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Ansys Learning Forum › Forums › Discuss Simulation › Fluids › Errors with multi-connected bodies using AQWA › Reply To: Errors with multi-connected bodies using AQWA

April 17, 2024 at 1:29 pm
S.S.S.ShankaVasuki
Subscriber

Hi,

Thank you for your response. Just to give you more context on the problem I am trying to solve. Basically I want to estimate the hydrodynamic response of a flexible floating structure. Hence this flexible structure is broken into multiple rigid blocks connected together with hinges. Ideally there would be around 8-10 blocks connected together in total. But to just get a hang of solving this problem, I am just using two blocks as a starting point.

I have tried two things:

  1. Original Case: This is the problem that I have initally mentioned in my post.  The image below shows my model setup and the locations of the connection points I have used. Here all the surfaces are diffracting and the error I get is this - " HYDRODYNAMICALLY INTERACTING STRUCTURES HAVE MOVED TOO FAR FROM ANALYSIS POSITION MOVEMENT EXCEEDS 75% STOPPED AT TIME = 0.00."

 

2. Updated case: This is the latest simulation I ran incorporating your suggestions of having the 2 hinge connection points (T1,T2) at the middle of the gap. With this I ran two simulations, one where all the surfaces are diffracting and second with only the surfaces in contact with the water as diffracting. You can get a better idea of this setup with the image below. In both simulations the old error goes away and there is a new error which says - " SOLVEG:PRINCIPAL MINORS ARE NOT NON-ZERO,TRIANGULISATION ABANDONED - LINE13."

 

Please let me know on how to solve this problem. I have actually spent a lot of time figuring this out without any success. Any help would be great! :)

Thanks!