Calculation of the thermo-structural transient in LHC dipole at quench

Computations of the transient mechanical behavior of a magnet in the case of a sudden loss of superconductivity (quench) have been made. The time-dependent map of temperature in the cross section where the quench starts is computed using a new quench analysis program called QUABER. After having defined the geometrical configuration of the magnet, conditions close to the real situation in the Large Hadron Collider (LHC) machine have been simulated. The temperature distribution is used as input for the following steps of the investigation. The thermo-mechanical transient in the structure is analyzed by means of a finite element model approach. The results presented give predictions about the cycle of loads and stresses in the dipole during normal operation and in case of quench. The electrical insulation is shown to behave as a thermal barrier limiting the short-time heating of the collars to a few degrees. Stresses in the coils during the quench stay within the range of the normal working conditions