Hi, there are real improvements possible in aircraft propulsion if we use the following strategy;
1.0 Distribute the power to many smaller fans around the airframe
2.0 Ingest the aircraft boundary layers into the fans
3.0 Inbed the fans and motors into the airframe to avoid nacelle drag
4.0 Develop trailing edge control jets to provide thrust and control
But we will need a string of new technologies:
a. Light weight Electrical transmission
b. Multi MW high speed generator
c. High power stable mixflow fan
d. Wing/fan air intake aerodynamics
e. High speed light MW range motors for fans
Who wants to do a collaborative project?
NASA is currently working on the similar concept Distributed Electric propulsion But not exactly same.
I was also looking to do my B. Tech. Project on similar topic in electric propulsion.
So I will be very greatfull to you, If I can get this opportunity.
I am only interested in electric propulsion for space drives.
Some clarifications are required regarding electric propulsion being discussed:
1) What would be the typical size/ scale of the aircraft
2) If the trailing edge control jets are cold how economical it would be compared to hot ones.
3) Current electrical storage systems i.e batteries are having weight issues for large capacity that limits thrust to weight ratio for long range missions.In this regard how is the scope of super-capacitors.
4) The idea to "Inbed the fans into the air-frame to avoid nacelle drag" would introduce interference effect due the air-frame. There would be some trade off between the nacelle drag and interference effect on the fan performance. This requires special attention for efficient design.
The task appears promising and i would be interested in wing/fan intake aerodynamics and development of control jets
Hi Mr Varpe, I will address your questions:
1) The size is without limit the ideas are applicable to all sizes. However, it is in the largest planes that one can afford to introduce great complexity to get performance improvement.
2)THe trailing edge jets are providing almost all the thrust so the massflow is high. Close to Mach 1 though subsonic, a high massflow because the effective bypass ratio is to be very high maybe 20:1. The power is generated by a large gas turbine mounted in the fuselage. The only heat added to these jets would be the waste heat from cooling the electric motors.
3) battery storage is not a central theme in this idea the power source is expected to be kerosene but the SFC would be much higher than existing machines. However, batteries could be added to the system as could photo voltaics.
4) Yes the deformation of the wings to allow the introduction of the fans will be significant. There will be major challenges to tailor the wing:air intake to allow stable ingestion of the boundary layer without significant deterioration to the wing performance (get it right, one might even extend the range in terms of stall margin). The size of fans I anticipate is in the range of 1m diameter maybe 2MW power. One would mount such a fan approximately every 2 to 3m of span. The axis of rotation would be maybe at 45 deg to the vertical. These fans are actually small enough that they almost fit inside an unaltered wing profile (for a large aircraft). The motor would be underneath the fan and may need a blister on the lower or pressure side of the wing. Here, I hope the drag consequences are not too great. I will add a picture later. If it is possible the nacelle will be part of the wing and it will not be possible to identify its drag: just a wing with a propulsor in it!
Keep thinking about it!
cheers Martin
Who wants to collaborate in developing new algorithms for optimizing low-thrust interplanetary trajectories? I'm trying a novel approach and need someone to tell me if my idea is worth trying some program development as a test of its validity.
Maybe a gain could be made by designing some of the structural parts to carry field flux.
- Badges
- Science topic