J-21/J-31 Chinese 5th Generation Stealth Fighter

THESIS THORON

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Many first world countries together set up that space station. China has one on its own while still a Third World nation.

And after 25 years, there are still just two :)
So what??

since they came together to setup the space station it is far more bigger than yours. That can't change the fact you have still not achived full operationality in your space station.
 

rockdog

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and what benefit get the uighurs from that if Xi ordered kill them?


I guess great science with barbaric policies China makes space station but Xi commits genocide
I think this is off topic stuff, then i make off topic reply to you:

Western knows genocide better than any other, then they would only use what they have done to explain others.


You as a Mexican, i wanted send my sympathy to you, but suddenly i realized you label urself as Westerner...

I respect your personal choice. But in generally, if somebody's ancestor is raped by someone, but this guy still call someone as spiritual father, i can only descirbe such kind of mentality as Bi**hness.
 

MiG-29SMT

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I think this is off topic stuff, then i make off topic reply to you:

Western knows genocide better than any other, then they would only use what they have done to explain others.


You as a Mexican, i wanted send my sympathy to you, but suddenly i realized you label urself as Westerner...

I respect your personal choice. But in generally, if somebody's ancestor is raped by someone, but this guy still call someone as spiritual father, i can only descirbe such kind of mentality as Bi**hness.
stop you false racial attacks, you can not accept that monster is killing people and using J-20s and J-31s to threat people, you live in the west, if you do not like it go back to the heaven is China, you will not because you know the monster is a dictator that kills UIGHURs


And by the way I am not racist, I have no problem with Japanese or Taiwanese or even Chinese people just with an evil political system that is arming to the teeth and oppresses people


Australian view
 
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rockdog

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Now consider RD-93 is 1 meter of diameter it has two so it has around 2 meters only of engine, add the bulkheads and boxy cross section, then you understand why J-20 is the prime fighter, it carries more fuel, the F-35 even having the same cross section area will have more area for fuel

View attachment 122799
The F15A used poor twin engines, but the F15E/F used upgarded ones, and F15E/F is still the best fighter in the world. Which proves that the plane is an outcome of balancing all the factors, including enigne, electronics, materials, aerodynamics. It's obsurd to judge the plane only by engines.

Plus, except F35, all the past US naval's fighters are two enignes.



basically you can not make an efficient V/STOL from J-31 aircraft because the engines are far aft and there is no space for a fan or lift engines
View attachment 122801

So china needs bigger carriers and obviously big ships, F-35B will be able to fly from smaller ships.

Consider it has no space for a lift fan because of its internal weapons bays do not allow it, basically J-31 is not well thought for a V/STOL it can not become one, for a reason the F-35 has side internal weapons bays and the engine closer to the center of gravity, the nozzle jet pipe is far forward for V/STOL reasons
The PLAN didn't ask J31 to be capable of the "V" from V/STOL. The combat envrionment nearby China dosen't asked for it, currently the F35B is no sense to PLAN.


Plus, i have to repeat again, do not use your hobby to challenge professionals. DFI is good place for exchanging info, but not the right place for really going to the technical details.

You would show off your out dated knowlegde in the title of engineer, but as a former computer sicence developer, i never show off analysis on how F22/J20 fly-by-wire system.

Sometimes, i guess if i throw you a DJI Phontom4 SDK, can you make any reasonable change based on such mature civil drone platform. If not, will be laugable to talk about how stealth plane works...
 
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rockdog

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stop you false racial attacks, you can not accept that monster is killing people and using J-20s and J-31s to threat people, you live in the west, if you do not like it go back to the heaven is China, you will not because you know the monster is a dictator that kills UIGHURs
No interest talking about politics in this thread, i think you should feel sorry to bring off topic stuff here.

But if you keep on doing so, i will keep on researching people has "Stockholm syndrome" like you .
 

MiG-29SMT

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The F15A used poor twin engines, but the F15E/F used upgarded ones, and F15E/F is still the best fighter in the world. Which proves that the plane is an outcome of balancing all the factors, including enigne, electronics, materials, aerodynamics. It's obsurd to judge the plane only by engines.

Plus, except F35, all the past US naval's fighters are two enignes.





The PLAN didn't ask J31 to be capable of the "V" from V/STOL. The combat envrionment nearby China dosen't asked for it, currently the F35B is no sense to PLAN.


Plus, i have to repeat again, do you use your hobby to challenge professionals. DFI is good place for exchang info, but not the right place for really going to the technical details.

You would show off your out of date knowlegde in the tilte of engineer, but as a former computer sicence developer, i never show off how F22/J20 fly-by-wire system.

Sometimes, i guess if i throw you a DJI Phontom4 SDK, can you make any reasonable change based on such mature civil drone platform. If not, will be laugable to talk about how stealth plane works...
Relax take it easy I have a Master in environmental Technologies , I am an engineer too, so take it easy, I gave you papers not by me but by aerospace engineers, you are in denial, The F-35 was designed to be basically a V/STOL aircraft, so the other versions are affected by that.

You do not want to admit the mass air flow is related to the size of the engine, the thrust is related to the mass flow and temperature the gases exit, to make an engine better than EJ-200 is not easy for that reason the Americans and Russians use the engines of higher size and lower RPMs.

That is a fact
 

MiG-29SMT

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No interest talking about politics in this thread, i think you should feel sorry to bring off topic stuff here.

But if you keep on doing so, i will keep on researching people has "Stockholm syndrome" like you .
relax false racist you are pretending to be white but the fact is you are as Mongolic as the native Americans and you pretend to discriminate a Mestizo with European ancestry , I do not want to be racist and I will not be, but first see you are not white and I am partially white, so stop your false racism. And by the way I am not the result of a Rape, my parents married, same my grand parents, so pretty much you are wrong
 

rockdog

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You do not want to admit the mass air flow is related to the size of the engine, the thrust is related to the mass flow and temperature the gases exit, to make an engine better than EJ-200 is not easy for that reason the Americans and Russians use the engines of higher size and lower RPMs.

That is a fact
I didn't deny the engine is the bottle neck of current J31 version, but it didn't mean there is no other option to improve the plane.

This is the real professional military watchers on latest version of J31, they don't only talk about engines.

China’s New Carrier-Capable Stealth Fighter’s Canopy Is Its Most Intriguing Feature

 

MiG-29SMT

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The F15A used poor twin engines, but the F15E/F used upgarded ones, and F15E/F is still the best fighter in the world. Which proves that the plane is an outcome of balancing all the factors, including enigne, electronics, materials, aerodynamics. It's obsurd to judge the plane only by engines.

Plus, except F35, all the past US naval's fighters are two enignes.





The PLAN didn't ask J31 to be capable of the "V" from V/STOL. The combat envrionment nearby China dosen't asked for it, currently the F35B is no sense to PLAN.


Plus, i have to repeat again, do not use your hobby to challenge professionals. DFI is good place for exchanging info, but not the right place for really going to the technical details.

You would show off your out dated knowlegde in the title of engineer, but as a former computer sicence developer, i never show off analysis on how F22/J20 fly-by-wire system.

Sometimes, i guess if i throw you a DJI Phontom4 SDK, can you make any reasonable change based on such mature civil drone platform. If not, will be laugable to talk about how stealth plane works...
ENGINE FEATURE M88-2 demonstrator • A/B thrust (lb) 17,000 20,250 • Dry engine thrust (lb) 11,250 13,500 • A/B specific fuel consumption (kg/daN.h) 1.70 1,70 • Dry engine thrust specific fuel consumption (kg/daN.h) 0.80 0.80 • Air flow rate (kg/s) 65 72 • Turbine Inlet Temperature (K) 1,850 1,850 (2,871°F) (2,871°F) • Pressure ratio 24.50 27 • Bypass ratio 0.30 0.30 • Length (in) 139 142 • Inlet diameter (in) 27.50 31 • Weight (lb) 1,977.50 2,171.50

you can not see M88 is a very small engine.

the air mass flow capture by the engine fan, is related obviously to the size of the blades, lower size lower air mass flow to increase thrust you can add higher temperature at the exit nozzle for that you need higher temperature and better metallurgy.

Since Rafale is not a big aircraft it is light but has no internal weapons bays, so it is lighter than J-35.

Now understand is easier to make a more powerful engine by increasing the size see

A newly upgraded Russian Tu-160 bomber made its first flight with the new version of the NK-32, the largest and most powerful engine ever fitted on a military aircraft

it is more powrful NK-32 but it is bigger
 
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rockdog

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relax false racist you are pretending to be white but the fact is you are as Mongolic as the native Americans and you pretend to discriminate a Mestizo with European ancestry , I do not want to be racist and I will not be, but first see you are not white and I am partially white, so stop your false racism. And by the way I am not the result of a Rape, my parents married, same my grand parents, so pretty much you are wrong

Curious question, just ask, no racism purpose:

As Mexican do you have local Indian blood? If so, do you feel good lable your self as western world?

If not, as Mexican you only have Spanish blood, how do you feel your ancestor killed 90% local Indians? As labled Westerners, do you feel guilty?
 

MiG-29SMT

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I didn't deny the engine is the bottle neck of current J31 version, but it didn't mean there is no other option to improve the plane.

This is the real professional military watchers on latest version of J31, they don't only talk about engines.

China’s New Carrier-Capable Stealth Fighter’s Canopy Is Its Most Intriguing Feature

let us do this, let us stop personal attacks, you are a human and same me we both have dignity and we should respect each other, like i said If you want to discuss Latin america i made a thread let us focus here in the aircraft in question.


this in NK-32 it is the most powerful engine now compare to m88
1638594577034.png


1638594656873.png


Size give you air mass flow, bigger engine more thrust with less fuel, problem for fighters bigger engine bigger cross section heavier fuselage and more drag, so f135 has excellent metallurgic technology

1638594715817.png


that is obvious in airliner engines.
 
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MiG-29SMT

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Curious question, just ask, no racism purpose:

As Mexican do you have local Indian blood? If so, do you feel good lable your self as western world?

If not, as Mexican you only have Spanish blood, how do you feel your ancestor killed 90% local Indians? As labled Westerners, do you feel guilty?
drop it, you do not know history concentrate here in j-31 if you want answer i already made a thread and i can prove you you are wrong there.
 

rockdog

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drop it, you do not know history concentrate here in j-31 if you want answer i already made a thread and i can prove you you are wrong there.
Who started off topic stuff? Do you feel sorry to bring it in?
 

MiG-29SMT

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Who started off topic stuff? Do you feel sorry to bring it in?
let us drop personal attacks, politics are true, but we should not insult each other you are a human as I am and we should respect ourselves focus on the question how can you make a supercruising J-31 which is harder than making a supercruising J-20
 

rockdog

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let us drop personal attacks, politics are true, but we should not insult each other you are a human as I am and we should respect ourselves focus on the question how can you make a supercruising J-31 which is harder than making a supercruising J-20
Alright, nobody asked you to talk about politics.

I take it as you said "Sorry".
 

MiG-29SMT

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Alright, nobody asked you to talk about politics.

I take it as you said "Sorry".
you do not need to apologize, we are humans and sometimes we forget our humanity, my point was it is harder to make an engine for J-31 than for J-20 for super cruise.

I mean Rafale can super cruise but it is a very light machine its fuselage has no internal weapons bays so it is light, J-31 has internal weapons bays, so it has a relatively longer fuselage than F-35, I doubt it has lower weight than F-35, at least it weighs 13400 kg empty weight, the MiG-29 is 11000 kg empty weight and it usually flew at a max weight of 18000kg, but every one knows the MiG-29 was not a long range fighter, it had a small range, pretty agile at combat but it has no range, consider both China and India chose Su-30 and in the Indian air force it is much more numerous, thus for a naval aircraft J-31 has no range, the new canopy is just to increase fuel and perhaps avionics.

The original J-31 was designed with a very aerodynamic good visibility canopy.

The main advantage of J-31 is stealth, relatively lower weight than Su-33/J-15.

To make an agile aircraft with RD-33 you need something like JF-17 but still it is a bit handicapped in TWR.

On F-35B that canopy is to house the fan but the F-35 has lateral internal weapons bays

1638608447745.png

on J-35 the landing gear is so close to the internal weapons bays to simply disregard any possibility it has V/STOL configuration


1638608541477.png

1638608720139.png


Now consider it is heavier than J-31, so J-35 will have lower TWR than J-31
 
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MiG-29SMT

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Alright, nobody asked you to talk about politics.

I take it as you said "Sorry".
now consider the importance of air mass flow rate

Abstract. This study presents an investigation on the effect of operational altitudes on the performance of the deteriorated engine. A two-spool high bypass ratio turbofan engine is used as the test subject for this study. The engine is modelled in Gas Turbine Simulation Program (GSP) based on an existing engine model from literature. Real flight data were used for the validation. Deterioration rate of 0.1% per day is applied for all turbofan components engine. The simulation is performed by varying the altitude from sea level until 9000m. Results obtained show reduction in air mass flow rate and engine thrust as altitude increases. The reduction in air mass flow rate is due to the lower air density at higher altitude hence reduces amount of engine thrust. At 1000m to 4000m, thrust specific fuel consumption (TSFC) of the engine is improved compared to sea level. However depleted in TSFC is shown when the aircraft flies at altitude higher than 4000m. At this altitude, the effect of air density is dominant. As a result, the engine is required to burn more fuel to provide a higher thrust to sustain the aircraft speed. More fuel is consumed hence depletion in TSFC is obtained.

https://iopscience.iop.org/article/10.1088/1757-899X/370/1/012001/pdf
Modern Turbofan engines can deliver high thrust without the high fuel consumption as compared to a turbojet engine. By trading the energy in the high velocity exhaust stream for power to drive a fan, the turbofan engine can process large amounts of air which yields a higher thrust per amount of fuel used. The amount of fuel used per thrust is called thrust specific fuel consumption (TSFC). A numerically lower value of TSFC is indicative that the engine uses less fuel to produce a given amount of thrust.


The larger the engine the more thrust is generated as well as the more fuel is consumed though at lower TSFC
.


To reduce the direct operating cost of environmentally compatible engines for small aircraft, a new concept of aerodynamic design technology “Zero Hub to Tip Ratio Fan ( ZH fan )” was developed, which is expected to increase the mass flow rate at the fan inlet without increasing the case diameter and to increase the fan’s inner total pressure ratio. Three dimensional aerodynamic design was conducted using Computational Fluid Dynamics, and each target for flow rate, efficiency, and pressure ratio was achieved in performance rig tests.

https://www.ihi.co.jp/en/technology...20/04/09/9416d01d0afcaaef11d9552c59375b0a.pdf


The last article expresses the main design goal of modern engines, but see the next article


Factors Affecting Thermal Efficiency of Gas Turbine Engines 21. Gas turbine engines are widely used as turboprop, turboshaft, turbojet and turbofan engines. The thermal efficiency will vary considerably, not only from engine to engine, but also with operating conditions. The thermal efficiency of these powerplants depends mainly upon: a. Compression ratio. b. Component efficiency. c. Air inlet temperature. d. The turbine entry temperature. The efficiency of the engine increases with increasing compression ratio (pressure ratio) so values in the order of 30:1 are now being produced. These high pressure ratios are more easily employed in larger engines, with the result that large gas turbines are usually more efficient than small ones. Thermal efficiencies of gas turbines are approximately in the range of 10% - 40% at normal operation


 
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SexyChineseLady

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relax false racist you are pretending to be white but the fact is you are as Mongolic as the native Americans and you pretend to discriminate a Mestizo with European ancestry , I do not want to be racist and I will not be, but first see you are not white and I am partially white, so stop your false racism. And by the way I am not the result of a Rape, my parents married, same my grand parents, so pretty much you are wrong
You are partially white and a racist to boot. You only "care" about Uighurs and brought this out of nowhere on a J-35 thread to attack China.

But you feel it is okay what happened to native Americans who were actually genocided by your people because they are mongolic like Chinese.

You are nothing but a white racist pretending to care about Uighurs but happy that whites had got away with killing off the native mongolic peoples of Mexico and the US.
 

MiG-29SMT

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You are partially white and a racist to boot. You only "care" about Uighurs and brought this out of nowhere on a J-35 thread to attack China.

But you feel it is okay what happened to native Americans who were actually genocided by your people because they are mongolic like Chinese.

You are nothing but a white racist pretending to care about Uighurs but happy that whites had got away with killing off the native mongolic peoples of Mexico and the US.
Modern Turbofan engines can deliver high thrust without the high fuel consumption as compared to a turbojet engine. By trading the energy in the high velocity exhaust stream for power to drive a fan, the turbofan engine can process large amounts of air which yields a higher thrust per amount of fuel used. The amount of fuel used per thrust is called thrust specific fuel consumption (TSFC). A numerically lower value of TSFC is indicative that the engine uses less fuel to produce a given amount of thrust.


The larger the engine the more thrust is generated as well as the more fuel is consumed though at lower TSFC
.



https://openscholarship.wustl.edu/cgi/viewcontent.cgi?article=1036&context=mems500

Factors Affecting Thermal Efficiency of Gas Turbine Engines 21. Gas turbine engines are widely used as turboprop, turboshaft, turbojet and turbofan engines. The thermal efficiency will vary considerably, not only from engine to engine, but also with operating conditions. The thermal efficiency of these powerplants depends mainly upon: a. Compression ratio. b. Component efficiency. c. Air inlet temperature. d. The turbine entry temperature. The efficiency of the engine increases with increasing compression ratio (pressure ratio) so values in the order of 30:1 are now being produced. These high pressure ratios are more easily employed in larger engines, with the result that large gas turbines are usually more efficient than small ones. Thermal efficiencies of gas turbines are approximately in the range of 10% - 40% at normal operation


https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/857224/Volume_03_Propulsion.pd
1638614038040.png

RD-93 of J-31

1638614066496.png


J-20 uses Al-31

which engine can generate more thrust? answer the bigger diameter engine
1638614139239.png


as basic i will put it simple it will be easier to make J-20 super cruise than J-31 why?

The larger the engine the more thrust is generated as well as the more fuel is consumed though at lower thrust specific fuel consumption TSFC.

A larger engine is more fuel efficient, your ranting is because you can not accept physics and you hide in distractors
 

SexyChineseLady

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Thank you for polluting this thread with meaningless technical mumble jumble and racial politics about bad Chinese "genociding" Uighurs and explanations that as a partially white person it is okay for Mongolic native Americans to be genocided in Mexico o_O
 

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