HPST 2020 Jet Engine

[racket]

Hi Andy

Nice pics , just what we need :-)

Lotsa V gutters there, which helps explain your good combustion, nice touch with your expansion sliding mount .

Good diffuser downstream of the wheel .

A classy bit of work :-)

Cheers
John

[finiteparts]

Hi Andy,

Thanks for sharing your A/B design. Wonderfully simple design and it performs so well. I like the fact that you not only have injectors inline with the v-gutters, but also injectors between the v-gutters to better feed the entire afterburner flow. It is sort of surprising that those brass nozzles survive, but they do and that is a great way to get tight-toleranced fuel jets.

Are you seeing any buckling of the screech liner? Typically, in full size engines, the liner is corrugated to try to help add section modulus as a means to stiffen the liner. Also, your screech liner seems to be doing a great job damping out any acoustic resonant coupling with the heat release. The typical sudden expansion AB designs screech like a banshee and would be very challenging to incorporate a screech liner in.

Is the ignitor in that large nut that is inline with the v-gutters?

Thanks again for sharing.

Chris

[praendy2203]

Hi Chris,

one spot in the flametube from older tests is not "round" anymore.

In the beginning I only had those brass nozzles without the "heat shields".
Combustion was bad and I saw some glowing streaks in the outer tube.

Then it was clear, the injected fuel is not going in the center behind the turbine wheel and because of the centrifugal force of the gases the fuel sneaked somewhere outside.

These shields are also some nozzle extensions to get the fuel into the right spot.

The spark plug is removed, because the a/b ignites with a hot streak.
What you see, is just a screw and a nut to close the hole.

I was a lucky guy when i worked in an airline and they sold me some sheets of Inconel 625 for a few €.
The complete afterburner is made of Inconel.
Now guess, how to drill those 450 holes🤣🤣🤣

Tank you👍

Andy

[richardm]

Carbide drill and lots of patience? M ay be some elbow grease too?