Gravity and Boundary Conditions
Application ID: 2152
The influence of gravity on the flow pattern is often an important issue when modeling flow in fluids with variable density. You can account for this influence in the model equations by adding, to the momentum balances, the volume force.
This model shows a simple example of the implementation of boundary conditions when volumetric forces are included in the momentum balances. This can be used to account for hydrostatic pressure and to account for density variations in free convection problems.

This model example illustrates applications of this type that would nominally be built using the following products:
however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
The combination of COMSOL® products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries. Particular functionality may be common to several products. To determine the right combination of products for your modeling needs, review the Specification Chart and make use of a free evaluation license. The COMSOL Sales and Support teams are available for answering any questions you may have regarding this.