CFD simulation of drag reduction in pipe flow by turbulence energy promoters

In oil and gas industry, transportation of crude oil from terminal to terminal is costing enormous amount of money in order to restore back the pressure, which is lost due to the inner surface friction of the pipeline, through pumping operation. In this study, a new method has been proposed to reduce the drag in pipe flow by installing energy promoter at the inner wall to change the turbulence structure in the flow. CFD simulation was used to study the drag reduction at various number and various heights of energy promoters. Mesh independency study was conducted to ensure the integrity of the result. ANSYS CFX was used to simulate the flow inside the pipeline with a section of energy promoter embedded at the inner wall. The pipeline with energy promoter is modelled using Solid works and imported to ANSYS CFX Fluid Flow to undergo simulation. With water as working fluid, the results obtained were compared with the empirical correlation results to ensure the validity of the simulation procedure. Results have demonstrated drag reduction in all cases of energy promoter's height, number, and flow rates. 1.0 mm height showed better drag reduction, and the 12 energy promoters installed on the internal surface of the pipe showed larger reduction in the drag compared to 8 and 4 promoters. The maximum drag reduction efficiency of energy promoter is approximately 7 and it is possible to further push the boundary for drag reduction efficiency limit. In summary, it is feasible to reduce drag in flow through insertion of energy promoters, and it is highly recommended to investigate the technique experimentally and extended numerically cases. © 2006-2016 Asian Research Publishing Network (ARPN). All rights reserved.