(144d) CFD Analysis of the Transient Flow in a Low-Oil Concentration Hydrocyclone

This work presents a multiphase flow analysis inside a DE-OILER hydrocyclone. This device is used to separate the residual oil (of order of 1000 ppm's) present in the water produced from the oil wells, after primary oil separation. The aim of the work is to develop a CFD model to analyze the flow pattern, pressure drop and separation efficiency of the device. One of the goals of the project is to run a CFD model for different operational conditions and use the information to design a control loop. Within this context, the transient behavior was analyzed in order to evaluate the characteristic times of the device, i.e., evaluate the necessary time to stabilize the hydrocyclone operation under changes in operational conditions. The SSG (Speziale, Sarkar, and Gatski (1991)) Reynolds Stress Model was used to compute the effects of turbulence, which uses a quadratic relation for the pressure-strain correlation and is known to properly predict the characteristic reverse flow in hydrocyclones. The Algebraic Slip Model was used to evaluate the separation efficiency. This approach for the dispersed oil flow allowed to consider a size distribution for the oil droplets at low computational cost.