Return-Path: <13brv3@bellsouth.net> Received: from imf24aec.mail.bellsouth.net ([205.152.59.72] verified) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2641737 for flyrotary@lancaironline.net; Sat, 18 Oct 2003 11:45:26 -0400 Received: from rad ([68.212.14.231]) by imf24aec.mail.bellsouth.net (InterMail vM.5.01.05.27 201-253-122-126-127-20021220) with ESMTP id <20031018154523.TLEP1789.imf24aec.mail.bellsouth.net@rad> for ; Sat, 18 Oct 2003 11:45:23 -0400 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] EWP Series vs PARALLEL pumps & flowmeter Date: Sat, 18 Oct 2003 10:45:25 -0500 Message-ID: <006901c3958e$d946b410$6001a8c0@rad> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_006A_01C39564.F070AC10" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.4510 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 This is a multi-part message in MIME format. ------=_NextPart_000_006A_01C39564.F070AC10 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable My idea is that the most efficient use of a dual (redundant) EWP set-up is that they should be run in PARALLEL with two simple non return valves. Yep, sure it's a bit more complicated to engineer, but I believe it is worth the extra effort. I'm betting that no one will argue the contrary. I think the only = problem with parallel is the packaging. Once I get a big pile of new parts on = the floor, I'll have to spend many hours deciding what the best way to fit = them in the cowl will be. Realistically, nothing is going to get done before December at the earliest. I will certainly be trying to figure out how = to do the parallel pumps though. =20 With EWPs, a switching mechanism can be arranged so that the second pump will come on and off automatically whenever the water temp goes over or under pre-set limits. An ordinary thermoswitch of the type used for auto radiator fans - especially the auxillary air cond fan(s) are pretty reliable. =20 What are your thoughts (in 5000 words or less ) about using temp to notice the failure of a pump? In other words, you're flying along with = only one pump running, and it fails. How long do you think it will take = before the aux pump will kick in due to the higher temp? More importantly, = what do you figure the chances of boiling out coolant, or damaging the engine = will be before the aux pump comes online? I'm betting that you and Lynn = (who's also been mighty quiet on this subject) have had seen failures than all = the rest of us combined.=20 Thanks, Rusty =20 =20 ------=_NextPart_000_006A_01C39564.F070AC10 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable Message

My idea is that the most efficient use of a dual = (redundant)=20 EWP
set-up is that they should be run in PARALLEL with two = simple
non=20 return valves. Yep,  sure it's a bit more complicated = to
engineer, =20 but I believe it is worth the extra effort.

I'm = betting that no one=20 will argue the contrary. I think the only problem with parallel is the=20 packaging.  Once I get a big pile of new parts on the floor, = I'll have=20 to spend many hours deciding what the best way to fit them in the = cowl will=20 be.  Realistically, nothing is going to get done before December at = the earliest.  I will certainly be trying to figure out how to = do the=20 parallel pumps though.   

With EWPs,  a switching mechanism can be arranged so that = the
second=20 pump will come on and off automatically whenever the
water temp goes = over or=20 under pre-set limits.    An ordinary
thermoswitch of = the type=20 used for auto radiator fans - especially the
auxillary air cond = fan(s) are=20 pretty reliable. 

What are your = thoughts (in 5000=20 words or less <g>) about using temp to notice the failure of = a=20 pump?  In other words, you're flying along with only one pump = running, and=20 it fails.  How long do you think it will take before the aux = pump will=20 kick in due to the higher temp?  More importantly, what do you = figure=20 the chances of boiling out coolant, or damaging the engine will be = before=20 the aux pump comes online?  I'm betting that you and Lynn (who's = also been=20 mighty quiet on this subject) have had seen failures than all the rest = of us=20 combined. 

Thanks,
Rusty    


 

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