (25 ft) off the floor. During the tests, smoke and hot gases filled the volume enclosed by the draft curtains, and the excess smoke flowed around the edges of the platform into a plenum space above. The smoke in the plenum spaced was continually exhausted through a smoke abatement system.Funding for the large scale tests, although substantial, permitted only five high rack storage commodity fire tests to be conducted. In order to best prepare for these tests and to add to the information available for model development and verification, 34 easily conducted and controlled heptane spray burner tests were also performed. Recognizing that the resources in terms of funding and time were limited, the NFPRF Technical Advisory Committee reduced the number of parameters in this study by selecting one commodity, one rack configuration and ignition source, a single sprinkler system and one sprinkler discharge density, one commercial vent design, and one vent/draft curtain arrangement.In parallel with the large scale fire tests, a program was conducted at NIST to develop a numerical field model, Industrial Fire Simulator (IFS), that incorporated the physical phenomena of the experiments. A series of bench scale experiments was conducted to develop necessary input data for the model. These experiments generated data describing the burning rate and flame spread behavior of the cartoned plastic commodity, thermal response parameters and spray pattern of the sprinkler, and the effect of the water spray on the burning commodity. Simulations were first performed for the heptane spray burner tests, where they were shown to be in...

Numerial simulation of the Howard Street Tunnel fire, Baltimore, Maryland, July 2001

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Evaluation of the ability of fire dynamic simulator to simulate positive pressure ventilation in the laboratory and practical scenarios

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Numerical Simulation of Sprinkler Suppression of Rack Storage Fires

“…It is physics based, as opposed to Refs. [3,4], where empirical correlations for water suppression were adopted.…”

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