As Nor-Shipping is one of the most important events in the industry calendar, this was a significant gesture from Becker. The company proudly estimate a 1.4 million tonne reduction in CO2 emissions thanks to all of the ducts currently in circulation. The presentation of the duct, one of Becker’s most successful products, was a bold statement from a company seeking to achieve greater environmental sustainability in the vast global shipping industry.
The milestone duct was put on display at the entrance to the fair, painted in green to symbolise its environmental cause and decorated with a large number “1000” in bold, green digits. Following its appearance at Nor-Shipping, the 1,000th duct is to be fitted onto a 22,000 cubic-metre LPG carrier.
Also featured at Nor-Shipping was the Becker Twisted Fin®, another energy saving product similar to the Becker Mewis Duct®, but designed for faster ships with speeds of 18 knots and above.
Simplex-Turbulo is proud to be the official and exclusive UK agent for Becker Marine Systems, based in Hamburg.
The concept of the Becker Mewis Duct®
High blocked ships have low propulsion efficiency. The reasons for this are the bad wake field and high propeller loading. Water inflow has such an unfavourable characteristic that the propeller must operate in bad inflow conditions. The Becker Mewis Duct® harmonises and stabilises the flow and generates a pre-swirl to reduce rotational losses in the propeller slipstream.
The Becker Mewis Duct® consists of two strong fixed elements mounted on the vessel: a duct positioned ahead of the propeller together with an integrated fin system within. The duct straightens and accelerates the hull wake into the propeller and also produces a net ahead thrust. The fin system provides a pre-swirl to the ship wake which reduces losses in propeller slipstream, resulting in an increase in propeller thrust at given propulsive power. Both effects contribute to each other.
The achievable power savings from the Becker Mewis Duct® are strongly dependent on propeller thrust loading, from 3% for multi-purpose ships up to 8% for tankers and bulkers.