Promas With Nozzle Offers Imporved Fuel Efficiency

MarineLink.com
Wednesday, June 05, 2013

Promas is a Rolls-Royce propulsion system that integrates the open-water propeller and rudder of a conventional shaftline into a hydrodynamically-efficient entity.

A tapered hubcap is fitted to the hub of the propeller and leads the water flow on to a bulb which forms part of the spade rudder. The rudder has a twisted leading edge, optimized for the flow from the propeller, which converts into additional forward thrust some of the swirl energy in the slipstream that is normally lost.  According to the manufacturer, Promas installations on merchant vessels have given propulsion-efficiency improvements up to 6-8% on new buildings, and up to 15% on upgrades of existing vessels.

Building on this success, Rolls-Royce has further developed the Promas system to suit applications where there is a requirement for a high bollard pull, such as anchor-handling offshore vessels (AHTS) and tugs. The operational profile of many offshore vessels is different from merchant ships, requiring both a large pulling power at low speed and a high free-running speed in transit.

The Promas with nozzle system is designed for these varying operating modes, in the case of anchor-handlers offering an increase in propulsion efficiency in both modes. The complete AHTS installation comprising Promas with nozzles and optimized propellers and rudders, can reduce fuel consumption in transit by 15%, and in some cases more, with a consequent cut in emissions. It can also improve the bollard pull by typically 5%.

This system unites a new type of nozzle with an optimized propeller, hubcap, rudder bulb and a special rudder profile. Components are designed to work together to provide a ducted system, maximizing efficiency and minimizing disturbances to the water flow both through and around the nozzle. The profile of the InnoDuct nozzle for the new Promas system has been developed through CFD analysis and testing, and represents a major advance on the 19A profile which is used for conventional nozzle propeller installations.

Water flow leaving the nozzle interior passes over a rudder of special profile developed to provide very high steering side forces yet minimum drag. Depending on the exact requirements the rudder may be either a one piece design or a medium flap type.

Maritime Reporter August 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Marine Propulsion

Gas Turbine Acceptance Test Completed for S. Korea Navy

Rolls-Royce has reached a milestone in the Republic of Korea Navy’s FFX frigate program, with the successful completion of acceptance tests for the MT30 gas turbine.

Mercury Marine Launches Repower Financing

Mercury Marine launched a new repower finance program that aims to make it easier for consumers to get the engine performance they want with flexible financing for a broad range of buyers.

MN 100: Twin Disc, Inc.

1328 Racine Street Racine, WI 53403 Telephone: 262 638 4000 Web: www.twindisc.com President and CEO: John H. Batten Number of employees: 990 The Company: Twin Disc designs,

Fuels & Lubes

Upcoming Winter Tanker Market Same as Last Year?

Will the 2014/15 winter tanker market be a repeat of the previous one? Poten & Partners consider the question in their latest 'Poten Tanker Opinion'. As the

MN 100: Total Lubmarine

Le Diamant B – 16, rue de la République 92922 Paris-La-Défense Cedex, France E-mail: rm.total-lubmarine@total.com Web: www.lubmarine.com The Company: Total

Brent Oil Hits 26-month Low Under US$97

Brent crude oil on Monday slumped to its lowest in over two years, below $97 per barrel as lacklustre economic data from China, the world's top energy consumer,

Marine Equipment

Gas Turbine Acceptance Test Completed for S. Korea Navy

Rolls-Royce has reached a milestone in the Republic of Korea Navy’s FFX frigate program, with the successful completion of acceptance tests for the MT30 gas turbine.

Mercury Marine Launches Repower Financing

Mercury Marine launched a new repower finance program that aims to make it easier for consumers to get the engine performance they want with flexible financing for a broad range of buyers.

The Switch to Deliver Full-Power Converter for Floating Power Plant

Vancouver-based Water Wall Turbine Inc. (WWT) has selected The Switch to provide a 500 kW full-power converter for its self-floating power plant. This new system

Vessels

Survey Vessel Delivered to Fugro N.V.

Fugro Pioneer is the second of three vessels to be delivered to Fugro in 2014. Fugro has taken delivery of the second of the three Fugro Offshore Coastal Survey

Mexican Navy Contracts Damen for Two Vessels

Secretaria de Marina orders seventh patrol vessel and a fast crew supplier In August 2014 the Mexican Navy (Secretaría de Marina) and the Netherlands’ Damen

Ferus Smit Building LNG Powered Cement Carrier

The first unique LNG powered ship that Ferus Smit has on order for Erik Thun A.B. will be built and equipped as a dedicated cement carrier. The ship will be delivered to the joint venture JT cement,

 
 
Maritime Careers / Shipboard Positions Maritime Contracts Offshore Oil Pod Propulsion Port Authority Salvage Ship Repair Ship Simulators Shipbuilding / Vessel Construction Winch
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1891 sec (5 req/sec)