X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [66.219.56.245] (HELO mail.qnsi.net) by logan.com (CommuniGate Pro SMTP 5.4.4) with ESMTP id 5432309 for flyrotary@lancaironline.net; Wed, 07 Mar 2012 12:21:37 -0500 Received-SPF: none receiver=logan.com; client-ip=66.219.56.245; envelope-from=bhughes@qnsi.net Content-class: urn:content-classes:message Return-Receipt-To: "Bobby J. Hughes" MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01CCFC86.ACD0DA2D" Disposition-Notification-To: "Bobby J. Hughes" Subject: RE: [FlyRotary] Re: Ground Cooling X-MimeOLE: Produced By Microsoft Exchange V6.5 Date: Wed, 7 Mar 2012 11:21:03 -0600 Message-ID: <74120FDE88CAFE4DBDA8814BCE20A3F33B7AF3@qnsi-mail.qnsi.net> In-Reply-To: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: Ground Cooling Thread-Index: Acz8hICAxPNpLljfT8ikq2wysyByMAAADqxQ References: From: "Bobby J. Hughes" To: "Rotary motors in aircraft" This is a multi-part message in MIME format. ------_=_NextPart_001_01CCFC86.ACD0DA2D Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Chris, =20 My personal coolant limit is 210F. I sometimes see 200F on climb out. I = anticipate a 25-30F rise as part of my go/no-go decision. My coolant = after normal taxi has been 170-175F. Cruise is usually 170-180F = depending on OAT and power settings. Long flights at high altitude I can = see as low as 140F. My oil temps increase my coolant temps with the oil = to water exchanger by 10-16F. I don't see how your water temps could be = so high with the top cowl removed. I can run several minutes with my top = cowl removed at high power setting and I really have to push it to see = temps above 180F.=20 =20 Bobby =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On = Behalf Of Chris Barber Sent: Wednesday, March 07, 2012 11:04 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Ground Cooling =20 Actually, I have done very little with the cowl on. The feed to the = radiator is from the top mounted NACA's per plans (Velocity SE). I know = PL hates NACA and I have options if these do not prove adequate, but it = seems the most elegant solution as of now. But, at this point, the = ducting would seeminlgy have little to do with cooling. I have not air = other than the fans when on the ramp. =20 The radiator is mounted perpendicular directly in front of the engine = very much like in the car and the NACA feed directly to the radiator. = The radiator is the back wall of the air chamber, air hitting it first = at a 90 degree angle and the oil cooler is the bottom/floor or the air = chamber (with ducting feeding from the NACA to the bottom mounted oil = cooler) with the sides being sealed by fiberglass walls. Ram air could = be fed through the side walls via the armpit scoops I have for intake = air and ancillary cooling of components. The fans are on the top of the = radiator cuz that is where they would fit. There are also three four = inch fans on the factory oil cooler. =20 The top of the radiator is cool to the touch right were the fans are = drawing air through. It is warm when first shut down, but cools in a = minute or so with the fans on. The rest of the system is warm/hot as = one would expect. =20 So, your coolant max is 210 but during climb out it raises 25-30 to 235 = or so degrees for a few minutes or does it hit 210 or so during climb = out and drops to 180-185 in cruse? =20 Thanks guys, this is the kind of stuff I was looking for. Keep it = coming please =20 Chris ________________________________ From: Rotary motors in aircraft [flyrotary@lancaironline.net] on behalf = of Bobby J. Hughes [bhughes@qnsi.net] Sent: Wednesday, March 07, 2012 10:24 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Ground Cooling Chris, =20 How much better is your ground cooling with your top cowl removed?=20 =20 I have two fans pulling air through the heat exchanger and the radiator = area where the fans are is cool to the touch with the fans on right after = shutdown.=20 Are you sure the coolant is actually flowing through the radiator core = and not taking a shortcut? It takes several minutes for my radiator to = cool down enough to touch after shutdown. I would remove the thermostat = and plug the hole between the inlet and outlet. Drill a small bleed in = the plug to allow trapped air to pass. I think I used a #30 drill. For = my renesis I was able to tap the thermostat hole and install a standard = size threaded plug. Don't remember the details but I measured the = opening and selected a tap and plug that would best work with the = existing hole size. Could have been a =BD NPT. =20 =20 I also added a Schrader valve at the highest point of the pump outlet on = the engine. When all the trapped air is removed my radiator outlet warms = up confirming coolant flow. It usually takes two or three short runs to = bleed all the air and top off the coolant. I also monitor all heat = exchanger inlet and outlet temps with CHT wires clamped where needed. = This is not only helpful in flight but also when changing coolant. I can = easily tell from the cockpit if coolant is flowing through the heat = exchanger or I need to shut down and purge more air.=20 =20 I always anticipate a 25-30F coolant rise for takeoff and climb. My max = coolant temp is set at 210F but I rarely see over200F. =20 Bobby=20 =20 =20 =20 =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On = Behalf Of Chris Barber Sent: Wednesday, March 07, 2012 7:35 AM To: Rotary motors in aircraft Subject: [FlyRotary] Ground Cooling =20 I am cross-posting this from Paul's site. I should have posted here = first. I think I was just reading that list when I wrote it. =20 The initial response I do not think really addressed the issue asked = about but Lee Hanover did post some info that I followed through with = last night. Not sure of any measurable difference yet, but at least it = provides something proactive. I know some of us monitor both list so = sorry for the redundancy. =20 As I state in the post, I do not know how much ducting effects a pusher = when stationary. My buddy with a soob on his RV-7 gets quite a bit of = cooling from the prop.....being up front. =20 =20 Since, as was just mentioned, the list has been quit enough to have us = question if it were still up, perhaps this will jump start us a bit..... =20 Chris =20 Paul, What kind of temps should we be seeing on the ground? On Page 19 of your book (I was one of your first purchasers) it mentions even the P5 1had trouble on taxi and climb out. No comparison between mine and a P-51, but similar concern. I am currently re-reading it again to gather potential new insight. Funny, I understand much more of it now than when I got it :-). Yes, I understand that it is in flight that is our main concern, but it I heat up too much do to a long taxi or long hold or while doing run ups, it may prevent my flying for a while...especially if I trash an engine. I have this horrible image of me in the pattern with steam trailing behind my plane...yes, better than smoke, but still not good. I am currently doing my (hopefully final) high rpm engine runs before attempting first flight. I have scheduled transitional training with Velocity, Inc in Florida for early April. While I seem to maintain reasonable temps while at idle, even higher idle of around 2000 rpm, even though I seem to run hotter than I use to (may be the addition of the turbo since nothing else major was changed), when I run up the engine WITHOUT any air from the prop in my pusher aircraft, my temps soar very quickly, perhaps a minute or so before I idle back to bring temps down. From the 185/190 to past 220, sometimes a little more for a couple of seconds when I throttle back. I hate going this hot and have only done so to test full power twice, but do now wish to trash another set of seals or worse. I spoke with another pusher 13b pusher jockeythat says he has the same until he gets moving. I have not had any boil over though...yet...? I don't know if this is a bigger problem in pushers since it does not have the big fan up front pushing air into the system or not. I know a lot changes when you go faster and that is where I am thinking some of the ducting "magic" comes more into play, but since I am currently limited to a run up area, after a few minute taxi at a controlled airport in Houston, I am very stationary and yesterday it was "only" 80 degrees out and I had to sit and cool down before I ventured to taxi back to the hangar. My 13b, with water channel mods, street ported by Mazdatrix, a turbo with low boost for testing (3 lbs) as much for muffler use as any (yes, it made a heck of a difference). My prop is an in-flight adjustable 68 inch three blade, with 45 degree full fine IVO. The coolant heat exchanger is between the size of John Slade and Dave Leonard sat 22 x 19 x 3 =3D 1254 or a frontal area of 418. I have two fans pulling air through the heat exchanger and the radiator area where the fans are is cool to the touch with the fans on right after shutdown. I am running up to about 6200 rpm static with about 32 inch manifold pressure. I am using Royal Purple synthetic oil. 50% water to 50% coolant with some Water Wetter added. I have a coolant line from the port on the top of the engine to a pressure tank, then to the recovery tank as illustrated on page 39 to help relieve trapped air. Is there a conventional wisdom other than this to "burp" the air out of the system. I have actully lifted the nose to try to shake air pockets out. Again, I am curious as to your and others experiences on the ground and taxi as this is before most of the ducting, diffusing and wedging comes into play. As always, your/y'all's input is appreciated. Thanks (in advance) Chris Houston Send me some pictures of what your rad ducting looks like. I think you are more likely to have problems on climb out. Pick a cool day to do testing and climb out at the highest speed that is safe. Keep the climb angle shallow until you see how well it works. What are the rad core dimensions? Bulents installation worked pretty good but he did away with the early turbo. Air outlets are important as well. The prop will suck air flowing over the outlets. Air is somewhat like molasses in that it tends to stick to everything including itself. His wedge diffuser could have been a bit better. 10 quarts in the oil pan is good as it takes longer to heat up 10 quarts rather than only five. My O-470 230 HP engine has 12. Paul Lamar Do you have the Mazda thermostat installed? If not, have you plugged the bypass hole to prevent circulation through it? The engine will overheat = if this is left out. Dale Davies Try cutting that antifreeze back to 10% just to help with the boiling = point. Try a Stant 22 pound lever cap. Dump the coolant and save it. Refill with just distilled water and Water Wetter or a teaspoon full of Dawn dishwashing detergent. Run the system to temp a few times including = some revs to clean things out. Then Dump that mixture and refill with 10% coolant and = distilled water and Water Wetter. The 50/50 idea is for winter time and selling lots of Prestone. The best coolant is distilled water. Lynn E. Hanover My radiator is 22 x 19 x 3 =3D 1254. Yes. I need to fly to verifying = ducting. However, I am currently focusing on ground temps for start up, getting to the = active and run ups. Not sure how ducting does much at this stage with the fan in the = back. Yes. I am running a thermostat. Honestly, I am uncertain on which = passage to seal off in order to remove the thermostat. I would hate to choose wrong. Directions/illustrations here would be appreciated. I must conceded, = pulling the water pump housing is not an appealing thought right now regardless of = how good I have now gotten at such things on the rotary. I think I may drain the coolant tonight. I will go the distilled with = some warer wetter i think Unless the earth tilts its axis, Houston is not in = direct peril from cold. Chris Houston =20 ------_=_NextPart_001_01CCFC86.ACD0DA2D Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Chris,

 

My personal coolant limit is 210F. I sometimes see 200F on climb out. = I anticipate a 25-30F rise as part of my go/no-go decision. My coolant = after normal taxi has been 170-175F. Cruise is usually 170-180F = depending on OAT and power settings. Long flights at high altitude I can = see as low as 140F. My oil temps increase my coolant temps with the oil = to water exchanger by 10-16F. I don’t see how your water temps = could be so high with the top cowl removed. I can run several minutes = with my top cowl removed at high power setting and I really have to push = it to see temps above 180F.

 

Bobby

 

From:= = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On = Behalf Of Chris Barber
Sent: Wednesday, March 07, 2012 = 11:04 AM
To: Rotary motors in aircraft
Subject: = [FlyRotary] Re: Ground Cooling

 

= Actually, I have done very little with the cowl on.  The feed to = the radiator is from the top mounted NACA's per plans (Velocity = SE). I know PL hates NACA and I have options if these do = not prove adequate, but it seems the most elegant solution as of = now.  But, at this point, the ducting would seeminlgy = have little to do with cooling.  I have not air other than the fans = when on the ramp.

=  

= The radiator is mounted perpendicular directly in front of the engine = very much like in the car and the NACA feed directly to the = radiator.  The radiator is the back wall of the air chamber, air = hitting it first at a 90 degree angle and the oil cooler is the = bottom/floor or the air chamber (with ducting feeding from = the NACA to the bottom mounted oil cooler) with the sides = being sealed by fiberglass walls.  Ram air could be fed through the = side walls via the armpit scoops I have for intake air and ancillary = cooling of components.  The fans are on the top of the = radiator cuz that is where they would fit. There are also three = four inch fans on the factory oil cooler.

=  

= The top of the radiator is cool to the touch right were the fans are = drawing air through.  It is warm when first shut down, but cools in = a minute or so with the fans on.  The rest of the system is = warm/hot as one would expect.

=  

= So, your coolant max is 210 but during climb out it raises 25-30 to = 235  or so degrees for a few minutes or does it hit 210 = or so during climb out and drops to 180-185 in = cruse?

=  

= Thanks guys, this is the kind of stuff I was looking for.  Keep it = coming please

=  

= Chris

=

= From:= Rotary motors in aircraft [flyrotary@lancaironline.net] on behalf of = Bobby J. Hughes [bhughes@qnsi.net]
Sent: Wednesday, March 07, = 2012 10:24 AM
To: Rotary motors in aircraft
Subject: = [FlyRotary] Re: Ground Cooling

Chris,

 

How much better is your ground cooling with your top cowl removed? =

 

= I have two fans pulling air through the heat exchanger and the radiator = area
where the fans are is cool to the touch with the fans on right = after shutdown.

Are you sure the coolant is actually flowing through the radiator = core and not taking a shortcut? It takes several minutes for my radiator = to cool down enough to touch after shutdown.  I would remove the = thermostat and plug the hole between the inlet and outlet. Drill a small = bleed in the plug to allow trapped air to pass. I think I used a #30 = drill. For my renesis I was able to tap the thermostat hole and install = a standard size threaded plug. Don’t remember the details but I = measured the opening and selected a tap and plug that would best work = with the existing hole size. Could have been a =BD NPT.  =

 

I also added a Schrader valve at the highest point of the pump outlet = on the engine. When all the trapped air is removed my radiator outlet = warms up confirming coolant flow. It usually takes two or three short = runs to bleed all the air and top off the coolant.  I also monitor = all heat exchanger inlet and outlet temps with CHT wires clamped where = needed.  This is not only helpful in flight but also when changing = coolant. I can easily tell from the cockpit if coolant is flowing = through the heat exchanger or I need to shut down and purge more air. =

 

I always anticipate a 25-30F coolant rise for takeoff and climb. My = max coolant temp is set at 210F but I rarely see over200F.

 

Bobby

 

 

 

 

 

= From:= Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf = Of Chris Barber
Sent: Wednesday, March 07, 2012 7:35 = AM
To: Rotary motors in aircraft
Subject: = [FlyRotary] Ground Cooling

 

= I am cross-posting this from Paul's site.  I should have posted = here first.  I think I was just reading that list when I wrote = it.

 

= The initial response I do not think really addressed the issue = asked about but Lee Hanover did post some info that I followed = through with last night.  Not sure of any measurable difference = yet, but at least it provides something proactive. I know some of us = monitor both list so sorry for the redundancy.

 

= As I state in the post, I do not know how much ducting effects a pusher = when stationary.  My buddy with a soob on his RV-7 gets quite = a bit of cooling from the prop.....being up front. 

 

= Since, as was just mentioned, the list has been quit enough to have us = question if it were still up, perhaps this will jump start us a = bit.....

 

= Chris

 

= Paul,

What kind of temps should we be seeing on the ground?  = On Page 19 of
your book (I was one of your first purchasers) it = mentions even the
P5 1had trouble on taxi and climb out.  = No comparison between mine
and a P-51, but similar concern.  I = am currently re-reading it again
to gather potential new = insight.  Funny, I understand much more of
it now than when I = got it :-).  Yes, I understand that it is in
flight that is our = main concern, but it I heat up too much do to a
long taxi or long = hold or while doing run ups, it may prevent my
flying for a = while...especially if I trash an engine.  I have this
horrible = image of me in the pattern with steam trailing behind my
plane...yes, = better than smoke, but still not good.

I am currently doing my = (hopefully final) high rpm engine runs
before attempting first = flight.  I have scheduled transitional
training with Velocity, = Inc in Florida for early April.

While I seem to maintain = reasonable temps while at idle, even higher
idle of around 2000 rpm, = even though I seem to run hotter than I use
to (may be the addition = of the turbo since nothing else major was
changed), when I run up the = engine WITHOUT any air from the prop in
my pusher aircraft, my temps = soar very quickly, perhaps a minute or
so before I idle back to bring = temps down. From the 185/190 to past
220, sometimes a little more for = a couple of seconds when I throttle
back.  I hate going this hot = and have only done so to test full
power twice, but do now wish to = trash another set of seals or worse.
  I spoke with another = pusher 13b  pusher jockeythat says he has the
same = until he gets moving.  I have not had any boil = over
though...yet...?  I don't know if this is a bigger problem = in
pushers since it does not have the big fan up front pushing air = into
the system or not.

I know a lot changes when you go = faster and that is where I am
thinking some of the ducting = "magic" comes more into play, but since
I am currently = limited to a run up area, after a few minute taxi at
a controlled = airport in Houston, I am very stationary and yesterday
it was = "only" 80 degrees out and I had to sit and cool down before = I
ventured to taxi back to the hangar.

My 13b, with water = channel mods, street ported by Mazdatrix, a turbo
with low boost for = testing (3 lbs) as much for muffler use as any
(yes, it made a heck = of a difference).  My prop is an in-flight
adjustable 68 inch = three blade, with 45 degree full fine IVO.  The
coolant heat = exchanger is between the size of John Slade and Dave
Leonard sat 22 x = 19 x 3 =3D 1254 or a frontal area of 418.  I have two
fans = pulling air through the heat exchanger and the radiator area
where = the fans are is cool to the touch with the fans on right = after
shutdown.

I am running up to about 6200 rpm static with = about 32 inch manifold
pressure. I am using Royal Purple synthetic = oil. 50% water to 50%
coolant with some Water Wetter added.

I = have a coolant line from the port on the top of the engine to = a
pressure tank, then to the recovery tank as illustrated on page = 39
to help relieve trapped air.  Is there a conventional wisdom = other
than this to "burp" the air out of the system.  = I have actully
lifted the nose to try to shake air pockets = out.

Again, I am curious as to your and others experiences on the = ground
and taxi as this is before most of the ducting, diffusing = and
wedging comes into play.

As always, your/y'all's input is = appreciated.

Thanks (in = advance)

Chris

Houston

Send me some pictures of = what your rad ducting looks like.
I think you are more likely to = have problems on climb out. Pick a
cool day to do testing and climb = out at the highest speed that is
safe. Keep the climb angle shallow = until you see how well it works.
What are the rad core = dimensions?

Bulents installation worked pretty good but he = did away with the
early turbo.

Air outlets are important as = well. The prop will suck air flowing
over the outlets. Air is = somewhat like molasses in that it tends to
stick to everything = including itself.

His wedge diffuser could have been a bit = better.

10 quarts in the oil pan is good as it takes longer to = heat up 10
quarts rather than only five. My O-470 230 HP engine has = 12.

Paul Lamar

Do you have the Mazda thermostat installed? = If not, have you plugged the
bypass hole to prevent circulation = through it? The engine will overheat if
this is left out.

Dale = Davies

Try cutting that antifreeze back to 10% just to help with = the boiling point. Try a
Stant 22 pound lever cap. Dump the = coolant and save it.

Refill with just distilled water and Water = Wetter or a teaspoon full of
Dawn dishwashing detergent. Run the = system to temp a few times including some revs to
clean things out. = Then Dump that mixture and refill with 10% coolant and = distilled
water and Water Wetter.
The 50/50 idea is for winter = time and selling lots of Prestone.
The best coolant is distilled = water.

Lynn E. Hanover


My radiator is 22 x 19 x 3 =3D = 1254.  Yes. I need to fly to verifying ducting. However,
I am = currently focusing on ground temps for start up, getting to the active = and run
ups. Not sure how ducting does much at this stage with the = fan in the back.

Yes. I am running a thermostat. Honestly, I am = uncertain on which passage to seal off
in order to remove the = thermostat. I would hate to choose wrong.
Directions/illustrations = here would be appreciated. I must conceded, pulling the
water pump = housing is not an appealing thought right now regardless of how good = I
have now gotten at such things on the rotary.

I think I may = drain the coolant tonight. I will go the distilled with some = warer
wetter i think  Unless the earth tilts its axis, = Houston is not in direct peril = from
cold.

Chris

Houston

 

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