-
-
September 22, 2022 at 8:24 pm
Jayachandran Narayanan
SubscriberHello,
We are trying to simulate the chilldown process of liquid nitrogen through a pipe. The simulation includes both fluid and solid regions (pipe dimensions). Mixture model along with dispersed option has been selected for modeling the multiphase flow. We are trying to simulate the film boiling phase of the cryogenic chilldown process by adjusting the Lee coefficients. It has been observed that Lee coefficient value of around 1000 with first order accurate time and space schemes provides the closest estimate of the solid temperature distribution. But, due to the diffusive nature of the first order schemes, we need second order time and space stepping, but the simulations run smoothly upto Lee coefficent of around 100 and diverges above values of 100 with the second order schemes. The second order simulations are running around 1.5-2s (10^-4s time step size) and then diverging. Hence, the use of first order schemes for stabilising the simulation may not work for our case. Kindly help to resolve this issue.
-
September 26, 2022 at 4:00 pm
Rob
Ansys EmployeeThe coefficients are a frequency unit so try with a smaller time step: you may be moving mass too quickly for the current time step.
-
- You must be logged in to reply to this topic.

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.
- Suppress Fluent to open with GUI while performing in journal file
- Floating point exception in Fluent
- What are the differences between CFX and Fluent?
- Heat transfer coefficient
- Getting graph and tabular data from result in workbench mechanical
- The solver failed with a non-zero exit code of : 2
- Difference between K-epsilon and K-omega Turbulence Model
- Time Step Size and Courant Number
- Mesh Interfaces in ANSYS FLUENT
- error in cfd post
-
2524
-
2066
-
1279
-
1096
-
457
© 2023 Copyright ANSYS, Inc. All rights reserved.