Doubly Excited Brushless Reluctance Machine (DEBRM) has gained much attention recently in the area of variable-speed constant-frequency generating systems and adjustable speed drives. Two types of reluctance rotor structure, axially laminated and simple salient rotors, are suggested in the DEBRM development. Due to the unconventional pole number combination of the stator and rotor, performance ...

Dynamics of a rotor supported by air bearings is strongly depends on the pressure distribution between the rotor and the bearing. In this study, internal pressure in air bearings is numerical and experimental analyzed for different radial clearances. Firstly the pressure distribution between rotor and bearing is modeled using Reynold's equation and this model is solved numerically. The rotor-be...

The rotor configuration of the brushless doubly fed induction generator (BDFIG) plays an important role in its performance. In order to make the magnetomotive force (MMF) space vector in one set rotor windings to couple both magnetic fields with different pole-pair and have low resistance and inductance, this paper presents a novel wound rotor type for BDFIG with low space harmonic contents. In...

The membrane domain of rotary ATPases (Fo/Vo/Ao) contains a membrane-embedded rotor ring which rotates against an adjacent cation channel-forming subunit during catalysis. The mechanism that allows stabilization of the highly mobile and yet tightly connected domains during operation while not impeding rotation is unknown. Remarkably, all known ATPase rotor rings are filled by lipids. In the cry...

Title of dissertation: DESIGN AND PERFORMANCE PREDICTION OF SWASHPLATELESS HELICOPTER ROTOR WITH TRAILING EDGE FLAPS AND TABS Jaye Falls, Doctor of Philosophy, 2010 Dissertation directed by: Professor Inderjit Chopra Department of Aerospace Engineering This work studies the design of trailing edge controls for swashplateless helicopter primary control, and examines the impact of those controls ...

Modeling of convection heat-transfer at the end-windings for thermal networks using lumped-parameters has been widely discussed in literature. Unfortunately, resulting coefficients are highly influenced by end-winding shape, area vicinity end-windings, cooling method this region (if any), as well size and power machine. This makes it extremely difficult designer to choose a suitable coefficient...

The two main sources contributing to scroll compressor vibration at running frequency are the residual rotational unbalance in the crank-rotor assembly and the reciprocating force due to the Oldham ring. The intent of this paper is to develop a rigid body model of the compressor vibrating on resilient grommets. This model is a design tool capable of identifying the sensitivity, of the steady-st...

The twin-screw compressor is constantly attaJ.ninq hiqher performance due to new rotor profiles, new rotor manufacturing technology and new designs. Besides this, new refrigerants as well as new lubricants can be expected on the market. Therefore there is always a need to update performance data. To m1nimize the number of test points and still receive representative data, there 1s a need of an ...

The objective of the research is to diminish unwanted forces generated by rotation and unbalanced rotor mass on the rotor of an electrical machine. These forces, dependent on rotational speed, cause vibration that, when occurring in the machine’s natural frequency, causes severe problems. Extra windings are built in the stator of the machine, and they are supplied with current to create an oppo...

According to tradition, permanent maglev cannot achieve stable equilibrium. The authors have developed, to the contrary, two stable permanent maglev impeller blood pumps. The first pump is an axially driven uni-ventricular assist pump, in which the rotor with impeller is radially supported by two passive magnetic bearings, but has one point contact with the stator axially at standstill. As the ...