Effects of interlayer distance and cable spacing on flame characteristics and fire hazard of multilayer cables in utility tunnel

An, Weiguang; Wang, Tao; Liang, Kai Ming; Tang, Yanhua; Wang, Zhe

doi:10.1016/j.csite.2020.100784

Cited by 43 publications

(13 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to the prediction of the reaction to fire class, the FIGRA parameter is an important characteristic for predicting the fire dynamics in areas where cables or synthesis polymers form a significant part of the fire load (e.g. cars, tunnels, and server rooms), further details are described in [11][12][13][14].…”

Section: Resultsmentioning

confidence: 99%

Fire Growth Rate Index as a Key Fire Characteristic of Electrical Cables

Martinka

Rantuch

Wachter

et al. 2021

Research Papers Faculty of Materials Science and Technology Slovak University of Technology

View full text Add to dashboard Cite

This study deals with the Fire Growth Rate Index (FIGRA) as a key fire characteristic of electrical cables (determined by a cone calorimeter) that allows to estimate their reaction to fire class. Three power (supply) electrical cables (reaction to fire class B2ca) were tested by a cone calorimeter using different heat fluxes of 20, 30, 40 a 50 kW·m−2. The cables were three-wire (cross-section of each wire was 1.5 mm2) with a nominal voltage of 0.6 kV (alternating current), resp. 1 kV (direct current). The cable sheaths were made of an ethylene copolymer filled with aluminum hydroxide. The beddings were made of an ethylene copolymer filled with a mixture of aluminum hydroxide and calcium carbonate. The conductor insulations of one electrical cable were made of crosslinked polyethylene and the conductor insulations of the other two electrical cables were made of an ethylene copolymer filled with aluminum hydroxide. FIGRA was determined per unit length and unit area of electrical cables. FIGRA increased with increasing heat flux. At a heat flux of 50 kW·m−2, all the electric cables examined showed a very similar FIGRA (from 0.19 to 0.21 kW·m−1·s−1 and 18.4 to 21.2 kW·m−1·s−1, respectively). Conversely, at a heat flux of 20 kW·m−2, the investigated cables showed greater FIGRA variance (in the range of 0.11 to 0.16 kW·m−1·s−1 or 10.8 to 16.2 kW·m−1·s−1).

show abstract

Section: Resultsmentioning

confidence: 99%

Fire Growth Rate Index as a Key Fire Characteristic of Electrical Cables

Martinka

Rantuch

Wachter

et al. 2021

Research Papers Faculty of Materials Science and Technology Slovak University of Technology

View full text Add to dashboard Cite

show abstract

“…The digital camera was produced by SONY (Tokyo, Japan). The performance parameters of these cameras are shown in Table 4 [16]. In order to make the infrared camera data more accurate and reliable, it is necessary to calibrate the emissivity for the measuring software of the infrared camera prior to use.…”

Section: Experimental Materials and Methodsmentioning

confidence: 99%

Effects of Overlap Length on Flammability and Fire Hazard of Vertical Polymethyl Methacrylate (PMMA) Plate Array

Wang

et al. 2020

Polymers

Self Cite

View full text Add to dashboard Cite

Polymethyl methacrylate (PMMA) plates are widely used in buildings or factories for natural lighting. Commonly PMMA plates are installed as a discrete array. However, PMMA plates are very susceptible to fire. Therefore, experimental study on flammability and fire hazard of vertical PMMA plate array with different overlap length (D) was conducted in this work. The average flame height (Hf) increases first and then decreases with an increase in the overlap length, and reaches the maximum when D = 40 mm. The discrete flame spread speed (Vf) also rises first and then drops with the increase of D, which is mainly due to the heat transfer from the PMMA flame to the next plate. A model for predicting the flame spread rate of discrete PMMA array is established. The predicted results are consistent with experimental ones, with a predicted error smaller than 15%. The average temperature of flame zone rises first and then drops as D increases, reaching the maximum when D = 40 mm. This leads to the same changing trend of radiative heat flux. Results obtained in this work provide a reference for fire hazard evaluation and fire safety design of PMMA plates employed in buildings or industrial sites.

show abstract

“…The work [5] presents the results of studies of the effect of the distance between cables and their layers on the height and width of the flame when burning cables laid in the tunnel. The paper also presents data on the speed of horizontal flame propagation along the cables.…”

Section: Literature Review and Problem Statementmentioning

confidence: 99%

Improvement of test methods and criteria for evaluation of resistance to flame propagation of long elements of the wiring system

Kravchenko

Illiuchenko

Onyshchuk

et al. 2021

EEJET

View full text Add to dashboard Cite

The test methods for flame propagation of long elements of the electrical wiring system, in particular, cables, cable conduits and ducts, are analyzed, and differences in them are found in the test conditions and criteria for evaluating the resistance to flame propagation. Using a substrate of a wooden board covered with a layer of tissue paper with an areal density of (21±9) g/m2, adopted for testing other elements of the electrical wiring system, a cable was identified that is not resistant to flame propagation. It is proposed to use this substrate for testing the flame propagation of cables instead of a substrate made of a double layer of filter paper with a surface density of (80±15) g/m2. In one of three experiments, a cable that was not resistant to flame propagation was found based on the criterion of the presence of ignition of the substrate located under it. To reduce the risk of making an incorrect decision on compliance, it is proposed that the assessment of long elements of the wiring system be carried out according to the rules established for cable ducts, trays and ladders in EN 50085-1 and IEC 61537. For the AVVG cable with an outer diameter of 10 mm to 60 mm, when it touches the blue flame cone of 1 kW, the correlation coefficient of the dependence of the length of the charred part on the diameter was 0.969. For a distance of 100 mm between the sample and the burner along its axis, a correlation coefficient of 0.985 was obtained. It is proposed to test cables under the second condition recommended in IEC 60695-11-2. For two conduits, flame propagation was revealed when exposed to a 1 kW flame for 120 s and 240 s. However, for these pipelines, flame propagation did not occur under standard conditions of exposure to such a flame for 20 s and 25 s. To identify long elements of the wiring system that are not resistant to flame propagation, it is proposed to test them at a duration of exposure to a flame of 1 kW, established for cables in IEC 60332-1-2

show abstract

Effects of interlayer distance and cable spacing on flame characteristics and fire hazard of multilayer cables in utility tunnel

Cited by 43 publications

References 23 publications

Fire Growth Rate Index as a Key Fire Characteristic of Electrical Cables

Fire Growth Rate Index as a Key Fire Characteristic of Electrical Cables

Effects of Overlap Length on Flammability and Fire Hazard of Vertical Polymethyl Methacrylate (PMMA) Plate Array

Improvement of test methods and criteria for evaluation of resistance to flame propagation of long elements of the wiring system

Contact Info

Product

Resources

About