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

[Sutts]

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.

Perfect find fireflyerz, thanks for posting. Must have had the mixture bang on in this run up, lots of blue and more blue. A brief flash of orange/yellow flame on initial start - just like in the 1st Oleg video.

A red flame from a single stack at one stage I noticed.

I was so glad when they turned the lights off. No illumination of the side panels at all really - maybe very slight at one point but just immediately around the stacks. Best video yet.

Cheers

[KG26_Alpha]

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.

Wrong engine.

Totally different fuel system.

Why bother posting this its totally irrelevant to a Spit MkI Merlin

[klem]

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 example showing the persistence of the blue flame at night and why nightfighters like Hurricanes had the exhaust stack guard over them.

That's a Griffon engine btw but I expect the Merlins were similar especially according to anecdotal evidence from the actual pilots.

[JVM]

Hello Oleg!

If there is a program managing each exhaust pipe individually, could it be possible to expand it in order to make the exhaust flames yellow + puffs of black smoke + irregular firing tending quickly toward blue + no smoke (or slight stream of translucid grey), as Wutz video shows?
Exhaust flames at high RPM were indeed blue (assuming the pilots were managing mixture, which was generally the case!)

JVM

Agree that most accounts I've read also mention intercepting at night by spotting blue flames.

[moilami]

Originally Posted by Wutz

Well this is not a british engine but maybe this gives you an idea how it should look like?

Wow, got a signature!

[baronWastelan]

Sorry Oleg, had a spare hour this afternoon and a new add-on for an old sim, and just couldn't resist...

http://www.youtube.com/watch?v=1tzHTH2Jzhg&hd=1

[greypeace]

Hi Oleg,
I dont know where to post this query
First post got lost in last week update
Thank for the tip ( from a kind chap )to repost early in the new update so it will be seen ...
Sorry if I am out of place ,

QUERY:
I am finishing a FFB firmware project and I would like to know if BOB 's FFB handling will be compatible with the Microsoft FFB stick on which my firmware is based.
I am only using the "Spring" feature , The most important one ...

Thank you
gb

[engarde]

Originally Posted by Wutz

Well this is not a british engine but maybe this gives you an idea how it should look like?

Haaaahahaha i believe thats coming straight out of the block with no exhaust stubs?

I recall i did that after transplanting a 2 litre Ford engine in my little Mk2 Escort.

Drove it around for a bit with no bonnet/hood and no engine pipe.

Sounded like a demon on a short chain, although when i got back i realized i'd burnt pretty much everything off that side of the engine bay.

Aah good times.

[Skoshi Tiger]

It's lucky we've got so many experts on this forum especially in the field of chemisty. I on the other hand have only the basic high school level.

If you look at the first minute of so of this video, you'll see the flame changing colour due to the mixture of the fuel and air being burnt. If there is exess fuel in the mixture it will be a highly visible yellow flame, if it's the mixed fuel/air at the correct ratio it will be blue but almost invisible.

http://www.youtube.com/watch?v=IpuVOYRb2pU

In Olegs video we a an engine that has just been started. From the video shown the engine is barely ticking over.

Now the merlin engine had what's called a high overlap cam shaft, which means that the inlet and outlet valves are open at the same time for a long time durring the otto cycle. (It allows fresh fuel air mix to enter the combustion chamber at the same time as the last of the exahust gasses leave the combustion chamber.) This makes the engine more efficient within the engines power band BUT at low revs the engine engine runs rough due to incomplete burning of the fuel air mix in the combustion chamber. It's what known as a 'Lumpy Cam' in automotive circles. It means at low revs there is a lot of unburnt fuel in the exhaust gasses.

Now I know some people here want Oleg to demonstrate a 'Blue Flame' in an update video. I for one, most emphatically, do not want to see this!

Cheers!