Predicting the Viscosity of Natural Gas

The viscosity of natural gas has been evaluated by four methods: the Lohrentz Bray Clark (LBC), Pedersen et al. (PFCT), SUPERTRAPP, and Vesovic Wakeham (VW) methods. The predictions have been compared with available experimental data that cover the temperature range from 240 to 444 K and pressures up to 55 MPa. The PFCT and VW methods showed the smallest rms deviations, while the predictions of SUPERTRAPP were only marginally worse. The results indicate that these three methods are capable of predicting the viscosity of natural gas with an rms deviation of 30 and maximum deviations of 5 to 60. The LBC method proved less reliable with maximum deviations of 8 to 90.