Ratio of heat capacities

Ratio of heat capacities y Second virial coefficient B... 

The maximum compression ratio (ratio of outlet to inlet pressure) for compressors depends on the design of the machine, the properties of the lubricating oil used in the machine, the ratio of heat capacities of the gas(Cp/Cy = y), other properties of the gas (e.g. tendency to polymerize when heated), and the inlet temperature. The most common types of compressor used for gas compression in the process industries are ... 

FiN = inlet volumetric flowrate (m3-s 1) y = ratio of heat capacities Cp/Cy (—) rjis = isentropic efficiency (—)... 

Table 13.8 gives the ratio of heat capacities CP/CV for a number of common gases. 

The ratio of heat capacities for the mixture can be taken as a weighted mean of the values in Table 13.8. 

An ideal gas flows in steady state adiabatic flow along a horizontal pipe of inside diameter d, = 0.02 m. The pressure and density at a point are P = 20000 Pa and p = 200 kg/m3 respectively. The density drops from 200 kg/m3 to 100 kg/m3 in a 5 m length. Calculate the mass flux assuming that the Fanning friction factor /= 9.0 x 10 3 and the ratio of heat capacities at constant pressure and constant volume y = 1.40. 

A high temperature and pressure is rapidly attained in a shock heated gas, governed ideally by the pressure ratio across the shock front and the ratio of heat capacities of the gases [80-82]. The discontinuity means that a reactant gas is raised virtually discontinuously to the shocked gas temperature, Tq. The time interval available before a rapid cooling occurs, 10-1000 jLis, is kinetically significant at high temperatures. Heat losses are negligible over this reaction time interval. These are ideal circumstances in which quantitative kinetic measurements may be made. 

Y = ratio of heat capacities, here taken as 1.4 Ti = initial absolute temperature, equal to 300 K P2/P1 = overall pressure ratio, equal to 54.5... 

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