General > General Technical Chat

Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??

<< < (75/148) > >>

PlainName:

--- Quote ---I provide the one that is correct many times.
--- End quote ---

No, you haven't. You keep posting the wrong one. Where in that does it account for the propeller or drive to it? Are you saying they don't exist? They are the thing that makes this different from a sailboat, and yet your equation ignores them completely.

It is the wrong one. Really.

electrodacus:

--- Quote from: dunkemhigh on July 10, 2022, 05:40:10 pm ---No, you haven't. You keep posting the wrong one. Where in that does it account for the propeller or drive to it? Are you saying they don't exist? They are the thing that makes this different from a sailboat, and yet your equation ignores them completely.

It is the wrong one. Really.

--- End quote ---

What has the design of the vehicle to do with available wind power ? Other the equivalent area that interacts with air there is no aspect of the vehicle that will influence the amount of wind power available to vehicle.
If you have had the back wheels generating energy for the front wheel. Will you have considered that as important in any way or make any sense ?
The main difference between the propeller being used as propulsion instead of the front wheel is the fact that propeller is also a large capacity energy storage device due to pressure differential that it creates.
That stored energy is a separate matter that is calculated separately as it has nothing to do with the question I posted and that is the available wind power relative to vehicle speed.

I know you have a feeling that propeller is important but it is because it is an energy storage device not his role as a propulsion device.
For example if you replace air with a non compressible fluid like water then the propeller is exactly like the front wheel no significant energy storage just good for propulsion and in that case the vehicle could not exceed wind speed directly downwind as there will not have been an energy storage device to help with that.
Same could be done if you add an energy storage device between the generator wheels and say a motor wheel in the front like say adding a capacitor or battery in between the two or even a flywheel as this things will be the equivalent of the compressible fluid.

So question is just for available wind power vs vehicle speed and that is the same for any vehicle design.  You just noticed this particular vehicle design exceeds wind speed and concluded that it is magic instead of knowing magic is not real and you need to look for an energy storage device as that is the only thing allowing a wind only powered vehicle to exceed wind speed directly downwind.

gnuarm:
The car is going down wind.  The wheels on the car are connected to a belt so the top side moves backwards, opposite the direction of travel of the car. 

There are sails attached to the belt.  When the car moves forward, the belt moves backwards and the sails with it.  Since the gearing is 1:1, the sails actually stand still as the car moves under them. 

I only want to consider the sails on the top side, so when not on the top side, a mechanism collapses the sails to no size, so they do not interact with the wind. 

When the wind pushes on the sails, it will push on the car as a whole.  The car will move forward.  The belt is geared to the wheels, so moves backwards wrt the car, but stationary wrt the ground, just like the sail.  The wind speed blowing on the sail is always the same, no matter how fast the car moves.  So the available power from the wind is always the same according to YOUR formula. 

The result is the car will be propelled down wind, at a speed determined only by the various power losses vs. the wind power, otherwise having nothing to do with the wind speed.  In other words, the car can move faster than the wind, with no other theoretical limitations than the power in the wind vs. the frictional losses.

If you don't like the gearing that leaves the belt stationary, change it to 4:3 gearing so the belt moves backwards at 3/4 speed of the car moving forward.  Then the wind relative speed of the sail does not drop to zero until the car is moving at 4 times the speed of the wind.  So at some speed, there will be equilibrium between the wind power and the losses in the car.  For that speed to be greater than the wind speed, only requires practical design considerations in limiting the losses.

PlainName:

--- Quote ---I know you have a feeling that propeller is important but it is because it is an energy storage device not his role as a propulsion device.
--- End quote ---

It is no more an energy storage device than a set of tyres are.

Your closed mind prevents you from seeing how it works. I think we are all resigned to that now, but you keep spouting all this wrong stuff and that needs to be corrected or it gets perpetuated as fact (on the basis that no-one disputes it).

electrodacus:

--- Quote from: gnuarm on July 10, 2022, 06:04:21 pm ---The car is going down wind.  The wheels on the car are connected to a belt so the top side moves backwards, opposite the direction of travel of the car. 

There are sails attached to the belt.  When the car moves forward, the belt moves backwards and the sails with it.  Since the gearing is 1:1, the sails actually stand still as the car moves under them. 

I only want to consider the sails on the top side, so when not on the top side, a mechanism collapses the sails to no size, so they do not interact with the wind. 

When the wind pushes on the sails, it will push on the car as a whole.  The car will move forward.  The belt is geared to the wheels, so moves backwards wrt the car, but stationary wrt the ground, just like the sail.  The wind speed blowing on the sail is always the same, no matter how fast the car moves.  So the available power from the wind is always the same according to YOUR formula. 

The result is the car will be propelled down wind, at a speed determined only by the various power losses vs. the wind power, otherwise having nothing to do with the wind speed.  In other words, the car can move faster than the wind, with no other theoretical limitations than the power in the wind vs. the frictional losses.

If you don't like the gearing that leaves the belt stationary, change it to 4:3 gearing so the belt moves backwards at 3/4 speed of the car moving forward.  Then the wind relative speed of the sail does not drop to zero until the car is moving at 4 times the speed of the wind.  So at some speed, there will be equilibrium between the wind power and the losses in the car.  For that speed to be greater than the wind speed, only requires practical design considerations in limiting the losses.

--- End quote ---

I do not not think you fully understand how the vehicle you describe will work.
Seems like what you just did was replace the axial propeller with a savonius type design

Forget about air and wind and imagine there is a automatic gun shutting 1.2kg balls leaving exactly 1m distance between them at say 6m/s relative to ground so that means each second your vehicle can be hit by six 1.2kg balls traveling at 6m/s

Now one of this balls hits the sail that you mentioned and so vehicle can gain that kinetic energy.

Say your vehicle was stationary first ball hits one of those sails. What happens to the vehicle and the sail relative to the ground ? What direction do they move relative to ground ?
Since you say vehicle is direct down wind the vehicle will move in the same direction the ball was moving and so will the sail even if you you seome gear ratio so that sail moves more than the vehicle or the other way around both sail and vehicle will need to move in the same direction relative to ground.

Only if you are talking about a direct upwind vehicle you can say the sail will move in the opposite direction to vehicle direction.

Navigation

[0] Message Index

[#] Next page

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod