X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.120] verified) by logan.com (CommuniGate Pro SMTP 5.1.12) with ESMTP id 2373631 for flyrotary@lancaironline.net; Sun, 07 Oct 2007 08:25:18 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.120; envelope-from=eanderson@carolina.rr.com Received: from edward2 ([24.74.103.61]) by cdptpa-omta01.mail.rr.com with SMTP id <20071007122438.WXRN4058.cdptpa-omta01.mail.rr.com@edward2> for ; Sun, 7 Oct 2007 12:24:38 +0000 Message-ID: <001101c808dd$11f850a0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: Duct?[FlyRotary] Re: Coolant Water Pressure Date: Sun, 7 Oct 2007 08:24:55 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_000E_01C808BB.8AA3DB40" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3138 This is a multi-part message in MIME format. ------=_NextPart_000_000E_01C808BB.8AA3DB40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Yes, 360 deg of turning does not help the air flow, mainly because the = boundary layer in the duct is being put to the test to stay attached = during that 180 deg turn. If you get separation of the boundary layer = and macro air flow in that turn creating eddies in the flow, then = pressure recovery and smooth flow suffers. However, at the low duct = velocities likely in your testing, I'm not certain that flow separation = would be the problem that it may be at higher duct velocities like when = flying. The basic challenge is to find the reason(s) that with 740 ci of core = you are not cooling even at 2200 rpm. Probably the quickest one to = confirm or eliminate is air in the system. Touching or otherwise = measuring the temperature profile of the radiator side tanks should be = sufficient to let you know whether entrapped air is significant or not. =20 It is my opinion that the area from your inlet to the face of your = radiator is not the major problem area - despite the 180 deg turn. I = think its more likely that the air exiting the radiator that could be a = part of the problem. After exiting the core, the air now has no duct to = gentle guide it toward an exit. It must first face the under the cowl = pressure which can oppose the flow and then after it exits the radiator = under the cowl, it must find its way around various obstructions, mainly = the engine, before it makes the final 180 deg turn and exits the cowl = area. If you try operating with the cowl off the prop blast might = interfere with air exiting the core. =20 Was your test run with the cowl off or on? I presume your cowl exits are on the bottom of your cowl?? =20 By the way, Bill, good to see you not getting discouraged- this is a = solvable problem. My challenge was oil temps, I try 5 different = modifications (each with an incremental improvement) until finally = arriving at the solution - which drop oil temps 30F and coolant temps = followed them down. Needless to say, finding the actual root case of = each problem is essential, before formulating corrective action. =20 Hang in there Ed ----- Original Message -----=20 From: Bill Bradburry=20 To: Rotary motors in aircraft=20 Sent: Saturday, October 06, 2007 10:03 PM Subject: [FlyRotary] Re: Duct?[FlyRotary] Re: Coolant Water Pressure Yes, the air will come in from the nostril, make a 180 degree turn, go = through the radiator, make a 180 degree turn, and exit the cowl.after = that I don't know what it will do..but I am sure it will be dizzy!!! =20 Bill B =20 -------------------------------------------------------------------------= ----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Ed Anderson Sent: Saturday, October 06, 2007 7:30 PM To: Rotary motors in aircraft Subject: [FlyRotary] Duct?[FlyRotary] Re: Coolant Water Pressure =20 Bill, do I interpret your explanation of your duct below correctly. = You pull your air in from up front of the cowl and then route it via the = duct to the firewall side of the radiator (the side not shown in the = photo) and then have it flow through the core and exit up into the cowl? =20 Ed ----- Original Message -----=20 From: Bill Bradburry=20 To: Rotary motors in aircraft=20 Sent: Saturday, October 06, 2007 7:10 PM Subject: [FlyRotary] Re: Coolant Water Pressure =20 Yes, Kelly. There is a duct that brings air from the left nostril back to the = rear of the radiator. You can just see it as it comes around the corner = at the lower right side of the picture. There is a plenum that diffuses = this air to cover the radiator core and forces all the air that comes = into the nostril to go through the radiator. When I did a tuft test on = the face of the radiator, I got a pretty good flow over the entire face = of the radiator. However, I had a stronger flow at the bottom. That is = part of what caused me to try the fan. That and I felt that I would = need more air flow than was provided through the nostril by prop blast = when ground running. I do not think the fan will be needed at speed in = flight and in fact, may be an impediment at that time. =20 Bill B =20 -------------------------------------------------------------------------= --- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Kelly Troyer Sent: Saturday, October 06, 2007 1:01 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Coolant Water Pressure =20 Bill, I do not see any sign of ducting to force air through the radiator = instead of around it........Do you have ducting that is not in the photo ?? -- Kelly Troyer=20 "Dyke Delta"_13B ROTARY Engine=20 "RWS"_RD1C/EC2/EM2=20 "Mistral"_Backplate/Oil Manifold=20 =20 -------------- Original message from "Bill Bradburry" = : --------------=20 Ok, I recently upgraded my computer to Vista and had to download = some software to get my camera to talk to it.So here are some pictures = of my cooling install =20 Notice the bypass hole that you guys are talking about needing to = plug. This hole is in the housing which has been removed, so it is not = a player. The little rag you see on the oil line is a high tech way of = checking for a leak. (I have one!) =20 The red wire is the air temp sensor for the air after the = radiator. It is on top of the fan. Hoses are 1 =BC" The temperature sensor was moved from the left = side of the inlet to the top But is reading temperature as it enters the engine after the = radiator. (coolest place) =20 My overflow catch can. I will be replacing this with a = pressurized on as per Lynn's suggestions in a previous post in order to = introduce=20 An air cushion above the liquid under pressure so it will not be = "locked". =20 I am planning to try and put suction on the cowling at the exit = with a leaf blower in addition to the prop blast and the small fan to = see if an increase in=20 Air flowing will help. I haven't checked the sides of the = radiator yet as I have been alone when running the engine.. All inputs appreciated. I already know some things should be = changed, so don't hold back with the suggestions. =20 Thanks, Bill B =20 ------=_NextPart_000_000E_01C808BB.8AA3DB40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Yes, 360 deg of turning does not help the air=20 flow, mainly because the boundary layer in the duct is being = put to=20 the test to stay attached during that 180 deg turn.  If you get = separation=20 of the boundary layer and macro air flow in that turn creating = eddies in=20 the flow, then pressure recovery and smooth flow suffers.   = However,=20 at the low duct velocities likely in your testing, I'm not certain that = flow=20 separation would be the problem that it may be at higher duct velocities = like=20 when flying.
 
The basic challenge is = to find the=20 reason(s) that with 740 ci of core you are not cooling even at 2200 = rpm. =20 Probably the quickest one to confirm or eliminate is air in the = system. =20 Touching or otherwise measuring the temperature profile of the radiator = side=20 tanks should be sufficient to let you know whether entrapped air is = significant=20 or not.
 
 
 It is my opinion that the area from your =  inlet=20 to the face of your radiator is not the major problem area - despite the = 180 deg=20 turn.   I think its more likely that the air exiting the = radiator that=20 could be a part of the problem.  After exiting the core, the air = now has no=20 duct to gentle guide it toward an exit.  It must first face the = under the=20 cowl pressure which can oppose the flow and then after it exits the = radiator=20 under the cowl, it must find its way around various obstructions, mainly = the=20 engine, before it makes the final 180 deg turn and exits the cowl = area.  If=20 you try operating with the cowl off the prop blast might interfere with = air=20 exiting the core. 
 
Was  your test run with the cowl off or=20 on?
 
I presume your cowl exits are on the bottom of = your=20 cowl?? 
 
By the way, Bill, good to see you not getting = discouraged-=20 this is a solvable problem.  My challenge was oil temps, I try 5 = different=20 modifications (each with an incremental improvement) until finally = arriving at=20 the solution - which drop oil temps 30F and coolant temps followed them=20 down.  Needless to say, finding the actual root case of each = problem is=20 essential, before formulating corrective action.    =
 
Hang in there
 
Ed
 
 
 
 
----- Original Message -----
From:=20 Bill=20 Bradburry
Sent: Saturday, October 06, = 2007 10:03=20 PM
Subject: [FlyRotary] Re: = Duct?[FlyRotary]=20 Re: Coolant Water Pressure

Yes, the = air will=20 come in from the nostril, make a 180 degree turn, go through the = radiator,=20 make a 180 degree turn, and exit the cowl=85after that I don=92t know = what it will=20 do=85.but I am sure it will be dizzy!!!

 

Bill=20 B

 

From:=20 Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On=20 Behalf Of Ed Anderson
Sent: Saturday, October 06, = 2007 7:30=20 PM
To: = Rotary motors in aircraft
Subject: [FlyRotary] = Duct?[FlyRotary] Re:=20 Coolant Water Pressure

 

Bill, do I interpret = your=20 explanation of your duct below correctly.  You pull your air in = from up=20 front of the cowl and then route it via the duct to the firewall side = of the=20 radiator (the side not shown in the photo) and then have it flow = through the=20 core and exit up into the = cowl?

 

Ed

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

From: Bill=20 Bradburry

To: Rotary motors in = aircraft=20

Sent:=20 Saturday, October 06, 2007 7:10 = PM

Subject:=20 [FlyRotary] Re: Coolant Water = Pressure

 

Yes,=20 Kelly.

There is = a duct=20 that brings air from the left nostril back to the rear of the=20 radiator.  You can just see it as it comes around the corner at = the=20 lower right side of the picture.  There is a plenum that = diffuses this=20 air to cover the radiator core and forces all the air that comes = into the=20 nostril to go through the radiator.  When I did a tuft test on = the face=20 of the radiator, I got a pretty good flow over the entire face of = the=20 radiator.  However, I had a stronger flow at the bottom.  = That is=20 part of what caused me to try the fan.  That and I felt that I = would=20 need more air flow than was provided through the nostril by prop = blast when=20 ground running.  I do not think the fan will be needed at speed = in=20 flight and in fact, may be an impediment at that=20 time.

 

Bill=20 B

 

From:=20 Rotary motors in = aircraft=20 [mailto:flyrotary@lancaironline.net] On=20 Behalf Of Kelly Troyer
Sent: Saturday, October 06, = 2007 1:01=20 PM
To: = Rotary motors in aircraft
Subject: [FlyRotary] Re: = Coolant Water=20 Pressure

 

Bill,

  I do not see any sign of ducting to = force air=20 through the radiator instead of = around

it........Do you have ducting that is not = in the=20 photo ??

--
Kelly Troyer =
"Dyke Delta"_13B=20 ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil = Manifold=20

 

--------------=20 Original message from "Bill Bradburry" = <bbradburry@bellsouth.net>:=20 --------------

Ok, I = recently=20 upgraded my computer to Vista and had to download some = software=20 to get my camera to talk to it=85So here are some pictures of my = cooling=20 install

 

Notice = the bypass=20 hole that you guys are talking about needing to plug.  This = hole is=20 in the housing which has been removed, so it is not a=20 player.

The = little rag=20 you see on the oil line is a high tech way of checking for a leak. = (I have=20 one!)

 

The red = wire is=20 the air temp sensor for the air after the radiator.  It is on = top of=20 the fan.

Hoses = are 1=20 =BC=94  The temperature sensor was moved from the left side = of the inlet=20 to the top

But is = reading=20 temperature as it enters the engine after the radiator. (coolest=20 place)

 

My = overflow catch=20 can.  I will be replacing this with a pressurized on as per = Lynn=92s = suggestions=20 in a previous post in order to introduce =

An air = cushion=20 above the liquid under pressure so it will not be=20 =93locked=94.

 

I am = planning to=20 try and put suction on the cowling at the exit with a leaf blower = in=20 addition to the prop blast and the small fan to see if an increase = in=20

Air = flowing will=20 help.  I haven=92t checked the sides of the radiator yet as I = have been=20 alone when running the engine=85.

All = inputs=20 appreciated.  I already know some things should be changed, = so don=92t=20 hold back with the suggestions.

 

Thanks,

Bill=20 B

 

------=_NextPart_000_000E_01C808BB.8AA3DB40--