Friday 2010-12-10 Dev. video update and Discussion

[Oleg Maddox]

Originally Posted by Wutz

Here is a Merlin engine being started, but one see no flames at all, maybe only visable during night time?

Here is more sound of prop then of engine really, especially with High RPM.
But thanks for the sample

[Oleg Maddox]

Originally Posted by Rodolphe

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More reading about exhaust flame vs detonation ~ grade of fuel used.










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Yes, we have it. but also with the drawn samples

[Oleg Maddox]

Originally Posted by Richie

Oleg.....Spitfire flames in the dark and they are blue!!

Sure, with high RPM and right mixture.

[Sutts]

Oleg,

In terms of the initial startup flames I think you have the perfect colour already, no more red required.

I attach comparison shots from the previously posted P-51 Old Crow startup against the flames in your video. You have them spot on I think.

Once the engine is running it looks like red/blue is the expected colour though. I haven't seen any yellow flames from a running engine yet and the colour chart previously posted only mentions yellow flames when the spark plugs are defective.

Would be nice to occasionally see the large lazy flames caused by an overpriming stack fire too.

Thanks

[fireflyerz]

Lets not get too carried away... PLEASE -Watch the whole vid to see what happens as engine revs are increased and decreased.

http://www.youtube.com/watch?v=Xs_qt4GCj4A

[T}{OR]

Originally Posted by fireflyerz

Lets not get too carried away... PLEASE -Watch the whole vid to see what happens as engine revs are increased and decreased.

Very nice find!

And a good point. It is important to note the engine RPM changes. When they occur, it affects how the fuel is burning in the engine. Variable and constant RPM's are two completely different processes happening inside the cylinder. In other words - when on constant RPM (provided we have the ideal mixture) the engine is burning fuel just like it should have, while with variable (changing) RPM the mixture and overall fuel burning process is far from ideal.

i. e. - for the very same reason there are two different fuel consumption figures in cars: one for driving in a city where throttle changes are frequent and fuel consumption is higher, and another for highway driving where fuel consumption is much lower.

[Stefem]

Yea, a bit or red and blue would make it more realistic

[SlipBall]

Originally Posted by FG28_Kodiak

Have found this table for the Allison V-1710 Models 'E' and 'F' (from Allison Service School Handbook ALD-SSH-5) I know its not a Merlin

Excellent find FG28_Kodiak

[Tbag]

Oleg&Team, thanks for the update. Completely OT but a very interesting document for the future:

http://www.cockpitinstrumente.de/arc...0Air%20War.pdf

[Tbag]

and another one:

http://www.cockpitinstrumente.de/arc...%20WW%20II.pdf