Return-Path: Received: from [216.52.245.18] (HELO ispwestemail2.mdeinc.com) by logan.com (CommuniGate Pro SMTP 4.2.5) with ESMTP id 482428 for flyrotary@lancaironline.net; Thu, 21 Oct 2004 22:35:01 -0400 Received-SPF: none receiver=logan.com; client-ip=216.52.245.18; envelope-from=wschertz@ispwest.com Received: from 7n7z201 (unverified [67.136.146.29]) by ispwestemail2.mdeinc.com (Vircom SMTPRS 3.2.315.0) with SMTP id for ; Thu, 21 Oct 2004 19:34:22 -0700 Message-ID: <028c01c4b7df$a0175450$07928843@7n7z201> From: "William" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Core pressure drop Date: Thu, 21 Oct 2004 21:33:04 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0285_01C4B7B5.8CABF620" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1437 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441 This is a multi-part message in MIME format. ------=_NextPart_000_0285_01C4B7B5.8CABF620 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MessageThe tube with the Wiggins fittings is 1-3/8" tubing, it then = feeds core 1 and has a branch that goes to core 2. The water coming out = of core 1 goes into a side branch of a 1-3/8" tube connected to the = outlet of core 2. The tubes feeding the cores (both inlet and outlet) = are 3/4" tubing. Largest that would fit in the manifold end of the = cores. The interconnecting hose is 3/4" ID, and the hose lengths are equal to = try to get equal flow. I believe that the weakness of my design is entrance losses at the = junction of the 3/4 tube to 1-3/8 tube. Bill Schertz KIS Cruiser # 4045 ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Thursday, October 21, 2004 9:56 AM Subject: [FlyRotary] Core pressure drop Subject: [FlyRotary] Re: nylon EWP's The curves that start at zero and rise as the square of the flow with = data points are measured flow rates through an 'individual' radiator = core [measured both cores, they behaved the same]. I will be running the = cores in parallel, so the curve near the 'real rad test' is a calculated = curve that is the sum of two individual cores. I then plumbed the two evaporator cores into the flow loop, and got a = single point with pressure drop and flow rate for the two in parallel. = Here is the plumbing setup. You have to look hard to see that they = really are plumbed in parallel, but they are. Bill Schertz Bill; What's the i.d. on the aluminum tube and fittings going in and out of = the core, and the connecting line? It looks like the flow velocities = there would be quite high when you get to about 10 or more gpm per core. = What did you estimate for that contribution to the pressure drop. Al KIS Cruiser # 4045 ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Wednesday, October 20, 2004 11:35 PM Subject: [FlyRotary] Re: nylon EWP's Bill; 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. 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 . . = .=20 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 -----=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 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_0285_01C4B7B5.8CABF620 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
The tube with the Wiggins fittings is = 1-3/8"=20 tubing, it then feeds core 1 and has a branch that goes to core 2. The = water=20 coming out of core 1 goes into a side branch of a 1-3/8" tube connected = to the=20 outlet of core 2.  The tubes feeding the cores (both inlet and = outlet) are=20 3/4" tubing. Largest that would = fit in the=20 manifold end of the cores.
 
The interconnecting hose is 3/4" ID, = and the hose=20 lengths are equal to try to get equal flow.
 
I believe that the weakness of my = design is=20 entrance losses at the junction of the 3/4 tube to 1-3/8 = tube.
Bill Schertz
KIS Cruiser # 4045
----- Original Message -----
From:=20 Al = Gietzen=20
Sent: Thursday, October 21, = 2004 9:56=20 AM
Subject: [FlyRotary] Core = pressure=20 drop

Subject:=20 [FlyRotary] Re: nylon EWP's

 

The curves that start at = zero and=20 rise as the square of the flow with data points are measured flow = rates=20 through an 'individual' radiator core [measured both cores, they = behaved the=20 same]. I will be running the cores in parallel, so the curve near the = 'real=20 rad test' is a calculated curve that is the sum of two individual=20 cores.

 

I then plumbed the two = evaporator=20 cores into the flow loop, and got a single point with pressure drop = and flow=20 rate for the two in parallel. Here is the plumbing setup. You have to = look=20 hard to see that they really are plumbed in parallel, but they=20 are.

 

Bill = Schertz

Bill;

What=92s = the i.d. on=20 the aluminum tube and fittings going in and out of the core, and the=20 connecting line?  It looks like the flow velocities there would = be quite=20 high when you get to about 10 or more gpm per core.  What did you = estimate for that contribution to the pressure drop.

 

Al

 

 

 

KIS Cruiser #=20 4045

----- Original Message = -----=20

From: Al = Gietzen=20

To: Rotary motors in = aircraft=20

Sent:=20 Wednesday, October 20, = 2004 11:35=20 PM

Subject:=20 [FlyRotary] Re: nylon EWP's

 

Bill;

 

Good = stuff.=20

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

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

 

Are = the core=20 drops for evaporator cores?  What is the =93Real rad test=94 = data point on=20 the chart?  Ron Davis Racing gave me a pressure drop of 2.25 = psi at 20=20 gpm for the rad I got from them.  Griffin did=20 not provide any pressure drop data on the rad they made for me that = goes in=20 the wing root, but based on the configuration I=92m sure it is = higher. =20 I=92m guessing that my two rads in parallel will get me out close to = 40 gpm at=20 5600 rpm, which is pretty much on my design point.

 

Now = if I just=20 knew what the actual air-side flow was going to be . . . =

 

Al

 

Subject:=20 [FlyRotary] Re: nylon EWP's

 

Okay,

A year or so ago I = posted a=20 graph of measured 13-B water pump performance. I am enclosing it = again with=20 this post. Several points to be made:

 

1. The water pump is = on the=20 engine, so the pressure indicated on the Y axis is the pressure that = is left=20 over to push the water through the radiator = cores.

2. The measurements = were made=20 with 3 different size pulleys, to vary the water pump=20 speed.

3. At no flow, the = pressure on=20 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=20 up by the pressure drop through the block, and there is no more = pressure to=20 force water through the radiator.

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

 

At a later date, Barny = located=20 the full flow (no pressure) and zero flow (max pressure) points = for the=20 Meziere pump. Dead head pressure was 10 psi, and full flow was = ~55gpm. These=20 numbers did NOT have the pressure drop across the core = included. =20 Tomorrow I will forward a graph with this information overlayed on = this=20 chart.

 

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

 

Bill Schertz
KIS = Cruiser #=20 4045

-- Original Message -----=20

From: Al = Gietzen=20

To: Rotary motors in = aircraft=20

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

Subject:=20 [FlyRotary] Re: nylon EWP's

 

 

 

Subject:=20 [FlyRotary] nylon EWP's

 

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

 

Two = in series=20 may not give much more flow than one; depending on the back = pressure vs=20 the pressure at which those flows are based. If those pumps are = rated=20 flow at 0 pressure, it is likely that even the = AL = one is=20 marginal.

 

I=92ve done the=20 math on the 20B.  The flow requirements depends on the = cooling=20 system design (obviously); but if you were to design for a sort = of=20 optimum system for an aircraft, you=92d like to have 20 =96 30 F = temp drop=20 around the loop when you are running about 85% power, say, 220 = HP.=20  So for a 50/50 EG/water mix, and 25F delta T; that says = 39.5 gpm.=20  For pure water the number is 28.5 gpm

 

The = only real=20 data I have on my pump is from the dyno runs.  That showed = 43 gpm=20 at 5000; 48 at 6000.  That is without a thermostat, and on = a large=20 capacity system with presumably relatively low back pressure.=20  25-30% less with a thermostat.  Unfortunately, I = don=92t know=20 what it is on the airplane.

 

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