Scale ME-262

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Erik Snyman

Well-Known Member
Joined
Oct 9, 2019
Messages
51
VHHJR, I love what you are doing. Getting real live data out there. Can I start drawing some plans for my scale Boeing Skyfox fighter, do you think? The fans will go where the turbines on the photo is.....
Erik in Oz.

 

Erik Snyman

Well-Known Member
Joined
Oct 9, 2019
Messages
51
Hello folks

I was wondering, in line with the work vhhjr posted above, would multiple fans per hub (say 2 rows), with the foremost fan blades with lower pitch, second row with higher blade pitch, not work? Sort of like a fan compressor, the first row accelerate the air stream, for the second row to get a faster airstream intake? Just wondering...

Erik in Oz.
 

pictsidhe

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Joined
Jul 15, 2014
Messages
7,373
Location
North Carolina
If designed correctly, yes. But unless you have a huge power loading, a properly designed single row will be just fine as well as being a lot simpler and lighter.
 

vhhjr

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HBA Supporter
Joined
Jun 29, 2003
Messages
72
The blades are the hardest part of making a ducted fan. With compressor blades the twist isn't quite right and the pitch is wrong if you mount them as mounted in the jet engine. But, ya gotta start somewhere and they beat bending them up from flat stock. I suspect I could optimize the blades if I had access to an entire set of compressor blades as each row has different pitch and twist.

I did make the blade angles adjustable in the 11 inch fan and it made a big difference.

The first hub I made for the 17 inch fan mounts them in the same orientation as in the jet engine. The next task is to make an adjustable blade hub.

An alternative to a multiple row arrangement is a two rotor contra-rotating fan with the advantage of taking the swirl out of the exhaust stream. If you use a same direction, multiple rotor fan you have to have stators in between the rotating rows and the swirl is still there requiring an exit stator row.

Nothing is simple!
 

Erik Snyman

Well-Known Member
Joined
Oct 9, 2019
Messages
51
The blades are the hardest part of making a ducted fan. With compressor blades the twist isn't quite right and the pitch is wrong if you mount them as mounted in the jet engine. But, ya gotta start somewhere and they beat bending them up from flat stock. I suspect I could optimize the blades if I had access to an entire set of compressor blades as each row has different pitch and twist.

I did make the blade angles adjustable in the 11 inch fan and it made a big difference.

The first hub I made for the 17 inch fan mounts them in the same orientation as in the jet engine. The next task is to make an adjustable blade hub.

An alternative to a multiple row arrangement is a two rotor contra-rotating fan with the advantage of taking the swirl out of the exhaust stream. If you use a same direction, multiple rotor fan you have to have stators in between the rotating rows and the swirl is still there requiring an exit stator row.

Nothing is simple!
That`s so true. If it were all easy, we would all be doing it!! Anyway, thanks for your time, effort and dedication. I, for one, am looking forward to your ultimate success. If the Russians can figure it out, so can you. ( No malice intended, Malish!)
Erik in Oz.
 
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