I don't understand how this car works.

@DrewDad,

Yes DD -- thanks for the correction. Slip of the (wrong) finger. 27.5 ft/sec it is.

(back after lunch)

JB

@ThinAirDesigns,

I figured you just wanted to make sure I was paying attention.

Just bookmarking this to keep up on it.

Rather a cool concept.

The wind is always providing energy relative to the ground. The problem is how much energy can be used at any given time by the moving car.

Ignoring the sail aspect -

Energy provided by wind turns wheels.
Energy turning wheels powers propeller. (Some energy is lost to friction)
Propeller pushes back against wind to cause speed to increase. (More energy is lost to friction.)

Basically increasing the friction to drive the propeller forces the wind to do more work to keep the car at speed and then you get the extra speed by pushing back against the wind. There is clearly a point at which you lose any advantage but you are capturing more of the wind energy and directing it to a prop. But the point to remember is the wind is ALWAYS adding energy to the system. It's just the added energy is being used more efficiently.

A car pushed by the wind can capture energy. An electrical generator attached to the wheels would increase friction but no one would argue that there could be no electrical generation if the car was moving at almost the speed of the wind since the wind is always adding energy and pushing the car. Then no one would argue that a propeller can't propel a car faster than the air is moving if the propeller was powered by an electrical motor. All this does is remove the electrical generator and motor from the system to make the car move faster than the air. The system loses energy which is why there is an upward speed boundary but it has a constant input from the wind.

1 Reply

@Cycloptichorn,

Quote:

Not that you guys really care about skeptics, but hey. This is a big deal! You just don't see modern physics experiments on the macro level like this.

Lord they care just look at the efforts that thinaridesign is going on this one website and then mult. it by the many such newsgroups/websites you can find by
googling the subject.

Second there will for one reason or another be no detail check of their claimed
and that is my prediction.

Some condition or agreement for such a test will fall through time after time as that is the pattern for all such claims in the past.

If this was not a hoax they would be not be spending so must effort on waving in the air physics and moving heaven and hell to have the hardest most control test done in front of everyone who think like I do this is a hoax.

The only question I can not as yet figure out is what the hell they are getting out of this claim.

Is a group doing research not on physics but on how hard it is to sell such hoaxes on the internet?

1 Reply

@BillRM,

Quote:

Second there will for one reason or another be no detail check of their claimed and that is my prediction.

As I said before - when you are proven wrong, are you going to come back and admit it like a man?

Cycloptichorn

1 Reply

@Cycloptichorn,

I would ask you the same question however I question if they will ever allow a control test of their device/wind car.

When others build such winds cars and they fail the test it will because the cars that fail was not build correctly in some manner and just as soon as their lawyers allow or the test conditions or the place of the test or a blue moon in right they will show us all how it is done.

This is an old old story indeed

So if no tightly control tests are done in the next year will you be a man and tell me that I was right to believe in Newton's laws and you was wrong to fall for a hoax?

2 Replies

@parados,

parados wrote:

But the point to remember is the wind is ALWAYS adding energy to the system. It's just the added energy is being used more efficiently.

Yes. I was discussing this with my father the other day, and after much bashing of ideas around, this is the way he described it as well. He described it as a more efficient use of the available energy from the wind.

0 Replies

@BillRM,

BillRM wrote:

I would ask you the same question however I question if they will ever allow a control test of their device/wind car.

When others build such winds cars and they fail the test it will because the cars that fail was not build correctly in some manner and just as soon as their lawyers allow or the test conditions or the place of the test or a blue moon in right they will show us all how it is done.

This is an old old story indeed

So if no tightly control tests are done in the next year will you be a man and tell me that I was right to believe in Newton's laws and you was wrong to fall for a hoax?

Yes, I will. Will you? You didn't answer the question.

However, I don't believe it is a hoax, primarily because the physics behind it is indeed sound. Only you seem unable to grasp the conceptual physics here, Bill.

Cycloptichorn

0 Replies

@BillRM,

BillRM wrote:

I question if they will ever allow a control test of their device/wind car.

We've just finalized NALSA (nalsa.org) testing to occur the week surrounding the 4th of July weekend. Weather permitting it will be held on the runways of the NASA Ames Research Center. Second site (again weather dependent) will be the El Mirage dry lakebed in SoCal.

You're wrong on all counts.

JB

1 Reply

@DrewDad,

DrewDad wrote:

I figured you just wanted to make sure I was paying attention.

I never need an excuse to screw up. :-)

So, currently we agree that for a 100% efficient propeller to produce 10lbs of thrust traveling through the air at 27.5 ft/sec would require an input of 1/2HP.

Would you agree that it takes this exact same amount of power to achieve this no matter which way the "wind" is blowing? -- In other words, it matters not which direction or what speed the ground is going by below the propeller ... it still takes 1/2HP?

Perhaps the ground is going by below at zero ft/sec. Perhaps the ground is going by at one thousand ft/sec. All irrelevent to the power calculation of 1/2HP.

Agree?

JB

1 Reply

@ThinAirDesigns,

Yes. Assuming level flight, constant indicated airspeed of 27.5 ft/sec, 10 lbs of thrust, the propeller is generating 1/2 hp and power output is independent of ground speed.

To be at steady state, you also have to be developing 10 lbs of drag in the opposite direction.

Agree?

1 Reply

@DrewDad,

DrewDad wrote:

To be at steady state, you also have to be developing 10 lbs of drag in the opposite direction.

Agree?

Super Duper -- glad you asked that because that's exactly where I was headed next.

With our thrust we can pull on *anything* we want as long as it produces a resistive force of 10lbs. We can pull a drogue chute, a banner, an airplane chassis ... or perhaps a generator rolling along the ground providing 10lbs of resistance.

All good?

JB

0 Replies

How about we pick that last option from above DD.

Let's bring our 100% efficient propeller with it's string off the back pulling with 10lbs of force and moving 27.5 ft/sec while sucking up 1/2HP down to a level just above the ground.

Let's suppose that there is a 55 ft/sec wind over the ground and we align the path of our propeller so it is going directly downwind

Let's tie our string off to a small chassis with a wheel driving a small electrical generator. Let's assume just for the moment that like our prop, our generator is 100% efficient and that our chassis is perfectly dragless (we'll get to all that I assure you).

With a string pulling on our generator with 10lbs of force and moving the generator at 55 ft/sec, how many HP can we pull out of that generator?

JB

1 Reply

Here is an interesting analysis (and some penance) from someone who originally called the idea a hoax committed by "bozos" and then completely changed his mind (and apologized profusely) as he realized he was wrong.

http://scienceblogs.com/goodmath/2008/12/the_real_bozo_attempts_to_aton.php

He provides an interesting static analysis with pictures where he works out the math.

http://scienceblogs.com/goodmath/rigid-wheels.png

He then analyzes the propeller driven cart and comes up with as clear an analysis as you can get. I could outline the argument here... but why not just read it at the link.

http://scienceblogs.com/goodmath/propellor.png

You will note that this is simply Newton's laws doing what Newton's laws do. There is no law of science being broken.

He explains as clearly as anyone can that thrust = wind_thrust + propeller_thrust. If you don't understand the Physics after this explanation, I don't think you ever will.

1 Reply

Mark Chu-Carroll (above link) knows how to man up and give a serious apology. Of course we deserved it after him calling us Bozos and frauds.

We appreciated it and have told him so personally.

JB

0 Replies

ThinAirDesigns wrote:

How about we pick that last option from above DD.

Let's bring our 100% efficient propeller with it's string off the back pulling with 10lbs of force and moving 27.5 ft/sec while sucking up 1/2HP down to a level just above the ground.

Let's suppose that there is a 55 ft/sec wind over the ground and we align the path of our propeller so it is going directly downwind

Let's tie our string off to a small chassis with a wheel driving a small electrical generator. Let's assume just for the moment that like our prop, our generator is 100% efficient and that our chassis is perfectly dragless (we'll get to all that I assure you).

With a string pulling on our generator with 10lbs of force and moving the generator at 55 ft/sec, how many HP can we pull out of that generator?

JB

DrewDad -- I apologize as I have placed a number wrong again above.

Please replace the 55 ft/sec wind in the third paragraph with a 27.5 ft/sec wind. This will make the 55 ft/sec over the ground speed in the 5th paragraph correct. I caught my mistake too late to edit it.

Thanks
JB

0 Replies

@ThinAirDesigns,

Why do you need the tailwind in this example? You've already got your 10 lbs of thrust.

1 Reply

@ThinAirDesigns,

Quote:

We've just finalized NALSA (nalsa.org) testing to occur the week surrounding the 4th of July weekend. Weather permitting it will be held on the runways of the NASA Ames Research Center. Second site (again weather dependent) will be the El Mirage dry lakebed in SoCal.

You're wrong on all counts

We will see if testing control by a respected completely independent group will or will not come off.

All testings/measurings/video taping out of your group control and hands along with a complete examination of the car down to it frame work also done by this independent group.

After all it would not be the first time that a complex perpetual motion device have been found to have a power source such as a tank of compress air hidden within.

So let see if we are going to have that level of testing or not on July 4 or at any other time in the future.

1 Reply

@DrewDad,

DrewDad wrote:

Why do you need the tailwind in this example? You've already got your 10 lbs of thrust.

I think if you do the calcs I suggested it might come clear.

JB

0 Replies

I may not be able to get back to this anymore this evening. Hopefully I'll be able to pick up the conversation again tomorrow.

1 Reply

I don't understand how this car works.

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