Low Bypass Turbofan Jet Engine

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Revision 1 (file Rev_1.zip) see second picture

added combustion liner (Single Annular Can), fuel nozzles and turbine stand (in three pieces)

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This is a first step study around a working 50 Kg thrust engine, a simplified model aimed to study the assembly sequences, volumes and components' layout in general. Once completed it will sit on my desk as a display model and the second design phase will include the theoretical studies outputs.

In order to decrease the complexity of the model you'll notice some conceptual mistakes (such as the bearings directly mounted on hot components like the HP and LP nozzles, compressor disks shapes and approximate aerodynamic profiles) but besides that, the model is created reflecting the actual design of the full size/working engines.

The combustion chamber and fuel injectors are missing, they will be included in the rev. 1.

If you'd like to build this thing you need the following items. I got them from e-bay and/or hobbyking.com

Bearings:

LP rotor: #2 688zz

HP rotor #1 6705zz, #1 6810zz

Hardware:

LP shaft: threaded rod M8 L=220

6 Metal push rod M3x300 (from hobbyking)

M2x6

M2x8

M2x10

M2.5x10

epoxy glue

LP Fan:

12 Blade High-Performance 120mm EDF Ducted Fan Unit (from hobbyking)

Tools:

sand paper

files

drill bits (1.5 , 2 , 2.5 and 3mm) or reamers

hobby woodcraft lathe (optional)

I printed all the big items at medium resolution (0.25), 10% infill and wall thickness set to 2 shells. Complex and small items like statoric vanes an compressor disks were printed at high res. (0.15)

For the compressor rotor assembly you need to cut the M3 Push Rods to the right length and weld (I used an electric welding solder) an M3 nut at the not threaded end.

For the external shell I used the ducted fan shroud (see picture). The gap between the modified fan shroud and the right turbine length has been filled with the printed component "€œExternal can.stl".€

Printed parts have been painted with glossy black as base coat and finished with lacquer metalizer.

All the printed parts require sanding, filing and reaming in order to correctly mate and allow the rotors to spin with no interference. A small lathe would help.

Pictures of the completed model, along with assembly instructions will follow.