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Author Topic: Solar windmill for catapaulting probes...  (Read 4597 times)

Offline Titanscape

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Solar windmill for catapaulting probes...
« on: 30/11/2004 07:18:45 »
What do you think of the idea of a large bladed space station weighted right with release clasps for projecting objects in space into selected trajectories. It could rotate quite fast using angled sails and could slow down for a new pick up by changinging sails angles...

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Offline chris

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Re: Solar windmill for catapaulting probes...
« Reply #1 on: 30/11/2004 08:42:30 »
And the sails would be powered how, by solar radiation ?

Chris

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Offline Titanscape

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Re: Solar windmill for catapaulting probes...
« Reply #2 on: 01/12/2004 08:33:18 »
By solar wind and coronal mass ejections.

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Offline chris

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Re: Solar windmill for catapaulting probes...
« Reply #3 on: 01/12/2004 08:36:46 »
So why would it rotate, rathen than just be pushed along ?

Chris

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Offline Titanscape

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Re: Solar windmill for catapaulting probes...
« Reply #4 on: 04/12/2004 16:19:48 »
Chris, it would be shaped like a fan, like a Dutch windmill.

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Offline chris

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Re: Solar windmill for catapaulting probes...
« Reply #5 on: 04/12/2004 21:19:23 »
Yes, but a windmill is anchored to the ground. In space such a windmill would surely be pushed along, rather than turning, because there would be no fixed point for it to rotate around ?

Chris

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Offline gsmollin

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Re: Solar windmill for catapaulting probes...
« Reply #6 on: 07/12/2004 04:43:22 »
I think it would rotate and translate. If the mirrors are arranged like a pin wheel, then the reaction force would push the wheel as well as turn it, assuming the wheel is facing the sun.
 

Offline deordiedaz

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Re: Solar windmill for catapaulting probes...
« Reply #7 on: 05/05/2006 22:00:56 »
windmill could be fixed to a huge space station
 

another_someone

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Re: Solar windmill for catapaulting probes...
« Reply #8 on: 06/05/2006 02:47:46 »
quote:
Originally posted by chris
Yes, but a windmill is anchored to the ground. In space such a windmill would surely be pushed along, rather than turning, because there would be no fixed point for it to rotate around ?



Not strictly a requirement think of the European Sycamore seed does not need an anchor in order to spin.

What is true is that in order to spin, it needs positive airspeed (or, in the case of the solar wind, it needs a positive wind speed), thus if it were to float free of gravitation effect, it would gradually increase its speed until it was at the same speed as the prevailing wind, and then there would be no relative wind speed, and so no pressure it could use to rotate the blades.  So long as it is anchored by gravity, then this should not be a problem.



George
 

another_someone

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Re: Solar windmill for catapaulting probes...
« Reply #9 on: 06/05/2006 03:10:48 »
quote:
Originally posted by Titanscape
What do you think of the idea of a large bladed space station weighted right with release clasps for projecting objects in space into selected trajectories. It could rotate quite fast using angled sails and could slow down for a new pick up by changinging sails angles...



Firstly, if it is to be driven by the solar wind, then it must be constantly facing the wind, and rotating in a plane that is perpendicular to the wind.  Since the centrifugal forces will only be in the same plane as the plane of rotation.  This would mean that it could only catapult objects in a north-south direction (i.e. out of the plane of the Earth's orbit), or in a direction that is tangential to the Earth's orbit.  It could not catapult a projectile directly towards the Sun, or directly away from the Sun (of even slightly towards or away from the Sun).

Secondly, it would be quite a difficult job to speed up and slow down the windmill effect.  If these sails are to gain any reasonable amount of energy in any reasonable time, they must have absolutely gigantic sails, and you will have to find some way to easily change the angle of these gigantic structures.

It would also be advantageous to keep such a device well away from the Earth, which means you would still need to get you object up to this windmill by some other means.  The reason for wishing to keep such a thing well away from the Earth is because it will have to orbit the Earth, and not only would it cast a significant shadow over the Earth (as well as being an obstruction to navigation), but when it gets behind the Earth, it will be in the shadow of the Earth, and will lose the solar wind in that shadow by being further from the Earth, the Earth will cast less of a shadow over it, and it will cast less of a shadow over the Earth.

Also, you would really like to keep such a device balanced.  In order to do that, you would have to release two object in opposite directions; otherwise, when you release only one object, the windmill will be out of balance.



George
 

Offline Titanscape

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Re: Solar windmill for catapaulting probes...
« Reply #10 on: 15/05/2006 05:54:58 »
It could be computer maintained like those new US fighter bombers. And like a kite.

Using the Earth's gravity to swing an object into outer planet or inner planet reaches. Going in the direction of the Earth around the sun and with each catapult, a simultaneous ejection the other way. It's position between Earth and Moon. Or beyond the moon loading in the axis.

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Re: Solar windmill for catapaulting probes...
« Reply #10 on: 15/05/2006 05:54:58 »

 

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