The aerodynamic performance of a reduced-scale coaxial rigid rotor system in hover and steady forward flights was experimentally investigated to gain insights into the effect interference between upper lower rotors influences advance ratio, shaft tilt angle lift offset. featured by 2 m-diameter, four-bladed hingeless installed test rig. Experiments were conducted ?3.2 m wind tunnel at China Aer...

Active magnetic bearings, which are open-loop and unstable, require a feedback control system to ensure stable operation of the rotating machines that they support. Proportional-integral-derivative (PID) controllers widely used in field applications these bearings for this purpose. PID designed work effectively within linear region machines. Due inherent nonlinearity active large unbalance forc...

Abstract This paper presents the results of a theoretical and experimental investigation potential enhanced groove geometries to increase bearing clearance Herringbone Grooved Journal Bearing (HGJB) supported rotor. The study investigates various different complexities their effect on stability threshold particular rotor geometry. obtained from rigid-body rotordynamic model suggest an more than...

In this study, a moderately flexible rotor is investigated experimentally in water channel. The consists of single blade with simplified rectangular geometry and tested various pitch angles at different rotational speeds. flapwise bending deformation induced torsion the are measured using image processing tools, flow fields extracted Particle Image Velocimetry. behaviour depends strongly on ang...

According to International Maritime Organization, emissions coming from global shipping are expected increase 50% 250% by the year 2050. This concern led introduction of various regulations that aims encourage ship owners and builders explore innovative renewable technologies. The main focus this article is on wind-assisted propulsion technologies, as a complement propulsion, such rigid sail, s...