JF-17 Thunder Multirole Fighter [Thread 7]

[python-000]

View attachment 439567

if you cant change the engine but Plz just change the nozzle of it

 

[Tempest II]

Dubai airshow video with no text across the screen:

 

[denel]

Hi neighbour!

http://www.funny.com/cgi-bin/WebObjects/Funny.woa/wa/funny?fn=CEW6R

ja man. u from zim's? Harare or bulawayo?

 

[Tempest II]

ja man. u from zim's? Harare or bulawayo?

Hre

 

[volatile]

Jee you guys it's not a big deal. It's not oil leak. Every jet engine upon shutdown "leaks" oil because most of the bearing used in turbines are sealed by air. When there is no airflow sealing the bearings on shut down, they "leak" in drip pan and out the engine. PAF mechanics are just lazy. It should be wiped clean after each flight on post-flight checks but they don't do it and now it's caked on the cowling

Hi is there an explanation for inflight and at during various RPMs the black smoke origination . The first part is a brilliant explanation but as an Engineer i do understand that Lack of Air/O2 or excess of Fuel can also be more reasons to have a black carbon or unburned fuel ,If my memory serves me correctly the DSI intakes were designed to minimized the smoke effect as PT-01

During that time Chinese were working on DSI for J20 program ,In my humble view RD93 being derivative of RD33 employs certain tools in manufacturing which are based on 60/70s technology and it is a crude but robust engine (having higher fuel consumption) also points out that its more then engine seals infact some how DSI /or intake has to be computer controlled at various profiles

 

[CriticalThought]

Hi is there an explanation for inflight and at during various RPMs the black smoke origination . The first part is a brilliant explanation but as an Engineer i do understand that Lack of Air/O2 or excess of Fuel can also be more reasons to have a black carbon or unburned fuel ,If my memory serves me correctly the DSI intakes were designed to minimized the smoke effect as PT-01

During that time Chinese were working on DSI for J20 program ,In my humble view RD93 being derivative of RD33 employs certain tools in manufacturing which are based on 60/70s technology and it is a crude but robust engine (having higher fuel consumption) also points out that its more then engine seals infact some how DSI /or intake has to be computer controlled at various profiles

DSI was created specifically to avoid the control surfaces for a variable intake.

 

[razgriz19]

Hi is there an explanation for inflight and at during various RPMs the black smoke origination . The first part is a brilliant explanation but as an Engineer i do understand that Lack of Air/O2 or excess of Fuel can also be more reasons to have a black carbon or unburned fuel ,If my memory serves me correctly the DSI intakes were designed to minimized the smoke effect as PT-01

During that time Chinese were working on DSI for J20 program ,In my humble view RD93 being derivative of RD33 employs certain tools in manufacturing which are based on 60/70s technology and it is a crude but robust engine (having higher fuel consumption) also points out that its more then engine seals infact some how DSI /or intake has to be computer controlled at various profiles

That's true. Since the engine was developed in 60s it employs old technology. Older civilian engines employed something called hydro-mechanical fuel system where the fuel controls the amount of air coming inside the core of the engine and how fast it's coming in. Fuel would first have to change the angle of guide vanes in order to allow ample or less air flow in the combustion chamber before it could be sprayed inside. Obviously the system being controlled mechanically is not the most efficient and there's always a second or two delay before the optimum fuel and air mixture is achieved and during that changes is when we would see black smoke which is basically unburn fuel.

 

[CriticalThought]

That's true. Since the engine was developed in 60s it employs old technology. Older civilian engines employed something called hydro-mechanical fuel system where the fuel controls the amount of air coming inside the core of the engine and how fast it's coming in. Fuel would first have to change the angle of guide vanes in order to allow ample or less air flow in the combustion chamber before it could be sprayed inside. Obviously the system being controlled mechanically is not the most efficient and there's always a second or two delay before the optimum fuel and air mixture is achieved and during that changes is when we would see black smoke which is basically unburn fuel.

Whilst it might be true for other aircraft, this is certainly NOT how Thunder operates. The Thunder's intakes have been very carefully designed to minimize heat signatures. @messiach

 

[razgriz19]

Whilst it might be true for other aircraft, this is certainly NOT how Thunder operates. The Thunder's intakes have been very carefully designed to minimize heat signatures. @messiach

Intake isn't the only thing that decides the airflow for the engine just FYI. There are hydraulically controlled surfaces that move to control the air flow in the core in response to throttle inputs.
Ever heard of compressor stalls?

 

[CriticalThought]

Intake isn't the only thing that decides the airflow for the engine just FYI. There are hydraulically controlled surface that move to control the air in response to throttle changes

DSI invalidates the need for said control surfaces. Air intake in Thinder is controlled through geometry. That's my understanding at least. @messiach

 

[razgriz19]

DSI invalidates the need for said control surfaces. Air intake in Thinder is controlled through geometry. That's my understanding at least. @messiach

Well you need to increase your understanding.
GE90 - one of the most advance engine in the world uses them.

 

[CriticalThought]

Well you need to increase your understanding.
GE90 - one of the most advance engine in the world uses them.

Yes, I know variable inlets are used by many modern platforms, thus increasing the weight. The Thunder inlets are simple by design to keep the weight at a minimum and DSI plays a key role in it. I hope that helps you in increasing your knowledge.

 

[khanasifm]

Hi is there an explanation for inflight and at during various RPMs the black smoke origination . The first part is a brilliant explanation but as an Engineer i do understand that Lack of Air/O2 or excess of Fuel can also be more reasons to have a black carbon or unburned fuel ,If my memory serves me correctly the DSI intakes were designed to minimized the smoke effect as PT-01

During that time Chinese were working on DSI for J20 program ,In my humble view RD93 being derivative of RD33 employs certain tools in manufacturing which are based on 60/70s technology and it is a crude but robust engine (having higher fuel consumption) also points out that its more then engine seals infact some how DSI /or intake has to be computer controlled at various profiles

Oem states developed in 85 ?? May be development was completed in 85

http://www.klimov.ru/en/production/aircraft/RD-33-family/

 

[razgriz19]

Yes, I know variable inlets are used by many modern platforms, thus increasing the weight. The Thunder inlets are simple by design to keep the weight at a minimum and DSI plays a key role in it. I hope that helps you in increasing your knowledge.

I don't think you understand how a turbine engine works. DSI only makes sure that air is available to engine in all phases of flight. It has nothing to do with how engine operates. You need to read before making such claims.

 

[krash]

Not sure what Musharraf's appointments have to do with an officer put in a marketing job who cannot speak well? If the man is not the right one for the job then its a problem. Be that in Musharraf's time or now at PAC.

Nothing. Had everything to do with the highlighted part in the quote, though.

"This officer would be perfectly fine in an administrative role within Pakistan."