Underwater shear-based grooming of marine biofouling using a non-contact Bernoulli pad device

Abstract

The biofouling removal ability of a shear-based device was tested on two submerged surface types, Garolite G-10 and Intersleek 1100SR. Each surface was groomed at four frequencies along with a control group. The seven-week grooming study was conducted in Narragansett Bay, Rhode Island. The Bernoulli pad device uses confined radial outflow to generate both surface-normal forces to grip the submerged surface and shear stress to groom the surface without contact. An image-processing algorithm was developed and used to assess the effectiveness of the various grooming protocols, along with direct measurements of chlorophyll a per surface area. The image-processing data showed that the grooming resulted in ∼50% cleanliness on the Garolite at the end of the study whereas the Intersleek was continuously restored to nearly its initial clean state. Chlorophyll a data supported these overall conclusions. These results indicate that surface cleanliness can be maintained effectively on Intersleek using frequent shear-based grooming.

Keywords:

• Bernoulli pad
• grooming
• shear stress fouling release image processing
• chlorophyll a

Acknowledgements

This work was supported by the Office of Naval Research under the Navy Undersea Research Program, grant N00014-16-1-3051 to Michigan State University and the Multi-Institutional Collaborative Grant from University of Massachusetts Dartmouth. The authors would like to thank Maria Medeiros for providing the opportunity to conduct the research and Dr Geoffrey Swain and Dr Kelli Z. Hunsucker at Florida Institute of Technology’s Center for Corrosion and Biofouling Control (CCBC) for useful discussions and material support for the field test by painting the Garolite plates for the study. The authors also thank Natasha Dickenson from NUWC for technical assistance and Mark Menesses for allowing his previously published figure to be adapted.

Disclosure statement

No potential conflict of interest was reported by the author(s).