467827 On the Role of Viscosity Variation on the Onset of Natural Convection
The obtained scaling relations show that the onset of instabilities is accelerated as the concentration and temperature dependency of heavy oil viscosity is enlarged. Moreover, it is observed that temperature dependency of viscosity has a greater effect on the onset of instabilities than its concentration dependency. However, the presence of solvents is crucial for occurrence of natural convection and they can lead to increased heavy oil production. The results of LSA are compared to the numerical simulation results and good agreement is obtained.
The proposed method provides a more realistic analysis of the problem since it considers transient nature for temperature and concentration fields and also includes the variation of heavy oil viscosity. The introduced scaling relations have a general form and they can be used to predict the onset and wavelength of instabilities under different conditions. Furthermore, the predicted wavelength of instabilities facilitates selection of the proper grid size in numerical simulation of solvent and steam recovery processes.