HYDRODYNAMIC CHARACTERISTICS OF MACROALGAE GROWN ON A LONG-LINE AQUACULTURE SYSTEM FROM PHYSICAL MODEL TESTS

David W. Fredriksson*, Bill Beaver, Adam St. Gelais, Andrew Drach, Longhuan Zhu, Tobias Dewhurst and Barry Costa-Pierce
 
United States Naval Academy
Annapolis, MD 21402
fredriks@usna.edu
 

The objective of this presentation is to describe the hydrodynamic characteristics of dense macroalgae grown on a long-line aquaculture system from a set of physical model tests.   The tests were conducted at the United States Naval Academy in the 116-m x 8-m x 5-m tank facility to obtain drag and inertial forces with a full-scale model.  The full-scale model was built considering the viscous force effects described by Reynolds number with geometric and material properties based on samples of Saccharina latissima obtained from sites in Maine.  The model was built to represent a 1-m section of a long-line with 3-m long macroalgae blades having a total weight of about 15 kg/m.  The experimental plan included a series of towing, wave and planar motion mechanism tests with the model mounted in both inline and normal configurations. Measurements obtained from force-block instruments were used to resolve forces related to velocities and accelerations.