> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ntop.com/llms.txt
> Use this file to discover all available pages before exploring further.

# How to export your design to Ansys Fluent

Here is a video demonstrating the workflow to export surface meshes of heat exchanger geometry from nTop for conjugate heat transfer analysis in ANSYS Fluent. This video covers assigning boundary conditions in nTop and volume meshing the solid and fluid domains in ANSYS Fluent. Prior to watching the video, it is recommended to go through the following courses on [nTop Learn](https://learn.ntop.com) to understand the process of designing and meshing complex geometry in nTop :

1. [Multicourse: Heat Exchanger Design](https://learn.ntop.com/courses/intro-to-two-channel-heat-exchangers-in-ntop/)
2. [102: Guide to Meshing](https://learn.ntop.com/courses/102-guide-to-meshing/)
3. [Surface Meshing Best Practices](https://learn.ntop.com/courses/surface-meshing-techniques/)

**Merge**

Here are the TUI Commands for merging multiple surfaces into a water-tight domain that can be pasted in the ANSYS Console for this example :

* objects/merge cold\_wall cold\_solid\_int cold\_inlet cold\_outlet () cold\_fluid
* objects/merge hot\_wall hot\_solid\_int hot\_inlet hot\_outlet () hot\_fluid
* objects/merge solid\_wall solid\_hot\_int solid\_cold\_int () solid\_hex

The general syntax is “*objects/merge \[boundary name 1] \[boundary name 2] () \[desired domain name]*” . The boundary names will have to correspond to names assigned in nTop. The desired domain name is the name of the merged object.

![The Ansys console](https://files.learn.ntop.com/help-articles/interop/34046744850835.png)

**Label**

Here are the TUI Commands for extracting the zone labels of the water-tight domain that can be pasted into the ANSYS Console for this example :

* objects/labels/create-label-per-zone cold\_fluid cold\_solid\_int.1 cold\_outlet.1 cold\_inlet.1 cold\_wall.1 ()
* objects/labels/create-label-per-zone hot\_fluid hot\_solid\_int.1 hot\_outlet.1 hot\_inlet.1 hot\_wall.1 ()
* objects/labels/create-label-per-zone solid\_hex solid\_cold\_int.1 solid\_hot\_int.1 solid\_wall.1 ()

The general syntax is “*objects/labels/create-label-zone \[boundary name 1].1 \[boundary name 2].1 ()*”

**Relevant Files**

[nTop Example File](https://files.learn.ntop.com/Support%20Article%20Example%20Files/Knowledge%20Base/User%20Interface/Export%20to%20Ansys%20Fluent%20Example.ntop)

[Solved ANSYS File](https://files.learn.ntop.com/Support%20Article%20Example%20Files/Knowledge%20Base/User%20Interface/Solved%20Ansys%20Fluent%20Example.zip)

## Keywords:

*analysis export ansys fluent cfd*