Risto Nousiainen HIPs contribution SUPPORTING SYSTEM Structure support

Risto Nousiainen, HIP’s contribution SUPPORTING SYSTEM Structure support Input from H. Mainaud-Durand, N. Gazis, A. Samoshkin Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Introduction and Content • Scope of the supporting system • Baseline support – – Drive Beam & Main Beam supports Horizontal space available for the supports Module / Girder length Girder design • Highlights linked to supporting system • Alternative support concepts (common ideas of many people) – 3 alternatives shown • Conclusions • (Extra slides) Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Scope of the supporting system • • • ACs PETS DB Quadrupole Loads Various systems PETS ACs DB Quadrupole Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Baseline support What is the baseline support Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Baseline support From supporting point of view movers are rods (actuation omitted) Min 12 spherical joints In 6 rods 2 rods for girder joint; 4 rods for ground support Requirement: 1 µm accuracy Courtesy of H. Mainaud-Durand et al. Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Support kinematics Illustration ≈ However, baseline is less bound in longitudinal direction which is good for the snake “active end of a girder” “passive end of a girder” Girder support illustration (still longitudinal direction free) Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Space available for the supporting system Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Girder length • Girder will be done as long as technically feasible, currently that is 2 m for baseline (girder length can be altered in steps of 1 or 2 m) • N. Gazis is working on material selection and design of girder 320 x 150 x L with wall thickness of 50 mm Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Girder design R. Nousiainen on behalf of N. Gazis Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT This work is part of N. Gazis Ph. D Thesis for the NTUA 28/02/2021

Introduction • Estimation for the module weight • Weight distribution for MB type 0 (also available for other types): Type Total Weight [MB+DB] (kg) 0 1800 1 1600 2 1600 3 1600 4 1550 320 x 150 x L with wall thickness of 50 mm Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Baseline material Si. C can be produced in shapes and cross sections with several ways: 1) From Si. C powder, being densified by hotpressing with the addition of Al 2 O 3, Y 3 O 3, Ca. O at temperatures of 1700⁰C-1900⁰C (particle size of 90 nm) 2) From Liquid Phase Sintering at low temperature (particle size of 100 nm) 3) From Chemical Vapor Deposition, with various methods (atmospheric pressure, low-pressure, etc) Contacting of companies for the fabrication method ongoing Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Static condition girder simulations for Si. C 1 st conducted simulations (available for all module types) MB Si. C 4, 7 µm Steel 22, 4 µm DB Si. C 3, 8 µm Steel 19, 4 µm Currently weight on the MB girder is higher Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Future work • Material analysis • Fabrication technique analysis for the options • Definition of girder geometry / Engineering design for the girder • Including damping behavior in the design *Baseline Material is Sic Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Conceptual Simulation for baseline support To understand how the baseline supporting system behaves Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Baseline support simulation “Supporting point of view” • How does a snake behave ? – a modal analysis might bring insight how the supports tend to move in time domain • 1 st approach, a shell element model – Computation is light, but idealization heavy • Baseline materials Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Idealisation All structural parts are bonded with line-line contacts (to sustain linear model) “Supporting point of view” Linear rod modeling: With “spring” idealisation Normal stiffness = EA/L One of the heaviest idealisations apart from the use of shell elements for relatively thick shells Support rods Φ 60 mm (steel) Linkage rods Φ 30 mm (steel) Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Boundary conditions Meshing SHELL 181 Gravity is the only loading condition Large wall thicknesses. . . Element is optimal for thin or moderate Shell thickness… Fixed to ground Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT But results provide good insight on the overall behavior 28/02/2021

Results Structural – 10 µm 2 nd Mode Raises question if the stiffness decays when increasing number of girders Perhaps not yet a correct shape due to idealisation Modes’ Hz values not relevant in this simulation 1 st Mode Lateral stiffness will be an important issue Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Conceptual simulation on AS structure’s thermomechanical behavior To understand better how the baseline AS fiducialisation behaves Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Introduction • Background • We have a baseline for the installation and building up of the alignment references for pre-alignment before the operation of accelerator • Behavior of the AS has been estimated via FE Analyses in steady state conditions during operation • Question? • What happens between pre-alignment and operation during conditioning, when the temperature of the supports increases roughly by 5 -10 °C? • Objective • On what level do pre-alignment references sustain accuracy with regards to accelerating structures? Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

MB RF structure support • Accelerating structure, support and alignment references need to be integrated in the simulation Module design FE idealisation V-Support Girder is omitted in the simulation Models have same dimensions Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 2 D - simulation 28/02/2021

Result Vector calculation (sum the movements of sensor and AS center in one vector) yields the relative movement): We obtain 26 microns Cu OFE, Invar steel, ref. temperature 25 ºC Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT

Highlighted topics for the RF structure supporting system Keypoints being looked at momentarily relating to supporting system Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Highlighted topics • Cradle connection, pre-alignment system and the linkage of fiducialisation to supporting system – H. Mainaud-Durand • Beam parameters of drive beam require continuous contact through the beam interconnections. Drive beam line interconnections - C. Carion • Accelerating structure support is exposed to high temperature variations while the position of the beam line should be sustained within few µm and the sufficient stiffness of the supports should be maintained regardless to many integration constraints (such as vacuum) • Girder material affects the concept of RF structure fidusialisation through thermal behavior and flexibility of production methods. Also girder design shall provide sufficient interfaces for items such as alignment, installation and fiducialisation equipment – N. Gazis • Supporting system for special type modules • Overall weight of the RF structure support + RF network including girder has an upper limit due to linear movers Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Alternative supporting concepts “Supporting point of view”, contribution and input from many colleagues Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Snake support, bearing contacts Contact surface sphere Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Uncoupled support Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Single girder • ACs & PETS on same support, relative alignment for DB Quadrupole Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Conclusions • Baseline supporting system is under development and continues • Simulation conclusions – Continue girder development and include time domain in simulations – Develop methods for increasing lateral stiffness that are in compliance with baseline’s constraints – Development needed to sustain µm alignment for the AS with respect to sensors • Material – Continue Si. C implementation for the girder – Conduct a material selection study for the girder • Detailed design work will be done in collaboration with SU team and EN-MME • Alternatives also considered and compared against baseline – Work to be continued • Thank you!! Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Extra slides Line for ”balanced” lateral stiffness in vertical direction = C. o. G. = center of gravity Where x = 0 = optimal against inertial exitations ”Structure” Inertial exitations affect at c. o. g y ”Structure support” x Line for ”balanced” lateral stiffness in vertical direction ”Girder” z ”Supports” Maximize ~ z / y to minimize structural amplification and to improve lateral stiffness Minimize x while maximize lateral stiffness/weight Weight = overal weight of structures, girder etc. Lateral stiffnes = overall stiffness of the structures, girder etc. (Current: ~600 mm / ~300 mm = 2) Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Snake support, bearing contacts + relaxed weight limit - Clearances in the bearings - Line or point contacts (? ) àReduces stiffness In ro p l a iti s n & co s + Shorter “lever arms” because of smaller radius of bearings (compared to linking rods) - Eventually hard to totally avoid sliding friction Contact surface sphere Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021

Alternative supports • Electronically controlled snake – – Each girder sits on its own support Support positions free in longitudinal direction Continuity of beam line provided by reference measurements More data acquisition but girder length could be extended. ! DB continuity + no such weight limit ! Clearances in the bearings + longer girder ? Installation + Independent alignment Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT In pro ti ial s n & co s 28/02/2021

Single girder • ACs & PETS on same support, relative ros p l a Initi alignment for DB Quadrupole • ! Main beam quadrupoles • ! Drive beam continuity • ! Coupled beams • + Simplification for RF network • + No weight limit • + Longer modules than current baseline • ! Relative measurements needed for modules • + Facilitates transportation Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT s n & co 28/02/2021

Activity scheme for the different subsystems Risto Nousiainen, CERN BE-RF – Helsinki Institute of Physics – VTT 28/02/2021