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Mess with your minds: A wind powered craft going faster than a tail wind speed.
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electrodacus:

--- Quote from: bdunham7 on December 18, 2021, 09:42:37 pm ---
--- Quote from: electrodacus on December 18, 2021, 09:26:33 pm ---The only way you get that 11W on the output is if you add another power supply in parallel or series with the first one.

--- End quote ---

Yes, that's the principle.  The propeller and the wind are 'in series', so to speak.  If you like bad analogies, you can compare the various 'speed' of the players with voltage.  If the wind and the vehicle are at the same speed you can compare that to a power source and a sink--say a charger and battery--that are both at the same voltage so that no power flows.  But if you add an isolated DC-DC converter across the source and then put its output in series between the source and sink, now power will flow.

So the wheel-to-propeller link can be considered as a sort of boost converter that allows power to go from an original source that is the same or even lower voltage than the sink.

--- End quote ---

I provided this analogy to show that if the only input is the wheel you can not get 11W out of just 5.5W at input.
And to continue with this analogy when vehicle is below wind speed there is extra power available from wind but at wind speed that power available from wind is 0W thus since the example was when vehicle speed = wind speed output of the propeller can not be more than 5.5W input from the wheel thus no acceleration possible. In real world blackbird there is the stored pressure differential energy that provides the power to cover the losses plus extra for acceleration.
So the point I made is that a energy storage device is needed to exceed wind speed directly down wind and that is the pressure differential with you do not understand thus try to avoid.

And to be clear a boost DC-DC converter outputs will be lower power than input and also any boost converter will have energy storage devices either an inductor a capacitor or both.
Alex Eisenhut:

--- Quote from: electrodacus on December 18, 2021, 10:17:02 pm ---
And to be clear a boost DC-DC converter outputs will be lower power than input and also any boost converter will have energy storage devices either an inductor a capacitor or both.

--- End quote ---

What about a DC-DC converter with a solar panel providing 1 watt in sunlight added to the output, and used outside?

What then? How much power do you measure at the input vs the output?

Suppose a 5V to 12V boost converter you can buy on eBay, it's 90% efficient. Power to the input from a USB power pack at 5V with enough current capacity. I added a solar panel and circuitry to add the power to the output. I used it outside in sunlight no clouds with the solar panel pointed at the sun.

I measure 12V at 1A through a resistor. Do you agree this is 12 watts of output power?

Then a 90% efficient supply would need 13.3W, so 2.7A at 5V.

But 1W is coming from the solar panel.

How much current will the supply actually need at 5V?

2.5A? Why? 12W at 90% efficiency = 13.3W needed, MINUS 1W from the panel, 12.3W needed from the 5V supply.

Clear? The *SUN* has added power. Happy?
electrodacus:

--- Quote from: Alex Eisenhut on December 18, 2021, 10:33:51 pm ---
--- Quote from: electrodacus on December 18, 2021, 10:17:02 pm ---
And to be clear a boost DC-DC converter outputs will be lower power than input and also any boost converter will have energy storage devices either an inductor a capacitor or both.

--- End quote ---

What about a DC-DC converter with a solar panel providing 1 watt in sunlight added to the output, and used outside?

What then? How much power do you measure at the input vs the output?

Suppose a 5V to 12V boost converter you can buy on eBay, it's 90% efficient. Power to the input from a USB power pack at 5V with enough current capacity. I added a solar panel and circuitry to add the power to the output. I used it outside in sunlight no clouds with the solar panel pointed at the sun.

I measure 12V at 1A through a resistor. Do you agree this is 12 watts of output power?

Then a 90% efficient supply would need 13.3W, so 2.7A at 5V.

But 1W is coming from the solar panel.

How much current will the supply actually need at 5V?

2.5A? Why? 12W at 90% efficiency = 13.3W needed, MINUS 1W from the panel, 12.3W needed from the 5V supply.

Clear? The *SUN* has added power. Happy?

--- End quote ---

We are drifting in all sort of analogies but to try and answer what happens imagine that vehicle with the solar panel having the solar panels rotate away from the sun as the speed increases. That is what happens to a wind powered vehicle that drives directly downwind.

As for solar panel + boost converter the output of the boost converter will be always lower than 1W if solar panels outputs 1W

Why are you involving a battery ? Have you not mentioned there is no energy storage device or external power source ?


Here are the correct equations for wind power available to a vehicle traveling directly down wind
0.5 * air density * area * (wind speed - vehicle speed)^3    yes this is the correct equation. Notice how you have highest power at low vehicle speed and power drops to zero by the time vehicle speed equals wind speed.




IanB:

--- Quote from: electrodacus on December 18, 2021, 10:44:10 pm ---Here are the correct equations for wind power available to a vehicle traveling directly down wind
0.5 * air density * area * (wind speed - vehicle speed)^3    yes this is the correct equation. Notice how you have highest power at low vehicle speed and power drops to zero by the time vehicle speed equals wind speed.

--- End quote ---

But why is this the correct equation?

Please derive this equation step by step from first principles, stating any assumptions made at each step.
Labrat101:

--- Quote from: electrodacus on December 18, 2021, 06:21:29 pm ---
--- Quote from: Labrat101 on December 18, 2021, 10:18:04 am ---@electrodacus
A Bumblebee can't fly .!!
Same as electrodacus can't  believe a simple
Solution.  That if everyone says the 🌎 is round .
He would argue its flat because my spirit level says so .. :palm:
So if everyone here has proven it does work .
Plus there has been a video showing it works
. There for Bumblebee can fly also faster the tail wind .
Your ideas of what is true and false , was is, and what can . 
  Maybe beyond your comprehension .
  It wouldn't matter if Albert Einstein could tell you that your wrong .
You are living in some sort of self denial.
Get over it and except that it can and does work.

--- End quote ---

Solution is not simple and I never believe anything I need to understand.
All works as shown in tests and is fully described by my theory.
On the other hand the equations you proposed do not predict what happens in real tests.

--- End quote ---
You Quoted ::
  Solution is not simple and I never believe anything I need to understand.   Explain Just ONE thing that YOU do UNDERSTAND   :-DD
On the other hand the equations you proposed do not predict what happens in real tests.  .. What equations do you see in my quote??
   It's Text .. ie   NO numbers. 
Also you quoted this ::
   Luckily there are people that understand all this they just seems to be unwilling to waste time with you (all).
 Maybe all your People you Know . Have all ready been institutionalised and not allowed out to the general public .  :-DD
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