How to simulate zigzag maneuver using current KCS setup

[jerinm240814ce-cell]

I’d like to perform a zigzag maneuver (e.g. 10°/10° or 20°/20°) using the same case.

Could you please let me know how to set up the zigzag steering input in this code?
For example, should I modify the rudder control file, or is there already a way to apply a time-dependent rudder angle in the current setup?

[balabibo]

Hi,
For a 20/20 zigzag, you could add a sub dictionary in dynamicMeshDict as follows:

maneuvers
{
            control2
            {
                type          zigzag;
                refBody       hull;
                actBody       rudder;
                controllerYawAngle  20;
                controllerRudder  20;
                controllerRate    35;
                controllerStartTime    0;
                controllerEndTime   1000;
            } 
}

[jerinm240814ce-cell]

Thank you for the guidance on setting up the 20/20 zigzag.

I have a follow-up question regarding changing the Froude number by modifying the hull velocity. When I try to adjust the velocity to achieve a different Froude number, the simulation runs initially but stops soon after the turning maneuver begins.
I’m also facing a similar issue when changing the trim conditions of the hull. The case terminates prematurely once the motion starts.
Could you please advise what might be causing this or how to handle these cases properly?

[balabibo]

Hi,
I'm sorry but I want to know more details to answer your question. How did you modify the hull velocity? Generally, we use sailingcontroller and set controllerTarget to target speed of hull, the simulation will justify the rotation speed of propeller, and push the ship to reach the target speed. When you notice the ship velocity reach the target, you should set the propeller rps to a constant value, that means set controllerMax controllerMin to a constant value. I should emphasis that, if you terminate the simulation and try to restart, you should modify the file in timeName/uniform/maneuvers (like 10.0/uniform/maneuvers). Because the simulation will read the maneuvering control from this dictionary rather than dynamicMeshDict at the beginning. Hope it helps!