Turbulent Drag Reduction by Biopolymers in Large Scale Pipes

Abstract

In this work, we describe drag reduction experiments performed in a large diameter pipe (i.d. 100mm) using a semirigid biopolymer Xanthan Gum (XG). The objective is to build a self-consistent data base which can be used for validation purposes. To aim this, we ran a series of tests measuring friction factor at different XG concentrations (0.01, 0.05, 0.075, 0.1, and 0.2% w/w XG) and at different values of Reynolds number (from 758 to 297,000). For each concentration, we obtain also the rheological characterization of the test fluid. Our data is in excellent agreement with data collected in a different industrial scale test rig. The data is used to validate design equations available from the literature. Our data compare well with data gathered in small scale rigs and scaled up using empirically based design equations and with data collected for pipes having other than round cross section. Our data confirm the validity of a design equation inferred from direct nu- merical simulation (DNS) which was recently proposed to predict the friction factor. We show that scaling procedures based on this last equation can assist the design of piping systems in which polymer drag reduction can be exploited in a cost effective way

Drag Reduction Using Polysaccharides in a Taylor–Couette Flow

“…With increasing angular velocity, the difference between the dimensionless torque for the water and for the polysaccharide solutions is observed to increase with this phenomenon being most pronounced for pineapple fibers. This is in good agreement with the observations made by Campolo et al [ 24 ] for xanthan gum in pipe flow.…”

Role of Bio-Based Polymers on Improving Turbulent Flow Characteristics: Materials and Application

“…To apply those experimental concepts to the design of a polymer-induced drag reduction piping system, Campolo et al [ 67 ] ran a series of drag reduction experiments using a semi rigid bio-polymeric xanthan gum in a large diameter pipe. Through cost-effectiveness analysis, they found sets of operating conditions for the profitable use of xanthan gum as DRA, including an analysis of the DR% data under different conditions and the value of the cost of combining the energy/polymer prices with the pipeline characteristics.…”

“…Through cost-effectiveness analysis, they found sets of operating conditions for the profitable use of xanthan gum as DRA, including an analysis of the DR% data under different conditions and the value of the cost of combining the energy/polymer prices with the pipeline characteristics. Furthermore, they also observed that both the increase of shear viscosity and shear-thinning behavior for increased xanthan gum concentrations in a turbulent flow condition [ 67 ].…”

Drag reduction behavior of hydrolyzed polyacrylamide/xanthan gum mixed polymer solutions

“…In the macroscopic scale, those variations result in large drag reduction. However, mechanical degradation of polymer solutions complicates their use (Campolo et al 2015;Moussa and Tiu 1994). Several theories have been proposed to explain mechanical degradation of polymer solutions, among which extreme stretching of polymer chains and scission of the polymer chain have been most accepted (Rodriguez and Winding 1959).…”