session_utilities

Session utilities.

Classes:

Meshing()	Encapsulates a Fluent server for meshing session connection.
PrePost()	Encapsulates a Fluent server for pre-post session connection.
PureMeshing()	Encapsulates a Fluent server for pure meshing session connection.
SessionBase()	Base class for Fluent sessions.
Solver()	Encapsulates a Fluent server for solver session connection.
SolverAero()	Encapsulates a Fluent server for solver aero session connection.
SolverIcing()	Encapsulates a Fluent server for solver icing session connection.

class ansys.fluent.core.session_utilities.Meshing

Bases: SessionBase

Encapsulates a Fluent server for meshing session connection.

class ansys.fluent.core.session_utilities.PrePost

Bases: SessionBase

Encapsulates a Fluent server for pre-post session connection.

class ansys.fluent.core.session_utilities.PureMeshing

Bases: SessionBase

Encapsulates a Fluent server for pure meshing session connection.

class ansys.fluent.core.session_utilities.SessionBase

Bases: object

Base class for Fluent sessions.

This class is not intended to be used directly. Instead, use the from_connection, from_container, from_install, or from_pim functions to create a session.

Methods:

from_connection([ip, port, ...])	Connect to an existing Fluent server instance.
from_container([ui_mode, graphics_driver, ...])	Launch a Fluent session in container mode.
from_install([ui_mode, graphics_driver, ...])	Launch a Fluent session in standalone mode.
from_pim([ui_mode, graphics_driver, ...])	Launch a Fluent session in PIM mode.

classmethod from_connection(ip=None, port=None, server_info_file_name=None, password=None)

Connect to an existing Fluent server instance.

Parameters:

ipstr, optional

IP address for connecting to an existing Fluent instance. The IP address defaults to "127.0.0.1". You can also use the environment variable PYFLUENT_FLUENT_IP=<ip> to set this parameter. The explicit value of ip takes precedence over PYFLUENT_FLUENT_IP=<ip>.

portint, optional

Port to listen on for an existing Fluent instance. You can use the environment variable PYFLUENT_FLUENT_PORT=<port> to set a default value. The explicit value of port takes precedence over PYFLUENT_FLUENT_PORT=<port>.

server_info_file_name: str

Path to server-info file written out by Fluent server. The default is None. PyFluent uses the connection information in the file to connect to a running Fluent session.

passwordstr, optional

Password to connect to existing Fluent instance.

Raises:

TypeError

If the session type does not match the expected session type.

classmethod from_container(ui_mode=None, graphics_driver=None, product_version=None, dimension=None, precision=None, processor_count=None, start_timeout=60, additional_arguments='', container_dict=None, dry_run=False, cleanup_on_exit=True, start_transcript=True, py=None, gpu=None, start_watchdog=None, file_transfer_service=None)

Launch a Fluent session in container mode.

Parameters:

ui_modeUIMode

Defines the user interface mode for Fluent. Options correspond to values in the UIMode enum.

graphics_driverFluentWindowsGraphicsDriver or FluentLinuxGraphicsDriver

Specifies the graphics driver for Fluent. Options are from the FluentWindowsGraphicsDriver enum (for Windows) or the FluentLinuxGraphicsDriver enum (for Linux).

product_versionFluentVersion or str or float or int, optional

Indicates the version of Ansys Fluent to launch. For example, to use version 2025 R1, pass any of FluentVersion.v251, "25.1.0", "25.1", 25.1, or 251. Defaults to None, which uses the newest installed version.

dimensionDimension or int, optional

Specifies the geometric dimensionality of the Fluent simulation. Defaults to None, which corresponds to Dimension.THREE. Acceptable values include Dimension.TWO, Dimension.THREE, or integers 2 and 3.

precisionPrecision or str, optional

Defines the floating point precision. Defaults to None, which corresponds to Precision.DOUBLE. Acceptable values include Precision.SINGLE, Precision.DOUBLE, or strings "single" and "double".

processor_countint, optional

Specifies the number of processors to use. Defaults to None, which uses 1 processor. In job scheduler environments, this value limits the total number of allocated cores.

start_timeoutint, optional

Maximum allowable time in seconds for connecting to the Fluent server. Defaults to 60 seconds.

additional_argumentsstr, optional

Additional command-line arguments for Fluent, formatted as they would be on the command line.

container_dictdict, optional

Configuration dictionary for launching Fluent inside a Docker container. See also fluent_container.

dry_runbool, optional

If True, does not launch Fluent but prints configuration information instead. If dry running a container start, this method will return the configured container_dict. Defaults to False.

cleanup_on_exitbool

Determines whether to shut down the connected Fluent session upon exit or when calling the session’s exit() method. Defaults to True.

start_transcriptbool

Indicates whether to start streaming the Fluent transcript in the client. Defaults to True; streaming can be controlled via transcript.start() and transcript.stop() methods on the session object.

pybool, optional

If True, runs Fluent in Python mode. Defaults to None.

gpubool, optional

If True, starts Fluent with GPU Solver enabled.

start_watchdogbool, optional

If True and cleanup_on_exit is True, an independent watchdog process is run to ensure that any local GUI-less Fluent sessions started by PyFluent are properly closed when the current Python process ends.

file_transfer_serviceAny, optional

Service for uploading/downloading files to/from the server.

Returns:

Meshing | PureMeshing | Solver | SolverIcing | dict

Session object or configuration dictionary if dry_run is True.

Raises:

UnexpectedKeywordArgument

If an unexpected keyword argument is provided.

Notes

In job scheduler environments (e.g., SLURM, LSF, PBS), resources and compute nodes are allocated, and core counts are queried from these environments before being passed to Fluent.

classmethod from_install(ui_mode=None, graphics_driver=None, product_version=None, dimension=None, precision=None, processor_count=None, journal_file_names=None, start_timeout=60, additional_arguments='', env={}, cleanup_on_exit=True, dry_run=False, start_transcript=True, case_file_name=None, case_data_file_name=None, lightweight_mode=None, py=None, gpu=None, cwd=None, fluent_path=None, topy=None, start_watchdog=None, file_transfer_service=None)

Launch a Fluent session in standalone mode.

Parameters:

ui_modeUIMode

Defines the user interface mode for Fluent. Options correspond to values in the UIMode enum.

graphics_driverFluentWindowsGraphicsDriver or FluentLinuxGraphicsDriver

Specifies the graphics driver for Fluent. Options are from the FluentWindowsGraphicsDriver enum (for Windows) or the FluentLinuxGraphicsDriver enum (for Linux).

product_versionFluentVersion or str or float or int, optional

Indicates the version of Ansys Fluent to launch. For example, to use version 2025 R1, pass FluentVersion.v251, "25.1.0", "25.1", 25.1, or 251. Defaults to None, which uses the newest installed version.

dimensionDimension or int, optional

Specifies the geometric dimensionality of the Fluent simulation. Defaults to None, which corresponds to Dimension.THREE. Acceptable values are from the Dimension enum (Dimension.TWO or Dimension.THREE) or integers 2 and 3.

precisionPrecision or str, optional

Defines the floating point precision. Defaults to None, which corresponds to Precision.DOUBLE. Acceptable values are from the Precision enum (Precision.SINGLE or Precision.DOUBLE) or strings "single" and "double".

processor_countint, optional

Specifies the number of processors to use. Defaults to None, which uses 1 processor. In job scheduler environments, this value limits the total number of allocated cores.

journal_file_namesstr or list of str, optional

Path(s) to a Fluent journal file(s) that Fluent will execute. Defaults to None.

start_timeoutint, optional

Maximum time in seconds allowed for connecting to the Fluent server. Defaults to 60 seconds.

additional_argumentsstr, optional

Additional command-line arguments for Fluent, formatted as they would be on the command line.

envdict[str, str], optional

A mapping for modifying environment variables in Fluent. Defaults to None.

cleanup_on_exitbool, optional

Determines whether to shut down the connected Fluent session when exiting PyFluent or calling the session’s exit() method. Defaults to True.

dry_runbool, optional

If True, does not launch Fluent but prints configuration information instead. The call() method returns a tuple containing the launch string and server info file name. Defaults to False.

start_transcriptbool, optional

Indicates whether to start streaming the Fluent transcript in the client. Defaults to True; streaming can be controlled via transcript.start() and transcript.stop() methods on the session object.

case_file_namestr, optional

Name of the case file to read into the Fluent session. Defaults to None.

case_data_file_namestr, optional

Name of the case data file. If both case and data files are provided, they are read into the session.

lightweight_modebool, optional

If True, runs in lightweight mode where mesh settings are read into a background solver session, replacing it once complete. This parameter is only applicable when case_file_name is provided; defaults to False.

pybool, optional

If True, runs Fluent in Python mode. Defaults to None.

gpubool, optional

If True, starts Fluent with GPU Solver enabled.

cwdstr, optional

Working directory for the Fluent client.

fluent_path: str, optional

User-specified path for Fluent installation.

topybool or str, optional

A flag indicating whether to write equivalent Python journals from provided journal files; can also specify a filename for the new Python journal.

start_watchdogbool, optional

When cleanup_on_exit is True, defaults to True; an independent watchdog process ensures that any local GUI-less Fluent sessions started by PyFluent are properly closed when the current Python process ends.

file_transfer_serviceAny

Service for uploading/downloading files to/from the server.

Raises:

UnexpectedKeywordArgument

If an unexpected keyword argument is provided.

Notes

In job scheduler environments (e.g., SLURM, LSF, PBS), resources and compute nodes are allocated, and core counts are queried from these environments before being passed to Fluent.

classmethod from_pim(ui_mode=None, graphics_driver=None, product_version=None, dimension=None, precision=None, processor_count=None, start_timeout=60, additional_arguments='', cleanup_on_exit=True, dry_run=None, start_transcript=True, gpu=None, start_watchdog=None, file_transfer_service=None)

Launch a Fluent session in PIM mode.

Parameters:

ui_modeUIMode or str, optional

Defines the user interface mode for Fluent. Options correspond to values in the UIMode enum.

graphics_driverFluentWindowsGraphicsDriver or FluentLinuxGraphicsDriver

Specifies the graphics driver for Fluent. Options are from the FluentWindowsGraphicsDriver enum (for Windows) or the FluentLinuxGraphicsDriver enum (for Linux).

product_versionFluentVersion or str or float or int, optional

Indicates the version of Ansys Fluent to launch. For example, to use version 2025 R1, pass any of FluentVersion.v251, "25.1.0", "25.1", 25.1, or 251. Defaults to None, which uses the newest installed version.

dimensionDimension or int, optional

Specifies the geometric dimensionality of the Fluent simulation. Defaults to None, which corresponds to Dimension.THREE. Acceptable values include Dimension.TWO, Dimension.THREE, or integers 2 and 3.

precisionPrecision or str, optional

Defines the floating point precision. Defaults to None, which corresponds to Precision.DOUBLE. Acceptable values include Precision.SINGLE, Precision.DOUBLE, or strings "single" and "double".

processor_countint, optional

Specifies the number of processors to use. Defaults to None, which uses 1 processor. In job scheduler environments, this value limits the total number of allocated cores.

start_timeoutint, optional

Maximum allowable time in seconds for connecting to the Fluent server. Defaults to 60 seconds.

additional_argumentsstr, optional

Additional command-line arguments for Fluent, formatted as they would be on the command line.

cleanup_on_exitbool

Determines whether to shut down the connected Fluent session upon exit or when calling the session’s exit() method. Defaults to True.

dry_runbool, optional

If True, does not launch Fluent but prints configuration information instead. If dry running a PIM start, this method will return a configuration dictionary. Defaults to False.

start_transcriptbool

Indicates whether to start streaming the Fluent transcript in the client. Defaults to True; streaming can be controlled via transcript.start() and transcript.stop() methods on the session object.

gpubool, optional

If True, starts Fluent with GPU Solver enabled.

start_watchdogbool, optional

If True and cleanup_on_exit is True, an independent watchdog process is run to ensure that any local GUI-less Fluent sessions started by PyFluent are properly closed when the current Python process ends.

file_transfer_serviceAny, optional

Service for uploading/downloading files to/from the server.

Returns:

Union[Meshing, PureMeshing, Solver, SolverIcing, dict]

Session object or configuration dictionary if dry_run is True.

Raises:

UnexpectedKeywordArgument

If an unexpected keyword argument is provided.

Notes

In job scheduler environments (e.g., SLURM, LSF, PBS), resources and compute nodes are allocated, and core counts are queried from these environments before being passed to Fluent.

class ansys.fluent.core.session_utilities.Solver

Bases: SessionBase

Encapsulates a Fluent server for solver session connection.

class ansys.fluent.core.session_utilities.SolverAero

Bases: SessionBase

Encapsulates a Fluent server for solver aero session connection.

class ansys.fluent.core.session_utilities.SolverIcing

Bases: SessionBase

Encapsulates a Fluent server for solver icing session connection.