Wind Powered Car moves 2.8 times faster than the wind

[wooferhound]

http://www.physorg.com/news194851568.html

The car is able to move faster than the wind because the propeller is not turned by the wind. The wind pushes the vehicle forward, and once moving the wheels turn the propeller. The propeller spins in the opposite direction to that expected, pushing the wind  backwards, which in turn pushes the car  forwards, turning the wheels, and thus turning the propeller faster still.

[bob g]

how about some cat 5 hurricane force winds?

can you say, "yahoooooooooo"



bob g

[boB]

Interesting...   I know that sailboats can sail faster than the wind too, by tacking, but they don't go in quite the same direction as the wind.
Is this similar ?

[wooferhound]

This is going directly downwind
The article linked is fairly informative . . .

I do kind-of wonder though, how can the wheels power the Prop, then the prop powers the wheels ?

[bob g]

something just doesn't feel right about that theory,

not quite sure, but it smacks of some overunity problem

i can't see how you can produce enough power from the prop to drive the car,when the car supposedly is what
powers the prop?

bob g

[ghurd]

something just doesn't feel right about that theory,

not quite sure, but it smacks of some overunity problem

i can't see how you can produce enough power from the prop to drive the car,when the car supposedly is what
powers the prop?

bob g

I agree.

In fact, the way I read it, it sounds like Taylor could use his 3.5HP B&S motor to get his (or that) car going, then it would keep going.

The power for the prop comes from the wheels, which comes from the wind.
When the car and wind are going the same speed, there is no power to overcome friction?
When the car is going faster than the wind, the power is supplied by the propeller, which gets its power by the wind pushing the car, which it can not do if the car is faster than the wind.

Instantaneous speed (or nearly) comparisons could be effected by the blades acting as a flywheel, 
which with some creative data manipulation could be shown as some kind of proof of concept.
G-

[Bruce S]

I looked at the responses below the posting.
One of the designers has been answering questions and seems honest enough, they will be taking the design to NALSA for confirmation.

In the sailing world both water & ice the tacking and such are common place. I couldn't find any OU anywhere.

Don't think I could park in front of my house though .

Cheers
Bruce S


 

[wooferhound]

Don't think I could park in front of my house though .

It's not a wind generator sir,
it's a car . . .

[TomW]

Don't think I could park in front of my house though .

It's not a wind generator sir,
it's a car . . .

Oh, my. It looks like a Cuisinart for birds.

I am skeptical myself but thats another story.

Carry on.

Tom

[Bruce S]

Don't think I could park in front of my house though .

It's not a wind generator sir,
it's a car . . .

Correct on that but being that it's 5 meters tall , it would hit the light poles each time I drove in/out. Then there's those pesky overpasses on the way to/from work

Cheers
Bruce S

[Bruce S]

Don't think I could park in front of my house though .

It's not a wind generator sir,
it's a car . . .

Oh, my. It looks like a Cuisinart for birds.

I am skeptical myself but that's another story.

Carry on.

Tom

It would BE a conversation starter for sure.

Wonder how many tickets one cold get the first time out on the highway  .

Cheers
Bruce S

[taylorp035]

In fact, the way I read it, it sounds like Taylor could use his 3.5HP B&S motor to get his (or that) car going, then it would keep going.

Right.  Our supermileage car only ran the engine for 2-4 seconds, and it pushed the 300 lb car from 10 to 25 mph.  It coasted for about 1-2 minutes, depending on how flat the road was.  On pump gas and some cheap parts, anyone could build a car that gets 300- 500 mpg IMHO, which would be super cheap to operate.  Probably cheaper than an electric powered scooter or a fancy non-working windmill car  .

[XeonPony]

cheaper then an electric scooter? Once invested in photovoltaic cells it can't get any cheaper

[Bruce S]

cheaper then an electric scooter? Once invested in photovoltaic cells it can't get any cheaper

You beat me to the post 
This work thing got in the way...
I would totally agree.
I think taylorp035 was merely joking too  .
Our 48Vdc E-scooter has paid for itself a full year ago, charge time even going the very inefficient route of charging up a bank of NiCds to run an inverter to run the battery charger for the 48V bank of batteries still is way cheaper than fuel. Of course there is more energy stored in the petro-based fuel...

Cheers
Bruce S 

[XeonPony]

Indeed, Using an Mppt controller I run my cells at 30volts Vmp So after I hit float I just switch over the cells right into the 24v pack of the scooter, don't even need to buy a controller! just a simple dirty little cut off circuit.

[stop4stuff]

dunno what the big fuss is about, its only mechanics & engineering that converts traditional sail based tacking into a straight line... and when you consider that the point to point straight line speed of this vehicle (2.8x) is still slower in comparision than say an ice yacht tacking (3-4x point to point, 6-7x ground speed) with the same windspeed, its not really that remarkable... just very, very different... you can make your own model too... http://www.youtube.com/watch?v=T-ArigMKhi4

[zap]

I went through this thread and many of the comments on the site woofer gave but I still couldn't wrap my head around how it would work.
This youtube video finally explained it in a way I could understand.
http://www.youtube.com/watch?v=k-trDF8Yldc

This video uses a a bit bigger model than the one in stop4stuff's link.
http://www.youtube.com/watch?v=aJpdWHFqHm0

[taylorp035]

I came back to this thread because I finally believe that the model may work.  This seems like a fun project for an engineering competition or something of the like.

I wonder if it would work better with a better shaped windmill blade?  Maybe try and improve upon the 2.8x value.   Sounds like a good supermileage car to me  .

Once you get above a threshold ground speed, I guess you could travel in any wind direction, right?
Going into the wind would cause the car to go forwards automatically. 
Going down wind was proven the guy I think....  Once you got above the air velocity, the energy from the wheels would have to go into pushing the air to go into the blades... that doesn't work.  But once you are going into the wind, it is just like if you are going into a head wind.
A cross wind has no power and you can't get something for nothing, so you would have to have a swivel mount on the blades. 

The video on the treadmill (stop4stuff)  was convincing in the fact that the energy has to come from somewhere (the treadmill).  The same can work in reverse with the wind. 

[zap]

Have a look at this video taylor... I find it mesmerizing.


http://www.youtube.com/watch?v=oKqC5JsurOk&feature=related

[taylorp035]

Couldn't you use a VAWT too?  Seems like it would solve a few problems.

[zap]

I suppose you could use a VAWT but I would imagine the efficiency would be less?
No doubt someone's probably tried it... somewhere.

[dnix71]

This would be a nice deal as long as you always want to go downwind. I've been sailing with my father and a neighbor in Tampa Bay and the Gulf, so I understand tacking.

Tacking in a car isn't real world, though, unless you pave over everything first. You can go upwind in a sailboat by tacking, but it's slow and you have to learn to duck a lot or you will "boomed" overboard when coming about.