1 / 19

Design Study of the PRISM-FFAG Magnet with inter-pole

Design Study of the PRISM-FFAG Magnet with inter-pole. S. Nakaoka Osaka Univ. Contents. Outline of PRISM-FFAG Magnet Principle of Anisotropic inter-pole Effects of Anisotropic inter-pole Prototype test of inter-pole Summary. z. r. θ. Outline of PRISM Magnet. Aperture size :

donar
Télécharger la présentation

Design Study of the PRISM-FFAG Magnet with inter-pole

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Design Study of the PRISM-FFAG Magnet with inter-pole • S. Nakaoka Osaka Univ.

  2. Contents • Outline of PRISM-FFAG Magnet • Principle of Anisotropic inter-pole • Effects of Anisotropic inter-pole • Prototype test of inter-pole • Summary

  3. z r θ Outline of PRISM Magnet • Aperture size : • 110 cm (horizontal) • 30 cm (vertical) • Gradient of magnetic field is produced by main pole • Anisotropic inter pole is used

  4. What is Anisotropic Inter-Pole? • Structure • Layers of ferromagnetic and paramagnetic material • Advantage • Fringe field distribution become uniform at different r-position. • Smoothing of fluctuation for field distribution caused by trim coil

  5. Why is “Anisotropic” Inter-Pole? • Boundary condition of surface in magnetic material • Vertical • Horizontal z μ1 divB=0 Bz1=Bz2 (B1cosθ1=B2cosθ2) θ1 rotH=0 Hr1=Hr2 (H1sinθ1=H2sinθ2) r μ2 Br2 =(μ2/μ1)Br1 θ2 If μ2 is large ,magnetic flux which is produced by main pole flows rapidly and magnetic field in gap becomes flat. So to reflect gradient of magnetic field produced by main pole , μ2r 〜μ1r in horizontal direction. μ2r: large μ2r：small

  6. Why is “Anisotropic” Inter-Pole? • And more… • In vertical Bz1=Bz2 ,so magnetomotive force is not loss. • And horizontal permeability is not unity , so magnetic flux is slightly flowed and fluctuation of magnetic field which is caused by trim coil or polebecomes smooth. z μ1 θ1 r μ2 θ2 μ2：small μ2: large

  7. Effect of inter-pole 1 • Uniform fringing magnetic field distribution in different r With inter-pole Without inter-pole 3D Calculation by TOSCA

  8. Effect of inter-pole 2 • Improvement of field fluctuation of local k caused by trim coils With inter-pole Without inter-pole 2D Calculation by PANDIRA

  9. Prototype test of Inter-Pole • Purpose • To check 3D TOSCA simulation for magnetic design • To confirm effects of inter-pole • Detail • Using Ushiwaka magnet (at KEK). • Do 3d mapping of magnetic field. • Preparing additional pole , by which gradient of magnetic field is produced. • Preparing several pitch which is thickness of a layer of inter-pole.

  10. Prototype Inter-Pole with Ushiwaka

  11. Prototype Inter-Pole with Ushiwaka

  12. Prototype Inter-Pole with Ushiwaka

  13. Prototype Inter-Pole with Ushiwaka

  14. Summary • Anisotropic inter-pole is used, which have following merits • Make uniform magnetic field distribution at fringe • Damp the undulation of local k due to trim coils • Now we are preparing prototype test of inter-pole

  15. Calculation Results Magnetic field distribution

  16. Estimate of accuracy 1 • Comparing irregular magnetic field with normal magnetic field In case of lowering inter-pole 1cm all over

  17. Estimate of accuracy 2 • Comparing irregular magnetic field with normal magnetic field In case of extended inter-pole 1cm in vertical direction

  18. Estimate of accuracy 3 • Comparing irregular magnetic field with normal magnetic field In case of deviated 1 cm in horizontal direction

  19. Estimate of accuracy 4 • Comparing irregular magnetic field with normal magnetic field In case of B-H curve of inter-pole uneven

More Related