Through the use of CFD and FEA design tools, CJR-designed rudders are tailored to your specific hull form and optimised for peak performance and longevity. With an accurate understanding of the flow into the rudder from the propeller and the hydrodynamic loading, as well as the ability to calculate rudder stock and blade strength requirements and supporting bearings reactions with precision accuracy, CJR provides the finest rudders on the market.
Design and manufacture can meet any classification society rules, including all IACS societies, and rudders can be cast in a range of materials to suit the specific application, with nickel aluminium bronze (NiBral) or high tensile bronze representing the most popular choice of material, Equally, CJR’s rudders, can be manufactured using a range of alternative approaches to best meet your needs.
Flow-Aligned Twisted Rudders
Although traditionally motor yacht rudders are straight, they operate in an area of uneven water flow directly behind the propellers. As a result, a suction pressure peak can form at or near the leading edge of the rudder. Through another unique CJR innovation, we are able to accurately simulate these forces and can predict how they would impact the propulsion system’s performance. With this comprehensive understanding, we’re able to design a rudder with a unique ‘twisted’ profile – one which is perfectly aligned with the propeller flow angles along the entire span.
Key Features of Twisted Rudders
- Optimised profile of each rudder delivered through CFD.
- Significantly improved propulsive efficiency, with no impact on vessel manoeuvrability or steering performance.
- Reduced rotational losses and minimised drag provide the potential to increase top speed by up to two knots.
- Power savings provide the opportunity to reduce engine load by up to 3% at the same RPM, in turn significantly reducing fuel burn.
- Lower suction pressure peaks to reduce cavitation, noise and vibration, improve both ride comfort and rudder lifespan.
- Potential to downsize the steering rams to save weight and cost.
- Manufactured to any classification society rules, including all IACS societies.
We are able to satisfy any required construction approach, with experience across all major methods.