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.
In this tutorial, you will learn how to simulate a Heatsink using Ansys Fluent. In this first video, you will see how to create the geometry and the mesh using DesignModeler, Ansys Meshing and Ansys Fluent.
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...
In this tutorial, you will learn how to simulate a blower (unsteady) using Mesh Motion with Ansys Fluent. Please download the mesh.
Stay Up to Date With The Latest News & Updates
Help us keep growing
CFD.NINJA is financed with its own resources, if you want to support us we will be grateful.
Join Our Newsletter
Subscribe to receive emails with detailed information related to the CFD.
Subscribe to our social networks to receive notifications about our new tutorials