Define Data

Define data window allows a comfortably definition of the basic data for the analysis in most cases.

Insert the requested values in the different fields and press OK .

At least Velocity , Density , Viscosity and Length (with the corresponding units) have to be defined (if the default values are incorrect). By pressing Update , a recommended value for the Simulation Time will be calculated.

Note that you can also manually modify the boundary conditions, materials and boundaries definitions and continue the process.

The following commands are available in the Define data window:

Velocity: Speed of the free flow of the problem. The sign of this value must indicate the relative velocity of the flow respect to the body.

Simulation Time : Total time of the simulation. A recommended value of simulation time to achieve the steady state may calculated be pressing the Update button, after inserting the rest of the data.

Density : Density of the fluid.

Viscosity : Viscosity of the fluid.

Length : Body length. This value is automatically calculated and if possible, it should be left like it.

Free Surface : If a free surface is defined, you may chose between solving it iteratively, and not updating it.

OutLet type : Defines the type of boundary conditions at the outlet.

Body_type : Type of wall (boundary condition) of the body.

Turbulence model : Type of the turbulence model to be used.

Update : Updates the window data.

By pressing OK button, the following actions are automatically carried out:

  1. Material Auto_Fluid is created based on the given data. This material is assigned to the volume.
  1. Boundary Auto_Body is created with the inserted given data. This boundary is assigned to the Body_wet layer.
  1. Free surface boundary is defined (if any).
  1. Boundary conditions at the inlet, outlet and lateral boundaries are imposed.
  1. General data of the problem is defined.
  1. Units are defined.

Define data window can be accessed through the menu option Data> Problem wizards > Tdyn tools > Define data...

Note that in order to operate this tool; the geometry must be split in the standard layers, as explained in the previous step.

It is also possible to define and assign boundary conditions, materials, and boundaries manually (or modifying the assignment previously done), and then continue with the next step.

You can find detailed information on boundary conditions, materials and boundaries in the reference section of the on-line Tdyn Help (Help > Tdyn help ).

Once the data definition is completed, press Next to continue with mesh generation.