Use of the mass spectrometer for heat release rate analysis in fire calorimeters

Abstract This paper presents a coupled numerical investigation to assess the reaction to fire performance and fire resistance of various types of epoxy resin (ER) based composites. It examines the fire response of carbon fibre (CF) reinforced ER (CF/ER), ER with graphene nanoplatelets (GNP/ER) and CF reinforced GNP/ER (CF/GNP/ER). Thermal, physical and pyrolysis properties are presented to assist numerical modelling that is used to assess the material ability to pass the regulatory vertical burn test for new aircraft structures and estimate in-fire and post-fire residual strength properties. Except for the CF/GNP/ER composite, all other material systems fail the vertical burn test due to continuous burning after removal of the fire source. Carbon fibres are non-combustible and therefore reduce heat release rate of the ER composite. By combining this property with the beneficial barrier effects of graphene platelets, the CF/GNP/ER composite with 1.5 wt% GNP and 50 wt% CF self-extinguishes within 15 s after removal of the burner with a relatively small burn length. Graphene drastically slows down heat conduction and migration of decomposed volatiles to the surface by creating improved char structures. Thus, graphene is allowing the CF/GNP/ER composite panel to pass the regulatory vertical burn test. Due to low heat conduction and reduced heat release rate, the maximum temperatures in the CF/GNP/ER composite are low so the composite material retains very high in-fire and post-fire mechanical properties, maintaining structural integrity. In contrast, temperatures in the CF/ER composite are much higher. At a maximum temperature of 86 °C, the residual in-fire tensile and compressive mechanical strengths of CF/GNP/ER are about 87% and 59% respectively of the ambient temperature values, compared to 70% and 21% respectively for the CF/ER composite that has a temperature of 140 °C at the same time (but the CF/ER temperature will be higher due to continuing burning). Converting mass losses of the composites into char depth, the post-fire mechanical properties of the CF/GNP/ER composite are about 75% of the ambient condition compared to about 68% for the CF/ER composite.

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Combustion Characteristics, Emissions and Heat Release Rate Analysis of a Homogeneous Charge Compression Ignition Engine with Exhaust Gas Recirculation Fuelled with Diesel

Energy & Fuels ◽

10.1021/ef801010m ◽

2009 ◽

Vol 23 (5) ◽

pp. 2396-2404 ◽

Cited By ~ 8

Author(s):

Miguel Torres García ◽

Francisco J. Jiménez-Espadafor Aguilar ◽

Tomás Sánchez Lencero

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Exhaust Gas Recirculation ◽

Combustion Characteristics ◽

Exhaust Gas ◽

Compression Ignition ◽

Compression Ignition Engine ◽

Rate Analysis ◽

Gas Recirculation

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Fire Performance of Nylon Nanocomposites Fabricated by Melt Intercalation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.334-335.737 ◽

2007 ◽

Vol 334-335 ◽

pp. 737-740

Author(s):

Russel J. Varley ◽

Andrew M. Groth ◽

Kok Hoong Leong

Keyword(s):

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Fire Performance ◽

Fire Retardancy ◽

Cone Calorimetry ◽

Char Layer ◽

Transmission Electron ◽

Peak Heat Release Rate ◽

In Fire

This paper presents results of a study carried out to evaluate the effects of an organomodified nanoclay, either on its own or in combination with a polyimide, upon the fire performance of a commercially available nylon. The fire performance, as determined using cone calorimetry showed that up to 40% improvement in the peak heat release rate could be achieved at addition levels of only around 5wt% of nanoclay. The level of improvement was shown to be strongly dependent upon nanoscale dispersion with a more highly exfoliated morphology, as determined using transmission electron microscopy, which showed a greater reduction in the peak heat release rate compared to a more ordered intercalated structure. Investigation of the mechanism of fire retardancy showed that the reduction in the heat release rate is due to the nanoclay reinforcing the char layer which prevented combustible products from entering in to the gaseous phase. Generally, though, the time to ignition is unaffected by nanoclay additions. The addition of the polyimide to the nanoclay reinforced nylon was inconclusive showing little evidence of further improvements in fire performance.

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Effects of User Dependence on the Prediction Results of Visibility in Fire Simulations

Fire Science and Engineering ◽

10.7731/kifse.b5e493d9 ◽

2021 ◽

Vol 35 (3) ◽

pp. 14-22

Author(s):

Ho-Sik Han ◽

Sun-Yeo Mun ◽

Cheol-Hong Hwang

Keyword(s):

Sensitivity Analysis ◽

Heat Release ◽

Heat Release Rate ◽

Release Rate ◽

Large Change ◽

Fire Simulation ◽

Input Parameters ◽

Measurement Uncertainties ◽

Safety Assessments ◽

In Fire

To improve the reliability of safety assessments in domestic performance-based designs (PBDs), the problem of the input parameters being dependent on fire-simulation users was quantitatively analyzed. Thus, the results of statistical analyses of domestic PBD reports evaluated over the last 5 years were examined. It was determined that the uncertainties of the input parameters might have a relatively larger influence on the statistical deviations than the measurement uncertainties. Accordingly, a sensitivity analysis was performed by considering the statistical deviations of the input parameters that could greatly influence the prediction results of visibility, which are important for the available safe egress time. The main results were as follows: a large change in visibility was observed owing to deviations of the heat release rate and soot yield. Based on this study, it is expected that more accurate results can be obtained if the objectivity of input parameters determined by user dependence can be secured in domestic PBDs.

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