Seite - 1454 - in Book of Full Papers - Symposium Hydro Engineering

6. FLOW-3D 6.1. INTRODUCTION Flow-3D is software for fluid dynamics in various systems. The user interprets the behaviour of fluids with using numerical methods, the model itself, boundaries and initial conditions, the user interprets the behaviour of fluids. Overall, the survey is performed using the Volume of Fluid mathematical method. A great advantage is the software’s resilience to geometrically complicated and un-repaired models. While other software products require precisely repaired and imported models, Flow-3D also works with very difficult 3D objects without any errors. The software itself includes, among other things, an internal function that corrects the remaining inaccuracies. Its name is Qadmesh. There is lot of tools inside this function, but there is also a risk that the repairing process will change the original model. It will actually fix the imperfections but at the cost of losing real parameters. 6.2. PROCEDURE After launching the software and looking into the work environment, user can see organized cards. Main cards that have a sub-card group you must expand one after the other and set up the entire process. Overall, the core part is based on detailed modification of the mesh network. It is simple to create, manipulate and also to import your own shape. Before simulation, it is necessary to know the fact that the smaller cells in the mesh (the smoother the process will be created), the more complicated and longer calculation becomes. Another advantage of the grid is the ability to modify it so that the network is denser at the point where it is needed. • New Simulation - at the beginning user have to choose the type of simulation or physical process (flow over weir), • Physics - another step is to define appropriate condition (gravity, viscous, turbulence etc.), • Meshing and geometry - creating a simple geometry object (or import the complicated) and then create a mesh network, • Output and numeric - in this step user chooses, what he wants to calculate inside the mesh (velocity, pressure, fraction fluid and others), 1454