A simplified experimental approach for measuring viscosity for water-in-crude-oil emulsions under flowing conditions

A method for calculating viscosity from measurements in a rotating wheel has been developed. The model is based on experiments with liquids with known viscosities at given temperatures. Input values are measured torque and velocity from the wheel. In addition, volume and density values for gas and liquid are necessary for calculating the viscosity values. Viscosities can be calculated with an accuracy of + 50/-30% within the velocity range 0.7-3 m/s and the viscosity range of 10-200 mPas. High temperatures and pressures can be applied in the wheel. The flow in the wheel resembles that in a pipeline. Hence, the wheel with the viscosity calculation model constitutes a powerful tool for evaluation of the flow properties of various liquids and liquid mixtures, including emulsions. The match in relative viscosity (viscosity relative to that of the pure continuous phase in an emulsion) is better than the match in absolute viscosity. This implies that the best area of application is for dispersions with a continuous phase of known viscosity. The method has proven to be of great help for the dimensioning of pipelines for oilfields tinder development.