New afterburner cone

[some1]

hmmm... download doesnt work ...any mirrors for it ?

 

Strange, works for me..

 

Anyway, it's avaliable now at lockonfiles.com

[komarov]

The afterburner is a difficult, but not a mystical thing.

The colour of the flame, lenght of the flame, the width of the flame, the number of the shockwave rings, are came from the main parameters of the engines, and the atmospherical conditions.

 

Look the differences of F-15C - F-15E.

Basicly the F-100PW100/200/220 and the PW229 is same, but the PW229 has an improved afterburner, more specific fuel consumption, higher fuel eater system, so the flame lenght, ring numbers is different.

Check every pic from Lakenheath.

The numbers of the rings at the F-15C are six or seven, but at the Strike Eagle are nine to ten.

Or look the MiG-29.

In daytime the flame is almost invisible, or we can see 3-4 rings.

In low level at slow speed, but darker background we can see 4-5 rings, but if we check the high altitude pictures, we find a longer 6-7 rings more blue tone flame.

Why? Because, the plane fiy at high altitude, lower pressure atmosphere, and the nozzle pressure ratio is higher than the see level.

 

Check the Su-27 family.

The flame lenght is almost long like the famous afterburner of the MiG-23, the ring number is higher than 9, the sound is a nice mixture of the deep earthquake like Viggen, because this engines use a big airflow compressor, 115 kg/sec air, but the thin and long flame produce the very special, high frequency noise.

 

Yes, my absolute amateur opinion, the sound of the flame is build by next parameters.

 

The higher ring numbers produce the higher frequencies, SR-71 was the winner.

The wider flame came from higher fuel consumption, and higher airflow, the higher width produce the deeper sound.

Viggen is the winner, but the absolute winner is the Tu-160.

 

The amplitude of the noise and the distance between the rings have some connection.

 

If the nozzle pressure ratio (high altitude-low air pressure, or low altitude high speed pass-nor,al air pressure) goes higher, the distance of the rings, and the whole flame lenght are goes longer.

 

Bye

[Corsair7662]

the long one is definitally more realistic! i sure hope the smaller cones are from a lower throttle percent because if not something is really wrong. the F-15 has a full AB cone of about 15-30 feet, as for the one of the tomcat I provided will represent it as 40 feet and over :).

[Merlin555]

great ! thx a lot !

 

[fragal]

:D Rep inbound! gr8 work, glad i checked back now :thumbup:

[Glowing_Amraam]

Hm... i cant get it to work??? I install it with Modman, but im still seeing the damn crappy old one :P

[Glowing_Amraam]

And is it just me, or is the cone "bent" a little downwards?

[Glowing_Amraam]

Nevermind, got it to work :D

[Kuky]

Thank you Some1 :D

[Corsair7662]

I like what I did to mine, changed the color and changed the original cone circles to something better.:) I dislike the short one that is way unrealistic, the extra long is more real but mine has a normal realistic length and nice output display. I combined two different files together and I like the result basically :P.

[komarov]

I think your pictures are really good!!!

[komarov]

Not this pictures.

The F-14 and Su-27 pictures are unrealistic.

Too long flames.

Looks like an SR-71's flame...

[Corsair7662]

So you mean to say these arent realistic?

 

Yeah the ones in LOMAC get thinner as they get bigger but they look real to me!

[komarov]

No.

But it's a high altitude, longer flame.

The flame lenght is 3/4 long as the plane.

Check the point of view.

 

And check this photos:

 

http://forum.airforce.ru/download.php?id=2888

 

http://forum.airforce.ru/download.php?id=2895

 

http://www.myaviation.net/search/photo_search.php?id=00892887&size=large

 

http://www.myaviation.net/search/photo_search.php?id=00760772&size=large

 

http://www.myaviation.net/search/photo_search.php?id=00655003&size=large

 

http://www.myaviation.net/search/photo_search.php?id=00183757&size=large

 

and F-14D:

 

http://www.myaviation.net/search/photo_search.php?id=00149899&size=large

 

http://www.myaviation.net/search/photo_search.php?id=00149898&size=large

 

http://www.myaviation.net/search/photo_search.php?id=00149622&size=large

 

especially the last one.

9-10 rings, 3/4 plane long flame.

On your picture, the altitude was high, the sky was dark.

[Corsair7662]

No.

But it's a high altitude, longer flame.

The flame lenght is 3/4 long as the plane.

Check the point of view.

 

especially the last one.

9-10 rings, 3/4 plane long flame.

On your picture, the altitude was high, the sky was dark.

 

haha!, alright.

the amount of altitude has only a little to do with the size of the cone other than the throttle percentage. From the two pics I have an example of, one at high alt and one at low alt on a carrier deck, their about the same size arnt they? So how does altitude affect the thrust output quantity? Yes I know high altitude is refered to as "Density Altitude" but it doesnt change the amount of throttle the engines are running at. I guarantee you if ya look at those pictures of those planes at a darker environment, you would see they are all large. But like that Su-27 for example, he is only at about 85% and he could really crank it up if he wanted. The size of the afterburner cones also reflect the quality of how well the fuel is being burned. Look at the Strike Eagle in your picture to the F-15 in LOMAC and their nozzles, they look just the same as if it was at "Idle" but once you crank it up to 90%+ the nozzles change and get larger.

[EscCtrl]

Its not the length thats unrealistic - look at the pictures in real life - notice how the afterburner jet is curved and not a simple cone shape and the colour gradually fades out rather then being a distinct shape all the way through

 

thats why it might not look right - not sure if much can be done about it though

[komarov]

"So how does altitude affect the thrust output quantity? Yes I know high altitude is refered to as "Density Altitude" but it doesnt change the amount of throttle the engines are running at."

 

Thrust, altitude, flame lenght. What is the connection? The nozzle pressure ratio.

At high altitude, the flame is longer than at low level.

If the throttle at full reheat, the nozzle goes larger, but NEVER opening full diameter, because the hydraulic system is working allways again the nozzle pressure. If an engines stopped, the nozzle's hydraulic system lost the pressure, the nozzle is opening full diameter. When you starting an engine, for the better startup time and condition, the nozzle leave full open position until the RPM stabilized at 30-40%. Closeing to smallest diameter above this RPM and hold this position to 100%.

If you use the afterburner, the RPM in lot of plane goes higher than 100%

103-108 percent for the stabil gas flow again the afterburner enormous pressure.

 

If the plane goes higher, the nozzle perssure ratio goes higher, because the atmospheric pressure is going down.

If the plane doesn't change the altitude, but goes faster, the dinamic compression in the air intake/tunnel goes higher, the whole engine pressure ratio goes higher, the airflow goes higher, the fuel pumps produce more fuel to the afterburner.

The main thrust levels:

-Static dry and afterburner thrust on break pod or test pod

-Static dry and afterburner thrust on sea level zero speed in the plane

-Dynamic dry and afterburner thrust low altitude at Mach 0.8-0.9 in the plane

-Dynamic dry and afterburner thrust low altitude at ~ Mach 1.2 in the plane

-Dynamic dry and afterburner thrust high altitude at Mach 0.8-0.9 and max speed, of course in the plane.

 

and on your two F-14 pic, we can see two different types of Tomcat, the first is an F-14D with GE engine, higher thrust, F-100GE400, and the take off pictures show an F-14A with a lower thrust Pratt&Wittney TF-30P412, it's a total different engines, with total different parameters.

[Vekkinho]

Hello,

 

nice looking cones but how's FPS with that?!

[Vekkinho]

AFAIK, there are 3 AB stages simulated in LO and FC.

 

So why don't you make short one for the first stage, medium for 2nd, and Extremely long as a flat out AB?!

 

Can it be done?

 

Real AC have more AB travel than what's presented in 1.12a.

Remember how we could place RPM to a 110% back with 1.02. That's real but what we now have is a 103-104% RPM maxed. It's true but there's RPM override for extreme situations in real life. At least with MiG-29.:pilotfly:

[Corsair7662]

"So how does altitude affect the thrust output quantity? Yes I know high altitude is refered to as "Density Altitude" but it doesnt change the amount of throttle the engines are running at."

 

Thrust, altitude, flame lenght. What is the connection? The nozzle pressure ratio.

At high altitude, the flame is longer than at low level.

If the throttle at full reheat, the nozzle goes larger, but NEVER opening full diameter, because the hydraulic system is working allways again the nozzle pressure. If an engines stopped, the nozzle's hydraulic system lost the pressure, the nozzle is opening full diameter. When you starting an engine, for the better startup time and condition, the nozzle leave full open position until the RPM stabilized at 30-40%. Closeing to smallest diameter above this RPM and hold this position to 100%.

If you use the afterburner, the RPM in lot of plane goes higher than 100%

103-108 percent for the stabil gas flow again the afterburner enormous pressure.

 

If the plane goes higher, the nozzle perssure ratio goes higher, because the atmospheric pressure is going down.

If the plane doesn't change the altitude, but goes faster, the dinamic compression in the air intake/tunnel goes higher, the whole engine pressure ratio goes higher, the airflow goes higher, the fuel pumps produce more fuel to the afterburner.

The main thrust levels:

-Static dry and afterburner thrust on break pod or test pod

-Static dry and afterburner thrust on sea level zero speed in the plane

-Dynamic dry and afterburner thrust low altitude at Mach 0.8-0.9 in the plane

-Dynamic dry and afterburner thrust low altitude at ~ Mach 1.2 in the plane

-Dynamic dry and afterburner thrust high altitude at Mach 0.8-0.9 and max speed, of course in the plane.

 

and on your two F-14 pic, we can see two different types of Tomcat, the first is an F-14D with GE engine, higher thrust, F-100GE400, and the take off pictures show an F-14A with a lower thrust Pratt&Wittney TF-30P412, it's a total different engines, with total different parameters.

 

Your finally getting somewhere!:smilewink:

 

@Vekkinho - my FPS is great!

[komarov]

The RPM at 103-108% (smaller for low pressure shaft, higher for high pressure shaft) are not an override.

This is a normal regime, as I said, this is for the stabil gas flown in the engine at max reheat.

[F l a n k e r]

Thrust, altitude, flame lenght. What is the connection? The nozzle pressure ratio.

At high altitude, the flame is longer than at low level.

If the throttle at full reheat, the nozzle goes larger, but NEVER opening full diameter, because the hydraulic system is working allways again the nozzle pressure. If an engines stopped, the nozzle's hydraulic system lost the pressure, the nozzle is opening full diameter. When you starting an engine, for the better startup time and condition, the nozzle leave full open position until the RPM stabilized at 30-40%. Closeing to smallest diameter above this RPM and hold this position to 100%.

If you use the afterburner, the RPM in lot of plane goes higher than 100%

103-108 percent for the stabil gas flow again the afterburner enormous pressure.

 

You tell it very well!

The nozzle pressure ratio is the ratio between the exhaust pressure and the external pressure. In normal conditions the nozzle is adapted to the external pressure, so the pressure ratio is one, but when the pilot use the afterburner, the nozzle opens up, making those characteristic disks, called Mach disks, a shock wave recompression. I found this in the web: http://www.aerospaceweb.org/question/propulsion/q0224.shtml

[komarov]

Thank you for this link.

Very interesting.

As we see, the mach disk are the inner part of the flame, but the flame outer part is a limiter wave.

So in our game, the best approach, the best way is the two ring flame version.

If we look an afterburner takeoff, we see a vibration in the nozzle, we see a really fast vibration of the limiter wave in the outer part of flame, and the huge blur of heat.

But the mach disk almost stabil, moveing only forward-backward little when the fuel injection are changed. (throttle positon are changed).

[komarov]

http://www.voodoo.cz/tomcat/info.html

the main differences between the two Tomcat-engine

 

http://www.f-111.net/images/6sqntestcell.jpg

it's an F-111's TF-30, with a little bit different construction, and smaller thrust.

But in the F-14A the thrust was 93kN and in the F-111F was (or is, because now it's the C version in the australian AF) 112kN.

 

http://www1.ezbbs.net/01/viperkbt/img/1151498973_1.jpg

 

And the main problem with this model is the too many and too thin flaps around the nozzle.

[Rhen]

Nice work on the burner flame.

 

 

One of the things that I'd like to see is increasing visibility for the afterburner flame. If it's dark, you can spot aircraft using their afterburners for MILES! You can see an afterburner flame for more than 20 NM. We even hit the burners to help affect a timely rejoin when we've been split up while fighting, etc. It would be nice to see a very visible afterburner effect that could be seen for at least 10 NM - hell, I'd even be happy with just 5.