A study of forward smolder ignition of polyurethane foam

Anthenien, Ralph A.; Fernandez‐Pello, A. C.

doi:10.1016/s0082-0784(98)80124-0

Cited by 17 publications

(13 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A threshold temperature is not valid sole criterion for ignition of smoldering but it is part of a multi-criteria signature [Anderson et al 2000]. Several experimental studies have found that the minimum temperature measured during ignition of polyurethane foam is in range from 300 to 450 ˚C [Hadden et al 2012, Anderson et al 2000, Anthenien and Fernandez-Pello 1998]. This is much lower than the surface temperature of 600 °C required for spontaneous flaming ignition of the same material [Hadden et al 2012].…”

Section: Radiant Ignitionmentioning

confidence: 99%

“…This law originates from the time it takes for heat conduction to result in a critical temperature at a key location. For flaming, the key location is the free surface of the fuel, but for smoldering the key location is inside the fuel bed, at a sufficient depth such that an insulating layer of char is formed over the oxidation front [Anthenien and Fernandez-Pello 1998]. The concept of a critical depth for ignition is not sufficiently studied yet but could be expected to vary for different materials and external conditions in the scale from 1 cm to 10 cm roughly.…”

Section: Radiant Ignitionmentioning

confidence: 99%

“…Heat is transferred by conduction, but in porous fuels, natural and forced convection also play a role. Anthenien and Fernandez-Pello [1998] studied the initiation of smoldering using an electric heater in contact with a sample of polyurethane foam under forced airflow. Ignition was reported at heat fluxes as low as 3 kW/m 2 and the relationship between time to ignition and heat flux was also shown to follow a q −1 2 ⁄ law.…”

Section: Conductive Ignitionmentioning

confidence: 99%

See 2 more Smart Citations

Smoldering Combustion

Rein¹

2016

SFPE Handbook of Fire Protection Engineering

102

View full text Add to dashboard Cite

His professional activities are centered on research in fire and combustion, and teaching of thermofuild sciences to engineers. He has studied a wide range of fire dynamics topics in the built and the natural environments, including pyrolysis, fire modeling, wildfires, structures and fire, and forecasting techniques. Over the course of the last 15 years he has also specialized in smoldering combustion, conducting both computational and experimental studies on a variety of fuels like polyurethane foam, cellulose, peat and coal.

show abstract

Section: Radiant Ignitionmentioning

confidence: 99%

Section: Radiant Ignitionmentioning

confidence: 99%

Section: Conductive Ignitionmentioning

confidence: 99%

See 1 more Smart Citation

Smoldering Combustion

Rein¹

2016

SFPE Handbook of Fire Protection Engineering

102

View full text Add to dashboard Cite

show abstract

“…the heating by the igniter of the pyrolyzed foam or char left behind by the smolder reaction. Experimental evidence has shown that the ignition process itself is relatively insensitive to oxidizer velocity, therefore the gas convective term is neglected [22]. An undetermined parameter in Eq.…”

Section: = X S We Have T = T S (Opposed) T = T P (Forward)mentioning

confidence: 99%

Smolder ignition of polyurethane foam: effect of oxygen concentration

Walther¹,

Anthenien²,

Fernandez‐Pello³

2000

Fire Safety Journal

View full text Add to dashboard Cite

Experiments have been conducted to study the ignition of both forward and opposed smolder of a high void fraction, flexible, polyurethane foam in a forced oxidizer flow. Tests are conducted in a small scale, vertically oriented, combustion chamber with supporting instrumentation. An electrically heated Nichrome wire heater placed between two porous ceramic disks, one of which is in complete contact with the foam surface, is used to supply the necessary power to ignite and sustain a smolder reaction. The gaseous oxidizer, metered via mass flow controllers, is forced through the foam and heater. A constant power is applied to the igniter for a given period of time and the resulting smolder is monitored to determine if smolder is sustained without the assistance of the heater, in which case smolder ignition is considered achieved. Reaction zone temperature and smolder propagation velocities are obtained from the temperature histories of thermocouples embedded at predetermined positions in the foam with junctions placed along the fuel centerline. Tests are conducted with oxygen mass fractions ranging from 0.109 to 1.0 at a velocity of 0.1 mm/s during the ignition period, and 0.7 or 3.0 mm/s during the self-sustained propagation period. The results show a well defined smolder ignition regime primarily determined by two parameters: igniter heat flux, and the time the igniter is powered. These two parameters determine a minimum igniter/foam temperature, and a minimum depth of smolder propagation (char), which are conditions required for ignition to occur. The former is needed to establish a strong smolder reaction, and the latter to reduce heat losses from the incipient smolder reaction to the surrounding environment. The ignition regime is shifted to shorter times for a given igniter heat flux with increasing oxygen mass fraction. A model based on concepts similar to those developed to describe the ignition of solid fuels has been developed that describes well the experimental ignition results.3

show abstract

“…From a fire safety perspective, smoldering is a significant concern, as 25% of residential fire deaths in the United States are caused by fires originating from smoldering smoking materials [2]. A smolder reaction can be initiated by a heat source too weak to directly produce a flaming reaction [3][4][5] and releases toxic and flammable gases such as carbon monoxide, various heavy hydrocarbons and large oxygenated molecules [6,7].…”

Section: Introductionmentioning

confidence: 99%

The piloted transition to flaming in smoldering fire retarded and non‐fire retarded polyurethane foam

et al. 2008

View full text Add to dashboard Cite

The piloted transition from smoldering to flaming, though a significant fire safety concern, has not been previously extensively studied. Experimental results are presented on the piloted transition from smoldering to flaming in non-fire retarded (NFR) polyurethane foam and the fire retarded polyurethane foam Pyrell ® . The samples are small blocks, vertically placed in the wall of an upward wind tunnel. The free surface is exposed to an oxidizer flow and a radiant heat flux. The smolder product gases pass upwards through a pilot. The experiments on NFR foam show that the smolder velocity and peak smolder temperature, which increase with the oxygen concentration and heat flux, are strongly correlated to the transition to flaming event, in that there are minimum values of these parameters for transition to occur. The existence of a minimum smolder velocity for ignition supports the concept of a gaseous mixture reaching a lean flammability limit as the criterion for the transition to flaming. To compensate for the solid-and gas-phase effects of the fire retardants on the piloted transition in Pyrell, it was necessary to increase the oxygen concentration and the power supplied to the smolder igniter and the pilot. The piloted transition is observed in oxygen concentrations above 17% in NFR foam, and above 23% in Pyrell. The results show that although Pyrell is less flammable than NFR foam, it is still susceptible to smoldering and the piloted transition to flaming in oxygen-enriched environments, which is of interest for special applications such as future space missions.

show abstract

A study of forward smolder ignition of polyurethane foam

Cited by 17 publications

References 7 publications

Smoldering Combustion

Smoldering Combustion

Smolder ignition of polyurethane foam: effect of oxygen concentration

The piloted transition to flaming in smoldering fire retarded and non‐fire retarded polyurethane foam

Contact Info

Product

Resources

About