Prediction of the Kinematic Viscosity of Libyan Crude Oil as a Function of its Specific Gravity as One Input Data

The prediction of the kinematic viscosity of some Libyan crude oils based on its specific gravity as one input parameter has been investigated. The correlation was developed in order to improve on the accuracy of existing correlations and to assist oil kinematic viscosity where the knowledge of viscosity of uncharacterized crude oils is required. The data used to build the correlation consist of measurements from 4 crude oils from various locations around Libya, the range from 0.81 to 0.84 g/cm3, resulting in kinematic viscosity values ranging from 5 – 11 mm2/s. The correlation can be used as far as the specific gravities’ values are available. When a single specific gravity measurement is available at 15oC, it can predict the viscosity at 40 oC with an average absolute deviation (AAD) of 6.58%, which is an improvement in accuracy compared to previously published correlations (Puttagunta) with the kinematic viscosity at 37.8 as one input for kinematic viscosity prediction was 7.17%. Finally, when a t-test which is an inferential statistic used to determine if there is a significant difference between the means of experimental and theoretical data of kinematic viscosity, the difference was considered to be not statistically significant. It is worth noting that the required input for this equation is only the specific gravity.