Yeah, the Air Force decides if people can fly or not by putting them in planes... not by having them move a square around.

 

Well, I have a beta version of the Cobb Tuning AccessPORT, and I can re-flash my ECU at will. Maybe a beta of the AxialFlow Supercharger won't be far behind.

 

From earlier posts I think there is more to be done than just hook up an Accessport to the AxailFlow S/C. The entire unit needs a redesign/re-fab speced to the high flow char. of the rotary.

This project is still on the books but I expect RP to focus on other jobs that may be closer to production than this one for awhile.

Just my $.02

 

I have no idea who your talking too...

C.H.R. => Me

 

I understand that tuning is not the only issue but at one point it was an issue, and I dont think we ever heard from RP that he had actually found an ECU management system that he was happy with.

I would hope that if RP decides not to work on the supercharger "for awhile" that he would let us know. There seem to be a number of people that only want this supercharger on their car.

 

Can somebody explain why the Axial Flow Supercharger will not be produced?

Note- Well, thank goodness Hymee seems like he might get his kit out one day.

CRH, makes it seems like it was not producing enough HP or didn't work. I thought they had this thing on a test car, dynoed, etc...

I was thinking it was waiting for the Cobb AP to come out. Now that the Cobb AP is about to be released, what's the hold up?

 

Thanks CRH.

I looked back at the previous posts also, because there was a time period that I missed some important info.

So, it appeared RP miscalculated the amount of air needed to create power when designing the AFSC, because he was basing his design assumptions off of piston engines.

The present AFSC does not develop boost until around 6,000 RPMs.
It appears an attempt was made to see if the problem could be resolved by tuning the ECU. Which was the hype concerning the Cobb AP was all about. But, this appeared to fail.

It was then apparent that a redesign for a new AFSC would have to be done to meet Rotary engine specifications. However, he already has invested a tremendous amount of money and time in the "old" AFSC. It also seemed it would be very difficult to redesign a new AFSC to the operating parameters of a rotary engine.

I think that is it. Sad though... Well now their is only 1 other "SuperCharged Rotary Jedi" left. Hymee.... keep fighting the good fight.

It does seems like he might try to see if he can get the present AFSC to work in a piston engine. There was interest in getting it to work in a Honda. However the issue of cost and time invested comes back into the picture.

RIP Rotary AFSC. Note- May you find a good home in a piston engine one day.

 

I wanna put an AFSC on an LS1 /LS2

 

So should those of us that have been waiting for this supercharger be looking at other options at this time? I would really like to hear from RP whether or not it will be release and maybe a timeframe.

 

Haha, let's not get into that debate again

 

i remember somewhere that a car was custom built with an axial flow charger in the 80's. The name Chamberlain Searcher comes to mind. It has the AF blower and peak hp is 712 @ 6750 rpm. I don't know at which rpm the boost starts.


Eric

 

Thanks Charles for the explanation. It's been an interesting ride along the AFSC highway and I wish Richard the best of luck. Much better to have some understanding of the project's limits.

I still can't forget the brief ride I had in Pettit's prototype charged 8. What fun.

 

I wish Richard would just come on here and say"Sorry folks, this ain't going to happen" and close this thread. Leaving it open like this leaves people with hope. I know I have been a big supporter of this supercharger and have read every post here.

 

I completely agree.

 

CRH, "A little knowlage is a dangerous thing" wes carved in a granite arch at some school I went to once.
You are wrong on almost everthing. First of all I have not given up on the Rx8. Next I never said that I was looking for an engine with less rpm range. That doesn't even make sense.
No matter what is on you have to limit it to the engine red line, so the rest is relivent.
I did say that jet engines have an advantage in their limited usage of revs but that just ment that my research was harder. I had to go where others didn't.
That doesn't mean it can't be done. There are ways to bend the off design around in the operating range.
First of all you notice that we don't have the pressure ratio per stage of a gas turbine. That is because we need that higher operating range so we sacrifice utilization of the axial volocity. The camber and AOA plus solidity are factors also. There are so many facets to the axial flow equations that it really can't be understood without background. Not to insult anyone but to understand it you'd have to have worked with aerodynamics in a serious way.
This is even harder than a wing to design. In this case you have to throw in the varying inlet pressure and positive displacement negative discharge.
So what's the problem? I simply didn't know how inefficient the rotary was when I started this.

Something just came up and I have to leave. I'll come back and finish this tonight.

 

thanks Richard- and id still like one in my car.

 

good to know! ...my kids' college fund will be untouched until then LOL

 

Mr. Paul? Who is that? You mean Richard?

 

there are some cool pictures on the website of what looks like a kit. what else has to be done from there? tuning?

 

Yup we used 3-D Computational Fluid Dynamics packages as well a experimentation proven factors when doing basic 2-d work for the design concepts at Pratt & Whitney. The designs are very complex.

Richard when I saw your design the biggest difference I saw from your design and most of the compressors I've seen is yours only uses the airfoils for compression. Most of the large axial compressors use a converging nozzle as well through the compressor stages. It gives you more compression with less stages and also allows you to make shorter, stouter airfoils as the pressure rises so they are stiffer. Any reason you didn't decide to use this?

 

Where was I?
First off I meant no disparage to you Ray, I have always admired your careful planning and excellent documentation of your work. You're a thinker and I've said in the past I like your work.

Next what I was saying is that we originally designed this compressor for the Honda S2000. When we decided to do the 8 instead we had no idea how inefficient the rotory was and it needed much more air. So we went along increasing the blade legnth in the same envelope instead of running new numbers for a clean design. Everyone has done this, stubbornly insisting it can be made to work. It's the hot rodders mentality, just keep putting more and more of everything and be shocked when the crank falls out.

Long story short, after making the blades longer and the base smaller it became unstable with the clearances we wanted to run. When finally someone here ran some numbers we found 10,000 G's of acceleration on the damn thing. With this material and as light as it has to be, it will not work.

So in order to get less G's and more blade it has to get bigger in diameter.
This takes new tooling and money and time. That's where we are at and why it takes so so long. To get where we are took a lot of compressors and a lot of other parts, all prototype but that's how you learn. We shall never get a return on the Rx8 investment but it's been fun. We will finish it because we are stupid.



Shaunv, We do use defusion in our designs. You may not be able to see because it is a very small amount. That is because our compression ratio is small compared to regular gas turbines. That goes back to what I said before about having to give up alot in order to operate off design so much. You could make as much pressure in one stage as we do in four. But you would have stalls in a hundred places on a daily drive. I'm not going to give away 20 years of work to tell you how and why. If you look closly at a rotor you can see the last blade compared to the first is shorter and has different geometry. All the stages use different geometry including rotor to stator. That is 8 different programs per 4 stage blower.

Worse then that is we do it by hand not having the expensive programs we would like to have. I do have a good calculator and put my sliderule in a draw.
How many of you guys have seen a sliderule? It's kinda like a 45 record or an 8 track.

So everybody buy a master cylinder brace to help fund the R&D on the supercharger!!

 

Mine are in my parents basement, along with my t- frame, triangles, protractors, etc. I think there are several old erasers, (with nothing left on them), in the box also.



Those were the days for sure...

 

Richard,

I am so dissapointed. All this time I thought you did all the math in your head. Then I find out you sold out to a slide rule...

LOL.

Keep up the good work.

Cheers,
Hymee.

 

Seen, like in a museum?

I kid...

 

Ok, I do not know where my slide rule is anymore. When I went to high school and early college, you could tell the real geeks because they spent several hundred dollars for a calculator. My money went into BB Chevy parts.

As for the brace, I hope my bit of funding helps.

We want to see a supercharger as unique as the rotary is!