Tagged: convergence, thermal-analysis
June 6, 2022 at 9:58 amFAQParticipant
Here are some checks that can be useful to speedup convergence
1. If the initial temp of parts/regions close to the final temperature, it can decrease total # of iterations. (For Mechanical, the initial temperature can only be defined for the entire system, not per part. Either link another analysis where you solve a trivial condition of temp=X for part Y to be used as initial temperatures, or use a “Commands (APDL)” object with IC commands.
2. Tighten the radiosity solver tolerance. This may sound unintuitive, but the tighter the tolerance, the more accurate the heat fluxes that are passed back to MAPDL, meaning that you have fewer total iterations.
3. Try changing over-relaxation factor to 0.5. The radiative flux over-relaxation value uses a portion of the previous solution. The default is 0.1, which makes convergence slow since 90% of the previous solution is used. Since you have a radiation-dominant problem (i.e., only heat flow path between two bodies is via radiation), you probably don’t want to set it to 1.0 (use only currently-calculated values and not previous solution), but using a higher value than the default of 0.1 can help reduce total number of iterations.
It is advised to try each of these things, one at a time, to see which option has the biggest (positive) effect for particular case rather than changing all 3 at once.
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 Mechanical: Fatigue Crack Growth Analysis using SMART Crack Growth
- Does ECAD trace mapping support more than one type of trace material (usually copper) in the same layer?
- How can I understand Beam Probe results?
- Can the contact type (bonded or frictional) affect thermal results?
- Which time integration scheme is used in transient thermal analysis and how to change the scheme?
- Why there is difference in contact status between two load steps during Bolt Pretension? LS1: Bolt is Loaded LS2: Pretension is locked
- Static Structural Analysis of a Rear Upright – Part 1
- Modeling Radiative Heat Transfer
- What is pinball radius and does mesh size effect this value?
- How to define frictional coefficient as a function of relative sliding velocity
© 2023 Copyright ANSYS, Inc. All rights reserved.