Rasmussen Maritime Design

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Working catamaran, optimized displacement hull with Flowbow and Flowstern

5.7 knots Fn = 0.242

6.2 knots Fn = 0.261

6.5 knots Fn = 0.275

6.9 knots Fn = 0.294

7.4 knots Fn = 0.314

7.7 knots Fn = 0.327

8.3 knots Fn = 0.353

8.9 knots Fn = 0.379

9.5 knots Fn = 0.405

9.9 knots Fn = 0.418

Resistance vs. velocity

Reduction in resistance for optimized 15meter catamaran  displacement vessel with Flowbow® and Flowstern

At 8.2 knots, resistancereduction approx. 45%​
At 9.4 knots, resistancereduction approx. 55%​
At 10.6 knots, resistancereduction approx. 57%​
At 11.7 knots, resistancereduction approx. 55%

Reduction in fuel/energy consumption per distance versus velocity.

The graphs show considerable reduction in fuel/energy consumption per distance, compared to traditional hull design, as velocity increases.
This also allow vessels to be operated at considerable higher cruising speed with good fuel economy.

Model test results, resistance vs. velocity for displacement hull vs. redesigned hull with Flowbow® vs. redesigned hull with Flowbow® and Flowstern.​

Data from model testing is to be up scaled from model to full-scale vessel, resulting in a greater percentage reduction of the resistance than shown in model testing.