| Home |
| Search |
| Today's Posts |
|
#11
posted to alt.sailing.asa,rec.boats.cruising,uk.rec.sailing
|
|||
|
|||
|
I trust you studied my numbers?
toad wrote: How does the windmill know the wind is not true wind? It has no concept of 'true' wind, it lives exclusively in apparent wind. It doesn't know the difference. Assume the windmill direct into wind concept works: You can take your windmill cart, put it on another cart and tow it at 20kts. It sees 20kts and will move forwards along its cart. If you stop the cart and blow 20kts at the windmill cart it will move forwards at exactly the same speed. Same speed *relative to the the surface it is on*. In other words there is some spare energy left over to drive the cart forwards after the energy required to hold the windmill in equilibrium with the wind is expended. In my example above that spare energy is used to drive the cart forwards but in your example of the windmill on the foredeck that surplus energy can be used to save petrol. Now we both accept that idea is laughable so you have to explain why it's not laughable when the wind blowing is caused by nature. ...but most importantly, why oh why oh why doesn't someone just post the mathmatical proof, the last time this came up I said I'd leave the thread 'till proof turned up and none did. Odd that. Lets take this step by step. Do you accept that it is possible for the cart to move directly upwind? Andy. |
| Thread Tools | Search this Thread |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Forum | |||
| NORDHAVN Rewrites Physics Textbooks | Cruising | |||
| No Rewrites Required! | ASA | |||
| The Physics of Paddling | General | |||
| Nordhavn 43 - What you think? | Cruising | |||
| Physics Question | General | |||