190V-18

[oakranger]

Try to find photos of this particular 190. Interesting information behind the reason of it, but i guess it was only experimental. Any input?

[beau32]

The FW 190 V18 was designed and built as a prototype for the high-altitude FW 190 C, and in V18/U1 form it had the DB 603 A engine driving a four-bladed propeller. The FW 190 C was a projected high-altitude fighter that never came to fruition; even so five prototypes were completed, the FW 190 V18, V29, V30, V32 and V33. Each of these aircraft had DB 603 inline engines, annular radiators, Hirth 9-2281 turbochargers and four-bladed propellers. The FW 190 V18 was coded CF + OY and received a white outline Balkenkreuz and Hakenkreuz. By 1944 the project had been halted by technical problems and opposition to use of the DB 603 (which was needed for other aircraft types).

V18 (W.Nr 0040) was previously used in the Hohenjager programme, and with its huge belly mounted turbo-supercharger, was nicknamed "Kangaroo".

This project came to nothing, and it was decided to convert the airframe to Ta 152H standard as part of the H-series prototype "family", but it only left the prototype shop as series production was starting, and was not used in any testing. It was used instead for pilot familiarisation, and a new wooden tail was fitted after damage sustained in a take off crash on on 23rd December 1944. (Incidentally, Ta 152H series production started after the prototypes had made just 30 hours and 52 minutes of test flights in total!)



A very intresting looking Fw-190. The bottom reminds me of the Mustang, wonder if that is where they got the Idea? Most info found through out the internet.

[oakranger]

A very intresting looking Fw-190. The bottom reminds me of the Mustang, wonder if that is where they got the Idea? Most info found through out the internet.

I was thinking of the same thing when i first saw the image. It sure looks like it.  Great job on finding pics too.   

[Krusty]

The underside cooler is more like that of the 109H project. Large scoops were not unique to the P-51. Even the Hurricane and other 1930s designs had them.

The radiator was still around the nose (cowl flaps and all), and what you are looking at is the cooler for the turbocharger.

The system had many flaws, also relating to the reliability and cost of such a system. I believe they also had major heat issues causing failures in the ducting (the pipes you see running back) as it required special types of metal.

Overall it was found to be too heavy, too draggy, too unreliable, and too costly, considering that Germany was already developing engines with 3 stage superchargers that did the job just as well (theoretically -- these also had problems but usually on the highest third stage) or even better.

The focus was maintained on additives (MW50, GM-1, etc), higher geared engines (Jumo engine on Ta152 for example) and simply more powerful engines (DB603G which practically never manifested, for example)

[oakranger]

The underside cooler is more like that of the 109H project. Large scoops were not unique to the P-51. Even the Hurricane and other 1930s designs had them.

The radiator was still around the nose (cowl flaps and all), and what you are looking at is the cooler for the turbocharger.

The system had many flaws, also relating to the reliability and cost of such a system. I believe they also had major heat issues causing failures in the ducting (the pipes you see running back) as it required special types of metal.

Overall it was found to be too heavy, too draggy, too unreliable, and too costly, considering that Germany was already developing engines with 3 stage superchargers that did the job just as well (theoretically -- these also had problems but usually on the highest third stage) or even better.

The focus was maintained on additives (MW50, GM-1, etc), higher geared engines (Jumo engine on Ta152 for example) and simply more powerful engines (DB603G which practically never manifested, for example)

Reason why they took the Ta-152. 

[Krusty]

Well the Ta152 was just one evolution of the design. There were other planes and they were also using higher-geared engines and GM-1 boost and whatnot. Ju-88S for example, relied on GM-1 for its high alt speed runs. There were also the jets and the rocket powered planes, as well. The Turbosupercharger just didn't fit with Germany at the time.

Look at the DB603, for example. On the same engine you have the one model with a FTH of about 19K with a single stage charger, and about 25K with a double stage charger. Swap out that charger to a different model and you get potentially over 30K FTH on the 603L/N (not sure if those saw the light of day outside of testing)

You could achieve the same results with existing technology.

[dirtdart]

What I find quite extraordinary is the evolution of the cooling systems in response to the higher altitudes.  To acheive these higher level flights, the cooling system had to be pressurized (closer to armstongs line...).

[oakranger]

What I find quite extraordinary is the evolution of the cooling systems in response to the higher altitudes.  To acheive these higher level flights, the cooling system had to be pressurized (closer to armstongs line...).

When was the cooling system pressurized? Who accomplished this?

[MAINER]

Whats the point of the exhaust pipe being so long?

[Krusty]

It's not an exhaust pipe. It's taking the exhaust pressure and routing it through a turbosupercharger for high altitude performance.

[dirtdart]

The germans did on the TA-152.  The cockpit and cooling system was pressurized.  Water boils at 212 at sea level, at 10k the temperature is 193 degrees.  20K, 182.  The boiling point is relative to atmospheric pressure as are other things.  To acheive adequate cooling, the system had to be pressurized. 

[Krusty]

By its very nature, liquid cooling is a closed, pressurized, thing.

Your cooling system isn't affected by air pressure because it's maintained inside metal pipes. The pipes provide the pressure.


Think of it this way: When your car overheats do you open the radiator cap? Hint: Better stock up on burn cream if you try it!

We're not talking calm water boiling away due to a drop in pressure. Nor was water even used for most liquid cooling on these planes.

[dirtdart]

When I get home I will dig through my stuff.  One of the issue with high altitude flight and liquid cooled engines is the inability to cool water as a result of its boiling point decreasing in relationship to altitude.    http://en.wikipedia.org/wiki/Junkers_Jumo_213 this is the wiki link, but I do have some books at home that get a bit more into the idea, one is  Willy Messerschmitt, Pioneer of Aviation Design by Ebert, Kaiser, and Peters.  IIRC they have some discussion on cooling challenges at altitude.  More to follow.

[dirtdart]

By its very nature, liquid cooling is a closed, pressurized, thing.

Your cooling system isn't affected by air pressure because it's maintained inside metal pipes. The pipes provide the pressure.


Think of it this way: When your car overheats do you open the radiator cap? Hint: Better stock up on burn cream if you try it!

We're not talking calm water boiling away due to a drop in pressure. Nor was water even used for most liquid cooling on these planes.

Your car runs at say, 230 degrees, why, because the gas is not allowed to expand and the fluid actually boil.  So, yes it is "pressurized" in a way.  But this is a car in the year 2011.  The solutions developed to address this very problem were quite interesting to me from an engineering standpoint.  Having tubes, radiators, blocks, gaskets, all designed to take into account the stresses of maintaining a heated fluid in its liquid state. 

[dirtdart]

Got home, nope not in the ebert book, the piece I remember seeing high altitude discussion, stemmed from the the use of MW-50 to alt, then switching to GM-1.  Had something to do with engine cooling, that is why it was stuck in my mind at the time.  

There is much more to this, air pressure having a lot to do with the ability of a heat exchanger to "exchange heat".  Lots of stuff is out there on air cooled engines, but I am having a hard time find specifics on high altitude radiator design, inlet design, and exhaust design.  The radiator has to be larger because although colder, the atmosphere is not as efficient at heat transfer (giant math stuff, nearly over my head)

http://digital.library.unt.edu/ark:/67531/metadc61946/m1/10/

Bear in mind this paper discusses air cooled engines at altitude, but the concept of heat transfer also will apply to liquid cooling if you substitute the cylinder head design and interior cowl design for radiator design.  

Part of making massive power is massive cooling.  There are drag engines that make 7000HP out of less than 700 Cu in, but only for 4 seconds or so.  Making 1000HP for hours, now that is cool, literally.