Increasing the Flow Capacity and Reducing Drag in Microtubes Using Drag-Reducing Polymers

Decreasing pressure losses in microtubes is an important subject, especially when an increase in the flow capacity is required. In the same pumping power, decreasing the pressure drops coincides with increasing the fluid flow rate passing through a microtube. The current study aims to examine how the water pressure drop across a microtube can be affected by the addition of small concentrations of different drag-reducing polymeric agents. A kind of the laminarization behaviour was found by the addition of the selected polymer to the turbulent flow. The effect of the concentration of the drag-reducing agent (DRA) on the observed viscosity and drag values are reported. Moreover, the effects of different types of drag-reducing agents on the friction factor are obtained at the best concentration in the range of examined concentrations. Under this condition the percentage of the drag reduction and increase in the capacity of the flow were respectively 33 % and 36 %. The obtained results show that more drag reduction occurs at a higher flow rate for 20 ppm of the polyacrylamide with a high molecular weight.