Development and performance at high Reynolds number of a skin-friction reducing marine paint using polymer additives

• Published in: Ocean engineering Vol. 84; pp. 183 - 193
• Main Authors: Woo Yang, Jeong, Park, Hyun, Hwan Chun, Ho, Ceccio, Steve L., Perlin, Marc, Lee, Inwon
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.07.2014; Elsevier
• Subjects: Antifouling marine coating; Applied sciences; Buildings. Public works; Exact sciences and technology; Fluid dynamics; Fundamental areas of phenomenology (including applications); Ground, air and sea transportation, marine construction; Marine construction; Materials; Paints and renderings. Protection products; Physics; Polymer injection; Self-Polishing Copolymer (SPC); Skin frictional drag reduction; Toms effect; Turbulence control; Turbulent flow control; Turbulent flows, convection, and heat transfer; Self-Polishing Copolymer (SPC); Toms effect; Skin frictional drag reduction; Polymer injection; Antifouling marine coating; Turbulent flow control; Turbulent flow; Skin friction; Antifouling paint; Experimental study; Marine environment; Large Reynolds number; Polymer flooding; Drag reduction; Test facility; Flow control; Ship
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2014.04.009

A skin-friction reducing marine paint has been developed by mixing fine powder of PolyEthyleneOxide (PEO) with Self-Polishing Copolymer (SPC) Anti-Fouling (AF) paint. PEO is well documented as an effective drag reducing additive that exhibits the Toms effect. Friction drag reduction has been implemented by injecting aqueous polymer solutions into the turbulent boundary layer of liquid flows. However, such polymer injection is usually achieved through penetrations in the solid flow boundary, which is a significant practical obstacle to marine application. Here, we explore the use of a PEO infused marine coating to deliver the polymer molecules to the near-wall flow. The erosion mechanism of SPC paint resin and the subsequent dissolution of PEO lead to the controlled release of PEO from the painted surface. The direct force-balance measurement in a high-speed circulating water channel demonstrated a maximum 33% skin friction reduction relative to conventional AF paint. From local shear stress measurements the skin friction coefficient of the present paint was lower than that of a smooth, uncoated surface, thereby demonstrating the turbulence modification due to the polymer additive. From measurements in a tow tank, the skin frictional drag was found to decrease by approximately 10% compared with conventional AF paint. •PEO powders were combined with marine paint to exhibit skin frictional drag reduction effect.•The release mechanism of PEO from the paint was identified to be self-polishing mechanism of resin.•The present method proved to be an efficient delivery system for polymer drag reducing additive.•Compared with baseline AF paint, maximum skin frictional drag reduction is found to be 30%.•The present paint shows lower skin friction than that of smooth surface, proving Toms effect.