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[piknockyou]

Subject: Request for Assistance in Combining ANSYS Mechanical .rst Files from Separate Simulations in Sequence

 

Dear Support Team/Forum Members,

 

I am reaching out to seek guidance or a potential solution for a specific challenge I am facing with ANSYS Mechanical APDL result files (.rst). My objective is to combine results from two separate simulations into a single .rst file, without performing any algebraic operations on the results themselves. I aim to achieve a sequential arrangement of Load Step results within one consolidated .rst file, akin to the outcome of running a single simulation with multiple Load Steps in sequence.

 

**Background:**

I have conducted two separate static structural analyses on the same finite element model, which shares identical geometry, material properties, mesh, and contact conditions. However, each simulation is subjected to a distinct load condition:

 

1. **Simulation 1:** Applies a force in the Z direction, resulting in a .rst file (let's call it `fileZ.rst`).

2. **Simulation 2:** Applies a force in the X direction, resulting in another .rst file (let's call it `fileX.rst`).

 

Each .rst file contains the results for its respective Load Step, and I can plot these results individually from each file in ANSYS Mechanical.

 

**Objective:**

My goal is to concatenate the Load Step results from `fileZ.rst` and `fileX.rst` into a single .rst file (let's call it `fileCombined.rst`). This file should contain the results of the Load Step from `fileZ.rst` followed by the results of the Load Step from `fileX.rst`, without any modification to the results data itself. The desired outcome is similar to what would be obtained if I had run a single simulation with two Load Steps in sequence: one for the Z direction force and another for the X direction force.

 

**Challenges:**

- I aim to avoid re-running the simulations due to their costly nature.

- Direct manipulation or merging of .rst files is not straightforward due to the structured and indexed format of ANSYS result files.

- ANSYS documentation and forums have not yielded a direct solution for merging .rst files from separate simulations in the manner described.

 

**Request:**

I am seeking advice, scripts, or methodologies that would enable me to achieve the aforementioned objective. Specifically, I am interested in any ANSYS Mechanical APDL commands, scripting techniques, or third-party tools that can facilitate the combination of .rst files as described, while preserving the integrity and sequential order of Load Step results.

 

If anyone has encountered a similar challenge or has insights into potential solutions, I would greatly appreciate your input. Additionally, if there are alternative approaches to analyzing combined effects of different load conditions without re-running simulations, I am open to suggestions.

 

Thank you in advance for your time and assistance.

 

Best regards,

 

 

[Avnish Pandey]

 

Hi,

Did you try using RESCOMBINE and RESWRITE commands. Below is the explanation to combine local results files into a global one when distributed solver is used.

You can use RESCOMBINE command in /POST1 to individually read each local results file until the entire set of results is placed into the database for postprocessing.

If needed, a subsequent RESWRITE command can then be issued to write a global results file for the distributed solution.

The following are the steps to use the RESCOMBINE command to combine slave node rst files:
1. read jobname.db file
2. use below commands to combine slave node files (currently 2 slave node files are used)
/post1
rescombine,2,jobname,rst,1
3. reswrite command to generate global rst file.

Ensure the two result files are in the same working directory and number them the way local result files get named for distributed solution (file0.rst, file1.rst and so on).

Check if this helps.