Hi Bobby
Thanks, I had the same thought yesterday.
Introduced a further 15 in2 of airflow to cowl.
I must get on and instrument the cowl for
pressures.
Thanks Lynn.
What kind of power difference might we see
between say oil of 180F and 200F
Does oil temp also effects fuel economy?
I need to do further testing at higher airs
speeds and trying to understand the tradeoffs between
approx power/eccon cost if we were to only get down to
200F.
I had a Starmazda paper that stated that they
target 200F.
Also any feedback on how to fly the engine
would be appreciated by my test pilot friend who is doing
the testing.
He is trying to get a handle on what rpm,
map, prop pitch settings to use for the various flight
regimes.
The prop is elect variable but not
auto/constant speed.
For take off we are just winding in pitch (a
human governor) to keep RPM at ~7300 and 120KIAS climb.
Now I’m guessing that we’ll eventually
experiment with best rpm/blade pitch/map that gives best
efficiency, but before then can you guys provide any
wisdom?
What RPM might you target after initial
climb?
As always, really appreciate the feedback.
Cheers
Steve Izett
>
> The oil temp tracks the power output.
Hotter rotor means hotter oil. Not a solid connection to
water temps but some. Oil temps above 160 degrees cost
power.
> Lynn E. Hanover
>
>
> Steve,
>
> If all your exchangers dump into the
cowl then the increased flow / pressure through the
coolant exchangers may be limiting air flow through the
oil cooler.
>
> Bobby
>
> -----Original Message-----
> Sent: Sunday, November 03, 2019 3:42 PM
> To: Rotary motors in aircraft
> Subject: [FlyRotary] Re: Update on
Glasair Cooling in Phase #1
>
> Sorry Matt, I just realised I hadn’t
mentioned the actual oil temps.
> Highest in climb were 114C (237F)
settling back to 110C this is 10C higher than previous
flight?? OAT was up 4C ~7F
> I would have expected a symbiotic
relationship between oil and water temps. Lower coolant
yielding lower oil temps.
> This is troubling me, Prior to this
flight I noticed oil level down on the stick. Its always
been very consistently full with no signs of leaks etc.
(Standard Renesis pan)
> It’s running Mobile 1 and measuring the
oil entering the engine after cooler and filter.
>
> Steve
>
> >
> > Coolant looks great. Are you
running a t-stat?
> > What are the oil temps when you say
"high"? Synthetic? Weight? Oil pan or inlet temp location?
> >
> > This is my opinion, with synthetic
20W50 at oil pain temps, I'd be okay during the climb with
240F and hopefully after some air speed it drops down
under 220F.
> >
> > I do agree you might have to open
up to 100mm (4 inch) for oil cooler.
> >
> > - Matt Boiteau
> >>
> >> Hi there people
> >>
> >> Over the past month I have
updated the cooling system of the Glasair Super II RG in
order to continue our phase 1 testing.
> >>
> >> The previous setup had 540in3
two pass behind the ~20in2 unmodified right cheek inlet.
> >> We hadn’t included the left
cheek as it was so difficult to get the air across to the
right hand side diffuser.
> >> The Oil is 250in3 behind a 8in2
under spinner inlet.
> >> Initial testing was marginal
with OAT below 20C (68F)
> >> So having established that
cooling was rather marginal above 68F I went for the
planned upgrade path which included
> >> installing a secondary bike
radiator of 130in3 plumbed into the heater circuit behind
the ~15in2 left cheek inlet.
> >> The diffuser was designed to
hopefully be more efficient in a climb configuration.
> >> So the total radiators frontal
area has been increased by 50% while the air in has
increased 75%.
> >> The unknown is that being in
the heater circuit we don't know the total flow through
the secondary rad compared with the primary rad.
> >>
> >> Testing on the ground yield an
approx 15-20C drop in coolant after 30mins of 1800rpm
idle.
> >>
> >> Flight Testing Results the next
day: OAT 21C (70F)
> >> Coolant Temps max’d on climb at
93C (200F) down 15C on highest Flight 3 climb temp with a
4C higher OAT.
> >> Coolant Temps dropped to 83C
(181F) as speed got to 147 KIAS (Cruise is published as
192 KIAS but we haven’t expanded the envelope to date)
> >> I’m very pleased with this
result.
> >>
> >> Oil Temps are high. I would
much prefer them below 80C (176F)
> >> I’ll be interested to see what
oil temp does as speed rises, but my hunch is it needs
more air (increase air to oil cooler from a diameter of
77mm to 100mm)
> >>
> >> Slow Speed Tests:
> >> Vs Clean Stall is at 67 KIAS
row 2011 (Glasair claims 70 Knots at Gross)
> >> Vso Full Flap Stall is at 57
KIAS row 2062 & 2083 (Glasair claims 59 Knots at
Gross)
> >>
> >> Cheers
> >>
> >> Steve Izett
> >> Perth Western Australia
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> --
>
>
> --
>
> --
--