##  [Ansys Thermal Desktop - Previous releases](/docs/thermal-desktop/previous) 

## Documentation

###### OpenTD guide

Use this guide to learn the OpenTD API concepts and syntax through a series of example C# programs.

[2025 R2](/docs/opentd-2025-r2/index.md)

[92.0.0.0](/docs/opentd-92-0-0-0/index.md)

[2024 R2](/docs/opentd-2024-r2/index.md)





 

 



###### OpenTD reference

Download this API reference for a comprehensive list of all OpenTD API types and methods.

[2025 R2 - Net4](/docs/opentd-net4-reference-2025-r2/index.xhtml)

[2025 R2 - Net8](/docs/opentd-net8-reference-2025-r2/index.xhtml)

[92.0.0.0](https://github.com/ansys/DevRelPublic/raw/main/Downloads/Thermal-Desktop-OpenTD/92.0.0.0/OpenTDv920000-Class-Reference.chm)

[2024 R2](https://github.com/ansys/DevRelPublic/raw/main/Downloads/Thermal-Desktop-OpenTD/2024R2/OpenTDv242-Class-Reference.chm)





 

 



###### OpenTD demos

Download this Visual Studio C# project showcasing multiple usage scenarios with the OpenTD API.

[2025 R2 Net4](https://github.com/ansys/DevRelPublic/raw/main/Downloads/Thermal-Desktop-OpenTD/2025R2-Net4.zip)

[92.0.0.0](https://github.com/ansys/DevRelPublic/raw/main/Downloads/Thermal-Desktop-OpenTD/92.0.0.0/OpenTDv92000-Demos01.zip)

[2024 R2](https://github.com/ansys/DevRelPublic/raw/main/Downloads/Thermal-Desktop-OpenTD/2024R2/OpenTDv242Demos01.zip)