Learning Forum

[lakshmik94]

I need to solve for finding free decay in heave of a free floating cylindrical strcuture. can someone help me in detailing the steps. 
I am relatively new to AQWA 

[Mike Pettit]

 

Hello,

As an Ansys employee I can only give a limited amount of support in the Learning Forum, but the general steps you need to follow are:

 

• Create the cylinder geometry in DesignModeler/SpaceClaim/Discovery, if you do not already have a geometry file;
• Create the following workflow on the Workbench Project Schematic, using the cylinder geometry to define the Geometry cell:

 

 

• Open the Aqwa Workbench editor, and define a Point Mass for the cylinder, plus a Connection Point (the location of this is not important);
• Generate the Mesh, then set up and solve the Hydrodynamic Diffraction analysis;
• Change the Computation Type in the Hydrodynamic Response Analysis Settings from 'Stability Analysis' to 'Time Response Analysis';
• Add a Starting Position to the Hydrodynamic Response analysis, with the Connection Point as the Reference Point, and set the Position Z to define the initial position of the cylinder;
• Set up the other Hydrodynamic Response Analysis Settings as necessary (Duration will need to be increased), add a Structure Position result for the cylinder Global Z position, and Solve.

 

You may consider adding a Morison Disc to the cylinder so that the viscous drag forces are also modelled.

I hope this helps!

Mike