X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 938045 for flyrotary@lancaironline.net; Mon, 09 May 2005 18:21:52 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-189-178.carolina.res.rr.com [24.74.189.178]) by ms-smtp-04-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j49ML4L5025948 for ; Mon, 9 May 2005 18:21:05 -0400 (EDT) Message-ID: <000601c554e5$64a7f520$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: center rotor OFF Date: Mon, 9 May 2005 18:21:05 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0003_01C554C3.DD583AB0" 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-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0003_01C554C3.DD583AB0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Seems to me that the acoustical wave generated by the canceling device = would have to be of a magnitude similar to the amplitude of the nose = wave you are trying to cancel - that's like 125+ db!!!. Plus its = speaker would probably need to be able to withstand a great deal of heat = surely in the 100s of degrees F. The theory has been around for years, = but the practically of the idea - at least for engine exhaust for = aircraft has eluded me for certain. But who knows? if its possible then = its just technology that is needed to meet the conditions of the = environment (very harsh and hostile). Ed A ----- Original Message -----=20 From: David Staten=20 To: Rotary motors in aircraft=20 Sent: Monday, May 09, 2005 6:04 PM Subject: [FlyRotary] Re: center rotor OFF Ok... so whats the solution for all the people who are nearby when you = fire the engine up? Your neighbors, etc? =20 Dave Mark R Steitle wrote: Here is the answer to the muffler problem. Active Noise Control. = No big, heavy, draggy muffler needed. =20 .Active Noise Control is unique to this vehicle. Active Noise = Control (ANC) uses sound waves generated from the audio speakers to = cancel out any booming noise from the powertrain. The ANC controller = uses a microphone to detect any noise and then generates a signal 180 = degrees out of phase to cancel out the original noise.=20 Mark S. -------------------------------------------------------------------------= --- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Russell Duffy Sent: Monday, May 09, 2005 2:24 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: center rotor OFF I'm thinking this would not be a good plan. For the piston engines = you referred to, I bet they have a way to control the valves with = solenoids so the deactivated pistons aren't producing compression.=20 Actually they do have compression. No fuel or fire.=20 Bill Jepson=20 OK, make me look it up :-) Apparently, they stop the valves from = opening, rather than leaving them open. I couldn't find anything that = gave details of exactly what point in the sequence they stop the valves, = so the cylinder could either be full of air (silly and wasteful of = power), empty of air (would cause vacuum that would be as bad as the = compression force), or perhaps somewhere in between. =20 Here's the best article I found, though with annoying ads. Don't = forget about those active controlled engine mounts to smooth out the 3 = cylinder operation in economy mode. Just boggles the mind what they'll = do to make improvements in economy.=20 http://www.canadiandriver.com/articles/jk/041014.htm Cheers, Rusty (Great Plains VW 2180 running, and for sale) >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_0003_01C554C3.DD583AB0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Seems to me that the acoustical wave = generated by=20 the canceling device would have to be of a magnitude similar to the = amplitude of=20 the nose wave you are trying to cancel - that's like 125+ db!!!. = Plus its=20 speaker would probably need to be able to withstand a great deal of heat = surely=20 in the 100s of degrees F. The theory has been around for years, = but the=20 practically of the idea - at least for engine exhaust for aircraft has = eluded me=20 for certain. But who knows? if its possible then its just technology = that is=20 needed to meet the conditions of the environment (very harsh and=20 hostile).

Ed A

----- Original Message -----
From:=20 David=20 Staten
To: Rotary motors in = aircraft

Sent: Monday, May 09, 2005 6:04 = PM

Subject: [FlyRotary] Re: center = rotor=20 OFF

Ok... so whats the solution for all the people who are = nearby=20 when you fire the engine up? Your neighbors,=20 etc?

Dave

Mark R Steitle wrote:

Here is = the answer=20 to the muffler problem. Active Noise Control. No big, = heavy,=20 draggy muffler needed.

<snip = from=20 =93Canadian Driver=94 article>

=85Active Noise=20 Control is unique to this vehicle. Active Noise Control (ANC) uses = sound=20 waves generated from the audio speakers to cancel out any booming = noise from=20 the powertrain. The ANC controller uses a microphone to detect any = noise and=20 then generates a signal 180 degrees out of phase to cancel out the = original=20 noise.

<snip>

Mark=20 S.

From:=20 Rotary motors in aircraft [mailto:flyrotary@lancaironlin= e.net]=20 On Behalf Of Russell = Duffy
Sent: = Monday, May 09,=20 2005 2:24 PM
To: = Rotary=20 motors in aircraft
Subject:=20 [FlyRotary] Re: center rotor OFF

I'm = thinking this=20 would not be a good plan. For the piston engines you referred = to, I=20 bet they have a way to control the valves with solenoids so the = deactivated=20 pistons aren't producing compression.

Actually they do have=20 compression. No fuel or fire.

Bill = Jepson

OK, make = me look it=20 up :-) Apparently, they stop the valves from = opening, rather than=20 leaving them open. I couldn't find anything that gave details = of=20 exactly what point in the sequence they stop the valves, so the = cylinder=20 could either be full of air (silly and wasteful of power), empty of = air=20 (would cause vacuum that would be as bad as the compression force), = or=20 perhaps somewhere in between.

Here's the = best=20 article I found, though with annoying ads. Don't forget = about=20 those active controlled engine mounts to smooth out the 3 = cylinder=20 operation in economy mode. Just boggles the mind what they'll = do to=20 make improvements in economy.

http://www.= canadiandriver.com/articles/jk/041014.htm

Cheers,

Rusty = (Great Plains=20 VW 2180 running, and for sale)

>> Homepage: http://www.flyrotary.com/ >> Archive: = http://lancaironline.net/lists/flyrotary/List.html

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