Pressure Gain Combustion (Now Proven)

[Mike Everman]

Yes, I am going to Magnetewan River near Parry Sound, Ontario.

[luc]

Yes, I am going to Magnetewan River near Parry Sound, Ontario.

Okey,

What date? ... For trouth fishing season closes september 1st here.

By the way ... Last Sunday, I went to a litle river 1/4 mile next to my house and walked down that river with my weaders and rod to catch my 20 nice trouths limit, many of them between 10 to 14 inches long.

A litle 3 hours walk down stream with water up to my waist ... Talk about fishermen paradis ... He he he

Hope you have nice fishing too,

Cya,

[luc]

Greetings guys,

Hear this ... he he he ...

Did another test today using a smaller turbo for our small engine and guess what ....

Above 95,000 rpm ...

And this ... Not even being at full power. At engine Idle power, the turbo turns apprx. 50,000 rmp and I reached above 95,000 only at 50% engine power.

Tomorow I will do other tests to records temp., noise, rpm readings and will push that turbo to engine maximum power ... he he he ... Hope the turbo won't blow-up for it is rated to a max. of 115,000 rpm. Our tubo expert guy who's working with us on this, believe that with our engine, this turbo will break a speed reccord for its kind and model.

Anyway, will bring you a nice movie of this tomorow ...

He he he ... Yessssssssss ... 95,000 rpm .......

Regards,

Greetings guys,

Okey ... Always in a spirit of pure honesty and to provide accurate knowledge ... I have to revise or correct that post

Even if at first glance, I published the impressive 95,000 rpm above, the real figure now points out more towards 15,000 rpm and even if at this point, we are not all conviced about that too

This correction is required following many series of test where we noticed the speed meter we are using shows "Jumpy" and unstable readings

After deeper investigations on that speed meter which an IR speed meter that works by reflection from a reflector tape stuck on one of the compressor blade, we realized that :

1) The reflector tape behing on an "Angled" blade, reflects the IR beam away from the meter and onto the compressor inlet walls.

2) The reflector tape is a near grey color and very close to the compressor blade's color and also the compressor's inlet color, which is also alluminium grey and polished.

3) We have noted that more the compressor is spinning, the compressor's inlet mouth glows red from IR beam reflected away by the reflector.

4) For this, we believe the meter is picking up all sorts of IR beam returns, some from the reflector, some from the other compressor blades and other from the compressor inlet walls, which makes the meter to indicate jumpy and inacurate readings.

To solve this situation, we will either spray the compressor and inlet with doll finish black color or, we will use a real turbo speed meter manufactured for this purpose.

So this said ... Sorry for the misleading information above even if still not sure if the above is "Missleading" or accurate at this point, but I taught it was necessary for me to be transparent at this point

We will post the real results as soon as investigations is completed and when we will have the accurate speed figures.

Regards,

[luc]

Good effort Luc. Just a crappy picture but here's the one I built for my degree:



I didn't get a chance to measure any rpm's but it ran pretty fast and glowed up like yours!

I'll buy you a beer, we can toast to everyone who says it can't be done!

Heyy Jonny,

Sorry for not answering or complementing you sooner ... I am up to my nose here with the ongoing tests.

That's a very neet setup Jonny ... How far are you in your testing with this baby??? Do you have a video of it running??? I am very curious to see a valved pulsejet spinning a turbo.

By the way Jonny, don't get to concerned about that "Glowing Red" turbo for I recently made great new discovries about turbos and they can take the heat given you have a good lubrication and oil cooling system. Next to the bearing, these baby will take alot of heat and almost anything you can trow at them, unless "Everything" is a handfull of ball bearings into the blades ...

Nice setup Jonny,

Regards,

[Mike Everman]

Even if at first glance, I published the impressive 95,000 rpm above, the real figure now points out more towards 15,000 rpm and even if at this point, we are not all conviced about that too

I thought it stopped spinning awfully fast in the video!

[luc]

Even if at first glance, I published the impressive 95,000 rpm above, the real figure now points out more towards 15,000 rpm and even if at this point, we are not all conviced about that too

I thought it stopped spinning awfully fast in the video!

Hi Mike,

It does indeed ... But obviously, not to what we were thinking.

The first clue that rose our concern, was that we could'nt hear the "High pitch" wistle noise know to turbos when they are really spinning. So, or question was "How come we can read 80,000, 85,000 and 95,000 rpms on that meter and still not hear that high pitch wistle noise?", which lead us to put more attention on the meter it self to realize it was acutally jumping from 9,000 to 95,000 rpms. And then, our attention got to what we believe to be an IR reflection problem.

None the less, this is really not a concern for us at this point for the concept works really well and we are just at a point where we now need to "Trim" each turbos for maximum rpms. The two setups are now scheduled to spend a few days at this turbo specialist shop, where they have real and accurate speed sensor and a wearhouse full of different turbos, turbines, compressors and castings and they will have fun triming those.

By the way, I was stund to learn that they do "Trim" each turbo like jet engines. The differences is that for turbos, they need to match wheels and castings to get max. performances, where this is done by the FADEC through the "IGVs" (Inlet Guide Vannes) for jet engines.

I always taugh turbos where coming out of factory as fix models but they are not.

Man ... The amount of knowledge I am getting on turbos is unbelievable ... I simply love it ...

P.S : Mike, remember our big engine (11,700,000 btu/Hr, 337 lbs. thrust and 7 inches tail pipe) ???, Well, the guy thinks he also has a perfect super monster turbo for it ... ... But that's somewhere down the road

Regards,

[racketmotorman]

Hi Luc

Just checked out your video of the engine , very interesting .................I hope I can contribute a coupla cents worth on the subject as you progress .

My turboprop PJ experiments failed even though I was able to get my ~6" dia homemade axial turbine to ~20,000 rpm ( tach recorded) , this was with no load and it did take a long time to spooldown once the engine was shut off , though with loading ( prop) it was pathetic .

Theres pics of my turbopro PJ here ,....... http://www.racketmotorman.turbinebuilder.com/

http://www.racketmotorman.turbinebuilde ... hp?album=5

Also a video of it running somewhere on the site

As far as measuring torque from a "freepower " turbine , simply attach a 12 inch torque arm where the comp normally fits, fit a spring balance to the end and readoff the "foot pounds".

Freepower turbines develop ~ twice the torque at stall as they do at full rpm , with a linear reduction as speed changes from zero rpm to max .

So , if you develop 10 ft lbs at stall , you'll only have 5 ft lbs at max rpm .

And yes, turbos do need tuning when made into gas turbines , but trying to judge the exact sizing for your particular situation will most likely be a trial and error exercise unless you know the mass flow and pressure drop across the turbine stage , you'll probably need to start with the largest A/R scroll for that turbine and slowly try ever smaller A/R's untill you find what works . The smaller A/R's will need a greater pressure ratio.

Please don't exceed a turbine inlet temp of more than 900 deg C if extending the rpm , and try keeping rpm to a level where tip speeds are below ~1,500 ft/sec , which from the vid of your engine appears to have a reasonably large turbine , so probably ~60,000 rpm for safety sake , unless you don't mid tips flying off .

All the best with the experiments , I'll be keeping an eye on your progress to see if you can succeed where I failed )

Cheers
John

[luc]

My turboprop PJ experiments failed even though I was able to get my ~6" dia homemade axial turbine to ~20,000 rpm ( tach recorded) , this was with no load and it did take a long time to spooldown once the engine was shut off , though with loading ( prop) it was pathetic .

Theres pics of my turbopro PJ here ,....... http://www.racketmotorman.turbinebuilder.com/

http://www.racketmotorman.turbinebuilde ... hp?album=5

Also a video of it running somewhere on the site

Hi John,

Well ... I looked at both the movies and pictures and I don't know why you say it "Failed". I personally think you're on a road to somewhere here and you have achieved great steps. Looking at you "Turbo prop" experiment movie, the first thing that came to my mind was "This engine needs to breed better" meaning, don't forget PJs induces fresh air by both their intake and tail pipe. Personnaly, I would install an "Augmentor" or "Ejector" type ventury attached to you turbine inlet to give this engine more chance to suck that fresh air from its tail pipe, which at the same time, would induce colder air into that turbine. Don't forget that cold air expands when heated which if well timed, expands into the turbine and increase pressure as it also cools down your turbine. But, that's just a taugh.

but trying to judge the exact sizing for your particular situation will most likely be a trial and error exercise

I know ... This is why our two setups are going to this "Turbo Specialist" where they will match turbine and compressor wheels and housings trying to get the best match for best rpms and torque.

Please don't exceed a turbine inlet temp of more than 900 deg C if extending the rpm , and try keeping rpm to a level where tip speeds are below ~1,500 ft/sec , which from the vid of your engine appears to have a reasonably large turbine , so probably ~60,000 rpm for safety sake , unless you don't mid tips flying off

Roger that ... But don't forget we are not at the stage of hadding a prop yet, but mostly to the stage of turbo generation only. Gearbox and props will come later and only after we have answered actual GLC's commercial needs.

All the best with the experiments

Thanks ...

I'll be keeping an eye on your progress

You are more then welcome to do so ...

to see if you can succeed where I failed )

Stangely ... I see success where you see failure in your project. But again, it all depends from where you look. Personnaly, I just think you are going somewhere, but as a piece of advice ... Keep the steps simple and small and do them one at the time.

Thanks for your encouraging comments John,

Cheers and regards,

[racketmotorman]

Hi Luc

LOL..... I guess I felt I failed because I couldn't get usable power out of the engine , despite the huge amount of noise it made along with its appetite for fuel ,compared to my turbine engines there wasn't any power coming out the tailpipe .

I have a suspicion that PJs develop their thrust more from "pressure thrust" further inside the engine, rather than the "usual" mass flow times velocity at the exhaust like a turbine engine does.

Without any significat pressure ratio being available for accelerating gases across the freepower turbine , one needs to utilise the available velocity exiting the tailpipe as the power producer .

An interesting thing that did happen with my engine was the freepowers rpm increased by ~10% when the "gap" between the tailpipe and freepower inlet was closed off by a sliding sleeve , making the engine "breath" back thru the freepower , rather than thru the "gap" .

The freepower was designed to have cold ambiant air "follow" the hot pulse thru the freepower , in an augmenting fashion , but it didn't appear to happen all that successfully .

Turbines by their very nature require gases to be accelerated by a pressure reduction , unfortunately theres no significant static pressure issuing from the PJ exhaust that can be expanded and accelerated .....this is why I'm a little sceptical of any turbo/turbine expert being able to give hard advice on what configuration of comp/turb for you to use successfully .

What sort of static pressure do you have entering the turbine ?? ......you'll have a fluctuating total pressure from the dynamic components of the pulses , but the mean static pressure is what'll be needed .

Also with your fitting a comp/turb combo to your engine , you'll need a faily large plenum between comp and engine to smooth out the different airflow requirements between comp outflow and engine inflow , on turbocharged single cylinder IC engines the plenum needs to be several times the swept volume of the engine , otherwise the outflow of the comp is compromised from the intermittent demand of the engine .

Your advice of "one step at a time" is very sound advice , I try to adhere to it , along with keeping good records of adjustments/additions/modifications/testruns etc etc . , nothing worse that not knowing which change made which result )

All the best with the testing , if you'd like some more input from my experiences , I''ll be only too happy to throw in my 2 cents

Cheers
John

[luc]

Woowwww ... Very long post John ...

Again, I will try to separate it and keep as simple as possible ...

LOL..... I guess I felt I failed because I couldn't get usable power out of the engine , despite the huge amount of noise it made along with its appetite for fuel ,compared to my turbine engines there wasn't any power coming out the tailpipe

My advice here ... Never compare apples with orange ... Especialy when trying to evaluate achievements. There are simply no comparisons between turbines and PJs ... BUT, even if PJs seems to be no match against turbine, they will provide numérous advantages (i.e : Simplycity, low cost, low maintnance ... ect ect ect) compared to turbines. It all depends what you want to do with it and falls down to "Applications".

I have a suspicion that PJs develop their thrust more from "pressure thrust" further inside the engine, rather than the "usual" mass flow times velocity at the exhaust like a turbine engine does

They use both. Turbines will often provide higher mass and lower speed where PJs will provide lower mass and higher speed when talking about exhaust gases and or thrust. Again ... Two different story here and again, it all depends what you are looking for (i.e : Application again).

Without any significat pressure ratio being available for accelerating gases across the freepower turbine, one needs to utilise the available velocity exiting the tailpipe as the power producer

True ... But again, maybe this is sufficient for the need being. One note taugh ... At one point when testing, we realised that when loading the compressor with a restriction on, the actual turbo rpm increased by more then 20% ... . Which lead to conclude in two possibilities, 1) being that pressure was also increased in the turbine wheel, thus, higher rpm too 2) being that fuel combustion was not all completed at the engine, so loading the compressor actually favored residual combustion "Inside" the turbine housing. We are still investigating this one.

An interesting thing that did happen with my engine was the freepowers rpm increased by ~10% when the "gap" between the tailpipe and freepower inlet was closed off by a sliding sleeve , making the engine "breath" back thru the freepower , rather than thru the "gap"

The freepower was designed to have cold ambiant air "follow" the hot pulse thru the freepower , in an augmenting fashion , but it didn't appear to happen all that successfully

Possible and maybe true for your actual setup. Keep in mind that when playing with PJs (i.e : Thermo Acoustic engine or burner), the word "Acoustic" take all its place and must always be seriously considered since these devices are highly sensitive to thier immidiate suroundings. This means, that one must always make sure that all is sychronized and well tunned ... Otherwise, you might loose all your power right there.

You have to tweek these things and trust me ... The power or max operation band is very narrow and unforgiving too. Experience has taught me with these engines, that there is no such things as "Grey area" or "Inbetweens" with thermo acoustic engines ... It is always a Yes or NO or Dead or Live situation and/or results. This is why I have always said ... "Go slowly or you might miss the right Spot" ... One step at the time and make these very small steps. Maybe this is why we have succeeded with the pressure jet ... Where so many have failed. Don't try to build Rome in one day and keep the posting short, one subject at the time ... He he he

Turbines by their very nature require gases to be accelerated by a pressure reduction , unfortunately theres no significant static pressure issuing from the PJ exhaust that can be expanded and accelerated

Sorry to say this and you know me being a "Direct" guy ... But maybe this is why you keep having that "Failure" feeling for you always keep comparing apple with oranges ... Stop doing that and forget about turbines if you what to venture and play with PJs ... These are two different story here.

.....this is why I'm a little sceptical of any turbo/turbine expert being able to give hard advice on what configuration of comp/turb for you to use successfully

I am not and that's the most important for now. My goal here is to combine two different expertise here and without spoiling my mind with that "Turbine stuff". Don't forget that once, I use to be a jet engine technician for other companies and it is really hard for me too to seperate both concept. So this is why, this guy remains in his field of expertise and I stay in mine, keeping both minds clear ... He tells what he needs to have his turbo spinning and I tell him what I need for my engine to work.

What sort of static pressure do you have entering the turbine ?? ......you'll have a fluctuating total pressure from the dynamic components of the pulses , but the mean static pressure is what'll be needed

Not there yet ... Right now, we are aiming at two things first and in order , 1) is to have a combination that will first allow the engine to operate well, 2) achieving maximum rpm with maximum velocity. Then, we will start addressing "Pressure". I told you John ... One step at the time.

Also with your fitting a comp/turb combo to your engine , you'll need a faily large plenum between comp and engine to smooth out the different airflow requirements between comp outflow and engine inflow , on turbocharged single cylinder IC engines the plenum needs to be several times the swept volume of the engine , otherwise the outflow of the comp is compromised from the intermittent demand of the engine

Again ... I am not there yet ... But as an hindsight, it already works without one or better said, a very small one.

Your advice of "one step at a time" is very sound advice , I try to adhere to it , along with keeping good records of adjustments/additions/modifications/testruns etc etc . , nothing worse that not knowing which change made which result )

Good ... And a good advice here, would be for you to write down what I call a "Scope of Work" with all the steps you feel you should have, and then, have this scope review by someone who is not involved in the project so this guy "Unsecurity" (Especially if he signs the checks) will cut your scope into many more steps to make sure you won't miss one and/or ram forward to later have to come back.

Saddly ... There are still to many peoples trying to build an entire Space Shuttle before having the engines to push it. Designing is like making love to a women, you start slow, step by step to get her naked and well warmed-up before ... TAKE-OFF ... He he he ...
But I guess you forgot about all this ... Did'nt you ...

Heyyy ... It is always a pleasure reading you John ...

Regards,

[racketmotorman]

Hi Luc

Is there another earlier Thread on your engine , where theres more detail on what/how the engine/gas producer is constructed ?? ......as I'm not fully aware of all your running conditions and would like to be

Myself also being a direct guy, can only say that ,from the comments you've made so far you know very little about turbine engines , either 1 or 2 shafters )

Irrespective of the gas producer used, PJ or gas turbine , the turbine producing shaft horsepower requires certain conditions to produce power , if you don't know whats going in to it , how are you going to design it ??

The freepower turbine on my turbo prop PJ was designed using the best available data I could find on Site here and on the net with regards the efflux conditions of pulse jets

With my freepowered turbine machines , the gas producer was developed to produce its maximum thrust as a pure jet , running data was then collected , and that data then used to design the turbine stage to produce the shaft power ..........one step at a time , as you most correctly noted .

If you don't have even basic data from your base engine , such as the static pressure I mentioned , you , or rather , your turbine expert , will be flying blind when it comes to designing the turbine stage.

As I said in my first email ,....." I'll be keeping an eye on your progress to see if you can succeed where I failed" .


All the best )

Cheers
John

[Mike Everman]

Hi John,
It's been bothering me that the turbine is run from outside in. I know they're not made for it, but shouldn't the turbo be run inside out on a PJ, where gas velocity is its stock in trade, not pressure? There, I'd rather prove my ignorance by opening my mouth, than have folks suspect. ha

[racketmotorman]

Hi Mike

There are some serious problems with running a radial inflow turbine wheel with limited excess static pressure going in to it , the simple act of spiraling in requires a pressure drop ( law of physics) , exactly the reverse of a radial outflow compressor wheels diffuser where the high velocity air exiting the wheel is reduced in velocity with an attendant static pressure rise in a bladeless/vaneless diffuser .

This was one of the reasons behind my choice of an axial turbine wheel in my PJ turboprop experiments , there wasn't any requirement for a pressure drop across the stage as the usual "nozzle guide vane" ( NGV) set found in turbine engines , didn't have any "nozzles" requiring a pressure drop , they were just "inlet guide vanes" ( IGV) which turned the incoming gases thru a duct of uniform crossectional area so they exited at ~30 degrees to the turbine wheel plane , the blading of the turbine wheel was of a impulse variety , also not requiring a pressure drop , unlike the exducer on a turbo turbine wheel which will require a pressure drop .

Lucs choice of turbine will require a pressure drop unless its of such a large crossectional flow areas that the TOTAL pressure ( static plus dynamic/velocity) exiting the gas producers tailpipe can traverse the turbine stage without the required pressure ratio .

What could happen with a large crossectioned turbine stage is that there is some diffusion of the high speed gases exiting the delivery tube and entering the turbine scroll , creating a slight static pressure rise , which is then used in the reacceleration process as the gases spiral thru the stage .

Unless Luc has found a way around some basic laws of physics with regards our old mate Bernoulli and his principles , he's going to have problems once he tries to reduce flow areas to a degree necessary to achieve high gas velocities and mean turbine blade speeds necessary for power production .

I would imagine a simple Pelton wheel/turbine in the exhaust of Lucs engine would produce better shaft power than the radial inflow he is using .

Another arrangement is one similar to the setup on my bike engine ... http://www.racketmotorman.turbinebuilde ... hp?album=3 where the gases enter a scroll to the side of an axial turbine wheel ( no inward spiral) , but one with impulse blading rather than the reaction blading of the Allison C20 wheel I used .

I wish Luc all the best with his efforts , I hope he succeeds , but at present I see some glaring fundemental mistakes being made , which if he'd like some imput from me to help rectify , I'd be only too happy to give , having already walked some way along the road he's on )

Cheers
John

[luc]

Hi John,

Here's your answers ...

Is there another earlier Thread on your engine , where theres more detail on what/how the engine/gas producer is constructed ?? ......as I'm not fully aware of all your running conditions and would like to be

Look for the patent ... It is now public and I believe a guy here posted on it ...

Myself also being a direct guy, can only say that ,from the comments you've made so far you know very little about turbine engines , either 1 or 2 shafters )

Ouppsss ... This is where you're TOTALY lost and talking trough your hat John. But that's okey since we did'nt have time to chat alot before.

Okey ... Let me give you a bit of background here. First of all, avaiation is a 3 generation story in my familly and I am the 3rd (Hopefully one of my son will be 4th) and I have spent my life around my father since 6 years old and later on, did great project with him. Then, I became a piston engine mechanics on aircrafts such as DC3, DC4 and others smaller aircrafts, before being sub-contracted by PWC for their PW-118 high altitude flight test program on Embraer (Actually removed, striped down, rebuilt and re-installed 52 PW-118 engines for that plane) next to play with PT6 turboprops, JT5D and JT8D jet engines. Then, I was an Titan II GPU (Single shaft back to back empeller) engine specialist at Oerlikon Aerospace for 5 years, to later migrate to CEL Aerospace for 5 more years, a testcell specialize company who mostly design and build all PWC jet engine testcell (How can you design testcells if you don't know engines). In that same 5 years, I managed the Lakehurst Naval Base OTC (Outdoor Test Center) including a VATS, Gyro and Turn Table test beds for 2 years (And I did say "Manage"), in which we tested the PW-150 (5000 hp turboprop with no gearbox) for which there was only one single 6000 hp 18,000 rpm dyno in the world for it (This means ... Don't blow it), and then the JT15D, PW306 and PW308 on different test bench.

This background brought me to play with turboprops, turboshaft, jet engines and from single to multipule shaft (Up to 4 I believe) engines and their test instruments. So, correct me if I am wrong, but I think I have walked my road here.

Irrespective of the gas producer used, PJ or gas turbine, the turbine producing shaft horsepower requires certain conditions to produce power, if you don't know whats going in to it, how are you going to design it ??

No Shit ... He he he But who the hell told you that "I don't know whats going in to it"???? ... Heyyy, I designed this damn engine ... So, I sure know what,s coming out of his ass ... Don't you think????

Did'nt it occured to you that maybe I have my own plan of action ... So for once again, I will cross where others have sunk???

Okey ... let me ask you a 100 points question here (You can all participate) ... "Is it possible for a jet engine (Production unit, not a developpment engine) to at once instant, produce maximum thrust at maximum rpm, then 20 minutes later, produce almost no thrust still at maximum rpm???"

Please backup your "Yes" or "No" answers with a "Why" and "How" ... I will trow you the right answer later, but I will be nice to tell you there is a "Catch" in the above question, which is basycally the basis of my actual developpment.

The freepower turbine on my turbo prop PJ was designed using the best available data I could find on Site here and on the net with regards the efflux conditions of pulse jets

Same here, but except I don't have to run after Data as far as our PulseRam is concern ...

With my freepowered turbine machines, the gas producer was developed to produce its maximum thrust as a pure jet, running data was then collected, and that data then used to design the turbine stage to produce the shaft power ..........one step at a time , as you most correctly noted

Indeed ... But one point I need to point out here, is that you are playing with an "Axial" setup where I am playing with an "Impellor" ... Don't forget this ... Two different ball game here.

If you don't have even basic data from your base engine, such as the static pressure I mentioned, you, or rather, your turbine expert, will be flying blind when it comes to designing the turbine stage

Like I said above ... Did I ever mentionned somewhere that I or we don't know these basic data?

This said, here too I will ask another magique question ... Is it possible to find, measure or calculate PJs static pressure when at the "Pulse" or "Thrust" cycle? Again, please back your answer with "How".

As I said in my first email ,....." I'll be keeping an eye on your progress to see if you can succeed where I failed"

Well ... Only one comment here, for "Failing" is not an option and for I have peoples behind me writting down the checks and I certainly don't want a bunch of shareholders angry ... He he he ...

Have fun with the questions,

Regards,

[Mike Everman]

Agreed. I've gone down the impulse turbine path a bit, without calcs. Here is one that is machined, and one that is formed of sheet, which has an outer cylinder (attached and spins with the turbine) that is not shown.