peanut gallery comment: if one goal is use the rad/oil cooler outputs for
cabin heat, would it not be better to put the flap on the outlet (instead
of the inlet)? this way the slower (and thus hotter)
behind-the-radiator-air would be forced into the cabin heat duct. There
would also be higher pressure on the heater duct over the inlet-size
reduction method.
no? (I was also planning on using radiator heat some day.... when i get my
parts into formation)
Cheers,
Pete
A239
On Mon, Dec 3, 2012 at 1:59 PM, Gary Leinberger <
Gary.Leinberger@millersville.edu> wrote:
> Gary.Leinberger@millersville.edu>
>
> I am working with Bud on my cooling problem and have his cooling flap
> installed - think this is the ticket along with the oil thermostat - which
> I haven't installed yet. I have been experimenting with various tape
> combinations - my results are tentative and require some more careful data
> gathering.
>
> It appears that the oil temp is not much influenced by the amount of tape
> covering the radiator, and is somewhat affected by the outside temperature.
> In my plane, the cooling is too good and the plane runs too cool. This is
> an engine efficiency problem, but more importantly in the north, a heater
> problem. The amount of tape on the oil radiator doesn't seem to affect the
> heater output. (Duh, it is lower than the water radiator and much lower
> than the heater intake.) Higher oil temperatures do not seem to affect the
> water temperatures, at least in the range I have experimented with.
>
> The water temperature is greatly affected by the amount of tape covering
> the water radiator. At the margin a small change in tape will greatly
> affect the CHT. For example, going from covering 1/2 the radiator to 3/4 of
> the radiator made the CHT climb from 170 to 270 and resulted in boiling
> over the radiator (lost about a cup.) When in cruise in this config (1/2
> tape to 3/4 tape) the temps went from 170 to 180 or so. The heater output
> was better than when running at 160 with no tape. The high sensitivity in
> the temps due to the changes in airflow at the margin suggests that a
> permanent (non-cockpit controllable blocking of the radiator) is not a good
> idea.
>
> I have put a little sheet metal box around the top right rear of the water
> radiator and that is doing a better job of directing the air. It is
> however, not yet sufficient, particularly for she that must be obeyed. I
> think Bud's idea is the way to go with a flap, but we put on a wimpy cable
> (which also doesn't hold open except with a vise grip)and the flap may be
> too weak - the result being when I pull the flap shut the flap doesn't
> close well - resulting in little no decrease in airflow - what may be
> happening is that the air flow is just speeding up and I see no different
> in the CHT with the flap closed or open.
>
> On my to do list:
>
> Need to move coolant temp to show on EIS - presently I don't display water
> temp on the EIS or HX - only shows when I get a warning.
>
> I need better data. On the day I tested I either had strange inversion
> with OAT at altitude higher than on ground, or engine temp affected OAT
> sensor in the carb box.
>
> I may have to seal up the flap better with cowling rubber to cut down the
> air flow.
>
> I must repeat to myself it is called an experimental aircraft for a reason.
>
>
> Gary Leinberger
> A237
> N388SG
> gleinberger@millersville.edu
> Lancaster, Pa.
> USA
>
>
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