13.5. The LFAD Data Record - Use Lowest Wave Frequency Added Mass and Damping for Drift Frequency Analysis

The default low frequency added mass is the added mass calculated in Aqwa-Line at the lowest wave frequency.

The default low frequency damping is zero.

      2   5  7    11
    - --- -- ---- 
   |X|   |  |LFAD|
    - --- -- ---- 
       |  |   |   
       |  |   |   
       |  |   |   
       |  |   |   
       |  |   |
       |  |   |_Optional Data Record Keyword(A4)
       |  |
       |  |_Optional User Identifier(A2)
       |
       |_Compulsory END on last data record in data categoy(A3)

Note:

When this data record is on, the DGAM and DGDP data records should be omitted, and the program will use the added mass and damping calculated in Aqwa-Line at lowest wave frequency for drift frequency analysis.
When the convolution method is used, i.e. CONV option is on, in a time domain analysis, Aqwa automatically calculates the low frequency (asymptotic) added mass and this data record is ignored. Any additional added mass or damping should be frequency-independent, specified using the FIDA, FIDD, FIAM or FIDP data records (The FIDA/FIDD Data Record - Frequency Independent Diagonal Added Mass/Damping and The FIAM/FIDP Data Record - Frequency Independent Added Mass/Damping Matrices).