Post by turbotom on Mar 8, 2014 18:03:28 GMT -5
Hi altogether -
since this thread refers to my website and I may be one of the individuals with some detailed "non-professional" knowledge on the TS-20b / TS-21 starter engines, I dare to contribute ;-)
I've still got one of the TS-21 engines (by the way in pristine condition...) and I had been thinking a lot about putting it to use in a "serious" application. For a few reasons I decided not to do so which were:
- the rather low pressure ratio, the moderate turbine inlet temperature and the free power turbine design without a dedicated NGV result in a ridiculously high SFC.
- in order to achieve a half-way acceptable throttle range (which is mandatory for most "serious" applications), the fuel nozzles will have to be modified to operate as the "spill" type, i.e. a return line will have to be introduced at the rear of the swirl chamber and somehow routed outside.
- since the gas generator rotor can hadly be accessed from the outside, measuring N1 will be somewhat awkward. Initially, when I still considered the TS-21 a viable starting point to make an ultralight turboprop, I considered replacing the stock starter with a specifically designed brushless starter/generator that doubles as a tach generator. Since I never continued with the project, I ended up with some preliminary drawings...
For a "just for fun" project without any requirements for longevity or fuel efficiency (say go kart), the TS-21 may be a good choice but still, the aforementioned modifications would make life easier. I had been promised some surplus fuel nozzles so I could experiment with the spill modification without risking a "good" nozzle but as yet, nothing dropped in.
Marc-
I frequently pass Karlsruhe when visiting a friend of mine close to Achern or on my way to some of my customers in Switzerland. Maybe we could arrange a meeting eventually?
Cheers,
Thomas
P.S. for a nice set of photos of a sectioned TS-20b, please feel free to download this archive: www.turbinemuseum.de/files/TS-20b_cut.zip
since this thread refers to my website and I may be one of the individuals with some detailed "non-professional" knowledge on the TS-20b / TS-21 starter engines, I dare to contribute ;-)
I've still got one of the TS-21 engines (by the way in pristine condition...) and I had been thinking a lot about putting it to use in a "serious" application. For a few reasons I decided not to do so which were:
- the rather low pressure ratio, the moderate turbine inlet temperature and the free power turbine design without a dedicated NGV result in a ridiculously high SFC.
- in order to achieve a half-way acceptable throttle range (which is mandatory for most "serious" applications), the fuel nozzles will have to be modified to operate as the "spill" type, i.e. a return line will have to be introduced at the rear of the swirl chamber and somehow routed outside.
- since the gas generator rotor can hadly be accessed from the outside, measuring N1 will be somewhat awkward. Initially, when I still considered the TS-21 a viable starting point to make an ultralight turboprop, I considered replacing the stock starter with a specifically designed brushless starter/generator that doubles as a tach generator. Since I never continued with the project, I ended up with some preliminary drawings...
For a "just for fun" project without any requirements for longevity or fuel efficiency (say go kart), the TS-21 may be a good choice but still, the aforementioned modifications would make life easier. I had been promised some surplus fuel nozzles so I could experiment with the spill modification without risking a "good" nozzle but as yet, nothing dropped in.
Marc-
I frequently pass Karlsruhe when visiting a friend of mine close to Achern or on my way to some of my customers in Switzerland. Maybe we could arrange a meeting eventually?
Cheers,
Thomas
P.S. for a nice set of photos of a sectioned TS-20b, please feel free to download this archive: www.turbinemuseum.de/files/TS-20b_cut.zip