Project Motivation:
Marine current turbines offer a potential source of renewable energy, but the accumulation of organisms such as barnacles and algae on underwater surfaces, known as biofouling, degrades turbine performance and lifetimes. Biofouling on cross-flow turbines specifically hasn’t been experimentally studied and has extra motivation due to the upcoming installation of cross-flow turbines at Pacific Northwest National Laboratory’s Marine Sciences Laboratory.
The accumulation of biological communities on PMEC’s Adaptable Monitoring Package after a five-month deployment in Sequim Bay at the Marine Sciences Laboratory.
Summary:
The team set out to evaluate changes in turbine power output and structural loads at various stages of barnacle colonization on turbine blades. A real barnacle, taken from the shores of Puget Sound, was 3-D scanned, modeled, and patterned on the surface of turbine blades at three different sizes and densities using 3-D printing techniques.
(a) Three-dimensional barnacle scan used to generate fouling model. (b) CAD model of “fouled” turbine blade covered in barnacles. (c) Fully assembled turbine showing blades and struts fabricated using additive manufacturing.
Experimental test matrix.
The fouled turbines were then tested and measured in the Alice C. Tyler flume at the University of Washington’s Harris Hydraulics Laboratory.
Testing setup and facility.
Current Results:
The impact of barnacles on turbine power output was found to be substantial and, for the most severe cases of fouling, the turbine does not produce power at any rotation rate. Conversely, barnacle fouling was found to have minimal impact on structural loading. To maintain generation capacity over extended periods, these results highlight the importance of antifouling coatings and proactive blade cleaning.
Figure showing how turbine performance changes with barnacle accumulation.
Research Team:
More information:
Carl Campbell Stringer, Implications of Biofouling on Cross-flow Turbine Performance, Masters Thesis, University of Washington, June 2019. - paper, presentation
Sponsor:
This project is supported by NAVFAC. The project team gratefully acknowledges discussions with Ben Maurer, Rob Cavagnaro, Andy Stewart, and Ramona Barber.
Last updated: June 19, 2019