Application of the minimum transport velocity model for drag-reducing polymers

The objective of this work is to acquire further insight into the procedure for predicting the minimum fluid velocity, which is required to transport cuttings from a directional well. The minimum transport velocity model (MTV) was used for drag-reducing polymers such as xanthan gum (XG). A series of experiments to evaluate the predictions of the model were conducted using water, aqueous solutions of polyanionic celluose (PAC) and xanthan gum (XG). The experiments conducted in a 4-m-long and 8-cm-diameter test section with recirculation facilities. The tests were carried out by measuring critical velocities, which are required to initiate the motion of sand bed particles. Four sand beds with different particle size ranges were used in the experiments. The model predictions were compared to the experimental results. The model predictions of critical velocity show satisfactory agreement with the measured data.