Mailing List flyrotary@lancaironline.net Message #4235
From: Jim Sower <canarder@frontiernet.net>
Subject: Re: [FlyRotary] DIE Summary
Date: Wed, 05 Nov 2003 14:42:48 -0600
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Ed,
Great job.  Wish I'd been more alert at the forum at Tracy's.  Anyway, I just
had another brain fart.
The time it takes the FAW to get from one port to another is a function of
Temp.  The time you WANT it to take is a function of RPM.  You would like to
have DIE at several temperatures and RPMs but since you can't control the temp,
the RPM will be a function of whatever temp you end up with that day.  What if
you had two each primary and secondary injectors - one at the top of the runner
and one at the flange or in the block or wherever (where it is now).  If you
could bias the fuel injected between the two injectors, the heat of vaporization
of the fuel would have a big impact on charge temp and might very well make
intake temp (and therefore Tr) controllable.

I don't know how big an engineering challenge it would be to vary the fuel
delivered to "upper" and "lower" injectors so as to control the intake temps,
but perhaps it could be done with fuel pressure.  It would be arguably more
reliable to do it electronically by biasing the pulse width of the injection
event between the injectors, but any way you do it, controlling intake temp
might turn out easier to accomplish than modulating the runner length.

Some brain farts are just brain farts .... Jim S.

Ed Anderson wrote:

> Ok, Folks
>
>     I have finally completed the "script" to go with the DIE presentation
> given at Shady Bend.  For those of you, who had the "misfortunate" to have
> to sit through it, you will find that it is not exactly how the actual
> presentation went (for several reasons {:>)).  Since I never seem able to
> exactly follow a script (even when I write one), no presentation I give is
> ever quite the same twice running in any case.  But, I believe I have
> cleaned the flow up a bit which might make it easier to follow.
>
> The DIE related products include:
>
> PDF of the Slides used in the Shady Bend presentation 1.4 Meg
> PDF of the Formal (sort of)  Mathematical derivation of the equations 225K
> PDF of a short summary of the equations Attached to this e mail 95K
> Excel DIE Spreadsheet for doing your own DIE calculations. 250K
>
>    Tracy and Laura Crook indicated they would post this to their web site at
> some point.  As most of you realize, Laura, is the stuckee for all the web
> page work on the Real World Solutions web site - and in addition to taking
> care of  the RWS business, answering e mails, running the Florida RV events
> schedule and coordinating such, she works a full week in Atlanta and runs a
> home - makes me tired just listing her work load.  So, I would imagine that
> getting the DIE stuff posted to the web page is somewhere down her priority
> list.  In other words, patience is called for.
>
>     However, for those of you interested, I have attached a very brief
> summary of the DIE equation derivation.  Its only two pages, with some
> graphs attached and is probably not that easy to follow without the expanded
> step by step derivation process shown in the full up presentation.
>  Hopefully, it will keep those interested in the DIE occupied until the
> full-up presentation is on the RWS web site {:>).
>
> Best Regards
>
> Ed
>
> Ed Anderson
> RV-6A N494BW Rotary Powered
> Matthews, NC
> eanderson@carolina.rr.com
>
>   ----------------------------------------------------------------
>                            Name: DIE Summary 2003.PDF
>    DIE Summary 2003.PDF    Type: Acrobat (application/pdf)
>                        Encoding: base64
>
>   ----------------------------------------------------------------
> >>  Homepage:  http://www.flyrotary.com/
> >>  Archive:   http://lancaironline.net/lists/flyrotary/List.html

--
Jim Sower
Crossville, TN; Chapter 5
Long-EZ N83RT, Velocity N4095T


Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster