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

[Raymond G]

Dave wrote:

Some time ago I was able to get my hands on a copy of a study done at Iowa University, Aerospace and Engineering: "Analytical and Experimental Study of the Performance Characteristics of the Gluahar-eff G8-2-130R Engine" by Rory Eisele and Jesse Hilton. The study was performed in 2001 and ,among other things, includes thrust and acoustical tests. The abstract is one page, but the entire report is almost 40. Incidentally their engine was reported to produce a maximum of 110lb of thrust and turned into a blow torch with no thrust at nozzle pressures of 150psi or above. Presumably this was because of excess fuel flow flooding the heat exchanger. For those interested I should be able to scan it and post / email as desired.

Dave,
I would definitely be interested in that!

Raymond

[Viv]

Viv,

Unfortunately, it doesn't really matter what the supply pressure is if you are using a sonic nozzle; the gas will be accelerated to the speed of sound, and any excess pressure energy will just result in an increased plume density (and mass flow). So a supply of 700 psi and 1200F will still only give 1400 f/sec theoretical exhaust velocity from a sonic nozzle.

Raymond

Doh! if you think about it I knew this becouse it was what I was worried about happening in the first place:-(

I may need to go and have a little sit down and pick up all the threads again:-)

Viv

[Viv]

Luv, Viv,
I am concerned that there has been no verification to my inquiry about whether the supply propane is liquid or gas. I did see Viv's reply about 225 psi being above the propane's vapor pressure, but that is not exactly relevant. In any propane tank that is not COMPLETELY FULL, there will exist saturated vapor propane in the top portion of the tank. If the supply lines from the tank exit the top of the tank, then you will get saturated vapor propane (i.e. propane gas). If the line exits the bottom of the tank, you will get liquid.

Also, your plumbing may limit the available flow rate ( i.e. have flow restrictors, too long a line, too many elbows, high drag valves, adverse head, etc.) to below what the jet needs to develop full thrust. You really need to verify that you are getting the flow rate from your supply that the engine needs.

Regards,
Raymond

Fair comment but we will have to wait for Luc to confirm, can I also add that having had the weekend to think over what you were driving at it occured to me that if the supply line is restricted and the pump is near the jet end, the pressure drop on the pickup side of the pump may drop below the vapour pressure limit.

Viv

[Viv]

Guys

Three things:

Thing 1: Since we are talking about a device that is sonically tuned what are the side effects of trying to push a stream of fuel and possibly air through it faster than the speed of sound?

Thing 2: Some time ago I was able to get my hands on a copy of a study done at Iowa University, Aerospace and Engineering: "Analytical and Experimental Study of the Performance Characteristics of the Gluahar-eff G8-2-130R Engine" by Rory Eisele and Jesse Hilton. The study was performed in 2001 and ,among other things, includes thrust and acoustical tests. The abstract is one page, but the entire report is almost 40. Incidentally their engine was reported to produce a maximum of 110lb of thrust and turned into a blow torch with no thrust at nozzle pressures of 150psi or above. Presumably this was because of excess fuel flow flooding the heat exchanger. For those interested I should be able to scan it and post / email as desired.

3. Viv, if you are still looking for drawings / dimensions of the nozzle I can scan that portion of my plans for you. Just let me know.

Dave

Thing 1 Well as Raymond pointed out, with that nozzle you cant push any more fuel through it just chokes up and limits the flow.


Now air on the other hand may be differant! I have a worry about the designs capability to ingest air when static, on the end of a blade tip it gets ram air and the fuel pressure boosted.

Thing 2 That report sounds just what we need to cross check against, how quick can you get it scaned? is it availible on the net from them? Hell can I just get on a plane and pick it up later?:-)

Thing 3 Yes I would also love a scan of the nozzle, by the way we dont have a good scanned copy of the drawings for this engine on the forum? if you had time to scan them as well that would be appriciated by all of us.

Viv

[Viv]

The Gluey nozzle is a simple sonic nozzle with a .250 in diameter throat. A sonic nozzle means that it can only accelerate the gas to the LOCAL speed of sound (i.e. based on static temp at the exit). However there is a lot more pressure energy in the propane, and if a convergent-divergant nozzle is used, a much higher jet velocity will be achieved. I calc about 3000 ft/sec for the 225 psi, 1200F, gaseous propane available. Otherwise, as stated above, I calc only 1400 ft/sec. I never understood why Gluey used a sonic nozzle in his design as he surly must have been aware of convergent-divergent nozzles. In fact, most jet pumps (usually steam based) use just that. I always assumed that he knew from testing that his induction system worked better by allowing the sonic jet form the nozzle to free expand in the first stage induction tube.

Viv,
I calc 1400 fps for the sonic velocity of propane at 1200 F. I'm not sure how you got 2381 fps, but maybe you forgot the G term (32.17 in english system), or used stagnation temp instead of static temp?

Regards,
Raymond

I think he used the sonic nozzle for safety when the engine was blade tip mounted.

Think about it this way, the higher the pressure in the supply line the higher the thrust but when this baby is spun up the fuel line is pressureised by the spin! so we have a classic positive feedback loop!

The faster it goes the faster it gets:-)

The blades would spin up out of control as soon as you lit the engines if you had supersonic Delavel nozzles but with the sonic nozzles it has a built in limiter.

I would also assume he made sure the ram air would help to choke it down a bit as well by making the mixture lean off at high speed.

This engine was designed for a specific application to use it for a differant application I think it needs redesigning to get the best out of it.

Comments?

I really want to read that other report from Dave:-)

Viv

[Dave]

Guys

Good points on the speed of fuel delivery and good questions on air input.

I should be able to scan both the the Iowa State report and the nozzle today. Unfortunately, I can only scan portions of the plans as they are life size blueprints (EG: 3x4 or 5 feet) and our scanner is not. It will be late evening EST before I can get back to the forum with an update.

Dave

[Viv]

Guys

Good points on the speed of fuel delivery and good questions on air input.

I should be able to scan both the the Iowa State report and the nozzle today. Unfortunately, I can only scan portions of the plans as they are life size blueprints (EG: 3x4 or 5 feet) and our scanner is not. It will be late evening EST before I can get back to the forum with an update.

Dave

Dave I cant wait to get a read of that report:-) as for scanning the plans if there is a print shop near you that could do it then email me your address and I will send you a check to cover the cost of getting it scanned and reduced properly

Viv

[Dave]

PS to prior post:

Viv, the Iowa State is not up on line. The only reference I could find was:

http://www.eng.iastate.edu/newsletter/fy01/rag0106.html

It took me a few weeks (part time) to track down someone who could make a photocopy and mail it to me.

Dave

[luc]

Greetings guys,

I am back. I have also read all your previous post. May I make a suggestion ... At this rate, before we solve this issue, if we keep on posting like this, this forum will get to be a mille long. Now, I can see that we make a very briant 4 man team to solve this. So ... My suggestion is that maybe we can have a intermediate communication system, like Messenger, to do the Bla Bla Bla and use this post only for solid fact ... Up to you guys. My Nick name is faads45@hotmail.com

Okey ....

Raymond ... The pressure is measured at the control valve and at the nozzle. Both reading are identical. Dont forget one thing, in an hydraulic system, if the flow get bigger compared to what the pump can suply, the pressure will drop. Also, Gluey engine have restrictor of .080" in. wich is your true and only flow limiter. Also, the pump are supllied from a 1-1/2" line connected under a 500 gal. tank. Pressure is 225 psi. of liquid propane at evaporator and 225 psi. of gaz propane at nozzle.

Dave ... I definitaly want that Iowa report ... 110 ponds, Oufff... I want that.

Viv ... I have all the dawing you need ... Bud. They are in Acad R12 and R14 format. I have them on a CD. On that CD, I also have the manual. Got that when I purchased my first engine.

Conclusion ... Now that we know that the actual nozzle is good at 700 psi. but not at 225 psi. We need to design one that will perform like the Gluey one at 700, but using 225 psi. only. As for the flow rate ... Easy, we will just have to enlarge the restrictor and "Bingo" ... We will have pressure we want, Speed and Flow. Okey ... Now we need a sketch, a shape to start with. Then, I will run the shape on the CFD program.

Come on guys, get to your drawing board and give me a shape to start with.

Cya later

Luc

[Mike Everman]

Now, I can see that we make a very briant 4 man team to solve this. So ... My suggestion is that maybe we can have a intermediate communication system, like Messenger, to do the Bla Bla Bla and use this post only for solid fact ... Up to you guys. My Nick name is faads45@hotmail.com

Luc, I am not participating, but I implore you that the process you guys are going through must be preserved, blind alleys and all. Please don't take it off-line! Something in the Bla Bla is going to be valuable on a tangent to what you are trying to solve. Don't worry about the length of the thread...

My only contribution is that if you are considering the fuel pressure increase due to centripetal acceleration, of course you need to consider the increase in fresh air ingestion at the stacks from the same effect. The discussions so far with regard to the 700psi seem to assume that the nozzle is sitting in ambient conditions, when the nozzle's presence in stage one surely must be considered to be injecting into a moving reference frame, a stream that is already substantially in motion.

If Gluhareff was running this as blade drive, he certainly would have had a skirt or shroud around the intake stacks to protect the stacks from sidewise flow. If so, then the shape of the shroud and it's end conditions will in large part determine the ambient conditions at the nozzle.

On the rediculous side, perhaps we should consider some of the concepts encompassed by Special Relativity, substituting M for c!

[luc]

Mike,

By all mean, I don't want to short circuit the forum procees and what it can acheive. I just see that forum go longer and longer and I was concerned about the lengt of it and the forum host... That all.

Cya around and don't worry ...

Luc

[luc]

Mike,

By all mean, I don't want to short circuit the forum procees and what it can acheive. I just see that forum go longer and longer and I was concerned about the lengt of it and the forum host... That all.

Cya around and don't worry ...

Luc

[Viv]

Greetings guys,

I am back. I have also read all your previous post. May I make a suggestion ... At this rate, before we solve this issue, if we keep on posting like this, this forum will get to be a mille long. Now, I can see that we make a very briant 4 man team to solve this. So ... My suggestion is that maybe we can have a intermediate communication system, like Messenger, to do the Bla Bla Bla and use this post only for solid fact ... Up to you guys. My Nick name is faads45@hotmail.com

Okey ....

Raymond ... The pressure is measured at the control valve and at the nozzle. Both reading are identical. Dont forget one thing, in an hydraulic system, if the flow get bigger compared to what the pump can suply, the pressure will drop. Also, Gluey engine have restrictor of .080" in. wich is your true and only flow limiter. Also, the pump are supllied from a 1-1/2" line connected under a 500 gal. tank. Pressure is 225 psi. of liquid propane at evaporator and 225 psi. of gaz propane at nozzle.

Dave ... I definitaly want that Iowa report ... 110 ponds, Oufff... I want that.

Viv ... I have all the dawing you need ... Bud. They are in Acad R12 and R14 format. I have them on a CD. On that CD, I also have the manual. Got that when I purchased my first engine.

Conclusion ... Now that we know that the actual nozzle is good at 700 psi. but not at 225 psi. We need to design one that will perform like the Gluey one at 700, but using 225 psi. only. As for the flow rate ... Easy, we will just have to enlarge the restrictor and "Bingo" ... We will have pressure we want, Speed and Flow. Okey ... Now we need a sketch, a shape to start with. Then, I will run the shape on the CFD program.

Come on guys, get to your drawing board and give me a shape to start with.

I have access to a full version of autocad plus the volovuiew reader so if you could just email the files to me that wouyld be fine.

Cya later

Luc

MSN for brainstorming but I take Mikes point about keeping an archive of how the ideas are developing.

As long as its liquid propane at the ristrictor thats fine, I think the restrictor is another left over from the heliocpter blade safety limiter, but it also allows for a bit shorter heat exchanger.

Yep we need that report!

As to using another sonic nozzle, I would prefure to use the spersonic plug nozzle type from that nasa PDF, aerorocket do a design program for £20 so it could be done and it would not be wasting energy then.

The sonic nozzle is not efficient for a static engine I think, it would also lower the pumping requirments if you use a convergent divergent nozzle such as the Delavel or the plug type.

Viv

[luc]

Okey ... Update,

Before doing a CFD simulation of the nozzle at 700 psi. I think it would be important to do one with the Coils inlet at 700 psi. using liquid propane at ambiant temperature, to see what is coming of them in terms of temperature, pressure, flow and speed.

For some reasons, my CFD program is unable to mesh the coils as they are ... Coiled. So, I will make them straight, as 2 lenght of 11'6" long pipe and try to do the test using a wall condition at 3600°F. Will see what is coming out, hopefully, if my damn CFD program will mesh those.

Afterwhat, I will run a CFD simulation of the nozzle under the condition resulting from the test above.

Meanwhile, I hope we will get our hand on that Iowa abstract and that someone will have come with a preliminary New Nozzle shape.

Standby for results ... He he he.

Luc .....Out

[Raymond G]

Luc Wrote

Conclusion ... Now that we know that the actual nozzle is good at 700 psi. but not at 225 psi. We need to design one that will perform like the Gluey one at 700, but using 225 psi. only. As for the flow rate ... Easy, we will just have to enlarge the restrictor and "Bingo" ... We will have pressure we want, Speed and Flow. Okey ... Now we need a sketch, a shape to start with. Then, I will run the shape on the CFD program.

Come on guys, get to your drawing board and give me a shape to start with.

Luc,
I'm not sure what it is that you are getting at here, so could you spell it out explicitely. Once, you do I will probably be able to design, draw, and download what you need in about 1/2 hour. Would ACAD 14 .dwg be OK?

Regards,
Raymond