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Messages - Alan Fox

1
Offering free and unsought advice (no liability accepted for anyone taking it) from  an outside observer. Perhaps the Democrat organisation could think about alternatives. Maybe look for a candidate for president with fresh ideas, maybe not of retirement age. Asking grass roots for their opinions and take those ideas on board (France's new party organisation, "En Marche" spent time consulting and the result was effective in getting them a huge legislative majority). Concentrate on grassroots funding instead of relying on rich donors who expect payback.  Maybe start  planning for the next presidential election now?
2
Yes, the journalist, Carole Cadwalladr has produced a number of pieces on the subject... More to come!

And I see Robert Mercer has popped up again in a Guardian article on the "Paradise Papers".
3
I'm a UK ex-pat living in France. Brexit and its consequences affect me personally so I've followed the fortunes of some of those closely involved in the referendum process and its aftermath. One such is Nigel Farage who ran a UK political party (UKIP) that was set up largely to promote the UK's exit from the European Union. But Farage then popped up on stage with Donald Trump to support his campaign. I thought it odd at the time. What was the connection, I wondered.

In parallel, I was struck by this odd piece in the Palm Beach Post mentioning one Robert Mercer, a financial backer of the Trump  campaign. It turns out there is a connection between these seemingly unrelated bits of news: Cambridge Analytica.. I read:
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...Alexander Nix, the CEO of Cambridge Analytica, the controversial data firm that helped Trump to power, had contacted Julian Assange to ask him if he wanted "help" with WikiLeaks's stash of stolen emails.

That's the stash of stolen emails that had such a devastating impact on Hillary Clinton in the last months of the campaign. And this story brought WikiLeaks, which the head of the CIA describes as a "hostile intelligence service", directly together with the Trump campaign for which Cambridge Analytica worked. This is an amazing plot twist for the company owned by US billionaire Robert Mercer, which is already the subject of investigations by the House intelligence committee, the Senate intelligence committee, the FBI and, it was announced late on Friday night, the Senate judiciary committee.

I've a suspicion there's more to come.

4
Science / Re: Direct Down Wind Faster Than The Wind
As Brother Daniel writes
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I give you an actual experiment you can do:
Get in an elevator on the ground floor with a RC helicopter. Get the copter hovering at eye level.
Push the UP button for the tenth floor. Do not change any settings on the helicopter.
I have to give you some credit here:  That's actually a decent experiment to do.
Indeed. You could also perform the experiment horizontally with a prop attached to a cart powered by electric motor, say, and see what difference in speed in still air and steady (down) wind.
5
Science / Re: Direct Down Wind Faster Than The Wind


You sure know how to be wrong Heinz, it may be your best skill. The problem is not precisely framed, in that there are some transients, but there is no doubt at all that the point Alan is making is correct, and that your rebuttal is bullshit.
To know this, we need only consider what happens to a powered aircraft turning in rising air. Just like when it is flying straight, upon entering the rising air, it will rise, with no increased engine power. A powered, turning aircraft's wing is doing exactly what the helicopter rotor blade is doing, precisely the principles apply for lift and drag. Indeed, if two aircraft are turning on the same radius at opposite sides of a circle, it even looks the same. You could put a beam between the wing tips and a seat  swiveled in the middle and it would actually BE a helicopter!
So, your own argument is, as usual, so internally inconsistent that you have just proven yourself wrong. Again.

Gliders climb by circling inside thermals. No power at all except from the wind. Thanks, Semper.  :)
6
Science / Re: Direct Down Wind Faster Than The Wind
Well then, you have found a home in the Cargo Cult, because your understanding of physics is every bit as poor as the rest of the cult monkeys.
In level (horizontal) flight, if the airmass moves at 10 m/sec with respect to the ground, an aircraft's ground speed will be changed by 10 m/sec also, because it moves within and respect to, the airmass. One way to understand this is no work is done by the airmass on the aircraft in moving it horizontally. That is Physics 101.
OK, so you agree that an aircraft suspended in an airmass moving at some airspeed will have different groundspeed, depending on how that airmass is moving with respect to the ground.

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But, what you are talking about is a vertical updraft, and in this case, there must be work done on the helicopter to lift it against the force of gravity. There is no justification at all for your assumption that a vertical updraft of 10 m/sec will cause the helicopter to rise at 10 m/sec. A helicopter is not a neutrally buoyant object!
Apologies for my simplistic approach but I can't seem to make it complicated.

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You would need to show that the lifting force, from the rising air mass, on the helicopter is great enough to do work against the force of gravity to lift the helicopter, and there is no way for you to show that without doing the math, which you have not done. You have simple-mindedly and wrongly assumed it to be so.
I guess the question is first, does a helicopter use less power hovering (maintaining a fixed height wrt ground) in an updraft than in still air? I would have thought this was indisputable. If so, an additional force is needed for the acceleration. It seems obvious to me that that force is supplied by the wind.
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In fact, if you were to try and understand how a propeller works, you might understand that the updraft can actually reduce the propeller thrust, as it may result in reverse flow through the disk. It can also cause a more turbulent flow, and work against the rotation of the propeller, all of which reduces thrust.
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As I said, the updraft might have no net effect, or it may increase lift, or it may decrease lift. There is no simple way of knowing without a detailed analysis and probably an experiment.
There's something Sean Carroll  wrote about frames of references (in From Eternity to Here) that is ringing bells for me, I'm away from home so don't have the reference now.
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The reason none of this makes sense to you is simply that you don't know the physics involved, and rather than try to learn, you would rather make stupid assumptions; making you just another brain-dead follower of the cargo cult.
I am not entirely ignorant of physics or math. It's a bit like the difference between playwrights and critics. Are you seriously suggesting that a helicopter will behave erratically in an updraft rather than regularly  and predictably?
7
Science / Re: Direct Down Wind Faster Than The Wind
If you think the outdoor runs were in any sense scientific, you are an idiot, dumbass.
Are you suggesting the Blackbird video is a fake? Seriously?
8
Science / Re: Direct Down Wind Faster Than The Wind
So we built the manned vehicle, worked with NALSA to get them to define a new record category, and we set upwind and downwind records with this thing on the playa.
An achievement you must be and should be rightly proud of. I only came across Blackbird in this thread a few months ago when Heinz  managed initially to reinforce my initial reaction that this was as possible as perpetual motion. The video of Blackbird performing downwind (plus someone pointing out that the propellor was turning against the wind) was what helped me see how wind power could be transferred to cart propulsion.
9
Science / Re: Direct Down Wind Faster Than The Wind

I gave you a detailed answer. The thrust will be lower in the updraft than in still air, and I explained why that is so.

If you think the helicopter will move upwards at 10 m/s with the wind, you are wrong.
I do think the helicopter will rise in a rising air current and your explanation as to why you disagree makes no sense.

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It may stay where it is, it may descend or it may rise depending on the difference between the reduction in thrust and the increased aerodynamic force.
Nonsense. the helicopter will rise in rising air, stay at the position (relative to the building) in still air* and sink if the air current is descending.

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If you think you can say what will happen, you are already wrong.

And, since this has nothing to do with the cart, that is the last time I respond to you.
Ah, but it does. Element 2 is to rotate 90 degrees, the building becomes a salt flat and I substitute a modified Blackbird for the helicopter.

ETA*
10
Science / Re: Direct Down Wind Faster Than The Wind
You seem to be conflating two things in your question; one, the aerodynamic force on an object caught in an updraft and two, the thrust from the rotating blades.

These two things are not the same.

Any object, whether it be a helicopter or a sack of potatoes, caught in an updraft will have a lifting force on it from the wind.

How that updraft affects the thrust from the rotating blades is entirely another matter; it will act to lower the thrust, not raise it. To understand this, you must first understand what propeller thrust is. Propeller thrust is a force and like any force it is equal to mass x acceleration. The rotating blades accelerate a mass of air through the disk of the propeller. If there is a reverse air flow, such as an updraft for a helicopter or a tailwind for an airplane, the air mass that can be accelerated through the disk will be reduced, reducing the thrust. There are other reasons why the thrust will be reduced, including a more turbulent flow and a tendency to turbine the propeller.

Depending on whether or not the wind force on the helicopter is greater than the loss of thrust, the power may need to be increased to hold position, not decreased as you think. It is not as simple as you seem to think! Generally, a tailwind will decrease propeller thrust.

I just asked a simple question.  Let me try to be clearer. Imagine a tall building and you are looking out from halfway up at the helicopter hovering outside the window and the air is perfectly still.  The skill of the pilot is such that you can maintain eye contact! It's a thought experiment so let God now switch on a steady vertically upward current of air at 10 m/s. The pilot makes no adjustment to the throttle and the helicopter motor power stays constant. What happens next? I suggest the helicopter will accelerate and reach an upward velocity with respect to you of 10 m/s. It's not a trap. If you don't agree I'd like to know why. Brother Daniel seems to agree with me.
11
Science / Re: Direct Down Wind Faster Than The Wind
To be fair to you, IF you can show how your helicopter scenario is relevant, I will reconsider discussing it.

Just seen this (I'm a sporadic visitor here) so OK. It might help if I tell you that the way I arrived at my current position did not involve carts [on treadmills]*. There are just three elements to it and the first is that I maintain that a helicopter hovering in still air will require a certain input of power from the engine. The same helicopter hovering in a strong, steady updraft will require less power to maintain its position. And I suggest the source of the power replacing that of the motor in the updraft scenario is the wind. If you agree, I'll move to my second element. If you disagree, I'd be curious to know why.

ETA*
12
Science / Re: Direct Down Wind Faster Than The Wind
Well, I'm only a very occasional poster here so apologies for contributing to a derail.  I'm happy to continue a discussion with Heinz in the appropriate thread or start one if that's the etiquette.  If there's no interest, perhaps not even from Heinz., no problem.

The last time we interacted, you did not demonstrate any ability in Physics at all and you freely admitted you cannot "do the math". So, what do you think you can contribute this time around?
Quite simply, I don't think it requires other than a basic understanding of Newtonian physics and no math to arrive at the possibility of travel downwind faster than the wind.

Even Newtonian Physics involves some math, which you were unwilling or unable to do.

If you'd allow me a little rope we could see if that works.
Sure. I will allow you enough rope to hang yourself.

First do you agree that a helicopter in an updraft requires less power to maintain itself in a hover than in still air? If you disagree, then any further input from me would indeed be a waste of time.

Any further input from you on this point would indeed be a waste of time as your question is not relevant to something going faster than the wind POWERED BY THE WIND directly downwind, which a helicopter is not.


Remember I walked into the old threads completely innocent of the idea and experiments and my first reaction was it was a hoax.  You're right that knowing Pingu was an important element in persuading me to make an effort to understand but I got there myself in the end.

Cut the crap. You were led by the nose into this by Pingu and you dared not come to any conclusion that was not in agreement with hers, regardless of what you supposedly understand about Physics.


So!

Do you agree about the helicopter? I you disagree, there's no more to be said.

Until you show how this is in any way related to the wind-powered cart, there is no point in discussing it and no loss if you get lost.

Fair enough.
13
Science / Re: Direct Down Wind Faster Than The Wind
Well, I'm only a very occasional poster here so apologies for contributing to a derail.  I'm happy to continue a discussion with Heinz in the appropriate thread or start one if that's the etiquette.  If there's no interest, perhaps not even from Heinz., no problem.

The last time we interacted, you did not demonstrate any ability in Physics at all and you freely admitted you cannot "do the math". So, what do you think you can contribute this time around?
Quite simply, I don't think it requires other than a basic understanding of Newtonian physics and no math to arrive at the possibility of travel downwind faster than the wind.

Even Newtonian Physics involves some math, which you were unwilling or unable to do.

If you'd allow me a little rope we could see if that works.
Sure. I will allow you enough rope to hang yourself.

First do you agree that a helicopter in an updraft requires less power to maintain itself in a hover than in still air? If you disagree, then any further input from me would indeed be a waste of time.

Any further input from you on this point would indeed be a waste of time as your question is not relevant to something going faster than the wind POWERED BY THE WIND directly downwind, which a helicopter is not.


Remember I walked into the old threads completely innocent of the idea and experiments and my first reaction was it was a hoax.  You're right that knowing Pingu was an important element in persuading me to make an effort to understand but I got there myself in the end.

Cut the crap. You were led by the nose into this by Pingu and you dared not come to any conclusion that was not in agreement with hers, regardless of what you supposedly understand about Physics.


So!

Do you agree about the helicopter? I you disagree, there's no more to be said.
14
Science / Re: Direct Down Wind Faster Than The Wind
Well, I'm only a very occasional poster here so apologies for contributing to a derail.  I'm happy to continue a discussion with Heinz in the appropriate thread or start one if that's the etiquette.  If there's no interest, perhaps not even from Heinz., no problem.

The last time we interacted, you did not demonstrate any ability in Physics at all and you freely admitted you cannot "do the math". So, what do you think you can contribute this time around?
Quite simply, I don't think it requires other than a basic understanding of Newtonian physics and no math to arrive at the possibility of travel downwind faster than the wind.

If you'd allow me a little rope we could see if that works. First do you agree that a helicopter in an updraft requires less power to maintain itself in a hover than in still air? If you disagree, then any further input from me would indeed be a waste of time.

Remember I walked into the old threads completely innocent of the idea and experiments and my first reaction was it was a hoax.  You're right that knowing Pingu was an important element in persuading me to make an effort to understand but I got there myself in the end.
15
Science / Re: Direct Down Wind Faster Than The Wind
Well, I'm only a very occasional poster here so apologies for contributing to a derail.  I'm happy to continue a discussion with Heinz in the appropriate thread or start one if that's the etiquette.  If there's no interest, perhaps not even from Heinz., no problem.
16
Science / Re: Direct Down Wind Faster Than The Wind
1) You never could place a value of thrust on my diagram that is greater than the braking force, without violating COE.
I could and (IIRC) I did.  The trouble is that you don't know what COE means.
HA HA, you have to say (iirc) because you know damn well you didn't and couldn't.


Quote from: Heinz
2) You never could tell me, in what respected peer reviewed journal was anything published about ddwfttw?
Don't know, don't care.
Quote from: Heinz
3) In response to (2) you created your own crackpot version of peer review, that is, reviewed by a cargo cult on the internet!
Given your general lack of comprehension (of anything), it shouldn't be surprising to me that you'd misrepresent my point about peer review like this.

Bullshit. You know damn well that nothing on ddwfttw has ever been published in any respected peer reviewed journal. That's why you had to piss on the peer review process and create your own crackpot internet forum version of it. You really are dishonest as well as physics-challenged. :yes:

When I cornered you with math, your only escape was to proclaim "there's a lot of energy in that ground" :stopper:  HA HA HA!

Ground energy = Frame energy = MAGIC

Scenario one. Helicopter hovers in still air. Scenario two. Helicopter hovers in strong updraft. Do you agree the power required to maintain the hover is less in the strong updraft?

ETA punctuation
17
Science / Re: Direct Down Wind Faster Than The Wind
A basic physics thread may be a good idea, but I don't think Heinz is interested in actually learning any of it.

He was a good foil for me learning something!
18
Introductions / Re: Heinz is Back
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Or could it be, that they just simply found themselves wading in a seemingly bottomless pit of boredom... and when they finally reach their lowest level, they decide to log-in at TalkRational.org
That's a perfect fit for me!

Will Heinz be resuming his spirited rebuttal of Faster-than-the-wind-downwind wind-powered vehicles?
19
A recent paper regarding glacial melting in Antarctica.
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If the wilder excesses of the GCM's with their demonstrated poor levels of predictive skill for whatever reasons are taken away it is interesting to have a look at what can be expected if things proceed along the current real climate trajectory without the putative 'runaway warming' which is not observed.
Well, indeed. Observation and measurement should reinforce or weaken our reliance on particular climate models.

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Danish Meteorological Institute claim ~ - 200 Gt/yr surface mass balance over that last decade for the Greenland ice sheet.  That is, 200 billion tonnes of ice lost every year.  As a side issue unrelated to sea level it's worth noting that over the same period Arctic Ocean sea ice cover has also been mostly declining.
Funny you mention Denmark - a country engaged in a Pascal wager with renewable energy.

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NASA claim between 112 and 82 billion tons * of ice gained per year on Antarctica over roughly the same time frame.  Antarctic sea ice cover has seen record extents over this period but is a movable feast and since it is in general only around one meter thick it can see massive swings if warm air masses arrive from the north.
Yet a recent study employing satellite radar finds Antarctic glaciers melting at an increasing rate.

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Say then that the current global net rate of continental ice loss to the oceans is 100 Gt/yr.  Given that the global oceanic mass is ~ 1.35e18 tonnes we have an annual increase in ocean mass of 0.0000074%/yr.  You are going to be waiting at the high tide mark a very long time indeed to get so much as your feet wet - assuming no other confounding factors.  To cross check that, the figures readily available on the internet give the volume of ice on Antarctica - representing around 90% of the volume of ice on the planet - as approximately 30 million cubic kilometres, weighing in at a hefty ~ 3e16 tonnes.  It is estimated that if this volume of ice were to melt, the resulting sea level rise would be 58 m or so.  The current annual melt of 100e9 tonnes then would result in a sea level rise of just under 0.2 mm/yr or 2 cm/century.  Not exactly cause for alarm and bailing on that beach front property deal.

*  Note that NASA are using imperial tons and I haven't done the conversions since it makes little practical difference - 1 imperial ton = 1.01605 metric tonnes.
I'll repeat my suggestion that most practical steps to reduce CO2 emissions are worth doing anyway (see Denmark). What's not to like?

21
Right.  The oceans are obviously not rising in average temperature in step with the air, there should be a large lag due to the huge heat capacity of that much water.

Has anyone checked the math for the suggested volume increase of the total ocean water content caused by that temperature increase, then related that to the ocean surface area x the rise in ocean level?

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Sea level rise is very slow
Citation, please!

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New York is expected to see the sea level rise by about three feet by the end of the century. That is if global temps rise by five degree.
Citation, please!

See here!


Simply demanding citations leaves me no clue to what your beef is. But whatever...

http://e360.yale.edu/features/rising_waters_how_fast_and_how_far_will_sea_levels_rise

" Things today are more certain. In its latest report, released on September 27, the IPCC finally could and did put a number on ice flow from the poles. The result was an estimate of sea level rise of 28 to 98 centimeters (a maximum of more than three feet) by 2100 -- more than 50 percent higher than the 2007 projections. "We have our arms around the problem well enough to say there's a limit to how crazy things are going to get," says Ted Scambos, head scientist at the U.S. National Snow and Ice Data Center. "

Again I have no idea what your beef is but this number is all over the internet for anyone to find. There was even a sciam article recently.

I call this a very slow rise and it is in the context of the current discussion. But by historical standards it is very fast.

You (ppnl) made two claims:
  • Sea level rise is very slow
  • New York is expected to see the sea level rise by about three feet by the end of the century. That is if global temps rise by five degree..

I just wondered what figures you were working with. There is the most recent NOAA (PDF) report which suggests a range of projected sea level rise between at the very least 30 cm and an upper "extreme" of 2.5 metres by 2100. There is a trend that measurement has outstripped prediction with previous estimates consistently being revised upwards. And it won't stop rising at the end of the century, either. I'm OK. I live around 300 metres above current sea level. Those living at or near the coast in the US might not be so lucky.



23
Because socialism is bad.

So all the Western nations that have it are socialist systems.
Thanks for showing your intelligence.

Regards
DL

I can't think of a counter-example, offhand; Can you?


Many.

Regards
DL
List them then!
24
Right.  The oceans are obviously not rising in average temperature in step with the air, there should be a large lag due to the huge heat capacity of that much water.

Has anyone checked the math for the suggested volume increase of the total ocean water content caused by that temperature increase, then related that to the ocean surface area x the rise in ocean level?

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Sea level rise is very slow
Citation, please!

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New York is expected to see the sea level rise by about three feet by the end of the century. That is if global temps rise by five degree..
Citation, please!

See here!
25
Because socialism is bad.

So all the Western nations that have it are socialist systems.
Thanks for showing your intelligence.

Regards
DL

I can't think of a counter-example, offhand; Can you?