Gluhareff 130R power failure issue still open ... Any Idear?

[Dave]

Luc

I looked carefully at the picture of the expanding nose cone and believe that some measurements are in order. It might be that the nose cone is expanding, but it is also possible that the Combustion Chamber is shrinking. If I remember correctly, you told me that the combustion chamber is a 7 inch pipe stretched to 9 inches to form the CC. Stainless has a nasty habit of springing back to its original shape. Shrinkage of the combustion chamber may also help to account for the 0.55 inch difference in measurement from the lip of the 3rd stage to the other side of the CC. Please humor me, when you or Patrick have a few minutes, please measure both the nose cone and combustion chamber so we will know for sure.

Next, were any of these tests run with a telescopic 2nd stage? Based on your prior measurements and calculations, reducing the length of the 2nd stage may have a positive impact on thrust as this could help to line up the wave forms. The only nasty I can see here is that making the necessary changes in relationship between the 2nd and 3rd stage may also screw up the relationship between the 1st and 2nd. This is because the 2nd stage will have to move toward the 3rd to compensate for the reduction in length but the nozzle will remain in a fixed positon.

You are probably still waiting for delivery of the new 1/2 inch 321 tubing, so I will not ask about the coils yet.

Dave

PS: Did you get a good look at the spacers to center the 2nd stage inside the 3rd stage on the paper plans? They also show up in the pictures posted earlier by decook1110.

[Raymond G]

Luc,

Hooo...one more thing,

I guees you have figured that one out... But in case you need to know, there is alot of air coming out of the 3rd stage at max power.

During warm-up, the intake stack is capable of maintaining the flame front inside. But this thing spit like a dragon at max power.

One thing is sure ... The combustion is to strong, or the intake stack is to weak ...

You tell me...

Uhhhhmmmmmm.

What are we all supposed to say to that?!!?!?!?!? As Viv put it, it would have been nice to know this little tidbit ..........about 25 pages ago!!

So now we know that backpressure is too high in the third stage ejector. Either stages 1 and 2 are not delivering rated pressure (are not tuned to each other properly), or stage 3 and/or the combustor have too much resistence (not tuned to stage 2). We need to think how this relates to those pretty spectrum pix, but my brain is too tired right now.

Raymond

[Raymond G]

decook1110 wrote:

He also mentioned how Gene seemed to be having a hard time getting his 130R's working and that he had to do some mods to get these working. He didn't do a very scientific test on the engine, he only ran one engine at a time and used a bathroom scale against the planes nose to measure thrust.

Dave,
Thanks for the info and the great photos. Your above statement would imply that a third party thrust measurement was actaully taken on a G8-2-130R that Gluareff himself tuned. Is this correct, and if so, do you know the results? This would be a very important piece of data.

Regards,
Raymond

[decook1110]

I can't remember the guys name right now, but he is in the G8-2 tech manual. As I mentioned he wasn't very scientific, but he did mention checking thrust by pushing against a scale with the aiplanes nose. he had gone through a few iterations to get the engines to run properly. He implied that Uegene Gluhareff himself was having problems getting the 130r to work, it was apparently more finicky (technical term!!) than the others.

I personally believe the engine will give 130 pounds due to its size, I'm really curious to see the SFC. With the latest developement, I think you have hit a tuning issue. Maybe this design didn't scale well and was marginal and sensitive to tune. This could be a loss of nozzle energy. Kind of a simplistic approach, but as the Nozzle pressure keeps going up, the propane leaving the nozzle will start expanding more and more and may at some point not draw anymore air into the intake because it expands so much and isn't traveling into the 1st stage anymore. Its always limited to sonic velocity which is a function of temp, it will just expand more as its exit density increase at the same speed. Nozzle temp may be dropping as flow and pressure go up, which would also drop the energy available which translates to dynamic pressure at the entrance to the 3rd stage. I always wondered why there wasn't an effort to use a diverging nozzle to catch more of the momentum of the propane in the direction that helps bring in more air and develope more pressure. I haven't seen this myself, but I've been told that the exit angle on a nozzle can turn past ninety degrees if it is underexpanded enough. At 160 psi with a straight nozzle, the gas is very under expanded.

I've been following as much as I can, but I don't have time to go back and read all 25 pages. I noticed that you were talking about new coil material, so forgive me if this is covered. But is the coil material in the current engine the thickness specified? What would it take to add a new injector nozzle with the same throat, but with some divergence. This was something I was going to play with, but as I mentioned I lost interest real fast when I concluded that the SFC was so grossly exagerated.

Luc, great job. Its really interesting to see someone working with this and I wish I were doing it myself. I hope my babbling now and then is some help, I realize I'm only a spectator. Thanks... Thanks to all the Net helpers also ...

Oh, and at what nozzle pressure do you start seeing the back up in the 3rd stage?

Dave

[Raymond G]

I can't remember the guys name right now, but he is in the G8-2 tech manual. As I mentioned he wasn't very scientific, but he did mention checking thrust by pushing against a scale with the aiplanes nose. he had gone through a few iterations to get the engines to run properly. He implied that Uegene Gluhareff himself was having problems getting the 130r to work, it was apparently more finicky (technical term!!) than the others.

Even with this 'unscientific approach', did he ever mention measuring anything near rated thrust?

I personally believe the engine can give 130 pounds due to its size, I'm really curious to see the SFC

I agree. The engine is certainly large enough to generate 130 lbf, especially if it can generate ~50lbs with the 3rd stage spilling air!!! As for SFC, I have always secretly hoped that somehow the tuning resonences create a greater chamber pressure than is possible simply with the kinetic energy of the propane jet. If all chamber pressure comes only from propane jet kinetic energy, then I also calc SFC~3 lbm/lbf*hr. If the standing waves can somehow 'trap' a higher pressure wave in the chamber(perhaps by some kind of energy transfer between thermal, sonic and pressure), then a much lower SFC is possible. Also, as a point of interest, Zoltan claims a static SFC of .9 lbf/lbm*hr for his induction jet, and says it uses 'acoustic resonators'.
Of course another possible mechanism for low SFC, even in the Glueys, is effective 'bypass' thrust, like in a turbofan, were there is a core of relatively high pressure, high temp gas, and a bypass of lower pressure, lower temp air that it drives. How this mechanism would work in a Gluey I could not say. But I have calculated much lower SFC's for such a system, if it is possible. It is worth noting that the G8-2-130R's combustion chamber temp should be on the order of ~4000F if the air/fuel ratio is really stoichiometric (i.e. ~ 14.3:1), which does not feel right.

I always wondered why there wasn't an effort to use a diverging nozzle to catch more of the momentum of the propane in the direction that helps bring in more air and develope more pressure.

Me too. It may be that the ejector lengths would have to be very long to get such a system to tune, or it might be that the shock diamonds would generate too much 'noise' and prevent any sonic resonence from occuring. Or maybe he just didn't think of it :-) (I doubt).

I haven't seen this myself, but I've been told that the exit angle on a nozzle can turn past ninety degrees if it is underexpanded enough.

Actually, you probably have seen it. Recall the Apollo moon shots, and the long range movies of the Saturn V first stage just before burnout. You will see the exhaust plume actually climb up the sides of the rocket, as the F1 engines became grossly underexpanded at high altitude.
Sorry for the long post, but your messages have 'resonated' with me. ;o)

Regards,
Raymond

[Raymond G]

Dave wrote:

Maybe this design didn't scale well and was marginal and sensitive to tune.

I have thought about this and wonder if it is a boundary layer issue. With the smaller designs, boundary layer growth in the ejectors will change the effective length/diameter ratio more than in the larger ones. It may be that with smaller length/diameter ratios, tuning becomes more sensitive.

Okay that's it, I'm going to bed.

Raymond

[Viv]

Look at the two attached pictures, and try not to glase over when you realise that Viv is posting more bleeding spectrums:-)

Forget all the complex stuff and just count the lines and look at how high they are, now look at the ones marked second stage and first stage on both spectrums.

on the G8-2-20 the second stage inlet line is higher than the F2 line (second from the left) this is the inlet amplitude, its what pushes the fuel/air in to the combustion chamber against the combustion pressure.

Now look at Luc's engine! see the differance? the F2 line is loads higher than the second stage inlet line, so his inlet cant push the fuel/air in and in fact when he finally graced us with a bit of late information he admitted that the engine blows out the inlet at full power.

So what does it mean, we have a picture now of a working engine with the resonance of the components and what resonance mode they should be in, we also have a picture of a none working engine:-) so now we can compare.

for the engine to work at full power the combustion chamber and tail pipe must resonate as a closed end tube supporting f1 f3 f5 and so on, the odd multiples (1/4 wave mode).

the inlet resonates as an open ended set of tubes and supports the odd and even series f1 f2 f3 f4 f5 f6 f7 (1/2 wave mode).

The combustion chamber F2 frequency is not part of the inlets possible frequencys, the second stage has the lowest frquency at 576hz, the combustion chambers F2 frequency is 287hz.

Now looking at the way the harmonics multiply we can see that they are approximatly in the right places! so the tuning cant be that far out of wack.

But they are at the wrong amplitudes, at low power up to 50psi fuel pressure and 10lbs of thrust the engine is in 1/4 wave mode, the same as Eugenes engine in fact, the inlet is working ok and the second harmonic is lower than the second stage inlet, but as soon as the power goes up it swiches over.

Now the second harmonic has grown and overpowers the inlet resonances amplitude and it starts to spit back out of the third stage (finally confirmed by Luc).

So we have moved forward but not all the way, why is the second harmonic going up at high power?, what is resonating at 267hz? is it the engine going over to 1/2 wave mode (open tube)? or is it another part of the engine resonating and becoming dominant?

And the final question! Does luc have any more important clues he has forgotten to tell us?

Viv

[Dave]

Guys

When I was with Luc to record the engine he showed me some video of a night firing they did. The 3rd stage spillage was very clear in that video and I simply attributed it to the intake tuning problems we already knew existed. Unfortunately, I did not think to pass along that bit of information either, so I deserve some of the discredit as well.

So, now that the confessions are out of the way, maybe we can get Luc to post or email a clip of that night firing video. If I remember correctly it also has an audio track and the 3rd stage spillage was sporadically visible. Perhaps the combination of the video and synchronized audio track will provide us with more clues. If it will help, I may have some software that allows editing of the audio track on a video frame by frame basis. I have never used it for that purpose, but it might be worth a try.

Dave

[Viv]

Guys

When I was with Luc to record the engine he showed me some video of a night firing they did. The 3rd stage spillage was very clear in that video and I simply attributed it to the intake tuning problems we already knew existed. Unfortunately, I did not think to pass along that bit of information either, so I deserve some of the discredit as well.

So, now that the confessions are out of the way, maybe we can get Luc to post or email a clip of that night firing video. If I remember correctly it also has an audio track and the 3rd stage spillage was sporadically visible. Perhaps the combination of the video and synchronized audio track will provide us with more clues. If it will help, I may have some software that allows editing of the audio track on a video frame by frame basis.

Dave

Hey thats big of you Dave but its more fun to just dump all the blame on Luc:-)

The video sounds interesting i would like to see that:-)

Hows the snow in Buffalo

Viv

[Viv]

Ok I may be tempting fate but talking to Luc on MSN and we may have found out what the problem is!

But I wont say untill he has tested it out:-)

You will laugh if it true though;-0

Viv

[Dave]

Viv

You’re killing me! Now I’m going to be on the edge of my seat for the rest of the day waiting for the results of these mysterious tests!

I hope it does turn out to be something simple and easy to fix. Even if it is, I think we will all still feel a sense of accomplishment that we participated in the process. And if we get a good laugh out of it, well that’s just a bonus.

Dave

[luc]

Woww ... Took me a while reading al those posting. You guys FINALLY.. Woke-up? ... he he he.

Okey ... I will answer all this orderally ... So, Starting with :

Deccok1110]... Yes there is a post somewere in the previous pages, of the thrust vs nozzle pressure. And yes, it is linear. But remember, we are just starting to realize that most of the R. Q. Riley manual is 90% bullshit.

And of course the space ranger is a fake. I can't hardly stay next to my engine (Ask Dave) when this thing is yellow hot. How do you beleive this poor guys stood between 4 of them. Ask Patrick ... I saw him smoke a few times ... he he he.

As for Craig W. Welll ... Let say he is on another project and is under non discloser agreement with Irina Gluhareff. Even if Craig help me at one point ... Hummmm ... I think I am gonna stop here. Let say that something happen between me and Craig and I don't real like guys that think others (Refering to guys from this jet comunity) are idiots.

As for the plane you saw (Nice picture by the way) will probaly rust in his garage forever. I hate it when something get lost like that. For what it is worth, tell your friend that I would be glad to complete it and fly it. But he will probably let it site. That what I call ... Lost technologies ... For nothing.

Dave ... My budy Dave ...

The combustion chamber is of 9" tube. It is just the tail pipe that as been strech to form the Combustion chamber to tail pipe transition.

As for the .55" difference, it is a simple mechanical assembly mistake.

And yes ... we are still waiting for the coils. They should come in tomorow. I also have stage 1, 2 and thermocouple. The chamber 4000 °F has a 2 week delivery time.

Raymond ...

DON'T push it...Raymond ... He he he. Beleive me, Viv was more then I needed to this morning. He was waiting for me on Messenger, with a baseball bat. I just FORGOT ... I though that you guys already knew that. Ask Dave, I showed him the video like this was old news.... Okey ... Okey .... I AM SORRY... You guys happy now ... he he he.

Back to Decook1110 ...

Like Viv said ... We think we know why this engine is so Finiky ... He he he ... One more test ... and we will know ... He he he.

As for at what pressure do I loose the thrut ... My harmonic are screwed only at Max. Power (165 psig.)

As for devergent nozzle ... Look in the previous pages...It is there. We also did a CFD analysis. And it is so fast, it look like a laser beam gowing through that intake stack.... See the previous pages.

Okey ... Now, for all the guys. Know this, I have no secrets ... Just alot on my mind this time.

As for the night run video recording ... I tryed and tryed and tryed to post it, untill I got sick of it. I will send it tonight at my Budy Viv. And Kenneth ... I hope you make a damn good back-up of this forum.

And as for my good budy Viv ... All I can say, after you JUMPED on me so hard, like you said in your previous post .... He he he .... Your a bitch ... Lolll.

I will get you one day ... It will come to my turn ... ONE DAY ... he he he.

Hooo ... Viv. Bye the way, we are almost ready to test our new findings. If it is confirm and finally solve this engine. I FORBIDE YOU TO GIVE THEM THE ANSWER ... I want you to give them the same clues we had this morning, ask them that simple question (You know which one) and let them chew on it for a day ... he he he (I am so meannnn).

That would be called ... OJT ... for "On Job Training" ... he he he.

That's my revenge for you guys Jumping on me so hard ... Just for a little forgivness ... he he he.

Cross your fingers ... I am going out with the engine now ... For maybe, the final test.

Cya,

Qaplaaaa,

Luc

[luc]

Ouppssss ... forgot the camera.

To take picture of that ... LoadCell Meter ... If all goes well.

Did I say I was going out ... With the engine ... For maybe the FINAL test.

Yess.... I did ... Sorry,

Cya in 20 minutes .

Luc ................ Out

[Viv]

Well at the moment they are all outside the factory in the snow trying to do this test with the new modifications to see if what we think is true and it is a simple problem.

Poor patrick has had his arm up the back end of the engine like an artificial insemination vet for the last couples hours trying to do the mods with one hand and good imagination?

I hope it works as I have a very funny MSN conversation I will post if it is:-)

Viv

[Viv]

Ahhggggggg!

The tension is just starting to get to me, the modifications they just did were quick and dirty so we could test out wether we had isolated the problem.

So they set it all up out side ran the engine up and the quick and dirty mods melted and flew out the exhaust before it hit full power and we could find out any thing:-(

what a bitch!

So we all now are going to have to wait untill Friday when the new coils are done and fitted and we can try it again.

I don't think I can wait that long personaly:-)

Still you all get a few days to try and guess what the answer is:-)

I have posted all the clues you need so good luck:-)

Viv