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| Mess with your minds: A wind powered craft going faster than a tail wind speed. |
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| IanB:
--- Quote from: Alex Eisenhut on December 25, 2021, 09:53:37 pm ---Do you understand 2+2? Then why don't you understand 2 - (-2)? --- End quote --- This is the problem. I made a post earlier, where I asserted something to the effect that two plus two equals four. electrodacus immediately responded by quoting that post and asking if I therefore agreed that two plus two does not equal four? The guy is being vexatious, contrary, and nonsensical. He is playing games with everyone. There is no point trying to educate the guy with logic or rational arguments, because he is not trying to learn. He is just winding everyone up to see how long he can keep the thread going. If you even get close to showing how a vehicle can sail downwind faster than the wind, as was happening a few posts back, electrodacus immediately changes the subject, or brings in something irrelevant to divert the thread. |
| PlainName:
--- Quote from: electrodacus on December 25, 2021, 06:57:33 pm --- --- Quote from: dunkemhigh on December 25, 2021, 10:11:00 am --- --- Quote from: electrodacus on December 25, 2021, 12:57:45 am --- --- Quote from: dunkemhigh on December 25, 2021, 12:11:34 am ---No, the battery is still driving the motor. It is simply a combination of 1 and 2: wind blowing in the sail, sail being moved along the vehicle. Do you agree the vehicle ground speed would be close to 3m/s? --- End quote --- Yes but this just proves my point that an energy storage device is needed to exceed wind speed. --- End quote --- OK, so now we go back to scenario 2 and replace the moving sail with a static propeller. Recall that: * There is no wind * The propeller is powered by a battery If the speed of the propeller wash is 1m/s, do you agree that the vehicle will move forward at around 1m/s? --- End quote --- Replacing the moving sail with a propeller will not be the same thing if the propeller is not powered by something. And since you do not have a battery and you do not accept there is an energy storage device (pressure differential) then there is nothing that can power the propeller other than the kinetic energy of the vehicle but taking energy from that will result in reduced vehicle speed. So propeller will still rotate but slower and slower same thing that actually happens after the vehicle used all the pressure differential and vehicle starts to slow down. --- End quote --- Mate, why did you create a strawman? Well, obviously, it was to knock him down but, really, it's so blatant. You even quoted me where I said: --- Quote ---OK, so now we go back to scenario 2 and replace the moving sail with a static propeller. Recall that: * There is no wind * The propeller is powered by a battery --- End quote --- Can you grasp that? The propeller is using B.A.T.T.E.R.Y. power to turn, so the rest of your post knocking down your strawman is completely irrelevant. So, once again and PLEASE don't jump ahead, make things up or change the subject: With a propeller fixed in position, powered solely by battery and with no wind, if the prop wash is thrust back at 1m/s, do you NOW agree that the vehicle will move forward at around 1m/s? Also, please bear in mind that this actual experiment is carried out across the world at all times of day an night, so if you still disagree I will be expecting an extraordinary explanation as to why. |
| cdev:
Its the total power that matters I wouldthink. A strong wind can drive a turbine very fast, and then something like an automatic transmission might be used to propel a small payload very fast. Suppose it was running a generator and you were using that to power an eectric motor and wheels, its quite possible. There is even a kind of boat that drives a cylindrical vertical rotary shaft made of two offset cylinders acting as a wind turbine. These boats are able to propel themselves in any direction, just like a motor boat could, as long as the wind is blowing in any direction. (Does anybody know the name for this invention, which is at least 100 yrs old. --- Quote from: Rerouter on May 30, 2021, 01:01:07 am ---Against the wind already would be possible with a craft like this, as long as the drag force of the blades is higher than the craft, it would be working like a windmill, --- End quote --- |
| electrodacus:
--- Quote from: Alex Eisenhut on December 25, 2021, 09:53:37 pm ---The thing you seem to be ignoring is that the propeller is part of the vehicle and is blowing its own wind backwards. The effective wind speed is both. Do you understand 2+2? Then why don't you understand 2 - (-2)? --- End quote --- What powers the propeller when vehicle is above wind speed ? It is a simple question for with you have no answer. |
| electrodacus:
--- Quote from: dunkemhigh on December 25, 2021, 10:45:39 pm --- Mate, why did you create a strawman? Well, obviously, it was to knock him down but, really, it's so blatant. You even quoted me where I said: --- Quote ---OK, so now we go back to scenario 2 and replace the moving sail with a static propeller. Recall that: * There is no wind * The propeller is powered by a battery --- End quote --- Can you grasp that? The propeller is using B.A.T.T.E.R.Y. power to turn, so the rest of your post knocking down your strawman is completely irrelevant. So, once again and PLEASE don't jump ahead, make things up or change the subject: With a propeller fixed in position, powered solely by battery and with no wind, if the prop wash is thrust back at 1m/s, do you NOW agree that the vehicle will move forward at around 1m/s? Also, please bear in mind that this actual experiment is carried out across the world at all times of day an night, so if you still disagree I will be expecting an extraordinary explanation as to why. --- End quote --- What are you even talking about ? Why include a battery in the equation when you claim no energy storage is available to vehicle. Maybe you need to add the battery as else you have no explanation? For the vehicle to maintain 3m/s with a 2m/s tail wind the battery will need to provide enough power to cover all frictional losses. Now please explain what will replace your fictional battery in the real blackbird? |
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