IHPTET Brochure.

sferrin

sferrin

ACCESS: USAP
Senior Member
Joined
3 June 2011
Messages
17,332
Reaction score
9,067

Attachments

  • ihptet_brochure.pdf
    6.2 MB · Views: 71
Last edited by a moderator:
The link is unfortunately dead, does anyone have a copy of the pdf or knows a working link to download it?
 
Nice! Shouldn’t this thread be in the Propulsion category?
 
From the F414 section of the IHPTET brochure. A 2-stage fan producing 10% higher pressure than a 3 stage fan?

1709141755787.png

Or do they mean 10% increase relatively and not absolutely?
 
That is a 10% higher pressure ratio with a 2 stage fan vs the production F414 3 stage fan. So if the original F414 fan could produce a 4:1 pressure ratio, the IPTET fan could do a 4.4:1 ratio.

Since the IPTET fan has wider chord blades and vane, the two stage fan will be longer front to back than the first 2 stages of the production fan, although it might be shorter than all 3 stages. The wider chord airfoils can accomplish more work (I.e. pressure rise) than the narrower airfoils, and the exotic CFD shaping of the airfoils can be made structurally sound with the wider airfoils.
 
F119Doctor said:
That is a 10% higher pressure ratio with a 2 stage fan vs the production F414 3 stage fan. So if the original F414 fan could produce a 4:1 pressure ratio, the IPTET fan could do a 4.4:1 ratio.

Since the IPTET fan has wider chord blades and vane, the two stage fan will be longer front to back than the first 2 stages of the production fan, although it might be shorter than all 3 stages. The wider chord airfoils can accomplish more work (I.e. pressure rise) than the narrower airfoils, and the exotic CFD shaping of the airfoils can be made structurally sound with the wider airfoils.
Click to expand...
I've found no official number of the F414 fan PR but the F404-GE-402 has 4.3 up from 3.9 of the -400 variant. I think the F414 should've the same PR and should thus reach a PR of 4.7 with just 2 stages? That is very impressive.
 
Somewhere I saw a figure of 4.0 for the F414, which is why I used it in the example. Remember that the F414 has a larger (higher airflow) fan than the F404, which is responsible for a good portion of its thrust increase over the F404-400 and the -402.

Getting 4.4:1 FPR out of a 2 stage fan is outstanding, and if they can get 4.7 it would be pretty amazing. There are still real life considerations of stall margin under high inlet distortion, fan efficiency, and rotor speed margin at high inlet temperatures that have to be balanced against FPR, but fan and compressor performance have advanced significantly over the past 40 years.
 
F119Doctor said:
Somewhere I saw a figure of 4.0 for the F414, which is why I used it in the example. Remember that the F414 has a larger (higher airflow) fan than the F404, which is responsible for a good portion of its thrust increase over the F404-400 and the -402.

Getting 4.4:1 FPR out of a 2 stage fan is outstanding, and if they can get 4.7 it would be pretty amazing. There are still real life considerations of stall margin under high inlet distortion, fan efficiency, and rotor speed margin at high inlet temperatures that have to be balanced against FPR, but fan and compressor performance have advanced significantly over the past 40 years.
Click to expand...
When I went through A&P school in the late 1990s, the rule of thumb was ~1.2 PR per stage of axial flow compressor, though that may be just rotor stages, not including the stators. Getting something above 2.1 PR per stage is unreal to me!

If that rule of thumb was just the rotor stages and not the stators, they're still getting about 1.45 PR per rotor, another 1.45 per stator.
 

Similar threads

Back
Top Bottom