Where the molecular weight of air, M a, is 28.967. Because c r = c g p pc,Ĭalculating the relative density (specific gravity)Ĭalculate the relative density (specific gravity) of natural gas with the following composition (all compositions are in mol%):įirst, calculate the apparent mole weight from the information presented in Table 1. 1-2 in Isothermal compressibility of gases for the previously calculated values of p r = 3.200 and T r = 1.500 to give c r T r = 0.5. The compressibility is determined by first reading Figs. The correction for 10% CO 2 is 0.0005 cp, and the correction for 7% H 2S is 0.0002 cp. The viscosity is determined using the charts of Carr et al. 2 in Gas formation volume factor and density: The formation volume factor is calculated from Eq. 3 in Gas formation volume factor and density:
4 Calculating the z factor for a reservoir fluidįind the density, formation volume factor (FVF), viscosity, and isothermal compressibility of a gas with the following properties and conditions:.2 Calculating the relative density (specific gravity).1 Calculating properties of natural gas.
