Dear Yu.Lei,
Based on your various questions, presumably you are deriving the tower mode shapes for a wind turbine atop a floating platform. In this case, you can set the distributed (hydrodynamic) added-mass and distributed elastic sitffness per unit length along a flexible portion of the tower length to zero because all of the hydrodynamic loads are applied to the platform rather than the tower.
Regarding the use of ModeShapePolyFitting.xlsx, you must identify the tower modes from the BModes output file. You can then copy the “span_loc” into the “x” column of the spreadsheet and either the “s-s disp” or “f-a disp” into the “y” column for the side-to-side and fore-aft modes, respectively. For the “Improved Direct Method” and “Projection Method”, you can get the “slope (i.e. dy/dx) at bottom” from the “s-s slope” or “f-a slope” outputs from BModes.
Regarding the hydro_K and hydro_M matrices derived from WAMIT output, the WAMIT is nondimensional whereas hydro_K and hydro_M must be dimensionalized. See my post dated Jul 01, 2011 in the following forum post for more information: WAMIT - #4 by Jason.Jonkman.
I hope that helps.
Best regards,