Update on Q4 DSM/IRFU/SACM The HiLumi LHC Design Study (a sub-system of HL-LHC) is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement M. Segreti, J.M. Rifflet 3 July 2013

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

New porous cable insulation scheme (radial = 0.16 mm; azimuthal = mm) Classical MQ insulation thicknesses (radial = 0.13 mm; azimuthal = mm) 3 blocks (7-5-2 conductors) HX hole at 101 mm of the magnet center I nom = A; Collar µr = blocks (8-4-2 conductors) HX hole at 95 mm from the magnet center I nom = A; Collar µr = Harmonics (Units) b3b4b5b6b10b14b Harmonics were not optimized after having added the collar

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

Thermo-mechanical properties Due to the cable insulation creep after the collaring process, it is also assumed 20 % and 30 % losses of pre-stress in conductor blocks using the classic MQ and the new porous EI#4 insulation schemes, respectively

Mechanical results with MQ cable using the classical MQ insulation (Insulation thickness:radial= 0.13 mm azimuthal= 0.11 mm)

Coil azimuthal stress distribution (MPa) After collaring  θ max = MPa  θ mean = - 67 MPa At 2 K  θ max = - 52 MPa  θ mean = - 40 MPa At 110 % of I nom  θ max = - 63 MPa  θ mean = - 41 MPa

Coil Von Mises stress distribution (MPa) After collaring  VM max = 93 MPa At 2 K  VM max = 51 MPa At 110 % of I nom  VM max = 61 MPa

Coil displacement due to Lorentz forces at 110 % of I nom (µm) Coil azimuthal displacement δ θ max = 17 µm toward mid-plane Coil radial displacement δ r max = 27 µm toward outer radius

Mechanical results with MQ cable using the new porous EI#4 insulation (Insulation thickness:radial = 0.16 mm azimuthal= mm)

Coil azimuthal stress distribution (MPa) After collaring  θ max = MPa  θ mean = - 84 MPa At 2 K  θ max = - 63 MPa  θ mean = - 48 MPa At 110 % of I nom  θ max = - 72 MPa  θ mean = - 49 MPa

Coil Von Mises stress distribution (MPa) After collaring  VM max = 118 MPa At 2 K  VM max = 62 MPa At 110 % of I nom  VM max = 70 MPa

Coil displacement due to Lorentz forces at 110 % of I nom (µm) Coil azimuthal displacement δ θ max = 33 µm toward mid-plane Coil radial displacement δ r max = 42 µm toward outer radius

Summary of the main results at each step

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

geometric errors in the 24 blocks (inputs for the 500 ROXIE calculations) We do also for rms of 10, 20, 30, 40 and 50 µm For quadrupole magnet, the standard deviation of the normalized multipoles can be described by a power law σ(a n,b n ) = dαβ n

dalphabeta [µm][1/µm][-] Average Random in the 24 blocks of one of the double 90 mm aperture, R ref = 30 mm, I = A, with symetric yoke, with shrinkage, to compare with operating measurements dalphabeta [µm][1/µm][-] Average Random in the 24 blocks of the single 90 mm aperture, R ref = 30 mm, I = 1000 A, without yoke, without shrinkage, to compare with warm measurements

Thanks to Qingjin Xu and Xiaorong Wang for their help!

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

Yoke hole diameterHole vertical positionHarmonics (Units) for HX (mm)from magnet center (mm)b3b4b5b6b10b14b18 60 * Yoke hole diameterHole vertical positionHarmonics (Units) for HX (mm)from center (mm)B3b4b5b6b10b14b * b3 can be minimized by adapting the vertical position of the HX hole without changing the position of the conductor blocks i.e. the coil geometry  the final HX size can be decided later

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

Main goal of the coil end optimization : -The minimization of the mechanical stress on the cable i.e. minimization of the strain energy due to the winding process -The minimization of the integrated multipole coefficients along the coil end (this is harder to obtain with only one coil layer) -To limit the peak-field as possible if localized in coil ends to improve quench performance Use of ROXIE to design and to optimize the coil ends (3 D calculation and analysis take a lot of time)

integrated multipole coefficients along the coil return end b6 b10

1. Magnetic designs (90 mm aperture with one layer of MQ cable) using: the classical cable insulation the new porous EI#4 insulation scheme 2.Mechanical comparison of results obtained with the two schemes of cable insulation 3.Random field error analysis 4.Effect on harmonics of heat exchanger position (in the iron yoke) 5.Coil end design & optimisation 6.Protection (brief results)

Case 1: results obtained without dump resistor and with 0.016s delay quench-heater Results obtained from the protection software developped by P. Fazilleau

Case 2: results obtained with a 49 mΩ dump resistor and without quench- heater Results obtained from the protection software developped by P. Fazilleau

Case 3: results obtained with a 49 mΩ dump resistor and with 0.016s delay quench-heater Results obtained from the protection software developped by P. Fazilleau