F-DEMPack Tutorial 2: Annular pipe
Before starting with this tutorial, the user is strongly encouraged to follow the D-DEMPack Tutorial 2: Conveyor belt to get a feeling of how the problem type works, and in particular the DEM section. This tutorial will focus mainly in the Fluid section and its particularities.
The process should start by creating a new geometry from scratch, by modifying an existing one or by opening a finished one. It is assumed that the user already knows how to do this procedure so no details will be given about it.
In this tutorial, a simple geometry was created for the sake of simplicity. The idea is to understand all the steps involved in the problem type. The user must start by downloading the file File:F DEMPack2 Tutorial 6.gid.zip, which contains the geometry and mesh of the proposed geometry. This file has already created the groups that will be used in the simulation.
The geometry of study consists of an annular tube through which a flux of an intermediate viscosity mud passes. An inlet creating DEM particles with time is located in the base of the annular pipe.
The downloaded file has already created the groups that will be used in the simulation.
In this sample case, the following five groups were created: Dem_inlet, Fluid, Inlet, No_slip and Outlet. The lower circle (surface) would be the Inlet, the smaller one just on top of it was the DEM_Inlet, the circle at the top would represent the Outlet, the No_slip would be the walls of the cylinder and, finally, the volume named Fluid would constitute the mass of fluid.
We will continue by defining the properties of the fluid in the simulation. We just have to click on the icon showing in the next figure to open the menus and in particular the Materials tab:
To begin inserting the fluid properties, we click on Fluid and then on the plus button at the bottom of the window to add a new Fluid material.
The next figure shows the details of the fluid material parameters that have been used in this example. To fill in or modify the value of the parameters, just unfold the General and Fluid submenus and double-click on the corresponding current data. The following data corresponds to an intermediate viscosity mud.
The same process can be followed, in this case, for the DEM material. We unfold the DEM-Defaultmaterial submenu at the bottom of the same window and fill the fields with the appropriate data. See Figure 6.
General Application Data
We now need to tell the program the model characteristics: boundary and initial conditions, inlet options, time considerations, etc. To begin filling all this data, we just click on the Model menu located at the left of the Materials tab and the Model Properties window will show up. This menu can be accessed also by clicking on the icon showing in the next figure:
The first section of the menu is General Application Data. Within this section the user can specify some simulation parameters and coupling parameters between both subdomains.