Type IV Cryomodule (T4CM) Vibration Analysis Update

January 23, 2007

Mike McGee

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

DESY Cryomodule Measurements

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

Courtesy of DESY

ANSYS Model Validation

Mike McGee, 23 Jan 2007

Applying Harmonic Study (involving measured frequencies & displacements) using CMS Method

Using DESY measurement (as input) and comparing ANSYS output to corresponding (transfer function) DESY measurement

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

DESY Measurement Transfer Functions

Mike McGee, 23 Jan 2007

2) Vacuum Vessel Top vs HeGRP

1) Ground vs Vacuum Vessel Top

3) HeGRP vs Quad

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

TTF Single ANSYS Model Applied

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

Example: Transfer function between HeGRP and Quad

Consider the DESY vertical measurement, by applying sine wave input with displacement (amplitude) at specific frequencies.

Courtesy of DESY

Vertical Excitation & Response

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

Correlation Area

Two signals can be correlated:

Courtesy of DESY

ANSYS TTF Model Results

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

ANSYS model predicts the DESY measurement to within ~ 30% in most cases

0.01

0.1

10 12 14 16 18 20

HeGRP vs Quad (Vertical)

DESY (measured)2% damping ANSYS (predicted)

Am

plit

ude

(m

icro

n)

Frequency (Hz)10.1 Hz 18.5 Hz12.5 Hz

24%

28%

34%

Resonant frequencies found using modal analysis

Courtesy of DESY

TTF Modal Shapes

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

0.01

0.1

10 12 14 16 18 20

HeGRP vs Quad (Vertical)

DESY (measured)2% damping ANSYS (predicted)

Am

plitu

de (

mic

ron)

Frequency (Hz)10.1 Hz 18.5 Hz12.5 Hz

Courtesy of DESY

Transverse Excitation & Response

Mike McGee, 23 Jan 2007

Correlation Area

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

Modal Shapes of Resonant Frequencies

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

0.0001

0.001

0.01

0.1

1

4 6 8 10 12 14

HeGRP vs Quad (Transverse)

DESY (measured)2% damping ANSYS (predicted)

Am

plit

ud

e (

mic

ron)

Frequency (Hz)

8.2 Hz10.5 Hz 12.5 Hz

A very weak correlation transversely

Courtesy of DESY

Model Improvement and FurtherMeasurement

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

Slight damping initially considered in ANSYS model

Promising prediction of actual DESY vibration measurements have been realized, however continued measurements are needed

Ringing measurements at DESY are needed to define system damping estimate

Modal Analysis (fixed-fixed) Summary

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

Lowest (fundamental) frequency vertical with longitudinal mode shape is not present.

T4CM TTF

f (Hz) Modal Shape f (Hz) Modal Shape

--- - - - 10.1 Vertical w/ Longitudinal

12.7 Transverse Pendulum 12.4 Transverse Pendulum

16.3 Transverse S-shape 15.7 Transverse S-shape

17.9 Transverse S-shape 19.2 Transverse S-shape

Courtesy of DESY

3-in-Series w/ ends: Fixed-Fixed

Mike McGee, 23 Jan 2007

TTF Model T4CM Model

12.7 Hz12.4 Hz

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

Mike McGee, 23 Jan 2007

TTF Model T4CM Model

3-in-Series w/ ends: Fixed-Fixed

15.7 Hz 16.3 Hz

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

Mike McGee, 23 Jan 2007

TTF Model T4CM Model

3-in-Series w/ ends: Fixed-Fixed

19.2 Hz 17.9 Hz

3rd T4CM Meeting at INFN-Milan

Courtesy of DESY

Fermilab Website

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan

ANSYS Results given in picture and movie files

ANSYS Input Code files

Measurements

Future Work

Perform more specific vibration measurement on TTF cryomodule at DESY

Begin Sensitivity Studies using T4CM model

Mike McGee, 23 Jan 20073rd T4CM Meeting at INFN-Milan