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IDup Date Author Type Category Subject Text Attachments
  51   Tue Jul 9 14:45:04 2013 Emory BrownOpticsGeneralMeshing error when varying geometryI tried removing the constraints and applied
force and was able to get close to the same
frequencies for the butterfly modes as the
 Eigenfrequency.png 
  52   Wed Jul 10 14:15:20 2013 Emory BrownOpticsGeneralComparison of Umax and the frequency of the lowest eigenmode against ratioR I was able to run the looper program
designed last week over the interval ratioR=[0.5,
0.9] with a step size of 0.01 and obtained
 UmaxValuesVsRatioR.pngFrequencyLowestEigenmodes.pngdata.tar.gz 
  53   Wed Jul 10 17:52:18 2013 KojiGeneralGeneralHow to force time steps for a time dependent simulationA common trap in COMSOL:
When you run a time series simulation,
COMSOL tries to be "clever" by
  
  54   Thu Jul 11 19:16:12 2013 Deep ChatterjeeGeneralGeneralTE noise problem - Matlab scriptThe present aim is the calculation of the
TE noise like Liu and Thorne. Although, the
results of Liu and Thorne are for the case
 TE_model.malmost_infinite_2D_axisym_TE_4.m 
  55   Fri Jul 12 00:09:17 2013 Emory BrownOpticsGeneralAnalysis of substrate Brownian noise in a silicon test mass with changing ratioR value I performed the same analysis we
previously did on a test mass made of silicon
(using the built-in silicon within COMSOL)
 SiliconEigenfrequencyPlot.pngUmaxPlotSilicon.pngSilicon.tar.gz 
  56   Fri Jul 12 00:31:11 2013 Emory BrownOpticsGeneralReversed face mirror design We had noticed that when we ran an
eigenfrequency analysis, there was often
a node (see attached screenshot) on the face
 node.png 
  57   Fri Jul 12 19:43:32 2013 Deep ChatterjeeGeneralGeneralTE noise problem - Matlab script

    

       
            
 codes_TE_calc.zip 
  58   Sun Jul 14 15:13:46 2013 Deep ChatterjeeGeneralGeneralTE noise problem - Matlab script

    

       
            
 codes_TE_calc_(2).zip 
  59   Mon Jul 15 13:14:30 2013 Emory BrownOpticsGeneralUmax curves for varying height test masses I ran sweeps over the ratioR range
from 0.5 to 0.9 for test masses with modified
height, and thus mass, which were otherwise
 MassComparison.png 
  60   Mon Jul 15 16:05:29 2013 Deep ChatterjeeGeneralGeneralTE noise problem - Matlab script

    

       
            
 codes_TE_calc.zipJul_15.bmp 
  61   Tue Jul 23 18:26:04 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noiseIn this post I report of the results of
TE noise simulated by COMSOL for the TE noise
of Infinite test masses.
 Jul_23.bmpTE_calc_Jul23.zipJul_23.eps 
  62   Tue Jul 23 20:53:37 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  63   Tue Jul 23 20:53:37 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  64   Tue Jul 23 20:53:37 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  65   Tue Jul 23 20:53:37 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  66   Tue Jul 23 20:53:37 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  67   Tue Jul 23 20:53:37 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  68   Tue Jul 23 20:53:45 2013 Deep ChatterjeeOpticsGeneralComparison between Liu and Thorne Results and COMSOL results for TE noise

    

       
            
 Jul_23_bettermesh2.eps 
  69   Wed Jul 24 21:08:24 2013 Deep ChatterjeeOpticsGeneralTR results for different dimensionsIn this post I simulate the procedure of
calculating the TR noise for finite cavities
as proposed by Heinert and check for a
 Jul24.pdfJul24_acalc.pdf 
  70   Thu Jul 25 11:36:17 2013 ranaOpticsGeneralTR results for different dimensions 
 PDF
  
  71   Thu Jul 25 13:21:46 2013 Deep ChatterjeeOpticsGeneralTR results for different dimensions

    

       
            
 Jul_25.pdf 
  72   Thu Jul 25 15:54:58 2013 Deep ChatterjeeOpticsGeneralTR results for different dimensions

    

       
            
 Jul_25_1.pdfJul_25_2.pdfrelative_plot.pdf 
  73   Mon Jul 29 22:42:57 2013 Deep ChatterjeeOpticsGeneralAvoiding transient solutions in the Computation of TE/TR noiseAn error was being encountered in the computation
of the TR noise lately. It was observed that
while running the simulations in the case
 Jul29_2.pdf 
  74   Wed Jul 31 15:39:11 2013 Deep ChatterjeeOpticsGeneralFirst try with paramter optimization for TE and TR noise profilesAfter the simulations have been found to
match to a fair extent with the analytic
results by Heinert and Liu and Thorne, the
 Jul31_param_opt.pdf 
  75   Thu Aug 8 17:17:19 2013 Deep ChatterjeeOpticsGeneralSomething like cancellationFor the material parameters of Sapphire
at 300K, the TE and TR Noise profiles, though
not very close, lie close to within an order
 suspected_cance_AUg8l.pdf 
  76   Mon Sep 16 10:07:32 2013 EvanGeneralConfigurationCOMSOL 4.3 on the OS X command lineIf you're running Matlab scripts that iterate
over simulation parameters (à la Tara),
  
  77   Wed Nov 13 23:55:44 2013 Chris CousteOpticsAnalysisOptical Mount Vibrational AnalysisProject: Vibrational Analysis of Optical
Mounts
Goal: Use COMSOL to run finite element
  
  78   Mon Nov 18 15:56:59 2013 Chris CousteOpticsAnalysisRepresentative ModelsThe simpler models of the optical mounts
are finished, they will be run through the
comsol analysis software soon.
 Custom_Closed.JPGcustom_open.JPGStock_Closed.JPGStock_Open.JPG 
  79   Fri Nov 22 21:04:53 2013 Chris CousteOpticsAnalysisanalysis The analysis is making nice eigenmode
and stress mode models, but the displacement
experiment needs work. Should be fixed by
  
  80   Fri Jan 24 17:26:38 2014 Chris CoustéOpticsAnalysisMount Analysis Functional! The comsol eigenmode analysis is
complete, and the only thing left to do on
this part of the project is to run the analysis
  
  81   Sun Feb 16 21:10:56 2014 Chris CoustéOpticsAnalysisOptical Mount data compilation 1: Aluminum The time is finally here! this is
the highest displacement of each mount in
its lowest few eigenfrequencies, using 6061
 aluminum2.pngaluminum3.png 
  82   Thu Apr 17 16:52:09 2014 EvanGeneralCharacterizationInterpreting logfiles and picking a solverHere are two entries by Walter Frei on
the Comsol blog that I've found useful.
Solving
  
  83   Sun Jun 22 23:44:56 2014 Sam MooreOptics Going through Heinert's 'TR noise of cylindrical test masses' paperAt this point, my are goals are to 1) convert
the time-dependent heat equation into stationary,
complex form, 2) use the Levin approach to
  
  84   Mon Jun 23 11:40:17 2014 Sam MooreOptics Going through Heinert's 'TR noise of cylindrical test masses' paper

    

       
            
  
  85   Mon Jun 23 16:10:17 2014 Matt A.Optics Going through Heinert's 'TR noise of cylindrical test masses' paper

    

       
            
 SamEq1.pngSamEq2.pngSamEq3.pngSamEq4.png 
  86   Tue Jun 24 14:35:42 2014 Sam MooreOpticsGeneralTrying to Verify the Heinert Model   06_23_14.pdf 
  87   Tue Jun 24 17:05:24 2014 Sam MooreOpticsGeneralTrying to Verify the Heinert Model It does appear that the simplified
model is only relevant for the simulations.
 To quote Heinert: "An efficient
 temperature.pngnoiseAmplitude_agreement.png 
  88   Sat Jun 28 21:59:11 2014 Sam MooreOpticsGeneralDifficulty with the COMSOL stationary module; Test Cases Here, I describe some test cases
to see if COMSOL's solutions are agreeing
with some simple analytical solutions.  Right
 6_27_14.pdf 
  89   Sun Jun 29 15:37:18 2014 Sam MooreOpticsGeneralDifficulty with the COMSOL stationary module; Test Cases

    

       
            
 6_29_14.pdf 
  90   Sun Jun 29 20:25:44 2014 KojiOpticsGeneralDifficulty with the COMSOL stationary module; Test CasesWhat about this example? The result is
easier to understand intuitively.
Consider a bar with the length of
  
  91   Sat Jul 5 13:04:32 2014 Sam MooreOptics Heinert Model TR Noise VerificationAgreement with Heinert's paper for cylindrical
TR noise has now been achieved.  Using
the stationary state assumption to calculate
 threeD_cylinderTRnoise.pngoneDcylinderTRnoise_copy.png 
  92   Mon Jul 7 19:47:00 2014 KojiOptics Heinert Model TR Noise VerificationHow close are these FEA calculations with
the analytical values? 
Can you plot residual too? (Put analytical
  
  93   Thu Jul 10 16:51:14 2014 Sam MooreOpticsGeneralDuan and Heinert Comparison(See Plots in attached document)
 
My plan has been to replicate Duan's
 7_10_14.pdf 
  94   Fri Jul 11 10:58:18 2014 not KojiOptics Heinert Model TR Noise Verification

    

       
            
 heinert_analyticalTest_residual_threeD.epsheinert_analyticTest_residual_oneD.eps 
  95   Mon Jul 14 19:09:14 2014 Sam MooreOpticsGeneralUsing Heinert's Solution for Duan's Parameters I have plotted Heinert's analytical
solution for TR noise using Duan's parameters.
 Since TO and TE noise can be found
 oneD_duanParams_residual-eps-converted-to.pdfthreeD_duanParams_residual-eps-converted-to.pdf 
  96   Mon Jul 14 19:14:31 2014 Sam MooreOpticsGeneralDuan and Heinert Comparison

    

       
            
 duan_heinert_comparisonInfinite-eps-converted-to.pdf 
  97   Thu Jul 31 20:55:38 2014 Sam MooreOpticsGeneralFinding the Right Meshing for the TIR cavity In this document, I try to identify
I good mesh by comparing the numerical solution
from that mesh with my analytical model.
 7_30_14.pdf 
  98   Sat Aug 2 00:22:34 2014 Sam MooreOpticsGeneralFinding the Right Meshing for the TIR cavity

    

       
            
 8_1_14.pdf 
  99   Tue Sep 30 11:30:27 2014 Nic, Dmass, EvanGeneralConfigurationGravity in ComsolHere
is a set of slides by Yoichi Aso on how to
handle gravity in Comsol.
  
  100   Sat Sep 5 15:04:43 2015 Dennis CoyneMechanicsConfigurationsummary of FEA modal model to State Space model At the 2014 commissioning  FEM2SS_summary.docx 
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