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GazzaMataz
01-01-2005, 09:07 AM
I am a bit confused hence this post http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Liquid-cooled engines like those in the Mustang, Spitfire and Hurricane have external radiators to cool the coolant, which have flaps on them to help the cooling process.

Air-cooled engines like those on the FW109, the Thunderbolt and the Zero are cooled by the air rushing through the engine grill and don't have radiators to cool the coolant.

Is this correct? If so why can you adjust the radiator flap settings on the air-cooled engine planes when they don't have radiators?

GazzaMataz
01-01-2005, 09:07 AM
I am a bit confused hence this post http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Liquid-cooled engines like those in the Mustang, Spitfire and Hurricane have external radiators to cool the coolant, which have flaps on them to help the cooling process.

Air-cooled engines like those on the FW109, the Thunderbolt and the Zero are cooled by the air rushing through the engine grill and don't have radiators to cool the coolant.

Is this correct? If so why can you adjust the radiator flap settings on the air-cooled engine planes when they don't have radiators?

FI_Willie
01-01-2005, 09:18 AM
The cowl flpas allowed more air to circulate past the engine in order to cool it better under high work loads. ( combat, take off, max climb rate )

Under normal flight conditions, the air cooling of the engine could over cool the engine and cause damage, so the air supply was restricted by closing the flaps.

tsisqua
01-01-2005, 09:20 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by GazzaMataz:
I am a bit confused hence this post http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Liquid-cooled engines like those in the Mustang, Spitfire and Hurricane have external radiators to cool the coolant, which have flaps on them to help the cooling process.

Air-cooled engines like those on the FW109, the Thunderbolt and the Zero are cooled by the air rushing through the engine grill and don't have radiators to cool the coolant.

Is this correct? If so why can you adjust the radiator flap settings on the air-cooled engine planes when they don't have radiators? <HR></BLOCKQUOTE>

The air cooled models did, however, have cowl flaps that allowed more or less air to enter, much as if it were water cooled, there just isn't any radiator. Also, open: more drag, closed: less drag . . . and that is the reason for not leaving them open during combat (unless you are already overheating).

Hope that helped http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif
Tsisqua

Chuck_Older
01-01-2005, 09:21 AM
Take a look at a motorcycle's engine. See the things that look like little radiators? Like fins on hot water radiators in an old house's heating system?

Those are the cylinder heads. The fins on the heads are much like the heat sink on your PC's CPU, in fact, it's the same idea

Just like the liquid cooled engine, air going through a 'radiator' on a radial or air-cooled (there were liquid cooled radials, but let's not get too complex!) transfers heat out of the radiator

So. There is a finite space under the engine cowling for an air-cooled engine. the fins on the culinder heads transfer heat to the air within that space.

What happens if the air in that space can't get out? Warmer air expands, further reducing the volume of air in there, which is now hotter and hotter. So how do you counter that? By opening up that area more. That's what the cooling doors on an air-cooled engine do- allow hotter air to escape, and allow cooler, denser air in, to draw heat from the air cooled engine

And just like a liquid cooled engine's 'radiator flaps', they disrupt the aerodynamics of the plane to a certain degree

Same principle as a liquid cooled engine's radiator flaps, really