F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
F01D1/00—Non-positive-displacement machines or engines, e.g. steam turbines
F01D1/24—Non-positive-displacement machines or engines, e.g. steam turbines characterised by counter-rotating rotors subjected to same working fluid stream without intermediate stator blades or the like