# Possibility of separate processes for mesh sub-domains in a single simulation

**URL:** <https://discourse.opengeosys.org/t/possibility-of-separate-processes-for-mesh-sub-domains-in-a-single-simulation/1783>\
**Category:** Help & Support\
**Created:** [December 19, 2025, 12:27pm UTC](https://discourse.opengeosys.org/t/possibility-of-separate-processes-for-mesh-sub-domains-in-a-single-simulation/1783 "2025-12-19T12:27:41Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![marosaro](https://discourse.opengeosys.org/letter_avatar_proxy/v4/letter/m/5e9695/32.png) [@marosaro](https://discourse.opengeosys.org/u/marosaro)\
**Post date:** [December 19, 2025, 12:27pm UTC](https://discourse.opengeosys.org/t/possibility-of-separate-processes-for-mesh-sub-domains-in-a-single-simulation/1783/1 "2025-12-19T12:27:41Z")

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Hello everybody,

Is it possible to have multiple processes which are done on different subdomains inside 1 project file/1 simulation?

E.g. if we want to simulate HT process for the reservoir and in parallel WELLBORE\_SIMULATOR process for a 1D mesh of the wellbore inside the main domain?  
Since for every timestep, WELLBORE\_SIMULATOR inputs should depend on the reservoir simulation results (for that timestep).

Thank you and best regards

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**Author:** ![thomas.fischer](https://discourse.opengeosys.org/user_avatar/discourse.opengeosys.org/thomas.fischer/32/416_2.png) [@thomas.fischer](https://discourse.opengeosys.org/u/thomas.fischer)\
**Post date:** [January 6, 2026, 9:34am UTC](https://discourse.opengeosys.org/t/possibility-of-separate-processes-for-mesh-sub-domains-in-a-single-simulation/1783/2 "2026-01-06T09:34:36Z")

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Did you have a look at the [HeatTransportBHE process in OGS](https://www.opengeosys.org/stable/docs/processes/heat-transport/heat_transport_bhe/)? In our view this would be a simpler approach for you. Or is there a feature missing in this OGS process.

> [@marosaro](#):
>
> Is it possible to have multiple processes which are done on different subdomains inside 1 project file/1 simulation?

Yes, this is a known limitation of our Cosim interface at the moment. But lets start with the heat transport process including BHE in ogs first.

Tobias and Tom