-
-
October 19, 2023 at 12:27 pm
Diogo Martinho
SubscriberHey all,
I will try to explain this shortly:
I have two phases, liquid and gas. Liquid has 5 different components, gas has 3 different components. So, in my opinion I have two different background species. One for the liquid phase, one for the gas phase.
All my domains are porous. However, no capillary pressure, contact angle, relative permeability is being defined. Only porosity and permeability of the domain.
While the liquid phase runs well and the results seem to make sense, when I look at the secondary phase the same does not happen.
The idea is the system will reach some concentrations and then there will be some phase change. So, when I initialize, two species (resulting from governing equations) are set to 0 mass fraction in the gas phase. Then, I would expect to have the third one (last species) to be 1 and to be solved algebraically. However, after two iterations something strange starts to happen (see figures). the simulation runs but in the centered domain the results show a non-balance in terms of mass fraction.
Any comments?
Kind regards,
Diogo -
October 27, 2023 at 6:39 am
SRP
Ansys EmployeeHi,
The strange behavior you're observing may be due to various reasons, such as numerical stability, boundary conditions, or issues with your phase change modeling. Verify that your numerical solver and time-stepping scheme are stable for the given problem.Ensure that your boundary conditions for the phases and species are correctly set up.
Thank you.
-
- You must be logged in to reply to this topic.

Boost Ansys Fluent Simulations with AWS
Computational Fluid Dynamics (CFD) helps engineers design products in which the flow of fluid components is a significant challenge. These different use cases often require large complex models to solve on a traditional workstation. Click here to join this event to learn how to leverage Ansys Fluids on the cloud, thanks to Ansys Gateway powered by AWS.

Earth Rescue – An Ansys Online Series
The climate crisis is here. But so is the human ingenuity to fight it. Earth Rescue reveals what visionary companies are doing today to engineer radical new ideas in the fight against climate change. Click here to watch the first episode.

Ansys Blog
Subscribe to the Ansys Blog to get great new content about the power of simulation delivered right to your email on a weekly basis. With content from Ansys experts, partners and customers you will learn about product development advances, thought leadership and trends and tips to better use Ansys tools. Sign up here.
- Floating point exception in Fluent
- What are the differences between CFX and Fluent?
- Heat transfer coefficient
- Difference between K-epsilon and K-omega Turbulence Model
- Getting graph and tabular data from result in workbench mechanical
- The solver failed with a non-zero exit code of : 2
- Time Step Size and Courant Number
- Mesh Interfaces in ANSYS FLUENT
- Suppress Fluent to open with GUI while performing in journal file
- error: Received signal SIGSEGV
-
8786
-
4658
-
3151
-
1678
-
1468
© 2023 Copyright ANSYS, Inc. All rights reserved.