Mesh properties for rans simulations of airfoil-shaped profiles: A case study of rudder hydrodynamics

A good mesh is a prerequisite for achieving reliable results from Computational Fluid Dynamics (CFD) calculations. Mesh properties include mesh types, computational domain sizes, and node distributions. However, in literature, we found no clear consensus about what these properties should be. In this article, we performed a case study on ship...

Sixty years of research on ship rudders: Effects of design choices on rudder performance

Rudders are primary steering devices for merchant ships. The main purpose of using rudders is to generate forces for course keeping and manoeuvring. In exceptional cases, rudders are also used for emergency stopping and roll stabilisation. Furthermore, rudders affect propeller thrust efficiency and total ship resistance. Therefore, rudders...

Hydrodynamic characteristics of multiple-rudder configurations

The manoeuvring performance of inland vessels is even more crucial than that of seagoing ships due to more complex navigation environment. One of the most effective possibilities to improve ship manoeuvrability is to change the rudder configuration. Twin or even quadruple rudders and high-lift profiles are widely applied to inland vessels. When...

3D RANS simulations of shallow water effects on rudder hydrodynamic characteristics

An accurate estimation of the rudder forces and moments is essential for manoeuvrability prediction. Previous research has shown that ships have different manoeuvring performance in deep and shallow water. Before considering the rudder’s contribution to shallow water manoeuvring, it is meaningful to analyse the shallow water effects on the...

Interaction effects on hydrodynamic characteristics of twin rudders

In order to reach the required manoeuvrability, inland vessels often use twin rudders, but the interaction effects are poorly understood. To achieve a proper configuration, this paper applies 2D RANS simulations to analyse the interaction effects on the twin-rudder hydrodynamics. Various twin-rudder configurations with different profiles and...

Impacts of the rudder profile on manoeuvring performance of ships

The profile of a ship rudder influences the forces it generates, which in turn influence the manoeuvring performance of a ship. Thus, rudder forces and moments should be calculated considering the profile. Instead of an empirical estimation of the rudder normal force coefficient, this paper applies a RANS method to determine the hydrodynamic...

Impacts of rudder profiles on ship manoeuvrability

The performance of a ship’s rudder largely determines its manoeuvrability, which includes turning ability, initial turning ability, yaw-checking ability and course-keeping ability. However, existing empirical formulas for rudder forces do not concern the rudder profile. This paper discusses the impacts of various rudder profiles on ship...

Hydrodynamic Characteristics of Twin-Rudders at Small Attack Angles

RANS simulations are implemented to analyse the hydrodynamic characteristics of twin-rudders, i.e. Flat plate rudders, NACA rudders, and Wedge-tail rudders. The study mainly focuses on small attack angles. Results show that the NACA series is the most efficient profile while the Wedge-tail rudder has the highest rudder effectiveness.

Design guidelines and empirical evaluation tools for inland ships

For inland ships, state-of-the-art hull form design is to a large extent based on experience, common sense, or adjusting previous designs. The idea therefore arises that further optimization is possible if the right knowledge is available. This knowledge is insufficiently available due to two main reasons. First, research into inland ship...

A proposal for standard manoeuvres and parameters for the evaluation of inland ship manoeuvrability

Inland ship manoeuvrability has more complex features than that of sea-going ships due to constrains of inland waterways and complicated ship configurations. In order to clarify the complexity of manoeuvring, impact factors of navigation environment and ship particulars are first analysed to point out the determinants for evaluation. After...