Dauntless
100 TW
Hillhater said:Mmmm ! Arrhhhhh....Bacon
Homer (Simpson)
Was that my copy of Novum Organum you just ate?
Hillhater said:Mmmm ! Arrhhhhh....Bacon
Homer (Simpson)
endlessplane said:That would be indeed impossible, if the two molecules where moving in the same direction, so that everything happens in one dimension only.doctorGONZO said:explain how an air molecule can outrun a sail molecule and strike it and transfer momentum into it if the sail molecule is a priori moving 2.5 times as fast as the prevailing wind and its molecules.
But here the sail/propeller molecules are not moving directly downwind. Their velocity vectors have a component perpendicular to the true wind, so it is a two dimensional problem and you have to use vectors to describe the collision. See the vector diagram I posted above, and this animation which visualizes the deflection of the air-molecules (strongly simplified) from different reference frames:
[youtube]63hvQABLOaE[/youtube]
Here the same thing for the propeller cart:
[youtube]FqJOVHHf6mQ[/youtube]
If you forgot it, you can read it in the OP (that's short for Opening Post. ) ? it's on Page One. (That's page 1).doctorGONZO said:Now, endlessplane, could you help me remember the description of the experiment as it was explained in the OP (that's short for Opening Post. ) ? it's on Page One. (That's page 1).
Yes, the car travels directly downwind. But the car has moving parts, which don't move directly downwind. As shown in the top left picture:doctorGONZO said:"In order for the car to travel directly downwind faster than the wind using only the wind for power,......."
doctorGONZO said:LOL.:lol:
Well, another batch of "believer" posts that are totally unconvincing.
I still dont understand any way that an object can be pushed by a second object that is much slower than the "pushed" one.
There have been so many posts made by "believers" that have been personally insulting and with such a desperate tone that it is very easy to guess that somebody is trying to do a scam.
Insulting my intelligence or veracity accomplishes nothing to explain it to me or anybody else.![]()
doctorGONZO said:LOL.:lol:
Well, another batch of "believer" posts that are totally unconvincing.
I still dont understand any way that an object can be pushed by a second object that is much slower than the "pushed" one.
There have been so many posts made by "believers" that have been personally insulting and with such a desperate tone that it is very easy. . . . .(ZZZZZZZZZZZZZZZZZZZZZZ. . . .)
Insulting my intelligence or veracity accomplishes nothing to explain it to me or anybody else.![]()
Spose I am messing round in your own tomato patch and you catch sight of me. Being a confessed coward, I take off running. Being a Fast Old Boy, I can run 25 MPH. You are really pissed at me getting your own tomatoes and you lose your temper and pick up your 44. You 44 has bad bullets and can shoot at only 10 MPH muzzle velocity.
For the math-challenged, 25 MPH is 2.5 times 10 MPH.
How is you bullet, going at 10 MPH, going to ever catch up to me, transfer momentum to my sad body, and throw me on my face on the ground?
Dauntless said:doctorGONZO said:LOL.:lol:
Well, another batch of "believer" posts that are totally unconvincing.
They're supposed to convince you of WHAT? That you're not funny arguing over nothing?
I still dont understand any way that an object can be pushed by a second object that is much slower than the "pushed" one.
Watch the ruler video again. Where the car moves faster than dat ruler what pushes. Are you going to believe your own eyes? You are doing your damndest to deliberately NOT get it, and YOU are the one flinging the insults.
There have been so many posts made by "believers" that have been personally insulting and with such a desperate tone that it is very easy. . . . .(ZZZZZZZZZZZZZZZZZZZZZZ. . . .)
Insulting my intelligence or veracity accomplishes nothing to explain it to me or anybody else.![]()
(ZZZZZZZZZZZ SNORK!!) Um, you should be telling yourself that. . . .
Spose I am messing round in your own tomato patch and you catch sight of me. Being a confessed coward, I take off running. Being a Fast Old Boy, I can run 25 MPH. You are really pissed at me getting your own tomatoes and you lose your temper and pick up your 44. You 44 has bad bullets and can shoot at only 10 MPH muzzle velocity.
For the math-challenged, 25 MPH is 2.5 times 10 MPH.
How is you bullet, going at 10 MPH, going to ever catch up to me, transfer momentum to my sad body, and throw me on my face on the ground?
So, for your analogy to WORK, you have to accept that you are running not straight at me, but at a 30 degree angle to run past me. Before you started running you were 18.66 feet from me. I pointed my Dirty Harry weapon straight at you, but once you started I swung it 90 degrees around. When you are 25 feet away from crossing in front of the barrel I fire, the bullet will travel 10 feet in the time it takes you to get it its' path and YOU ARE HIT! (Oooops at a 30 degree angle you start closer than 25 feet from where you cross in front of the gun. Since someone might bring that up.)
That is the analogy they have made to you, yours adapted to befit it. If in fact the bullet didn't kill you or knock you down, imagine it was self propelled, it would continue in the direction it was travelling at 10mph. If you continued in the direction you were travelling as though on rails, propelled only by the bullet which pushes in its' own direction and not yours, you would be going 20mph pushed by a 10mph bullet. I don't have the calculator handy (Library computer doesn't offer it, dadgum it.) or I could give you an angle for the full 25mph. Because the 2 dimensional movement requires a greater distance to be covered by you than by the bullet pushing you, you have to go faster than the bullet. The wind has to continue at the 10mph because there's more wind behind pushing it. I got all this from reading these posts.
So, for your analogy to WORK, you have to accept that you are running not straight at me, but at a 30 degree angle to run past me. Before you started running you were 18.66 feet from me. I pointed my Dirty Harry weapon straight at you, but once you started I swung it 90 degrees around. When you are 25 feet away from crossing in front of the barrel I fire, the bullet will travel 10 feet in the time it takes you to get it its' path and YOU ARE HIT! (Oooops at a 30 degree angle you start closer than 25 feet from where you cross in front of the gun. Since someone might bring that up.)
That is the analogy they have made to you, yours adapted to befit it. If in fact the bullet didn't kill you or knock you down, imagine it was self propelled, it would continue in the direction it was travelling at 10mph. If you continued in the direction you were travelling as though on rails, propelled only by the bullet which pushes in its' own direction and not yours, you would be going 20mph pushed by a 10mph bullet. I don't have the calculator handy (Library computer doesn't offer it, dadgum it.) or I could give you an angle for the full 25mph. Because the 2 dimensional movement requires a greater distance to be covered by you than by the bullet pushing you, you have to go faster than the bullet. The wind has to continue at the 10mph because there's more wind behind pushing it. I got all this from reading these posts.
This is more or less what they've all told you. I think you've already understood it well enough. If you REALLY just want to keep arguing and spitting venom, maybe it's time for you to be banned. (Again?)
endlessplane said:Yes, the car travels directly downwind. But the car has moving parts, which don't move directly downwind. As shown in the top left picture:doctorGONZO said:"In order for the car to travel directly downwind faster than the wind using only the wind for power,......."
![]()
doctorGONZO said:endlessplane said:Yes, the car travels directly downwind. But the car has moving parts, which don't move directly downwind. As shown in the top left picture:
![]()
But thay dont explain SQUAT.
See diagram above. The velocity of the blade (in the ground reference frame) and the force of the air on the blade are at less than 90° to each other. So the air is doing positive work on the blade (transferring energy to it), in accordance with the dot product of force and velocity:doctorGONZO said:"Show me the specific path that a unity of energy takes starting with a molecule of wind and how it winds up moving the car faster than the wind"
Wind is not a force, but a velocity difference. It doesn't make any sense to add a force (thrust) and a velocity (wind).TylerDurden said:The prop produces thrust.
T = thrust
W = wind (force)
d = drag
rr = rolling resistance
gL = gear losses
If: T+W > d+rr+gL, the car moves and increases thrust.
As speed increases, thrust increases, until d+rr+gL = T+W.
This is better stated as: The propeller pushes back the air, which moves relative to the ground. The propeller slows down the air relative to the ground, so it extracts wind energy.TylerDurden said:The thrust pushes against the wind
Is "drag" the aerodynamic drag of the chassis? If yes then you are missing another crucial retarding force. To turn the propeller you need to supply it with a torque, which creates a braking force at the wheels. The key here is to explain why this braking force at the wheels can be less than the propeller thrust. And the answer to that is the difference in the relative velocities between cart/air & cart/ground. This difference is equal to the true wind, and when it's is zero the cart cannot work, because then the propeller thrust is less than the braking force at the wheels needed to turn the propeller.TylerDurden said:d = drag
rr = rolling resistance
gL = gear losses
The cart is designed to use the energy in the shear plane that exists between the air and ground when there is wind. By leveraging one against the other, speed can be gained at the expense of force. To achieve 3 times wind speed, they had to sacrifice at least 2/3 (I suspect closer to 3/4) of the propeller’s thrust to the ground to provide the torque to turn the propeller.
liveforphysics said:Anytime you have a relative difference in energies (airspeed vs the ground in this case, could be a temp difference or elevation difference or chemical potential difference etc etc) you have real energy available for capture and re-use in whatever manner you please, including using it to speed yourself up.
liveforphysics said:If you were cruising in this vehicle traveling downwind at 30mph in a 15mph wind, and you drove onto a super long treadmill moving forward at 30mph (so, zero wheel speed now for your 30mph traveling car), if you had a brake you could apply, you would just continue traveling at 30mph riding on the treadmill, but what would happen if you changed nothing, just drove onto it? (assume zero moment of inertial for all rotational mass for the sake of the exercise, as it would only delay it eventually finding its equilibrium)
No, because it's not an isolated loop, that sustains itself. It has a continuous energy input, from the air that is slowed down relative to the ground.doctorGONZO said:feedback loop is a description of a runaway OU Over Unity scenario.
There is no Over Unity involved here. Just wind energy.doctorGONZO said:Plainly state whether any of these "believers" are claiming or even implying that this 2.5 car thingy is an Over Unity thingy capturing Free Energy. Or, plainly state if any of these "believers" have figured out this thingy in theory and dismiss any possibility of OU Free Energy.
It can. It doesn't use any internally stored energy for propulsion, so it can operate in steady state above windspeed.doctorGONZO said:As configured the car cannot sustain a speed over 1.0.
So the vehicle is geared to go downwind at 2x windspeed. Since on the treadmill the wind relative to surface is -15mph, a symmetrically build vehicle would try to travel -30mph relative to the treadmill belt. Which is 0mph relative to the ground: It would hover on the treadmill.liveforphysics said:This is something fun to think about. If you were cruising in this vehicle traveling downwind at 30mph in a 15mph wind, and you drove onto a super long treadmill moving forward at 30mph (so, zero wheel speed now for your 30mph traveling car), if you had a brake you could apply, you would just continue traveling at 30mph riding on the treadmill, but what would happen if you changed nothing, just drove onto it? (assume zero moment of inertial for all rotational mass for the sake of the exercise, as it would only delay it eventually finding its equilibrium)
liveforphysics said:Gonzo- Have you ever moved faster than the wind was blowing in a vehicle (like maybe every commute)? Did it violate over-unity to do it, or did you just need some energy budget to spend on moving faster than the wind? (energy budget which you could acquire from any source you like, including wind).
This is not like putting a generator in your front wheel to power the motor in your rear wheel and expecting it to power you. This has a real energy source to power it to be able to travel at speed. Anytime you have a relative difference in energies (airspeed vs the ground in this case, could be a temp difference or elevation difference or chemical potential difference etc etc) you have real energy available for capture and re-use in whatever manner you please, including using it to speed yourself up.
I agree the mechanism of function is both counter-intuitive and semi-complex (it still weirds me out a little). That doesn't mean it's impossible to harness energy from the wind/ground speed difference and use that energy to travel at a higher rate. I also know some of the guys who helped build and test this vehicle, it really works, and given more time/budget to further reduce drag/parasitics and/or improve energy capture it could travel at even higher multiples of wind speed.
This is something fun to think about. If you were cruising in this vehicle traveling downwind at 30mph in a 15mph wind, and you drove onto a super long treadmill moving forward at 30mph (so, zero wheel speed now for your 30mph traveling car), if you had a brake you could apply, you would just continue traveling at 30mph riding on the treadmill, but what would happen if you changed nothing, just drove onto it? (assume zero moment of inertial for all rotational mass for the sake of the exercise, as it would only delay it eventually finding its equilibrium)