Radiant heat flux to external surfaces from escaping and extrusive flashover flames

Author(s):  
A Chen ◽  
J Francis

Current practice when predicting safe separation distances between buildings is to assess the radiant hazard posed by flames and hot gas visible across the vent. The vent is treated as a radiating vertical surface with a representative temperature. A method is proposed for calculating the radiant heat flux to external surfaces from hot gas and extrusive flame emerging from a vent in a compartment wall containing post-flashover fire. An experimental study has been made to examine the validity of the method for extrusive flames unaffected by wind.

Author(s):  
В.А. Архипов ◽  
С.А. Басалаев ◽  
Н.Н. Золоторёв ◽  
К.Г. Перфильева ◽  
А.С. Усанина

New method for determining the evaporation rate of single levitating drop at radiant heat flux has been proposed. The results of experimental study of the evaporation rate of distilled water drop upon heating by radiant and convective heat flux in the range of q = (0.25–1.5) W/cm^2 are presented. Comparative analysis of the features of the drop evaporation during radiant and convective heating has been carried out.


2021 ◽  
Vol 159 ◽  
pp. 106605 ◽  
Author(s):  
Xianjia Huang ◽  
Yuhong Wang ◽  
He Zhu ◽  
Le He ◽  
Fei Tang ◽  
...  

2014 ◽  
Vol 28 (2) ◽  
pp. 26-33
Author(s):  
Soo-Young Park ◽  
Hee-Won Seo ◽  
Dae-Hoi Kim ◽  
Nam-Woong Wang ◽  
In-Hwan Yeo ◽  
...  

Author(s):  
В.К. Абгарян ◽  
М.В. Абгарян ◽  
А.Б. Надирадзе ◽  
В.В. Нигматзянов ◽  
А.А. Семенов

The radiant heat flux coming from the discharge plasma on the surfaces of radio frequency ion thrusters is considered. Spontaneous emission of photons is formed when the excitation of plasma atoms and ions is removed. The distributions of the densities of the heat flux brought by radiation to the surface in the thrusters are calculated. The distributions can be used in numerical calculations of temperatures in thrusters design.


2017 ◽  
Vol 21 (4) ◽  
pp. 1665-1671 ◽  
Author(s):  
Meng Chen ◽  
Fanglong Zhu ◽  
Qianqian Feng ◽  
Kejing Li ◽  
Rangtong Liu

The effects of absorbed moisture on thermal protective performance of fire-fighters? clothing materials under radiant heat flux conditions were analyzed in this paper. A thermal protective performance tester and temperature sensor were used to measure the temperature variations for the facecloth side of four kinds of commonly used flame retardant fabrics in several radiant heat exposures, which varied in moisture content. Experimental results showed that, all of the temperature profiles of these four kinds of moistened fabrics under different radiant heat flux conditions presented the same variation trend. The addition of moisture had a positive influence on the thermal protective performance during the constant temperature period when heat radiation time was more than 60 seconds. As the heat radiation time increased beyond 500 seconds, the thermal protective performance of moistened fabrics became worse than that of dried fabrics in general.


2021 ◽  
pp. 073490412110366
Author(s):  
Junhui Gong ◽  
Hongen Zhou ◽  
Hong Zhu ◽  
Conor G McCoy ◽  
Stanislav I Stoliarov

Oriented strand board is a widely used construction material responsible for a substantial portion of the fire load of many buildings. To accurately model oriented strand board fire response, kinetics and thermodynamics of its thermal decomposition and combustion were carefully characterized using milligram-scale testing in part I of this study. In the current work, Controlled Atmosphere Pyrolysis Apparatus II tests were performed on representative gram-sized oriented strand board samples at a range of radiant heat fluxes. An automated inverse analysis of the sample temperature data obtained in these tests was employed to determine the thermal conductivities of the undecomposed oriented strand board and condensed-phase products of its decomposition. A complete pyrolysis model was formulated for this material and used to predict the mass loss rates measured in the Controlled Atmosphere Pyrolysis Apparatus II experiments. These mass loss rate profiles were predicted well with the exception of the second mass loss rate peak observed at 65 kW m−2 of radiant heat flux, which was underpredicted. To further validate the model, cone calorimeter tests were performed on oriented strand board at 25 and 50 kW m−2 of radiant heat flux. The results of these tests, including both mass loss rate and heat release rate profiles, were predicted reasonably well by the model.


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