The Case For Ducted Fan VTOL

[@WarzSchoolchild]

Great presentation, thanks for sharing! ~ Miniturization is the next challenge, and the Christmas Stocking market is a kid's dream!

[@BattlesuitExcalibur]

I agree with SEThatered, you should experiment with ducted fans which incorporate a wirelessly actuated variable blade pitch rotor shrouded by the duct, in the place of a one piece, fixed pitch rotor. There will likely be a power requirement tradeoff, due to the increased mass of the variable pitch rotor assembly rotating (as compared to a solid plastic rotor). The advantage of course would be changes in height without increasing rotor RPM, thereby also conserving power and extending VTOL range.

[@SEThatered]

@AVIDLLC Did you experiment with variable pitch control (i mean only collective without cyclic) ? Coaxial rotors?

[@danielkeirsteadsr6939]

Could you build one into each wing ? it would correct a stalled wing and could make for a very short landing in the bush.

[@stanbilinski7538]

Hello, I am leading a design Team for Tesla Aircraft. I am adamant that we use ducted fans for our prototype, but wondering if contra ducted fan is best way to go for superior/clean thrust? Also, right down to the nacelle or duct. We are experimenting with a venturi shaped nacelle and a conventional shaped nacelle. I understand the benefits of a ducted fan vs. a open prop. What are your thoughts on a contra ducted fan?

[@TheBaconWizard]

lol

[@AVIDLLC]

We chose the single propeller to minimize both noise and complexity.

[@jehminjung89]

what's the noticeable benefits ?

[@alpha001ful]

Do you have a paper or workout where you did above studies, highest payload per unit of the vehicle column, ? Is there any way you can share that ? I am trying to build one . I might contact you later for consultancy.

[@stanbilinski7538]

p.s. Our concept is a hybrid and will have dual power plants. we are adopting the Honda Jet low-wing design, mounting the ducted fans on the wings, as close to the fuselage as possible for increased center line thrust in the event of an engine failure. We are still debating contra ducted fan and what would optimal amount of fan blades to if we go contra or not. Our concept is a 4-place GA type a/c. You may be of great help to our Team.

[@AVIDLLC]

Stan, There are always trade-offs to be made in every design. A properly designed counter rotating design can have reduced swirl in comparison to a single stage fan. However, that does come at the price of mechanical complexity and increased noise due to the blade-wake interaction. There are approaches to mitigate both. We would be happy to discuss in more depth and specifically for your application. Please contact us ([e-mail]).

[@timn4481]

whilst its true that less blades is better, and diameter is king, this presentation didnt address the elephant in the room. flow straighteners and tip clearance. and duct intake geometry. all critical to approach the theoretical 'root 2' difference. the 'root 2' is the best you will get and is, in practice, difficult to attain with many designs not achieving a net improvement due to the increased weight needed.

[@ufoengines]

Patent 6607162

[@pauljames1682]

Ring wings have too much drag not enough lift for the weight.