Below is an example loading for Single Frequency analysis in the embedded add-on.

This is the equivalent DesignLife Integrated Vibration Generator configuration. In the Advanced tab, define the Type as SineDwell.

The table defined is as below.

The main difference in the two approaches is the Exposure Duration property, which is not explicitly defined in the Integrated workflow. The general rule is to multiply the Frequency and Exposure Duration from the add-on load provider and use the product as input to the Number of Cycles field in the Vibration Generator Glyph.

Go to the Vibration Load in the Analysis Glyph and ensure that the LoadingConfigSource field is set to MetaData.

Below is an example of Frequency Range loading in a vibration fatigue analysis in the embedded add-on.

This is the equivalent DesignLife Integrated Vibration Generator configuration. In the Advanced tab, define the Type as SineSweep2.

In the Vibration Generator Configuration, additional inputs are required to the StartFrequency and EndFrequency fields. This would correspond to the frequency range defined in the upstream Harmonic analysis. The AdditionalNumberOfSweeps field is not equivalent to the Number of Sweeps field in the embedded add-on load. The equivalence depends on SweepType used (see the sections below for more information).

Go to the Load Provider option in the Analysis Glyph and set LoadConfigSource to Metadata.

The excitation applied in the steady state dynamics FE analysis as a frequency sweep with ‘unit’ magnitude

must match both model units and the input PSD units.

PSD and Swept Sine Inputs

Advanced tab

All properties on this form are passed out as metadata (as described in the image above):

General

Histogram Output

Sinesweep2

Vibration Properties tab

Data in the Vibration Properties tab is set manually and the data in this table is passed out as metadata as a packet named VibrationTables.

This table is defined on the Advanced tab by:

SineSweep2 Metadata Example:

<Set name="VibrationGenerator1_Properties">
<Item name="AdditionalNumberOfSweeps" type="Long" value="0"/>
<Item name="EndFrequency" type="Float" value="1000"/>
<Item name="FrequencyStep" type="Float" value="1"/>
<Item name="InterpolationMethod" type="String" value="Log"/>
<Item name="StartFrequency" type="Float" value="1"/>
<Item name="SweepRate" type="Float" value="1"/>
<Item name="SweepType" type="String" value="OctavesPerMinute"/>
<Item name="TestDuration" type="Float" value="600"/>
<Item name="TestType" type="String" value="Acceleration (g)"/>
<Item name="Type" type="String" value="SineSweep2"/>
<Item name="VibrationTable" type="String" value="PropertiesTab"/>
<Item name="XMLTables" type="String" value=“VibrationGenerator1_Properties"/>

<VibrationTables Version=""1.0"">
 <Tables>
  <SineSweep2>
   <SineSweep2Item Amplitude=""0.1"" Frequency=""1""/>
   <SineSweep2Item Amplitude=""5"" Frequency=""10""/>
   <SineSweep2Item Amplitude=""20"" Frequency=""100""/>
   <SineSweep2Item Amplitude=""10"" Frequency=""1000""/>
  </SineSweep2>
 </Tables>
</VibrationTables>

SineSweep2 Acceleration Histogram

The histogram output is controlled by the following Advanced tab properties:

The amplitudes for the histogram are obtained from the table on the Vibration Properties tab.

The FRF can be paired up with metadata from Vibration Generator (see below).

When LoadingConfigSource is set to Metadata (see below), the swept sine definition in DesignLife is calculated from the Vibration Generator metadata properties.

The histogram from the Vibration Generator is not used, the sweep range is defined by the XMLTable in the metadata.

When LoadingConfigSource is set to Custom, the swept sine definition in DesignLife is calculated from the Vibration Generator histogram and properties set on the Advanced tab.

When the LoadingConfigSource is switched from Custom to Metadata and then back to Custom, load provider properties are set to those calculated from the Vibration Generator settings.

If the frequency ranges defined on the Advanced tab and Vibration Properties tab of the Vibration Generator were not the same, a Custom run and a Metadata run will generate different results.

Swept Sine Sweep Rate Calculations

where,

Time = total duration of test

f_min = starting frequency of sweep in Hz

f_max = ending frequency of sweep in Hz

Sweep_Rate = sweep rate in sweep rate type

SineDwell properties are set for:

These are passed out as metadata, with no histogram data output.

Advanced Tab

LoadingConfigSource must be set to Metadata.

The analysis uses amplitude, frequency and number of cycles from the Vibration Generator metadata.

The DesignLife load provider must be set to the appropriate amplitude, SineDwellFrequency and SineDwellDurationSeconds.

Edit Loading Tab

The FRF (Frequency Response Function) is paired up with acceleration data. Load data can be multicolumn or histogram curves of acceleration amplitude versus frequency. The dwell frequency must be inside the range of the sine sweep contained in the load data.

Advanced Tab

SineDwell Properties

The duration is the summation of:

When LoadConfigSource is set to Custom, the dwell amplitude is determined from the sine sweep loading selected on the Edit Loading tab.

SineDwellDurationSeconds = (Number of Cycles)/(Frequency (Hz))

where Number of Cycles & and Frequency are set in the Vibration Generator.

PSD (Power Spectral Density) is defined in Vibration Properties.

SineFrequencies and SineAmplitudes are output as metadata.

Advanced Tab

PSD is input from metadata containing 4 frequency steps.

Amplitudes and frequencies of sine tones are input as metadata.

ExposureDuration and CycleCountingMethod are DesignLife properties.

The default frequency selection method is used if:

Frequency Steps used in Solution

In the example below, the default frequency selection method was initially used, but the PSD frequency steps from metadata and the FRF frequency steps from the harmonic solution did not have enough resolution to define the stresses.

Switching the FrequencySelectionMethod to UserDefined, and specifying a 1 Hz frequency step corrected the issue (see below).

Advanced Tab

The lack of resolution in the frequency steps (above) was not immediately obvious.

Use of a modal FRF with fine frequency spacing is recommended.

Though the loading input is still from the Vibration Generator, with the Custom setting selected the only input is the PSD as a histogram.

This makes the default frequency selection method an adequate choice.

As before, the ExposureDuration and CycleCountingMethod are both DesignLife properties.

Below is the table conversion to see the DesignLife properties when setting the Vibration Generator.

where,

Time = total duration of test

f_min = starting frequency of sweep in Hz

f_max = ending frequency of sweep in Hz

Sweep_Rate = sweep rate in sweep rate type

See examples of conversions below: