Current Viscosity Measurements of Crude Oils

Viscosity is an important characteristic of crude oil. The viscosity of crude oil is changing with temperature, pressure and chemical composition change. In analyzing the determination of crude oil viscosity operations it is usual to use only the temperature dependence of viscosity while influence of pressure is neglected. Therefore the principal objective of this work is to obtain exact model that can successfully predict this important fluid property covering a wide range of temperatures, pressures and taking the composition into consideration. Moreover in this research a mathematical model of changing the current viscosity of Egyptian crude oils with changing of temperature and pressure is determined. A total of 9 different oil API gravities ranging from 13.4 to 40.4 are tested. Viscosity is measured in the temperature range from 20 to 150 °C and pressure range from 14.7 to 132.3 psi. These measurements are determined by using the quartz process viscometer apparatus. The new model successfully predicts the experimental data with an average absolute relative error of less than 3 % and correlation coefficients (R2) up to 0.991.