Comparisons of Flow Patterns over a Hierarchical and a Non-hierarchical Surface in Relation to Biofouling Control

Abstract

Biofouling can be defined as unwanted deposition and development of organisms on submerged surfaces. It is a major problem as it causes water contamination, infrastructures damage and increase in maintenance and operational cost especially in the shipping industry. There are a few methods that can prevent this problem. One of the most effective methods which is using chemicals particularly Tributyltin has been banned due to adverse effects on the environment. One of the non-toxic methods found to be effective is surface modification which involves altering the surface topography so that it becomes a low-fouling or a non-stick surface to biofouling organisms. Current literature suggested that non-hierarchical topographies has lower antifouling performance compared to hierarchical topographies. It is still unclear if the effects of the flow on these topographies could have aided in their antifouling properties. This research will use Computational Fluid Dynamics (CFD) simulations to study the flow on these two topographies which also involves comparison study of the topographies used. According to the results obtained, it is shown that hierarchical topography has higher antifouling performance compared to non-hierarchical topography. This is because the fluid characteristics at the hierarchical topography is more favorable in controlling biofouling. In addition, hierarchical topography has higher wall shear stress distribution compared to non-hierarchical topography

Three-Dimensional Numerical Simulations and Antifouling Mechanism of Microorganisms on Microstructured Surfaces

“…It was also found that with the increase of Re and the ratio of particle radius to microridge height, the number of deposited particles decreased. Bin Ahmad Fawzan et al [23] compared the antifouling performance of hierarchical and non-hierarchical topographies. Simulation results expressed that the range for wall shear of hierarchical topography is between 0.00281 Pa and 0.00452 Pa, while non-hierarchical topography is between 0.00165 Pa and 0.00301 Pa. Lee et al [24] studied the shear stress distribution on a prismatic surface by simulations and suggested that a high shear stress was generated on the surface of the prismatic structure; hence, shear stress was considered as the main antifouling factor of the microstructured surface.…”

Study on the Effects of Microstructural Surfaces on the Attachment of Moving Microbes

“…With an increase of Re and a/h, an "inaccessible area" for suspended particles was formed near the surface of the microstructure membrane, thus reducing the deposition of particles. Fawzan et al [20] compared the antifouling performance of hierarchical and non-hierarchical topographies. Simulation results expressed that the range for wall shear of hierarchical topography is between 0.00281 Pa and 0.00452 Pa while non-hierarchical topography is between 0.00165 Pa and 0.00301 Pa. CFD was also applied to study the heat transfer characteristics of microstructures [21].…”