Problem Description

The first simple verification problem selected for the ElmerFoamFSI suite is a static case of a viscous fluid applying uniform pressure to a cantilever beam. The fluid domain is square with uniform pressure, there exists no fluid velocity, and no motion occurs on the side and top walls. The bottom wall consists of a solid cantilever beam, attached on one side but free to move in the y-direction elsewhere. Since there is no fluid velocity the only contributing factor affecting the beam’s displacement is due to the pressure from the fluid with no traction. Therefore, this first problem verifies the pressure component of the total force being applied to the beam, ensuring that this piece of the coupling of the fluid and solid applications is correct. Figure 1 shows the geometry of the problem.

Figure 1. Domain and boundary conditions for simple static verification problem

The dimensions of the domain are $ L = 1.0 m $ , $ h_s = 0.1 m $ , and $ h_f = 1.0 m $ . The velocity profile is initialized to $ 0.0 m/s $ and the pressure is given a uniform value of $ 1.0 Pa $ .
The out-of-plane dimension is selected to be 0.1 m for both domains, arbitrarily. The table below summarizes the properties of the solid and fluid used in the simulation.

Table 1. Properties of fluid and solid domains.

Running The Simple Static Problem

The instructions here utilize Simple Dynamic Problem as a starting point in terms of the input files and their functions. To execute the simple static verification problem with ElmerFoamFSI, Elmer input and ElmerFoamFSI input file should be copied to the ./fluid folder of the OpenFOAM input hierachy. Following directions are steps to take to run a problem :

Obtain input_data files for SimpleStatic problem
Create a folder and copy the following two scripts: Allclean, Allrun; ./fluid/ and ./solid/ folders into this new folder, making sure to copy all sub-folders as well

Make sure your folder has following files: Allclean, Allrun, AllrunPar, makeLinks, makeSerialLinks, removeSerialLinks (scripts so far), fluid(folder), solid(folder)
Copy Elmer SIF, GRD and ELMERSOLVER_STARTINFO files to /fluid/
Run ./Allclean and ./Allrun to clean-up and prepare input files for the OpenFOAM
Go to ./fluid/ and type "ElmerGrid 1 2 name", where "name" should be replaced with the name of the GRD file for Elmer
Run ElmerFoamFSI, the FSI simulation by "elmerformfsi name", where "name" should be re-placed with the name of ElmerFoamFSI input file

./path/to/elmerfoamfsi/elmerfoamfsi test.config

As a result of simulation, you will obtain VTK,VTU outputs along with many log files. Output files can be further post processed by using tools such as Paraview.