refactor: use new fluidstream object in compressor models and results (#1006)

* refactor: use new FluidStream object in compressor calculations and results

* refactor: replace TrainFluidStream with FluidFactoryInterface dependency injection

This commit implements a comprehensive refactoring to replace the old
TrainFluidStream with a new FluidFactoryInterface pattern that moves
toward Domain-Driven Design principles.

Refs.
equinor/ecalc-internal#610
equinor/ecalc-internal#641

Author: kjbrak

src/ecalc_neqsim_wrapper/mappings.py

@@ -2,10 +2,10 @@
 
 from pydantic import Field
 
+from libecalc.common.ecalc_base_model import EcalcBaseModel
 from libecalc.common.errors.exceptions import EcalcError
-from libecalc.common.fluid import EcalcBaseModel
 from libecalc.common.logger import logger
-from libecalc.domain.process.value_objects.fluid_stream.fluid_composition import FluidComposition
+from libecalc.domain.process.value_objects.fluid_stream.fluid_model import FluidComposition
 
 
 class NeqsimComposition(EcalcBaseModel):

src/ecalc_neqsim_wrapper/thermo.py

@@ -20,8 +20,7 @@
 )
 from libecalc.common.decorators.capturer import Capturer
 from libecalc.common.logger import logger
-from libecalc.domain.process.value_objects.fluid_stream.eos_model import EoSModel
-from libecalc.domain.process.value_objects.fluid_stream.fluid_composition import FluidComposition
+from libecalc.domain.process.value_objects.fluid_stream.fluid_model import EoSModel, FluidComposition
 
 STANDARD_TEMPERATURE_KELVIN = 288.15
 STANDARD_PRESSURE_BARA = 1.01325

src/libecalc/common/ecalc_base_model.py

@@ -0,0 +1,11 @@
+from pydantic import BaseModel, ConfigDict
+
+from libecalc.common.string.string_utils import to_camel_case
+
+
+class EcalcBaseModel(BaseModel):
+    model_config = ConfigDict(
+        extra="forbid",
+        alias_generator=to_camel_case,
+        populate_by_name=True,
+    )

src/libecalc/common/fluid.py

@@ -1,13 +1,10 @@
 from typing import Any
 
 from libecalc.common.energy_model_type import EnergyModelType
-from libecalc.common.fluid import MultipleStreamsAndPressureStream
-from libecalc.common.fluid_stream_type import FluidStreamType
 from libecalc.common.logger import logger
 from libecalc.domain.infrastructure.energy_components.turbine import Turbine
 from libecalc.domain.process.compressor.core.base import CompressorModel, CompressorWithTurbineModel
 from libecalc.domain.process.compressor.core.sampled import CompressorModelSampled
-from libecalc.domain.process.compressor.core.train.fluid import FluidStream
 from libecalc.domain.process.compressor.core.train.simplified_train import (
     CompressorTrainSimplifiedKnownStages,
     CompressorTrainSimplifiedUnknownStages,
@@ -32,6 +29,20 @@
     VariableSpeedCompressorTrainMultipleStreamsAndPressures,
 )
 from libecalc.domain.process.compressor.dto.model_types import CompressorModelTypes as CompressorModelDTO
+from libecalc.domain.process.value_objects.fluid_stream.fluid_factory import FluidFactoryInterface
+from libecalc.domain.process.value_objects.fluid_stream.fluid_model import FluidModel
+from libecalc.domain.process.value_objects.fluid_stream.multiple_streams_stream import (
+    FluidStreamType,
+    MultipleStreamsAndPressureStream,
+)
+from libecalc.infrastructure.neqsim_fluid_provider.neqsim_fluid_factory import NeqSimFluidFactory
+
+
+def _create_fluid_factory(fluid_model: FluidModel | None) -> FluidFactoryInterface | None:
+    """Create a fluid factory from a fluid model."""
+    if fluid_model is None:
+        return None
+    return NeqSimFluidFactory(fluid_model)
 
 
 def _create_variable_speed_compressor_train_multiple_streams_and_pressures_stream(
@@ -41,7 +52,7 @@ def _create_variable_speed_compressor_train_multiple_streams_and_pressures_strea
     is_inlet_stream = stream_data.typ == FluidStreamType.INGOING
     return FluidStreamObjectForMultipleStreams(
         name=stream_data.name,
-        fluid=FluidStream(fluid_model=stream_data.fluid_model) if stream_data.fluid_model else None,
+        fluid_model=stream_data.fluid_model,
         is_inlet_stream=is_inlet_stream,
         connected_to_stage_no=stream_references[stream_data.name],
     )
@@ -52,8 +63,12 @@ def _create_compressor_train_simplified_with_known_stages(
 ) -> CompressorTrainSimplifiedKnownStages:
     # Energy usage adjustment not supported for this model (yet)
     # Issue error if factors are not default (and not changing the energy usage result)
+    fluid_factory = _create_fluid_factory(compressor_model_dto.fluid_model)
+    if fluid_factory is None:
+        raise ValueError("Fluid model is required for compressor train")
     return CompressorTrainSimplifiedKnownStages(
         data_transfer_object=compressor_model_dto,
+        fluid_factory=fluid_factory,
     )
 
 
@@ -81,24 +96,48 @@ def _create_compressor_with_turbine(
 def _create_single_speed_compressor_train(
     compressor_model_dto: SingleSpeedCompressorTrain,
 ) -> SingleSpeedCompressorTrainCommonShaft:
+    fluid_factory = _create_fluid_factory(compressor_model_dto.fluid_model)
+    if fluid_factory is None:
+        raise ValueError("Fluid model is required for compressor train")
     return SingleSpeedCompressorTrainCommonShaft(
         data_transfer_object=compressor_model_dto,
+        fluid_factory=fluid_factory,
     )
 
 
 def _create_variable_speed_compressor_train(
     compressor_model_dto: VariableSpeedCompressorTrain,
 ) -> VariableSpeedCompressorTrainCommonShaft:
+    fluid_factory = _create_fluid_factory(compressor_model_dto.fluid_model)
+    if fluid_factory is None:
+        raise ValueError("Fluid model is required for compressor train")
     return VariableSpeedCompressorTrainCommonShaft(
         data_transfer_object=compressor_model_dto,
+        fluid_factory=fluid_factory,
     )
 
 
 def _create_variable_speed_compressor_train_multiple_streams_and_pressures(
     compressor_model_dto: VariableSpeedCompressorTrainMultipleStreamsAndPressures,
 ) -> VariableSpeedCompressorTrainCommonShaftMultipleStreamsAndPressures:
+    # Find the first inlet stream's fluid model for the train inlet
+    fluid_model_train_inlet = None
+    for stream in compressor_model_dto.streams:
+        if stream.typ == FluidStreamType.INGOING and stream.fluid_model is not None:
+            fluid_model_train_inlet = stream.fluid_model
+            break
+
+    # Fall back to dto fluid_model if no inlet stream has a fluid model
+    if fluid_model_train_inlet is None:
+        fluid_model_train_inlet = compressor_model_dto.fluid_model
+
+    fluid_factory_train_inlet = _create_fluid_factory(fluid_model_train_inlet)
+    if fluid_factory_train_inlet is None:
+        raise ValueError("Fluid model is required for compressor train")
+
     return VariableSpeedCompressorTrainCommonShaftMultipleStreamsAndPressures(
         data_transfer_object=compressor_model_dto,
+        fluid_factory=fluid_factory_train_inlet,
         streams=[
             _create_variable_speed_compressor_train_multiple_streams_and_pressures_stream(
                 stream_specification_dto, compressor_model_dto.stream_references
@@ -111,7 +150,13 @@ def _create_variable_speed_compressor_train_multiple_streams_and_pressures(
 def _create_compressor_train_simplified_with_unknown_stages(
     compressor_model_dto: CompressorTrainSimplifiedWithUnknownStages,
 ) -> CompressorTrainSimplifiedUnknownStages:
-    return CompressorTrainSimplifiedUnknownStages(data_transfer_object=compressor_model_dto)
+    fluid_factory = _create_fluid_factory(compressor_model_dto.fluid_model)
+    if fluid_factory is None:
+        raise ValueError("Fluid model is required for compressor train")
+    return CompressorTrainSimplifiedUnknownStages(
+        data_transfer_object=compressor_model_dto,
+        fluid_factory=fluid_factory,
+    )
 
 
 def _create_compressor_sampled(compressor_model_dto: CompressorSampled) -> CompressorModelSampled: