Author: Charles, T.K.
Paper Title Page
MOPC002 Flow Induced Vibrations of the CLIC X-band Accelerating Structures 65
 
  • T.K. Charles, K. Ryan
    Monash University, Melbourne, Australia
  • M.J. Boland
    ASCo, Clayton, Victoria, Australia
  • G. Riddone
    CERN, Geneva, Switzerland
  • A. Samoshkin
    JINR, Dubna, Moscow Region, Russia
 
  Turbulent cooling water in the Compact Linear Collider (CLIC) accelerating structures will inevitably induce some vibrations. The maximum acceptable amplitude of vibrations is small, as vibrations in the accelerating structure could lead to beam jitter and alignment difficulties. A Finite Element Analysis model is needed to identify the conditions under which turbulent instabilities and significant vibrations are induced. Due to the orders of magnitude difference between the fluid motion and the structure's motion, small vibrations of the structure will not contribute to the turbulence of the cooling fluid. Therefore the resonant conditions of the cooling channels presented in this paper, directly identify the natural frequencies of the accelerating structures to be avoided under normal operating conditions. In this paper a 2D model of the cooling channel is presented finding spots of turbulence being formed from a shear layer instability. This effect is observed through direct visualisation and wavelet analysis.