Retour au reportage Retour au reportage

© Ahmed ELDEMERDASH / Thomas LEWEKE / Stéphane LE DIZES / IRPHE / CNRS Images



Dancing rotor

Rotors are used in many applications to exchange energy between a mechanical system (vehicle, turbine) and the surrounding fluid (such as air or water). This image shows the extreme deformations of a small rotor fitted with two flexible polyethylene blades when operating in water. Depending on the frequency of rotation, the speed of the incident flow and the inclination of the blades, largeamplitude deformations may appear in either direction, affecting its performance. In a liquid, this phenomenon can be very pronounced since the forces are proportional to the density of the fluid. Studying these surprising behaviours could lead to possible improvements for tidal turbines and underwater drones. This image is one of the winners of the 2022 La preuve par l’image (LPPI) photography competition.

CNRS Institute(s)

Regional office(s)

Scientific topics

CNRS Images,

Our work is guided by the way scientists question the world around them and we translate their research into images to help people to understand the world better and to awaken their curiosity and wonderment.