can be made with flexible materials one embodiment shown in fig4 uses flexible tube 400 with inner grooves 405 a flexible cylindrical shaft or rod 410 rotates within the outer tube this can be used for applications where local suction or blowing in complex inner cavities would be required another alternative shown in fig4 b forms the inner rotating part 400 from a flexible material so that it can be bent at the area 450 to attach the driving motor a rotary motor 450 or any other kind of motor can carry out the rotation of any of these embodiments one embodiment uses a magnetic levitation pump principle according to this embodiment the central shaft is made of a magnetic material an external coil will generates magnetic field and the external magnetic field causes the internal cylinder to rotate the rotating cylinder causes the fluid flow as described above one embodiment is for use in propulsion e g as a motor to drive a water vehicle such as a submarine this embodiment is shown in fig5 with two propulsion pumps 500 510 with rotating elements 502 512 that rotate in opposite directions 504 514 the cylinders have oppositely canted ridges 506 510 so that they both pump in the same direction this allows balance in the thrust generation a control element 520 enables setting the rotating speed.