Gluey Fuel Consump/pulse jet debate

[jim]

OK, the fuel consumption experimentally determined by Luc is about
right for the Gluey engine. The published rates for the 20-80 lb thrust
engines are 4.2-4.8 pounds of fuel per pound of thrust per hour. Only
the 130 engine has a different published rate of about 1. I suspect the 130 fuel consumption rate is wrong. For the former, for an engine
running at 75 lbs thrust for 5 minutes, the calculated consumption would be: 4.2x75x 5/60 = 26.25 lbs of fuel. This about what Luc got. Now, this is understood to be static thrust. Dynamic thrust could be significantly less
as air is pumped in through forward thrust. As in the Gluey patent,
the intake is enclosed with a scoop and facing forward to capture air. It would be expected that under dynamic conditions the fuel consumption would be less. Second point: In my opinon, the Gluey engine is a
pulse jet, as I so stated six months ago on this site. Why? Because of how it operates. A pulse jet is basically a tube that resonates and takes in air at both the intake and the exhaust. Some estimate about 90% of air is pulled in during the negative cycle. This means that any object placed near the exhaust or intake will interrupt the flow of air into the engine and disturb its operation. The design of the Gluey is obviously made to capture a maximum of air from the tail, because it has an open tail. The
trade off of an open tail is poor thrust, simply because it reduces combustion chamber pressure. A restriction of the tail to a reduced diameter would increase combustion pressure but reduce air intake. It's a no win situation for this type of engine. However, the inventor really has accomplished something (in my opinion) because he invented an engine with no moving parts, and was able to create an open valve. He got the fuel to the combustion chamber without it burning in the intake. This is
an accomplishment, and I know because I have built hundreds of propane engines and seen how difficult it was. Regarding the engine losing its resonance, I have seen this before, and it is not common with valveless pulse jets. It is a symptom that something is wrong with the design. Valveless pulse jets burning propane are very stable and start very easily. I'm done. Jim

[luc]

Hi Jim,

Thanks for the quote on the work I have done.

But also, I can't stop my self in going against your pulse jet theory. Don't worry bud, I am also in opposition with Viv on that one ... He he he.

You said :

Second point: In my opinon, the Gluey engine is a
pulse jet, as I so stated six months ago on this site. Why? Because of how it operates. A pulse jet is basically a tube that resonates and takes in air at both the intake and the exhaust

Okey ... I am gona kill that theory one and for all. Let me ask you all this question. It was proven and well establish that a 2 cycle Motocross engine, or any 2 cycle pistons engine, re-ingest some of their exhaust gas after the duty cycle ... Does this mean that this engine is a pulse jet too ... The answer is NOOOOO.

Pulse jets are pulse jets because they have a dead moment. A fraction of time were there is no momentum in the gas velocity. Like the lockwood is a valveless pulsjet because it also, has a dead momentum.

Now ... I am gonna totally destroy that theory. Is a ram jet going trough air and producing thrust, a pulse jet? .... The answer is also ... Noooo.

Now ... Why would it be different with the pressure jet? .... Well it is not and let me proove you why. If you would open the propane suply valve of a pressure jet, WITHOUT igniting it ... You would have a STEADY flow of propane/air mixture, flowing from the intake, trough the combustion chamber and out the exit. And just this alone, is enough to kill that "Presseurejet being a pulse jet" theory. A pressurejet running is exactly like a ramjet going trough air. The difference is the mean of feeding both engine. One has inlet pressure suplied by a bottle and the other by a flying plane.

A pressure jet might have a

Burning cycle

, like the ram jet does. But the only difference between does 2, is their repective burning cycle frequency. But there is no flow interuption in a pressure jet, there is non dead momentum also.

Furthermore, we are currently testing engine #4 and #5. I could also take a picture of both engine thrust oscilation patern that is observed on the osiloscope and I can tel you guys, that in no time the thrust of those engine nears the zero line when they are running. By tunning them, you can have a flater osilation (i.e : from 70 to 110 pnds) or bigger peaks (i.e : 50 to 130 pnds) ... But NEVER, you will see that slope hit the zero line. Therefore, prooving that a pressure jet never stop pushing. Even so minimal it can be, it always deliver something.

Don't mistaken

Burning Cycle

and

Pulsing Cycle

.

And I know Viv will go .... "Whattttttt..... Nowayyyyy ...." He he he.

Cya Jim and others,

Regards,

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

[Mike Everman]

Luc,
I disagree! There is no doubt that it is a pulsejet. Though, I think it's more precise to say that it is a pulsating ramjet. It is as simple as this: you are simulating forward velocity by using the kinetic energy in your fuel, on an engine that will not sustain statically on any other fuel delivery method.

I take issue with the proof coming from your thrust stand. True, there is a net posetive mass flow out the tail, as in a ramjet or, ready? a "pulsejet" in forward velocity.

Your thrust setup, no matter how you have done it is a mass (the engine and all supporting bracketry) on a spring, and has a natural frequency much lower than the thrust oscillation you know the engine has. Even if it did cross zero (which it does not unless you subtract the intake massflow from the exhaust massflow), and I know your loadcell is up to it, your setup will never dip below zero because the system hasn't the frequency response.

Best regards!

[luc]

He he he ..

Well ... I think this is the kind of debate that could go on for numerous pages and ages. So why don't we just go on with what diffinitions we have now ... Such as Lockwoods, pulse jets, pressure jets and others ... Anyway, for my self, I am quite satisfied with what we have now ... He he he.

I guess four years of testing got into me and that I am ready for damn good vacations ... So okey guys ... The pressure jet is a pulse jet ... he he he.

Have a good day ...

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

[Mike Everman]

True, Luc. Pressure jet is descriptive enough. Vacation? I thought you just had a honemoon, dude?

[luc]

Ha mannnnnn ... I don't beleive this ...

Vacation? I thought you just had a honemoon, dude?

You are a very funny guy ... Mike everman. You must be Canadian, for sure.

If working full time 7:00 to 16:30, completing a 3 months design contract, by working almost all night, getting ready to move my familly 500 Klm away in 3 days and getting maried in 11 days, sound like honeymoon and vacations for you ... Man, I don't want to know what is your deffinition of "Working". Nope, the honeymoon is still down the road Mike.

Nope, I was not on vacation. Only 3 days here before a finally walk away from this 4 years R&D project. I will probably run engine #4 and #5 a few more time by the end of the week, both patent request have been deposited to the US and Canadian gouverments and I am starting to pack my stuff now.

And beleive me Mike.... What is coming-up ... Is no vacations. W'ill talk vacations in a few years ... If you don't mind.

It will just be hard for me... To leave my 5 little babys behind ... Welll, let say 3 babys and what left of the first 2 ... He he he.

But I am satisfied ... My job is done. Now it is up to does production and marketing guys to do their's.

Okeyyyy ... Funny Budy

Cya later ......

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

[jim]

I agree. Really, it doesn' matter whether you call it a pulse jet or
a pressure jet or anything else. What is important is how much thrust
it produces, how much fuel it consumes, and how does it compare
to other jets of all types. Still, I would like to see some data on
dynamic fuel consumption. Jim of the great USA!