X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 82 [XXX] (38%) BODY: contains an image tag with CID (31%) URL: contains host with port number (31%) RECEIVED: IP not found on home country list Return-Path: Received: from mail01.syd.optusnet.com.au ([211.29.132.182] verified) by logan.com (CommuniGate Pro SMTP 5.1.8) with ESMTPS id 2042499 for flyrotary@lancaironline.net; Sun, 13 May 2007 18:49:53 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.182; envelope-from=lendich@optusnet.com.au Received: from george (d220-236-205-176.dsl.nsw.optusnet.com.au [220.236.205.176]) by mail01.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id l4DMn7bi032687 for ; Mon, 14 May 2007 08:49:08 +1000 Message-ID: <006301c795b0$ed18d9c0$b0cdecdc@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: EC2 smoke question Date: Mon, 14 May 2007 08:49:11 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0060_01C79604.BDC83A40" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0060_01C79604.BDC83A40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Thanks again Lynn- I'm taking it all in!! George ( down under) Lynn Your saying what I want to hear P-port, high intake velocity = (smaller diameter tubes - I thinking about 1.6") and a after = considering Tracy's set-up and Talking to Ian Beadle ( Western = Australia) I'm also leaning toward the shorter inlet tube length. Of course nothing beats proof of testing. Well, there are some things to think about here. The shortest length = that gives you one complete cycle of inlet reversion at the peak power = RPM is all that is required. The idea that the inlet tract length has a = big affect on power output has been proven time and again. For the math = impaired, like me, it is quicker to build the example and make the = changes to peak it up on a dyno. But others have gone before to break = this ground, so copy from them, or from a known good performer.=20 How is it that different lengths could work for the same situation? = The exact length may not be as long as you would think. But it may = present other difficulties that occur at lower RPM than peak power. So, = at a peak of say, 6,000 RPM a standing wave of fuel mist may be just = inside the bell at the inlet end of the runner. Where would that ball of = fuel mist be at 5,500 RPM where we want to cruise the engine? Well, it = would be just outside the bell shape in the air filter or in the log = manifold. In the event of a misfire, at top speed, this would be = ingested with no problem, but at cruise there might be 4 such balls = floating in the air filter, and a misfire would be a life altering = experience. . Another vote for both injectors closer to the engine. The = fuel mist balls are a physical manifestation of the reversion wave = rarifying. Marking how long the completed reversion column is at that = RPM. Often seen on the dyno when running with no air filter=20 So maybe, doubling the ideal inlet length would be a good idea. The = first, fourth and sixteenth harmonic of any frequency should work nearly = as well so twice the length should be fine. Plus the more mass in the = air column should make the mid range come up a bit stronger. The effect = on top power will be to reduce it somewhat. So the best performance for = doubled the length would be at=20 3,000 RPM where it adds to the mid range and does not seem to fit the = bill at all. But the anything will work rules apply and the loss at the = top may not affect 5,500 RPM and now may help it. =20 Another gag to shorten a system without much of a penalty is use a = tapered runner. Bigger carb or TB on the end and increasing velocity as = the flow enters the engine. About the same mass, same or better velocity = at the port face, less dependant on harmonics, less drag from a smaller = diameter it's whole length.=20 Speaking to Ian (he's into electronics) he suggested ( If I = understood him correctly) that the sine wave of the exhaust pulses are = shorter as the RPM goes higher (makes sense), so the intake length needs = to be shorter. I was always under the impression that the shorter manifold was for = torque and the longer for HP - but as they are inextricably linked = (HP=3DTxRPM/5252), what real difference is there, if any, in relation to = aviation needs. Perhaps pulling a few more RPM?? Mind you I'm still working on the single and to get a healthy HP out = of it. I'm hoping to achieve 125HP and maybe as much as 150 hp. You should get at least 110 HP at 6,000 RPM without much strain. More = for a Pport. A bit of boost and the sky is the limit. The single rotor = with no rocking couple should do just fine, and be very smooth at higher = RPM.=20 I'm still debating the simplicity of a carby V fuel injection, after = riding the new bike around Australia I now understand the benefits of FI = in relation to economy. The injection wins both ends of the argument, if you don't count cost. BTW I was hoping you would take a stab in the dark and say 6" to 8" = would be sufficient for the intake tube. Guessing 20" of constant diameter tube. Or, with a nice taper maybe = 12" to 16".=20 After thinking about two TB's (as you suggested), it adds another = variable to the equation, I've got all sorts of things to consider. On another point, have you used the steel Bellhousings on the rotary = and are they very heavy!?=20 I have never heard of or seen a steel bellhousing for a rotary? George ( down under) Lynn E. Hanover -------------------------------------------------------------------------= ----- See what's free at AOL.com.=20 -------------------------------------------------------------------------= ----- -------------------------------------------------------------------------= ----- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_0060_01C79604.BDC83A40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
 Thanks again Lynn- I'm taking it all = in!!
George ( down under)
 
Lynn
Your=20 saying what I want to hear P-port, high intake velocity (smaller = diameter=20 tubes - I thinking  about 1.6") and a after considering Tracy's = set-up=20 and Talking to Ian Beadle ( Western Australia) I'm also leaning = toward the=20 shorter inlet tube length.
Of course nothing beats proof of=20 testing.
Well, there are some things to think about here. The shortest = length that=20 gives you one complete cycle of inlet reversion at the peak power RPM = is all=20 that is required. The idea that the inlet tract length has a big = affect on=20 power output has been proven time and again. For the math impaired, = like me,=20 it is quicker to build the example and make the changes to peak it up = on a=20 dyno. But others have gone before to break this ground, so copy from = them, or=20 from a known good performer.
 
How is it that different lengths could work for the same = situation? The=20 exact length may not be as long as you would think. But it may present = other=20 difficulties that occur at lower RPM than peak power. So, at a peak of = say,=20 6,000 RPM a standing wave of fuel mist may be just inside the bell at = the=20 inlet end of the runner. Where would that ball of fuel mist be at = 5,500 RPM=20 where we want to cruise the engine? Well, it would be just outside the = bell=20 shape in the air filter or in the log manifold. In the event of a = misfire, at=20 top speed, this would be ingested with no problem, but at cruise there = might=20 be 4 such balls floating in the air filter, and a misfire would be a = life=20 altering experience. . Another vote for both injectors closer to the = engine.=20 The fuel mist balls are a physical manifestation of the reversion wave = rarifying. Marking how long the completed reversion column is at that = RPM.=20 Often seen on the dyno when running with no air filter 
 
So maybe, doubling the ideal inlet length would be a good idea. = The=20 first, fourth and sixteenth harmonic of any frequency should work = nearly as=20 well so twice the length should be fine. Plus the more mass in the air = column=20 should make the mid range come up a bit stronger. The effect on top = power will=20 be to reduce it somewhat. So the best performance for doubled the = length would=20 be at
3,000 RPM where it adds to the mid range and does not seem to fit = the=20 bill at all. But the anything will work rules apply and the loss at = the top=20 may not affect 5,500 RPM and now may help it.  
 
Another gag to shorten a system without much of a penalty is use = a=20 tapered runner. Bigger carb or TB on the end and increasing velocity = as the=20 flow enters the engine. About the same mass, same or better velocity = at the=20 port face, less dependant on harmonics, less drag from a smaller = diameter it's=20 whole length.
 
Speaking to Ian (he's into electronics) he suggested ( If I = understood=20 him correctly) that the sine wave of the exhaust pulses are shorter = as the=20 RPM goes higher (makes sense), so the intake length needs to be=20 shorter.
I was always under the impression that the shorter = manifold was=20 for torque and the longer for HP - but as they are=20 inextricably linked (HP=3DTxRPM/5252), what real difference is = there, if=20 any, in relation to aviation needs. Perhaps pulling a few more = RPM??
Mind you I'm still working on the single and to get a healthy = HP out of=20 it. I'm hoping to achieve 125HP and maybe as much as 150=20 hp.
You should get at least 110 HP at 6,000 RPM without much strain. = More for=20 a Pport. A bit of boost and the sky is the limit. The single rotor = with no=20 rocking couple should do just fine, and be very smooth at higher RPM. =
I'm still debating the simplicity of a carby V fuel injection, = after=20 riding the new bike around Australia I now understand the benefits = of FI in=20 relation to economy.
The injection wins both ends of the argument, if you don't count=20 cost.
BTW I was hoping you would take a stab in the dark and say 6" = to 8"=20 would be sufficient for the intake = tube.
Guessing 20" of constant diameter tube. Or, with a nice taper = maybe 12"=20 to 16".
After thinking about two TB's (as you suggested), it adds = another=20 variable to the equation, I've got all sorts of things to = consider.
On another point, have you used the steel Bellhousings on the = rotary=20 and are they very heavy!? 
I have never heard of or seen a steel bellhousing for a = rotary?
George ( down under)
 
Lynn E. = Hanover
 



See what's free at AOL.com.=20

--
Homepage:  http://www.flyrotary.com/
Archive and=20 UnSub:  =20 = http://mail.lancaironline.net:81/lists/flyrotary/List.html
------=_NextPart_000_0060_01C79604.BDC83A40--