The design of super-cavitating propellers takes advantage of the development of air cavities on the blades’ surface to reduce drag and, ultimately, increase efficiency. The mechanism of flow modification induced by the development of a cavity on the propeller blades was investigated experimentally via phase-locked laser Doppler velocimetry measurements. A large cavity extending beyond the blades’ trailing edge and enclosing th...

A turbulent channel flow laden with elongated, fiber-like particles is investigated experimentally by optical techniques. The flow-particle inter-coupling is analyzed in the case of particles with an aspect ratio of 40 and 80, at two volume fractions, 10−5 and 10−4. An image processing technique is presented, which is employed to simultaneously obtain carrier flow velocimetry data and distribution and orientation data of dispe...

During maneuvers, propellers’ operation differs from their design due to strong modification of the wake field with respect to the straight-ahead motion. The consequent modification of the loads overstresses the mechanical components of the shaftline, exacerbates propeller side effects and worsens overall efficiency. Therefore, the analysis of these situations in the early design phase is pivotal to increase the operation capa...

This study analysed the anthropogenic microparticles in the stomach content of the European anchovy ( Engraulis encrasicolus ) in the Ligurian Sea (NW Mediterranean). The results showed that 30–40% of the anchovies had ingested anthropogenic microparticles (on average, 0.34 ± 0.29 fibres ind −1 and 0.12 ± 0.12 fragments ind −1 ). The fibres were probably ingested via filtration, and were significantly correlated with the gut f...