agree with all you=C2- say, however: I used to get exhaust gas in cabin w
ithout it, it probably got in via the flap slots. There must be a significa
nt drag penalty from the exhaust plume squirting out vertical to the airflo
w.=0A=0AGraham=0A=0A=0A=0A________________________________=0A From: Paul Mc
Allister <paul.the.aviator@gmail.com>=0ATo: europa-list@matronics.com =0ASe
nt: Saturday, 23 June 2012, 14:44=0ASubject: Re: Europa-List: Re: Contact d
etail & Help=0A =0A=0AHello Graham,=0A=0AFrans has attempted this with his
design, but for a mono wheel there is a very real chance of CO entering the
airplane through the tunnel.=0A=0AExhaust augmentation / extraction makes
a whole range of issues go away.=C2- Ground cooling gets better the faste
r the engine runs, and as I understand it from the Long EZ guys, you no lon
ger need to diffuse the inlet airstream.=0A=0AAlas, I am with Bud on this..
.. time for tinkering is long over.=C2- I would guess with research and b
uilding that Frans and I have spent many hundreds of hours and its time to
go flying :)=0A=0ACheers, Paul=0A=0A=0AOn Sat, Jun 23, 2012 at 5:44 AM, GRA
HAM SINGLETON <grahamsingleton@btinternet.com> wrote:=0A=0APaul=0A>you know
I can't resist temptation! I suspect that a bit of work re exdhaust extrac
tion might=0A>be profitable, it seems to work well on Long EZs, hoping to v
erify with flight testing in the next month.=0A>Graham=0A>=0A>=0A>=0A>_____
___________________________=0A> From: Paul McAllister <paul.the.aviator@gma
il.com>=0A>To: europa-list@matronics.com =0A>Sent: Wednesday, 20 June 2012,
17:32=0A>=0A>Subject: Re: Europa-List: Re: Contact detail & Help=0A> =0A>
=0A>Ha ha.... I wondered who was going to be first out of the=0Acloset, me
or Fran=99s. =C2-Fran=99s and I have=0Abeen collaborating on
a journey of discovery for the last couple of years.=C2- =0A>I have been
reluctant to share what I have been doing,=0Amostly because up until now I
have only been able to tell everyone what doesn't=0Awork! Both Fran's and I
can share funny stories of tuft test showing air flow=0Aout where it shoul
d be flowing in, some take offs where we couldn't get back on=0Athe ground
quick enough due overheating and lots of work and re work.=0A>For me, I am
still works in progress, but over the next=0Awinter I plan on a fourth iter
ation over next winter which will be a similar=0Adesign to Fran=99s.
If I can persuade my friend Graham Singleton to come and=0Avisit, it might
even a new carbon fiber cowling :)=0A>=0A>=0A>=C2-=0A>At a high level the
sources of design material we used were:=0A>* =C2- =C2- =C2- =C2
-Kays & London wedge diffuser=0A>* =C2- =C2- =C2- =C2-=C2-Ku
chemann & Weber trumpet diffuser=0A>* =C2- =C2- =C2- =C2-=C2-C
ooling design notes from the Central States=0ACanard Group=0A>* =C2-
=C2- =C2- =C2-=C2-Taper diffuser design from the Canard group=0A>
* =C2- =C2- =C2- =C2-=C2-Oil Streaking presentations from the
Central=0AStates Canard Group=0A>* =C2- =C2- =C2- =C2-=C2-Thin
k Vs. think radiator notes from Rotary=0AEngine forums.=0A>* =C2- =C2
- =C2- =C2-=C2-Cooling Vs flow data from Rotax and Laminova=0A>=C2
-=0A>Our design criteria was:=0A>Cooling that works in all phases of oper
ation:=0A>* =C2- =C2- =C2- =C2-Ground=0A>* =C2- =C2- =C2
- =C2-Climb=0A>* =C2- =C2- =C2- =C2-Cruise=0A>Operates over
a range of -5c to 40c=0A>Offers the lowest drag possible=0A>=C2-=0A>This
ultimately dictated a few design solutions:=0A>=0A>=0A>Cowl Flap. =0A>This
is the only way we could get cooling over a large speed=0Arange and ambient
temperature.=0A>=C2-=0A>Laminova liquid oil=0Aheat exchanger.=0A>In one
of the design iterations that Fran's had created he=0Ahad the oil and water
radiators separated. Although this provided plenty of oil=0Aand liquid coo
ling it caused a long cycle time to bring the oil temperature up=0Ato opera
ting temperature. The Laminova solves this problem.=C2- One problem that
Fran's and I have not been=0Aable to solve is the need for a small axillary
oil radiator.=0A>=C2-=0A>Thick Vs. Thin=0ARadiators.=0A>I was ultimately
able to make the thick radiator work with a=0AKuchemann & Weber trumpet di
ffuser, but I intend to abandon this. From our=0Aresearch we have discovere
d that 70 to 80% of the heat exchange occurs in the=0Afirst 20mm of the rad
iator.=0A>=C2-=0A>Diffused Inlets.=0A>At first glance Fran's cowl appears
to have no diffuser on=0Athe inlet side of the radiator, however it works
very well.=C2- After reading the design notes for the Kays=0A& London wed
ge diffuser our hypothesis is that because the coolant radiator=0Ais at an
angle to the relative wind it behaves like a wedge diffusers.=0A>=C2-=0A>
Other thoughts &=0Aobservations.=0A>Fran=99s has been flying a workin
g solution for nearly a year=0Aand his design can be used as is.=C2- I am
=0Adoing some experimentation with a single diffused inlet that provides th
e=0Aengine combustion air, inter cooler and the engine shroud. =C2-Given
the level of effort this has proved to=0Abe I wouldn=99t recommend an
yone copying what I have done, and it remains to be=0Aseen if it even works
.=0A>Over next winter I plan on removing the thick radiator and I=0Aexpect
that this will be a lower drag configuration over what I have.=0A>Pointing
the exhaust back is offers a lot of drag reduction.=0AI have some photograp
hs that show the exhaust plume on the old style exhaust=0Ashooting out near
ly 2 meters.=C2- For=0Amonowheel the exhaust needs to be much longer so t
hat carbon monoxide does not=0Afind its way into cabin via the tunnel. Unfo
rtunately this was complex bit of=0Astainless steel to fabricate.=0A>When m
y cowling is fully open it is the same angle as the=0Astandard cowling.=C2
- I see 8 knots=0Adifference between fully open and fully closed.=C2-
=0AThis isn't an exact comparison because when my cowl flap is open air=0Aw
ill spill around the side and I expect this would be higher drag than the o
riginal=0Acowl.=C2- I have done a number of long cross=0Acountry trips an
d for the same manifold pressure settings I am seeing about 5=0Aknots incre
ase in my cruise.=C2- I have Warp=0Adrive blades and I do not wing root f
airings so my set up is not as efficient=0Aas Fran=99s.=0A>=0A>=0A>Re
gards, Paul=0A>http://www.matronics.com/Navigator?_blank"; href="http://fo
rums.matronics.com/">http://forums.matronics.com=0A> arget="_blank">http:
//www.matronics.com/Navigator?Europa-List=0Atp://forums.matronics.com=0A_bl
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