Forces acting on floating body

DuncLambDuncLamb
in DualSPHysics v5.0

I recently ran two very similar DualSPHysics simulations. Both included a floating body excited by regular waves, the difference being one was connected to the bottom of the tank by a chrono spring. My questions arose while analyzing the plots of "ForceTotal.z", generated by compute forces, for both simulations. I will attach the plot of the forces for each simulation followed by my questions.

Forces.png

1. The chrono spring clearly has an effect of the forces acting on the body, however, I cant figure out a way to singularly analyze the chrono spring force. The "ChronoLink_forces.csv" generated is filled with zeros, I also noticed this to be the case for the examples using chrono springs. I read a previous comment by @Alex (will attach below) explaining the different chrono output files, but I seem to still have a misunderstanding. Is there a way to view the reaction force from the spring?

2. the output from compute forces seems to be very choppy/noisy. Is this inherent to the compute forces function and is there a way to avoid it? I assume this is more a measurement error or else it would be reflected in the displacement curves.

Any help would be greatly appreciated. Thank you in advance! 😃

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Alex

To get output info related with this you have to use:  

<savedata value="#TimeOut" comment="Saves CSV with data exchange for each time interval (0=all steps)" />

- ChronoExchange_mkbound_XX. Information exchanged between Chrono and DPSH. You have to use:

InputFace [X,Y,Z]: Linear acceleration applied from DSPH to the object in Chrono. (DSPH ---> Chrono)

InputFomegaAce [X,Y,Z]: Angular acceleration applied from DSPH to the object in Chrono.  (DSPH ---> Chrono)

Both ChronoBody_forces and ChronoLink_forces are the forces applied by Chrono to each object at each time step (FLUID + F. EXTERNAL + COLLISIONS).

- ChronoBody_forces: Includes the accumulated forces applied to the object in Chrono 

AcumulatedForce [X,Y,Z]: Linear forces

AcumulatedTorque [X,Y,Z]: Angular forces or torques

-ChronoLink_forces: Reaction forces of the links(Links: LinkSpring, LinkPulley....).

 ReactForce [X,Y,Z]: Linear forces of reaction

 ReactTorqe [X,Y,Z]: Angular forces or torsional


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