I recall that in 1995 I asked the late Richard Cabrinha why he had changed
---From a chin intake to a pair of Lo-Presti style circular intakes on his Free
Spirit Mark II, for cooling a Continental IO 360, and he replied "because
they work!" He told me that if the diameter were too large then there would
be a reverse flow, spilling air out round the circumference of each intake.
He refined the size by putting some oil around each rim and doing a quick
circuit: inspection on landing showed whether the oil film had spread
inwards or migrated outwards, and he would then the repeat the test with
different diameters accordingly.
For those on HTML, here is a picture of the final result:
It may not have been the most scientific way of finding the right size, but
he claimed that it worked. I have no information on the distribution of air
and temperature levels for the six cylinders. He did however incorporate
cowl flaps, one on each side at the rear of the cowling (the starboard one
is visible in the picture), which he said he would like to eliminate in due
course to simplify the design with a fixed outlet area.
Best regards
Mike
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Gilles Thesee
Sent: 02 October 2007 22:22
Subject: Re: Europa-List: Jab cooling
<Gilles.Thesee@ac-grenoble.fr>
<grahamsingleton@btinternet.com>
> I wonder if your turbulator is helping keep the flow attached over the
> whole of the outside of the cowl? That might reduce the pressure
> around the outlet at the back and that is what is important as we all
> know but can't quite understand (how to make it better I mean)
> In flight the flow over the cowl will be quite assymetric
> Thoughts Gilles?
Graham, John and all,
A little busy at the moment, so I may have missed some detail on John's
setup. I'm naturally much interested in any successful engine installation.
John, did you provide a link to your engine installation ? Sorry if I
missed the obvious.
Please continue to give info,
Best regards,
--
Gilles
http://contrails.free.fr
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