| ||||
|
#121
| ||||
| ||||
| like to mention the 1899 lord brabizon's giro sail i saw in the program wind driven on discovery channel point was made that apart from hi/lo side the tipspeed of the 2 blades having apearant wind advantage |
|
#122
| |||
| |||
| Windmaster, I think Rick's solar/wind boat is highly relevant to this thread. This thread is about using a wind turbine to provide a means of forward propulsion. It is important to consider all the ways that a windturbine can do this. This means considering the hull(s) that the turbine is pushing, and the way the energy is utilised, and in what kind of water you wish to do this. Focusing on the turbine alone could lead to premature conclusions. Rick's highly efficient, 'go anywhere' design shows a solution to a wind turbine with no wind. |
|
#123
| |||
| |||
| Not Really - Please read the original question carefully. Maybe the original poster can tell us what he meant. Quote:
Why not start another thread if you want to talk about something different? |
|
#124
| ||||
| ||||
| Windmaster, Much earlier, I contributed some thoughts to this thread, and my perception of the meaning of his question is that Duma Tau knew in phrasing it, that the ultimate sailboat, by definition, cannot sail directly into the wind. A sailboat or sailing boat is a boat propelled partly or entirely by sails. A sail is any type of surface intended to generate thrust by being placed in a wind, in essence, a vertically-oriented wing. When the boat traveling is across or into the wind, the sails propel the boat by redirecting the wind coming in from the side towards the rear. In accordance with the law of conservation of momentum, air is redirected backwards, making the boat go forward. This driving force is called lift although it acts largely horizontally. http://en.wikipedia.org/wiki/Sail A wind powered vessel is another matter and the solution should be capable of being scaled up to the size of a commercial freighter. As is known, the heat of the sun contributes to the winds, so utilising some of the other forms of power from the sun, by more direct methods in order, to assist the wind powered vessel's capabilities makes commercial sense. This is, to my mind, a legitimate and acceptable example of lateral thinking. Let us not be "limited by the terms of the enquiry" in the weasel words of national governments, but expand oor minds to include all types of designs that avoid the direct use of fossil fuels as motive power. We are seeking to convert the sun's energy for immediate or later use as a fuel to propel a vessel. Fuel is stored energy, whose origin is from the sun, be it coal, crude oil, or even hydro power. Electricity is a fuel although the ignorant call it energy and it is available by conversion processes with which we are all familiar, when it is required. So, pencils at the ready, let us attack the proposition once more with gusto. Pericles |
|
#125
| ||||
| ||||
| Quote:
![]() |
|
#126
| ||||
| ||||
| Teddy, That's very true. The reports you hear in the MSM talk about an energy crisis when they should say fuel crisis. Energy can be neither created, nor destroyed. You and I and most of those who post here know that. Reporters should be stood up in a line and--------------!!!! The Norwegians have hydro power that works, but Tajikistan cannot make their new Russian funded hydro power system work. http://news.bbc.co.uk/1/hi/programme...nt/7243704.stm Regards, Pericles |
|
#127
| |||
| |||
| I don't want to argue with anyone. I think we can all relax when it comes to "off topic" contributions. If it is relevant in some way....then welcome it. Everybody wins. If you are bored you can just skip past the article. I don't like to see interesting people disappear when they are 'brushed off'. (Not speaking about Rick so much....just people in general). Some people lerk in BoatDesign.net and offer a lot of their time...because they are interested in a subject....only to be accused of being not helpful enough, or off topic, or this or that....and they just go away (probably can't be bothered with the arguments). And then I think....man...I was interested in that, but now I will have to go elsewhere too. Everybody just stay cool ![]() |
|
#128
| |||
| |||
| Would a wind turbine with ducting around it be better or worse? Quieter and safer but heavier? |
|
#129
| |||
| |||
| Quote:
I determine the best turbine design for this application will have lightly loaded blades so tip losses are not that significant. You might gain a little in energy recovery from the airstream but this will be lost + more in pushing the shrouding through the air. On a boat, the extra weight up high is unlikely to be appreciated either as it reduces stability. It will increase roll inertia, which could be good or bad depending on the boat. Rick W. |
|
#130
| |||
| |||
| Hi Chaps! In total isolation my own experiments with what I liked to call Interface Machines began with sails and keels, then progressed through many variations of wings and fins, sails and wheels, until finally settling down to rotating sails and rotating keels. Hence the term I prefer for my Interface Machinery is Rotary Sails! Why be so bl..dy pedantic... Cheers, Lin... |
|
#131
| |||
| |||
| I'm sorry Rick, but many of your facts reflect old technology. Try to listen and learn, unless you try to do this your pedal craft will not improve. Those who stand on the shoulders of giants can see further... This old geezer is forever looking for taller giants. Rotary Sails have much in common with aircraft propellors. The principle is reversible. Once again, symmetrical foils, high revolutions, clutches, flywheels, hydraulics, electrics, self adjusting foils and transonic tips. Even the old Sunderland propellors went transonic during take-off! Cheers, Lin. The best |
|
#132
| |||
| |||
| Hello Richard. I like ducts, but they are difficult to make. A simple narrow shroud encircling the blades works well. There is a patented ships propeller with the shroud cast on it. I much prefer that the blades remain free to rotate axially. A high speed, small diameter, free-wheeling prop in fine pitch can readily out-pull a large spinnaker. Multiple Rotary Sails have the capacity to power an ocean liner at speed against the Trade Winds. Cheers, Lin. |
|
#133
| |||
| |||
| Quote:
When talking about powering a boat directly from a air turbine it is good thinking to compare each windblade to a sail and each underwater prop blade to a keel - it leads to success, I have found. Rick, on the other hand (correct me if I am wrong) has no plans to power a prop directly from a wind-turbine. |
|
#134
| |||
| |||
|
#135
| |||
| |||
| Quote:
The transmission is not a lot different to what is seen on large equipment like this: http://www.komatsu.com.au/equipment/...fications.aspx In this case the energy source is a diesel engine rather than a wind turbine. I also have the advantage with the electric transmission in strong wind to store energy and in low wind to use the stored energy to maintain my speed. This is similar to modern hybrid cars being able to store energy when braking only the wind provides my energy source. My back-up energy collection is solar energy. I have compromised on the size of the air blades such they simply will not provide the required thrust to enable energy recovery from the water blades when I am going downwind but I will ballance thrust between the water prop and the air prop depending on windstrength to conserve energy. Rick W. |
![]() |
| Thread Tools | Search this Thread |
| Display Modes | |
| |
Similar Threads | ||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Electric motors for solar-powered boats | Twointense13 | Boat Design | 3 | 01-07-2011 08:21 PM |
| Windmill in the Roaring Forties | Wendy | Boat Design | 5 | 11-07-2008 03:16 PM |
| Small 60 - 90 degree tunnel to get bigger prop viable ? | globaldude | Sailboats | 1 | 08-15-2006 02:16 PM |
| Bugatti engine powered boats | rivaaquarama | Powerboats | 0 | 06-08-2006 04:26 PM |
| True wind/apparent wind? | pygmalion | Boat Design | 5 | 12-09-2004 07:52 AM |