Raymond Veness (CERN)
Issues Raised by the Design of the LHC Beam Dump Entrance Window
The LHC beam dump entrance window consists of a carbon-carbon composite structural sheet backed by a thin stainless steel foil for leak tightness. The design of this window has highlighted issues that merit further investigation. The use of the bulk coefficient of thermal expansion coefficient for the composite should be questioned where there is a significant temperature gradient between...
Markus BRUGGER (CERN)
Overview of FLUKA Energy Deposition and Design Studies for the LHC
In order to assess the energy deposition in sensitive LHC components, extensive simulations were performed with the Monte Carlo cascade code FLUKA. In many cases specialized solutions needed to be found, challenging in several aspects, i.e., from the calculation as well as from the design point-of-view. Depending on the problem, detailed geometrical implementations, an accurate...
Markus BRUGGER (CERN)
Generic studies of radioactivity induced by high energy beams in different absorber materials
A rigorous campaign of benchmark measurements for materials typically used at accelerators has shown the high accuracy of FLUKA calculations for isotope production and residual dose rates. Accurate estimates of both quantities are important during all phases of an accelerator, i.e., design, operation and decommissioning. A detailed implementation of geometries and accurate consideration of...
George SMIRNOV (CERN)
Studies of radiation effects on graphite collimator materials
The current status of the code development for simulating the structural damage of the graphite jaws of the LHC collimators produced by 7 TeV protons is presented. The technique, which is being developed in the framework of the Monte Carlo code FLUKA, combined with the results of experimental tests of carbon-carbon composite materials in radiation hard environment will be capable of...
Naeem TAHIR (GSI)
Alessandro DALLOCCHIO (CERN)
FE simulation of 450 GeV injection error test
Dynamic phenomena provoked by the rapid interaction of energetic particle beams with slender structures usually known as thermally induced vibrations are presented. Specific regard is given to the analysis of the accident case triggered by a beam injection error at 450 GeV, recently tested at CERN on LHC collimator prototypes. A simplified analytical method, which was previously...
Alexander RYAZANOV (KURCHATOV INSTITUTE)
Beam impact on collimator materials: Studies for LHC by Kurtchatov Institute
Theoretical models and numerical calculations are presented here to understand an influence of the impact of a 7 TeV proton beam on the physical-mechanical properties of collimator materials (C, Cu) used in the LHC. Here we develop the theoretical model for shock wave propagation and theoretical model for calculations of primary radiation damage formation including calculations of a...
Alessandro Bertarelli (CERN)
FE codes for thermo-mechanical analysis for Phase I collimation
The functional requirements of the LHC Collimators impose, for the start-up of the machine and the initial luminosity runs (Phase 1), a collimation system with a very high dimensional stability in nominal operating conditions, under considerable thermal loads and, at the same time, maximum robustness in case of accidental beam impacts. In order to meet these requirements and to optimize...
Nick SIMOS (BNL)
Experience with Implicit and Explicit codes in analyzing beam-induced thermo-mechanical shock
In an effort to extrapolate the interaction of intense proton pulses with materials to power levels beyond those achieved to-date in accelerators, computational schemes based on finite element formulation are being widely employed. While the long-term interaction between radiating particles and materials result in the degradation of the ability of a material to absorb the induced shock,...
Luca Bruno (CERN)
Numerical tools for the design of beam intercepting devices
Beam intercepting devices (collimators, targets, absorbers) capable of sustaining high-intensity beams are key elements to meet the future physics needs. The highly non-linear phenomena involved in their design study (cavitation, transient magnetic-hydrodynamic effects on liquid metal jets, phase change, fluid-structure interactions) require advanced simulation tools at the forefront of...
Rocio CHAMIZO (CERN)
Luca Massidda (CRS4)
Dynamic structural analysis of absorbers with spectral-element code ELSE
The dynamic structural behavior of beam diluter elements TCDS (LHC) and TPSG (SPS), protecting the extraction septum magnets in the event of an asynchronous firing of the extraction kickers, has been studied. The deposited energy densities, estimated by the high-energy particle transport code FLUKA, were converted to internal heat generation rates according to the time dependence of the...
Rüdiger Schmidt (CERN)