Experimental determination of the evolution of the incident heat flux received by a combustible during a cone calorimeter test: Influence of the flame irradiance

2020 ◽  
pp. 073490412097044
Author(s):  
Fabien Hermouet ◽  
Éric Guillaume ◽  
Thomas Rogaume ◽  
Franck Richard ◽  
Mohamad El Houssami
Keyword(s):  
Heat Flux ◽  
Cone Calorimeter ◽  
Mass Loss Rate ◽  
Polymeric Materials ◽  
Acrylonitrile Butadiene Styrene ◽  
Analytical Treatment ◽  
Irradiance Level ◽  
Cone Calorimeter Test ◽  
The Matrix ◽  
The Impact

The decomposition kinetic of polymeric materials in a cone calorimeter strongly depends on the irradiance level imposed at the sample’s surface. Indeed, even if the irradiance level is supposed to be kept constant during cone calorimeter test, the amount of heat flux which is emitted by the flame can greatly increase the total heat flux received by the material. Analytical treatment on recently obtained results of an acrylonitrile-butadiene-styrene’s mass loss rate with controlled atmosphere cone calorimeter has shown that the differences observed between well-ventilated and inert environments can be attributed to the impact of the flame. This observation has brought the necessity to determine the impact of the flaming process on the material thermal decomposition. To do so, series of experiments have been devised, based on the insertion of a heat fluxmeter within the matrix of an acrylonitrile butadiene styrene material, during cone calorimeter tests in order to measure the flame heat flux as a function of the decomposition and the combustion processes.

Experimental study on fire behaviors of flexible photovoltaic panels using a cone calorimeter

2017 ◽  
Vol 36 (1) ◽  
pp. 63-77 ◽  
Author(s):  
Xiaoyu Ju ◽  
Xiaodong Zhou ◽  
Kun Zhao ◽  
Fei Peng ◽  
Lizhong Yang
Keyword(s):  
Heat Flux ◽  
Differential Scanning Calorimetry ◽  
Polyethylene Terephthalate ◽  
Cone Calorimeter ◽  
Mass Loss Rate ◽  
Ignition Time ◽  
Scanning Calorimetry ◽  
Photovoltaic Panel ◽  
Photovoltaic Panels ◽  
Fire Properties

Photovoltaic arrays are mounted on the surfaces of modern buildings to harness renewable energy. When a building catches fire, burning photovoltaic panels could worsen an already very hazardous environment. This work deals with the effect of building flame radiation on the fire behaviors of flexible photovoltaic panel installed in building-integrated photovoltaic systems. Cone calorimeter tests were conducted in air with a piloted ignition. The influence of heat flux on photovoltaic fire properties was studied. Several characteristic parameters are systematically determined or calculated, including ignition time, critical heat flux, mass loss rate, gasification heat, heat release rate, and effective heat of combustion. Thermogravimetry and differential scanning calorimetry test was conducted to identify the decomposition mechanism. The comparison of fire properties of photovoltaic and polyethylene terephthalate + tedlar-polyester-tedlar and thermogravimetry and differential scanning calorimetry analysis reveal that polyethylene terephthalate is the main component responsible for decomposition and burning of flexible photovoltaic panel.

scholarly journals Effects of External Heat Flux and Exhaust Flow Rate on CO and Soot Yields of Acrylic in a Cone Calorimeter

2021 ◽  
Vol 11 (13) ◽  
pp. 5942
Author(s):  
Sun-Yeo Mun ◽  
Jae-Ho Cho ◽  
Cheol-Hong Hwang
Keyword(s):  
Heat Flux ◽  
Mass Flow ◽  
Flow Rate ◽  
Cone Calorimeter ◽  
Mass Loss Rate ◽  
External Heat ◽  
Heat Fluxes ◽  
Temperature Fields ◽  
The Mean ◽  
External Heat Flux

The effects of changes in irradiance level (external heat flux), exhaust flow rate, and hood height on CO and soot yield were examined using a cone calorimeter. Black acrylic, having similar constituents as polymethyl methacrylate, was used as a combustible, and external heat fluxes ranging from 15 to 65 kW/m2 were considered. Both auto and spark ignitions were applied as ignition methods. The difference in auto and spark ignition methods had no effect on CO and soot yields, or on the mass loss rate (MLR), heat release rate (HRR), and effective heat of combustion (EHC), which are global parameters of fire. As the external heat flux increased, the mean MLR and HRR linearly increased while the EHC remained constant. When the external heat flux increased, the mean mass flow rates of CO and CO2 had a directly proportional relationship with the mean MLR. Consequently, CO and CO2 yields remained constant regardless of the external heat flux. In contrast, the mean mass flow rate and mean MLR of soot were linearly proportional as opposed to directly proportional, and the soot yield thus increased linearly with external heat flux. Variations in the exhaust flow rate and hood height, which can alter the velocity and temperature fields in post-flame and plume regions, had almost no impact on CO and soot yields, as well as on MLR and HRR. The results of this study are expected to provide improved insight into conventional approaches on the recognition of CO and soot yields as unique properties of each combustible.

Effect of the matrix plasticization behavior on mechanical properties of PVC/ABS blends

2017 ◽  
Vol 37 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Baijun Liu ◽  
Yinglin Wang ◽  
Yuan Gao ◽  
Rui Zhong ◽  
Fucai Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Acrylonitrile Butadiene Styrene ◽  
Dioctyl Phthalate ◽  
Operation Temperature ◽  
Brittle Ductile Transition ◽  
Transmission Electron ◽  
The Matrix ◽  
Tan Δ ◽  
The Impact

Abstract Acrylonitrile-butadiene-styrene (ABS) grafted copolymer prepared by emulsion polymerization was used to modify different molecular weight poly (vinyl chloride) (PVC) resins. The effects of the molecular weight of the PVC resins on dynamic mechanical analyses (DMA) of PVC/ABS blends and matrix plasticizing behavior on the impact mechanical properties and the morphology were investigated. The tan δ peaks of PVC/ABS blends occurred at the same temperature obtained by DMA, indicating that miscibility of PVC/ABS blends was independent of the molecular weight of PVC. The notched Izod impact test results indicated that the amount of polybutadiene (PB) rubber needed for the brittle-ductile transition (BDT) increases together with the molecular weight of PVC when milled at 165°C. Increasing the operation temperature and adding the plasticizer dioctyl phthalate (DOP) could change the matrix plasticizing extent and the BDT. At a milling temperature of 165°C, the BDT was reached only with 3.6 wt% PB when DOP was added, in contrast to the addition of 7.2 wt% PB in the absence of DOP. The morphology of different plasticized degree of PVC/ABS blends was studied by transmission electron microscopy (TEM) showing that the PVC-1/ABS blends milled at 165°C showed a larger unstained area than the other series of PVC blends.

scholarly journals The Effect of Graphene Oxide and SEBS-g-MAH Compatibilizer on Mechanical and Thermal Properties of Acrylonitrile-Butadiene-Styrene/Talc Composite

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3180
Author(s):  
Fatin Najwa Joynal Joynal Abedin ◽  
Hamidah Abdul Hamid ◽  
Abbas F. M. Alkarkhi ◽  
Salem S. Abu Amr ◽  
Nor Afifah Khalil ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Thermal Properties ◽  
Mechanical Stability ◽  
Flexural Modulus ◽  
Acrylonitrile Butadiene Styrene ◽  
Mechanical And Thermal Properties ◽  
Melt Mixing ◽  
The Matrix ◽  
The Impact ◽  
Butadiene Styrene

In this study, acrylonitrile butadiene styrene (ABS)/talc/graphene oxide/SEBS-g-MAH (ABS/Talc/GO/SEBS-g-MAH) and acrylonitrile butadiene styrene/graphene oxide/SEBS-g-MAH (ABS/GO/SEBS-g-MAH) composites were isolated with varying graphene oxide (0.5 to 2.0 phr) as a filler and SEBS-g-MAH as a compatibilizer (4 to 8 phr), with an ABS:talc ratio of 90:10 by percentage. The influences of graphene oxide and SEBS-g-MAH loading in ABS/talc composites were determined on the mechanical and thermal properties of the composites. It was found that the incorporation of talc reduces the stiffness of composites. The analyses of mechanical and thermal properties of composites revealed that the inclusion of graphene oxide as a filler and SEBS-g-MAH as a compatibilizer in the ABS polymer matrix significantly improved the mechanical and thermal properties. ABS/talc was prepared through melt mixing to study the fusion characteristic. The mechanical properties showed an increase of 30%, 15%, and 90% in tensile strength (TS), flexural strength (FS), and flexural modulus (FM), respectively. The impact strength (IS) resulted in comparable properties to ABS, and it was better than the ABS/talc composite due to the influence of talc in the composite that stiffens and reduces the extensibility of plastic. The incorporation of GO and SEBS-g-MA also shows a relatively higher thermal stability in both composites with and without talc. The finding of the present study reveals that the graphene oxide and SEBS-g-MAH could be utilized as a filler and a compatibilizer in ABS/talc composites to enhance the thermo-mechanical stability because of the superior interfacial adhesion between the matrix and filler.

scholarly journals Effect of the Cone Heater Scale Compliant with the ISO 5660 Standard on Spatial Uniformity of Radiant Heat Flux

2020 ◽  
Vol 34 (5) ◽  
pp. 27-33
Author(s):  
Sanghoon Ryu ◽  
Sun-Yeo Mun ◽  
Cheol-Hong Hwang
Keyword(s):  
Heat Flux ◽  
Heat Release ◽  
Cone Calorimeter ◽  
Large Deviation ◽  
Mass Loss Rate ◽  
Radiant Heat ◽  
Radiant Heat Flux ◽  
Spatial Uniformity ◽  
Measurement Results ◽  
Physical Quantities

Physical quantities such as mass loss rate, heat release rate, and total heat release are often measured through a cone calorimeter (a representative bench-scale apparatus) and are primarily considered as values per unit area. Hence, the uniformity of radiant heat flux supplied by the cone heater to the specimen is very important with respect to the measurement results’ validity. In this study, on the basis of the ISO 5660 standard, the uniformity of radiant heat flux at the specimen surface was evaluated for the cone heaters used with the cone calorimeter. It is observed that a normal cone heater (NCH) compliant with the ISO 5660-1 standard satisfies the requirement of uniformity within a range of ± 2% in the central 5 cm × 5 cm area, but it has a large deviation of approximately 13% at the position corresponding to the edge of the specimen. In addition, the duration of NCH usage does not significantly affect the distribution of radiant heat flux. Furthermore, it is observed that a large cone heater compliant with the ISO/TC 5660-4 standard can supply moderately-uniform radiant heat flux over the entire surface area (10 cm × 10 cm) of the specimen.

Study on the Micro Structure and Mechanical Properties of Nano-CaCO3/ABS Composites

2007 ◽  
Vol 121-123 ◽  
pp. 1459-1462 ◽  
Author(s):  
Wen Yi Wang ◽  
Guo Quan Wang ◽  
Xiao Fei Zeng ◽  
Ji Rui Song ◽  
Jian Feng Chen
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Acrylonitrile Butadiene Styrene ◽  
Mechanical Tests ◽  
Micro Structure ◽  
Bending Modulus ◽  
The Matrix ◽  
Abs Resin ◽  
The Impact ◽  
Fracture Section

The nano-CaCO3/Acrylonitrile-Butadiene-Styrene (ABS) composites were prepared by melting-blend with the single-screw extruder. The mechanical properties of the nanocomposites and the dispersion of nano-CaCO3 were investigated by means of transmission electron microscopy (TEM) and mechanical tests. The micro structure of the fracture section of the nanocomposites was analyzed by means of scanning electron microscopy (SEM). The results show that not only the impact property but also the rigidity property and the bending modulus of the system have been increased evidently by added modificated nano-CaCO3. However, the tensile strength of the nano-composites has a little decreased by added the modificated nano- CaCO3. The modificated nano-CaCO3 has been dispersed well in the matrix in the nanometer scale. The micro structure of the fracture section of the nanocomposites proved that when the composites have been impacted, the modificated nano-CaCO3 particles have taken an action of initiating and terminating crazing (silver streak), which can absorb more impact energy than the pure ABS resin. Compared with the pure ABS resin material, the notched impact strength of the nano-CaCO3/ABS composites added 2 percent hundred resin (PHR) modificated nano-CaCO3 reach 36.77 kJ/m2, which have been increased up to 44%. At the same time, the rigidity of the nanocomposites has also been enhanced by 23.5% which is increased from 28.16N to 34.87 N.

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