Combustion behavior

Diesel Fuel Characteristics Imposed by its Combustion Behavior... 

W. Langlotz, "Combustion Behavior of Classical PropeUants," in Fifth International Gun Propellant and Propulsion Symposium, ARDEC, Dover, N.J., Nov. 1991. 

Whereas there is no universally accepted specification for marketed natural gas, standards addressed in the United States are Hsted in Table 6 (8). In addition to these specifications, the combustion behavior of natural gases is frequently characteri2ed by several parameters that aid in assessing the influence of compositional variations on the performance of a gas burner or burner configuration. The parameters of flash-back and blow-off limits help to define the operational limits of a burner with respect to flow rates. The yeUow-tip index helps to define the conditions under which components of the natural gas do not undergo complete combustion, and the characteristic blue flame of natural gas burners begins to show yellow at the flame tip. These... 

Briquettes bum similarly to bituminous coal, although some tend to disintegrate on combustion. Alow (<6-7%) ash content increases the possibility of disintegration. Normal combustion depletes the combined oxygen and volatile matter in the coal quiddy, effectively changing its composition and combustion behavior, making control of combustion difficult. 

Combustion behavior differed in some respects between continuous and instantaneous spills, and also between LNG and refrigerated liquid propane. For continuous spills, a short period of premixed burning occurred immediately after ignition. This was characterized by a weakly luminous flame, and was followed by combustion of the fuel-rich portions of the plume, which burned with a rather low, bright yellow flame. Hame height increased markedly as soon as the fire burned back to the liquid pool at the spill point, and assumed the tilted, cylindrical shape that is characteristic of a pool fire. 

Radiation effects, as well as combustion behavior, were measured. LNG and refrigerated liquid propane cloud fires exhibited similar surface emissive power values of about 173 kW/m. ... 

One extremely important point to realize is that different propellant types may have different rate-controlling processes. For example, the true double-base propellants are mixed on a molecular scale, since both fuel and oxidizing species occur on the same molecule. The mixing of ingredients and their decomposition products has already occurred and can therefore be neglected in any analysis. On the other hand, composite and composite modified-double-base propellants are not mixed to this degree, and hence mixing processes may be important in the analysis of their combustion behavior. 

Takahashi, K., Muroya, M., Kondo, K., Hasegawa, T., Kikuchi, I., and Kawakami, M., Post Combustion Behavior in In-Bath Type Smelting Reduction Furnace, AS /./ Ini., 32 102 (1992)... 

Combustion behavior varies widely and is dependent on a wide range of parameters. 

Experiments were carried out in a spray combustion facility that can simulate the combustion behavior of many practical combustion systems. The facility... 

The calibrations obtained are valid over a significant range of each property. It is feasible to predict all these properties from the LTA from a small sample of coal, should that be desired. These results mainly show that the methods employed can model other ash properties which are more closely related to large-scale combustion behavior. This is one area where further study is desirable. 

Koch, E.-C., Metal-Fluorocarbon Pyrolants IV Thermochemical and Combustion Behavior of Magnesium/Teflon/ Viton (MTV), Propellants, Explosives, Pyrotechnics, Vol. 27, 2002, pp. 340-351. 

Computational and experimental methods clearly benefit from a symbiotic relationship in combustion studies. Theoretical calculations can propose important pathways to yield empirically observed intermediates by providing reaction energies and rate coefficients of elementary reactions, thereby guiding experiments. Moreover, theoretical calculations can potentially fill some gaps caused by limitations in experimental approaches the vast majority of analytical techniques fail to distinguish between structural isomers and to identify short-lived intermediate species, both of which are important objectives in delineating overall combustion behavior. Finally, modeling can identify species to look for experimentally. 

These compounds exhibit very low pressure-dependence during combustion and the compound [3,6-bis(nitroguanyl)-l,2,4,5-tetrazine] in particular, shows the lowest pressure exponent known in the literature for a neat material. Further, the interesting combustion behavior of these explosives make them suitable for gasgenerating and propellant applications [288]. 

The combustion behavior of Alex was also studied in gun propellants (up to high pressure =280 M Pa) and it was observed that the burn rate is nearly doubled compared with high-calorie conventional DB propellants [118]. Simultaneously, n decreases from >0.8 to 0.66. 

K. Kishore, Combustion Behavior of Some Cross-Linked Synthetic Resins , ColloidPolym-Sci 255 (2), 180-81 (1977) CA 86,107303 (1977) 8) K. Bitter, Igniters for Coal ,... 

These studies provide comprehensive information on the effects of many halogen compounds on the combustion behavior of various hydrocarbons. The combustion behavior included preflame oxidation, ignition over a wide range of temperature, and the flame process. The effect of iodine compounds on preflame combustion, which had not been previously investigated, is now reported. 

Work is being conducted presently at BCR to relate petrographic characteristics to coal combustion performance. Preliminary results of the study, although incomplete, show a reasonable correlation between certain petrographic properties and coal combustion behavior. 

Several approaches are being taken in an attempt to relate petrographic composition with combustion behavior. Figure 17 shows how R. along with FS1 and ash fusion data may be used to predict the burning rate of coals in a specific combustion type (cross-feed stoker). In general, as R and FSI increase and ash fusion temperatures decrease, coals require more grate surface to insure optimum burn-out and minimum loss of combustibles in the ash. 

This investigation shows that the average reflectance of vitrinite in coal (Ro) can be used to estimate carbonization product yields, by-product gas properties, chemical properties, oxidation effects, and combustion behavior. Moreover, R along with calorific value and volatile matter content might be employed to classify accurately and consistently coals of all ranks. 

In order to further investigate the effect of carbon content on the combustion behavior of titanium carbon mixtures, a series of experiments was performed in 1.4 MPa of argon gas. Figure 11.11 shows the variation... 

Shao, C. H., Huang, J. J., Chen, G. N., Yeh, J. T., and Chen, K. N., Thermal and combustion behaviors of aqueous-based polyurethane system with phosphorus and nitrogen containing curing agent, Polym. Degrad. Stab., 1999, 65, 359-371. 

The effects of metal-containing POSS on the combustion behavior of polypropylene have been investigated.46 Metal-POSS was prepared from incompletely condensed structures by reaction with organometallic compounds. The dimeric and oligomeric of Al and Zn-isobutyl silsesquiox-ane (POSS) have been evaluated as potential flame retardants for polypropylene, and the results were compared with PP/octaisobutyl POSS. The cone calorimeter data (Table 8.2) revealed that... 

The degradation and combustion behavior of polycarbonate/POSS hybrid system has been reported recently.48 Different loading contents of trisilanolphenyl-POSS (TPOSS) were melt blended with polycarbonate matrix (PC). The data shown in Table 8.4 indicate that no improvement in thermal stability parameters (i.e., onset decomposition temperature and peak decomposition temperature) was observed compared to the neat polycarbonate. The thermo-oxidative degradation process of the hybrid system proved to be a complicated process, which includes hydrolysis/alcoholysis of the carbonate linkage, free radical oxidative chain degradation, reformation, and branching and cross-linking reactions. 

The impact of the nanocomposite technology on polymers is huge, reflected in enhanced properties of the resulting PNs, such as enhanced mechanical, barrier, solvent-resistant, and ablation properties.12 The effect of nanocomposite technology on the thermal and fire performance of the polymers is primarily observed in two important parameters of the polymers (1) the onset temperature (7( ,nsct) in the thermogravimetric analysis (TGA) curve—representative of the thermal stability of the polymer, and (2) the peak heat release rate (peak HRR) in cone calorimetric analysis (CCA)—a reflection of the combustion behavior (the flammability) of the polymer. The Tonset will be increased and the peak HRR will be reduced for a variety of polymers when nanoscale dispersion of the nanoadditive is achieved in the polymer matrix. 

The impact of nanocomposite technology on flame retardance (the thermal and fire resistance) of the polymers, as mentioned in Section 11.1, is primarily reflected in two important parameters (1) the ronset in the TGA curve—representative of the thermal stability of the polymer and (2) the peak HRR in the curve of CCA—reflection of the combustion behavior (the flammability) of the... 

CBHF California Bureau of Home Furnishings and Thermal Insulation CBUF Combustion Behavior of Upholstered Furniture EC Research Project CEN European Committee for Standardization... 

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