Frans,
Do you have any photos of your cooling set up available? Thanks.
Jerry
On Oct 4, 2012, at 4:56 PM, Frans Veldman wrote:
>
> On 10/04/2012 01:34 PM, Paul McAllister wrote:
>
>> As to cooling. I have extensively modified my cooling with cowl flaps,
>> lamovia heat exchanger, diffused inlets, intercooler and internal
>> ducting. I have spent 12 months over 3 winters and countless hours on
>> this and although I am close, its still not right. I would encourage
>> you to think carefully before getting into complex modifications.
>
> Well, at least we can now tell what won't work.
>
> The main thing we found is that no matter what you try, the original
> coolant radiator is just to thick to get both a decent low drag and
> efficient air flow through it. Replace it with a thin radiator (as in
> *every* commercial Rotax application I have seen) and from there you can
> just optimize the cooling system by recycling the exit air for cowling
> and turbo cooling and applying an adjustable cowl flap for temperature
> regulation, and optimizing inlet and outlet for minimal drag. It will
> give you superb cooling and add some knots to your airspeed at the same
> time.
>
>> It you really want to get into this then don't do what I did, take a
>> look at Fran's solution, but plan on adding 6 months to your build.
>
> Thanks! Well, 6 months is a little bit exaggarated once you know how to
> do it, but of course you need to extensively modify the cowling, and
> depending on your skills and experience this will take more or less
> time. I had no prior experience in modelling and building shapes, but
> once I got the hang of it I could work pretty fast. Before I got it
> right I built a dozen or so diffusing air inlets (in fruitless attempts
> to get sufficient airflow through the thick radiator). The end result
> with a thin radiator in line with the cowling belly is surprisingly
> easy, much easier to build than all the carefully calculated and shaped
> diffusers. Take a look at the Rotax equipped Diamond airplanes (super
> Dimona, Katana) to get some inspiration.
> I used a Laminova heat exchanger so I only had to care about cooling of
> the coolant.
>
> Frans
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