I am running a converging nozzle simulation in Fluent and I have used DEFINE_PROPERTY to define my own ideal gas law for density. When I run the simulation, the flow through the nozzle is isothermal. How can this be? When the flow accelerates, temperature should fall.
Tagged: 19.1, compressible-flow, fluent, fluid-dynamics, Modeling/Setup Advice
April 5, 2023 at 2:32 pmFAQParticipant
DEFINE_PROPERTY can be only be used to define density (as a function of temperature) for gases. Implementing a state law with DEFINE_PROPERTY drops the compressibility terms from the energy equation and will result in isothermal flow through the nozzle. To implement the full state equation, the example in the documentation entitled “Ideal Gas UDRGM Code Listing” (in the Fluent Customization Manual) should be used. This fulfills the requirement for thermodynamically consistent definitions for density and Cp. Thermodynamically consistent relationships for Density and Cp are ones that obey the state equation for Enthalpy. For a full explanation, please see the description in the CFX Theory Guide> Basic Solver Capability > Governing Equations > Equations of State > General Equation of State
Introducing Ansys Electronics Desktop on Ansys Cloud
The Watch & Learn video article provides an overview of cloud computing from Electronics Desktop and details the product licenses and subscriptions to ANSYS Cloud Service that are...
How to Create a Reflector for a Center High-Mounted Stop Lamp (CHMSL)
This video article demonstrates how to create a reflector for a center high-mounted stop lamp. Optical Part design in Ansys SPEOS enables the design and validation of multiple...
Introducing the GEKO Turbulence Model in Ansys Fluent
The GEKO (GEneralized K-Omega) turbulence model offers a flexible, robust, general-purpose approach to RANS turbulence modeling. Introducing 2 videos: Part 1 provides background information on the model and a...
Postprocessing on Ansys EnSight
This video demonstrates exporting data from Fluent in EnSight Case Gold format, and it reviews the basic postprocessing capabilities of EnSight.
- ANSYS Fluent: Introduction to the GEKO Turbulence Model Part I
- How can I create a Cell Register from a Cell Zone?
- ANSYS System Coupling: Two Way Fluid Structure Interaction – Part 1
- Delete or Deactivate Zone in Fluent
- Left-handed faces troubleshooting
- Running Python Script from Workbench
- ANSYS Polyflow: Adaptive Meshing Based on Contact
- Check CPU Time in ANSYS FLUENT
- How to overcome the model information incompatible with incoming mesh error?
- Apply Custom Material Properties in Fluent
© 2023 Copyright ANSYS, Inc. All rights reserved.