Help with DualSPHysics

islem

Hello,

I am working on Fluid Structure Interaction problem in which I am supposed to calculate the deflection of a wall that surrounds a storage tank after the stored fluid escapes the tank and hits the wall. I heard that SPH is a monolithic approach that solves FSI problem. After I read the users guide and examined the tutorials and run some of them I couldn't find the deflection of the structure in the result, e.g in the case of dambreak, there is no deflection of the obstacle as well the material of the structure is not defined which is crucial in FSI simulation.
I want to know using this software, can I get the deflection of the wall under the impact of the fluid ?

I want to check as well the procedure to run my own case. Is all what I need to do is to modify the case_def file and keep case.bat file shipped with the tutorials unmodified or the latter needs to be modified, if so how to do it ?

Finally, I want to know what are the output of SPH simulation? Can I get the velocity,the pressure and the delection?

Something weird happens, I run a simulation 4 hours ago, I got vtk files for each part_xxxx and then I visualized the results with paraview and then I wanted to see the results again but I couldn't find the output files, that happens with the damBreakcase DualSPHysics v_3.2 and casePeriodicity_out for the version4. Both of the versions run on windows.

Regards,
islem

Alex

Deflection of the wall is deformation or movement of the rigid object?
The first one is not simulated with DualSPHysics, the second it is as shown in CaseSolids in CASEDEM.

To create your cases, you should also read the XML:v4.0_GUIDE.pdf.

islem

Hi,

Thank you Alex for your reply.
I mean by deflection the degree to which a structural element is displaced under a load. It may refer to an angle or a distance.
Is the stress with which the body respond to the impact of fluid simulated ?

Regards,
Islem

MikeHersee

As a follow-up question to islem's query, I'm also planning to make use of the flexibility of floating objects in order to achieve certain effects, that I presumed was simulated as the Young's modulus is a property in the materials file - in fact, due to an error, at one point a simulation wouldn't run because the young's modulus was not set. But Alex's comments makes me wonder if the degree of stiffness is simulated at all. Do floating objects not have a stiffness that depends on the material properties?

Alex

You can use the cases where SPH is coupled with DEM but only rigid contacts are simulated. Young modulus and friction coefficient can be simulated for different materiales but there is no deformation of the object, only some elastic interaction. You can check it running cases in CASEDEM folder and you can also read the paper of reference about DEM:

Canelas RB, Crespo AJC, Domínguez JM, Ferreira RML and Gómez-Gesteira. 2016. SPH-DCDEM model for arbitrary geometries in free surface solid-fluid flows. Computer Physics Communications. doi:10.1016/j.cpc.2016.01.006.

Regards