an arrangement for dissipating heat from components producing high heat flux densities , such as computers , features a combination fan and fluid pump with a magnetic coupling which acts across a fluid - tight partitioning can . the pump has a pump wheel connected to a first permanent magnet , and an electronically commutated internal - rotor motor to drive it . the motor has a stator inside which is rotatably arranged a rotor equipped with a second permanent magnet . interaction between the first and second permanent magnets creates the magnetic coupling . the stator of the internal - rotor motor is arranged radially outside the magnetic coupling . a first shaft , arranged on the outer side of the can , serves for rotatable journaling of the rotor of the internal - rotor motor and a second shaft inside the can serves for journaling the pump rotor .