Home
User Guide
View detailed information regarding the features, functionality, and simulation methods available in ultraFluidX.
Simulation Parameters
Available parameters for defining simulations in ultraFluidX.

Welcome
What's New
View new features for ultraFluidX 2024.1.
Get Started
Learn the basics and discover the workspace.
User Guide
View detailed information regarding the features, functionality, and simulation methods available in ultraFluidX.
- Simulation Parameters
  Available parameters for defining simulations in ultraFluidX.
  - <simulation>
    The <simulation> category specifies the main parameters of the simulation like the number of iterations, and the file containing the surface mesh or the fluid material.
  - <geometry>
    The <geometry> category is not a sub-category of <simulation> anymore but directly under <uFX_solver_deck>. This is especially relevant when using the <domain_part> entry, which will not be active if the <geometry> entries are listed under <simulation>.
  - <meshing>
    During meshing, ultraFluidX discretizes the volumetric simulation domain into cubic elements (“voxels”) for which the flow field is computed. The <meshing> category specifies the main parameters for the volume meshing and the refinement zones.
  - <boundary_conditions>
    This category specifies parameters for special types of boundaries.
  - <boundary_conditions> Revised Formulation
    As an extension to the solver deck entries mentioned above, ultraFluidX 2024.0 and beyond allows you to specify boundary conditions in a revised formulation to allow for more flexibility.
  - <sources>
    This category specifies parameters for volumetric sources (and sinks) of the following kinds: <porous>, <turbulence>, <mrf>, and <acoustic>.
  - <output>
    The <output> category specifies the main parameters for various types of simulation output.
- Expert Parameters
  Additional expert parameters can be used to fine-tune simulations.
- Post-Processing Tools
  For certain aeroacoustics applications, such as fan noise, HVAC noise and train community noise, you need to evaluate flow-induced noise levels at microphones located far away from the turbulent regions simulated in ultraFluidX.

View All Altair HyperWorks Help

Simulation Parameters

Available parameters for defining simulations in ultraFluidX.

ultraFluidX Solver Input Deck

The format for the ultraFluidX solver input deck is XML. The file starts with the XML prolog specifying the XML version and the character encoding:

<?xml version="1.0" encoding="UTF-8"?>

The prolog is followed by the root element,

<uFX_solver_deck name="ultraFluidX" xmlns="https://www.altair.com/ultrafluidx/”

which is parent to all other elements in the file, so the file must always end with </uFX_solver_deck> according to XML standards.

All categories and parameters must be specified in this way. The category or parameter, for example, always begins with a command of the format <example> and ends with the corresponding command </example>, with the respective child entries or the parameter specification in between.

The ultraFluidX solver input deck is grouped into five main categories: <simulation>, <meshing>, <boundary_conditions>, <sources> and <output>, each of them with several sub-categories and possible parameters as described below.

An example case (roadster.xml, roadster.stl) using the most important features including <rotating>, <belt>, <porous> and <probe_file> is located in the installation folder uFX/examples/roadster/.

Supported Parameters