Novel <i>k</i>-ω Turbulent Model for\nPrediction of Drag Reduction in Viscoelastic Fluid Flow

One effective method for reducing\npressure drop in turbulent\npipe\nflows is the injection of Drag Reducing Agents (DRA), a technique\nthat has been used for over 70 years. This study investigated the\nmodeling and simulation of turbulent pipe flow behavior by developing\na novel <i>k</i>-ω turbulence model and utilizing\nthe modified Generalized Newtonian Fluid (GNF) model to integrate\nthe fluid’s rheological properties. The focus was on turbulent\npipe flows involving DRA, which exhibit viscoelastic non-Newtonian\nfluid properties. This new <i>k</i>-ω model was derived\nfrom mathematical modeling by using the non-Newtonian <i>k</i>-ε model. Computational Fluid Dynamics (CFD) software was used\nto simulate the derived equations, incorporating non-Newtonian terms\nthat encompass the rheological properties of drag-reducing fluids.\nThese terms were implemented into the software using User-Defined\nFunctions (UDFs). To assess the accuracy of our results, we compared\nthem with data from the open literature, demonstrating a significant\nimprovement in the precision of our results. Our model exhibited good\nagreement with experimental data, with an average deviation of 10.53%\nin the friction factor predicted for the studied fluids. Furthermore,\nthe model showed high accuracy in near-wall regions, particularly\nthe viscous and buffer sublayers.