You should also investigate the Engineering / Technology Links on our Links Pages. Browse these links to become aware of the types of technology information available on the net. Especially check out the sites with the label.
Check the list of topics at the top of our Other Useful Links Page and see if the topic you are interested in is listed there. If it is follow the links and they should take you to the respective technical areas.
Note! The Engine Technology Items are in the Engine Development Folder.
Also, you can search the Patent areas for your topic. Some instructions for how to best do that are in our Patent Folder. Also you should keep an eye on the New Patents Section of our Patent Folder.
You can also use the normal net search engines (Yahoo and Lycos, etc) to search for your topic.
Lloyd's List : CANADIAN-manufactured azimuthing propulsion systems have been specified for a revolutionary class of US-conceived harbour tug.
Vancouver-based specialist designer and producer Ulstein Maritime (UML), part of Norway's Ulstein Group, will supply the drive units for each of the 4,000 bhp ship docking modules (SDMs) ordered by Hvide Marine.
Fort Lauderdale-based Hvide initially contracted two SDMs from US shipbuilder Halter Marine. Last week the programme was augmented with a commitment to a third such vessel. The unusual new design has main dimensions of 76 ft length and 50 ft beam, with a draught of just over 16 ft.
Each of the harbour tugs will employ Ulstein 1650H-type Z-drives rated for a 2,000 bhp input at 1,600 rev/min, and turning twin, nozzled propellers. Two Caterpillar 3516 engines will deliver an aggregate power output of 4,000 bhp. Contracts have so far been formalised for the first two vessels.
The Ulstein drives will be mounted forward and aft and offset from the centre, so as to exert equal propulsive effect in all directions.
The 1650H units will be supplied in 'hull-mounted' configuration whereby the Z-drive mounts through the hull and projects below the keel. Placed in this manner, it is claimed, the counter-rotating propellers will have virtually unobstructed water flow, enhancing the efficiency and manoeuvrability of the SDM.
Maximum bollard pull will be available in all directions, regardless of hull orientation.
The contract with Hvide follows the recent selection of the Ulstein equipment for several other US projects. UML has been awarded six shipsets of its 1350H units by Wisconsin shipbuilder Marinette Marine Corporation for the US Coast Guard's new fleet of WLM-class coastal buoy tenders.
The Canadian firm has also been selected by Smith Maritime of Hawaii for two 1650H systems for its new reverse tractor tug Namahoe, under construction at the Marco Seattle yard.
In addition, US operator Cook Inlet Tug & Barge has chosen UML model 900H units for its new azimuthing destined for service in Alaska.
UML is the largest supplier of fixed pitch Z-drives to markets in North America. Over 55% of all Z-drive tugs and more than 90% of Z-drive propelled US-flag offshore support vessels use UML systems. The factory at Vancouver was established in 1946 and has been a unit of Ulstein since 1984.
The WLM class of coastal buoy tender from Marinette Marine represents the first use of UML's Z-drive technology by the US Coast Guard. Each of the six vessels will employ a pair of model 1350H units in hull- mounted configuration, permitting removal without the need for drydocking. The lower sections of the drives will be heavily constructed in cast steel so as to withstand high ice loadings.
As the vessels will incorporate a comprehensive dynamic positioning (DP) package, the azimuthing units will be equipped with nozzles to improve thrust while station-keeping.
Although nozzles are not often specified for ice-classed, proprietary Z- drives, as ice can become entrapped, Ulstein has overcome potential problems by using specially designed propellers.
The propeller's special skew, formulated by Ulstein's hydrodynamics department, offers maximum propulsive efficiency while reducing entrapped ice and, therefore, loads imposed on the gear train. Navigation in ice has been further enhanced by an optimised underwater shape designed for the USCG.
[03-22-97 at 13:41 EST, Copyright 1997, Lloyd's of London Press]
The January 1997 issue of Popular Science has an article titled, "Flying on Water" on pages 50-54 that has some great photos and test describing the current wave skimming WIG craft that use the added lift wings receive near the water to make a boat truly fly at a short height above the water. We scanned a figure from the article that shows a "takeoff" and explains the ground effect. The Russians did a lot of work with this technique on very large craft a few years ago. Now the technology is being moved to smaller potentially recreational craft. The model featured in the story is a "Flarecraft".
Flarecraft Corporation was formed by Bill Russell who has spent 9 years developing the "ground effect" planes. Flarecraft now has 5 working prototypes and the author rode in one on Rhode Island's Narragansett Bay. A water jet from a jet ski is used to steer the craft on the water and to assist in "taking off". A 225 horsepower aircraft engine provides the power for "flight" and propells the Flarecraft to speeds in excess 100mph. This winter prototypes will be flying in Los Angeles, St. Louis, and Miami. Ticom Corp a division of Northrop AIrcraft and Merifield Roberts Corp are beginning to manufacture a "hundred or so" of the 5 seaters with a retail price in excess of $200,000. Russell is already working on a two seater personal version that would fit on a trailer and sell in the $10,000 range.
December 5, 1996 - A lab in England has established a web page describing their research in the area of composite propellers.
The Russian Krylov Shipbuilding Institute in St. Petersburg has been working on Ventilated Water Jet Propulsion and Reducing Hull Friction by the use of Gas Cavities. The status of their research is given in a U.S. Navy Technology Newsletter. Note! They are looking for U.S. Partners in the continuing development of the Ventilated Water Jet.
"High Tech Materials in Boat Building" is an excellent article on the use of new boat hull materials.
The August September 1993 issue of International Boat Industry had an article titled, "Blowing Bubbles", that described a new water-jet propulsion system, the Bubbly Jet, currently under development in Israel. Gas is injected to water that is already moving through a jet due to the motion of the craft. The air or gas expands and increases the exit velocity of the water. There are no moving parts interfacing with the water. The pressure of the gas regulates the speed of the craft. The concept had been under development for 9 years and the project was being led by Professor Alon Gany with the Faculty of Aerospace Engineering at the Israel Institute of Technology (Technion) in Hafa. Development had reached the stages of both static and dynamic testing in the laboratory and they were hoping to soon develop a full size version for practical trials.
A Michael S. Triantafyllou and his brother George S. Triantafyllou at M..I.T. have been working on a Robotic version of a Tuna. They received U.S. Patent #5,401,196 and quite a bit of press in 1995. The March 1995 issue of Smithsonian magazine had a very lengthy article which was also their cover feature. The article was titled, "An Efficient Swimming Machine". The header line said, "Instinctive control of vortices lets fish swim the way they do. A robotic tuna has also managed it; boats and submarines may be next."
One of the basic concepts is described in a sketch caption, "Fish encountering vortices senses the pressure variations of the spinning eddies as they move along its side. To capture energy from the vortices and boost its swimming efficiency, the fish instinctively times the flapping of its tail to counter rotating whorls that meet and weaken the encountered ones.
Another article was in the February 23, 1995 issue of Machine Design on pages 18-20. The 44 inch long 'Robo Tuna" with 2,843 parts is described and its testing in a 120 foot test tank is explained.
A brief article, "Mechanical Tuna", appeared in the December 1994 issue of Popular Science on page 17. It talks of the design focusing on trying to transfer natural fish like movements to underwater craft.
A major article, " Something's Fishy About this Robot" in the August 2000 Issue of the Smithsonian (Pages 54-60) covers the MIT Robo Tuna and mentions some similar developments being worked on in other research facilities. Portions of the article are temporarily available on the Smithsonian's site.
The August 1996 issue of NASA Tech Briefs describes the use thermal blanket insulation from the space shuttle to help insulate the drivers compartment of a NASCAR race car. Work was done on a Penske Ford Thunderbird using the Thermal Protection System (TPS) blanket material. Bobby Allison started the work and used one of his friend's (Roger Penske's) cars. In actual track conditions the temperature under the drivers foot went from 145 degrees F to 108 degrees F. The temperature under the drivers left elbow went from 260 degrees F to 120 degrees F. These readings were obtained with only the external insulation in place. Greater changes were expected when running with some interior insulation in place. Rockwell is negotiating a business development contract with Penske Racing to develop a commercial product for the NASCAR application. The article say to call Bruce Lockley at Kennedy Space Center (407) 861-5381 for more details. You can also read more of the article on the NASA Tech Briefs web site.
These materials might be applicable to high performance and race boat applications today and perhaps later to more applications as they become more commercially available.
The September 23, 1996 issue of Business Week Has an article titled, "Batteries Not Included" on pages 78-80. It describes and electric car without the normal huge batteries. It uses a 60 HP gas turbine engine and a flywheel. The flywheel can add in as much as 200 HP. Harold A. Rosen, age 70 and his brother Benjamin Rosen, age 63 are the men behind it. Harold led the team that built the first geo-stationary satellite at Hughes Aircraft in 1963 and Ben is ex-chairman of Campaq Computers. They have converted a few cars to their method and have only recently "came out of the closet" to expose their designs.
Sounds like a method that might someday be applied to boating? The flywheel helps you get "over the hump" to get on plane and then you cruise on the gas turbine with the flywheel being a big help to "pop up" skiers. They mention a composite flywheel (light weight and no rust?) Might be food for thought?
Since most recreational boats are propeller powered, There is an opportunity to learn from others using propeller type devices. Airplane propellers have been studied very thoroughly, but they run in a much different medium. Water turbines have very similar operating characteristics and problems as ducted propellers. One difference is that many turbines are designed for single speed operation, however, some are not. Two excellent articles to start with in this area are:
Tank agitators, industrial mixers, and stirring devices are another field from which drive manufacturers could learn. Some large industrial mixing devices look incredibly like outboard motors. They operate like huge kitchen mixers. Some interaction with the body of knowledge associated with these devices could provide some new ideas for both fields.