A numerical study on heat release rate in a multichannel parallel test system for smoke spillover from the tunnel rescue station

2017 ◽  
pp. 503-507 ◽  
Author(s):  
Ya Liu ◽  
Wanfu Liu ◽  
Weiping Han ◽  
Jianjun Xia ◽  
Kai Yao ◽  
...  
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Numerical Study ◽  
Test System ◽  
Parallel Test

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

Influence of wavy enclosure and nanoparticles on heat release rate of PCM considering numerical study

2020 ◽  
Vol 319 ◽  
pp. 114121 ◽  
Author(s):  
Yu-Ming Chu ◽  
Dhananjay Yadav ◽  
Ahmad Shafee ◽  
Zhixiong Li ◽  
Quang-Vu Bach
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Numerical Study

scholarly journals Numerical Study on the Effect of Tunnel Aspect Ratio on Evacuation with Unsteady Heat Release Rate Due to Fire in the Case of Two Vehicles

Energies ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 133 ◽  
Author(s):  
Younggi Park ◽  
Youngman Lee ◽  
Junyoung Na ◽  
Hong Sun Ryou
Keyword(s):  
Aspect Ratio ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Numerical Study ◽  
Longitudinal Direction ◽  
Release Rates ◽  
Aspect Ratios ◽  
Visibility Distance ◽  
Computational Fluid Dynamics Analysis

In this study, the characteristics of fires in case of two vehicles in a tunnel are analyzed by Computational Fluid Dynamics analysis for varying tunnel aspect ratios. Unsteady heat release rates over time are set as the input conditions of fire sources considering real phenomena. Unsteady heat release rate values are obtained from experiments. As a result, the smoke velocities above the fire source appear faster in the case of tunnels with a large aspect ratio because the higher the height of the tunnel, the faster the smoke velocity caused by buoyancy forces. The smoke velocity in the longitudinal direction increases quickly. However, the temperature distribution in the vicinity of the ceiling is low when the tunnel aspect ratio is large because the height of the tunnel is not directly affected by the flames. Also, the higher the height of the tunnel, the lower the visibility distance due to the heat and smoke coming down along the wall surface. However, in the tunnels represented in this study, it is considered that the visibility of evacuees is sufficiently secured.

scholarly journals Numerical study of the laminar flame propagation in ethane-air mixtures

2014 ◽  
Vol 12 (3) ◽  
pp. 391-402 ◽  
Author(s):  
Venera Giurcan ◽  
Domnina Razus ◽  
Maria Mitu ◽  
Dumitru Oancea
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Laminar Flame ◽  
Numerical Study ◽  
Flame Temperature ◽  
Chemical Species ◽  
Main Reaction ◽  
Flame Thickness ◽  
Wide Range

AbstractThe structure of premixed free one-dimensional laminar ethane-air flames was investigated by means of numerical simulations performed with a detailed mechanism (GRI-Mech version 3.0) by means of COSILAB package. The work provides data on ethane-air mixtures with a wide range of concentrations ([C2H6] = 3.0–9.5 vol.%) at initial temperatures between 300 and 550 K and initial pressures between 1 and 10 bar. The simulations deliver the laminar burning velocities and the profiles of temperature, chemical species concentrations and heat release rate across the flame front. The predicted burning velocities match well the burning velocities measured in various conditions, reported in literature. The influence of initial concentration, pressure and temperature of ethane-air mixtures on maximum flame temperature, heat release rate, flame thickness and peak concentrations of main reaction intermediates is examined and discussed.

scholarly journals Numerical Study of the Effects of the Jet Fan Speed, Heat Release Rate and Aspect Ratio on Smoke Movement in Tunnel Fires

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1206
Author(s):  
Ha Thien Khieu ◽  
Young Man Lee ◽  
Ji Tae Kim ◽  
Hong Sun Ryou
Keyword(s):  
Aspect Ratio ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Numerical Study ◽  
Smoke Movement ◽  
Tunnel Fires ◽  
Jet Fan ◽  
Fan Speed ◽  
Set Up

In this study, the effects of the jet fan speed, heat release rate and aspect ratio on smoke movement in tunnel fires have been investigated. The jet fan speed was changed from 6.25 (25%) to 12.5 m/s (50%), 18.75 m/s (75%), and 25 m/s (100%). The heat release rate was set up from 3.9 to 6 MW and 16 MW, the aspect ratio was changed from 0.6 to 1 and 1.5, respectively. The lower the jet fan speed is, the longer the smoke back-layering length is. With a higher velocity, the smoke tends to move out of the tunnel quickly; however, smoke stratification also occurs, and this reduces visibility. This could make it difficult for people to evacuate. With a higher heat release rate, the smoke tends to move far away from the fires quickly when compared with other cases. Additionally, the higher the heat release is, the longer the smoke back-layering is. Finally, with a higher aspect ratio, the smoke back layering length in the tunnel is also longer. The smoke layer thickness is also larger than in other cases. The correlation of velocity, heat release rate and aspect ratio has been investigated to avoid the smoke back layer length in tunnel fires.

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