Toshie Takeuchi

Method for analyzing 3-D magnetic field in linear actuator using nonconforming mesh with edge elements

A method for analyzing three-dimensional (3-D) magnetic field in a model including moving parts, such as linear actuator, was developed by using a nonconforming mesh with edge elements. In this method, the meshes for moving and nonmoving parts are generated individually, and they are overlapped together at an arbitrary position. Then, the magnetic field analysis is carried out by using the nonconforming technique with interpolation. It is shown that the proposed method is useful for a dynamic analysis of a 3-D actuator model.

Construction and beam experiment of a compact storage ring at MELCO

A compact storage ring has been developed for industrial research such as x‐ray lithography and material analysis. This machine is of a racetrack type with two superconducting bending magnets and only two normal conducting quadrupole magnets. The circumference is as short as 9.2 m. One quadrupole magnet per cell contributes to making the smaller machine. The injector is a synchrotron, and a full energy injection of 600 MeV is performed. The bending magnets excite a field of 3.5 T, and are operated in a persistent current mode. A decrease in a coil current is ΔI/I<3×10−3/year. The helium consumption is as low as 2 l/h for two magnets. An iron shield of the magnet decreases a leakage flux to a terrestrial level at a point 3 m from the magnet. A beam current of 380 mA has been stored with no beam instability in spite of there being no correction of the chromaticities. Beam emittances were obtained from measured beam sizes and were in good agreement with calculated values. The coupling coefficient ey/ex is ca...

A Conceptual Design of a Superconducting Magnet for a Magnetic Levitated Train Using a High Tc Oxide Superconducting Wire

A conceptual design of a superconducting magnet for magnetic levitated train (MAGLEV) using a silver sheathed wire of high Tc oxide superconductor is studied. In the conceptual design, the superconducting magnet is operated by persistent current at 20K. The efficiency and the reliability of refrigerator are high at 20K. The critical current density of 6x104 A/cm2 is required at 5T for the conductor. The coil is stable against disturbance, because the minimum quench energy is large. On the other hand, the quench propagation velocity of the coil is low. The coil needs active quench protection.