Solver Configuration Hooks

The solver configuration hooks allow plugins to configure internal settings from ALFAsim. To add a configuration hook it is necessary to implement the given hook in a python file that is already available on your plugin project folder.

As an example, if a plugin was created using alfasim-sdk template command and named as myplugin the necessary file to be customized would be located on: myplugin ‣ src ‣ python ‣ myplugin.py

Additional Variables

alfasim_get_additional_variables()

Allows plugins to register new additional variables on ALFAsim.

It can be used to store the internal variable from the plugin (on solver), or it can be used to expose as an output to the user in the plot window (on application). To calculate and update the registered variables the Solver hooks described on Update plugin variables section must be implemented.

This method expects to return a list of alfasim_sdk.variables.SecondaryVariable(), for more details checkout the reference section with all details about variables

Usage example:

from alfasim_sdk import SecondaryVariable
from alfasim_sdk import Visibility
from alfasim_sdk import Location
from alfasim_sdk import Scope

@alfasim_sdk.hookimpl
def alfasim_get_additional_variables():
    return [
        SecondaryVariable(
            name='dummy_variable',
            caption='Plugin 1',
            unit='m',
            visibility=Visibility.Internal,
            location=Location.Center,
            multifield_scope=Scope.Global,
            checked_on_gui_default=True,
        )]

Hydrodynamic Model

ALFAsim provides a way to customize the hydrodynamic model available within the application, with the usage of the hook listed below, the plugin can:

• Add new fields

• Add/update phases

• Add/update layers

Note

For each new added field is considered a mass conservation equation and for each new added layer is considered a momentum conservation and an energy conservation equations, depending on the energy model used at ALFAsim.

alfasim_configure_fields()

Allows plugins to configure new fields to be added in ALFAsim’s hydrodynamic model.

An added field must be associated with:

• Phase, defined by AddPhase or UpdatePhase.

• Layer, defined by AddLayer or UpdateLayer.

Example of usage:

@alfasim_sdk.hookimpl
def alfasim_configure_fields():
   return [
       AddField(name='plugin_continuous_field'),
       AddField(name='plugin_dispersed_field'),
   ]

alfasim_configure_phases()

Allows plugins to configure new phases or associate a new field with a existing phase from the application. In order to configure a new phase it is necessary to return an AddPhase object defining the required fields.

Example of usage:

@alfasim_sdk.hookimpl
def alfasim_configure_phases():
    return [
        AddPhase(
            name='plugin_phase',
            fields=[
                'plugin_continuous_field',
                'plugin_dispersed_field',
            ],
            primary_field='plugin_continuous_field',
            is_solid=False,
        )
    ]

With this new phase, all existing hydrodynamic models from the application will have this additional phase. Notice that the fields parameter must be a field registered from the hook alfasim_configure_fields().

Note

You can restrict the operation of your plugin in the application to certain settings by using the status monitor. For example, if your plugin does not work with the water phase you can block the simulation if the user is using a hydrodynamic model with water.

For more details check out the documentation of alfasim_get_status()

The image below shows the new added phase on the application.

It is also possible to add additional fields to existent phases using the UpdatePhase.

Example of usage:

@alfasim_sdk.hookimpl
def alfasim_configure_phases():
    return [
        UpdatePhase(
            name=OIL_PHASE,
            additional_fields=['plugin_dispersed_field'],
        )
    ]

alfasim_configure_layers()

Allows plugins to configure new layers or associate a new field with a existing layer for ALFAsim’s hydrodynamic model

In order to configure a new layer, it is necessary to return an AddLayer object defining the required fields.

Example of usage:

@alfasim_sdk.hookimpl
def alfasim_configure_layers():
   return [
       AddLayer(
           name='plugin_layer',
           fields=['plugin_continuous_field'],
           continuous_field='plugin_continuous_field',
       ),
       UpdateLayer(
           name=OIL_LAYER,
           additional_fields=['plugin_dispersed_field'],
       ),
   ]

The image below shows the new added phase on the application.

In order to complement the Hydrodynamic model customization, it is possible to inform ALFAsim which phases (added from plugin or not) will have the state variables calculated by plugin.

alfasim_get_phase_properties_calculated_from_plugin()

Allows the plugin to calculate the properties (state variables) of a phase.

Must return a list of phase names in which state variables will be computed for. If the plugin implements this hook four C/C++ Solver hooks also must be implemented. They are:

• HOOK_INITIALIZE_STATE_VARIABLE_CALCULATOR

• HOOK_CALCULATE_STATE_VARIABLE

• HOOK_CALCULATE_PHASE_PAIR_STATE_VARIABLE

• HOOK_FINALIZE_STATE_VARIABLE_CALCULATOR

The first and last hooks are called immediately before and after the state variables are calculated, respectively.

Example of usage:

from alfasim_sdk import GAS_PHASE

@alfasim_sdk.hookimpl
def alfasim_get_phase_properties_calculated_from_plugin():
    return [GAS_PHASE, 'solid']

alfasim_get_phase_interaction_properties_calculated_from_plugin()

Allows the plugin to calculate the properties that are related to a pair of phases, like surface tension.

Must return a list of tuple of phases in which state variables will be computed for. In order to implement the properties, HOOK_CALCULATE_PHASE_PAIR_STATE_VARIABLE must be implemented on the C/C++ part of the plugin.

Example of usage:

from alfasim_sdk import GAS_PHASE, OIL_PHASE, WATER_PHASE

@alfasim_sdk.hookimpl
def alfasim_get_phase_interaction_properties_calculated_from_plugin():
return [
    (GAS_PHASE, OIL_PHASE),
    (GAS_PHASE, WATER_PHASE),
]

User Defined Tracers

Warning

This is advanced customization. We strongly encourage the plugin developer to read the Tracers chapter of ALFAsim’s Technical Report available on the Help menu at ALFAsim application.

alfasim_get_user_defined_tracers_from_plugin()

Allows the plugin to add new tracers in the ALFAsim’s Tracer Solver, in which the transport equation will be modified by Solver hooks listed below.

Must return a list of tracers in which the internal tracer model hooks will be implemented. The following C/C++ Solver hooks must be implemented:

• HOOK_INITIALIZE_MASS_FRACTION_OF_TRACER

• HOOK_COMPUTE_MASS_FRACTION_OF_TRACER_IN_PHASE

• HOOK_COMPUTE_MASS_FRACTION_OF_TRACER_IN_FIELD

• HOOK_SET_BOUNDARY_CONDITION_OF_MASS_FRACTION_OF_TRACER

• HOOK_UPDATE_BOUNDARY_CONDITION_OF_MASS_FRACTION_OF_TRACER

Example of usage:

@alfasim_sdk.hookimpl
def alfasim_get_user_defined_tracers_from_plugin():
    return ['my_tracer']

Note

The tracer added in the user-defined tracers from plugin list will not be considered as a standard tracer, which has an output of its mass fraction and appears in the tracer container at ALFAsim’s User Interface. The user-defined tracer is hidden (does not appear in the User Interface) and the plugin developer can modify the transport equation to use its results internally. However, the user-defined tracers will be solved together with the standard tracers (Added via User Interface).

Application Hooks Solver Hooks