Mailing List flyrotary@lancaironline.net Message #15227
From: Leon <peon@pacific.net.au>
Subject: For Al Geitzen: Stagnant Oil was Re: [FlyRotary] Re: water cooled matrix in the oil pan
Date: Sat, 15 Jan 2005 13:27:19 +1100
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Hey Al,
 
How do you come to the conclusion that the oil is "stagnant in the pan".  What difference does the presence of a heat exchanger,  be it a full tote odds custom unit,  or a just a series of tubes in the pan,  have on oil flow?? Sure,  the oil may be a little slow flowing through the fins when it's cold,  but as the oil warms up,  this goes away.  But,  y'see,  the trick is to make the heat exchanger unit out of the correct core material.  Obviously,  one doesn't use oil cooler core or radiator core (or an evap core!!)!  Something like an auto tranny cooler is more the G-O ...  nice big flat widely spaced fins ... on edge to the oil flow ... maaaaaate ....
 
So I'm flummoxed as to how the oil can be "stagnant".   The oil still gushes out of the front,  centre & rear housing galleries,  flows over the heat exchanger tubes/fins,  and the oil pick-up removes exactly the same amount at the same rate,  forcing it into the oil galleries of the engine,  where it then gushes out of the front,  centre & rear housing galleries,  flows over the heat exchanger,  and the oil pick-up removes exactly the same amount at the same rate,  forcing it into the oil galleries of the engine ... Ad Infinitum.
 
But I've just said basically what Mike Wynnn just posted.  Hmmmmmmmm ...  Two soldiers out of step together .... better have a talk to the drum major!
 
Cheers,
 
Leon
 
P.S.
 
To make it work properly,  the heat exchanger must be fed COLD water from the pressure side of the pump,  not the heater outlet at the back of the block (but we already HAD that conversation about why nobody could get the Factory Mazda oil/water heat exchangers to  work, ... didn't we ... ??)
 
 
 
 
----- Original Message -----
From: Al Gietzen
Sent: Saturday, January 15, 2005 2:32 AM
Subject: [FlyRotary] Re: water cooled matrix in the oil pan

I was reading through some of the old postings and came across Leon's post

in which he suggested putting a water cooled matrix in a modified oil pan

(sump).  This seems to have a lot going for it.  The posting is #1188.  Of

course there are minor issues like not stuffing the dipstick through the

cooler matrix and making sure the oil pick up goes to the right place, but

nothing insurmountable.

 

There were no follow up postings and yet it seemed quite a decent idea.

What am I missing (apart from pictures of wombats and/or nude moose).

 

The problem with this is that the oil is essentially stagnant in the pan; therefore very poor heat transfer characteristics.

 

Al

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