Contrapel's Above the Water-Line Propeller System

Press Release
Tuesday, October 23, 2012

Marine propulsion research & development company, Contrapel Ltd has released details of its new propulsion system for boats – the system set to make future boats more economical, manoeuvrable, safer, stronger and better for the environment.



The high-speed propeller was invented over 170 years ago and has dominated the propulsion market ever since.  Despite 60 years of development, water-jets have struggled to make significant inroads.  



Shown to an enthusiastic marine industry for the first time at the recent Auckland On Water Boat Show, the Contrapel Hybrid Drive is about to change that.  The system is so advanced that it carries out all the functions of both propellers and water-jets with none of the drawbacks of either.  



“The Contrapel technology is a propeller system working above the waterline. Externally it resembles a traditional water-jet, however internally the method for developing thrust has much more in common with conventional propeller systems,” says Contrapel founder and Managing Director, Barry Davies.  



The Contrapel drive uses a pair of contra-rotating, fully enclosed hybrid propellers, capable of operating above the water line.  The mode of operation of the hybrid propellers is to accelerate the water from out of the intake (pick-up) duct and then discharge it through the outlet, requiring only enough backpressure downstream from the propellers to keep the system primed.  This contrasts with the traditional jet, which does not accelerate the water until further downstream in the nozzle section, which requires the generation of high pressure.  



The Contrapel Hybrid propellers produce lift in a similar way to open water propellers, by using slippage.  The use of hybrid propellers enables the mass component for each revolution be maximized and the plume velocity to be minimized. This contrasts with the low mass per impeller revolution and high-plume velocities present in conventional high-speed water-jet designs.



According to Contrapel’s own on-water tests, the higher efficiency of the new system provides the following improvements compared with boats that are equipped with traditional jet drive installations:

1) Vastly improved thrust at low and mid speeds
2) Better fuel economy at low and mid speeds due to vastly improved control.
3) Highly survivable and operable in extreme conditions, including brown and black-water environments.
4) Will lower global marine carbon footprint
5) Significantly lower noise and vibration levels
 


“Unlike the propeller however, it’s a complete solution for the entire global industry, since it’s scalable to all sizes and works equally well above or below the water line.”



The rotating speeds of the hybrid propellers are also very low, which generates low noise and little wake turbulence.  The Contrapel Hybrid Drive boasts “propeller-like” thrusts at all speeds, but unlike propellers the Contrapel Hybrid Drive propellers are enclosed in a stainless steel tube that is screened to ensure objects cannot be ingested.  This means that animal life; people and fragile seascapes are protected from damage.  



“All propeller systems are limited by virtue of the exposed nature of their rotating blades.  Outboards, stern-drives, surface piercers, shaft-drives etc. are a liability when operating in unknown and shallow waters - one strike and the craft is out of action.


Exposed propellers are a danger to civilians and trained operators in the water and are extremely vulnerable to propeller strike with objects floating under the water line or on the surface. Contrapel eliminates all of those risks and liabilities.”

Where the Contrapel Hybrid Drive also excels are the benefits over high-speed water-jets. The system has a high tolerance to wear caused by small particles in the water, equating to minimal performance loss due to damage or wear.
 


“Compared with all high-speed water-jets and propellers, expensive maintenance is considerably less.”



Currently tested in 190mm, 270mm and 330mm diameter configurations, the Contrapel Hybrid Drive is able to suit a variety of marine propulsion applications, and will work on smaller leisure craft right through to military vessels, shipping, work boats, dredging vessels and will even work for underwater submarines.



“The Contrapel Hybrid Drive system is completely scaleable and will offer entirely new ways to solve problems encountered in just about every sphere of the marine industry.”  



One of the world’s leading boat manufacturers, New Zealand’s Stabicraft Marine have been involved in the development of the Contrapel Hybrid Dive, and in conjunction with Contrapel Ltd have fitted two Contrapel 330 units to a 10.2m Supercab rescue vessel.

Powered by twin Volvo-Penta D6 435hp engines, the Stabicraft 10.2m weighs 8 tonnes and carries 750litres of fuel. It can achieve a fast cruise of 29.7 knots @ 3030rpm and reach a top speed of 37knots @ 3500rpm.

 

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

New Products

NMEA Awards Top Electronic Makers

Marine electronics experts named 11 products in nine categories as winners of the 2014 NMEA Product Awards. Once again, Furuno USA was named Manufacturer of the Year--Support.

Renewable Energy: Schottel Tidal Turbines Ready For Use

In the last months Schottel  successfully tested its hydrokinetic turbines in Strangford Lough, Northern Ireland. The full-scale tests included 260 operating hours under realistic conditions.

New Intermodal Rail Service from PortMiami

Florida East Coast Railway (FECR) and PortMiami, through a strategic alliance, are offering the Sunshine Gateway service, which includes on-dock intermodal rail capabilities.

Shipbuilding

Catamaran Passenger Ferries Delivered in Angola

Incat Crowther announced the delivery a pair of 30m catamaran passenger ferries, Macôco and Panguila, to Instituto Marítimo e Portuário de Angola. The vessels, built by Astilleros Armon in Spain,

Offshore Oil: Lamprell Completes Caspian Sea Drilling Unit

UAE-based Lamprell said that it completed construction of the second Caspian Sea jackup drilling rig, Mercury, for service in the Caspian Sea.   "I am delighted

TRIYARDS Buys into Aluminium Shipbuilding Expertise

TRIYARDS Holdings Limited, an offshore vessel fabrication and engineering solutions provider to the oil and gas (O&G) industry, has added new capabilities, products

Ship Repair & Conversion

Mitsubishi Super Skiving System

Mitsubishi Heavy Industries, Ltd. (MHI) has completed development of the "Mitsubishi Super Skiving System" for machining internal gears with high speed and outstanding precision.

Messer to Debut MetalMaster Xcel

Messer Cutting Systems said it has answered the call from manufacturers that have been demanding a faster, more accurate way of producing cut parts. Messer’s

Rolls-Royce Expands in the Canary Islands

Rolls-Royce announced it has signed a cooperation agreement with the Astican Shipyard in Las Palmas, Canary Islands that it said will enhance the service capabilities

Marine Power

B COOL Acquires MEMAC

With the acquisition of MEMAC, B COOL A/S now offers customers one entry to multiple maritime systems – both refrigeration solutions and monitoring of the engine

Singapore’s MPA Discuss LNG Bunkering

The Maritime and Port Authority of Singapore (MPA), Antwerp Port Authority, Port of Rotterdam and Port of Zeebrugge participated in a Liquefied Natural Gas (LNG)

Mitsubishi Super Skiving System

Mitsubishi Heavy Industries, Ltd. (MHI) has completed development of the "Mitsubishi Super Skiving System" for machining internal gears with high speed and outstanding precision.

Naval Architecture

New Standard for LNG Cargo Containment Systems

Wilhelmsen Technical Solutions (WTS) said it has successfully completing the gas trial for the first LNG carrier built to a Boil Off Rate (BOR) of 0.08% per day.

Performance by Design: Hydrodynamics for High-Speed Vessels

The new book “Performance by Design: Hydrodynamics for High-Speed Vessels” will be introduced on October 30 at the Fort Lauderdale International Boat Show, Donald L.

NMRA Awards Scholarship to Yacht Design Students

The National Marine Representatives Association (NMRA) awarded two scholarships to students pursuing careers in the field. Noah Luff of Ventura, California is one

 
 
Maritime Careers / Shipboard Positions Maritime Security Maritime Standards Pipelines Port Authority Ship Electronics Ship Repair Ship Simulators Sonar 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: 0.3425 sec (3 req/sec)