Study On The Structural Destructing Characteristic Of GNPOC Gelled Crude Oil

The influence of selecting a restart shear rate when doing a constant shear rate experiment using Physica MCR301 rheometer was first discussed in this paper. Point out that there is a certain applicable scope when doing a constant shear rate experiment using Physica MCR301 rheometer. To GNPOC crude oil, the restart shear rate should not be higher then 2 s^-1 nearby the freezing point.And then, influence factors of structural strength and structural destructing characteristic of GNPOC gelled crude oil which has certain heat history and shear history are studied. Temperature, pre-shear rate, cooling rate and temperature drop which influent the gelled strength are analyzed. Point out that by changing the microstructure of the gelled crude oil, the oil temperature, pre-shear rate, cooling rate and temperature drop have a great influence on the structural strength of the gelled crude oil.Different restart temperature, temperature drop and restart shear rate are analyzed based on a large number of experiments, and the destructing process can be divide into four stages: linear deformation, creep, plastic deformation, destruction. A constitutive equation is derived to describe the relationship between stress and strain during the initial structural destructing process of gelled crud oil under a constant shear rate. And fit the equation with the experimental data, find that the constitutive equation can describe the structural destructing process of the GNPOC crude oil very well.