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In this paper, the numerical analysis on an air-core pulsed alternator is presented. Since compulsators are characterized by very fast electromechanical transients, their accurate analysis requires strong coupling between the equations governing the electrical and the mechanical behaviors. The device is investigated by using a dedicated numerical code capable to take into account eddy currents, compensating windings, as well as the excitation/control circuits. Furthermore, the code is capable of modeling centrifugal forces and vibrations acting on the shaft due to electric and mechanical unbalances or to misalignments of the shaft from its centered position. This makes the code a very powerful tool during the design phase. Examples of application of the code to machines with nonuniform compensating shield and with shorted compensating windings are shown. [ABSTRACT FROM PUBLISHER]

In this paper, the synthesis and design of a new device for the energization and characterization of magneto-rheological fluids (MRF) for haptic interfaces are presented. Due to the core structure and feeding conditions, only a three-dimensional numerical analysis provides an accurate prediction of the electromagnetic quantities and the theological behavior of an excited specimen. The design constraints are shown in details and the results in terms of magnetic field inside the fluid and its spatial resolution are discussed. [ABSTRACT FROM AUTHOR]

In this paper, the numerical analysis of a complete launch package, composed by a homopolar generator feeding a rail launcher, is described. Because of the nonlinear and time varying characteristics of both generators and launchers, a separate analysis of the two devices is not always able to provide highly accurate previsions about the performance of the overall system. The analysis has been performed here by using an integral formulation that transforms the Maxwell's equations into an equivalent electric network, whose parameters vary together with the evolution of the system. The presence of sliding contacts and the consequent velocity skin effect in both the generator and the launcher have been taken into account. The most important electromechanical quantities have been reported; the results of the simulations shows the effectiveness of the software used for this coupled analysis. [ABSTRACT FROM AUTHOR]

Analyzes the performance of the multistage railgun in order to characterize the values of the quantities influencing the performances of the railgun in terms of velocity of the pellet. Measurement of the railgun; Values of the main characteristics of the multistage railgun; Comparison between the velocity at the end of a single stage railgun and the final velocity at the end of a double stage railgun.

Presents information on a study which used a wavelet transform method to solve multiconductor transmission line equations. Acquisition of a Fourier-type approach for transient analysis of transmission lines; Numerical characteristics and performance of the method; Results; Conclusions.

Presents information on a study which described dual formulations of a hybrid finite element method/Method of Moments (FEM/MOM) method for nonlinear analysis. Mathematical formulation; Results of the study; Conclusions.

Focuses on a study which investigated the transition between the sections of a generator driven induction launcher. Background of the model; Results of the experiment; Implication of the results.

Provides information on a procedure for the design of induction coilguns in order to obtain thermal and mechanical stress that do not exceed the allowed values in the sleeve. Mathematical model of the design; How the mechanical stress are measured; Conclusions.