Cozy, Long ezy, and diesel engine.

Morgans wrote:

Also, keep in mind that you only
need to de-ice the leading edge of the wing (look at how much boots
cover).


Different princples at work. If you *melted* the first few inches of ice,
it would run back and re-freeze, before it got off the wing. Bad thing.
VERY bad thing, as in guaranteed crash, after about 1/4" of ice.

I couldn't find any definitive references with a quick search, but I'm
pretty sure that jets with heated wings, only heat the leading edge, not
the entire wing surface.

I suspect that the ice melts slowly enough that it evaporates (or
sublimates) long before it can run back over the wing.


So the area is probably closer to 2' times the wingspan which
means 50-80 sq. ft. one a typical light airplane.


Nope, see above. Good for crashing, if it did stay hot enough to melt ice.

And you don't need to coolant at 180F+ to deice a wing, so you can push
the coolant through a lot more area than a radiator and still keep
sufficient temperature to melt or prevent ice.


You will have to add another pump (more weight) to move that "cooler" water,
then. ALL of the water that comes out of the engine is at 180 degrees.


Preventing it is easier than melting an accumulation to be sure. This
holds with other systems such as TKS as well.


Different, once again. Preventing it from forming on the leading edges, and
letting it freeze further back does no good. TKS keeps everything that runs
back from freezing, because the antifreez has mixed with all of the water
running back, to make a mixture that is above freezing.

If you melt it at the front of the wing with heat, the water must stay hot
enough to run ALL OF THE WAY back, and off of the wing. Jet engines have
enough waste heat to do that. IC engines DO NOT. Get that through your
head! It is not done, because it CAN NOT be done! Get it?

Sorry, I've not seen any data that supports this conclusion. I don't
think Jet engines are that much less efficient than piston engines,
especially given that amount of heat they directly eject out the tailpipe.


For my final argument, why are wing radiators not commonplace?


I'd guess cost and complexity would be two big reasons.


Yes, but you missed the biggest one. Weight. Weight. Weight. If it were
cost and complexity, someone would still do it. They *will not* sacrifice
the weight.

Yes, I'm sure weight is another reason, although this could be minimized
if the coolant channels were formed integrally with the leading edge
skins. However, that would then bring back the cost issue.


Matt

"Matt Whiting" wrote

Sorry, I've not seen any data that supports this conclusion. I don't
think Jet engines are that much less efficient than piston engines,
especially given that amount of heat they directly eject out the tailpipe.

Pure volumes of fuel burned, is the all important factor. What does a
modern airliner burn per hour. Doug, or other jet qualified dude? 50
galons per hour for a regional turbo prop? 100 or more for a smaller
turbofan? Compared to 20 or 25 for a piston. Not even in the ballpark.
Not enough energy avaliable.

That many gallons being burned is a lot of energy available, and a
percentage can be used for anti ice. It is no free lunch, and the jets burn
more fuel when the anti ice is on. I don't know how much, but it is a large
enough factor to have to be calculated, AFAIK. Bleed air is used, and that
is capable of a tremendous volume, at a high temperature. An airplane
piston engine might be able to make that much heat and volume from
comperssed air, if it ran a rotary comperssor, and didn't have to mess with
a propellor. It would not fly very good without a prop! g

You also mentioned the water running back, only being heated from the front
with jets. OK, but they can heat it hot enough to evaporate some of it,
and get the rest hot enough that it does not refreeze before running off.
The piston engines could not put enough heat out, like the turofans. Even
the turboprops have to use boots.

Yes, I'm sure weight is another reason, although this could be minimized
if the coolant channels were formed integrally with the leading edge
skins. However, that would then bring back the cost issue.


Matt

If it would work, someone would have done it, with the cost not being an
object. The weight issue is too much to overcome, along with the
complexity. Still, the whole thing comes back around to the fact that it
demands more energy than is available.

Give it up. I know you won't; you just want to tilt at windmills. That's
OK, if that is your thing. It is not mine.

I'm done here. Good luck.
--
Jim in NC

"Ernest Christley" wrote

If you're really interested, the FlyRotary mailing list archives will
reveal that quite a few planes are flying with this setup now.
Unfortunately, I'm not one of them yet. Most had overheating problems
initially, and had to make a modification or two to get things under
control, but there are now quite a few examples of how to get 170Hp out
of a rotary without overheating using a couple GM condenser cores. It
the last few to report first flights have not had heating problems.

Wow, I never would have guessed that they have that much area. I'm actually
a little bit skeptical. g

I'm curious. Other than availability, why has that GM condenser become so
popular? Any clues?
--
Jim in NC

In article , Morgans wrote:

"Ernest Christley" wrote

If you're really interested, the FlyRotary mailing list archives will
reveal that quite a few planes are flying with this setup now.
Unfortunately, I'm not one of them yet. Most had overheating problems
initially, and had to make a modification or two to get things under
control, but there are now quite a few examples of how to get 170Hp out
of a rotary without overheating using a couple GM condenser cores. It
the last few to report first flights have not had heating problems.

Wow, I never would have guessed that they have that much area. I'm actually
a little bit skeptical. g

Look *closely* at a radiator. Notice how many of the 'vanes' there are in a
linear inch. Now, consider how _deep_ the section is.

Making up numbers out of thin air, if there are 6 vanes/inch, and depth of
the assembly is 3 inches, you've got 18 inches of radiating surface for
each square inch of 'frontal' area. For a 2'x3' frontal area, this comes
out to 108 sq ft of radiating surface.

2'x 3' = 6 sq. ft frontal, * 18x for 'radiating' surface area

If it would work, someone would have done it, with the cost not being an
object. The weight issue is too much to overcome, along with the
complexity. Still, the whole thing comes back around to the fact that it
demands more energy than is available.

Give it up. I know you won't; you just want to tilt at windmills. That's
OK, if that is your thing. It is not mine.



This is nonsense of the highest degree.

Everything that has ever been done has been done a first time.

In the piston world, no one is going to throw a lot of money at this unless
they think they can do it cheaply. Otherwise, they are wasting their money.
So to say that someone would have done it regradless of cost seems wrong to
me. The market potential is pretty small, so unless something is obvious,
it won't get done for profit. It will get done by someone who wants to know
how, why, or what if.

If you know how a jet can do it, then all you have to do is find out how
much you have to lighten the system, and how much energy you need to add to
the system.

You are helping by pointing out the problems that need solving, but not by
saying they are unsolvable.

This has been very interesting to me, a novice. But, my original intent was
to create enough heat to keep the fuel from jelling, not to de-ice the
wings. With that goal in mind, the wings could actually be insulated to help
hold the heat. There would be very little added cost, or weight. A fuel
pump (which is already on the aircraft) could simply pump more fuel that is
needed to the engine. Some of the fuel would be burnt, while some of the
fuel would run through a heat exchanger from the radiator, or engine oil,
then simply return to the tanks.

"LCT Paintball" wrote in message
news:qopTd.22302$zH6.12927@attbi_s53...
This has been very interesting to me, a novice. But, my original intent
was
to create enough heat to keep the fuel from jelling, not to de-ice the
wings. With that goal in mind, the wings could actually be insulated to
help
hold the heat. There would be very little added cost, or weight. A fuel
pump (which is already on the aircraft) could simply pump more fuel that
is
needed to the engine. Some of the fuel would be burnt, while some of the
fuel would run through a heat exchanger from the radiator, or engine oil,
then simply return to the tanks.

Sorry you got lost in the rush of absurdity. Your problems are solveable.

Yes, the fact that the tanks you are using will be fiberglass over foam,
instead of aluminum, would give you a pretty good chance of your idea
working. Keep in mind that you will not always be able to get auto diesel.
Be sure that your engine will be able to burn jet A.

There was some talk about auto engines, and jet A. Seems the injection
pumps on most auto engines can not stand up to jet A. The auto diesel has
good lubrication qualities, while jet A has no lubricating qualities. The
seals wear completely out, and the pump stops injecting. The diesel engines
now flying, like the Thielert, (or however it is spelled) have seals that do
not depend on lubrication from the fuel, so no problem. I recall that it
can burn auto fuel, also, but I'm not sure on that one. Perhaps someone out
there knows that answer.

If I were going to do what you are thinking about, I would put a thermometer
in the tank(s), and also include a heat exchanger bypass, so when you are
burning jet fuel, you can stop heating the fuel.
--
Jim in NC

.. I recall that it
can burn auto fuel, also, but I'm not sure on that one. Perhaps someone
out
there knows that answer.


The Thielert can run auto diesel in europe, but the american mixtures are
not recommended due to high sulfur and other contaminants. This will likely
change in 2006.

Sorry you got lost in the rush of absurdity. Your problems are solveable.


I'm not sorry. I haven't been around long enough to even ask good questions,
so this kind of discussion really gets me thinking. I love to invent new
things. I have the skills and tools to do so, but I don't have the expertise
in the aircraft industry, yet.

Morgans wrote:
"Ernest Christley" wrote


If you're really interested, the FlyRotary mailing list archives will
reveal that quite a few planes are flying with this setup now.
Unfortunately, I'm not one of them yet. Most had overheating problems
initially, and had to make a modification or two to get things under
control, but there are now quite a few examples of how to get 170Hp out
of a rotary without overheating using a couple GM condenser cores. It
the last few to report first flights have not had heating problems.


Wow, I never would have guessed that they have that much area. I'm actually
a little bit skeptical. g

I'm curious. Other than availability, why has that GM condenser become so
popular? Any clues?

Tracy Crook used a couple from a junkyard, 'cause he got them for $5
each. He was going to just use them for sizing purposes, but they had
the unfortunate quality of working very well, so he just kept them.

Most builders have just sort of followed a proven design. It's cheap.
It fits. It's lightweight. It works. I don't know if there is a better
deal in aviation.