1 / 31

Upgrade phase 1: Energy deposition in the triplet

Upgrade phase 1: Energy deposition in the triplet. Elena Wildner Francesco Cerutti Marco Mauri. Outline. Baseline, IR1 and IR5 Some basic considerations The upgrade Phase I scenario Simulation results Continuation Conclusion. Work on the nominal insertion layout.

conley
Télécharger la présentation

Upgrade phase 1: Energy deposition in the triplet

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. Upgrade phase 1:Energy deposition in the triplet Elena Wildner Francesco Cerutti Marco Mauri Energy deposition, LIUWG, Elena Wildner

  2. Outline • Baseline, IR1 and IR5 • Some basic considerations • The upgrade Phase I scenario • Simulation results • Continuation • Conclusion Energy deposition, LIUWG, Elena Wildner

  3. Work on the nominal insertion layout • Energy deposition studies independently Fermilab, 2002 & CERN, 2007 (LHC report 633 and LHC note to appear) with MARS and FLUKA • In addition comparisons have been made on representative toy model • Agreement 5 % in coils 20% in iron • Studies so far up to D1 Energy deposition, LIUWG, Elena Wildner

  4. Models of baseline IR1 and IR5 Courtesy C. Hoa Liner in Q1 and MCBX of thickness 6.5 mm (stainless steel) Length 31 m Magnet apertures 70 mm Half crossing angle 142.5 mrad Energy deposition, LIUWG, Elena Wildner

  5. Heat load along the triplet, “nominal” To limit the peaks in the superconducting coils: our first objective Luminosity= L0 (1 *1034 cm-2s-1) Recommended limit Q1 Q2a Q2b Q3 Courtesy C. Hoa Energy deposition, LIUWG, Elena Wildner

  6. The scoring • Cable • We make the binning for the scoring so that it corresponds to a minimum volume of equilibrium for the heat transport (cable transverse dimensions, with a length corresponding to the twist pitch of the cable) • Total power deposited in the magnets • Important to know the volume of the magnet (the model has to be realistic) • The power deposited per meter of magnet • Azimuthal integration of the power in the longitudinal bins Important for results to know how this is calculated and choose correct bin size!!! Scoring volume: A*L Transverse area of cable (A) Length (L) 10 cm (twist pitch) Energy deposition, LIUWG, Elena Wildner

  7. Effect of Magnetic Field, nominal IR5 Energy deposition, LIUWG, Elena Wildner

  8. Q1,no TAS Q1, TAS 40 mm aperture Effect of the TAS ”Symmetric” upgrade layout Energy deposition, LIUWG, Elena Wildner

  9. Effect of Crossing Angle, nominal IR5 Total Peaks Energy deposition, LIUWG, Elena Wildner

  10. Basic considerations (summary) • Beam Pipe • The beam pipe between magnets shields the front face of the downstream magnet • The experimental vacuum chamber before the TAS has to be properly integrated • We do not include the experimental vacuum chamber before the TAS in our calculations yet • TAS • The TAS protects essentially the first quadrupole • Magnetic field • The magnetic field is driving the deposited energy • Mask • A mask outside the magnet aperture does not affect the energy deposited in the cable • Crossing angle • The effect of the crossing angle is smaller than 20% Energy deposition, LIUWG, Elena Wildner

  11. Positive particle + FDDF The layout, Phase I “Symmetric” TAS Q1 Q2a Q2b Q3 IP1 130mm 130mm 130mm 130mm 9.40m 7.80m 7.80m 9.40m 41 m LHC Project Report 1000: “A Solution for Phase-one Upgrade of the LHC Low-beta Quadrupoles Based on Nb-Ti”, J. P. Koutchouk, L. Rossi, E. Todesco Half crossing angle: 220 m rad, vertical For comparison: “Nominal” (L=L0) layout is about 30 m long. Energy deposition, LIUWG, Elena Wildner

  12. The Magnet/Field Model Cold Mass outer diameter 570 mm 4 X MQXC 130 mm Aperture 270 mm Courtesy: F. Borgnolutti Energy deposition, LIUWG, Elena Wildner

  13. The magnet ends • The magnets have in this first study the same length as the magnetic length: mechanical length = magnetic length • No coil ends are modeled (the same transverse layout over the whole magnet) • No 3D field or hard edge approximation Energy deposition, LIUWG, Elena Wildner

  14. Beam pipe dimensioning • Relation thickness (t) and diameter (D), valid for stainless steel: t = 0.0272D • Example for 130 mm aperture quads (3.5 mm is the gap between coil and beam tube): OD = 130 mm - 3.5 mm = 126.5 mm Thickness of beam pipe according to formula: t= 3.45 mm ID = 126.5 mm – 2*3.45 mm = 119.6 mm Energy deposition, LIUWG, Elena Wildner

  15. “Baseline”or “reference” case, no shielding Peak in coils Luminosity = 2.5 L0 Minimum thicknesses for mechanical considerations: Beam-Pipe 3.45 mm Beam-Screen 2 mm Ref. value for max energy deposition 4.3 mW/cm3 Q1 Q2a Q2b Q3 Continuous beam-screen and pipe, no experimental vacuum pipes Energy deposition, LIUWG, Elena Wildner

  16. Azimuthal heat deposition pattern, Q2a a = 180/16 Energy deposition, LIUWG, Elena Wildner

  17. Beam-screen, case 3mm W-liner OD = 119.6 mm – 2 * 0.7 mm – 2 * 3 mm = 112.2 mm ID = OD – 2 * 2 mm = 108.2 mm Liner Additional restriction on vertical aperture Necessary Gap 108.2/2 102.61/2 Beam-Screen thickness Energy deposition, LIUWG, Elena Wildner

  18. Liner dimensioning Old Capillary Position Beam-pipe and beam-screen as thin as mechanically possible! Magnet aperture 130 mm same in all 4 magnets. s Liner w a hmax = Di,CBT - 2*0.7-2*4.76 - 2*2.0 -2*s= Di,CBT - 14.92 - 2*s Di,BS = Di,CBT - 2*0.7-2*2.0 – 2*3.0= Di,CBT– 11.4 s= (Di,CBT /2 - 4.76/2-0.7)(1-Cos[a]) w= (Di,CBT /2 - 4.76/2-0.7)(Sin[a]) Width of liner: w - outer radius of Capillary = 22.2 mm - 4.76 mm Energy deposition, LIUWG, Elena Wildner

  19. Adding a liner along the Triplet Recommendation: 3 mm W shield up to Q2 Continuous beam-screen and pipe, liner also between magnets Energy deposition, LIUWG, Elena Wildner

  20. Liner not covering entirely gap Q1-Q2 Gap No shielding, only BS and BP Liner 3mm W Energy deposition, LIUWG, Elena Wildner

  21. Liner not covering entirely gap Q1-Q2 Shielding like for “nominal”: Peak due to 1.5 m “gap” Shield needed between magnets Energy deposition, LIUWG, Elena Wildner

  22. Total heat load in magnets Energy deposition, LIUWG, Elena Wildner

  23. Total heat load Integration over 10 cm longitudinal (z) bins Q1 Q2a Q2b Q3 Energy deposition, LIUWG, Elena Wildner

  24. Between the Q1 and the Q2 magnets • Critical region, must be shielded: • Coil end • BPM aperture 1.4 cm stainless steel (checked case) Nominal Layout Energy deposition, LIUWG, Elena Wildner

  25. TAS opening • The TAS opening has been taken as 55 mm Energy deposition, LIUWG, Elena Wildner

  26. TAS, lateral and backwards scattering Normalization (Lupgrade = 2.5 L0) Energy deposition, LIUWG, Elena Wildner

  27. TAS, mechanical considerations Fluka - > Ansys Luminosity: 2.5 1034 cm-2 s-1 TAS aperture: 55 cm Total power in TAS: 300 W Peak: 131 mW/cm3± 7% Energy deposition, LIUWG, Elena Wildner

  28. Continuation • Choice of pipe sizes and absorbers for next iterations • Model of the region between Q1 and Q2a to be refined • 3D field of coil ends, mechanical lengths • Corrector magnets to be implemented • Including D1, TAN, D2 and Q4 • Detailed experimental pipes also before TAS • Mechanical analysis of the TAS • Detailed study on the beam particle distributions at the collisions • Ions Energy deposition, LIUWG, Elena Wildner

  29. Conclusion • The beam-pipe and the beam-screen thicknesses are enlarged (aperture increase): decreases energy deposition in coils! • For good coil protection, we propose to add a 3 mm tungsten sheet (or equivalent) around the beam screen up to the entry of the second quadrupole. • We need to design detailed shielding in the region close to the beam-pipe between Q1 and Q2a, according to point 2 above (BPM, RF-conncetion, interconnects…) Energy deposition, LIUWG, Elena Wildner

  30. Thanks to Alessio Mereghetti Joined team from 01/01/2008 • R. Ostojic • V. Baglin • S. Fartoukh • M. Karppinen • S. Sgobba • L. Tavian • And others… Energy deposition, LIUWG, Elena Wildner

  31. Comparison, smaller aperture TAS The smaller TAS aperture shields better the entrance of the first quad The effect of 3 mm SS between magnets is important for peak in second quad Energy deposition, LIUWG, Elena Wildner

More Related