# Multi-structure Fluid-Structure Interaction
**URL:** https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659
**Category:** Using preCICE
**Tags:** openfoam, calculix, fsi
**Created:** [November 5, 2025, 7:13am UTC](https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659 "2025-11-05T07:13:48Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@HHao-gihub](https://precice.discourse.group/u/HHao-gihub)
#### Post date: [November 5, 2025, 7:13am UTC](https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659/1 "2025-11-05T07:13:48Z")
The official Precice example provides a multi-structure fluid-structure interaction coupling between OpenFOAM and Dealii. I want to use Calculix instead of Dealii. How should I proceed? Do I need to run two structural terminals?
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### Author:  [@fsimonis](https://precice.discourse.group/u/fsimonis)
#### Post date: [November 5, 2025, 12:17pm UTC](https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659/2 "2025-11-05T12:17:26Z")
Hi,
You are probably referring to the following tutorial:
> **[Multiple perpendicular flaps](https://precice.org/tutorials-multiple-perpendicular-flaps.html)**
>
> In this case, a fluid and two solids are coupled together using a fully-implicit multi-coupling scheme.
> Do I need to run two structural terminals?
Yes, every participant / solver runs separately. Running it in separate terminals is useful to understand this concept.
> I want to use Calculix instead of Dealii. How should I proceed?
You can take a look at the (single) perpendicular flap tutorial, which is available for many solvers.
Then copy the solid-calculix folder over, adjust input geometry, and adapter settings such as mesh and data names.
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### Author:  [@HHao-gihub](https://precice.discourse.group/u/HHao-gihub)
#### Post date: [November 6, 2025, 3:17am UTC](https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659/3 "2025-11-06T03:17:11Z")
Thank you for your response. I’ve already resolved the issue.
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### Author:  [@Makis](https://precice.discourse.group/u/Makis)
#### Post date: [November 6, 2025, 8:25am UTC](https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659/4 "2025-11-06T08:25:19Z")
@HHao-gihub that’s good to hear! If you ported the tutorial to CalculiX, we would be happy to merge any such contribution to the tutorials repository.
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### Author:  [@system](https://precice.discourse.group/u/system)
#### Post date: [November 9, 2025, 8:25am UTC](https://precice.discourse.group/t/multi-structure-fluid-structure-interaction/2659/5 "2025-11-09T08:25:22Z")
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