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6.1 Reference IDsSeveral of the Control File entries use reference ID numbers. It is suggested that some ranges of IDs be reserved for particular uses, for example, the 9000 entries could be reserved for load entries made using external programs (like MATLAB).

7 Software Installation on Windows7.1 Installing the SoftwareThe instructions below should be followed in order to install and test the CAEfatigue VIBRATION program in a Windows environment. For Linux installation please refer to the separate installation script.

Locate the self extracting installation image CAEfatigue VIBRATION.exe. This should have been provided to you as part of your installation package, as well as a valid license file. Place CAEfatigue VIBRATION.exe in a temporary folder (e.g. C:/temp).

Then double click to unzip and create a set of installation files.

Then double click the SETUP icon and follow installation instructions. You may be asked to install the Visual C++ Redistributable Package as below,

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If the installation of the Visual C++ Redistributable Package fails (as below) don't worry and just continue.

To continue with the installation you will need to accept the End User License Agreement.

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7.2 Testing the InstallationOnce installation has completed the following directory will be created in Program Files (x86) - if the default installation was used.

It may be difficult to use the Test_Problem_Library (TPL) directly in this location because of write protection so it is recommended that the directory be copied or moved to a user area (e.g. C:\Users\myfiles).

It might also be a good idea to copy the User Guide and Quick Reference Guide (QRG) which are in the documentation directory to a more convenient location.

Inside the TPL directory you will find a number of ready made Control Files which (along with the loading, materials and stress OP2_files subdirectories) contain everything needed to run the User Guide examples. Inside this directory put a command prompt (look in the accessories folder of the windows start programs directory for a CMD command, copy this and paste it). Then change the properties to start in %CWD% - this can then be used as an easy way to run programs from within the directory.

To run a particular Control File from within this directory (and depending on your particular installation) it should be enough to type CAEfatigue then a space followed by the first letter of the Control File name and TAB.

The line should then auto complete and pressing return should run the program.

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If the license file was not specified during installation this (demo.lic) will now be asked for. Locate and point at this file.

The program should then run through the required frequencies several times (2 times all frequencies for each subcase in the OP2 file).

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Depending on the options chosen in the Control File (see User Guide) there will be a mixture of CSV, els_fef and log files written as follows,

Results1.CSV contains the results in CSV format as follows,

if these results are sorted in excel for the worst Damage (Duty Cycle) the following results appear.

A Control File with LOGLVL=2 (note that ELSET should then be used to reduce the number of output points) will also write additional CSV files with detailed results for input PSD, transfer functions, response PSDs Rainflow cycle counts and damage results. The log file will contain information about how the job ran and summary results.

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8 User Guide ExamplesAs part of the software installation a Test_Problem_Library (TPL) is installed inside the installation directory. It is recommended that this directory is moved or copied to a user area, for example C:\Users\username\TPL. Inside this directory are 3 subdirectories with all the materials, loading and stress results files that are needed for each example. The Nastran input files (BDF and DAT) are also provided should it be required to rerun the Nastran jobs.

In order for the examples to work as provided the subdirectory structure will need to remain intact, i.e., loading, materials and OP2_files must all be below TPL. These can easily be changed using the INCDIR command.

8.1 List of User Guide Examples 1 24 (a further 17 Examples are covered in later chapters)User Guide Example 1: Basic run with LOGLEVL=0, no FEF whole modelUser Guide Example 2: Change LOGLEVL=1 elem 13897User Guide Example 3: Change LOGLEVL=2 elem 13897User Guide Example 4: Add FEF (put LOGLVEL=0) whole modelUser Guide Example 5: Change OP2 to full model (S2) whole modelUser Guide Example 6: Use TOPRMS=10% on standard OP2 (LOGLEVL=2) whole modelUser Guide Example 7: PSD + sine sweep (single DETLOAD) elem 13897/LOGLEVL=2User Guide Example 8: Sine sweep (with SINGSINE) with ZeroPSD elem 13897/LOGLEVL=2User Guide Example 9: NB sweep (with NBLOAD and NB) with ZeroPSD elem 13897/LOGLEVL=2User Guide Example 10: Multiple events with same OP2 & subcase elem 13897/LOGLEVL=2User Guide Example 11: Multiple events with same OP2 & different subcase elem 13897/LOGLEVL=2User Guide Example 12: Same as TP3 but using NB method - LOGLEVL=2 elem 13897User Guide Example 13a-f: Different types of S-N curve - LOGLEVL=2 elem 13897User Guide Example 14a-b: 2 examples that show use of FE_MAG and CNVRT1User Guide Example 15 &15a-h: Mean stress correction (15 is whole model) 15a-h different methods - LOGLEVL=2 elem 13897User Guide Example 16: MMPDS on whole model same as 15 - LOGLEVL=2 elem 13897User Guide Example 17: Check on MMPDS method with a series of sine wave analyses at different Smax and R ratioUser Guide Example 18: Static, PSD and sine sweep on whole modelUser Guide Example 19: Static, PSD and NB sweep on whole modelUser Guide Example 20: Static, PSD and simultaneous (4) detloads.User Guide Example 21: 4 simultaneous sine waves.User Guide Example 22: Random response (rms) calculation.User Guide Example 23: Random response (transfer function and response PSD) calculation.User Guide Example 24: Damage sensitivity calculation.

The Nastran model shown below was used for examples 1 to 24 in this User Guide. Note that different models are used for a further 17 examples covered later in the User Guide. The geometry, nodes and elements for this model are given in the Nastran input file model.bdf.

The necessary case control instructions to run specific jobs are then given in the following Nastran input files,

! KNrandom.dat. This file contains the case control instructions necessary to run a steady state modal analysis (Nastran SOL111) with output requested on the skin of the model (QUAD4 elements).

! KNstatic.dat. This file contains the case control instructions necessary to run a static analysis (Nastran SOL101) with output requested on the skin of the model (QUAD4 elements).

! KN_lnstatic.dat. This file contains the case control instructions necessary to run a static analysis (Nastran SOL106) with output requested on the skin of the model (QUAD4 elements).

! KNrandomS2.dat. This file contains the case control instructions necessary to run a steady state modal analysis (Nastran SOL111) with output requested on the complete model.

! KNstaticS2.dat. This file contains the case control instructions necessary to run a static analysis (Nastran SOL101) with output requested on the complete model.

! KNrandom13897_5971.dat. This file contains the case control instructions necessary to run a steady state modal analysis (Nastran SOL111) with output requested for element 13897 (QUAD4 element) and 5971 (TRIA6 element).

The model is loaded at three points as shown below. Note that time histories are shown here but in CAEfatigue VIBRATION PSDs of these load histories will be applied.

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The first 5 modes for the model are shown here and the frequency content of the loading is also shown which clearly shows that dynamic response is significant.

Figure 25. Loading applied in x, y and z direction

Figure 24. First 5 mode shapes of knuckle model

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vtabrnd 300 0.0 0.0 0.43 11.2E6 5.77 1.88E6 50 1000

endt

vmatftg 60 MPa Rangestatic 135 500 7.17E4

table 60vtabrnd 60 log log

1.0E15 121.10 2.0E11 121.10 7.19E9 150.00 1.86E7 220.001.0E6 265.50 1.71E3 400.00 5.31E1 500.00 1.0E0 645.50endt

Figure 26. PSD loading in x direction (being defined using 300_PSDload.txt)

Table 6. This is "include" 300_PSDload.txt

Figure 27. This is the S-N data represented by 60_mat1.txt

Table 7. This is "include" 60_mat1.txt

100#1.E+00# 1.E+01# 1.E+02# 1.E+03# 1.E+04# 1.E+05# 1.E+06# 1.E+07# 1.E+08# 1.E+09# 1.E+10# 1.E+11# 1.E+12# 1.E+13# 1.E+14# 1.E+15#

Stress&(M

Pa)&

Life&(N)&

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9 User Guide Example 1. Knuckle analysis with single PSD load and LOGLVL set to 0Model used: KNrandom.dat.Control File: TPL1.txtStress results file: knrandom.op2

The objective of this User Guide Example is to perform a basic random vibration response and fatigue calculation with limited output switched on (LOGLVL=0, only CSV file output no FEF file).

In order to use this Control File without change it is necessary to adhere to the appropriate directory structure with the loading, materials and stress results (OP2) files being in subdirectories of the directory in which the Control File is present.

This example uses the knuckle model stress file "knrandom.op2. The vftgload entry references the stresses from load case ID 1. Material is specified using 8 N,S points in table format (this is in an include file called 60_mat1.txt). The vftgseq entry specifies that event 100 should be applied for 1.0 seconds. EVNTOUT=1 specifies reporting for all events (in this case only one event is used). The vftgevnt entry shows that the event contains only one load with reference 401. This reference points at a vrandps entry

where we see J=K and X=1, Y=0 which means it is a single direct PSD (no cross terms). Then the vrandps entry includes a reference to a linear - linear PSD table (this is in an include file called 500_PSDload.txt). A CSV file output is requested. Minimal (LOGLVL=0) output is requested for the whole model. Signed von-Mises equivalent stress is specified. A request to write a detailed copy of the S-N material is made using "matout" on the vftgparm entry. An output file name of Results1 is specified and so results will therefore be written to the Results1.csv and Results1.log files.

In order to run this User Guide Example open a command prompt (one is provided in the TPL) and type

caefatigue TPL1.txt

This should take a few seconds to run and the following files should be produced

Results1.logResults1.csvResults1_vmatftg_60.txt

Because LOGLVL was set to 0 only minimal runtime information is written to the log file (see below). The main results are written to the CSV file as below.

vibfat 777 csv nastran Corner 0 Results1vftgdef 777 Dirlik 100 60 16 99.9 16 64include materials/60_mat1.txtvftgparm777 sn

stress sgvon none matoutvftgseq 777 1 seconds 1.0

100 1.0vftgevnt100 401vftgload401 PSD 500 1.0 1 "OP2_files/knrandom.op2"

vrandps 500 1 1 1.0 0.0 300include loading/300_PSDload.txt

Table 8. Control File for User Guide Example 1

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9.1 CSV (Comma Separated File)

The CSV file contains all the output results in condensed format as follows

Column Results Type7 0th moment A description of how spectral moments are calculated8 1st moment is given as part of User Guide Example 2. 4 moments are9 2nd moment calculated m0, m1, m2 and m4 and all 4 are reported.10 4th moment11 Root Mean Square (stress) The intensity of the process given by sqrt(m0)12 Root Mean Square (strain) The intensity of the process in terms of strain13 E[0] Zero crossings or number of mean crossings per second14 E[P] Number of peaks per second15 Irregularity factor Zeros divided by peaks per second16 Mean Stress Mean stress (in COMB units) obtained from SOL101/106 OP2 file17 Mean + P*sigma (stress) This is P (Maxpeak) times the rms added to the mean18 Mean P*sigma (stress) This is P (Maxpeak) times the rms taken from the mean19 Mean + P*sigma (strain) This is the strain corresponding to the stress in column 1720 Mean P*sigma (strain) This is the strain corresponding to the stress in column 1721 Damage per second Palmgren Miner Damage sum22 Log of Damage per second Log of the damage sum23 Life in seconds 1/damage per second per second24 Life in cycles Life in seconds times E[P]25 Margin of safety

Blue columns are as per release 1.0 but with change to heading. Red columns are new in release 2.0. All other columns as per release 1.0.

To make it easier to read these columns they have been enlarged below.

An individual result is written for each grid ID in the model. There will be an individual grid ID for each element, grid (node), layer and event.

A B C D E F G H I J K L M N O P Q R S T U V W X Y

Element Grid Layer ELSETID MID Event m0 m1 m2 m2 rms_stress rms_strain E[0] E[p] Irr_FactorMean Stress

Mean +3sigma_stress

Mean-3sigma_stress

Mean+3sigma_strain

Mean-3sigma_strain

Damage (Duty Cycle)

Log Damage (Duty Cycle)

Life(seconds)

Log of Life(seconds) MOS

A B C D E F G H I J K L M N O P

Element Grid Layer ELSETID MID Event m0 m1 m2 m2 rms_stress rms_strain E[0] E[p] Irr_FactorMean Stress

Q R S T U V W X Y

StressMean

+3sigma_stressMean-

3sigma_stressMean+3sigma_

strainMean-

3sigma_strainDamage (Duty

Cycle)Log Damage (Duty Cycle)

Life(seconds)

Log of Life(seconds) MOS

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The User Guide Example 1 results have been sorted in excel (using Data Sort based on damage) and then shown below.

Table 9. Output CSV file after sorting with excel

The most highly damaged grid ID is for element 12994 and grid (node) 2622 (damage of 1.01E-03). Note that the most highly damaged element center (grid ID 0) is for element 13897 with a damage of 2.88E-07. There is only one event (100) included in this analysis.

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9.2 LOG (Detailed ASCI Text File).

The LOG file contains different quantities of information, depending on the LOGLVL value, which is specified. If LOGLVL=0 then basic runtime information is produced as follows,

Table 10. LOG file that is written with LOGLVL=0