POWERFLOW

I/O Options EntryUsed to request output of the power flow field.

Format

POWERFLOW (format,peakoutput) = option

Definitions

Argument Options Description
format <H3D>
H3D (Default)
Results are output in Hyper3D format (.h3d file).
peakoutput <PEAKOUT>

Default = blank

If PEAKOUT is present, only the filtered frequencies from the PEAKOUT card will be considered for this output.
option <YES, ALL, NO, NONE, SID>

Default = ALL

YES, ALL, blank
Power flow field is output for all elements.
NO, NONE
Power flow field is not output.
SID
If a set ID is given, power flow field is output only for the contents of that set.

Comments

  1. Power flow field output is only available to the .h3d file. It is currently supported for:
    • Direct and modal frequency response analysis.
    • Direct and modal transient response analysis.
  2. The power flow field indicates the magnitude and direction of vibrational energy which travels in dynamically loaded structures. It helps with identifying the energy transmission paths as well as the vibration sources and energy sinks. Structural intensity, defined as the power flow per unit area, is also available.
  3. The Power flow field and mechanical intensity output are available for solid element sections defined with the SECTION Bulk Data Entry (with STYPE=FLOW). The contribution of all elements in the cross-section is calculated along the direction normal to the surface. These contributions are added together to calculate the power flow at the cross-section. The mechanical intensity is equal to the power flow divided by the area of the cross-section. The results are output only in the .h3d file. All grids in a give cross-section are assigned the same value.
  4. The references used in the calculation of the power flow field are listed in the References section of the User Guide.