1. Data Group E: Support Vessel Data

Observe that the motion transfer function definition is related to the wave field definition. See Motion Transfer Functions in the Theory Manual for the definition of wave field and motion transfer functions. Transfer functions based on other definitions must be converted by appropriate phase shift operations before they are used as input to this program.

This data group needs not be given for systems with no vessel attachment points. Note that either Support vessel data on file or Identification through Transfer function input is to be given.

1.1. Support vessel data on file

1.1.1. Data group identifier, one line

TRANsfer FUNCtion FILE

1.1.2. File name

CHFTRA

  • CHFTRA: character(80): File name with transfer functions data

File with transfer function data given in RIFLEX format terminated with an END statement.

This group replaces the rest of group E if given. Either Support vessel data on file or Identification through Transfer function input should be given. If Support vessel data on file is given, the content on the file should be Identification to Transfer function input with an END termination.

If the vessel transfer function frequency range does not cover the entire frequency range of the analysis, the vessel response will be calculated using the transfer function in the covered frequency range and extrapolated beyond it.

For wave frequencies below the lowest frequency, the transfer function is held constant at its lowest-frequency value. For wave frequencies above the highest frequency, the transfer function is set to zero.

1.2. File format

For description of the file format, see Support vessel data - file format.