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

[W32Blaster]

well not as simple as that.

The ideal mixture is about 14:1, also called lambda=1.

But if you have certain parameters of use like
RPM
accelaration,
Airtemperature high, low
Airpressure high, low
Cold motor (less evaporating fuel in cylinder and thus richer mixture needed)

etc. etc. etc.

you get lots of changes in actual needed air to fuel ratio. Many FuelInjection Systems are a not specified to recognize all those factors, where some really complicated carburators do.

So it´s not that simple one could say:
Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions.

[SlipBall]

That's a very good question. I think because of the fuel injection of the German fighters the Allied aeroplanes will have more fun with the flames.


Damm, I think I flooded her!...

Now you know the real reason, why I fought so hard for realistic start up's:-P .. Flames

[Sternjaeger]

When burning fuel in the cylinder, if we're talking about an ideal process - you need exactly the same amount of fuel and air in your mixture. Since space in cylinder is limited, there is only so much air and fuel you can put in there (if we're not talking about turbo or supercharging). And certain amount of fuel requires exactly certain amount of air (I forgot the exact ratio but I can dig it up if you want, I have it one of my books).

The biggest downside of carburetors is that they can produce such ideal mixture only on certain RPMs, or RPM ranges. While direct fuel injection is much more flexible and can provide the engine with better mixture on all RPM ranges.

I am talking theory here, but I believe this is what Richie meant with:

erm... no, in a nutshell: mixture has different ratios, which need to be varied according to your altitude (leaner/richer mixture), besides a 50/50 mixture ratio would probably send your valves into orbit ;) (Disclaimer: just wanted to make a joke here, please don't take it literally and start posting copy/paste engineering blabber..)
What Richie said just doesn't make sense: engines won't produce different flames if they're direct injected or carburator injected. Or maybe I got it wrong in the first place.

[Letum]

erm... no, in a nutshell: mixture has different ratios, which need to be varied according to your altitude (leaner/richer mixture), besides a 50/50 mixture ratio would probably send your valves into orbit ;) (Disclaimer: just wanted to make a joke here, please don't take it literally and start posting copy/paste engineering blabber..)
What Richie said just doesn't make sense: engines won't produce different flames if they're direct injected or carburator injected. Or maybe I got it wrong in the first place.

I have a sneaky suspicion that Thor might know what he is talking about when it comes to engines...;)

[Sternjaeger]

I have a sneaky suspicion that Thor might know what he is talking about when it comes to engines...;)

..I bet I know a couple of things too ;)

[Sternjaeger]

well not as simple as that.

The ideal mixture is about 14:1, also called lambda=1.

But if you have certain parameters of use like
RPM
accelaration,
Airtemperature high, low
Airpressure high, low
Cold motor (less evaporating fuel in cylinder and thus richer mixture needed)

etc. etc. etc.

you get lots of changes in actual needed air to fuel ratio. Many FuelInjection Systems are a not specified to recognize all those factors, where some really complicated carburators do.

So it´s not that simple one could say:
Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions.

Amen :)

[Spinnetti]

erm... no, in a nutshell: mixture has different ratios, which need to be varied according to your altitude (leaner/richer mixture), besides a 50/50 mixture ratio would probably send your valves into orbit ;) (Disclaimer: just wanted to make a joke here, please don't take it literally and start posting copy/paste engineering blabber..)
What Richie said just doesn't make sense: engines won't produce different flames if they're direct injected or carburator injected. Or maybe I got it wrong in the first place.

ideal mixture is still basically the same at any altitude. The difference is that the air density decreases as you go up, requiring mixture adjustments to maintain the same air/fuel ratio. Some planes had auto compensation, but most did not, so mechanical tune and operator capability also come into play here.

[MD_Marx]

Well, if this colour is the result of computation alone, I think it is remarkable!
Fantastic modelling which just blows my engineering mind away.

If we are talking realism, I would say that a carburated Merlin engine starting up from cold will emit yellow flames because the mixture will be rich. After a few minutes, i would say the flame would go blu-ish?

A Daimler Benz of the period had fuel injection so i would imagine the exhausts would be blue-ish from the start as the air-fuel mixture would have been slightly leaner? Probably 'blipping' the throttle would make the burn 'leaner' as the blower increased the air flow, so it probably went bluer?

Are there any surviving RAF groundpersonnel (engine specialist) who would know? I might drop the Battle of Britain Memorial Flight a line... but it's almost a trivial detail, isn't it?

Can't wait for the game to come out, but I'd rather wait until Oleg is happy to release it, rather than rush it.

Marx

[Azimech]

well not as simple as that.

The ideal mixture is about 14:1, also called lambda=1.

But if you have certain parameters of use like
RPM
accelaration,
Airtemperature high, low
Airpressure high, low
Cold motor (less evaporating fuel in cylinder and thus richer mixture needed)

etc. etc. etc.

you get lots of changes in actual needed air to fuel ratio. Many FuelInjection Systems are a not specified to recognize all those factors, where some really complicated carburators do.

So it´s not that simple one could say:
Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions.

I'm curious which injection systems you are talking about.

The main problem with a carburetor: it's very hard to distribute the mixture to all cylinders equally. Plus fuel injected engine are less prone to icing, they have a faster throttle response and are easier to start when cold.

[proton45]

Ha ha well even with mid forties I then hope I will never become an "adult" as you put it.
Going by some posts one could drop all input, at the most only writen signs of awe are acceptable......Thank god your type is not an admin, or forums would be a dead place.

I dont think your really getting my point...lol

[T}{OR]

well not as simple as that.

The ideal mixture is about 14:1, also called lambda=1.

Almost correct. The ideal stoichiometric mixture ratio is 14,7:1 => or 15:1. When we're talking in mass, not volume.

There are two different lambdas in petrol (Otto) engines: lambda(air) & lambda(charge)*.

*not sure if this is the correct technical term in English.

In a petrol engine lambda 1 should always be constant (=1), whereas lambda(charge) can go up to 7 (with supercharged and turbocharged engines), otherwise it also equals 1.

Lambda of 1.0 is at stoichiometry, rich mixtures are less than 1.0, and lean mixtures are greater than 1.0.


Like Azimech, I am also curious of what carburetors are you talking about. The advantages of direct fuel injection over carburetors are numerous. If not, car engines would be using them even today. ;)


erm... no, in a nutshell: mixture has different ratios, which need to be varied according to your altitude (leaner/richer mixture), besides a 50/50 mixture ratio would probably send your valves into orbit ;) (Disclaimer: just wanted to make a joke here, please don't take it literally and start posting copy/paste engineering blabber..)
What Richie said just doesn't make sense: engines won't produce different flames if they're direct injected or carburator injected. Or maybe I got it wrong in the first place.

Fair enough. I forgot to write one thing - at ground level. Or even better: at 20° C & 1,013 bar (Standard atmospheric pressure: the conditions at which every engine is constructed and tested).

As for the rest (at least to my understanding, I am more into car engines), there is no such thing as 50/50 mixture. Maybe that is a phrase used by pilots and maintenance crews - they usually don't follow correct technical terms anyway. What I am trying to say (and to comment on your reply), there is an ideal ratio needed for the fuel inside the cylinder to burn most efficiently / completely (as previously mentioned). As you go higher air density is decreasing. Thus (in non supercharged engines) you need to lower the amount of fuel inside the cylinder to achieve the desired ratio or else you risk engine damage and various other things I do not want to get into now. The added downside of that is that engine power drops as well. To compensate for that - superchargers were invented. They compress air so that you can have the very same atmospheric pressure inside your cylinder as if you were flying on sea level. They can also be used to increase engine power (this is the easiest way to do it) - compress the air enough and more fuel can be put in the cylinder.

I could go on, posting diagrams, formulas etc. - but even 100 posts would be enough...

Anyway, what Richie meat was something else. With carburetors you can't get this ideal stoichiometric mixture ratio of 15:1 throughout whole RPM range because most carburetors are tuned for a certain RPM. This results in imperfect chemical reaction when fuel is burning inside the cylinder - hence probably more variable flames coming out of the exhaust, especially when changing RPM.


ideal mixture is still basically the same at any altitude. The difference is that the air density decreases as you go up, requiring mixture adjustments to maintain the same air/fuel ratio. Some planes had auto compensation, but most did not, so mechanical tune and operator capability also come into play here.

Absolutely true. What I posted above. ^^


I have a sneaky suspicion that Thor might know what he is talking about when it comes to engines...;)

I sure hope so... ;)

[W32Blaster]

My Statemant was you can´t say it that Easy: 'Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions. '
Not which Technologie is best used to gain the goal of ideal mixture under all operating conditions!



Like Azimech, I am also curious of what carburetors are you talking about. The advantages of direct fuel injection over carburetors are numerous. If not, car engines would be using them even today. ;)

Let´s say youll have a Pierburg 4A1 Carburator with ECU for fully closed loop control of a 3-Way Katalyst System and you compare it with a early k-Jet-Tronic, guess which one is more sophisticated in terms of providing right mixture for all operational state.


The main problem with a carburetor: it's very hard to distribute the mixture to all cylinders equally. Plus fuel injected engine are less prone to icing, they have a faster throttle response and are easier to start when cold.

Now youre talking about a difference between mixture is built internal Cylinder vs external like in Intake Manifold or Carburator.
As long as you are not building mixture via direct injektion you always will put extra parameters to be recognized.

[Sternjaeger]

Thor, I used the 50/50 expression cos you mentioned "half and half", sorry, nothing really technical there ;)

I have a fair experience with aviation piston engines (I was lucky enough to fiddle with 2 strokes and 4 strokes Rotax, Gypsy Major, Continental, Lycoming, P&W Wasp and lately I started to get acquainted with the RR Packard Merlin), but I am no engineer or techie, I am just a flier who's interested in knowing what's happening under the bonnet in front of his nose..

I am not entering in the merits of lambdas or mixture ratios because they're peculiar to the engines and aeroplanes (and as you said 100 posts wouldn't be enough), all I can tell you though is that yes, in theory a direct injected engine like the DB could be more "mixture efficient", although carb engines are handled according to strict parameters, so you would hardly notice any difference in the flames colouring.. if Oleg managed to implement a flame colour changing according to mixture values then this would be a boomer, cos we'd be able to adjust our mixtures by looking at the exhausts and might also be able do diagnose engine problems (i.e. red exhaust flames and sparks coming out would mean a bad, bad day.. or in case of radial engines, where the exhausts are normally connected via a ring exhaust, an intermittent flame from the main exhaust would mean misfiring cylinders etc..).

Come on Oleg, this is quality material we're delivering you here! ;)

[Oleg Maddox]

if Oleg managed to implement a flame colour changing according to mixture values then this would be a boomer, cos we'd be able to adjust our mixtures by looking at the exhausts and might also be able do diagnose engine problems (i.e. red exhaust flames and sparks coming out would mean a bad, bad day.. or in case of radial engines, where the exhausts are normally connected via a ring exhaust, an intermittent flame from the main exhaust would mean misfiring cylinders etc..).

Come on Oleg, this is quality material we're delivering you here! ;)

It is our target. Will be or not - we will see. We have a lot of such branched targets that should be done. Some are hight priority, some - not due to time that it may cost.

[T}{OR]

Thor, I used the 50/50 expression cos you mentioned "half and half", sorry, nothing really technical there ;)

I have a fair experience with aviation piston engines (I was lucky enough to fiddle with 2 strokes and 4 strokes Rotax, Gypsy Major, Continental, Lycoming, P&W Wasp and lately I started to get acquainted with the RR Packard Merlin), but I am no engineer or techie, I am just a flier who's interested in knowing what's happening under the bonnet in front of his nose..

I am not entering in the merits of lambdas or mixture ratios because they're peculiar to the engines and aeroplanes (and as you said 100 posts wouldn't be enough), all I can tell you though is that yes, in theory a direct injected engine like the DB could be more "mixture efficient", although carb engines are handled according to strict parameters, so you would hardly notice any difference in the flames colouring.. if Oleg managed to implement a flame colour changing according to mixture values then this would be a boomer, cos we'd be able to adjust our mixtures by looking at the exhausts and might also be able do diagnose engine problems (i.e. red exhaust flames and sparks coming out would mean a bad, bad day.. or in case of radial engines, where the exhausts are normally connected via a ring exhaust, an intermittent flame from the main exhaust would mean misfiring cylinders etc..).

First I would like to say how much I envy you for the described experience. I am much more into theory, calculations and various physic laws related to engines. Unfortunately I have very little time with real engines. I did say 'probably' more variable, so this means that someone who is also an engineer and has the experience should have to come here and verify this in practice.

I am though, more inclined to believe that this difference in flames is almost invisible or not noticeable when comparing them with fuel injected engines of the same era.


Come on Oleg, this is quality material we're delivering you here! ;)

Agreed. :) I see that Oleg has posted while I was writing my reply. Very nice. :cool:


My Statemant was you can´t say it that Easy: 'Fuel Injection is working better than a carburator in terms of providing the RIGHT mixture for all operating conditions. '
Not which Technologie is best used to gain the goal of ideal mixture under all operating conditions!


Alright. It may not be that easy to claim that (especially when comparing mechanical fuel injection with carburetors), there are advantages and disadvantages of both - but from technical perspective and engine development advancements (especially in todays road vehicles) direct fuel injection is light years ahead.


Let´s say youll have a Pierburg 4A1 Carburator with ECU for fully closed loop control of a 3-Way Katalyst System and you compare it with a early k-Jet-Tronic, guess which one is more sophisticated in terms of providing right mixture for all operational state.

The K-Jetronic lacks proper feedback to adjust the mixture because it doesn't have a lambda loop or lambda control. The biggest advantage of 3-Way Catalyst System (lambda control) is that engine can adjust to different types of fuel more or less automatically. It does not fix the main flaw of carburetors - inability to provide ideal mixture on all operational states.

However, mechanical injection could do only so much. Before ECU & lambda control were implemented.

Direct fuel injection coupled with specialized piston and cylinder head shapes to further improve fuel oxidation (burning) by creating swirls and tumbles (idling at low RPM even with high lambda values, up to 3.0) - is a light years ahead from any carburetor...

[Sternjaeger]

It is our target. Will be or not - we will see. We have a lot of such branched targets that should be done. Some are hight priority, some - not due to time that it may cost.

Oleg, dear old friend Oleg, if your next project was to put wings on a lawnmower I would still buy it! :grin:
You guys at Maddox delivered quality, and I know you won't ever let us down, keep up the good work guys! :)

[Sternjaeger]

First I would like to say how much I envy you for the described experience. I am much more into theory, calculations and various physic laws related to engines. Unfortunately I have very little time with real engines. I did say 'probably' more variable, so this means that someone who is also an engineer and has the experience should have to come here and verify this in practice.

I am though, more inclined to believe that this difference in flames is almost invisible or not noticeable when comparing them with fuel injected engines of the same era (see my reply to W32Blaster below).


it's a dirty business, hands always covered in grease, oil and cuts, but when you feel 1650HP growling in your guts, swinging that big propeller 10ft in front of you, 12 cylinders furiously roaring in all their power.. well it's well worth the dirty hands ;)

..The truth is that I like physics but I've always been rubbish in maths (I always lose a + or a - somewhere..).. LOL

[wildone_106]

Looks guys we want them to ship the game this decade..with all these inane requests it will never get done. You just gotta realize in the end its a simulation game..not real life. Once you come to terms with that your mind will rest...:grin:

[pencon]

I agree with Wildone,next we will be debating on what colour shoelaces the pilots wore.It's been a long enough wait for this sim and if everybody keeps going all Frazier crane on every little detail,Maddox will go broke trying to please all the anal retentives.

[T}{OR]

it's a dirty business, hands always covered in grease, oil and cuts, but when you feel 1650HP growling in your guts, swinging that big propeller 10ft in front of you, 12 cylinders furiously roaring in all their power.. well it's well worth the dirty hands ;)

..The truth is that I like physics but I've always been rubbish in maths (I always lose a + or a - somewhere..).. LOL

Now you're just talking dirty...

For me it is the other way around - I was always better in maths than in physics, but loosing a '+' or '-' is not strange to me either. :D



@ wildone & pencon: What we have been discussing here on last two pages are basics (of basics) of how internal combustion engines work. The mere fact that Oleg is considering to implement something like variable exhaust flames dependent on the mixture ratio is mind boggling. Let alone the individual cylinder modeling that has already been confirmed. Simply phenomenal work Oleg & co.


Before this gets more OT I will get back to the subject...

I wonder if the proper firing order has been simulated as well? Judging by the amount of details already shown, I would be surprised if it wasn't.

[Abbeville-Boy]

Before this gets more OT I will get back to the subject...

I wonder if the proper firing order has been simulated as well? Judging by the amount of details already shown, I would be surprised if it wasn't.

rumor is that game ships with a timing light and cloth map

[Azimech]

Let´s say youll have a Pierburg 4A1 Carburator with ECU for fully closed loop control of a 3-Way Katalyst System and you compare it with a early k-Jet-Tronic, guess which one is more sophisticated in terms of providing right mixture for all operational state.


Ah, I thought we were comparing WW2 carbs with WW2 mechanical injection. Because the Pierburg would probably have a hard time compared with Bosch Motronic, itself already 25 years old. K-Jetronic is very simple indeed.

[Richie]

erm... no, in a nutshell: mixture has different ratios, which need to be varied according to your altitude (leaner/richer mixture), besides a 50/50 mixture ratio would probably send your valves into orbit ;) (Disclaimer: just wanted to make a joke here, please don't take it literally and start posting copy/paste engineering blabber..)
What Richie said just doesn't make sense: engines won't produce different flames if they're direct injected or carburator injected. Or maybe I got it wrong in the first place.

I don't really explain things very well. I think that fuel injection is a much more precise system than a carbureted engine and much less likely to flame up when being started. In all of the videos I've watched of 109s being started not once have I seen one have a stack fire. That's why I said I thought the Allied pilots will have more fun with the flames and over priming than the Germans will. Does that make sense? Put BF 109 in youtube and watch 109s start.

[sorak]

I agree with Wildone,next we will be debating on what colour shoelaces the pilots wore.It's been a long enough wait for this sim and if everybody keeps going all Frazier crane on every little detail,Maddox will go broke trying to please all the anal retentives.

Did you forget that Oleg himself requested the community to talk about this subject? Post like yours is the useless ones.

[Richie]

Well it really doesn't really matter if we go over board because he can pick and chose what information he can use and what he likes right?

[Luftwaffepilot]

Hopefully we get some nice christmas special friday update with release date, publisher name, awesome effects video and more. :grin:
I can't wait.

[ElAurens]

it's a dirty business, hands always covered in grease, oil and cuts, but when you feel 1650HP growling in your guts, swinging that big propeller 10ft in front of you, 12 cylinders furiously roaring in all their power.. well it's well worth the dirty hands ;)

..The truth is that I like physics but I've always been rubbish in maths (I always lose a + or a - somewhere..).. LOL

Never been into an aero engine, but I work on lots of old stuff. Everything from a Model T Ford to E-type Jaguars and a Lotus 11 LeMans.

Actually, driving the very early cars has much in common with early aircraft. The carbs are very rudimentary, as are all the other systems. They require constant input from the operator to be at their peak. Every gross change in throttle setting demands a change in mixture and spark advance, and it all changes as the engine warms. The settings you left the shop with will not be the settings you come back with.

It's a type of driving I really enjoy as it requires actual thought and input.

[334th_Gazoo]

These are my thoughts as a steel fabricator. Using an oxygen acetylene cutting torch as an example... A very rich mixture of gasses coming out of the torch is Orange with much Black smoke. A high oxygen mixture is Blue White.Setting the mixture At the optimal point between an Oxidising flame and Carburizing flame is ideal.

I believe that effciency in an engine may be measured thus, and exhaust coulor be matched accordingly.

Thankyou for your patience

334th_Gazoo

The point is.. Is it running Lean or Rich?

[WTE_Galway]

Carby mixture settings have nothing to do with the stack flames on startup.

Carburetor aircraft engines commonly have a hand priming pump like the one below out of a spitfire:

http://www.spitfirespares.com/spitfirespares.com/Website%20products%20143/K%20Gass%201940%20small.jpg

The pump injects fuel directly into the carb barrel or intake manifolds. Pumping it too many times before cranking the engine results in an excess of fuel and exhaust stack flames can result.

[Richie]

These are my thoughts as a steel fabricator. Using an oxygen acetylene cutting torch as an example... A very rich mixture of gasses coming out of the torch is Orange with much Black smoke. A high oxygen mixture is Blue White.Setting the mixture At the optimal point between an Oxidising flame and Carburizing flame is ideal.

I believe that effciency in an engine may be measured thus, and exhaust coulor be matched accordingly.

Thankyou for your patience

334th_Gazoo

The point is.. Is it running Lean or Rich?


Right. If you look at all of the engines in the videos...in they dark... they're all blue. By the chart that was put up if the mixture is right and the engine is running perfectly the flame should be blue with a lick of red at the end. If you stood right up close maybe you could see some red.

http://www.youtube.com/watch?v=QhFAwSk9Vqg&feature=player_embedded


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


http://www.youtube.com/watch?v=4ZzvKCQwWj0

[T}{OR]

Ah, I thought we were comparing WW2 carbs with WW2 mechanical injection. Because the Pierburg would probably have a hard time compared with Bosch Motronic, itself already 25 years old. K-Jetronic is very simple indeed.

True. We should compare the same engines of the era. I've updated my reply two pages back.

[ATAG_Dutch]

It is our target. Will be or not - we will see. We have a lot of such branched targets that should be done. Some are hight priority, some - not due to time that it may cost.

Sorry Mr Maddox, but does that mean that you'll take the members advice and make exhaust flames blue?
As there is no evidence at all for yellow flames?
Thanks.

[WTE_Galway]

Sorry Mr Maddox, but does that mean that you'll take the members advice and make exhaust flames blue?
As there is no evidence at all for yellow flames?
Thanks.

How did you get that?

The reply you quoted was related to a question about modeling individual cylinders in an engine to get authentic simulation of misfires etc .

[JG52Krupi]

Sorry Mr Maddox, but does that mean that you'll take the members advice and make exhaust flames blue?
As there is no evidence at all for yellow flames?
Thanks.

There is evidence of yellow flames on startup and also if the mixture is incorrect...

[Sutts]

There is evidence of yellow flames on startup and also if the mixture is incorrect...

Yellow flames on startup..agreed.

Yellow flames from running engine...please point me to this evidence, I must have missed it.

Thanks

[TheGrunch]

Sorry Mr Maddox, but does that mean that you'll take the members advice and make exhaust flames blue?
As there is no evidence at all for yellow flames?
Thanks.
We also have no evidence one way or the other for a running engine with longer exhaust stacks installed, as the Spitfire Mk. I has. All of those videos depict engines with very short exhaust stacks; Like so:
http://www.williammaloney.com/Aviation/CanadianWarplaneHeritageMuseum/SupermarineSpitfireMkIX/images/11RollsRoyceMerlinExhaustStacks.jpg
Instead of like so:
http://www.hyperscale.com/2007/features/images/Spit_6.JPG

[pateador]

I've been working with planes and, at least in the case of radial engines, I still remember how amazed I was the first time I watched a ground test at night : the flames at full power are definitively white with a blueish end ( with the carburator and ignition tuned properly ) and they extended more than half the fuselage!!! ( the plane was a biplane used for cropdusting, with radial engine and one exhaust stub by the right side ) to give you and idea try to find pictures of Hurricanes used as night fighters... they had to add an anti-glare panel just ahead of the cockpit, and the streaking extends beyond the cockpit ...

[fireflyerz]

Again, very interesting flame patterns / colours on rpms on this meteor ...

http://www.youtube.com/watch?v=D7WS5La_Av8&feature=related


Also interesting LACK of flame on this merlin, packard I presume, fuel types on both vids...who knows.
http://www.youtube.com/watch?v=-mQRJA5W8CI

[BadAim]

Wow, this thread is hilarious! The whole thing has been explained several times and still people argue about nothing. It makes me glad that I've decided to spend much less time here. See you on Friday, Oleg.

[Sternjaeger]

this is no CSI, no evidences available, only the laws of physics ;)

Once again, we need to make a distinction between startup backfire and exhaust flames:

1) on a cold engine, backfire happens for overpriming/bad magnetoes not delivering regular sparks at low revs; on a hot engine, it happens for the same conditions of a cold engine plus the hot exhausts/outlet valves/combustion chamber/carbon residues, who can ignite the non burnt mixture. In both cases the result will be a "cold flame"(as in relatively low temp flame) which will roar out of the exhaust (and warm up the combustion chamber a bit!) in a spectacular fashion. Backfire is more dangerous on radial engines because the flames can linger in the exhaust ring outlet and pre-ignite the mixture in the combustion chambers (blowing up cylinders/valves/spark plugs).

2) exhaust flames are the result of a correct combustion in the chamber, and because of the temperatures and pressures involved, they come out as hot flames normally (blue flames).

If you have the movie Tora Tora Tora have a look at the carrier takeoff sequence to see a good examples of blue flames in action.

[Sternjaeger]

Again, very interesting flame patterns / colours on rpms on this meteor ...

http://www.youtube.com/watch?v=D7WS5La_Av8&feature=related


Also interesting LACK of flame on this merlin, packard I presume, fuel types on both vids...who knows.
http://www.youtube.com/watch?v=-mQRJA5W8CI

this is perfect example of a badly maintained RR (the former, whose owner/operator should be slapped in the face...repeatedly..with a big spanner...) and an engine who's heavily modified (that's Strega from the Reno Races) and maintained to perfection.

[JVM]

this is perfect example of a badly maintained RR ...

Yes, sure, but keep in mind this a Meteor tank engine, derivated from a, but not a Merlin! So it is easy to imagine it was not that well maintained for a track vehicle use, that it may have had a much harsher life than an aero engine, and also the sparking system is different etc etc...
Besides it is running on a bench just for fun, driven by UK amateurs which are not swimming in money like the Strega people...

So please, a bit of moderation would not be out of place...

JV

[robtek]

One can clearly see that No.5 Cylinder on the left side and first No. 2, 3 and 4 then only No. 3 Cylinder on the right side have a different exhaust flame (red-orange vs blue-white).
Later the different exhaust temperatures are clearly seen.

[Osprey]

That Seafire vid has a single yellow burst from each cylinder then it all went blue. I think there's evidence enough on here for Oleg to get it right.

[Richie]

Just to be accurate I'd stay away from any race aeroplanes. God knows what they're using in those things to make them haul *ss like that..nitros, alcohol. They're forever blowing engines in those races.


http://www.youtube.com/watch?v=0vniz3zXf4g

[Sternjaeger]

Yes, sure, but keep in mind this a Meteor tank engine, derivated from a, but not a Merlin! So it is easy to imagine it was not that well maintained for a track vehicle use, that it may have had a much harsher life than an aero engine, and also the sparking system is different etc etc...
Besides it is running on a bench just for fun, driven by UK amateurs which are not swimming in money like the Strega people...

So please, a bit of moderation would not be out of place...

JV

Well yes, the thing is not the same, pistons were casted instead of milled, components were made of heavier alloys etc.. but the engine would still run fine.
If you love engines you don't run them "just for fun", because one day they'll get rare and then who's gonna have fun? The engine is obviously not well carbureted, besides giving it a sudden revving just to have some flames spurting out is just plain stupid.. that engine could be used in a tank restoration, and not as some "fun toy".

Sorry if my opinion is offending you mate, but hey guess what, we live in a free world... :rolleyes:

[Sternjaeger]

Just to be accurate I'd stay away from any race aeroplanes. God knows what they're using in those things to make them haul *ss like that..nitros, alcohol. They're forever blowing engines in those races.


yep, nitrogen, ethanol, water injection.. you name it!

[Abbeville-Boy]

oleg loves yellow because it is 1c company color
exhaust will stay yellow :grin:

[Insuber]

oleg loves yellow because it is 1c company color
exhaust will stay yellow :grin:

ROTFL!

BTW, 30 pages on the color of exhaust flames ... a detail of an isolated short event ... OMG! Your monkey is really really bad guys ... :D

[Necrobaron]

BTW, 30 pages on the color of exhaust flames ... a detail of an isolated short event ... OMG! Your monkey is really really bad guys ... :D

Not sure why people make comments like this. Oleg specifically asked for input and he got it.:confused:

[winny]

Not sure why people make comments like this. Oleg specifically asked for input and he got it.:confused:

I think it was a joke... And he has a point. Relax.

[Richie]

I think everyone did well on this subject. If it went overboard that's ok I guess because it doesn't really matter. Like someone said no information is bad information. I'm sure Oleg has what he want's somewhere in all of this. There's a lot of flames and planes in here ...that almost rhymes.

[winny]

It's been an interesting thread from the start.

And you can never have too many videos of Merlins.

The general consensus seems to be yellow at startup turning blue (all things being well) a few seconds later.

It will be interesting to see Olegs interpretation.

[BP_Tailspin]

I thought everyone might enjoy these fiery pictures.

Not posting for the game, but real never the less … the spitting fire is caused by over priming, the raw fuel is spit from the exhaust, hence the name “spitfire”

http://www.cubpilot.com/Tspin/spit1.jpg

http://www.cubpilot.com/Tspin/spit2.jpg

http://www.cubpilot.com/Tspin/spit3.jpg

OK we all know the little fighter was really named after a girl named Ann but the spitting fire makes for a better story.

Thanks for posting the Friday updates Oleg, I’m sure you will pull the information needed from all the replies, looking forward to SoW Battle of Britain.

[Necrobaron]

I think it was a joke... And he has a point. Relax.

Oh, I'm relaxed. I guess I missed the joke or the point.

[winny]

Oh, I'm relaxed. I guess I missed the joke or the point.

Yeah.. it was the smiley face that gave the joke away and the 310 replies that make the point.

[ATAG_Dutch]

How did you get that?

The reply you quoted was related to a question about modeling individual cylinders in an engine to get authentic simulation of misfires etc .

Precisely. Discussion was invited regarding flame colour being too yellow in the shot. Everyone says 'should be blue'. We don't as yet appear to have a response to this.

[Insuber]

Not sure why people make comments like this. Oleg specifically asked for input and he got it.:confused:

Necrobaron,

It was a bit of humour among pages and pages of scientifical dissertations. Maybe in your culture humour works differently, apologies in that case. BTW your sentence "Oleg specifically asked for input and he got it" is a great piece of humour to my eyes, bravo!

Insuber

[Sternjaeger]

Precisely. Discussion was invited regarding flame colour being too yellow in the shot. Everyone says 'should be blue'. We don't as yet appear to have a response to this.

..erm, what kind of response do you need exactly? From Oleg? :confused:

[Baron]

..erm, what kind of response do you need exactly? From Oleg? :confused:


Was kind of the point of this update, oleg asked a question, a majority of posters awnsered another q (that was never asked btw) instead and we havent seen him since.(exept for a few posts by oleg in the beginning)

[Sternjaeger]

Was kind of the point of this update, oleg asked a question, a majority of posters awnsered another q (that was never asked btw) instead and we havent seen him since.(exept for a few posts by oleg in the beginning)

....so? I don't understand what's the problem with it... does he HAVE to? C'mon guys, if you haven't understood how the guy works by now I reckon u r hopeless in judging characters ;)

...and please, I just used a thing called sarcasm, don't take it personally...

[Baron]

....so? I don't understand what's the problem with it... does he HAVE to? C'mon guys, if you haven't understood how the guy works by now I reckon u r hopeless in judging characters ;)

...and please, I just used a thing called sarcasm, don't take it personally...


No, he absolutly does not. Thinks some mean the threadh have surved its purpose (or not) thats all. ;)

[Necrobaron]

Necrobaron,

It was a bit of humour among pages and pages of scientifical dissertations. Maybe in your culture humour works differently, apologies in that case. BTW your sentence "Oleg specifically asked for input and he got it" is a great piece of humour to my eyes, bravo!

Insuber

No apologies needed! I sometimes think humor/sarcasm is hard to detect on a message forum.;)

[ElAurens]

Truth!

[nearmiss]

It always amazes me

How much verbiage posters can create about practically nothing.

Flame colors from exhausts... Oleg got enough from the first day of postings I'd say.

Sometimes I think Oleg is just making a joke and members don't get it.

[SlipBall]

It always amazes me

How much verbiage posters can create about practically nothing.

Flame colors from exhausts... Oleg got enough from the first day of postings I'd say.

Sometimes I think Oleg is just making a joke and members don't get it.



Well he like's to keep us busy:-P

[JAMF]

Well he like's to keep us busy:-POr it could be easier to ask people to give the proof of how it was and do the research in advance for you, than change it all again afterwards. ;)

[julian265]

Sometimes I think Oleg is just making a joke and members don't get it.

Like a thread for "FAQ-QUESTIONS,release date,system specs, for SOW" ?

Also, sarcasm doesn't show through text well... Unless it's really obvious or the reader knows the poster well.

IMO ...
"Effect of exhaust flame at night time. Emulation of each cylinder exhaust in relation to emulation of real engine cylinders work by a program.
My question to community: isn't it too yellow? Maybe to add a bit red color in a mix with yellow? It is tunable really, so I would like to listen suggestions"
... is not a joke. Suggestions were asked for and provided, in this case the desire for an official response is far more justified than to a query buried in any usual thread full of speculation.

[ElAurens]

And now the thread will proceed another 10 plus pages with us arguing weather or not all the info provided was really necessary, and what Oleg wanted.

LOL!!!!

You guys really need to relax.

[WTE_Galway]

Precisely. Discussion was invited regarding flame colour being too yellow in the shot. Everyone says 'should be blue'. We don't as yet appear to have a response to this.

lots of response

the consensus was:

- yellow when its a stack fire from over priming (priming pumps raw fuel into the inlets) and

- blue in a running engine though you wouldn't normally see the blue in daylight


though there was some confusion between overpriming flames and a running engine followed by a lot of interesting but off topic stuff about fuel mixtures

[Old_Canuck]

Interestingly, Oleg's question kept this thread on topic for the most part. Now in a few hours we can chase each other's tails over another topic.

[Rodolphe]

...

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


I'm sure you have, Thanks !



Feed back on the Spitfire 3D model :
Some of us have probably noticed this particularity of the generator air scoop on the portside of the engine cooling.

http://users.teledisnet.be/web/mfe39146/GenIntake1.jpg
http://users.teledisnet.be/web/mfe39146/GenIntake.jpg


...

[swiss]

Are you sure you couldn't find a misplaced rivet as well?

[Flanker35M]

S!

Swiss, the flight sim horde is the most picky race in world of gaming ;) Also if you look at the exhaust stacks they are not the same shape as in Rodolphes pic ;) J/K..I bet that detail is easy to fix quickly.

[Pierre@]

Are you sure you couldn't find a misplaced rivet as well?

I am sure he could! And I trust him to find them ;)
Thanks Rodolphe.

[Sternjaeger]

...


Some of us have probably noticed this particularity of the generator air scoop on the portside of the engine cooling.
...

..some of us without a life, that's what my gf would say :rolleyes:

Hey don't blame me, she was around while I was posting this!! ;)

[Rodolphe]

...

I am sure he could! And I trust him to find them ;)
Thanks Rodolphe.


:grin: Pierre@


You know Pierre, riveting is a interresting job but fabric seam has preference ! :grin: :grin:

http://users.teledisnet.be/web/mfe39146/Fabric.jpg


...

[ATAG_Dutch]

the consensus was:

- yellow when its a stack fire from over priming (priming pumps raw fuel into the inlets) and

- blue in a running engine though you wouldn't normally see the blue in daylight


though there was some confusion between overpriming flames and a running engine followed by a lot of interesting but off topic stuff about fuel mixtures

Yes indeed and I agree with the consensus.

My point was that Mr Maddox responded directly to the very interesting but slightly off topic post from Sternjaeger about different colours for different mixtures as being a target for the future.

If different colours for different mixtures is a target for the future, the inference is that yellow, with or without a little more red, is currently the default colour for all mixture settings.:(

[Sternjaeger]

Yes indeed and I agree with the consensus.

My point was that Mr Maddox responded directly to the very interesting but slightly off topic post from Sternjaeger about different colours for different mixtures as being a target for the future.

If different colours for different mixtures is a target for the future, the inference is that yellow, with or without a little more red, is currently the default colour for all mixture settings.:(

Dutch, the point I made was not as off topic as you might think, it's all related to the game engine features. In order to address a question you need to look at all its aspects, so then the case is closed. Brainstorming over a concept is always good material for developers; jibber jabber, moaning and rants on the opposite, are not productive, but unfortunately I see many of these happening here sometimes, maybe that's what puts Oleg out so much.. I remember the very early days of IL-2 Sturmovik, and Oleg was way more active, but I guess that years of rants have worn his patience out..

[ATAG_Dutch]

Dutch, the point I made was not as off topic as you might think, it's all related to the game engine features. ..

Don't get me wrong Stern, I did say 'slightly off topic', your posts in this thread have been very interesting for me. :)

As regards a response from Mr Maddox, given the amount of information in the thread, a simple 'ok guys, we'll change the default to blue' would have been appreciated.

Some months ago, there was a question surrounding the colour of RAF squadron codes, which resulted in 'ok guys I guess we should change the default from white to grey' from Luthier.

It'd be nice to find out what the response on this issue is, is all.;)

[Sternjaeger]

Don't get me wrong Stern, I did say 'slightly off topic', your posts in this thread have been very interesting for me. :)

As regards a response from Mr Maddox, given the amount of information in the thread, a simple 'ok guys, we'll change the default to blue' would have been appreciated.

Some months ago, there was a question surrounding the colour of RAF squadron codes, which resulted in 'ok guys I guess we should change the default from white to grey' from Luthier.

It'd be nice to find out what the response on this issue is, is all.;)

hehehe I know, what you mean, but I want to hope that Oleg is busy making the magic happen ;)

[speculum jockey]

hehehe I know, what you mean, but I want to hope that Oleg is busy making the magic happen ;)

I don't think that Oleg's sex life is any of our business.

[Foo'bar]

I don't think that Oleg's sex life is any of our business.

In german there's a saying: "Die Meldung entsteht beim Empfänger."

;)

[Wutz]

In german there's a saying: "Die Meldung entsteht beim Empfänger."

;)
Ist das nicht eine Umschreibung für das Siemens "Bananen-Produkt" "Es reift beim Kunden" :lol:

[ATAG_Dutch]

In german there's a saying: "Die Meldung entsteht beim Empfänger."

;)

Was können wir erwarten? Ist er nicht eine gynaecologist? :rolleyes::grin:

[Insuber]

Pitié !!!!!!!!!

[nearmiss]

Off topic appears to prevail.

This thread is closed.