Composition of combustion product

Several techniques are available in the literature for evaluation of the flame temperature, exit temperature, equilibrium composition of combustion products, and performance parameters of energetic composites [11-13]. The optimum combination of the composite ingredients is determined by thermodynamic means, so as to arrive at a composition having maximum performance... 

A large portion of combustion products from industrial and utility operations is regarded as waste, which is directly disposed of in surface impoundments and landfills. The interest in the chemical composition of combustion products... 

The mixture ratio R is a volume concentration of index fuel (CO + H2) relative to the sum of index and limit fuels, where the limit fuel is CO + CH4 or H2 + CH4. Mixtures having the same value of MN yield the same composition of combustion products and adiabatic flame temperature when burning stoichio-metrically with air. This choice was made in order to assess whether adiabatic flame temperature and final composition were significant factors in explaining differences of behavior for different fuel compositions. Additional details on the selection of gas mixtures composition can be found in Reference (9). 

The frozen performance is based on the assumption that the composition of combustion products remains constant ( frozen ), while equilibrium performance is based on the assumption of instantaneous chemical equilibrium during the expansion in the nozzle. 

Determination of Combustion Temperature and Equilibrium Composition of Combustion Products... 

Figure 5.2 Aluminum-oxygen combustion at (a) 1 and (b) lObar. Adiabatic flame temperature and main composition of combustion products.

Amourttofthe aluminum (mol) Phase composition of combustion products... 

From a practical point of view, it is important to know the composition of combustion products, i.e., the chemical equation that describes the transformation of the explosive into its final products. This in turn enables the calculation of the thermochemical parameters of the combustion process and the estimation of some other parameters that can be related to the explosive strength. 

The Chapman-Jongnet (CJ) theory is a one-dimensional model that treats the detonation shock wave as a discontinnity with infinite reaction rate. The conservation equations for mass, momentum, and energy across the one-dimensional wave gives a unique solution for the detonation velocity (CJ velocity) and the state of combustion products immediately behind the detonation wave. Based on the CJ theory it is possible to calculate detonation velocity, detonation pressure, etc. if the gas mixtnre composition is known. The CJ theory does not require any information about the chemical reaction rate (i.e., chemical kinetics). 

When one considers the potential high-energy release on rupture of a carborane unit, together with the thermodynamic stability of combustion products, it is hardly surprising that there is a body of literature that reports on the use of carbo-ranes within propellant compositions. Their use in energetic applications is to be expected when the enthalpy of formation (AH/) data for the products of combustion for boron are compared to those of carbon. Thermodynamic data for the enthalpy of formation of o-carborane and of typical boron and carbon combustion products is shown in Table 4. Measurements of the standard enthalpy of combustion32 for crystalline samples of ortho-carborane show that complete combustion is a highly exothermic reaction, AH = — 8994 KJmol. ... 

The goal of the present study is to provide the information needed for design of a practical underwater propulsion system utilizing powdered aluminum burned with steam. Experiments are being conducted in atmospheric pressure dump combustors using argon/oxygen mixtures and steam as oxidizers. Spectrometer measurements have been made to estimate combustion temperatures and radiant heat transfer rates, and samples of combustion products have been collected to determine the composition and particle size distribution of the products. 

The flow involves fuel, F, issuing from a central slot of width D with an oxidizer, O, co-flow with both streams at the reference temperature, Tq. A global single-step, irreversible, exothermic chemical reaction of the type F + rO —> (1 -f r)P with an Arrhenius reaction rate coefiicient is assumed. A hot layer of combustion products, P, at the inlet serves to separate the fuel and oxidizer streams and acts as an ignition source. The inlet conditions for the velocity, temperature, and composition are shown in Fig. 10.2. The ratio of the inlet velocities of the fuel to oxidizer streams is chosen as 4. Inlet velocity forcing is used to induce early roll-up and pairing of the jet shear layer vortices. 

Fig.4.17 Specific impulse, adiabatic flame temperature, and molecular mass of combustion products for HMX-GAP composite propellants.

Fig. 4.18 Mole fractions of combustion products from HMX-GAP composite propellants.

Study of the composition of combustion or explosion products. With rapid scan spectro-... 

After 20 sec the powder had burnt completely and fresh air was introduced into the container. The hot combustion products exploded again on being mixed with air. The estimated composition of the products after the second explosion... 

Naiborodenko, Y. S., and Itin, V. I., Gasless combustion of mixtures of metal powders. II Effect of mixture composition of the combustion rate and the phase composition of the products. Combust. Explos. Shock Waves, 11,626 (1975b). 

Given a combustion reactor and information about the fuel composition, calculate the feed rate of air from a given percent excess or vice versa. Given additional information about the conversion of the fuel and the absence or presence of CO in the product gas, calculate the flow rate and composition of the product gas. 

As discussed in Chapter 7, polluted air varies in composition from locale to locale and with the time of day and meteorological conditions in a given locale. Polluted urban air contains oxides of sulfur and nitrogen, carbon monoxide, ozone, uncombusted and partially combusted hydrocarbons from gasoline and diesel vehicles, and particulate matter. PM 2.5 particulates, the standard for evaluating pollution related to cardiovascular disease, are composed of combustion products, airborne soil, sulfates, nitrates, and heavy metals as listed in Table 29.4.141-45 ... 

The complex dependency of the yield of combustion products on the ammonia partial pressure indicates that various factors are influencing the rate of formation of this product class. If ammonia is only inhibiting the adsorption of propene, then the yield of combustion products is expected to follow the same trend as the yield of the partial (amm)oxidation products. Ammonia is not only consumed for the formation of acrylonitrile, but can also reduce the surface under the formation of e g. N2. This will change the degree of reduction of the surface, and hence the composition of the pool of oxygen species. If ammonia cannot... 

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