IKnowNot'ing

I certainly don't want to discourage Richard. He just seemed to want to know what he was up against in term of engine management. But I'm sure a lot of knowledgeable people in his vicinity can come to help him dealing with that aspect so he can concentrate on the supercharger design and development.

When tests start on this axial supercharger, and in order to allow the community to compare this novel (I' never seen something similar before for automotive applications) supercharger against competitors, it would be nice to obtain the following technical data from you Richard :
- Power requirement vs. air flow at different discharge pressures and s/c RPMs
- Temp difference (outlet - inlet) vs. air flow at different discharge pressures and s/c RPMs
- Volumetric efficiency vs. absolute discharge pressure at different s/c RPMs
- compressor lag at various engine speeds (transient behaviour).

For an example of dynamometer set-up to conduct such tests, I refer you to the SAE tech paper # 850244 of which I have a copy.

For other aspects discussed in some posts above, as already mentionned in my previous post, I agree with Babylou about the need to keep the OEM ECU on a aftermarket turbo/supercharger road application. I would however point out that the rough character of some project run with aftermarket ECUs is usually due to :
- a lack of knowledge of how to calibrate an engine management system (EMS)
- lack of proper procedures for calibrating an EMS
- lack of development time
and not to the ECU itself although it is true that they usually don't offer the same level of refinement and confort as OEM ECUs.

IKN

Richard Paul

iTrader: (5)

IKN,
First, thank you for your posts on the EFI subject. It started some flowing of information. I belive Turbine Pwr thoght if this discution a few weeks a go.

I am personally not as worried as everyone else is. It can be solved. I can't say anymore.

It's funny that you seem so well informed on most things but never heard of an automotive axial flow supercharger. One of the original purpose built superchargers was The Latham. firat built in 1956 it was produced for almost every type of car and boat at the time.

Problem was cost and Norm Latham stoped building them in 1965. I bought the company in 1982. I redesigned the unit completly and started sales in 1983. In total there were over 1000 units built. That is not many but consider costs it was good sales. They always sold for twice what others did.


In fact most of all those sold are still running. I get calls all the time for parts and service. Several sold on E Bay recently one was as old as 1958. And still usable. Now those old '50's units didn't flow enough for modern engine they were the best for thier time.

The production units I built in the 80's were fine for street cars of the era. As soon as I can get a scanner I will send you a copy of a test performed by Airflow Research for Peterson Publishing. This test was open to all manufactures who wanted to play. The rule was that they would put it on thier engine and it would be limited to 7 psi.

The baseline engine put out 320 hp. three other (all roots) companys showed The best of the roots made it to 392 hp.
My blower made 464. I flat doubled the increase of the roots.
I didn't do the test they did.

Next, I too have a copy of SAE 850244. If nemory serves me I think I agreed with thier ideas on the mechanical and data stuff but, not on test procedures. The methods they spec out will not work with the axial flow. Again I read a long time ago but that is how I saw it.

Next as to giving out all the data that we compile is not going to happen. While we will give out temp deltas and pressure ratios I doubt there is any positive reason why we should give out everything we learn.

On page 13 of my thread you will see a picture of two blowers in the 6 inch dia size. These are custom billet units one was built in 1990 the other in 1999. So I have plenty of past product to speek for.

This is another place I don't worry as much as the other people do. My big problem has been solved. With new manufacturing methods I can make the thing at a price competative with the others. While still producing a better product. The pictures you see on the tread are not just prototypes. This is the product, we are making with this manufacturing method. These sort of parts will be what a person gets. You can't get these sort of parts except for aero useage.

Also get SAE paper on centrifugal verse axial flow superchargers for aero usage.

Hope that answers your questions. If not just write back.
Richard

IKnowNot'ing

Richard, thanks for all these details. I will do a search on the internet about the Latham s/c. I really thought it was a novelty (brought to us by some 'mad' scientist or aero engineer). Your production of 1000 units since 83 therefore comes as a (good) surprise!

Re the tech data you compile, I understand and I'd be glad to buy the relevant SAE paper that you won't miss to publish when time comes! Note however that some other s/c manufacturers publish this kind of data. I have a few sheets in front of me here from Eaton and Opcon.
On this subject, do you have a ref # for this axial vs centrifugal s/c paper?

Richard Paul

iTrader: (5)

IKN,
I Will look for that paper in the morning. I'm sure it is at work.
Her if it goes through is a picture of what happens when you stall an axial flow compressor by pushing shear air across the face.
Damn it is too big I will try to make it smaller.

Drewstein

<---- Huge skeptic (lets see REAL numbers)

I'll put a twin-screw against your axial any day of the week. Which you haven't mentioned, and they're much more efficient than a roots as well. First reason I'm skeptic is you wanted to start with a Civic. The peak of performance. Second you're now working with the RX-8, a mid to high 14 second car. Some thing tells me that there would be more demand from car owners that are more interested in speed than the quality, handeling, looks that the average 8 owner baught their vehicle for. Also you're talking like a peak hp number is somthing to gawk at. The way boost ramps up on axial/turbo/centrifugal applications is why the REAL fast guys have roots blowers (4 second dragsters). And there's a reason twin-screw isn't allowed on those cars (to much power). Power under the curve my friend, will always beat a nice peak number.

To many pages not to have a single performance number or a working model for that matter. If you have one slap it on a motor, I don't care what it is, and give me the facts. I want parasitic drag numbers, real cfm, inlet vs outlet temps, and hp/tq gains.

Sorry for sounding like an ***, but the experienced of us have heard "this will make big power blah blah blah" then nothing.

IKnowNot'ing

It sure went through! I was not aware of a destructive stall related test for FAR certification. Was that failure on the GE90 intentional? It looks like it as there is some containment fairing around the compressor, as for a bird strike/ingestion or compressor blade failure tests.

RotorWheeee

Nice Picture
You just gotta know that gona cost some one.

IKnowNot'ing

It's gonna cost YOU everytime you fly a Boeing 777.

Richard Paul

iTrader: (5)

IKN, very impressed. You even knew what plane the GE90 engine came on.
Yes, it was intentional. Kinda dumb though, there isn't any way that there could be a complete 90 degree wind shear. Yet it's good to know they look at everything they can think of.

Yes, that is a "scatter shield". They shoot frozen chickens into the thing.


Here's a picture of a 747 that was just carrying a twin screw blower in the cargo compartment.

IKnowNot'ing

Cheating! After my years at Ford, I worked for 2 years at a SNECMA owned company. It supplies some parts of the GE90 (like a gerotor oil pump) and did a lot of engineering work on the compressor. I worked on the much smaller GE CF34-10 (trips to Cincinnati) after some crap military maintenance assignments (visited San Antonio and OC).

PS : good 747 picture, even better comment!

derwankel

NO SOUP FOR YOU. NEXT!

Hymee

iTrader: (1)

An absolutley fascinating read.

I am amazed at how I found this thread. I was kept busy on the "Roots" thread (although I am investigating and want to develop twin-screw), and Richard chimed in with a comment on Axial flow compressors. I know what they are from some basic knowledge of gas turbines, but had never heard of them, or the Latham before.

So I got really intrigued, and went to google and entered "AXIAL FLOW SUPERCHARGER" and guess what the VERY FIRST HIT IS??

This thread! I was amazed, and spend the best part of a few hours reading all your posts.

These are the sorts of things I would need to know to try and make a "theoritical" comparison. (Yeah - I know a practical comparison is best, but you gotta start a dream and a design somewhere...)

• For a given pressure ratio, what is the mass flow rate v's input shaft RPM?
• For a given pressure ratio, what is the inlet/outlet temp difference v's input shaft RPM?
• For a given pressure ratio, what is the power required to turn the input shaft v's the input shaft RPM?
• All of the above at different pressure ratios (say 8, 11, 14 PSI)
• What happens in this design when at low flow rates you crack the throttle wide open and then engine sucks high flow past all those "little wings". How does this design cope with that. I guess this is all related to the "stall" phenonemon.

(I will make a point about reading all the docs Richard posted)

To me, those first are the 3 most important specs I need to know about how the unit performs.

I know that these sorts of designs are the "piece d' resistance" best practice for gas turbines, and cope with vary high RPMs and very high pressures, as well as high efficiencies. I also know that gas turbines are best suited to constant RPM (aka cruise) type operation.

Unfortunatley, I am looking for a solution that can get me more low end grunt and not go stratospheric at hi RPM's. Perhaps that is not achievable. Practical experience will tell.

Looks like 3 choices so far...

• Constant boost (Positive Displacement Supercharger)
• Linear boost (Axial Flow Supercharger)
• Non-linear boost (Centrigugal supercharger/turbo)

I also remember sitting in high-school english classes, ignoring the lesson, but instead drawing designs with other petrol head mates. We wondered about an axial flow turbo design, where the exhaust gasses spin the compressor in the same manner as a gas turbine. I distinctly recall a little diagram we drew outlining this concept. Has anyone any history/links on this applied to automotive forced induction??

Turbos, with their centrifugal compressors and (heck what do you call the bit on the exhaust side???) seem to be the best practice for piston engines. But surely they are not the be-all and end all. I like to see some novelty and new ideas (or modern application of proven technology).

Cheers,
Hymee.

Japan8

Hymee... it's called an impeller if I am not mistaken (please correct me if I am).

Richard Paul

iTrader: (5)

To show Drew that I proposed alternet supercharging to the NHRA about 5 years ago. I even made a case for saftey. They are not interested. So here is a paper I prepared for them.

By the way the other side of a turbo is the turbine. There are some people out ther who for fun make turbos into jet engines by adding fuel and a spark plug.

Here is a quiz for you drew. multi choice. A. axial flow
B. centrifugal C. roots D. twin screw.

What type of compressor is run in each of the following aircraft?

F 4
F 5
F 14
F 15
F 16
FA 18
F 22
F 101
F 111
F 117
F 86
A 7
A 10
B 52
B 1
B 2
707
727
737
747
757
767
777
AB 300
AB 320
MIG 25
MIG 29
Marage F1
Saab something or other
SR 71
DC 10
MD 11
MD 90
That's about all I can peel off the top of my head.

Answer: All but one have A. axial flow.

The winner will be the first guy to name the plane with the centrifugal.

Richard

04RX8DRIVER

Nice Richard! RG keep putting the less informed people in their places! LOL

IKnowNot'ing

I looked at every one of them for tha last 20 min : can't find it!! I thought it was the F86 to start with, but no, it isn't.

Richard Paul

iTrader: (5)

It is the F 86. Sadly I lost my very best freind of 25 years in one of them. Dave Zeuschel master engine builder of blown fuel Chryslers and later of Merlins and P-51's themselves.
He sold his own P-51 and built the F 86 from a shell he found at a military school. Lost his life at an air show in the thing.
Z was responsable for a good number of the Reno Mustangs.
The first plane he built was the Bearcat tha Gredemyer set all the records with and won Reno many years in a row. That plane is in the Smithsonian.
His Mustang "Stilleto" held the world closed coourse record for most of the 80's

Hymee, that was you in my english class? No wonder I failed, we just enabled each other.

RAP

ranger4277

I thought it was the F-86 too, then I looked it up and found this page:

http://www.acepilots.com/planes/f86_sabre.html

To quote the site:
Q: I heard that the Russians copied the British 'Nene' jet engine. So the Sabres were basically fighting against British engines.

Mahurin: The British scientist, Sir Frank Whittle, had developed a jet engine that worked on a centrifugal compressor. If you looked inside your washing machine and saw that thing rotating around, in essence that was the thing that compressed the air that went through burner chambers and then out the back end of the MiG-15's engine. The only way to increase the performance of that engine was to increase the size of that compressor. When you did that, you increased the weight of the turbine wheel. Then the engine got to the point where its increased performance didn’t compensate for the added weight. So the centrifugal compressor engine eventually became obsolete. But during the Korean War, it was pretty good for the MiG-15 and light enough so that it had a high performance.

But the F-86 was powered by the GE J-47, an axial flow engine. This engine is like having a whole bunch of electric fans stuck together, pumping air in and increasing compression. That compressed air goes through the area where they have gas, and ignites the fuel, and that goes through turbine wheels on the back end, and that provides the forward thrust. Eventually, the world embraced the axial flow engine.

My intent isn't to say Richard is wrong, actually this blurb backs him up! I just don't know the real answer on the F-86 now. The first models probably did have centrifugal, until they realized they weren't good enough.

babylou

I'm sure the F-86 was a GE axial flow assembled in Ohio.

Richard Paul

iTrader: (5)

Man do I feel dumb. I was inches away from the compressor section on Dave's F 86. One weekend I stoped by the hanger and the tail was off exposing the rear of the engine. What was happening was a new Burner ring was being installed and I was inlisted to help. I never even thought to look at the comp. section. It wasn't really visable from the rear.

It seems that GE made two engines at different factorys. One with a centrifugal compressor at the Lynn plant. Another with the axial built at Schenectady. In 1943 GE decided to go ahead with the development of both because they felt the centrifugal will get done first and help win the war. The axial because it had more potential.
Both engines were designed for 4000 lbs thrust with 78 lbs/sec air flow. CALLED THE I 40 THE CENT TESTED IN JAN 1944 WITH 4200 LBS THRUST.iT FLEW IN THE xp-80A. But only a few dozen Lynn I 40 engines were built when the Schenectady plant produced 300 engines now named the J33. The axial engine was now called the TG-180.In 1946 the TG 180 was begining to work right and wasnamed the J35.

The biggest producer of J35's at the time was Chevrolet. For the mass production Allison was tapped. After being relived of production GE went on to design a J 35 type engine with the same frame size. Only to be rated at 5000 lbs thrust.

This had an uprated axial flow compressor of 12 stages flowing 92 lbs and a Pr of 5.This engine by 1948 became the J47. This engine progressed in power until the mid fifty's. At the final build spec it had Pr of 7 and flowed 142 lbs/sec. There were 870 of this spec engine built they produced 9200 lbs of thrust. All were built for the final F 86H.

So are you all confused?? It's a good bet that only very few F 86 were ever built with the early Lynn engines. Probably only test planes. So I was wrong, All production F 86's were axialflow J 47's. To complicate it further the J47-27 was later designated the J 73

There were about 36,500 J47s built.

babylou

The above profuse data let was Richard's way of admitting he made a boo-boo on the F-86 engine but he still knows his stuff. I'm cool with that.

olddragger

iTrader: (3)

RP
I am impressed! I dont say that a lot. It seems from the posts that not only do you have creditable working experience but you also are very creative. Nuts and bolts man and idea man all in one! By the way did you throw a paxton on your lawnmower yet!? LOL!
This is my 1st "tuner" car. In the past if I wanted performance I was into NA cubic inches. My favorite engine was the chev factory396 (L 88 i believe I may be wrong there) factory aluminin heads etc. Open up the breathing on it a little and it would scream. I just hated those solid lifers and burning plugs up every week! How things change. I appreciate you taking time aswering my laymans questions and I will continue to follow your developement. You may be making history here man (again).
INK thanks also for your info. You have been a support. Keep brainstorming. There can never be too many questions as long as you never loose the belief.
olddragger

Richard Paul

iTrader: (5)

Drewstein, I just finished dinner and I.m talking to Torque my golden retreiver. I'm thinking about your post and Rotorygod just about handled it much better then I could have. There is one more thing. "REAL fast cars". Well drag racing is the bottom of the ladder for technolagy. It is the Fred Flintstone of racing. I can say this because I have a drag racing background.

I've mentioned Zeuschel who pioneered blown fuel Chryslers. Another life long freind just happens to be the man that started the custom GMC type blower industry. By that I mean the first one to build his own case and truely set all the clearences. Also developed the nylitron strip inserts, Larry Bowers.

4 seconds of engine life. Impressive. Every week the advertizments up the HP claims. No one knows, and it doesn't matter. The only drag racers that show me any real smarts are the Pro Stockers.

You want to talk about real engines and real power. Look back at the turbo era of formula one. The 80's. How about 1200 hp from 91 cu in. That was qualifying trim true but they were only detuned to 1000 hp and then ran a 200 mile race. The numbers again 1500 cc's over 1000 hp and they run for two hours.

They did not use roots blower. They ran little bitty turbos on 4 and 6 cld engines. these were about the size of your drag race blower by itself. One more thing they run on gasoline.

Today they run 183 cu in engines and no blowers. They are a little down on power at 925 but they are more drivable. more stuff? how about they run practice qualifying and the race on the same engine. they run 19,000 rpm with no valvesprings. The best number is this one: the engine weighs 200 lbs.

These are the FAST ones. everyone else is just pretending including myself.

Hell I'm more impressed with the NASCAR good ol' boys. they get 820 hp out of 357 cu in with pushrods and a carburator. I can't fathom how they run 500 miles at 9600 red line with pushrods. amazing. They're good. No engine managment, no electronic help.
A carb and a distributor truly amazing.

I'm done, gotta walk my buddy now.
Thanks to everyone else for all the support.
Richard

kyllc

Well I'm a first timey, and Ive read all 15 damn pages of this ****, most of it was empty characters that my febal mind couldnt understand. (hope i spelled febal right). Any ways i foudn this forum to find mods for rx-7 (3rd gen) and I am always interedted in buying new, hence rx-8. I knew from day one of rx-8 release that FI is a must for any engine because excess is never enough. Back to point, mad props to Richard for doing your thing, i wish you the best of luck on this project. And as much as i would like to support your AF supercharger I have no rotary of my own to put it on. But like ym pops always said it aint magic its money that gets things done. Or as someone stated earlier, cant remember who or on what page, its persistance over intelligence. So again, Thanks to RP, rotarygod, olddragger, babylou, IKnowNot'ing and ajax. You guys drained 3 hours out of my life catching up on this whole thing to only come away with the fact that the Axial Flow S/C is damn pretty all polished up. Lol good luck and thanks for the great read and dones of facts and formulas and pretty pics. Peace and Elbow Grease - Greg

kyllc

PS I dont know how i posted to this thread but my name isnt Kyllc. But I will be staying intune to this thread for history is in the making.