11/127 manned flight engine.

[praendy2203]

Hi John,

much improvement👍

The egt is still heigh, but when you build a new combustion chamber you can try a different hole setting.

You say the color in the front did not change much, like before.

I know, you know what to do!

Perfect trust so far.

I recomment a second scale 100 lbs+

Then you will have 300 lbs in summary.

Thats the same, when you want to drill a 8 mm hole.
Then you can use a 4 mm drill bit and use it twice in the same hole😂

Andy

[racket]

Hi Andy

Yes much improved , temps are still high because of the delayed combustion , but thats not such a problem now .

Interestingly there was more needle bouncing from the P4t gauge than the P2 gauge, maybe the jetpipe combustion was causing that

LOL.....does 3 passes with the 4mm drill make a 12mm hole ;-)

I've got a 500kg load cell available , just need to workout how to get it hooked up to a computor , I'll be needing it once the A/B is fired up .

Cheers
John

[racket]

Hi Richard

Yep , those 900C temps are high , but I think they're more from jetpipe combustion as the wheel colour doesn't indicate the same level .

Flametube combustion is still displaced too far down it , the new flametube design with better hole placement and front wall thimbles should bring that much closer to the front wall as it did with the 12/118 engine .

Cheers
John

[racket]

Hi Andym

OOPS , missed your email :-(

I'll be here for a chat

Cheers
John

[racket]

Hi Guys

Front wall of the new flametube finally finished , making those 18 thimbles is a chore , ~30 minutes each one , 9 hours of boredom .





Now for some easy "tin work"

Cheers
John

[racket]

Hi Guys

The flametube is coming together , just the outer wall to go .





Cheers
John

[racket]

youtu.be/8vgLOobE0KM

[racket]

Hi Guys

Engine is just about reassembled .

New flametube and air deflector





I'm also attempting to measure static pressure exiting the NGV , just before entry into the turb wheel to see what the actual pressure drop is across the NGV , using 1/16" dia stainless tubing , thanks Richard

One of the exducer shroud retaining screws was drilled out and the tubing inserted through it , a few dobs of silicone glue to seal, and to hold lockwire in place .




The afterburner hot streak was repositioned to enter through one of the Secondary holes using a short length of the stainless tubing , I'll initially use it to measure static pressure within the flametube to use in the calcs for the NGV pressure drop .


Cheers
John

[racket]

Hi Guys

Engine is back on the test stand and in the car trailer

A few more gauges added




Time to make up a fuel brew and charge batteries

Cheers
John

[racket]

youtu.be/N01BXp4FFw0

www.youtube.com/watch?v=MskkJBACOiY

[pitciblackscotland]

Nice run there John. How do you think this run went? I notice one of the top right black face gauge was bouncing a bit on shut down.

Cheers,
Mark.

[racket]

Hi Mark

The run itself went OK , fired up without the need for propane preheat , but I must have "done something" to the TOT setup as the temp didn't vary , theres too many options on these electronic thermometers , all I want is the temperature at the thermocouple , I probably "adjusted??" the settings , I'll have a look at it today and get the blowtorch to the thermos to check them out .

That bouncy gauge measures the static pressure ~10 mm in front of the inducer tip , theres a 1.1mm hole drilled through the alloy that I have a syringe needle inserted into with some plastic tubing back to the "boost/vacuum" gauge , its only an old gauge I used on my turbo bike from the '80's and its needle doesn't read zero but its good enough to get an idea of whats happening , and that bouncing has me intrigued , I've watched it several times and the only conclusion I can come to is "surge??" or some weird shock waves off the tip .

Today I'll "calibrate" the other new gauges , the bigger one at the top measures pressure inside the flametube , its hooked up to the hot streak pipe , so I'll hook that gauge and the P2 gauge to a common supply to check if they are reading the same and theres no "correction" to be made .

The bottom right hand gauge is the NGV static outlet pressure , I'll check it against the P2 gauge as well as the flametube internal pressure.

Once I've got the numbers I can do some calcs .

My big disappointment was the fuel supply , I still can't get enough into the engine to get up to my 3 Bar P2 , 60 psi delivery pressure even with the two pumps isn't enough , ......work to be done to rectify this , I'll do some insitu flow tests first to get a datum to work from .

Otherwise I'm happy with the test even though no improvement in thrust , theres was only a mild glow at the turbine at full throttle , no visible flames , though the bright mid day sunshine wasn't good for filming .

I'll post more later once I get the numbers sorted :-)

Cheers
John

[pitciblackscotland]

Hi John, remember i have that gear pump i can send up to you if you want to test it out and have a IC leaf blower motor i think it works. That motor could be use to drive the pump

Cheers,
Mark.

[slittlewing]

Hi John,

After watching the vids I think the thermocouple reader might have been set to display “maximum”. So the temperature reached during engine start with presumably the normal flames out of the back (695deg) was then displayed on screen for most of the idling until that was exceeded at higher P2. So it looks like 715deg at 2bar p2. It’s hard to make out the temp at 2.5bar steady P2 but it looks like 880, then 975 during the quick throttle ups to 2.75bar?

Maybe one easy thing to try for the fuel pressure difficulties would be using an additional battery in series to give 24v supply for them, if you are using 12v at the moment? You could do a bench test with engine off and compare max fuel pressure with 12v vs 24v 🙂

Cheers

Scott

[racket]

Hi Mark

I did a series of insitu tests yesterday , with and without the lube pump operating, and theres more than enough pump output , only an ~3% drop with the lube pump on , I'll check other things today .

Thanks for the offer but the current setup should be more than adequate , nice pump though , good for some high pressure spraying :-)

Cheers
John