Abstract: A coaxial pump or turbine module includes an integral, modular motor or generator comprising a magnet structure containing radial or axial permanent magnets and/or induction coils detachably fixed to a rotor, and a stator housing detachably fixed to the module housing. Working fluid is directed axially through a flow path symmetrically distributed within an annulus formed between the module housing and the stator housing. The stator housing can be cooled by the working fluid, or by a cooling fluid flowing between passages of the flow path. The flow path can extend over substantially a full length and rear surface of the stator housing. A plurality of the modules can be combined into a multi-stage apparatus, with rotor speeds independently controlled by corresponding variable frequency drives. Embodiments include guide vanes and/or diffusers. The rotor can be fixed to a rotating shaft, or rotate about a fixed shaft.

Abstract: A coaxial pump or turbine module includes an integral, modular motor or generator comprising a magnet structure containing radial or axial permanent magnets and/or induction coils detachably fixed to a rotor, and a stator housing detachably fixed to the module housing. Working fluid is directed axially through a flow path symmetrically distributed within an annulus formed between the module housing and the stator housing. The stator housing can be cooled by the working fluid, or by a cooling fluid flowing between passages of the flow path. The flow path can extend over substantially a full length and rear surface of the stator housing. A plurality of the modules can be combined into a multi-stage apparatus, with rotor speeds independently controlled by corresponding variable frequency drives. Embodiments include guide vanes and/or diffusers. The rotor can be fixed to a rotating shaft, or rotate about a fixed shaft.

Abstract: A coaxial pump or turbine module directs working fluid past a rotor and through a flow path symmetrically distributed within an annulus formed between an outer module housing and an inner motor or generator coil housing. The inner housing can be cooled by working fluid in the flow path, or by a cooling fluid flowing between passages of the flow path. The flow path can extend over substantially a full length and rear surface of the inner housing. The rotor can be fixed to a rotating shaft, or rotate about a fixed shaft, which can be threaded into the motor and/or module housing. A plurality of the modules can be combined into a multi-stage apparatus, with rotor speeds independently controlled by corresponding variable frequency drives. The motor or generator can include radial or axial permanent magnets and/or induction coils. Embodiments include guide vanes and/or diffusers.