LBNE Dipole Corrector IDS Design Review Sasha Makarov

LBNE Dipole Corrector (IDS) Design Review Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) IDS Dipole Design Specification: Magnet gap Magnet core length Dipole strength at 15 A DC Magnetic field strength (max peak at 30 A) Integrated field strength (max peak at 30 A) Magnet aperture (h x b) Good field region size Good field deviation at max field Core type Cooling type Max temperature of magnet surfaces at 15 A DC Max magnet weight Max magnet cross section (H x B x L) 3” 12” 0. 075 T-m 0. 365 T 0. 150 T-m 3” x 5” 2” x 2” < 0. 75% Laminated Air cooled 60°C 500 kg 24” x 17. 25” Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) IDS Dipole Design Constrains: The magnet concept for the LBNE Trim Dipole IDS is the same as was used for the Fermilab Main Injector Trim Dipoles (IDH). Both magnets are air cooled magnets, and the outer coil and core surfaces temperature shall not exceed 60° C (a service safety limit). The IDS magnet has a larger gap, and it is stronger than IDH trims, but it shall have the same core length and similar overall length. The IDS trim can be powered with up to 30 A current, but the RMS current shall not exceed 15 A to avoid the magnet outer surfaces overheating. Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) IDH Dipole Trim Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) The IDH trim dipole for MI was designed in 1995 at Fermilab by Youry Terechkine (magnet calculations) and me (mechanical design). Many vertical cooling channels were created in the magnet core in order to increase the efficiency of core cooling. These channels not only significantly increase the core outer surface, but also create a “chimney effect” improving the heat dissipation. The IDH magnet became a very popular trim dipole at Fermilab, so now we have a lot of modifications of this magnet: IDHE, IDHKB, IDHKR, IDHKW, IDHR, IDHWA. These modifications provide different magnet orientation, different magnet gap, and some were equipped with additional water cooled steel plates attached to the core in order to satisfy to different power requirements in different parts of Fermilab complex. Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) In spite of such a large variety of the IDH type trim dipoles, the LBNE requirements on the higher field strength at a larger magnet gap and a ban on using of water for the magnet cooling initiated a completely new magnet design (still using the IDH trim dipole concept). The possibility of magnet air cooling and max magnet weight were the driving criterions of this new design. It was clear that in order to meet the magnet spec, a new magnet shall have more copper in the winding and significantly larger core cross section. Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) IDS Magnet Parameters Magnet Gap Magnet Good Field Region Core Length Max Magnet Length Integrated Field Strength (max) IDH Magnet Parameters 3” 2” x 2” 17. 25” 0. 15 T-m Magnet Gap Magnet Good Field Region (H x B) 12” Max Magnet Length 17” Integrated Field Strength (max) 928 Number of Turns Magnet Inductance 1. 1 H Magnet Inductance AGW #8 1. 5” x 3” Core Length Number of Turns Conductor (copper, square, heavy ML coated) 2” Conductor (copper, square, heavy ML coated) 0. 09 T-m 812 800 m. H AGW #10 Coil Resistance (at 20° C) 1. 7 Ω Coil Resistance (at 20° C) 2. 4 Ω Max Current 30 A Max Current 15 A Magnet Weight 1100 LBS Magnet Weight 400 LBS Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) The IDS magnet design is universal: the same magnet can be used for both horizontal and vertical beam bend with the possibility of installation on the same magnet stand. The IDS magnet cross section is significantly larger than for the IDH magnet: 50% larger magnet gap, 1/2” wider pole (to provide required field uniformity), more copper volume (to reduce the power losses in the coil), and greater core outer surface (to increase the heat dissipation and meet the max magnet temperature restrictions at 15 A current). However, the total magnet weight is within specified 500 kg. Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) The magnet winding contains two identical coils (464 turns each: 29 layers x 16 turns per layer), wound from square AGW #8 solid heavy ML insulated copper wire, and connected in series. Coils are vacuum impregnated with epoxy, and glued into core for better thermal conductivity between coil and core. Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) The magnet has laminated core assembled from nonsymmetrical laminations which allows to provide vertical channels on each side of magnet core for the “chimney air cooling effect” at any magnet orientation. Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) IDS Magnet Lamination Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) The lamination drawing from above demonstrates the shape and critical dimensions which provides required by spec field strength and quality and being properly stacked provides the magnet cooling at specified 15 A DC current. The magnet also can be powered up to 30 A current without significant saturation, which ensures a required field quality, but the RMS current shall be kept within 15 A, or the magnet shall be shielded to prevent people from touching any of magnet’s surfaces during operation. For now the type of lamination was copied from the IDH type of magnet. The thickness of lamination is 0. 025”. C-3 coating on laminations allows insulate laminations from each other, which is critical for fast ramped magnet (I am not sure if we need this here). This approach requires to glue laminations in the core (a very messy process, and if possible I would prefer to avoid this). Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) Magnetic Field in the Core at 30 A Magnetic Field Distribution in the Magnet Gap Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) At 30°C ambient temperature At 40°C ambient temperature Coil and Core Max Temperature vs Time at 15 A DC Current Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) Coil and Core max temperature vs time at 30 A DC current and 40°C ambient temperature Sasha Makarov 10/29/2014

LBNE Dipole Corrector (IDS) Summary on IDS Magnet: 1. The new air cooled IDS Trim Dipole Magnet for the LBNE was designed, and it meets the magnet specification. 2. The magnet is universal for Horizontal Trim and Vertical Trim orientation, and can be installed on the same stand. 3. A few small details on the magnet operation regime and integration with support system need to be verified before ordering parts (this might affect the production process). 4. A prototype of this new type of magnet shall be built and tested at MTF before ordering parts for production. Sasha Makarov 10/29/2014