This paper deals with open-shaft twin-screw refrigeration compressors in the 10 175 m3/h (10 100 CFM) range. Applications for such compressors are, for example,external combustion engine heat-pumps and transport refrigeration. The twin-screw compressor concept is discussed from following view-points; operational mode and rotor housing design drive arrangement bearings lubricants cooling volume ...

To better understand and predict the flight performance of X-configuration quadrotor aircraft using variable rotor pitch fixed speed to control aircraft, a tool including model, an aerodynamic interference new propulsive trim method is derived. The lifting rotors are modeled as circular wings, generate horseshoe vortices trailed from retreating advancing sides affect aerodynamics other rotors. ...

Increasing the efficiency of wind power conversion into electricity poses major challenges to researchers and developers turbines, who are striving for new solutions that can ensure better use local potential in terms both feasibility affordability. The paper proposes a novel concept systems with counter-rotating rotors integrate either conventional or electric generators, by means same differe...

A prototype of a neutral Re-based metallacyclic rotor, assembled in a one-step process, possesses a para-phenylene rotor that rotates in solution with respect to the stator.