Propless ducted fan ?

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Riggerrob

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We already know that ejectors work well at small Reynolds numbers.
How thick is the boundary layer affected by ejectors?
 

Aesquire

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By "compressed air" they don't mean a pressure tank. It's the same as a compressor on a turbo jet. Spinning blades.

Analog has been an American Science Fiction/Science Fact magazine since the late 1940s? I have issues from 1953, when it was titled Astounding. Some of the best SF ever, Dune, Dragonsinger, etc. And the Fact articles run towards the cutting edge. They were talking this stuff in the 1960s.

You want REAL Propless? Electric plasma magnetically accelerated instead of a ducted fan... Over to You, Henryk! :)
 

henryk

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"Very high efficiency concept that utilizes a boundary layer ingestion propulsor on the fuselage, as well as wingtip propellers. A single speed combustion engine drives the rear fuselage fan at very high efficiency, due to the Goldschmied fuselage propulsor. The wingtip propellers are driven by batteries to provide extra thrust for takeoff and climb, and act as wingtip vortex turbines at cruise to extract energy to recharge the batteries. The combination provides a variable disc loading propulsion system that can attempt to achieve optimal cruise efficiency (~200 passenger mpg, or 50 mpg with 4 people at speeds of 125 mph). "
 

EzyBuildWing

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Analog was/is a great Magazine...it carried some interesting accounts by Harry Stine about the "Dean Drive".....a reactionless-drive for mechanical propulsion in outer-space, which Harry said he saw work.
Anaolg also carried a brilliant SciFi stories by Keith Laumer (who also wrote books on Model Aircraft design).
Best story by Laumer is called "Dinosaur Beach" , and free-read is available here, I think:
baencd.freedoors.org/Books/Odyssey/0743435273__18.htm
 

Aesquire

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One pretty good story from Analog had ramjets that used electrical power to make hot plasma out of air, injecting it into the ramjet, instead of burning fuel as the in-atmosphere engines of an orbital space plane.

A delta wing of football field size, to carry the nuclear reactor to get the needed power. Some things, like Ekranoplans, benefit from the right scale of size, so as a home built airplane, I don't see how you can get the energy density storage/production into something that fits a T hanger.

If you want to burn several hours looking at engines you really don't want to fire up in your driveway... Engine List 1 - Atomic Rockets



My initial reaction to the OP "Dyson Fan"( entrainment fan ) craft is that ducting losses are likely to make it impractical. That was the failure on the XFV-12. And the Avro Aerocar... And...
 

Aesquire

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Specifically, the rectangular ducts have stagnation issues at the corners, and I wonder what pressure you need to pump into the "ring" to get enough velocity through the slits to accelerate the mass of air to useful thrust.

Since the pressure is going to drive the thickness/weight of the ducts a lot. My guess is more than the structural issues of drag forces and thrust forces on the external parts of the duct/pylon.

and did anyone else notice that big retractable ducts seem to use up a Lot of volume in the fuselage?
 

Bill-Higdon

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Salem, Oregon, USA
By "compressed air" they don't mean a pressure tank. It's the same as a compressor on a turbo jet. Spinning blades.

Analog has been an American Science Fiction/Science Fact magazine since the late 1940s? I have issues from 1953, when it was titled Astounding. Some of the best SF ever, Dune, Dragonsinger, etc. And the Fact articles run towards the cutting edge. They were talking this stuff in the 1960s.

You want REAL Propless? Electric plasma magnetically accelerated instead of a ducted fan... Over to You, Henryk! :)
One of Stine's paid research gig's involved using Coanda nozzle ram jets for submarine propulsion :eek:
 
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