Hi Karel,
Thanks for your detailed reply. I look forward to seeing some more
photographs when you have recovered. I'd be interested in seeing what
yo have done on the exit side.
I was also interested to hear that you changed the radiator. If I
understand it correctly, you retained the original water cooler, but
purchased a different oil cooler, is that correct ? Could you give me
a bit more information on this ? If you happen to have a WEB site, or
some technical details, that would be helpful.
Thanks again, paul
On Tue, Jan 20, 2009 at 3:50 PM, karelvranken <karelvranken@hotmail.com> wrote:
>
> Paul,
> You don't know perhaps that I was so lucky to find an Europa builder in my
> village at ten minutes walking, without knowing him before I came back from
> Kirbymoorside with the first Kit stage. Second convenience was that we
> choose the same configuration. Mono XS, Rotax 912 ULS, Airmaster CS etc...
> My friend was already one year building and afterwards he said he was making
> the rough copy for me. So I was witness of the cooling problems he had
> before I was that far and so I made several decisions from the beginning.
> If you are aware of the fact that under the cowling airflow is submitted to
> the same aerodynamic flow rules as anywhere than you may consider the
> cowling design as very poor.
> First came the fish mouth opening. By bringing the entrance farther from the
> center of the propeller you can benefit of a greather prop wash.
> Second object were the radiators. The cubic block radiator for the coolant
> even with the gap underneath filled up wasn't a technical tour de force. I
> used a radiator with the same contents but half as thick to fill up the
> disponible section. The oil radiator stayed on its original place but
> received a thermostatic valve.
> The exhaust system was keracoated in order to exchange less heath under the
> cowling.
> Finally after studying the shape of the air entrance (courtesy to Gilles
> Thesee and others) I decided to make a kind of pitot tube profile where the
> smallest section was half the area of the radiator surface. Only outside air
> is passing trough the radiators.
> Once you have sufficient air entering all the openings in the cowling, you
> also must work on the excit. Here Terry Seaver learnt me a lot to guide the
> air out and by trial and error I made the final shape after measuring
> temperatures on different places under the cowling. Therefor I used the
> epoxy and cloth that I had reinforced by a layer of carbon/kevlar. No
> particular reason for the radiuses; let's call it personal styling.
> The results are as follows: Normal temperatures for coolant (Evans) 110C at
> sea level and 95 for oil. Note that the oil is not cooled only by the
> radiator but also by the crankcase and the reservoir, this latter placed
> behind the naca scoop. In hot summer 40C the temperatures will raise up to
> 120C for the coolant and 105C for the oil while taxiing and in TO on full
> power and climbing. Even though this is temporarily until reaching cruise
> level. If at greater altitudes the coolant will slow down a bit, the oil
> stays on 90C due to the thermostatic action.
> Now it is difficult to say: copy my installation and you will have the same
> results. With the 914 you have a different configuration and therefore I
> have no experience.
> I wish you good experimental building,
> Karel Vranken #447 F-PKRL 203 hours.
> PS I am revalidating from a surgical intervention at the right shoulder. At
> a better moment I will send you some more pic's.
>
> ----- Original Message ----- From: "Paul McAllister"
> <paul.the.aviator@gmail.com>
> To: <europa-list@matronics.com>
> Sent: Tuesday, January 20, 2009 3:36 AM
> Subject: Re: Europa-List: A question on composits
>
>
>> <paul.the.aviator@gmail.com>
>>
>> Hi Karel,
>>
>> I was wondering now that you have put a little more time on your
>> airplane are you still happy with your modification? Also, I am
>> curious about a few other things.
>>
>> - Did you do this modification from the beginning, or after you had
>> been flying for a while. If yes, do you have any before / after
>> comparisons to share.
>> - How do you find this modification works on during a long taxi on a
>> hot summers day.
>> - Is the size of the inlet the same or smaller than the original
>> Europa design. If smaller, can you give me your new square area ?
>> - It looks like your new inlet does not project as far forward as the
>> original Europa design, can you give me some measurements.
>> - Did you make your modification using Epoxy or vinyl-ester resin ?
>> - Is there any particular reason that you did not make large radius's
>> on the edges of the inlet.
>>
>> I have two problems to solve, mine over heats if I have a long taxi
>> (CHT), or if Tower has me standing at the hold short line too long.
>> The other issue is that the aircraft (914) is capable to climb at more
>> that 1000 feet per minute all the way to 10,000 ~ 12,000', however the
>> oil overheats if I do more that 500' per minute.
>>
>> If you have any more photos other that the 3 you shared on the forum,
>> I'd appreciate it if you could send them on.
>>
>> Thanks for indulging my long list of questions.
>>
>> Regards, Paul
>>
>>
>> On Thu, Jul 3, 2008 at 3:28 PM, karelvranken <karelvranken@hotmail.com>
>> wrote:
>>>
>>> Jeff,
>>> In attachment my concept of cowling and inner radiator duct.
>>> Best regards,
>>> Karel Vranken
>>
>>
>>
>>
>>
>
>
|