SUMMARY
In the petroleum, food and energy industry, non-Newtonian fluids are widely used and their transport in pipelines can be highly expensive. When designing such systems, predicting the pressure drop for a given flow rate is of primary importance. In this paper, the friction factor in straight pipelines is studied experimentally and by means of Computational Fluid Dynamics (CFD) techniques in the case of power-law and the Bingham plastic fluids. First, the accuracy of the CFD technique is demonstrated in the case of water. Then, a power-law fluid (Carbopol 971 solution) is examined experimentally and numerically and it is confirmed that by introducing the modified Reynolds number given in [1], the classic friction factor formulae can be used. In the case of the Bingham plastic fluids, CFD simulations were performed and friction factor curves for several Hedström numbers are reported which were found to be consistent with the corresponding literature.