Drag-reducing agents are additives in pipelines that reduce turbulence in a pipe. Usually used in petroleum pipelines, they increase the pipeline capacity by reducing turbulence and therefore allowing the oil to flow more efficiently. These agents are made out of high molecular weight polymers or micellar systems. The polymers help with drag reduction by decreasing turbulence in the oil lines. This allows for oil to be pumped through at lower pressures, saving energy and money.
Using just a few parts per million of the drag reducer helps to reduce the turbulence inside the pipe. Because the oil pushes up against the inside wall of the pipe, the pipe pushes the oil back down causing a swirling of turbulence to occur. When the polymer is added, it interacts with the oil and the wall to help reduce the contact of the oil with the wall. Knowing what will create the ideal drag reducer is key in this process.
Ideal molecules have a high molecular weight, shear degradation resistance, are quick to dissolve in whatever is in the pipe, and have low degradation in heat, light, chemicals, and biological areas.