Return-Path: Received: from fed1rmmtao07.cox.net ([68.230.241.32] verified) by logan.com (CommuniGate Pro SMTP 4.2.5) with ESMTP id 481181 for flyrotary@lancaironline.net; Thu, 21 Oct 2004 00:35:39 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.32; envelope-from=ALVentures@cox.net Received: from BigAl ([68.107.116.221]) by fed1rmmtao07.cox.net (InterMail vM.6.01.03.04 201-2131-111-106-20040729) with ESMTP id <20041021043510.GZZX9907.fed1rmmtao07.cox.net@BigAl> for ; Thu, 21 Oct 2004 00:35:10 -0400 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: nylon EWP's Date: Wed, 20 Oct 2004 21:35:14 -0700 Message-ID: <000001c4b727$5bb54370$6400a8c0@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C4B6EC.AF566B70" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C4B6EC.AF566B70 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Bill; =20 Good stuff.=20 The flow curve shown for my dyno run, http://members.cox.net/alg3/Dynamometer%20test%20report.htm is pumping through the engine and through the large radiator of the facility. I think the pump on my 20B is geared about 1:1 with the = e-shaft. For the same RPMs, my data correlate reasonably well with yours at 0 backpressure across the radiator. =20 Are the core drops for evaporator cores? What is the "Real rad test" = data point on the chart? Ron Davis Racing gave me a pressure drop of 2.25 = psi at 20 gpm for the rad I got from them. Griffin did not provide any = pressure drop data on the rad they made for me that goes in the wing root, but = based on the configuration I'm sure it is higher. I'm guessing that my two = rads in parallel will get me out close to 40 gpm at 5600 rpm, which is pretty much on my design point. =20 Now if I just knew what the actual air-side flow was going to be . . .=20 =20 Al =20 Subject: [FlyRotary] Re: nylon EWP's =20 Okay, A year or so ago I posted a graph of measured 13-B water pump = performance. I am enclosing it again with this post. Several points to be made: =20 1. The water pump is on the engine, so the pressure indicated on the Y = axis is the pressure that is left over to push the water through the radiator cores. 2. The measurements were made with 3 different size pulleys, to vary the water pump speed. 3. At no flow, the pressure on the Y axis is the maximum pressure that = the pump can supply. At zero pressure, max flow, all the available head = pressure from the pump is taken up by the pressure drop through the block, and = there is no more pressure to force water through the radiator. 4. Looking at the charts, you can see that at a flow of 20 gpm, the = pressure drop across the core is 5 psi, at 33 gpm the drop across the core is 8.5 psi, and at 44 gpm, the drop across the core is 19 psi. =20 At a later date, Barny located the full flow (no pressure) and zero flow (max pressure) points for the Meziere pump. Dead head pressure was 10 = psi, and full flow was ~55gpm. These numbers did NOT have the pressure drop across the core included. Tomorrow I will forward a graph with this information overlayed on this chart. =20 Based on these TESTS, and the CLAIMED performance (by the manufacturer) = of the EWP, I calculate that you can get ~ 20gpm max through an engine core combination. If you need more you will start to have heat extraction problems. =20 Bill Schertz KIS Cruiser # 4045 -- Original Message -----=20 From: Al Gietzen =20 To: Rotary motors in aircraft=20 Sent: Wednesday, October 20, 2004 1:45 PM Subject: [FlyRotary] Re: nylon EWP's =20 =20 =20 Subject: [FlyRotary] nylon EWP's =20 I'd like to hear some more comments about nylon vs. AL EWP's. should I = be satisfied with "well, Leon uses them" and ask no more? the nylon pumps = seem light enough, 2 lbs., that they could be supported simply by their = rubber hoses, which should make a good vibration damper. (I don't really know = who Leon is, although I get the impression his word rates right up there = with Tracy's) the nylon ones only push 20 gpm, whereas the AL claim 37 gpm. = I have no idea what my 20B will require. I would be using 2 in series. =20 Two in series may not give much more flow than one; depending on the = back pressure vs the pressure at which those flows are based. If those pumps = are rated flow at 0 pressure, it is likely that even the AL one is marginal. =20 I've done the math on the 20B. The flow requirements depends on the = cooling system design (obviously); but if you were to design for a sort of = optimum system for an aircraft, you'd like to have 20 - 30 F temp drop around = the loop when you are running about 85% power, say, 220 HP. So for a 50/50 EG/water mix, and 25F delta T; that says 39.5 gpm. For pure water the number is 28.5 gpm =20 The only real data I have on my pump is from the dyno runs. That showed = 43 gpm at 5000; 48 at 6000. That is without a thermostat, and on a large capacity system with presumably relatively low back pressure. 25-30% = less with a thermostat. Unfortunately, I don't know what it is on the = airplane. =20 ------=_NextPart_000_0001_01C4B6EC.AF566B70 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message

Bill;

 

Good stuff.

The flow curve shown for my dyno run,  http= ://members.cox.net/alg3/Dynamometer%20test%20report.htm=

 is pumping through the engine and through the = large radiator of the facility.  I think the pump on my 20B is geared = about 1:1 with the e-shaft.  For the same RPMs, my data correlate reasonably = well with yours at 0 backpressure across the radiator.

 

Are the core drops for evaporator cores?  What = is the “Real rad test” data point on the chart?  Ron Davis = Racing gave me a pressure drop of 2.25 psi at 20 gpm for the rad I got from = them.  Griffin did not provide any pressure drop data on the rad they made for me that goes in = the wing root, but based on the configuration I’m sure it is = higher.  I’m guessing that my two rads in parallel will get me out close to 40 gpm at = 5600 rpm, which is pretty much on my design point.

 

Now if I just knew what the actual air-side flow = was going to be . . .

 

Al

 

Subject: [FlyRotary] Re: nylon EWP's

 

Okay,

A year or so ago I posted a = graph of measured 13-B water pump performance. I am enclosing it again with this = post. Several points to be made:

 

1. The water pump is on the = engine, so the pressure indicated on the Y axis is the pressure that is left = over to push the water through the radiator cores.

2. The measurements were = made with 3 different size pulleys, to vary the water pump speed.

3. At no flow, the pressure = on the Y axis is the maximum pressure that the pump can supply. At zero pressure, = max flow, all the available head pressure from the pump is taken up by the = pressure drop through the block, and there is no more pressure to force water = through the radiator.

4. Looking at the charts, = you can see that at a flow of 20 gpm, the pressure drop across the core is 5 = psi, at 33 gpm the drop across the core is 8.5 psi, and at 44 gpm, the drop across = the core is 19 psi.

 

At a later date, Barny = located the full flow (no pressure) and zero flow (max pressure) points for the Meziere pump. Dead head pressure was 10 psi, and full flow was ~55gpm. = These numbers did NOT have the pressure drop across the core included.  = Tomorrow I will forward a graph with this information overlayed on this = chart.

 

Based on these TESTS,  = and the CLAIMED performance (by the manufacturer) of the EWP, I calculate that = you can get ~ 20gpm max through an engine core combination. If you need more you = will start to have heat extraction problems.

 

Bill Schertz
KIS Cruiser # 4045

-- Original Message -----

=

From: Al = Gietzen

Sent: Wednesday, October 20, 2004 1:45 PM

Subject: [FlyRotary] Re: nylon EWP's

 

 

 

Subject: [FlyRotary] nylon EWP's

 

I'd like to hear = some more comments about nylon vs. AL EWP's.  should I be satisfied with = "well, Leon uses them" and ask no more?  the nylon pumps seem light = enough, 2 lbs., that they could be supported simply by their rubber = hoses, which should make a good vibration damper. (I don't really know who = Leon is, although I get the impression his word rates right up there with = Tracy's) the nylon ones only push 20 gpm, whereas the AL claim 37 gpm.  I have no idea what my 20B will require.  I = would be using 2 in series.

=

 

Two in series may not give much more flow than one; depending on the back = pressure vs the pressure at which those flows are based. If those pumps are rated = flow at 0 pressure, it is likely that even the AL one is = marginal.

 

I’ve done the math on the 20B.  The flow requirements depends on the = cooling system design (obviously); but if you were to design for a sort of = optimum system for an aircraft, you’d like to have 20 – 30 F temp = drop around the loop when you are running about 85% power, say, 220 HP. =  So for a 50/50 EG/water mix, and 25F delta T; that says 39.5 gpm.  For = pure water the number is 28.5 gpm

 

The only real data I have on my pump is from the dyno runs.  That = showed 43 gpm at 5000; 48 at 6000.  That is without a thermostat, and on a = large capacity system with presumably relatively low back pressure. =  25-30% less with a thermostat.  Unfortunately, I don’t know what it is on = the airplane.

 

------=_NextPart_000_0001_01C4B6EC.AF566B70--