Rotary apparatus for heating fluids and for recycling heated fluids, related method and uses

A method for recycling fluids in the rotary apparatus, the method comprising:

• (a) obtaining a rotary apparatus for inputting thermal energy into fluids, comprising:
• a rotor comprising at least one row of rotor blades arranged over a circumference of a rotor hub mounted on a rotor shaft and forming at least one rotor blade cascade, respectively, and
• a plurality of stationary vanes arranged into at least one stationary vane cascade adjacent to said at least one rotor blade cascade,
• the rotor and the plurality of stationary vanes being enclosed in a duct formed in a casing between at least one inlet and at least one outlet,
• (b) supplying optionally preheated fluid into the rotary apparatus through at least one inlet, and operating the rotary apparatus such that thermal energy is imparted to fluid propagating inside the casing between at least one inlet and at least one outlet by virtue of series of energy transformations occurring when said fluid successively passes through rotating blades and stationary vanes, whereby a stream of heated fluid is generated, and
• (c) recycling a part of heated fluid by returning said heated fluid, via the fluid circulation arrangement, into a region of the duct between at least one inlet and at least one rotor blade cascade, when said fluid propagates in the duct between at least one inlet and at least one outlet.