The objective of this study was to investigate the rheological
properties of the light crude oil and its emulsions in order to obtain more
knowledge about the rheological behavior of oil flow in pipelines. The
experiments were carried out at a temperature of 20^oC by using the RS600
RheoStress (ThermoHaake, Germany). The results showed that the viscosity of
the prepared emulsions varied with their water contents. In the case of
100% light crude oil, the study of the functional relationship demonstrated
the quasi-Newtonian behavior with a moderate constant viscosity. However,
for emulsions with different water concentrations, their rheological
behaviors were described in better way by the Ostwald de Waele and the
Herschel-Bulkley models. The stability of emulsions was identified by
measuring the rheological properties including non-Newtonian viscosity, the
elastic modulus, (G'), the loss modulus, (G''), the phase angle (@d) and
the complex viscosity (@h^*). The results indicated that the rheological
properties and the physical stability of emulsions were significantly
influenced by the water contents and the nature of crude oils.
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