current forces coefficients and wind force coefficient in AQWA

Hi Everyone

I'm a freshman in AQWA. These day I am working on a project name Spar-type floating offshore wind turbines. I am interested in the dynamic behaviors in multiple-DOFs (Surge,Heave and Pitch). The Spar are 8 meters in diameter and the total draft is 65 meters.The upper structure, including tower and nacelle and turbine, remains the same as the fixed-bottom ones. I am required to take all of the environmental loads (current, wind and wave) into account. We noticed that AQWA-Drift may be a proper solution for us. But in the input file of AQWA-Drift, Deck 10 requires information of current forces coefficients and wind force coefficient. How to calculate these coefficients ?

Is there someone who can help me ?

Thanks!

 

Usually, these coefficients depend on the shape/slenderness of your elements and the flow velocity regime. You can start considering one for all of them and should be fine for starting.

A question for you: have you used Morison TUBE elements? If that is the case, would it be possible to have their entries in analysis.dat file? we are having problem defining them from the workbench

 

Wang Yangming,

Read the AQWA help carefully, the drag coefficients are not required. I would suggest omitting them entirely, at least for now.