Radiative properties of gases

In this section, we will give a short review for the radiative properties of gases and then present some easy-to-use formulations. 

Table A-2 Boiling and freezing point properties 843 Table A-3 Properties of solid metals 844 846 Table A-4 Properties of solid nonmetals 847 Table A-5 Properties of building materials 848-849 Table A-6 Properties of insulating materials 850 Table A-] Properties of common foods 851-852 Table A-8 Properties of miscellaneous materials 853 TableA-9 Properties of saturated water 854 Table A 10 Properties of saturated refrigerant-134a 855 Table A-11 Properties of saturated ammonia 856 Table A-12 "Properties of saturated propane 857 Table A-13 Properties of liquids 858 Table A-14 Properties of liquid metals 859 Table A- 5 Properties of air at 1 atm pressure 860 TableA-16 Properties of gases at 1 atm pressure 861-862 Table A-17 Properties of the atmosphere at high altitude 863 Table A-18 Emissivities of surfaces 864-865 Table A-19 Solar radiative properties of materials 866 Figure A-20 The Moody chart for friction factor for fully developed flow in circular pipes 867...

In this chapter, we presented a general overview of radiative heat transfer. A number of practical models were included for the solution of the radiative transfer equation and to calculate the required radiative properties of particles, combustion gases, and surfaces. Even though the material presented can allow the reader to tackle a radiative transfer problem, it is not possible to claim that our coverage of the subject was comprehensive. We tried to list most significant references, and the reader is encouraged to consult the literature for more detailed and the most up-to-date analyses and data. 

TABLE 1.7 Distribution and Selected Properties of Some Atmospheric Polluting Gases Having Absorption in the Radiative Window ... 

Skocypec and Buckius [180,181] presented an analytical formulation to obtain the radiation heat transfer from a mixture of combustion gases and scattering particles. They considered band models for the gases and accounted for the absorption and scattering by particles. They developed charts similar to Hottel charts for combustion gases. The results presented can be used to obtain the average radiative properties if the particle loading information is not known accurately. (See also Refs. 182-184 for a discussion on the limits of this formulation.)... 

In the first experiment, GHG, the concentrations of the following greenhouse gases were prescribed as a function of time CO, CH4, and N,0, as well as a series of industrial gases, including CFCs and HCFCs. The absorptive properties of each gas constituent were calculated separately. Furthermore, the radiative forcing was practically identical to the narrow band calculations. This meant an increase in the radiative forcing by some 10% compared to the actual broad band calculation in the radiation code of the model. 

The absorption bands of several trace gases overlap those of water drops and ice crystals. Because of the strong absorption properties of clouds, the infrared absorption by such trace gases is diminished in the presence of clouds. For example, calculations by Ramaswamy reported in IPCC (1995) show that the radiative forcing resulting from a 1 ppb increase in CFCI 3 in an overcast, midlatitude summer atmosphere with cloud top at 3 km is 37% less than the corresponding clear sky value (0.35 W m ). This reduction increases to 83% if the cloud top is at 10 km. 

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