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| Mess with your minds: A wind powered craft going faster than a tail wind speed. |
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| Kleinstein:
The problem with the motor example is that a motor with a given fixed efficency is kind of including an automatic gear box to adjust the torq to the speed. So it does not make sense to consider such an ideallized motor with a gear reduction. So the example just does not make sense. With only one vehichel on one groud the wheels see the same speed and thus in this special case with ideallized motors power is directly proportional to force. So in this special case there is no consequence in confusing power and force - except that you can't transfer this to other cases. So the example is a bad example. Things get different if the 2 wheels are on different grounds moving relative to each other. |
| electrodacus:
--- Quote from: Kleinstein on September 18, 2021, 08:57:32 pm ---The problem with the motor example is that a motor with a given fixed efficency is kind of including an automatic gear box to adjust the torq to the speed. So it does not make sense to consider such an ideallized motor with a gear reduction. So the example just does not make sense. With only one vehichel on one groud the wheels see the same speed and thus in this special case with ideallized motors power is directly proportional to force. So in this special case there is no consequence in confusing power and force - except that you can't transfer this to other cases. So the example is a bad example. Things get different if the 2 wheels are on different grounds moving relative to each other. --- End quote --- Not sure what you try to do here. Let me modify the example to see if that makes things better for you. Motor is the same and has 100W available at the motor axle. For back wheel the motors is connected trough a 0.5:1 gear ratio with 90% efficiency so you have 90W available at the wheel On the front wheel motor is connected trough a 1:1 gear ratio with say 95% efficiency so you have 95W available at the wheel. Do you even care what gear ratio was used to know what direction will the vehicle move ? |
| PlainName:
--- Quote ---Vehicle is powered by the paper (hope you agree with that) --- End quote --- Yes! --- Quote --- so it can move forever --- End quote --- YES!!! --- Quote ---but speed of the paper will always be higher than average speed of the vehicle --- End quote --- Irrelevant and meaningless. Does the vehicle move left to right? Yes! Does it move right to left? No! That's it - how, when, with what, at what speed, anything else is not relevant and just adding to the noise. |
| electrodacus:
--- Quote from: dunkemhigh on September 18, 2021, 09:09:31 pm ---Irrelevant and meaningless. Does the vehicle move left to right? Yes! Does it move right to left? No! That's it - how, when, with what, at what speed, anything else is not relevant and just adding to the noise. --- End quote --- It moves from left to right because there is energy storage and that was not considered in the theoretical problem. Remove the energy storage and vehicle will not be able to move from left to right. Or maybe simpler to do remove the ability of front wheel to slip and again vehicle will not be able to move from left to right. This represents a vehicle with a wind turbine driving against the wind direction at about 0.5x the wind speed so no traveling indefinitely above wind speed as the original claim is for blackbird. So this video proves my point that using energy storage allows the vehicle to exceed wind speed (paper speed) for a limited amount of time proportional with the amount of energy storage capacity available but average speed is way below wind speed. Your claim is that vehicle can maintain above wind speed indefinitely and that is not shown at all in my video or any other experiment I'm aware of since that will not be possible. |
| PlainName:
--- Quote ---It moves from left to right because there is energy storage --- End quote --- Whatever, it's irrelevant. It wouldn't be if... --- Quote --- for a limited amount of time proportional with the amount of energy storage capacity available --- End quote --- but that's not what's happening. It works indefinitely. --- Quote ---This represents a vehicle with a wind turbine driving against the wind direction at about 0.5x --- End quote --- Irrelevant. It was impossible in this experiment for the vehicle to move left to right. You said that yourself, based on your thinking (and knowledge that none of the rest of us have). Forget the wind, this experiment shows that your thinking was not appropriate and the model does something you said was impossible. So, now this is possible what else that you've decided isn't might be after all? Clearly, somewhere along the way your thinking has jumped the rails. Doesn't matter if it's this energy storage thing you bang on about or something else - you didn't have a grip on this aspect. Maybe you should review your preconceptions and figure out what you missed. |
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