SKEG – Impact of Skeg Alternatives on Resistance and Yaw Stability
2022 – 2025

Preliminary investigations have shown that skegs have a significant impact on ship resistance. Initial studies on the resistance of a twin-screw vessel confirm this trend. However, the skeg plays a crucial role in course stability and the effort required for construction and docking of ships. Therefore, alternative systems with lower resistance need to be developed, taking these factors into account.

In this R&D topic, the aim is to demonstrate the impact of skeg alternatives, such as fixed fins and/or enlarged rudder areas, on resistance, power requirements, as well as rolling behavior and course stability. Power savings, particularly in alternative power supply systems such as batteries or fuel cells, lead to significant weight, space, and cost reductions due to the scalable nature of storage systems. Since the proposed alternatives are not expected to involve significantly higher construction effort but may result in cumulative weight and resistance effects, resistance-reducing measures are generally of great interest to shipyards and ship operators, especially in the context of rising fuel prices.

The project aims to develop replacement systems for skegs that provide the same yaw stability while reducing ship resistance. The development of these alternatives will be carried out using numerical flow simulations. Model tests will provide insights into power requirements, rolling behavior, and maneuvering characteristics with the replacement systems. The development will focus on two different types of twin-screw vessels, as these are considered to have the highest application potential. The fundamental assumption is that a fully submerged fin can generate greater lift for the same surface area compared to a hull-integrated skeg. This hypothesis will be tested within the scope of this research topic.