Abstract: An additional turbine, an air-to-water heat exchanger, and an air-to-air heat exchanger are added upstream of a recuperated gas turbine engine. Incoming air at atmospheric temperature is expanded and cooled in the additional turbine and then passes through the air-to-water heat exchanger where it is used to cool warm water to a suitable drinking temperature. The cool air then passes through the air-to-air heat exchanger, where it precools the incoming atmospheric temperature air. The output shaft of the additional turbine is coupled to an additional compressor downstream of the original compressor of the engine, thus resulting in a higher net pressure ratio.

Abstract: A turbine engine is provided with a primary surface, counterflow heat exchanger for preheating the compressed air from the compressor prior to its entry into the combustor. The recuperator includes three concentric cylindrical shells which completely encircle the hottest components of the engine. The outermost shell includes a plurality of inlet openings for receiving air from the compressor, and a plurality of outlet openings for discharging the air into the combustor. The innermost shell includes a plurality of inlet openings for receiving gases from the turbine and a plurality of outlet openings communicating with an exhaust duct. The central shell is a corrugated tube which divides the space between the inner and outer shells into a plurality of concentric annular flow chambers, and allows heat transfer between adjacent chambers Annular turbulators may be inserted in the chambers.

Abstract: A turbine engine is provided with a primary surface, counterflow heat exchanger for preheating the compressed air from the compressor prior to its entry into the combustor. The recuperator includes three concentric cylindrical shells which completely encircle the hottest components of the engine. The outermost shell includes a plurality of inlet openings for receiving air from the compressor, and a plurality of outlet openings for discharging the air into the combustor. The innermost shell includes a plurality of inlet openings for receiving gases from the turbine and a plurality of outlet openings communicating with an exhaust duct. The central shell is a corrugated tube which divides the space between the inner and outer shells into a plurality of concentric annular flow chambers, and allows heat transfer between adjacent chambers. Annular turbulators may be inserted in the chambers.