Study on Mixing Characteristics of the Heavy Oil and the Light Oil Based on Experiment and Numerical Simulation

Adding the high condensate point heavy oil to low-temperature light oil forms gelled crude oil, which brings a new challenge for pipeline mixing flow assurance. This study utilizes a lab-scale stirring tank to conduct the mixing experiments of the heavy oil and light oil under different temperature conditions for investigating the relationship between the temperature difference and the formed mass of the gelled oil. Meanwhile, numerical simulation is used to study the mixing characteristics of heavy oil and light oil. The experimental results demonstrate that the formed masses of the gelled oil decrease with the temperature difference decreasing. When the values of temperature difference are 4 and 0 °C, the flow ability of the mixing oils enhances and the formed masses of the gelled oil are almost negligible, which are 0.74 and 1.67 g for both different properties of heavy oils. Furthermore, the yield stress of the gelled oil decreases with the decrease in temperature difference. The simulation results exhibit that the velocity distribution shows a non-monotonic trend along the radial direction of the stirring paddle, with the maximum value occurring at the end region of the stirring paddle. In addition, the shear stress is 20% higher than the yield stress of the gelled oil consisted by crude oil A and crude oil C at the value of temperature difference is 10 °C, which explains well the experimental phenomenon of gelled oil disappearing.