Performance Development History-10 kw Turboalternator

The performance development history of a small gas turbine for the U. S. Army 10 kW turboalternator is discussed. The design incorporates a single-stage centrifugal compressor and single-stage radial inflow turbine, mounted back-to-back on a common shaft rotating at 93,500 rpm and directly coupled to a variable frequency solid alternator. Total accumulated running time, at rated speed during development, exceeded 20,000 h; in addition, a 2000 start/stop test was successfully completed. Gas turbine performance was found to be quite sensitive to compressor and turbine clearances as a consequence of the small compressor and turbine blade heights. With accurate control of these clearances, it was possible to attain average engine specific fuel consumptions meeting contract requirements of 1.1 lb/hp·h with a low rated turbine inlet temperature of 1330°F.