Thermomechanical response of Large Hadron Collider collimators to proton and ion beam impacts
Thermomechanical response of Large Hadron Collider collimators to proton and ion beam impacts
复制标题
大型强子对撞机准直器对质子和离子束撞击的热机械响应
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
N. Sammut
中科院分区：
文献类型：
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作者：
M. Cauchi;R. Assmann;A. Bertarelli;F. Carra;F. Cerutti;L. Lari;S. Redaelli;P. Mollicone;N. Sammut
CERN大型强子对撞机(LHC)旨在加速高能质子和重离子的碰撞并使其发生碰撞。两种情况下都可能发生光束直接撞击准直器的事故。LHC准直系统是为满足高强度质子束的苛刻要求而设计的。尽管质子束的束流功率是标称的LHC铅离子束的100倍，但与质子相比，由于不同的粒子-准直器相互作用机制导致的离子损失，可能会出现特定的问题。本文研究和比较了离子束和质子束对准直器的直接影响，特别是由钨重合金INERMET 180制成的三级准直器(TCTS)。最近对这种合金在不同温度下的静态和动态加载条件下的力学行为进行了测量，并用于现实地估计准直器对束撞击的响应。利用这些新的测量结果，本文提出了一种数值有限元方法。在弹塑性域中进行了连续的快速瞬变热结构分析，以评估和比较TCTS在涉及质子和重离子束碰撞的临界束载荷情况下的热机械响应。
The CERN Large Hadron Collider (LHC) is designed to accelerate and bring into collision high-energy protons as well as heavy ions. Accidents involving direct beam impacts on collimators can happen in both cases. The LHC collimation system is designed to handle the demanding requirements of high-intensity proton beams. Although proton beams have 100 times higher beam power than the nominal LHC lead ion beams, specific problems might arise in case of ion losses due to different particle-collimator interaction mechanisms when compared to protons. This paper investigates and compares direct ion and proton beam impacts on collimators, in particular tertiary collimators (TCTs), made of the tungsten heavy alloy INERMET 180. Recent measurements of the mechanical behavior of this alloy under static and dynamic loading conditions at different temperatures have been done and used for realistic estimates of the collimator response to beam impact. Using these new measurements, a numerical finite element method (FEM) approach is presented in this paper. Sequential fast-transient thermostructural analyses are performed in the elastic-plastic domain in order to evaluate and compare the thermomechanical response of TCTs in case of critical beam load cases involving proton and heavy ion beam impacts.