Ducted fan aircraft

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Malish

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Oct 11, 2013
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812
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Russia. City of Volgograd
Lovely! Any news, new developments? How are you all doing?

Thanks.
Aircraft is not flying now, as it's partially disassembled for some modifications as we're getting it ready for production phase. A lot of work need to be done before this aircraft can be produced in numbers as a kit, that could be ready for sales. Because of recent situation we're thinking to move production out of Russia, preferably to US. But this will require additional finances which we don't have for now, so we're doing what we can do and hopping for best.
 

Malish

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Joined
Oct 11, 2013
Messages
812
Location
Russia. City of Volgograd

misterstax

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Jan 25, 2022
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Malish said:
Because of recent situation we're thinking to move production out of Russia, preferably to US.

That would be great! I would think there would be a lot of support in the US for that. I wish there was something I could do to help.

As for the exhaust nozzles; I was wondering about that. Would it increase any stress or pressure on the Fan blades or assembly? If I remember correctly, reduction in diameter in flow situations equates to an increase in exit velocity, but I think the activating mechanism encounters some increase in dynamic head on the discharge side. I can't figure out what the loading on the fans or motor would be, but if they can take the additional pressure, I think variable geometry nozzles could be very useful and extremely cool! And because a ducted fan doesn't have hot exhaust, the vanes could be made of a much lighter and more affordable material.
 

Malish

Well-Known Member
Joined
Oct 11, 2013
Messages
812
Location
Russia. City of Volgograd
As for the exhaust nozzles; I was wondering about that. Would it increase any stress or pressure on the Fan blades or assembly? If I remember correctly, reduction in diameter in flow situations equates to an increase in exit velocity, but I think the activating mechanism encounters some increase in dynamic head on the discharge side. I can't figure out what the loading on the fans or motor would be, but if they can take the additional pressure, I think variable geometry nozzles could be very useful and extremely cool! And because a ducted fan doesn't have hot exhaust, the vanes could be made of a much lighter and more affordable material.

Exhaust nozzles(afterburners) in our aircraft could be only a "fake" one because in ducted fan design exhaust area can't be reduced more then 10% of the fan area and we already have that done in our aircraft. Reducing anymore exhaust area would "chock" the fan. So, this nozzles would be only for "look" and have NO moving parts.
 

misterstax

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Joined
Jan 25, 2022
Messages
16
"in ducted fan design exhaust area can't be reduced more then 10% of the fan area".

Ah! I understand. Very interesting...it seems to me Ducted Fans are kind of in a world of their own. So much to learn, so little time. One lifetime's not enough!
 

Urquiola

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Joined
Aug 23, 2013
Messages
297
Location
Madrid, Spain
What about an Stipa type of Hollow Fuselage, propeller inside, with only the lower half of duct shaped as an airfoil?
In theory, this could reduce drag from duct, and provide some extra lift, in the line of Custer Channel Wing concept.
Lorin Ramjet
As far as I know, the possibility of a counterpropeller was never explored in CCW. Blessings +
 

Attachments

  • Counterpropeller for Air Propeller Driven Craft -R Wagner US1609978A.pdf
    274.9 KB · Views: 2
  • Ultralight and very light ducted fan propulsion system complex design optimization -Daniel hau...PDF
    1.9 MB · Views: 0
  • Design of a Rocket Engine Thrust Augmentation Ejection Nozzle -Jafarzadeh Sepideh ASU -NASA.pdf
    19.7 MB · Views: 0
  • Nozzle shapes  -Bosch manual  auto tech.jpg
    Nozzle shapes -Bosch manual auto tech.jpg
    45.6 KB · Views: 0
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Malish

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Joined
Oct 11, 2013
Messages
812
Location
Russia. City of Volgograd
Some people said that our aircraft under powered.
Here new video show our aircraft climbing capabilities at MTOW(two pilots on board and full fuel) 1400kg. Fan's static thrust at takeoff power - 350kg.

 

Malish

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Oct 11, 2013
Messages
812
Location
Russia. City of Volgograd
That is four to one weight to thrust. Modern aircraft are more around three to one or two to one. Or military is more than one to one.

We're working on fan's efficiency(new blades design) and hopefully we will get 15% thrust increase. Also production aircraft will have less airframe weight(about 200kg less). All of this will make aircraft thrust to weight ratio 0,3(or three to one) and I think it's will be good for sport aircraft.
 

BBerson

Light Plane Philosopher
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Dec 16, 2007
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Port Townsend WA
We're working on fan's efficiency(new blades design) and hopefully we will get 15% thrust increase. Also production aircraft will have less airframe weight(about 200kg less). All of this will make aircraft thrust to weight ratio 0,3(or three to one) and I think it's will be good for sport aircraft.
Less weight is always helpful. A more favorable thrust loading (larger duct) is guaranteed to improve static thrust.
 

Malish

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Joined
Oct 11, 2013
Messages
812
Location
Russia. City of Volgograd
Less weight is always helpful. A more favorable thrust loading (larger duct) is guaranteed to improve static thrust.

Yes, my first design had single 960mm ducted fan and on the stand it's developed 450kg static thrust and aircraft would have 1000kg MTOW.

design (Large).jpg
DCP_4716 (Large).jpg
 
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