Combustor, worked examples

Columbus, Ohio incident, 10, 158-159 Combining. See Mixing Combustion with air, screening methods, intentional chemistry, 40-il Combustor, worked examples, 120,122-124, 125... 

Water-reactive materials, screening methods, 47,49-50, 51 Worked examples, 119-134 combustor, 120, 122-124,125 intentional chemistry, 119-120,121 mixing, 128,130-132 oxygen system, 133-134 physical processing, 128,129 repackaging, 124,126-127... 

The heat is available at 1200 K, but there will be temperature differences in the heat exchanger, so more available work will be lost in the heat exchange process. What can we learn from this example If we examine the Carnot factor, the answer seems to be clear. If we increase the operating temperature of the combustor, we can increase the efficiency and lose less work in the process. For example, if we had chosen an operating temperature of 2000 K, as could be possible in the suspended bed, we would have obtained an efficiency of 0.79, which is quite considerable. However, any gain in efficiency could be offset by the increase in work necessary to pulverize the coal For the sake of simplicity, we have not included these in this analysis. From the point of view of efficiency of combustion,... 

We can make an estimate of the efficiency of a power plant using a gas turbine (see Figure 9.10). We assume that the combustor inlet temperature of the gases is T2 = 298.15 K and turbine inlet temperature of T3 = 1423.15 K and use the data from the methane combustion example. We further assume that the turbine has a total efficiency of 0.75. We will first compute the turbine work if the expansion is isentropic to 1 bar. Consider Equation 9.9, where we set AS = 0. We can derive the following [10] ... 

A common method of producing mechanical work (usually for electrical power gene-ration) is to use a gas turbine and the Brayton or gas turbine power cycles. This open cycle consists of a compressor (on the same shaft as the turbine), a combustor in which fuel is added and ignited to heat the gas, and a turbine that extracts work from the high-temperature, high-pressure gas, which is then exhausted to the atmosphere. The open-cycle gas turbine is used, for example, in airplane jet engines and in some trucks. This cycle is shown in Fig. 5.2-87 -... 

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