## Chapter 12: Domains

This chapter describes:

- Creating New Domains
- The Details View for Domain Objects
- Using Multiple Domains
- User Interface

CFX-Pre uses the concept of domains to define the type, properties, and region of the fluid, porous, or solid. Domains are regions of space in which the equations of fluid flow or heat transfer are solved. This section describes how to use the domain details view to define the physics of fluid, porous or solid domains in your simulation. This includes selecting the 3D bounding regions and choosing appropriate physical models.

A list of the physical models available in CFX, as well as additional information on the physical meaning of the models used, is available. For details, see Physical Models in the CFX-Solver Modeling Guide.

Domains are created from a list of Assemblies, 3D primitive regions and/or 3D composite regions that are associated with a volume of an imported mesh. A discussion of these objects can be found in CFX-Pre. For details, see Mesh Topology in CFX-Pre.

In some cases, separate domains will need to be connected via a domain interface, while in other cases, no interface is required or a default interface is created and is suitable. For details, see Domain Interfaces.

Within fluid, porous, and solid domains, internal 3D regions can be assigned to a subdomain. These are used to create volumetric sources of mass, momentum, energy, and so on. For details, see Subdomains.

Boundary conditions can be applied to any bounding surface of a 3D primitive that is included in a domain (that is, including internal surfaces). For details, see Boundary Conditions.

Release 18.2 - © ANSYS, Inc. All rights reserved.