On 08/29/2010 08:28 PM, Bud Yerly wrote:
> One note though on ram air to the engine, please see the Rotax
> specifications for that need. It is hard for me not to do as the
> manufacturer recommends.
I do that to. I have naca ducts in the top cowling. This probably is
more efficient than the Europa round inlets, while it consumes less air
at the same time. I have never calculated how large (small?) the air
inlets need to be to conform to the Rotax specifications. Did you?
Commercial aircraft with the Rotax 914 have even less cowling ventilation.
The main point I want to make is that the solution for the cooling
problem needs to be sought by optimizing the cooling of the water and
oil, and not so much by cooling the engine core. It collects
surprisingly little heat once the water cooling and oil cooling are
working ok. In fact, I can't think of many reasons why the engine block
would heat up. Combustion takes place in the cylinder heads, and the oil
takes away all friction heat. The engine block itself is just a holder
for the various components and has no reason to heat up by itself.
> We will all be interested in your data...
I will keep you updated, although it will take a while before this is
finished and tested in both winter and summer temperatures.
Frans
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