A Novel Model for Measuring Tensions Between the Floater and Bag of a Closed Flexible Fish Cage

Abstract The closed flexible fish cage is made of flexible materials such as nylon and is considered an alternative to the conventional net cage. Although the tension between the floater and bag of a closed flexible fish cage is crucial for its operational safety, no experimental research has focused on it due to the difficulties in its measurement. This study designed and constructed a scale model with a novel structure that enables indirect measurement of this tension. The model consists of a floater, a bag, and four embedded load cells between them. Rational results obtained for motion and tension suggest the successful establishment of the model design and experimental method. Furthermore, the study confirmed that the tension includes significant nonlinear and constant components in addition to the primary first-order component. As the incident wave period increases, the first-order component decreases while the second-order and constant components increase.