Am 05.02.2016 um 06:49 schrieb Sven Littkowski:

> Now let me answer your question. The cylinder rotates, and its inner
> sides contain objects, such as buildings, moving objects (like humans
> and vehicles, maybe even animals), and also trees and other plants.
> Those all will "push" the air and get thus the air into motion. Over
> time, the air at around all these objects will gain almost the same
> speed as the inner walls of the cylinder and the objects on it.
> 
> But since air is flexible, the air at the outer areas moves initially
> faster than the air along the central middle axis of the cylinder, but
> over time, that air there tends to gain speed, too, pushed by the air
> from the outer areas.
> 
> However, since air has its own inertia, the air especially at the inside
> will never reach a full 100% of the air movement close to the walls of
> the cylinder.

You may be pretty much mistaken there.

First, let's look at what would happen /without/ any external influence.
If we do not input any energy, the system will approach equilibrium,
which would be characterized by the following conditions:

- All portions of the system will have the same temperature. As a
consequence, there will be no temperature-induced air movement.

- There will be no friction between the air and the ground, as any such
friction would transfer energy between the two, and therefore constitute
an indication that equilibrium has not yet been met. Note that absence
of friction between air and ground can only be achieved by having the
air rotate at the same speed as any ground structures at the same heigth.

- There will be no turbulences within the air, as any such turbulences
would transfer energy around within the body of air, and therefore again
constitute an indication that equilibrium has not yet been met. Note
that the absence of turbulences can only be achieved if the air moves
like a solid body would.

=> Without external energy input, the angular velocity will become
uniform across the entire system.


Now let's see what happens if we add a sustained heat source:

- If we heat up the air near the central axis, nothing much will happen:
Warmer air tends to travel inward, so we don't get any convection. We
would get some slow heat transfer outward, and a change in the pressure
gradient, but no noticeable movement.

- If on the other hand we heat up the air near the ground, that warmer
air will indeed, through convection, exchange its place with the cooler
air near the axis. However, as both layers of air initially have the
same angular velocity but different distance to the center, they have
different angular momentum, which needs to be conserved. The only two
mechanisms by which this can be achieved is (a) by transfer of angular
momentum from the warm air moving inward to the cold air moving outward
by means of friction (which is inefficient), or (b) by a change of
angular velocity in the respective bodies of air.

As a consequence, the warm inward-moving air will increase its angular
velocity beyond that of the ground, while the cold outward-moving air
will decrease its angular velocity below that of the ground, initially
resulting in a net wind at ground level.

- If the heat input continues, the convection will also continue, and
turbulences in the air will not subside; however, the net wind at ground
level will lead to a transfer of rotational energy between ground and
air until both ground and ground-level air generally move at the same
speed. Note that this effectively speeds up the ground-level air (while
slowing down the ground).

- The mechanism by which higher-level air is sped up, however, does
/not/ subside; to the contrary: With the ground-level air speeding up,
the difference in speed gets even more pronounced.


=> From what I see, we should expect the air near the ground to be
motionless overall, with winds only blowing from cooler ground regions
to warmer ones, while closer to the center we should expect a /higher/
angular air velocity than near the ground.

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Hi again, and thanks for the interesting sup topic we have entered here! :-)

At this interesting point, I would like to get some more input. I am
even considering, to post this question inside some Facebook or
independent Internet forum.

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On 2/5/2016 11:34 AM, Sven Littkowski wrote:
> Hi again, and thanks for the interesting sup topic we have entered here! :-)
>
> At this interesting point, I would like to get some more input. I am
> even considering, to post this question inside some Facebook or
> independent Internet forum.
>

Do so. :)
It has been asked before for instance

https://www.google.co.uk/#q=o%27neill+space+cylinder+air+pressure+gradient


-- 

Regards
     Stephen

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Thanks for the link. Reading through some of the Google search results
of that URL, I feel my thoughts confirmed (though they use a better
English than I can use, due to many correct terms, like "jet stream",
"coriolis", "topography", and such.

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On 02/05/2016 12:02 AM, Thomas de Groot wrote:
> On 5-2-2016 6:24, Sven Littkowski wrote:
>> Hey, where is my long posting about air movement inside the cylinder?
>> What happened with it? I worked over half an hour on that detailed answer.
>>
>
> So is my mention of reading 'Rendezvous with Rama' (where, by the way, the topic is
also treated).
>
???  They both came through fine for me, using Thunderbird.

      -=- Larry -=-

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On 2/6/2016 7:22 AM, Sven Littkowski wrote:
> Thanks for the link. Reading through some of the Google search results
> of that URL, I feel my thoughts confirmed (though they use a better
> English than I can use, due to many correct terms, like "jet stream",
> "coriolis", "topography", and such.
>

That was only one link that I could retrieve from memory. If you vary 
the terms there should be more relevant results.


-- 

Regards
     Stephen

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On 6-2-2016 8:36, Larry Hudson wrote:
> On 02/05/2016 12:02 AM, Thomas de Groot wrote:
>> On 5-2-2016 6:24, Sven Littkowski wrote:
>>> Hey, where is my long posting about air movement inside the cylinder?
>>> What happened with it? I worked over half an hour on that detailed
>>> answer.
>>>
>>
>> So is my mention of reading 'Rendezvous with Rama' (where, by the way,
>> the topic is also treated).
>>
> ???  They both came through fine for me, using Thunderbird.
>
>       -=- Larry -=-
>
Strange... Here (Thunderbird) both messages have disappeared. Also on 
the site.

-- 
Thomas

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Am 06.02.2016 um 08:53 schrieb Thomas de Groot:
> On 6-2-2016 8:36, Larry Hudson wrote:
>> On 02/05/2016 12:02 AM, Thomas de Groot wrote:
>>> On 5-2-2016 6:24, Sven Littkowski wrote:
>>>> Hey, where is my long posting about air movement inside the cylinder?
>>>> What happened with it? I worked over half an hour on that detailed
>>>> answer.
>>>>
>>>
>>> So is my mention of reading 'Rendezvous with Rama' (where, by the way,
>>> the topic is also treated).
>>>
>> ???  They both came through fine for me, using Thunderbird.
>>
>>       -=- Larry -=-
>>
> Strange... Here (Thunderbird) both messages have disappeared. Also on
> the site.

Same here: I /know/ they were there, but I can't seem to find them anymore.

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On 2/6/2016 1:42 PM, clipka wrote:
> Am 06.02.2016 um 08:53 schrieb Thomas de Groot:
>> On 6-2-2016 8:36, Larry Hudson wrote:
>>> On 02/05/2016 12:02 AM, Thomas de Groot wrote:
>>>> On 5-2-2016 6:24, Sven Littkowski wrote:
>>>>> Hey, where is my long posting about air movement inside the cylinder?
>>>>> What happened with it? I worked over half an hour on that detailed
>>>>> answer.
>>>>>
>>>>
>>>> So is my mention of reading 'Rendezvous with Rama' (where, by the way,
>>>> the topic is also treated).
>>>>
>>> ???  They both came through fine for me, using Thunderbird.
>>>
>>>        -=- Larry -=-
>>>
>> Strange... Here (Thunderbird) both messages have disappeared. Also on
>> the site.
>
> Same here: I /know/ they were there, but I can't seem to find them anymore.
>

Yes, me too.


-- 

Regards
     Stephen

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Looks like a web page scripting problem (PHP?), or like a database
problem. In both cases, it needs to be investigated as it is a serious
problem.

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