J-20... The New Generation Fighter
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Re: New Generation Fighter
is garrette air intake same as CARTE airintake adapted by F-22 and F-18C?
is garrette air intake same as CARTE airintake adapted by F-22 and F-18C?
Re: New Generation Fighter
Actually, I've been giving adjustable DSI inlets a bit of thought as of late. The DSI essentially uses a bump to block off chaotic airflow at supersonic speeds (I believe the term is boundary layer separation) and slowdown and smooth out this airflow before it reaches the engine (otherwise the engine would stall). There should be a certain speed limit to an aircraft with a DSI because as the plane flies faster airflow gets more chaotic and the boundary layer (the airflow) increases to a point where the bump can no longer block or smooth it. Being able to adjust the bump or adjusting the inlet should help increase airflow when that happens. I think maybe the article is indicating the reverse process, where they DSI is designed to block the boundary layer at higher speeds, making it worse for low speeds, which means adjusting the inlet to allow more air. However, I don't know if this is exactly how it works (not an expert), or if it's using both to compress air like you said.
Re: New Generation Fighter
Those ramps, diverters, bumps prevent turbulent airflow that exists right next to the skin of the airframe from entering the engine to allow for a smooth combustion process, as stated.
The geometry of the intake also slows the airflow down and already increases pressure. That slowdown process is especially important at supersonic speeds, since air arriving at the blades with that speed could do severe damage.
Normally, top speeds for airplanes with non adjustable intakes are close to Mach2. Anything faster will need variable geometry inlents to adjust for the wide variaty of conditions experianced.
For planes with a fixed inlet, I'd exspect it to be designed for optimal engine performance at tactical airspeed, around 400 to 500knots I guess.
It may, however, make sense to allow the intake to open up in some way during take off and landing for increased performance in these flight regimes.
Those ramps, diverters, bumps prevent turbulent airflow that exists right next to the skin of the airframe from entering the engine to allow for a smooth combustion process, as stated.
The geometry of the intake also slows the airflow down and already increases pressure. That slowdown process is especially important at supersonic speeds, since air arriving at the blades with that speed could do severe damage.
Normally, top speeds for airplanes with non adjustable intakes are close to Mach2. Anything faster will need variable geometry inlents to adjust for the wide variaty of conditions experianced.
For planes with a fixed inlet, I'd exspect it to be designed for optimal engine performance at tactical airspeed, around 400 to 500knots I guess.
It may, however, make sense to allow the intake to open up in some way during take off and landing for increased performance in these flight regimes.
Re: New Generation Fighter
I think these components can have more than one function.
Sounds correct.
I think when the plane flies slower, the inlet has to increase to let in more air to keep the boundary layer intact and enough air for combustion. Because flow separation occurs more readily at lower speed and low density. And when it flies faster, the inlet has to reduce the airflow speed to prevent stalling as you said and damage to compressor blades as scratch said.
Yes, at low speed the engine needs to work harder to suck in air if the inlet is small.
I think these components can have more than one function.
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Re: New Generation Fighter
I must thank latenlazy, Scratch, and Maxx for your excellent analysis! This makes sense now to a certain extent. Take a look at what huzhigeng said:
What are some other benefits to adjustable intakes besides modulation of air flow at different airspeeds? I didn't know what huzhigeng was referring to when he said "Killing two birds with one stone" (Chinese equivalent, anyways).
I must thank latenlazy, Scratch, and Maxx for your excellent analysis! This makes sense now to a certain extent. Take a look at what huzhigeng said:
What are some other benefits to adjustable intakes besides modulation of air flow at different airspeeds? I didn't know what huzhigeng was referring to when he said "Killing two birds with one stone" (Chinese equivalent, anyways).
Re: New Generation Fighter
It might be more than "two birds" actually. It's probably easier to control return signatures using a DSI (The bump blocks the fan so the Airframe doesn't require a significant S-Shape) and it may offer a weight reduction by taking out a lot of complex moving parts inside the intake. However, because the intake itself is variable, this weight reduction might not be that significant.
Re: New Generation Fighter
Maybe through something similar to this? :
In the pic you can see the first plane has a scoop like thing on the DSI intake. If that scoop can be extended and retracted around the DSI bump you get a opening with varying cross section area.
Something similar may be possible for side intakes.
Just my guess and I'm not an expert.
btw my first post, been lurking around for some time and hopt to learn more from this forum.
cheers.
Maybe through something similar to this? :
In the pic you can see the first plane has a scoop like thing on the DSI intake. If that scoop can be extended and retracted around the DSI bump you get a opening with varying cross section area.
Something similar may be possible for side intakes.
Just my guess and I'm not an expert.
btw my first post, been lurking around for some time and hopt to learn more from this forum.
cheers.
airsuperiority
Captain
Re: New Generation Fighter
Welcome to the forum (although I don't know why I'm the one saying this instead of the mods)
I hope you enjoy your stay. But just a coincidental note, someone with similar account name as yours(without the underscore), was banned not long ago. Not by any chance you're him right? Whether you are or not, have fun here, and avoid flamebaits or creating them. The mods here are quick to the job in detecting those and to track IPs
Welcome to the forum (although I don't know why I'm the one saying this instead of the mods)
I hope you enjoy your stay. But just a coincidental note, someone with similar account name as yours(without the underscore), was banned not long ago. Not by any chance you're him right? Whether you are or not, have fun here, and avoid flamebaits or creating them. The mods here are quick to the job in detecting those and to track IPs
Re: New Generation Fighter
This is NOT the same no_name as the noname who got banned! This no_name is a Taiwanese friend of mine from the Pakistan Defense Forum!
If anyone needs proof just go to Pakistan Defence Forum and check for his profile!
Welcome to the forum no_name!
This is NOT the same no_name as the noname who got banned! This no_name is a Taiwanese friend of mine from the Pakistan Defense Forum!
If anyone needs proof just go to Pakistan Defence Forum and check for his profile!
Welcome to the forum no_name!
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