Cruising & Sailing Information

Some Taiwan scientists have figured out a way to reduce the wake from ferries crossing the harbor, most harbors and lakes, many rivers have speed limits to reduce the wake which cases hardships accidents, inconvenience and damage to other craft. We have all heard of the gentleman who ended up between the dock and hull of a large boat and was crushed to death, so obviously it is a serious matter. Yet speed on the water saves time and means greater profits more movement in less time means more efficiency. In places like Taiwan with the insanely high populations, there are serious needs getting all the people where they need to be.

By redesigning the hulls in a wavy fashion they are able to reduce significantly the wake. Mr. Cheng-Hung Huang has come up with a wavy design, which reduces wake. Here is the design.

http://www.newscientist.com/data/images/ns.../99996368F1.JPG

Here is the premise:

http://else.hebis.de/cgi-bin/sciserv.pl?co...87_atihcphfbcgm

Now then let's take this concept and apply it to a winglet on a heavy airliner, cargo aircraft or military troop transport. We know the winglets help reduce drag and wing tip vortices and wake turbulence, which is quite a violent disruption, which moves a lot of air. For instance if you google NASA's LARC project you will see the studies done.

http://www.dfrc.nasa.gov/Gallery/Movie/B-7...EM-0073-01.html

http://www.dfrc.nasa.gov/Gallery/Movie/C-5...EM-0085-01.html

Now then in the Mr. Cheng-Hung Huang model the researchers designed their Ferry Catamaran hulls for both deep water and for shallow water. This would work for both dense and less dense air, which takes into consideration the changes in altitude for the aircraft. Now realize the airfoil is different than the hull in that the hull of a ship is going through fluid that is 750 more dense than air, yet the same principles do apply in limited sense. So even if the wavy design is somewhat less exaggerated on the winglets of an aircraft the savings in wing tip vortices could be significant and therefore more efficient flight.

The hull design in this case is a perfect compromise shape for efficiency between the salt water and fresh water since the two have different densities. Instead of a normal sleek hull designs they have designed a hull with bizarre contours at specific intervals. The peaks are set at 24, 68 yards from the bow with the trough 44 yards. These very same techniques in fluid dynamics occur in aerodynamics

The research would indicate that as long as the dimensions were proportional the concept could be used on any length simply by adjusting the position of the convex peaks and concave troughs in proportion to the hull length. So if the winglets on an A340 or a C-17 are 68 inches then the trough would be at 44 inches. As the air flows across the wing up onto the winglet. For the fuselage of an aircraft the same thought could be used. And you thought those old B-52's needed to be re-skinned just because they have 500,000 TT Airframe hours and are wavy and worn out? No actually they may actually work better that way to reduce induced drag and with a little modification work exceptionally better, interesting no doubt. Should intakes of jet fighters be contoured along this concept? To reduce fan blade ware and tear and smooth airflows to help produce maximum smooth and sustained inflows and thrust? The answer is yes. Most likely the compression and Bernoulli principle will not effect this only help it flow through by allowing the air to hug the surface and lower the boundary area. If we learn that such an effect compresses the air to a greater degree, while allowing it to flow, then that information is equally as valuable in hypersonic intakes and engines.

Wing tip vortices are so violent and move so much air we had even considered the wind energy potential to power up runway lights or blue tax lights. You may want to google that for a recent study which was done.

We should look into these ideas for aircraft fuselages and tail sections, as well as UAVs, smart munitions and airships. Is this something that should be taken into consideration on the 7E7? We know that wing tip vortices and wake turbulence have sound. Sound causes a signature, if we wish to reduce the signatures of sound the tops of the stealth UAVs might wish to have the wavy surface? A UUV or Submarine would also benefit by reducing it's acoustic signature since a submarines safety depends on not being able to be detected. There is much benefit to this concept for the insides of engine intake tubes to reduce harmonic damage, increase airflows and the friction associated with the boundary layer for temperatures. It also makes sense for the outside of a submarine hulls, Torpedoes, 18 Wheeler tanker trucks, blimps, nose cones on bullet trains, propeller blades or aircraft fuselages.

"Lance Winslow" - If you have innovative thoughts and unique perspectives, come think with Lance; www.WorldThinkTank.net/wttbbs