Launch countdown

[cncdoc]

I'm gratified TT#4 went well.

 

I'll be in the neighborhood all week. I'm setting up a machine east of I95 on Southern.

 

I will drop in on you from time to time. Let me know if you need me to bring anything.

 

BTW My wife bought a 2004 Nissan Altima (new) the 2.5 liter (or litre to you) developes 175 bhp @ 4000 rpm. The 3.5 gives a whole 250 bhp @ 5K and it's normally aspirated. It's about 100 lbs difference. Just some interesting information on recips and what their doing as opposed to what 7 liter a/c engine does, and what your rotary should do.

 

[John Slade]

For those who've been following my progress toward actually flying this bird, the plane is now officially certifiable. So am I, but that's another story.

 

Take a look at:

 

http://kgarden.com/cozy/chap27.htm#murphyslaw

[CBarber]

My pulse quickened with anticipation......so, April Fools it is????

 

No pressure, but you have a contingent of rotary pusher folks relying on you being a success. But, no pressure, really

 

All the best,

 

Chris

[dust]

Hi, john, talked with largeprime today and he said you is havin a heating problem, coupla of stupid thoughts

 

how is the air you have the ferrari fan bringing into the enfine area leaving the engine area, your cowling really appears wonderfully tight

 

have you considerred using the exhaust pipe insullator as an augmentor to help push air out from under cowling

 

have you wrapped the exhaust to turbo with insulation or enough insulation

 

Thanks for showing mike such a great time and he took great pics of your bird, saw your instrument panel with four ugly knees below it, the back of you and the bottom of your shoes while you attached canard bolts, fortunatly i am not arabic and find no insult by seeing the bottom of your shoes.

 

enjoy the fiddling

 

dust

[mplafleur]

I was thinking that the cowl flap was still closed while we were going down the taxiway, but I don't think it would make a difference as the top cowling was off. I don't remember if you said it was used to draw air out or help push it through.

 

As the rad is well below the engine, maybe there isn't enough pull from the water pump to get it back up to the engine. Just thinkin' out loud.

[John Slade]

Thanks for the thoughts. I've been "out of the loop" for 2 days flying and doing approaches in a Cozy IV in preparation for flying my own.

 

The issues with my own bird continue, but cooling isn't really identified as a problem [yet]. Discussions on the fly-rotary list have established that I'm doing just fine with cooling. Given that its a pusher with minimal airflow I'm seeing about what one would expect.

[John Slade]

I've just finished a write-up of my post inspection progress and Cozy flight experience at http://kgarden.com/cozy/chap28.htm

 

I'll add pictures later.

 

Enjoy....

[noodles]

Disclaimer--Some of you may already know your heat trasfer -- I attempted to make this user friendly. It should be fairly accurate, but at the same time if someone has a PHD in thermodynamics or heat transfer cut me some slack.

 

 

 

A little advice about the turbo and your glass.

 

Heat moves in 3 ways.

 

Light----Sunburns

 

Fluid----Boiled water and forced heating (water and air are both considered liquids)

 

Solid----Hot concrete

 

 

Light---When you put your shield on your turbo, paint the visible side flat white. This will help limit the “radiation” of heat from the heat shield to the cowl. Basically the heat via light is emitted from your turbo. It travels from the turbo to the next barrier “heat shield”. Depending on the color of the barrier the heat will either bounce back, or it will be retransmitted. This is why your heat shield is probably aluminum; it’s good at bouncing the heat back. If you can polish the turbo side of the shield it will bounce heat a little better.

 

If room allows you may want to apply an moderate angle so it doesn't bounce directly back to your turbo.

 

The only bad side is that heat doesn’t just disappear it has to go somewhere. Shite in = Shite out

 

To help further limit the light heat that is hitting the inside of your cowling try using aluminum tape. Apply this securely to the area that is melting. Leave it shiny.

 

 

This why you’ll need to work on the second type of heat transfer “fluid”

 

Fluid--You are already working on this one, air is a fluid the quicker you move it across the turbo the better off you are. If you can increase the flow across the turbo in anyway this would dramatically decrease the amount of stagnant heat in the air collecting between the turbo and the Cowling interior.

 

Air has the ability or capacity to remove or take the heat from your turbo. This is heat capacity, the more air you can move across the turbo the better off your cowling is.

 

As you move air across a heated surface i.e. turbo it begins to remove the heat that was stored in the turbo.

 

Now depending on fresh the air and how hot the day the air’s heat capacity may already be half way to it’s max capacity. As the air moves across the turbo it will remove the heat until it’s saturated . There are graphs to help further explain this. It is not a linear process.

 

 

As mentioned before shite in = shite out. The heat is now in the air i.e. fluid. Assuming you have maximized the heat capacity of the air you will now want to get rid of it.

 

Solid—This one is easy if your cowl is making contact with the turbo is melts, common sense but decided to add it anyhow.

[Aaron]

If you need to talk about this heat prob though, its good to use the right terms:

 

Light->Radiant

Fluid->Convective

Solid->Conductive

 

I know you know these terms but it is good for everyone to know them.

 

A nice looking silica fabric/composite heat shield:

http://www.hannestrnka.com/heat_shield.htm

 

Note he's left it the natural flat black. Painting it white would reduce the amount of heat radiated to the cowling, but heres the other thing about heat transfer

 

conductive effects & convective effects >> radiative effects

 

So, work on getting the shields air-gapped, work on getting them sealed, and then worry about paint and reflective surfaces would be my opinion on the matter.

 

No PhD on heat trans here, just a lowly BS. But I've got a great library of heavy books on the subject

[dust]

Another good friend i have that is an automotive engineer told me that the BIGGEST problem chrysler had was "radiative effects"

 

We do have allot of automotive engineers in metro detroit

 

Line of sight transfer can end up in places you just don't think will get hot

 

enjoy the build

 

dust

[Aaron]

I'd agree in a chrysler, where the turbo is essentially unshielded and airflow under the hood is slower than in the plane. Radiative effects vary with the 3rd or 4th power of the temp difference.

 

In other words the heat radiated from a turbo at 1500 F is 30 times greater than the heat moved from a heat shield at 400F.

 

I'd have to ask your engineer, but I think in general automotive heat transfer is designed around stop and go driving conditions, where the flowrates of air under hood are minimal. This would also make radiative effects more important.

 

But your post does bring up an important point- the only way to know is to do.

[noodles]

Yes,

 

You are right, about the terminology. I just didn't want to stump a newbie. But now that you've added to the conversation it will be that extra bit of information.

 

I'm still in Newfoundland and have no heavy books with me, it was all frontal lobe.

 

The site looks good, I have some books at the house about using Carbon fiber for your intake system as well.

 

There are several documentated attempts. I'm surprissed more folks aren't using it.

 

 

 

 

Nathan,

[dust]

It's top on my list, the problem will be making a "perfectly smooth" removable form to lay it up over.

 

enjoy the build

 

dust

[John Slade]

For those who might be interested, there's a write-up of my first flight at http://kgarden.com/cozy/chap28.htm#firstflight