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A proper design of the mooring systems for Wave Energy Converters (WECs) requires an accurate investigation of both operating and extreme wave conditions. A careful analysis of these systems is required to design a mooring configuration that ensures station keeping, reliability, maintainability, and low costs, without affecting the WEC dynamics. In this context, an experimental campaign on a 1:20 scaled prototype of the ISWEC (Inertial Sea Wave Energy Converter), focusing on the influence of the mooring layout on loads in extreme wave conditions, is presented and discussed. Two mooring configurations composed of multiple slack catenaries with sub-surface buoys, with or without clump-weights, have been designed and investigated experimentally. Tests in regular, irregular, and extreme waves for a moored model of the ISWEC device have been performed at the University of Naples Federico II. The aim is to identify a mooring solution that could guarantee both correct operation of the device and load carrying in extreme sea conditions. Pitch motion and loads in the rotational joint have been considered as indicators of the device hydrodynamic behavior and mooring configuration impact on the WEC.

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This paper presents an overview of the Lecco Innovation Hub project and in particular to the Sailing Yacht Lab project a10 m length sailing yacht which aims to be a full scale measurement device in the sailing yacht research field. A description of scientific framework, measurement capabilities as well as of the principal design, building process, project management and commissioning is provided with some examples of preliminary collected data obtained during the first sea trials. Finally an overview of the ongoing project tasks and future project developments is provided including potential research and knowledge achievements for sailing yacht research field

The sustainable design of small passenger vessels and large size pleasure craft indicates new trends: lower speed, reduced fuel consumption and better seakeeping in all range of velocities. Small amplitudes of roll motion are considered one of the most important comfort parameter. These trends call for reviewing some commonly used concepts and designer practice. Fundamental parameters as metacentric height and midsection form affect comfort as well as ship safety in counteracting way. Round bilge, due to good seakeeping characteristics and to large amount of available data from systematic series is the most common hull form choice when cruising speed implies displacement or semi displacement mode. Hard chine hull forms are generally chosen when relative speed leads to some hydrodynamic lift, although recently they have been considered for low relative speed. They allow simplified and cheaper construction and among their interesting features is higher roll damping. This appears very attractive for craft that are generally fitted with stabilizing systems and ask for the most reduced roll motions at any and zero speed. This paper presents the results of experimental tests relative to roll decay of two ship models of the same dimensions, displacement and GM values: they have the same warped bottom hull form developed at University of Naples, the first is hard chine and the second has round bilge from transom to midship. Both of them are suitable for displacement and semi-displacement craft operating at medium-low relative speed. The tests have been carried out at University of Naples towing tank, in calm water, at Fn ranging from 0.0 to 0.45. Natural roll frequencies and linear and non linear damping coefficients are reported for all tested speeds allowing a fair comparison of the roll characteristics due to the variation in hull form.