We discuss evolution of the magnetic flux density and angular velocity in a molecular cloud core, on the basis of three-dimensional numerical simulations, in which a rotating magnetized cloud fragments and collapses to form a very dense optically thick core of > 5 × 10 cm. As the density increases towards the formation of the optically thick core, the magnetic flux density and angular velocity ...

Distribution of magnetic flux density in electromagnetic (EM) flow meter is significantly important for obtaining accurate flow rate. Helmholtz coils are used to generate homogenous magnetic flux density in the cross section of flow pipe of electromagnetic (EM) flow meter is presented in this paper. In this work, a simulation model with the EM module of finite element analysis software, COMSOL ...

In this study, a set of self-consistent coupled-integral equations for the local magnetic flux and current distributions in a finite superconducting hollow cylinder under an axial magnetic field has been directly derived by using the Biot-Savart law within the framework of the critical-state model. The equations were first solved numerically in the three-dimensional space before obtaining the h...

In magnetic resonance electrical impedance tomography (MREIT), we try to reconstruct a cross-sectional resistivity (or conductivity) image of a subject. When we inject a current through surface electrodes, it generates a magnetic field. Using a magnetic resonance imaging (MRI) scanner, we can obtain the induced magnetic flux density from MR phase images of the subject. We use recessed electrode...

INDEX OF SYMBOLS B Magnetic flux density (Tesla) c Speed of light ≈ 3×10 m/s Co Capacitance per unit length (F/m) Em Magnetic energy storage (Joules) H Magnetic field intensity (A/m) I Current (A) J Current density (A/m) K Surface current density (A/m) Lo Inductance per unit length (H/m) L Inductance (H) N Coil turns R Reluctance (A-turns/Wb) Φ Flux (Weber) λ Flux linkage (Weber-turns) εo Permi...

  The flux-pinning mechanism and activation energy of 10 wt % malic acid-doped MgB2 were investigated by measuring of the critical current density and resistivity as a function of magnetic field and temperature. A crossover field, Bsb, was observed from the single vortex to the small vortex bundle pinning regime. For the sintered sample, the temperature dependence of Bsb(T) at low temperature i...

Permanent magnet arrays have advantages for magnetic field generation over the traditional current based magnetic flux sources, such as electromagnets, in that they do not require a power supply and cooling system. Magnetic flux density above the magnetic remanence BR of the permanent magnet material can be achieved by arranging the permanent magnet segments in the form of hollow cylindrical sh...

electric and hybrid electric vehicles are attractive candidates for sustainable transportation due to its higher efficiency and low emission. the critical choice on the electric motors is its capability of motoring and regenerative braking characteristics. switched reluctance machines are viable candidate as with proper control and extended constant power range operation replacing the multi-gea...

Observations of quiet Sun from the Solar Optical Telescope/SpectroPolarimeter (SOT/SP) aboard the Hinode spacecraft would reveal the magnetic characters of the solar photosphere. By making use of the deep mode observations of three quiet regions, we have statistically studied the vector magnetic fields of solar granulation. More than 2000 normal granules are manually selected to form a sample. ...