device fitted with a rotor, the size of which is small in comparison with the size of the conduit and the rotational frequency of which is a function of the local velocity of the fluid in which it is submerged, rootormõõtevahend, mille mõõtmed on toru läbimõõduga võrreldes väikesed ja mille pöörlemissagedus sõltub vedeliku, millesse see on sukeldatud, kohalikust kiirusest
