Bleed air

[dr_anthony]

Are the psi indicator decreases then air system modulates from 5th to 9th stage? 

Sorry, not at the PC now and couldn't check it myself.

[BjornMa]

Well, I would guess.

An easier way to explain it, is that; if the 5th stage can't deliver enough bleed air, then the 9th stage opens, to help.

[dr_anthony]

Yes, that correct.

FCOM 2.20.1:

"Engine bleed air is obtained from the 5th and 9th stages of the compressor section.
When 5th stage low pressure bleed air is insufficient for the bleed air system
requirements, the high stage valve modulates open to maintain adequate bleed air
pressure. During takeoff, climb, and most cruise conditions, low pressure bleed air
from the 5th stage is adequate and the high stage valve remains closed.".

PSI indicator in this time should decrease value, and increase it, then high stage valve modulates open. 

Is it in IXEG 737?

[Litjan]

Hi,

it is modeled - but right now it can not be seen because the 5th stage has been beefed up by us to provide more air during testing prior to release. It turned out that our model was not able to maintain cabin pressure running on only one engine at higher altitudes - before the 9th stage would open, the volume got too low. We could have tuned to make the 9th stage open at a higher PSI level - but this didn´t work according to the videos I made from the real plane, so as a stopgap measure we simple increased 5th stage pressure output.

We may tune this at a later stage.

In the real airplane you can sometimes feel it getting suddently warmer in the cabin during descents - the 9th stage opens, and the bleed air is considerably warmer than from the 5th stage. So before the AC system gets a chance to react, it first gets noticeably warmer...

Jan

 

[dr_anthony]

Fantastic! Great work at all. 

[dr_anthony]

Wish you guys to continue to create, and not allow the commercial side to spoil the whole thing