X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from qw-out-2122.google.com ([74.125.92.27] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3844506 for flyrotary@lancaironline.net; Thu, 10 Sep 2009 11:43:15 -0400 Received-SPF: pass receiver=logan.com; client-ip=74.125.92.27; envelope-from=rwstracy@gmail.com Received: by qw-out-2122.google.com with SMTP id 3so72828qwe.25 for ; Thu, 10 Sep 2009 08:42:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=B+Ta6exIxeLh96b8g153UNOb6JGI/5mzwVadg8qOsfs=; b=TMI12rULeg/3nfC6CLXhjwltXcnxuL6riJAh2uBSRcj0EJvTqV0UTJD4LAmouSSGoQ kdnPln6oaMBxFx6kwDmzzObqhfS5vZFs0Ip8CMGq2/zgXPPdgMPkeprA/t7Ymvq2fHLv 8Udc9O69+RyrgIR9TNL9vnY3Q7SDpEgSFKIic= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=o3idS6Vrr9VHdffe1rPKhMQECatJ2/6YwTZRIgQe7WIFN8z0T8msHqrtKC08ZplMyp cbZUntuV1VG9vXgfnKlLwgu9tNaPMV0qnp2pJZW7+Wr0EJH6r3PAVZ65zBKBbC94xapc 4ETXk2pVqbAlqIIlxwwnvgEQ5xGNXoRA0HVJo= MIME-Version: 1.0 Sender: rwstracy@gmail.com Received: by 10.224.78.221 with SMTP id m29mr1507958qak.20.1252597360462; Thu, 10 Sep 2009 08:42:40 -0700 (PDT) In-Reply-To: <1b4b137c0909100631p40c49a8ife378cb7628b2431@mail.gmail.com> References: <1b4b137c0909100631p40c49a8ife378cb7628b2431@mail.gmail.com> Date: Thu, 10 Sep 2009 11:42:40 -0400 X-Google-Sender-Auth: 57e65ab122b31fa7 Message-ID: <1b4b137c0909100842r6a09b98amb0b782e6001ee94e@mail.gmail.com> Subject: Re: [FlyRotary] cooling plumbing design [right?, right?, right? :-) ] From: Tracy Crook To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=00c09f9c99c6b7a39b04733b0c9e --00c09f9c99c6b7a39b04733b0c9e Content-Type: text/plain; charset=ISO-8859-1 Re-reading Kevin's post I'm not sure I understood it the first time. In fact, the more I read it the more confused I get : ) Maybe this will fill in the blanks. The pressure at the port in question is dynamic pressure due to the water pump, not expansion. It might suck some air on cool down when the engine is shut off but will immediately flush it out on startup. The other point is the bottom port of expansion tank should go to the top (outlet) of the pump housing, not the inlet. Therefore there is no bypassing of the radiator. Tracy On Thu, Sep 10, 2009 at 9:31 AM, Tracy Crook wrote: > As Ayn Rand said, "There are no contradictions. If you see one, examine > your premise." > > Why would you want a large flow through the expansion tank? > > Tracy > > On Thu, Sep 10, 2009 at 2:02 AM, kevin lane wrote: > >> I was embarrassed to ask about this originally, but it seems I am not >> alone with questions. having viewed several flying cooling system flow >> designs at the rotary round-up, perhaps it isn't that critical. >> one aspect I trying to understand is the expansion tank. there >> shouldn't a big flow thru there, right? if the pressure is greatest at this >> far rotor housing top port, then it must be lower in the expansion tank, and >> a slow flow will take place towards the expansion tank, right? the small >> diameter line will tend to push bubbles thru and they will separate in the >> expansion tank. so, if they enter the tank above water level, this line will >> suck air from the expansion tank as the cooling fluid cools and has a lesser >> volume, right? not good. if the expansion tank feeds the cooling >> circulation system by T'ing into the water pump output, then it is all on >> the higher pressure side of the system, and the air in the expansion tank >> won't have a tendency to be sucked into the circulation? is the design >> intention to keep the expansion tank under pressure, rather than have it >> part of the flow [circulation]? if the expansion tank was plumbed into >> the water pump inlet port, then a second circulation route is created, which >> doesn't involved the radiator [rear rotor port to tank to water pump, thru >> engine block to rear port....], right? >> as far as the bubble line for the radiator it seems that it would work by >> allowing trapped bubbles in the higher end of the radiator to travel uphill >> to the expansion tank. is the pressure at the radiator also higher, as with >> the rear port? >> enough questions. clear as mud, right? kevin >> > > --00c09f9c99c6b7a39b04733b0c9e Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Re-reading Kevin's post I'm not sure I understood it the first time= .=A0 In fact, the more I read it the more confused I get : )

Maybe t= his will fill in the blanks.=A0 The pressure at the port in question is dyn= amic pressure due to the water pump, not expansion.=A0 It might suck some a= ir on cool down when the engine is shut off but will immediately flush it o= ut on startup.=A0 The other point is the bottom port of expansion tank shou= ld go to the top (outlet) of the pump housing, not the inlet.=A0 Therefore = there is no bypassing of the radiator.

Tracy

On Thu, Sep 10, 2009 at 9:31 AM= , Tracy Crook <tracy@rotaryaviation.com> wrote:
As Ayn Rand said, =A0 "There are no contradictions.=A0 If you see one,= examine your premise."

Why would you want a large flow through= the expansion tank?

Tracy

On Thu= , Sep 10, 2009 at 2:02 AM, kevin lane <n3773@comcast.net> wr= ote:
I was embarrassed to ask about this origi= nally,=20 but it seems I am not alone with questions.=A0 having viewed several flying= =20 cooling system flow designs at the rotary round-up, perhaps it isn't th= at=20 critical.
=A0 one aspect I trying to understand is = the=20 expansion tank.=A0 there shouldn't a big flow thru there, right?=A0 if = the=20 pressure is greatest at this far rotor housing top port, then it must be lo= wer=20 in the expansion tank, and a slow flow will take place towards the expansio= n=20 tank,=A0right?=A0 the small diameter line will tend to push bubbles thru=20 and they will separate in the expansion tank.=A0so, if they enter the tank= =20 above water level, this line will suck=A0air from the expansion tank as the= =20 cooling fluid cools and has a lesser volume, right?=A0not good. =A0 if the= =20 expansion tank feeds the cooling circulation system by T'ing into the w= ater pump=20 output, then it is all on the higher pressure side of the system, and the a= ir in=20 the expansion tank won't have a tendency to be sucked into the=20 circulation?=A0 is the design intention to keep the expansion tank under=20 pressure, rather than have it part of the flow [circulation]?=A0=A0=A0=20 if the expansion tank was plumbed into the water pump inlet port, then a se= cond=20 circulation route is created, which doesn't involved the radiator [rear= rotor=20 port to tank to water pump, thru engine block to rear port....],=20 right?
as far as the bubble line for the radiato= r it=20 seems that it would work by allowing trapped bubbles in the higher end of t= he=20 radiator to travel uphill to the expansion tank.=A0 is the pressure at the= =20 radiator also higher, as with the rear port?
enough questions.=A0 clear as mud,=20 right?=A0=A0 kevin


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