This past Summer, took our 15 foot fiberglass on a long road trip
instead in the usual half mile to the marina. The tires are the small
4.80-8 utiltiy type tires, and needless to say, they overheated
badly.....
long story, but I'll be upgrading to a biger tire this Summer.

Here's my question. It seemed that the speed at which the load was
being carried created the heat. While pondering the trip home
(semi desperate and after a few beers) I considered filling the tires
with water (say 50%) in an attempt to dissipate the heat to the rims.

I never did this, but have pondered the the effects of water in a tire
at speed. Would the balance go for a bundle or would the water be
thrown evenly within the tire by the certifugal force?

I made the trip home by upping the pressure to 60 p.s.i. and by
driving slower.

Would water have helped of would I have been courting a disaster?


nitrogen helps tires run cooler

"Wwj2110" wrote in message

nitrogen helps tires run cooler

How does that work?

JG

They have it at race tracks. Otherwise you need a tank of it. Know anyone
in the hvac business, they use it to purge refrigerant lines while they
braze. Not really likely to help enouhg to be worth the trouble though.
The other posters are right, bigger wheels are the right solution.

"John Gaquin" wrote in message
...

"Wwj2110" wrote in message

nitrogen helps tires run cooler

How does that work?

JG

Hydrogen is even better yet (better heat transfer coefficient). It is what is
used to cool the 1000 megawatt generators at power plants as air can't carry the
heat from resistance in the windings away fast enough. Just watch out for
flames or sparks. Also hydrogen tends to diffuse through the tire so you have
to replenish it more often.

JJ

On Sun, 26 Oct 2003 00:00:08 GMT, "Lawrence James"
wrote:

They have it at race tracks. Otherwise you need a tank of it. Know anyone
in the hvac business, they use it to purge refrigerant lines while they
braze. Not really likely to help enouhg to be worth the trouble though.
The other posters are right, bigger wheels are the right solution.

"John Gaquin" wrote in message
...

"Wwj2110" wrote in message

nitrogen helps tires run cooler

How does that work?

JG




James Johnson
remove the "dot" from after sail in email address to reply

On Sun, 02 Nov 2003 00:31:47 +0000, James Johnson wrote:

Hydrogen is even better yet (better heat transfer coefficient). It is what is
used to cool the 1000 megawatt generators at power plants as air can't carry the
heat from resistance in the windings away fast enough. Just watch out for
flames or sparks. Also hydrogen tends to diffuse through the tire so you have
to replenish it more often.


Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Lloyd Sumpter

Lloyd Sumpter wrote:

Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Hydrogen cooling is pretty common. He isn't, however, thinking about
just where that heat in a tire is supposed to go.

It's not like there is a heat exchanger to remove the heat from the gas
that was heated by the rubber surrounding that gas to begin with.

Rick

On Sun, 02 Nov 2003 19:48:12 GMT, Rick wrote:

Lloyd Sumpter wrote:

Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Hydrogen cooling is pretty common. He isn't, however, thinking about
just where that heat in a tire is supposed to go.

It's not like there is a heat exchanger to remove the heat from the gas
that was heated by the rubber surrounding that gas to begin with.

The wheel. I can see how the heat conductive properties of the gas can
make a difference conducting heat from the tire to the wheel at
different rates. Especially since the rubber itself isn't a good heat
conductor.

Steve

On Sun, 02 Nov 2003 11:05:12 -0800, "Lloyd Sumpter" wrote:

On Sun, 02 Nov 2003 00:31:47 +0000, James Johnson wrote:

Hydrogen is even better yet (better heat transfer coefficient). It is what is
used to cool the 1000 megawatt generators at power plants as air can't carry the
heat from resistance in the windings away fast enough. Just watch out for
flames or sparks. Also hydrogen tends to diffuse through the tire so you have
to replenish it more often.



I've worked at Perry, OH; Enrico Fermi, MI; Calvert Cliffs, MD; Oyster Creek,
NJ; Salem, NJ; Peach Bottom, PA as a contractor for maintenance outages and as
part of the operating staff for 2 of them. They ranged from 600 MW to 1300 MW.

In all of these the internal cooling for the generator was recirculating gaseous
hydrogen. The H2 is recirced through the windings picking up heat and then pass
through water cooled heat exchangers to give up the heat. The systems are
built into the generator casings so unless you were part of the disassembly you
would not know of the specifics.

To use air the generators would have to be much larger to provide sufficient
surface area to remove the heat generated by resistance in the windings (i.e. it
is cheaper to build it this way). They have elaborate bearing seals, and no
oxygen inside (nitrogen purged for maintenance or prior to filling for
operation) to prevent combustion. So doggie-donuts yourself.

JJ

Having worked in a 1000 MW generating station, I can safely say this is
doggie-donuts. I wouldn't have hydrogen (or any explosive gas) within
100ft of a high-power generator!

Lloyd Sumpter

James Johnson
remove the "dot" from after sail in email address to reply

I don't think they run cooler, but I know that using nitrogen the pressure
stays more consistant as the tire heat up
"John Gaquin" wrote in message
...

"Wwj2110" wrote in message

nitrogen helps tires run cooler

How does that work?

JG

Kevin Anderson wrote:
I don't think they run cooler, but I know that using nitrogen the pressure
stays more consistant as the tire heat up

Do you guys stay up late making this stuff up or do you really, honestly
believe that?

Have you ever heard of - much less read - the "gas laws'? Look up a
French chap named Charles and Gay-Lussac and their particular
contribution to the art.

Exactly how do you "know that using nitrogen the pressure stays more
consistant (sic) as the tire heats up"?

The reason nitrogen is used in high performance tires (usually aircraft)
is that it will not support combustion or oxidation of rubber compounds
in a very high temperature application. Compressed nitrogen is normally
dry, very low in moisture content as well as completely free of oil
which is a contaminant delivered by many air compressors. All the normal
gas laws still apply.

The only thing worse than the general lack of basic scientific knowledge
shown here is the willingness of people to post that they "know" that
the laws of physics simply don't apply.


Rick