vddam

Mapdl.vddam(vf='', va='', vb='', vc='', **kwargs)

Specifies the velocity spectrum computation constants for the analysis

APDL Command: VDDAM of shock resistance of shipboard structures.

Parameters
  • vf – Direction-dependent velocity coefficient for elastic or elastic- plastic analysis option (Default = 0).

  • va – Coefficients for the DDAM velocity spectrum equations. See Dynamic Design Analysis Method in the Mechanical APDL Theory Reference. Default for these coefficients is zero.

  • vb – Coefficients for the DDAM velocity spectrum equations. See Dynamic Design Analysis Method in the Mechanical APDL Theory Reference. Default for these coefficients is zero.

  • vc – Coefficients for the DDAM velocity spectrum equations. See Dynamic Design Analysis Method in the Mechanical APDL Theory Reference. Default for these coefficients is zero.

Notes

This command specifies velocity coefficients to analyze shock resistance of shipboard equipment. These coefficients are used to compute mode coefficients according to the equations given in Dynamic Design Analysis Method in the Mechanical APDL Theory Reference. The form of these equations is based on the Naval NRL Dynamic Design Analysis Method. This command, along with the ADDAM and SED commands, is used with the spectrum (ANTYPE,SPECTR) analysis as a special purpose alternative to the SV, FREQ, and SVTYP commands. The mass and length units of the model must be in pounds and inches, respectively.

DDASPEC may alternatively be used to calculate spectrum coefficients.

This command is also valid in PREP7.