Podstrona: GT60A1 - micro gas turbine engine / Wizytówka pracownika PRz

Ca. 2009 , I started my gas turbine project. A this time micro scale turbines becomes popular. As a former "large scale" gas turbine engineer I feel "quite comfortable" i this subject.  From this perspective it was full scale illusion. All my effort to build working turbine took 11 years. 4 years to make PhD,  additional 7  "hobby years" and next two prototype engines to learn how to do it " proper way".  AFIK it is the smallest turbojet design and build in Poland.

There is a sketch called "Gonzo The Great Motocycle Act" -  https://www.youtube.com/watch?v=4tRPEd_LGIQ
which is essence of engineering.

"If at first you don't succeed, fail, fail again!"

Micro turbines pioneer eng. Kurt Schreckling build three prototypes FD-1,FD-2, FD3/64 considering his practice third engine work "as expected". He also design KJ-66 which is common layout for majority of model turbines.  

From my experience :

Engine no.1 mSO-1  - External diameter 102 mm  - engine "forced to work" by assembly thermocouple in cold spot. 
                                      Overtemperature with badly designed "bearing preloading system", that leads to damage
                                      compressor impeller. Generally overconstrained design.

                                      Design 1 - initial design ( rotor/internal, compressor, combustor, turbine, jetpipe )
                                      Design 2 - redesign ( compressor, combustor )

Engine no.2 GT60  -   External diameter 98,5 mm. Works well at idle conditions. Overheats at operating speed.

                                      Design 3 - redesign ( rotor/internal, compressor , combustor , jetpipe )

Engine no.3 GT60A1 - External diameter 96.5 mm.Redesign GT60. Works as expected, which was quite surprise.

                                      Design 4 - redesign ( rotor/internal , compressor , combustor , turbine, jetpipe )
                                      Design 5 - redesign ( jetpipe in progress )

                                      https://www.youtube.com/watch?v=r7HeeL3825I

After first prototype      - I know that without experience "scientific effort" are more or less "wishfull thinking",

         second prototype - I know that design decision was better but needs to be redesigned once again,

         third prototype      - I know that's design is good and needs tweaking to be reliable as commercial products.

Summarizing - four compressor designs, four  combustor designs, three rotor/internal and two turbine designs, 1+ jetpipe designs, excluding parts that needs to be remanufactured due different reasons.

The best of this project to me is to feel comfortable with "engineering experience".

“(1) He must be competent,
 (2) He must exercise good judgment,
 (3) He must have character.

 By itself, competence is meaningless without character and good judgment.” ― Harold G. Moore