Return-Path: Received: from ms-smtp-03.southeast.rr.com ([24.93.67.84] verified) by logan.com (CommuniGate Pro SMTP 4.1.4) with ESMTP id 2603243 for flyrotary@lancaironline.net; Thu, 25 Sep 2003 09:29:01 -0400 Received: from o7y6b5 (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-03.southeast.rr.com (8.12.5/8.12.2) with SMTP id h8PDQc4S005434 for ; Thu, 25 Sep 2003 09:26:41 -0400 (EDT) Message-ID: <00b101c38368$b1046ac0$1702a8c0@WorkGroup> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: DIE the short Answer Date: Thu, 25 Sep 2003 09:26:56 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00AE_01C38347.2995B6A0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 This is a multi-part message in MIME format. ------=_NextPart_000_00AE_01C38347.2995B6A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message Morning Ed. I admit that I've only been skimming over the EDDIE = messages, so this may be a dumb question. Does this effect raise the = pressure in the intake runners in such a way that the EC-2 will see it = via the MAP sensor? If not, it would seem that adjusting the runners in = and out of the effect will throw off the mixture. I'm sure you've = thought of this, so it's probably a silly question. =20 Rusty (ordering a stock RV-3 cowl today) Morning, Rusty. It is unlikely that the EC-2 would respond to this = pressure increase given where it occurs and its short duration. The big = pressure increase effect is fairly localized in the runners. Remember = this is a pulse of energy not a slug of air. While unobstructed = traveling down the tube, very little of this energy is converted to = pressure, However, when it reaches the end of the runner, the kinetic = energy of the Mach 1 wave is converted to dynamic pressure. These = pulses (Finite-Amplitude Waves) have been measured as creating = overpressure ratios of 1.5 - 2.0 that is from 21-30 PSI absolute. After = seeing what the exhaust FAW did to my stainless steel fish tails on my = exhaust (fragmented them in a few minutes, just fatiqued the metal to = the point that chucks fell out), I am a believer. Incredible strong, = but unfortuantely - just as incredible short in duration {:>) However, getting to the point of your question - not to worry. It has = no significant effect on the Air/Fuel mixture. It is not as if this = energy wave is pushing a fresh batch of air into the equation (without = compensating with more fuel ) and therefore upsetting the A/F ratio. = Rather, view it as simple a mechansim for ensuring that more of the = air/fuel mixture already there at the intake port gets into the chamber = each time it opens. Hope this helps. I see you have a new cowl on order. I was wondering exactly what = configuration for cooling do you have in mind? I presume the two = evaporator core approach is just not configuration compatible with all = you need to put under the cowling. One thing, my brief experiment with = reducing the inlet size by 33% tells me, is that contouring the flow = from inlet to radiator does indeed make a significant difference in = cooling performance. =20 Hang in there. I know about the harassment you take from the Lycoming = guys. But who really cares, they pay their outlandish prices for 1932 = technology and think they have a great deal. Nothing wrong with a = Lycoming as an aircraft engine except its price, reliability, price, = maintance cost, price, etc.. =20 I now have more hours behind a rotary than a Lycoming (about 400 total = with 220 behind the Rotary), which I consider a milestone {:>) Ed Anderson ------=_NextPart_000_00AE_01C38347.2995B6A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
 Morning Ed.  I admit that I've only been skimming = over the=20 EDDIE messages, so this may be a dumb question.  Does this effect = raise the=20 pressure in the intake runners in such a way that the EC-2 will see it = via the=20 MAP sensor?  If not, it would seem that adjusting the runners in = and out of=20 the effect will throw off the mixture.  I'm sure you've thought of = this, so=20 it's probably a silly question. 
 
Rusty = (ordering a=20 stock RV-3 cowl today)
 
Morning, Rusty.   It = is unlikely=20 that the EC-2 would respond to this pressure increase given where it = occurs=20 and its short duration.  The big pressure = increase effect is=20 fairly localized in the runners.  Remember this is a pulse of = energy not=20 a slug of air.  While unobstructed traveling down the tube, = very=20 little of this energy is converted to pressure, However, when it = reaches the=20 end of the runner, the kinetic energy of the Mach 1 wave is = converted to=20 dynamic pressure.  These pulses (Finite-Amplitude Waves) have = been=20 measured as creating overpressure ratios of 1.5 - 2.0 that is from = 21-30 PSI=20 absolute.  After seeing what the exhaust FAW did to my stainless = steel=20 fish tails on my exhaust (fragmented them in a few minutes, just = fatiqued the=20 metal to the point that chucks fell out), I am a believer.  = Incredible=20 strong, but unfortuantely - just as incredible short in duration=20 {:>)
 
However, getting to the point = of your=20 question - not to worry.  It has no significant effect on the = Air/Fuel=20 mixture.  It is not as if this energy wave is pushing a fresh = batch of=20 air into the equation (without compensating with more fuel ) and = therefore=20 upsetting the A/F ratio.  Rather, view it as simple a mechansim = for=20 ensuring that more of the air/fuel mixture already there at the = intake=20 port gets into the chamber each time it = opens.
 
Hope this = helps.
 
I see you have a new cowl on = order.  I=20 was wondering exactly what configuration for cooling do you have in=20 mind?  I presume the two evaporator core approach is just not=20 configuration compatible with all you need to put under the = cowling.  One=20 thing, my brief experiment with reducing the inlet size by 33% tells = me, is=20 that contouring the flow from inlet to radiator does indeed make a = significant=20 difference in cooling performance. 
 
Hang in there.  I know = about the=20 harassment you take from the Lycoming guys.  But who really = cares, they=20 pay their outlandish prices for 1932 technology and think they have a = great=20 deal. Nothing wrong with a Lycoming as an aircraft engine except = its=20 price, reliability, price, maintance cost, price, etc.. =20
 
I now have more hours behind a = rotary than=20 a Lycoming (about 400 total with 220 behind the Rotary), which I = consider a=20 milestone {:>)
 
Ed Anderson



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