March 11, 2020
Free surface is the surface of a fluid that is subject to zero parallel shear stress, such as the interface between two homogeneous fluids, for example, liquid water and the air in the Earth’s atmosphere. Unlike liquids, gases cannot form a free surface on their own. Fluidized/liquified solids, including slurries, granular materials, and powders may form a free surface.
A liquid in a gravitational field will form a free surface if unconfined from above. Under mechanical equilibrium this free surface must be perpendicular to the forces acting on the liquid; if not there would be a force along the surface, and the liquid would flow in that direction. Thus, on the surface of the Earth, all free surfaces of liquids are horizontal unless disturbed (except near solids dipping into them, where surface tension distorts the surface in a region called the meniscus).
In a free liquid that is not affected by outside forces such as a gravitational field, internal attractive forces only play a role (e.g. Van der Waals forces, hydrogen bonds). Its free surface will assume the shape with the least surface area for its volume: a perfect sphere. Such behaviour can be expressed in terms of surface tension. It can be demonstrated experimentally by observing a large globule of oil placed below the surface of a mixture of water and alcohol having the same density so the oil has neutral buoyancy.
In this tutorial you will learn to simulate a free surface in 2D using ANSYS CFX. First, we will build a geometry and then we will generate the mesh using a structured mesh in Ansys Meshing.
The NACA four-digit wing sections define the profile by:
First digit describing maximum camber as percentage of the chord.
Second digit describing the distance of maximum camber from the airfoil leading edge in tenths of the chord.
OpenFOAM is the free, open source CFD software developed primarily by OpenCFD Ltd since 2004. It has a large user base across most areas of engineering and science, from both commercial and academic organisations.
In this tutorial, you will learn how to simulate a porous media using Ansys Fluent. In the first part, you can create the geometry and the mesh and the second part Ansys Fluent setup.
In this tutorial, you will learn how to configure your simulation with the Convection and analyze the convergence criteria to obtain accurate results
In this tutorial, you will learn how to simulate an Elbow 3d using Ansys Fluent, This is a basic tutorial and you can use Ansys Student version.
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