Standard combustion chamber

Norm-Brennkammer = standard combustion chamber 60 Novit = mixture of hexanitrodiphenyl-amine, TNT and aluminum (Swedish) nozzle 239... 

Standard combustion chambers and laboratory combustion chambers ) have been developed for testing the behavior of solid rocket fuels and for the determination of their characteristic properties. 

Here, we first discuss whether such semi-closure (which is introduced so that CO2 separation can be undertaken more easily) is likely to lead to higher or lower thermal efficiency, and in this discussion it is helpful to consider recirculation in relation to an air standard cycle (see Fig. 8.4). Fig. 8.4a shows a closed air standard cycle with unit air flow Fig. 8.4b shows an open cycle similarly with unit air flow and an air heater rather than a combustion chamber. The cycles are identical in every respect except that in the former the turbine exhaust air from the turbine is cooled before it re-enters the compressor. In the latter, the turbine exhaust air is discharged to atmosphere and a fresh charge of air is taken in by the compressor. The quantities of heat supplied and the work output are the same for each of the two cycles, so that the thermal efficiencies are identical. 

The Oxidair Model EH thermal oxidizer is a horizontal forced-draft flume thermal oxidizer for destroying hydrocarbon vapors. The standard unit consists of a burner, combustion chamber, exhaust stack, pipe trains for auxiliary fuel and fume stream, draft air fan, and controls. 

There are several approaches available to a utility to construct a boiler that will meet New Source Performance Standards. These approaches can be classified according to the position in the combustion system at which pollutant control technology is applied. Precombustion control involves removal of sulfur, nitrogen, and ash compounds from the fuel before it is burned. For coal combustion this approach involves the application of coal-cleaning technology. Combustion control relies on modifications to the combustion process itself or the addition of material to the combustion process to reduce pollutant formation or capture the pollutants formed in the combustion chamber. Examples of combustion control include staged combustion, boiler limestone injection, and fluidized-bed combustion with limestone addition. Post-combustion control involves removal of pollutants after they have been formed but before they are released into the atmosphere. Traditionally, flue gas desulfurization has meant the application of postcombustion control either alone or in conjunction with another... 

Figure IV. A. 3. is a heat of combustion plot of the elements with fluorine as the oxidizer. One can carry through the same arguments as those made for the oxygen plot except it is well to remember that many of the metal fluorides are gaseous under the combustion chamber conditions that prevail. Since BF is a gas, the significance of boron compounds as fuels with fluorine oxidizers particularly changes for the better. Comparison of figures IV. A. 1. and IV. A. 3. will show that H2 -02 and H2 - F2 have the same standard state heat release. Yet above it was stated that the specific impulse with hydrogen-fluorine was the greater. This comparison again points out the limitations of the plots, which do not take into account the diss-...

The prediction of rocket propellant specific impulse, as well as impulse under other conditions, may be reliably accomplished by calculation using as input the chemical composition, the heat of formation, and the density of the component propellant chemicals. Not only impulse but also the composition of exhaust species (and of species in the combustion chamber and the throat) may be calculated if the thermodynamic properties of the chemical species involved are known or can be estimated. The present standard computer code for such calculations is that described by Gordon and McBride.44 Theoretical performance predictions using such programs are widely used to guide propellant formulation efforts and to predict rocket propellant performance however, verification of actual performance is necessary. 

The value for the specific impulse is high if the reaction heat is high and produces a high flame temperature, and if the average molecular weight of the reaction products is low. Data concerning specific impulses are only comparable if they refer to the same working pressure in the combustion chamber a frequently employed standard value is 1000 Ibs/sq. in. approx. 70 bar in test chambers. 

Table 8.2 shows typical levels of physical viscosity, turbulent viscosity i/t and artificial viscosity i/a reached in a combustion chamber for a standard regime. All viscosities are scaled by the physical viscosity. Note that viscosity affects all scales and not only the small scales. For example, acoustic waves are very strongly dissipated in a RANS code because the turbulent viscosity acts on them too. This is a collateral effect of turbulence models formulated using turbulent viscosities but it implies that such methods cannot be used for the present objectives. 

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