High Salinity Permittivity Models for Water Cut Sensing

In high salinity water cut measurements, it is observed that the measurement breaks down as a result of the conductivity signal swamping the capacitive signal. An accurate parameterizable model of high salinity permittivity is required for the development of downhole high salinity water cut meters that will operate in reservoir brine conditions in the 100 000 ppm to 200 000 ppm range. Theoretical models proposed by Stogryn Meissner and Wentz, and Somaraju and Trumpf are compared against high salinity data obtained by Peynman An effective temperature correction accounting for the influence of salinity-induced viscosity variations on permittivity is devised. This improves the fit to the real component of permittivity within the salinity range of interest: the Meissner and Wentz model provides the best fit. Subsequently, additional mechanisms need to be considered to account for the global mismatch between theory and experiment.