The Increase in the Maximum Heat-Release Rate and Apparent Flame Strength of Opposed-Jet Diffusion Flames Under Impressed Electric Fields

1966 ◽  
Vol 88 (2) ◽  
pp. 157-164
Author(s):  
Bernard J. Rezy ◽  
Robert J. Heinsohn
Keyword(s):  
Electric Field ◽  
Heat Release ◽  
Electric Fields ◽  
Heat Release Rate ◽  
Release Rate ◽  
Field Experiments ◽  
Diffusion Flames ◽  
Maximum Heat ◽  
Jet Diffusion Flames ◽  
Opposed Jet

This paper is concerned with a study of the behavior of opposed-jet diffusion flames subjected to electrostatic fields. A theory for an idealized diffusion flame is presented which predicts an increase in the maximum volumetric heat-release rate when a flame is subjected to an electric field. Experiments reveal that the maximum mass flow into the flame increases with the application of an electric field.

Retardant Properties of Nanosilica/PTFE Nanoparticals-Reinforced Polypropylene

2014 ◽  
Vol 1004-1005 ◽  
pp. 77-84 ◽  
Author(s):  
Zhen Lu Zhang ◽  
Dong Li Li ◽  
Wen Cai Xu ◽  
Ya Bo Fu ◽  
Rui Juan Liao
Keyword(s):  
Mass Loss ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Thermoplastic Polymer ◽  
Maximum Heat ◽  
Average Mass ◽  
Melting Characteristics

This work reports the flammability properties of Nanocomposites reinforced with silica and PTFE nanoparticles and toughened with an elastomeric ethylene-vinyl acetate (EVA). Through trial and simulation study of the flame retardant thermoplastic polymer and melting characteristics of PP in the combustion process.The study found that modified PP composites have good flame retardancy compared to PP in case of fire relatively.In the study,the melting characteristics of the thermoplastic polymer affected the mass loss rate in the combustion stage.Nanocomposites experienced low plastic mass loss compared with PP, this has been related to pyrolysis mechanism of polymer.In general,The polymers undergoing depolymerization will lead to a rapid volatilization and therefore experienced much less melting.The results showed that:total heat release of nanocomposites was higher than polypropylene, while the average heat release rate, the maximum heat release rate, the average effective heat of combustion, the average mass loss rate, the average specific extinction area, and other indicators were lower than polypropylene.

scholarly journals Estimation of Magnitude and Heat Release Rate of Fires Occurring in Historic Buildings-Taking Churches as an Example

2021 ◽  
Vol 13 (16) ◽  
pp. 9193
Author(s):  
Wen-Yao Chang ◽  
Chieh-Hsin Tang ◽  
Ching-Yuan Lin
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Water Mist ◽  
Smoke Detector ◽  
Fire Dynamics ◽  
Historical Building ◽  
Maximum Heat ◽  
Improvement Measures ◽  
Maximum Heat Release

Historical buildings often fail to meet today’s building and fire protection regulations due to their structure and space restrictions. For this reason, if such buildings encounter fire, serious damage will be resulted. The fire of the Notre-Dame Cathedral in Paris (Notre-Dame de Paris) in April 2019 highlights the seriousness of this problem. In this study, the historical building of “Tamsui Church” was selected as an example. The Fire Dynamics Simulator (FDS) was adopted to analyze the scale of damage and possible hazards when the wooden seats in the church are on fire, and improvement measures were proposed to ensure that such buildings can be used under safer conditions. It was found that the existing seat arrangement will cause the spreading of fire, and the maximum heat release rate is 2609.88 kW. The wooden roof frame above the fire source will also start to burn at 402.88 s (6.6 min) after the fire, which will lead to a full-scale fire. To maintain the safety of the historical building, it is necessary to add active firefighting equipment (smoke detector and water mist system).

scholarly journals A Numerical Study on the Effect of Volume Change in a Closed Compartment on Maximum Heat Release Rate

2017 ◽  
Vol 31 (5) ◽  
pp. 19-27
Author(s):  
Hong-Seok Yun ◽  
◽  
Dong-Gun Nam ◽  
Cheol-Hong Hwang ◽  
◽  
...  
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Volume Change ◽  
Release Rate ◽  
Numerical Study ◽  
Maximum Heat ◽  
Maximum Heat Release

scholarly journals Differences between Free and Compartment Burning of Furniture Part 2 Maximum Heat Release Rate and Fire Growth Rate

2007 ◽  
Vol 26 (4) ◽  
pp. 523-527
Author(s):  
Akihide Jo ◽  
Takayuki Orito ◽  
Norichika Kakae ◽  
Yoshifumi Ohmiya ◽  
Kaoru Wakatsuki
Keyword(s):  
Growth Rate ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Fire Growth ◽  
Maximum Heat ◽  
Maximum Heat Release

scholarly journals Flammability Characteristics of Green Roofs

Buildings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 126
Author(s):  
Nataliia Gerzhova ◽  
Pierre Blanchet ◽  
Christian Dagenais ◽  
Sylvain Ménard ◽  
Jean Côté
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Green Roof ◽  
Fire Risk ◽  
Green Roofs ◽  
Fuel Load ◽  
Growing Media ◽  
Maximum Heat ◽  
Flammability Characteristics

Assessing the fire risk of vegetated roofs includes the determination of their possible contribution to fire. Green roof components such as plants and growing media are organic materials and present a fuel that can catch and support the spread of fire. The flammability characteristics of these components were analyzed and compared to a typical roof covering. Growing media with 15% of organic matter were tested using cone calorimeter apparatus. The fuel load and heat release rate of the growing media were measured in both moist (30%) and dry conditions. It was observed that growing media in a moist condition do not present a fire risk, reaching a maximum heat release rate of 33 kW/m2. For dry substrates, a peak heat release rate of 95 kW/m2 was recorded in the first minute, which then rapidly decreased to 29 kW/m2 in the second minute. Compared to a typical bitumen roof membrane, the green roof showed a better fire performance. The literature data report more severe results for plant behavior, reaching peak heat release rates (HRRs) of 397 kW/m2 for dried and 176 kW/m2 for a green material. However, a rapid decrease in HRR to much lower values occurs in less than 2 min. The results also show that extensive and intensive types of green roofs present 22% and 95% of the additional fire load density when installed on a modified bitumen membrane, 19.7 and 85.8 MJ/m2, respectively.

Burning Behavior of Upholstered Furniture Mockups

1984 ◽  
Vol 2 (3) ◽  
pp. 205-235 ◽  
Author(s):  
John F. Krasny ◽  
Vytenis Babrauskas
Keyword(s):  
Heat Release ◽  
Combustion Product ◽  
Heat Release Rate ◽  
Flame Spread ◽  
Release Rate ◽  
Product Concentration ◽  
Light Olefin ◽  
Maximum Heat ◽  
Maximum Heat Release ◽  
Furniture Calorimeter

Furniture mockups consisting of various arrangements of full-size cushions were tested in the NBS furniture calorimeter. Measurements included heat release, combustion product concentrations, and flame spread characteristics. Major variations in burning were observed: neoprene mockups only smoldered, flame retardant treated polyurethane mockups burned more slowly than un treated mockups but eventually reached similar maximum heat release rates. Fabrics were ranked, in terms of maximum heat release rate and several other measured characteristics, from low to high: heavy cotton fabric; light cotton and heavy olefin, and light olefin. Flame spread rate measured on the mockups cor related with the time to reach a 100 kW heat release rate. Heat release rate and combustion product concentration generally increased with increasing number of cushions per mockup. Thinner cushions burned more rapidly than thicker ones.

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