[snowsislander]

Boscoli points out a phenomenon discovered in the 1930s but -- like many such anomalies -- virtually ignored since. French physicist Georges Ranque discovered that if you make a body of gas rotate, as in a turbine, the hottest (most energetic) molecules are somehow separated to the outside of the mass, while the gas at the centre gets colder. It is relatively easily experimentally to make a 'Ranque tube' where the difference in temperature between air in the middle and air at the outside is more than 100 degrees C, simply by causing the air to rotate.

This isn't a subject that I know much about, but from doing some casual Google searches, surprisingly the above paragraph appears to be true. Here is what appears to be a current version of the device (a "Wirbelrohr"):

Apparently, all it takes is some compressed air, and out comes cool air on one side and hot air on the other.

One source mentioned that as far back as 1958 such a device appeared in the old Scientific American Amateur Scientist column.

Commercially, there appears to be a company that sells these devices. Here's an English translation courtesy of Google of a page from their website:

 

 

Principle of the wirbelrohrs

 

 

Our wirbelrohre are available in many sizes with different cooling performance.
Standing: 308BSP and 208BSP
Lying: 106BSP and 328BSP

Wirbelrohre

The principle of the wirbelrohrs:

The wirbelrohr was discovered 1930 by the French physicist Georges Ranque. Vortec was the first enterprise, which developed effective applications of cooling for the industry on the basis of the eddy tubing principle use in general practice. Here a short description of the eddy tubing principle follows.

Liquid, which turns around an axle - like a Tornado -, as "eddy" designated. A wirbelrohr produces an eddy from compressed air and separates it into two rivers, a hot and a cool air stream. Compressed air occurs a cylindrical generator, which is proportionally larger than (for a long time) is called pipe, where she shifts air there present in turn. Afterwards circling air at the inner wall of the hot pipe is pressed along, where it reaches speeds of 1,000,000 U/min. At the end of the hot pipe a small part of this air escapes by a needle valve at the hot-air withdrawal. Remaining air is led back obligatorily with lower speed by the center of the occurring air flow. The warmth in more slowly flowing air is transferred to faster flowing occurring air. Undercooled air flows by the center of the generator to the cool air withdrawal.

 

The wirbelrohre of ITW Vortec are available in a broad size scale for different process and applications of point cooling. They offer still higher cooling performance than the cool air pistols.

Characteristics:

• Cooling without refrigerants (CFC/HCFC) and without moved parts, thus reliably and interference-proof
• no electricity, intrinsically safe, no HF disturbances
• compact and easy building method, thus easy installation, also within with difficulty accessible, narrow ranges

Model	Compressed air 100 PSIG	Compressed air 6.9 bar		kcal/h	> > > Mailsupport > > > telephone support
	Consumption SCFM	Consumption l/min.	Temperature Waste °C *
106bsp-2-h	2	57	34	25
106bsp-4-h	4	113	44	64
106bsp-8-h	8	227	45	101
208bsp-11-h	11	312	47	161
208bsp-15-h	15	425	47	227
208bsp-25-h	25	708	37	378
308bsp-35-h	35	992	42	668
328bsp-50-h	50	1416	44	756
328bsp-75-h	75	2125	47	1134
328bsp-100-h	100	2833	43	1512
Achievement in kcal/h with compressed air dried by 21°C, on a dew point of -40°C. * The temperature of the air flow can be lowered additionally around 11°C. Lower air flow temperatures can be reached, as the hot-air stream is strengthened by the attitude of the needle valve. The needle valve is in the hot-air withdrawal. Wirbelrohre produce at smaller air flow, lower temperatures and smaller kcal/h achievement. Accessories:
Model	Description
106GEN	independent generator for wirbelrohr indicate 106 when ordering: 2, 4 or 8 SCFM
106MCBSP	Cold the muffler for wirbelrohr 106
208GEN	independent generator for wirbelrohr indicate 208 when ordering: 11, 15, 25 or 35 SCFM
208MCBSP	Cold the muffler for wirbelrohr 208 or 308
208MH	Being called muffler for wirbelrohr 106 or 208
308MH	Being called muffler for wirbelrohr 308
328M	Cold or being called muffler for wirbelrohr 328
328XB	independent generator for wirbelrohr indicate 328 when ordering: 50, 75 or 100 SCFM

[S0122017]

The hottest atoms are the fastest moving. So in a whirl,
gasatoms that are faster move quicker to the outside and leave the slower behind.

voila, cooling inside heating outside.

It may very well be true that the sun is cooler at the core, afterall this isnt at all like an open fire and lot of fusion science is only a few years old.

Dont forget that the pressure in the centre of the sun has got to be enormous, and gas under pressure has its boiling termperature barrier increased. so maybe the inside is solid and cool afterall.