Combustion Behavior (combustion + behavior)

Distribution by Scientific Domains


Selected Abstracts


Development of a Characterization Method for the Combustion Behavior of Solid Recovered Fuels

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2004
O. Kock
Apart from coal, fuels like solid biogenic or recovered fuels will gain increasing importance in power generation plants because of their potential to lower CO2 emissions. In order to produce a constant fuel quality and to guarantee a safe power plant operation, it is rather important to know the combustion behavior of the different fuel types. A characterization method is proposed by which the combustion behavior of solid fuels can be analyzed with low-cost equipment and reliable results. [source]


Combustion behavior of a falling sodium droplet: Burning rate-constant and drag coefficient

HEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 7 2005
Atsushi Makino
Abstract The combustion behavior of a single sodium droplet has been studied experimentally, by use of a falling droplet. It was found that D2 -law can hold for the sodium droplet combustion after the ignition, which can be observed to occur through an increase in the droplet temperature under a condition without a gaseous flame, suggesting that a surface reaction plays an important role in the ignition of sodium. It was also found that the burning rate-constant without forced convection has nearly the same value as those for conventional hydrocarbon droplets, although it is considered that the sodium combustion proceeds in an oxidizer-rich environment even in the air. This can be judged by comparing a temporal variation of the flame/droplet diameter ratio for the sodium droplet with that for the hydrocarbon droplet. A micro-explosion of the burning droplet is also observed when oxygen concentration in the ambience exceeds 0.33 in mass fraction. As for the falling velocity and/or distance of the burning droplet, it turned out that the use of the drag coefficient for solid sphere under isothermal condition is inappropriate in obtaining accurate values. It was also found in another experiment that when Re > 500, the drag coefficient of the falling droplet undergoing combustion is as high as 2 depending on combustion situation and/or droplet temperature, while that of the solid sphere under an isothermal condition is 0.44. © 2005 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(7): 481,495, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20084 [source]


Full-scale study on combustion characteristics of an upholstered chair under different boundary conditions,Part 1: Ignition at the seat center

FIRE AND MATERIALS, Issue 6 2009
Q. Y. Xie
Abstract The objective of this work is to investigate the effects of boundary conditions on the combustion characteristic of combustible items in a room. A series of full-scale experiments were carried out in the ISO 9705 fire test room with an upholstered chair at four typical locations, i.e. at the middle of side wall, at the center of the room with the seat toward the door, at the center of the room with the seat toward inside of the room, at the room corner, respectively. Ignition was achieved through a BS No.7 wooden crib at the geometric center of the seat surface for each test. Besides the heat release rate (HRR), four thermocouple trees were placed around the chair to monitor detailed temperature distributions during the combustion process of an upholstered chair. The results indicated that the boundary conditions had some effects on the combustion behavior of a chair in a room. It was shown that there were clearly two main peak HRRs for the cases of a chair being clung to the side wall or at the corner. However, there was only one main peak HRR when the chair was placed at the center of the room, either outwards or inwards. In addition, the results of the two cases of chairs being at the center indicate that the maximum HRR (about 829,kW) for the chair seat toward the door was relatively larger than the maximum HRR (about 641,kW) for the chair seat toward inside of the room. It was suggested that the special complex structure of a chair was also a considerable factor for the effect of boundary conditions on the combustion behavior of a chair in an enclosure. Furthermore, the measured temperature distributions around the chair also illustrated the effects of boundary condition on the combustion behavior of a chair in a room. It was suggested that although HRR was one of the most important fire parameters, HRR mainly represented the comprehensive fire behavior of a combustible item. In order to develop more suitable room fire dynamic models, more detailed information such as the surrounding temperature distributions measured by the thermocouple trees are useful. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Mechanical properties and flammability of polycarbonate alloys containing nanosize additives

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2009
Zhiyi Zhang
Abstract Different organic,inorganic composite particles [montmorillonite/poly(butyl acrylate) (PBA)/poly(methyl methacrylate) (PMMA), SiO2/PBA/PMMA, and CaCO3/PBA/PMMA] were synthesized by emulsion polymerization. Furthermore, polycarbonate (PC) alloys were prepared via the doping of these composite particles into PC with a twin-screw extruder. The structure, mechanical properties, and flammability of the PC alloys were studied in detail. Although the tensile modulus of PC decreased a little, the flexibility and impact resistance were improved by the addition of these composite particles. This result was attributed to the fact that the composite particles were well dispersed in the PC matrix, with a cocontinuous phase formed between the particles and PC. In addition, the combustion behavior of the PC alloys, compared with that of the pure PC, resulted from a ceramic-like char that formed on the surface of the PC alloys during burning. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source]


A new intumescent flame-retardant: preparation, surface modification, and its application in polypropylene

POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 8 2008
Xingyi Wang
Abstract Melamine salt of tripentaerythriol phosphate (MTP), as a new intumescent flame-retardant, was prepared from tripentaerythritol (TPE), polyphosphoric acid, phosphoric pentoxide, and melamine, and then incorporated into polypropylene (PP) to obtain flame-retarded PP-MTP. FT-IR analysis showed that MTP was in the form of cage structure. The flammability, combustion behavior, and thermal degradation and stability of flame-retarded PP were characterized by using LOI, UL-94 test, cone calorimetry, and TGA, respectively. By SEM, the char structure of PP-MTP was analyzed. XRD diffraction tests showed that PP-matrix of PP-MTP presented better crystallized phases, when MTP was modified by methyl hydrogen siloxane. The relations of the dispersion of MTP in PP matrix to the compatibility between PP and MTP, and to the flame retardancy were discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Conversion of Biomass Based Slurry in an Entrained Flow Gasifier

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2007
U. Santo
Abstract A two-step process, BIOLIQ, with pyrolysis and subsequent entrained flow gasification has been developed at the Forschungszentrum Karlsruhe to produce synfuel from biomass. Experiments in a 60,kW pilot-scale atmospheric entrained flow gasifier allow quantitative evaluation of the combustion behavior of biomass-based slurry, leading to a better understanding of the gasification process. [source]


Development of a Characterization Method for the Combustion Behavior of Solid Recovered Fuels

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2004
O. Kock
Apart from coal, fuels like solid biogenic or recovered fuels will gain increasing importance in power generation plants because of their potential to lower CO2 emissions. In order to produce a constant fuel quality and to guarantee a safe power plant operation, it is rather important to know the combustion behavior of the different fuel types. A characterization method is proposed by which the combustion behavior of solid fuels can be analyzed with low-cost equipment and reliable results. [source]