An experimental study on the burning rates of interacting fires in tunnels

Yozgatlıgil, Ahmet
Multiple fires may occur in close proximity in process industries, power generation and fuel storage facilities and confinement conditions such as tunnels, which can lead to a considerable alteration in fire characteristics and safety design. The topic is of significant importance to the fire safety research because there is little work in the literature that investigates the case of interacting fires, which have a destructive potential. In this work, we study the effects of an adjacent fire source on the burning rate and heat release rate characteristics of tunnel fires. Square ethanol pools of 10 and 15 cm in size and 0.22-1 cm in depth were used as fire sources in a reduced scale tunnel model. Ventilation to the tunnel was varied between 0 and 1.5 m/s. Pool fires were configured in single and dual pool orientations. Variations in the pool fire burning rates were discussed as being functions of pool size and depth, and a result of the interaction with the secondary fire. The maximum burning rate enhancement factor, defined as the ratio of the parameter for interacting fires to non-interacting ones, was shown to be 2.3. This was due to the enhancing effect of the secondary fire on the heat feedback to the fuel, and the increased combustion mass transfer. Tests with relatively larger pool sizes burned faster, with an advanced onset of the transition to a bulk boiling phase, which was attributed to the controlling heat feedback mechanism associated with the pool size.


An experimental study on the effects of blockage ratio and ventilation velocity on the heat release rate of tunnel fires
Kayili, Serkan; Yozgatlıgil, Ahmet; Cahit Eralp, O. (SAGE Publications, 2011-8-26)
It is very important to accurately predict the fire-induced air velocity, temperature, and smoke concentrations in tunnel fires to design efficient fire protection systems. In this study a scaled model of a tunnel was constructed based on Froude number scaling and wood sticks with different configurations which were burned in a controlled environment. Model vehicles having a square base were built according to the wood crib theory. The impact of varying longitudinal ventilation velocity and the cross-sectio...
An Experimental and numerical study on the combustion characteristics of pool fires in tunnels
Shafee, Sina; Yozgatlıgil, Ahmet; Department of Mechanical Engineering (2017)
This work presents the results of experimental and numerical analysis on tunnel fires in an attempt to improve existing knowledge on the fire dynamics and related safety measures in various tunnel fire scenarios. Results are grouped into four parts in which the effects of tunnel wall coating, inclination, tunnel obstruction and existence of secondary fire source in close vicinity were investigated on tunnel fire characteristics. A 1/13 longitudinally ventilated scaled tunnel model constructed based on Froud...
Experimental Investigation on the Mass Loss Rates of Thin-Layered n-Heptane Pool Fires in Longitudinally Ventilated Reduced Scale Tunnel
Shafee, Sina; Yamali, Uluc; Yozgatlıgil, Ahmet (2017-01-01)
Thin-layered n-heptane pool fires are burned with varied pool depths under longitudinal ventilation velocities ranging between 0.5-2.5 m/s in a reduced scale tunnel model. The combined effects of ventilation, pool size, and depth are investigated on the heat release rate, temperature distribution, and mass loss rate of fire. The gas temperature distribution and heat release rate results indicate that the critical ventilation velocity is achieved around 1 m/s in the scaled model, corresponding to 3.6 m/s in ...
An analysis of tunnel fire characteristics under the effects of vehicular blockage and tunnel inclination
SHAFEE, SINA; Yozgatlıgil, Ahmet (Elsevier BV, 2018-09-01)
It is known that the blockage and inclination conditions of tunnels are among the important factors affecting fire safety considerations, as these factors could change the characteristics of possible fire incidents as well as smoke movement in tunnels. In the present work, we analyze the variations of the tunnel fire burning rate, heat release rate and smoke backlayering as being functions of these two factors. Ethanol pools were used as fire sources in a reduced scale tunnel model with longitudinal ventila...
Modeling the effect of dose rate and time on crosslinking and scission in irradiated polyethylene
Sargın, Irmak; Beckman, S. P. (2020-06-01)
The insulation around the electrical cabling in nuclear power plants is frequently made of ethylene-propylene rubber and crosslinked polyethylene that is subjected to low levels of environmental stressors and radiation over the duration of their decades long service life. For the purpose of maintenance and reactor recertification, it is necessary to develop a non-destructive approach to determine the degree of damage the insulation has sustained. Accelerated aging experiments are used to develop these metho...
Citation Formats
S. SHAFEE and A. Yozgatlıgil, “An experimental study on the burning rates of interacting fires in tunnels,” FIRE SAFETY JOURNAL, pp. 115–123, 2018, Accessed: 00, 2020. [Online]. Available: