Petroleum characterization from ultrasonic measurement

Ultrasonic speed measurements have been performed under pressure on three reservoir fluids highly dissimilar in both composition and nature in order to identify the most appropriate equation of state — mixing rule combinations for predicting thermophysical properties of these fluids and also in order to examine the influence of the number of cuts and the mode of grouping on speed of sound calculation. The comparative analysis which was carried out between the sound speed measurements and the values generated by models, has pointed out that the predictions provided by the Lee–Kesler model are very satisfactory including at the highest pressure investigated (120 MPa). Moreover, the comparative study reveals no systematic degradation in reducing the description of the composition to a limited number of cuts.