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

[Sutts]

Originally Posted by Blackdog_kt

Exactly. In general, hot=blue, cool=red/yellow, plus a flame that's seen directly exiting the piston will be hotter than a flame seen after travelling the entire length of the exhaust pipe.

So, since the colour is a function of exhaust gas temperature, i guess that running on higher power will produce bluer flames. Also, leaning the mixture at night could be done by watching the flames, you just have to lean until the highest exhaust gas temp which means the bluest flame you can get, then enrich it again just a tad from that point.

I might know how the stuff generally works but it don't know what the correct colour for each circumstance is. However, i'm really excited about these features because they give the impression of a real, working machine under the hood. Excellent update!






...and the way pilots of prop driven aircraft adjust their mixture today is by, guess what, a temperature gauge that monitors how hot the exhaust gas is. So you're correct generally, except the part where you say it has nothing to do with temperature. This is also not opinion but physics, whatever burns hotter is to the blue/white side of the spectrum and stuff that burns cooler is to the red/yellow side. It's the reason even the stars are not all the same colour. Cheers


Edit: I just saw you corrected it yourself

Unfortunately, the stills I've captured from the Just Jane Lancaster nighttime runup show exactly the opposite Blackdog......when RPM is high we see short red flames. When idling the long blue flames are ejected intermittently. Could be that this old Lanc just isn't tuned up properly like a flyer would be.

Dunno!

EDIT: Sorry, it was someone else who related colour to engine speed. I agree it is temperature based like you say and the temperature at any RPM will be dependent on the efficiency of the burn...mixture, cold/warm engine, degree of wear in the barrels etc.