In this description of the Enigma rotor movement sequence the following conventions have been adopted. The three rotors are numbered from right to left as seen from the machine operator’s viewpoint thus, the ‘fast’ or right hand rotor is Rotor 1, Rotor 2 is in the middle position and the ‘slow’ or left hand rotor is Rotor 3. The associated ratchets, stepping levers and notches are similarly des...

Abstract This article presents the Proportional Integral Resonant Controller (PIRC-controller) as a novel control strategy to suppress lateral vibrations and eliminate nonlinear bifurcation characteristics of vertically supported rotor system. The proposed algorithm is incorporated into system via an eight-pole electromagnetic actuator. designed such that law employed generate eight different c...

Effects of magnetic saturation on various equivalent circuit models of an induction motor are studied. The parameters of 2.2-kW and 37-kW motors with closed rotor slots are analyzed using finite element computations. Both skewed and unskewed rotor slots are studied. The magnetizing inductance not only depends on the main flux, but is also dependent on the rotor current, especially if the rotor ...

A new online identification methodology for estimation of the rotor flux components and the main electrical parameters of vector controlled induction motors is presented in this paper. The induction motor model is referred to the rotor reference frame for estimation of rotor flux and rotor parameters, and referred to the stator reference frame to estimate stator parameters. The stator parameter...

Tip leakage loss introduces major part of losses of the rotor in axial gas turbines. Therefore, the rotor blade tip has a considerable effect on rotor efficiency. To understand the flow physics of the rotor tip leakage, we solve the flow field for different tip platforms (passive flow control) and by considering coolant tip injection (active flow control). Various blade tip configurations s...

This paper presents the development of a multibody dynamics model of a VTOL teetering rotor. The developed model includes a teetering hub, containing a flexure and torque tube, rotor blades, pitch links, and swashplate system. A non-teetering rotor configuration, which modified the baseline teetering rotor by removing the teetering hinge, is also developed, and its aeromechanics characteristics...

In this paper, we characterize the rotational dynamics and observe rotor-rotor interactions within a crystalline, three-dimensional array of dipolar molecular rotors. The rotating portion of each rotor molecule consists of a dipolar fluorine-substituted phenyl group. The phenyl rotors are connected by acetylene linkages to bulky triphenyl methyl groups which are held rigid in the crystal lattic...

In this paper, two kinds of vibrations are considered for a composite Timoshenko rotor: longitudinal-torsional vibration and two plane transverse one. The kinetic and potential energies and virtual work due to the gyroscopic effects are calculated and the set of six governing equations and boundary conditions are derived using Hamilton principle. Differential quadrature method (DQM) is used as ...

The performance of Vector Controlled Induction Motor drive depends on the accuracy of rotor resistance which will vary with temperature and frequency. The MRAS approach using reactive power and flux as a state variable for rotor resistance estimation makes MRAS computationally simpler and easy to design. In this paper, Rotor Flux based MRAS (RF-MRAS) and Reactive Power based MRAS (RP-MRAS) for ...