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As the savings are greater and the costs lower in the case of a newbuilding, the DMO has indicated that they will also consider the Hull Vane for their future newbuilds.
The paper written about this study can be downloaded here, and will be presented at the FAST 2015 Conference in Washington DC, from 1 to 4 September 2015.
Aug 1 16 11:31 PM
Oct 18 16 9:43 PM
Hull Vane's fuel-saving system showcased for the first time at Euronaval 2016Published: Tuesday, 18 October 2016 21:03 Euronaval 2016 is one of the leading international trade shows for maritime security, safety and naval defense. This year, The Dutch company Hull Vane is unveiling a proven solution to reduce naval surface ships’ fuel consumption by 10 to 15% and improve their seakeeping. Hull Vane is presenting an innovative fuel-saving system for the first time at Euronaval 2016 Recent research has shown a significant improvement of the comfort, safety and operability in waves of OPVs, corvettes and frigates. The reduction in propulsion power, propeller loading and stern wave also has a positive influence on the ship’s underwater noise signature. Helicopter and drone operations are made safer by reducing the vertical and horizontal accelerations of the helo-deck when sailing in waves.The Hull Vane system is a fixed hydrofoil positioned below or behind a ship's transom. It modifies the vessel's stern wave pattern and generates hydrodynamic lift with a forward component. This reduces the siph's resistance and dampens the pitching, heaving, rolling, and yawing.This system is particularly effective when used on relatively high speed vessels, or expressed in naval terms at Froud numbers between 0.2 and 0.7. For a 50 m vessel, this equates to a speed range between 8 and 30 knots. Similarly, for 100 m and 200 m vessels, this equates to minimum speed of 12 and 17 knots respectively.Ideal candidates for a Hull Vane include coastguard and naval vessels, ferries, cruise ships, supplys vessels and motor yachts.Hull Vane presents several case studies at the stand, focusing on the improved efficiency and seakeeping effect of the Hull Vane. One of these concerns a CFD study on the DTMB5415, a generic frigate-type hull form, whilst another one is about the effects of the Hull Vane on the 108 meter Holland Class OPVs of the Royal Netherlands Navy. A comparison between the effects of a Hull Vane, trim wedges and interceptors on a 50 m OPV hull form will also be shown.
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Silverstream Air Lubrication for Cruise Ship RefitPosted by Greg Trauthwein November 15, 2016Silverstream Technologies, makes of air lubrication technology for the shipping industry, signed a contract with a major cruise line to retrofit its proprietary Silverstream System on one of its vessels. The Silverstream System will be retrofitted onto the vessel in 2017. Extensive performance analysis of data from Silverstream’s original sea trial funded by Shell confirmed consistent net efficiency savings in excess of 4% and up to 8% for larger vessels.“There is a real demand from the cruise sector for clean technologies that are cost effective, easy to implement and operate, and deliver the efficiency benefits that are claimed," said Noah Silberschmidt, CEO Silverstream Technologies. "Cruise operators are under increasing pressure to improve their sustainability, as well as reduce fuel consumption and their environmental impact. This new contract represents the confidence that the sector has in the Silverstream System as a viable technology that helps them to meet these challenges, as well as delivering a fast return on investment.”The Silverstream System is an air lubrication technology which can be installed to both newbuilds and retrofits, even during a short dry docking. Critically, the technology does not take up a significant amount of space, which impacts revenue generation. “MARPOL Annex VI regulations, which will see the global sulfur limit in fuels reduce to less than 0.5%, will be implemented in 2020, and will have a significant effect on fuel bills for cruise operators, who also transit the 0.1% Emission Control Areas," said Silberschmidt. "Leveraging any solution that can reduce their fuel consumption is critical to maintaining profitability and continuity. Clean technology is one of the best ways to deliver this, and we are delighted that the hard work and investment that has gone into developing the Silverstream® System as one of the industry’s most viable and proven solutions is coming to fruition.”(Photo: Silverstream Technologies)
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Feb 7 17 1:00 AM
Vancouver Port Selects “PBCF” as Equipment DesignatedBy Joseph R. Fonseca February 6, 2017Mitsui O.S.K. Lines, Ltd. today announced that Propeller Boss Cap Fins (PBCF) was selected as a vessel quieting technology by the EcoAction Program implemented by Port of Vancouver, Canada. PBCF was jointly developed by MOL, West Japan Fluid Engineering Laboratory Co., Ltd. and Nakashima Propeller Co., Ltd. (Note 1), and is being sold by MOL Techno-Trade, Ltd. The Vancouver Fraser Port Authority’s EcoAction Program offers discounted harbour due rate to vessels that have implemented voluntary emission reduction measures and other environmental practices. As of January 1, 2017, vessels equipped with PBCF and transiting to the Port of Vancouver will be eligible for bronze level recognition and a 23% discount in harbour dues. PBCF was selected as a technology to reduce cavitation and therefore underwater noise which impacts marine mammals ability to navigate, find prey, mate and communicate. PBCF is an energy-saving device that reduces a vessel’s fuel consumption by 3% to 5% by breaking up the hub vortex generated behind the rotating propeller and improving propeller efficiency. PBCF’s effectiveness has been recognized around the world and the device has been installed on over 3,000 vessels since its introduction in 1987.(Note 2) In addition, water tank tests confirmed noise reductions of3 to 6 decibels in a specific underwater frequency range by breaking up the hub vortex. This feature resulted in PBCF’s selection by the Port of Vancouver for the EcoAction Program.PBCF is a product that protects the environment on different levels. It not only reduces CO2 emission by reducing vessel fuel consumption, but also is effective in protecting marine life, including whales, by reducing underwater noise caused by merchant vessels. The MOL Group continually contributes to environmental conservation in ports and at sea all over the world, and will step up its efforts to ensure safe operation and reduce environmental impact through the “ISHIN NEXT ~ MOL SMART SHIP Project” (Note 3). ---------------------------(Note 1) The company name in 1987 when PBCF was co-developed was Mikado Propeller Co., Ltd. In 2016, the company was renamedto current name.(Note 2) Press release on May 20, 2015: Energy-Saving Propeller Boss Cap Fins System Reaches Major Milestone - Orders Received for 3,000 Vessels(Note 3) Press release on November 24, 2016:MOL Launches "ISHIN NEXT - MOL SMART SHIP PROJECT -"
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MOL Rolls Out Refined PBCFBy Aiswarya Lakshmi May 19, 2017Image: Mitsui O.S.K. LinesMitsui O.S.K. Lines has announced that its group company MOL Techno-Trade will start selling an upgraded version of its energy-saving Propeller Boss Cap Fins (PBCF).MOL Techno-Trade has sold more than 3,100 PBCFs to ship owners all over the world. The new type of PBCF was jointly developed by MOL, Akishima Laboratories (Mitsui Zosen), and MOL Techno-Trade. The new design enhances propeller thrust and reduces torque thanks to refinements in fin shape and height. Tests of the new type PBCF on vessels in service confirmed an energy savings of around 5% compared to sister vessels not equipped with PBCF. The previous design showed an estimated 3% energy savings. The new PBCF design has already been patented around the world. The new PBCF is a "Simple and Tough" energy-saving device, which reduces CO2 emissions at the same rate as the fuel savings it generates. The PBCF was also selected as a vessel noise-reduction technology by the Port of Vancouver, Canada's Eco Action Program. While global environmental protection is in the spotlight today, demand for the new PBCF is increasing not only for its energy-saving performance, but also as an environmentally friendly technology. The MOL Group will develop the environment and emission-free businesses into one of its future core operations. The group continually promotes environmental conservation in ports and at sea all over the world, and will step up its efforts to ensure safe operation and reduce environmental impact through the "ISHIN NEXT - MOL SMART SHIP Project".
Jun 13 17 1:03 PM
Energy saving device Hull Vane presented to Asian naval sector at MAST Asia 2017 ConferencePublished: Monday, 12 June 2017 16:19While most exhibitors and presentations at MAST are focused on how to increase the impact of naval ships, very few are meant to reduce the impact (and costs). One such company is Hull Vane® BV, which will present its energy saving solution for naval ships at the MAST conference on Tuesday 13 June in session 5D – Advances in hydrodynamics. Typical Hull Vane configuration on patrol vessel Hydrofoil technologyInitially developed for an America’s Cup sailing yacht in early 2000, the Hull Vane® is a patented application of hydrofoil technology on displacement ships. It is particularly effective on those ships that combine a relatively high weight with a relatively high speed-to-length ratio. In addition to superyachts, ferries and certain offshore vessels, naval surface ships such as patrol vessels, corvettes and frigates correspond very well with this application range. On such ships, the Hull Vane® can achieve economies of 10-20%, while increasing the range and top speed. Reduced stern wave on DTMB5415 destroyer hull form. Without Hull Vane® (top) and with Hull Vane® (bottom) Operational profileIn the paper presented at MAST Asia, the Hull Vane® is compared to often used alternatives, such as trim wedges and interceptors. The chosen hull form is a generic fast displacement hull which is often used as a parent hull for naval ships. The results are consistent with CFD studies, model tests and full scale trials carried out with Hull Vane® on existing ships. The benefits are analysed for three different operational profiles for a similar 50 m vessel.Side benefitsWhile reducing the energy consumption is usually the main goal, the Hull Vane® has additional effects which are very desirable for naval ships. When a ship sails in waves, the Hull Vane® dampens the pitching and yawing motions, making helicopter landings safer and improving the performance of onboard systems and personnel. As the Hull Vane® reduces the stern wave, the propeller loading and the engine power for a given speed, the ship will also have a reduced acoustic (and visual) signature. On newbuild naval ships, the cost savings on engine power to reach a given speed are generally much higher than the cost of the Hull Vane. Retrofitting a Hull Vane® on existing naval ships typically has a payback period of one to three years.Maritime Innovation AwardAfter many years of development, Hull Vane® B.V. was established in 2014 and is located in Wageningen, the Netherlands. The Hull Vane® is now installed on five vessels, and seven more are currently under construction. Just recently, Hull Vane® won the 2016 Maritime Innovation Award from the Royal Institution of Naval Architects. Sales director Bruno Bouckaert will be available for meetings at MAST Asia Wake behind transom on patrol boat at 11 kn without Hull Vane® (left) and with Hull Vane® (right), leading to 25% lower fuel consumption
Jun 13 17 6:46 PM
“Nose Jobs” For Ships – Reason Behind Retrofitting Bulbous BowBy Sudripto Khasnabis | In: Naval Architecture | Last Updated on May 9, 2017 | 11 Minutes To ReadWe have discussed about the importance of the bulb shaped structure at the ship’s bow called the bulbous bow in our previous article. These huge protruding structures are so designed and fitted to reduce the drag and wave making resistance on a seagoing vessel.It is reported that large ships with conventional clipper bows can have 12-15% more fuel efficiency when coupled with a bulbous bow. Moreover, seakeeping characteristics have also improved inclusion of bulbous bow in the design (reduction in pitching, improved buoyancy of the fore part).However, there are certain conditions that determine whether a bulbous bow would improve the fuel efficiency.When a ship sails, it generates waves by imparting energy to the water particles around it. There are layers of fluid around the ship’s body and certain parts of the ship are responsible for this ‘system’ of waves generated as a result of the abrupt curvature at the ship’s stem, owing to the rise in pressure. This is because the ship is not stationary and the motion across the viscous fluid layers creates differences in pressure at various points – some regions of positive pressure and some negative, ultimately giving rise to two wave systems, broadly, the transverse and the divergent wave systems.Now, when a bulbous bow is included in the ship’s design, the waves are generated in front of the bow. For a ship without a bulbous bow, the waves would have formed at the stem and the ship will have to overcome these wave crests which become higher with increasing speed. The bulbous bow waves form slightly forward of these crests. If at a certain speed the trough of this system almost coincides with the crest of the normal bow wave, the bulbous bow is successful in achieving its aim.The various bow configurations to choose from for possible modification. (Reference: Practical Ship Design by D.G.M. Watson)The phenomenon in action where the steep waves at the bow are cancelled is called destructive interference; a wave phenomenon involving the interference of waves in opposite phase. This is how the vessel with a bulbous bow running at optimal speed is able to keep the water at the fore end relatively calm as opposed to a normal clipper bow.Three main hull parameters are of importance here – block coefficient, length/beam ratio and the beam/draft ratio. The block coefficients vary over a large range and so design charts are available for the same.The combination of Froude number/Block Coefficient at which a bulbous bow will be of any advantage. (Reference: Practical Ship Design by D.G.M. Watson)The graph shown above is used to decide whether a bulb would be able to bring down the overall resistance of a vessel or not. The Watson and Gilfillan line on this plot is an indication for the same and superimposition of this line on the various observations in the plot give us some idea. First, the vessels having finer forms (CB < 0.6) and operating at higher speeds (Froude Number, Fn >0.3) will benefit from the addition of a bulb. So will ships having much fuller forms (0.725 < CB < 0.825). However, bulbous bows can offer advantages on ships of all block coefficients provided they are ‘over-driven’ and are not too ‘fine’ for the speed at which they operate (Remember the length/beam ratios?).Bulbous bows come in a range of shapes and sizes tailoring to the needs of the parent vessel. However, a broad classification refers to whether a bulb has been ‘faired’ with respect to the hull or there exists a steep curvature with respect to the stem line, which is the case with an ‘added’ bulb. The ‘added’ bulb is easier to manufacture and integrate. It also provides good results when compared to a ‘faired’ bulb.Some of the physical modifications in nose jobs are optimisation of the bulb’s volume, centre of volume extended vertically along with longitudinal extension. Basically the bulb shape is modified into what is called a ‘reverse pear-shaped’ section and this works well for working drafts below design drafts. The waterlines of the bulb nose are required to be streamlined but not circular to avoid the possible separation of water flow around it.Today, research is being done on using polymer or thermosetting plastics for the highly complex bulb designs since a ship’s bulb is not exposed to high heat in normal working conditions and such materials are easier to work with than steel.Slow Steaming and Bow DesignSlow steaming is a strategy which is used by several shipping companies to improve fuel efficiency. The basic principle here is to operate the ships at a fraction of their rated working power with a certain reduction in speed to achieve savings in the exceptionally high fuel expenses. These savings are capable of offsetting the reduction in propulsive efficiency.Then, there came certain provisions to accommodate the slow steaming strategy such as redesign of propellers, introduction of slow steaming kits and ship nose jobs, particularly in container vessels. Sometimes, removing the bulbous of a vessel and reverting to the good old clipper bow is also a feasible option.Now when nose jobs were being considered a viable option, a shipping market, where time means money, immediately latched onto it- the container shipping industry. Since ship nose jobs can involve replacing the bulbous bows of ships for better performance in slow steaming environments, today container shipping companies such as Maersk Line are leading from the front in replacing the ‘nose’ of their vessels. Almost a dozen ‘nose jobs’ have been done by now which claim to have gained fuel savings of around 5% which is huge for the size of container vessels in use. Even the payback period for the expenditure behind a ‘nose-job’ is estimated to be less than a year.While there are benefits with modified ship bulbous bows providing fuel savings, there are other advantages too. Ship nose jobs have been verified to have reduced CO2 emissions by around 23% (NYK Group) over a period of 6 months, eventually leading to savings in bunker consumption.A naval architect may design a vessel for a certain design speed. But, it would not hurt to do some market research and find out the operating speed and engine operating ratings for such vessels so that the bow operation and other elements of the design can accommodate itself (for optimal efficiency) within the current shipping trends.
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