X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from poplet2.per.eftel.com ([203.24.100.45] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3753955 for flyrotary@lancaironline.net; Sat, 11 Jul 2009 18:06:04 -0400 Received-SPF: none receiver=logan.com; client-ip=203.24.100.45; envelope-from=lendich@aanet.com.au Received: from sv1-1.aanet.com.au (sv1-1.per.aanet.com.au [203.24.100.68]) by poplet2.per.eftel.com (Postfix) with ESMTP id 5BF821737C0 for ; Sun, 12 Jul 2009 06:05:26 +0800 (WST) Received: from ownerf1fc517b8 (203.171.92.134.static.rev.aanet.com.au [203.171.92.134]) by sv1-1.aanet.com.au (Postfix) with SMTP id 3AF03BEC001 for ; Sun, 12 Jul 2009 06:05:24 +0800 (WST) Message-ID: <0931CF01BF764863850F9053521872B1@ownerf1fc517b8> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Exit Area [FlyRotary] Re: Water Spray Pump Date: Sun, 12 Jul 2009 08:05:26 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002C_01CA02C7.839E7D70" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Antivirus: avast! (VPS 090711-0, 07/11/2009), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_002C_01CA02C7.839E7D70 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ed,=20 I have been looking through my notes and I can't see any notation on = optimum inlet area as compared to rad area, so is that 25-30% surface = area or volume of rad. My notes say exit area should be 135% or 1.35 = times inlet area. Pressure build up behind the Rad is a major problem which may be = resolved with exhaust augmentation, sucking the air from the cowl area. = Another way may be to have a fan sucking air from the cowl or develop = some low pressure suction to the cowl. One of the reasons I'm looking at the round rad is that outlet can be = controlled with a simple butterfly. George (down under) Hi Bobby, =20 The theory I have read indicates that once your open area has passed = 25-30% of your core area, that from that point on - exit area dominates. = In other words, it does not make much difference how much more you = enlarge your inlet area if the air can not get out. Air pressure simply = builds under the cowl in back of the core and restricts further = enhancement of thorough flow. That is if I understood what I read = correctly. =20 Ed =20 Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://www.dmack.net/mazda/index.html http://www.flyrotary.com/ http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.rotaryaviation.com/Rotorhead%20Truth.htm -------------------------------------------------------------------------= ----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Bobby J. Hughes Sent: Saturday, July 11, 2009 3:52 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Water Spray Pump=20 =20 Bill, =20 I don't think I have a problem getting air out of the cowl. The exit = area is greater than 3X the size of my inlets with no restrictions. The = inlet ducts and wedge diffusers tested very good on a bench wind tunnel = setup. But I need to review that data to make sure it's close to my = actual flight data. I really don't have any other options for my = radiator inlets other than a small enlargement. My radiators are 2.75" = thick and have a denser fin count than the Griffin type Dennis and Tracy = are flying. I expect Air Delta T to be better than 81F.=20 =20 Any difference in controlling the inlet air verses traditional cowl = flaps on the exit? =20 Bobby =20 =20 =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Bill Schertz Sent: Saturday, July 11, 2009 12:07 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Water Spray Pump=20 Time I chimed in. I have been testing with short flights trying to get = my temps in line. I cannot stay at full throttle beyond climbing to = ~2500, at which point I throttle back to 5600 - 6000 rpm, and bring the = speed up to 110 knots. Temps then stabilize below 200 - 205. =20 As part of my diagnostics, I have always had a air pressure = differential measurement from my Blue Mountain (sigh) unit, and it would = indicate ~3 to max 4 inches of water pressure difference between the = front of the rad and behind it under the cowl. =20 For further information, I have installed a temporary set of pressure = probes that run to a manometer in the cabin. This has told me the = following: =20 1. The entrance to the rad is getting good pressure 6-7 inches water = pressure, but 2. The exit is not functioning well enough, because I get 3-4 inches = pressure under the cowl. =20 My theory as to why this is difficult to fully cool includes. =20 1. The cowl was designed for an air cooled engine, rejecting heat at = 350 cylinder head temperature, which is a bigger driving force than we = have. 2. I used the two cowl inlets in the original cowl to supply the two = rads. 3. I have a third entrance for the oil cooler, so I have ~ 50% more = airflow to get out of the cowl. =20 Bobby, I would install some manometers to see if it is a problem = getting the air in -- or out before you modify your cowling. Bill Schertz KIS Cruiser #4045 N343BS Phase I testing ----- Original Message -----=20 From: Bobby J. Hughes=20 To: Rotary motors in aircraft=20 Sent: Saturday, July 11, 2009 10:44 AM Subject: [FlyRotary] Water Spray Pump=20 =20 Like Dennis I am having to throttle back and reduce boost after = reaching pattern altitude. Flight testing this week showed I can = stabilize my oil temp at 220F at 130 mph, 6400 rpm and 30" MP. Air Delta = T after my radiators averaged 81F. This power setting gives a 600 fpm = climb and about 185-190 HP. Not very impressive for a RV10. My initial = climb out was around 1000-1250 fpm with OAT at 95F. Water temp = stabilized at 200F. My oil to water exchanger was transferring 43F to = the water.=20 =20 My total inlet area is 58 sqin and 21% of core face. The numbers = indicate that opening my inlet area to 68 sqin or 25% should allow me to = cool my full net 238 HP. Before starting major fiberglass work at 102 F = I am thinking of testing a super fine mist on the radiators. I would = like to see what my oil temps would be if I can drop the water temp by = 10-20 degrees. The pump information attached is a 15 bar pump and meets = the specification for continuous use and is safe to run dry. It's an = espresso machine type pump but does not have on\off time limitations. = Other pumps like his have a 1/1 or 2/1 On/Off in minutes for cooling. = If lowering my water temps to 180-185F has a positive effect on oil = temps then I will open my radiator duct this fall when it's cooler. = Besides, I have another test for this pump. I don't have an intercooler = and having a 1 pound 15 bar pump will tempt me to test manifold water = injections after my super charger.=20 =20 Bobby RV-10 SC Renesis. =20 -------------------------------------------------------------------------= --- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html __________ Information from ESET NOD32 Antivirus, version of virus = signature database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ------=_NextPart_000_002C_01CA02C7.839E7D70 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Ed,
I have been looking through my notes = and I can't=20 see any notation on optimum inlet area as compared to rad area, so is = that=20 25-30% surface area or volume of rad. My notes say exit area should be = 135% or=20 1.35 times inlet area.
 
Pressure build up behind the Rad is a = major problem=20 which may be resolved with exhaust augmentation, sucking the air from = the cowl=20 area. Another way may be to have a fan sucking air from the cowl or = develop some=20 low pressure suction to the cowl.
 
One of the reasons I'm looking at the = round rad is=20 that outlet can be controlled with a simple butterfly.
George (down under)

Hi=20 Bobby,

 

The theory = I have=20 read indicates that once your open area has passed 25-30% of your core = area,=20 that from that point on - exit area dominates. In other words, it does = not=20 make much difference how much more you enlarge your inlet area if the = air can=20 not get out.  Air pressure simply builds under the cowl in back = of the=20 core and restricts further enhancement of thorough flow.  That is = if I=20 understood what I read correctly.

 

Ed

 

Ed=20 Anderson

Rv-6A = N494BW Rotary=20 Powered

Matthews,=20 NC

eanderson@carolina.rr.com

http://www.andersonee.com

http://www.dmack.net/mazda/index.html

http://www.flyrotary.com/

http://members.cox.net/rogersda/rotary/configs.htm#N494BW

http://www.r= otaryaviation.com/Rotorhead%20Truth.htm

From:=20 Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On=20 Behalf Of Bobby J. Hughes
Sent: Saturday, July 11, 2009 = 3:52=20 PM
To: = Rotary motors in aircraft
Subject: [FlyRotary] Re: Water = Spray Pump=20

 

Bill,

 

I don't = think I=20 have a problem getting air out of the cowl.  The exit = area is=20 greater than 3X the size of my inlets with no restrictions. The inlet = ducts=20 and wedge diffusers tested very good on a bench wind tunnel setup. But = I need=20 to review that data  to make sure it's close to = my actual=20 flight data. I really don't have any other options for = my=20 radiator inlets other than a small enlargement.  My = radiators are=20  2.75" thick and have a denser fin count than the Griffin = type Dennis=20 and Tracy are flying. I expect Air Delta T to be better than 81F.=20

 

Any difference=20 in controlling the inlet air verses traditional cowl flaps on the=20 exit?

 

Bobby

 

 

 

 

 From:=20 Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On=20 Behalf Of Bill Schertz
Sent: Saturday, July 11, 2009 = 12:07=20 PM
To: = Rotary motors in aircraft
Subject: [FlyRotary] Re: Water = Spray Pump=20

Time I chimed in. I have = been=20 testing with short flights trying to get my temps in line. I cannot = stay at=20 full throttle beyond climbing to ~2500, at which point I throttle back = to 5600=20 - 6000 rpm, and bring the speed up to 110 knots. Temps then stabilize = below=20 200 - 205.

 

As part of my = diagnostics, I have=20 always had a air pressure differential measurement from my Blue = Mountain=20 (sigh) unit, and it would indicate ~3 to max 4 inches of water = pressure=20 difference between the front of the rad and behind it under the=20 cowl.

 

For further information, = I have=20 installed a temporary set of pressure probes that run to a manometer = in the=20 cabin. This has told me the = following:

 

1. The entrance to the = rad is=20 getting good pressure 6-7 inches water pressure,=20 but

2. The exit is not = functioning=20 well enough, because I get 3-4 inches pressure under the=20 cowl.

 

My theory as to why this = is=20 difficult to fully cool includes.

 

1. The cowl was designed = for an=20 air cooled engine, rejecting heat at 350 cylinder head temperature, = which is a=20 bigger driving force than we have.

2. I used the two cowl = inlets in=20 the original cowl to supply the two = rads.

3. I have a third = entrance for the=20 oil cooler, so I have ~ 50% more airflow to get out of the=20 cowl.

 

Bobby, I would install = some=20 manometers to see if it is a problem getting the air in -- or out = before you=20 modify your cowling.

Bill Schertz
KIS Cruiser #4045
N343BS
Phase I=20 testing

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

From: Bobby J. = Hughes=20

To: Rotary motors in = aircraft=20

Sent:=20 Saturday, July 11, 2009 10:44 AM

Subject:=20 [FlyRotary] Water Spray Pump

 

Like Dennis I am = having to=20 throttle back and reduce boost after reaching pattern altitude. = Flight=20 testing this week showed I can stabilize my oil temp at 220F at 130 = mph,=20 6400 rpm and 30" MP. Air Delta T after my radiators averaged=20 81F. This power setting gives a 600 fpm climb and about 185-190 = HP. Not=20 very impressive for a RV10. My initial climb out was around = 1000-1250=20 fpm with OAT at 95F. Water temp stabilized at 200F. =  My oil=20 to water exchanger was transferring 43F to the water.=20

 

My total inlet area is = 58 sqin=20 and 21% of core face. The numbers indicate that opening my inlet = area to 68=20 sqin or 25% should allow me to cool my full net 238 HP.  = Before=20 starting major fiberglass work at 102 F I am thinking of testing a = super=20 fine mist on the radiators. I would like to see what my oil = temps would=20 be if I can drop the water temp by 10-20 degrees. The pump = information=20 attached is a 15 bar pump and meets the specification for continuous = use and=20 is safe to run dry. It's an espresso machine type pump but does not=20 have on\off time limitations. Other pumps like his have a 1/1 = or 2/1=20 On/Off in minutes for cooling.  If lowering my water temps to = 180-185F=20 has a positive effect on oil temps then I will open my radiator duct = this=20 fall when it's cooler. Besides, I have another test for this pump. I = don't=20 have an intercooler and having a 1 pound 15 bar pump will tempt me = to test=20 manifold water injections after my super charger.=20

 

Bobby

RV-10 SC=20 Renesis.

 

--
Homepage: =20 http://www.flyrotary.com/
Archive and UnSub:  =20 = http://mail.lancaironline.net:81/lists/flyrotary/List.html



__________ Information from ESET = NOD32=20 Antivirus, version of virus signature database 3267 (20080714)=20 __________

The message was checked by ESET NOD32 = Antivirus.

http://www.eset.com

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