KJ66 turbojet engine

Before we custom-designed our much more powerful M400 turbine, we made this smaller existing KJ66 model in order to get familiar with the materials and type of challenges we would face in the big project that followed!
  • CAD 3D design

    Since this is an existing turbojet design, a full set of plans and instructions was acquired to produce this engine. A complete 3D CAD model was first drawn after which production could begin.

  • Initial parts production

    Apart from the compressor wheel and turbine disk, all parts were CNC machined, turned, casted, rolled, 3D printed etc.

  • Stator production

    The stator assembly was fully self-made from stainless steel (though Inconel would have been even better, but much harder to source)

  • Combustion chamber production

    The combustion chamber liner was hand-made, since we did not yet have a CO2 laser at that time. The big perforations were pressed inwards to allow for a more laminar inflow of the cooling air in the combustion chamber.

  • Complete KJ66 turbine

    The completed turbojet engine mounted on the thrust-measuring carriage on top of the control box.

  • Custom data acquisition/logging unit

    A fully-custom control- and data acquisition unit was developed and programmed in order to drive the different systems, and log the array of sensors gathering data.

  • Completed control box

    The finished test-setup could easily be carried by hand to the testing location.

  • Stainless exhaust cone

    An exhaust cone was produced.
    While the turbine would happily spin up to a maximum of 120 000rpm without it, the exhaust cone channels the exhaust gasses much more efficiently, more than doubling the thrust that the engine is generating.

  • Testrun logged data processing

    Many testruns were done and the gathered data was subsequently processed to learn more about how efficient the combustion was, and to find the relations between thrust, chamber pressure, exhaust temp, rpm etc.