Turbocharger oil solution for FSAE

[powered by wattard]

Hello all, below is a link to an SAE paper which I wrote which solves the oil control issues for throttled compressors for all you turbocharging guys who are having oil issues. It is sheduled to be presented at the World Congress in April 16-19 2007 in Detroit. It is specific to the GT12 but is applicable to all applicaitons. It also goes through some other aspects assocaited with turbocharger water cooling, control and some other stuff

2007-01-1562
http://eprints.infodiv.unimelb.edu.au/archive/00002816/02/2007-01-1562.pdf
Highly Turbocharging a Flow Restricted Two Cylinder Small Engine - Turbocharger Development

Regards
William Attard
University of Melbourne, Australia

[powered by wattard]

Hello all, below is a link to an SAE paper which I wrote which solves the oil control issues for throttled compressors for all you turbocharging guys who are having oil issues. It is sheduled to be presented at the World Congress in April 16-19 2007 in Detroit. It is specific to the GT12 but is applicable to all applicaitons. It also goes through some other aspects assocaited with turbocharger water cooling, control and some other stuff

2007-01-1562
http://eprints.infodiv.unimelb.edu.au/archive/00002816/02/2007-01-1562.pdf
Highly Turbocharging a Flow Restricted Two Cylinder Small Engine - Turbocharger Development

Regards
William Attard
University of Melbourne, Australia

[Ian M]

Thanks man. Haven't had a chance to take a look at it yet, but wanted to thank you for passing on the knowledge.

[Chuck Dean]

I imagine you got the sealing rings from Garrett?

[civicsit]

William-

Good paper. Looks like you took a lot of time in fixing the oil leak problem. I might try to see if I can implement it on our next car.

Thanks

[BryanH]

Taken from Attards Paper, "The engine was installed into successive MUR Motorsport vehicles in 2003 and 2004. The first vehicle achieved the second fastest lap time at the 2003 Australasian competition." ???????????
Not at the event I went to

[Pedrot16]

congratulations, very good work and thanks for sharing.

That seals are from garret?

[Krautsalat]

if you would be pedantic, this modification violates the rule that all air entering the engine has to pass through the restrictor http://fsae.com/groupee_common/emoticons/icon_wink.gif

Krautsalat

[Pete M]

Very interesting idea. It's technically in violation of the rules, but i doubt any tech inspector would be pedantic enough to pull you up on it.

We tend to shy away from extensive modifications to our turbos these days though, because it's one less thing the team has to do every year. There are simpler ways to solve the oil problem. We use a variation of the pressure equalisation idea UTA came up with years ago. Works great.

[powered by wattard]

There is no violation of the rules here as the vent is between 2 seals. The intake system is sealed, sealed as good as the piston ring during induction anyway or in the same way as if the stardard GT12 was installed with oil drain to the sump, with the sump vented. Any ring leakage is identical to piston ring leakage during induction, with a vacuum in the cylinder as the piston goes down towards BDC. If the vent was on the other side of the seal directly seeing MAP, then I would agree with you. The vent also creates a pressure balance across rhe ring seal.

[aniLD]

William definitely has a point there guys; it's in no way violating the rules to any further than what the standard gt12 does. It totally solves the oil issue with a clever approach that's different to what has been done before in SAE. Then again so was the rest of the engine.
From what I remember Garret was very interested in it as they couldn't solve the problem themselves.

[Pete M]

Well, i did say "technically". If the rings sealed perfectly, then there'd be no need for the vent to start with, and none of us would be having leakage issues. As you say, technically the way the pistons are sealed is illegal too, as air that hasn't been through the restrictor can end up in the cylinder...

Anyway, enough pedantry. It's obviously within the intent of the rule. I wasn't seriously suggesting it as a criticism, and i doubt Krautsalat was either.

The only reason i posted was that i know there are a lot of teams trying to get turbos working, and while your method is probably the ideal solution, it's not the only practical one. You'd want to pretty seriously know what you're doing before you attempt it and it'd probably be outside the ability of a lot of teams.

[Garlic]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by BryanH:
Taken from Attards Paper, "The engine was installed into successive MUR Motorsport vehicles in 2003 and 2004. The first vehicle achieved the second fastest lap time at the 2003 Australasian competition." ???????????
Not at the event I went to </div></BLOCKQUOTE>

I agree. Normally FSAE individual times are not tracked, so hard to prove it.

BUT, at this event they were. And here they are: (note Title says 2004 but date is 2003 and times are of teams present that year)

Index (http://www.racetime.com.au/?event=f0302)
Autocross (http://www.racetime.com.au/?event=f0302&e=q03&view=fastest)
First Endurance (http://www.racetime.com.au/?event=f0302&e=q04&view=fastest)
Second Endurance (http://www.racetime.com.au/?event=f0302&e=q05&view=fastest)

My combined endurance times put them 9th of 17 cars.

This should not undermine the technical quality of the paper, which is excellent. And God knows that the engine can't put you at the top of the time charts alone. But one has to wonder why it was stated.

[powered by wattard]

I suppose people responding to my paper is a good thing. It means they are actually reading it.

My apologies for the incorrect statement. It was a big weekend. I was sure we set a 46.8 which would have put us second in the first enduro. We posted a 47.8 which is a little further behind, my apologies. Garlic, thanks for the link to sae times. It might come it handy for future refernce. I'll remove the comment from the paper, as it was only quoted in this particular SAE paper out of the 5 other papers which I have published. I have no reason to intentionally lie about it as the event was several years ago and there is nothing to be gained out of it. My mistake. Anyway, I have been recognised for my accomplishments in other ways

http://www.sae.org/servlets/pressRoom?OBJECT_TYPE=Press...lease&RELEASE_ID=518 (http://www.sae.org/servlets/pressRoom?OBJECT_TYPE=PressReleases&PAGE=showRelease&RELEASE_ID=518)


Guys, the intent of posting this paper was to share some of the knowledge I gained during FSAE turbocharger development with the current crop of students who are trying to implement tubocharging. I hope that it is useful to you doods out there who will actually use it

If anyone has any more comments about any of my other papers, I am happy to listen. I will always be happy to listen about any discussion concenring SAE. It is such a good learning experience for young engineers. However, just remember it is much easier to critise than to try and contribute to helping the future breed of students.

Regards

William Attard

[ad]

Congratulations Will!

Thats a great achievement for you.

There is alot of critiscism around on the forum, and you would think that your help here would be praised considering the majority of turbo teams still have yet to address this (oiling) issue completely.

Do you use the carbon seal on the GT12 with your venting arrangement?

[VFR750R]

Will, I recently read your paper on turbocharging. I had a few questions.

The constant pressure turbocharging is not used often in motorsport. I'm curious into whether you did any work with different primary lengths to the plenum or collecting the two cylinders before the plenum?

Second, did you guys do any simulation with an engine size closer to the 610 limit? Friction and wieght would be extremely close with a similar design, and avg power output would likely overcome the small increase in peak power you were expecting.
Transiently, the larger engine would always win.


Did you guys also look at an even firing engine? I've found mentions of total balance of the crank but not a breakdown of the decision to run a 180 crank.
Interestingly, but off topic, Honda's old V4 750 racers had 360deg cranks for racing. I believe only the RC30's and RC45's got 360 cranks from the factory, although the smaller 400cc versions may have also. The street VFR750's got 180deg cranks.

[fart can]

Thanks for the excellent paper Will.

Did you get the oil seals from Garrett or another vendor?

Thanks

[310Turbo]

Hey guys, lots of information and questions; good stuff!

I haven't had a chance to go through Will's paper in detail but I had a chance to look through it briefly a little while ago. It's an interesting idea and something that's been tried in the past on other applications.

I've had some teams request this particular conversion and I'd like to address as large an audience as I can with one posting so I figured I would do it in this thread, pardon the interruption.

Please note that the GT12 and GT15V turbos offered by Honeywell are mass produced units and that requesting specially machined components is a virtual impossibility when we are speaking of the volumes we use for FSAE support. We cannot have center housings modified at the supplier level; simply too costly and it poses potential contamination risk to our production line. Ordering spare parts such as center housings, turbine wheel assemblies, bearings, piston rings, etc is not feasible either.

For a very short period we attempted carbon seal conversions; our attempt showed us that it was prohibitively expensive for us to continue doing these. The conversions themselves cost more than the turbo, nearly tripling our hardware budget. To continue these conversions meant we would have to reduce our sponsored teams by at least half, if not more. We would like to see an increase in forced induction use at these competitions and limiting our sponsorship to such low numbers would hurt this effort. I'm sure most teams remember the huge task it was to engineer a reliable n/a system let alone an FI one! With that in mind, we want to keep our sponsorhip numbers higher knowing that not all teams who are sponsored will be able to field a turbo car during that year.

We cannot offer reassembly or rebalance services if you choose to modify your turbo. There are several turbocharger rebuild companies who can offer this service, a quick search on the internet turns up several options.

We offer one replacement turbo should your unit fail prior to competition; please note that attempting this conversion would void our hardware replacement offer. We can't give every team a free pass to "try" this conversion with the fallback that if it gets mucked up we'll simply send them a fresh one. This would place a strain on our inventory and consume units that a team might need just prior to competition. It's not unheard of for us to overnight turbos to Detroit http://fsae.com/groupee_common/emoticons/icon_wink.gif

We understand that the turbos as they come may not fit within the confines of your powertrain layout and that re-orientation of housings may be necessary. No problem with this and this does not void our hardware replacement offer.

Technical support still stands regardless of whether or not you attempt this seal conversion. While we encourage every team to continually push the engineering envelope, we cannot officially support any modification of these turbos (short of housing re-orientation).

I hope this answers most everyone's questions regarding our position with respect to this seal conversion. My hat's off to Will for doing this and for sharing his research with the community!

If there are any other questions, feel free to contact me via email; Cam.Thai *at* Honeywell.com

Best regards,
Cam

[PatClarke]

Hi all.
A word to the wise,
Always remember that before you consider following Will's advice, just run it past the Rules Committee.
The competition is not the place where you need to get involved in a deep and meaningful debate over legality.

Regards
Pat

[Bill Kunst]

Coule you not just run the turbo seal vent to the restrictor before the throttle body to solve this "issue"?

[Kirk Feldkamp]

Come on guys... if more teams give positive feedback to the Rules Committee about the rule change proposal, then nobody would be having to go to these rediculous lengths to run a turbo. The amount of time it would take to write a quick letter is far, far, FAR less than it's going to take you to procure and develop a new seal design. It isn't magic and I'm sure it works great (we've had similar pressure-fed seals for many years)... but what's the point? What are you really going to learn by copying what William has already done? The whole point of using a turbo in FSAE is to learn how to integrate it into a system and to spend the time developing that system. Rather than reinventing the wheel, your time is MUCH better spent convincing Michael Royce that the rules need to be fixed!

-Kirk

[VFR750R]

whatever...that won't fix much this year

[Bill Kunst]

VFR,
I am not slamming you when I say this, just that attitude. Sure it won't fix anything this year, but how about for next year. I would have to agree that if you were to move the tb within mere inches (2-3) of the input of the turbo with a max volume of (x)cc's, there would be no advantage other then the design time that Will has spent and procured for the whole entire Formula SAE world. What other reason would they not want to switch the rules for?

[Kirk Feldkamp]

VFR750R,

Agreed. Then again, there will never be a cost effective fix unless teams take the time to make the rule change into reality. I've been doing FSAE support here at Honeywell for a couple years now, and the oil issue is probably 90% of what teams struggle with. There is no simple solution that seems to work for everyone. Is the problem impossible? Absolutely not. We have double (and even triple) piston ring seals on certain types of turbochargers for just this reason. It just happens that the high production turbos that match well to FSAE requirements have single piston rings.

I'm not sure how many people on this forum have actually worked at a company as large as Honeywell (I think we made close to 8 million turbos worldwide last year), but supporting a super small number turbos like we do for FSAE suddenly becomes very expensive as soon as anything "non-standard" comes into the picture. Cam's description of the cost of doing the carbon seals is a perfect example. Even getting extra center housings for teams to perform their own modifications on would be a relatively major undertaking.

-Kirk

[VFR750R]

Man, I was rolling on the floor laughing when I wrote that cause I knew what the response was going to be. Everybody here knows my stance on the rule change and we got 3 or 4 threads on it already. You guys make very valid points, but there is no point in hijacking this one too.

[Kirk Feldkamp]

Hijacked! (sort of)

Ya ya, you got me. http://fsae.com/groupee_common/emoticons/icon_redface.gif

I was trying (again) to motivate people to act. The situation is never going to change if teams don't get off their butts and do something about it.

-Kirk

[Pete M]

Would it make our lives easier if we had the throttle in a different location? Probably. Would it allow other teams to short-cut a lot of the development we've already done? Certainly. It may sound selfish, but i think the reason a lot of the present turbo teams aren't very supportive of the rules change is that they've already invested significant time in getting around the problems caused by that rule. We're in the process of designing our 4th turbo car now, and if the rules were to change, much of the development of the last 3 years will be made moot. Would teams that have spent a lot of man-hours optimising the restrictor support its removal? Sure, it'd mean more power for them too, but they'd lose a competitive advantage.

Wollongong have run turbos that have been modified in various ways before (including carbon seals) but as of last year we've developed a system that lets us run these turbos without any modifications. This makes it a hell of a lot easier to get replacements and saves a lot of time doing the same modifications year after year. There's nothing massively tricky about our solution, but it took a fair bit of time to develop and quite a few test days with plumes of white smoke trailing the car.

The present location of the throttle also means that turbo teams have to compromise a lot to keep response good. A decent sized intercooler adds intake volume and hurts response. This encourages more innovative solutions such as clever use of E85 (something we can't do at present as it's not a fuel at FSAE-A). I think if we were allowed to put the throttle in a more standard position, we'd just start seeing a large fraction of the FSAE field migrate to very conventional turbo setups. I can understand why Garrett would want this but i'm not sure that's what's best for the comp.

With the rules at present we see a very wide variety of powerplants all fairly competitive with each other. The top two dynamic event cars in FSAE West 06 were a supercharged single and a turbocharged 600. Autocross was won by an NA 600 and an NA single came 2nd overall (and did rather well at the comp immediately previous). It is not obvious which is the "best" approach to FSAE and imho that's the way it should be.

Peter

[begreer]

Where did you aquire the additional seals?

[powered by wattard]

For all you guys planning to attend the SAE World Congress (April 16-19 2007)which is just a few weeks away, this paper is scheduled to be presented on Thursday the 19th at 1.30pm if anybody has any questions or would just like a general chat. See you in Detroit

Regards

William Attard