Methane heat capacity ratio

When actual data are not available, a useful approximate rule for ordinary temperatures and pressures, is to take y as 1.67 for monatomic gases, 1.40 for diatomic gases, 1.30 for simple polyatomic gases, such as water, carbon dioxide, ammonia and methane. It may be noted that the heat capacity ratio for hydrogen gas increases at low temperatures toward the vfdue for a monatomic gas. This matter will be explained in Chapter VI. 

Heat capacity ratio, k = Cp/c, = 1.04 for gases with molar mass > 100. The value of k increases to 1.67 as the molar mass decreases. For air =1.4 and for such gases as ethylene, carbon dioxide, steam, sulfur dioxide, methane, ammonia = 1.2-1.3. Temperature rise between feed 1 and exit 2 ... 

Heat capacity ratio, k, for methane 1.32 Heat of combustion for methane 50,000 kj/kg... 

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