diff --git a/flow360/component/simulation/entity_info.py b/flow360/component/simulation/entity_info.py
index fc003c661..c5f236535 100644
--- a/flow360/component/simulation/entity_info.py
+++ b/flow360/component/simulation/entity_info.py
@@ -119,20 +119,27 @@ def _get_list_of_entities(
             entity_attribute_names = self.edge_attribute_names
             entity_full_list = self.grouped_edges
 
+        # Use the supplied one if not None
         if attribute_name is not None:
-            # pylint: disable=unsupported-membership-test,unsubscriptable-object
-            if attribute_name in entity_attribute_names:
-                # pylint: disable=no-member
-                return entity_full_list[entity_attribute_names.index(attribute_name)]
-            raise ValueError(
-                f"The given attribute_name {attribute_name} is not found"
-                f" in geometry metadata. Available: {entity_attribute_names}"
+            specified_attribute_name = attribute_name
+        else:
+            specified_attribute_name = (
+                self.face_group_tag if entity_type_name == "face" else self.edge_group_tag
             )
-        raise ValueError("Attribute name is required to get the full list of grouped entities.")
+
+            # pylint: disable=unsupported-membership-test,unsubscriptable-object
+        if specified_attribute_name in entity_attribute_names:
+            # pylint: disable=no-member
+            return entity_full_list[entity_attribute_names.index(specified_attribute_name)]
+        raise ValueError(
+            f"The given attribute_name {attribute_name} is not found"
+            f" in geometry metadata. Available: {entity_attribute_names}"
+        )
 
     def get_boundaries(self, attribute_name: str = None) -> list:
         """
-        Get the full list of boundary names. If it is geometry then use supplied attribute name to get the list.
+        Get the full list of boundaries.
+        If attribute_name is supplied then ignore stored face_group_tag and use supplied one.
         """
         return self._get_list_of_entities(attribute_name, "face")
 
@@ -144,12 +151,24 @@ class VolumeMeshEntityInfo(EntityInfoModel):
     zones: list[GenericVolume] = pd.Field([])
     boundaries: list[Surface] = pd.Field([])
 
+    @pd.field_validator("boundaries", mode="after")
+    @classmethod
+    def check_all_surface_has_interface_indicator(cls, value):
+        """private_attribute_is_interface should have been set comming from volume mesh."""
+        for item in value:
+            if item.private_attribute_is_interface is None:
+                raise ValueError(
+                    "[INTERNAL] {item.name} is missing private_attribute_is_interface attribute!."
+                )
+        return value
+
     # pylint: disable=arguments-differ
     def get_boundaries(self) -> list:
         """
         Get the full list of boundary names. If it is geometry then use supplied attribute name to get the list.
         """
-        return self.boundaries
+        # pylint: disable=not-an-iterable
+        return [item for item in self.boundaries if item.private_attribute_is_interface is False]
 
 
 class SurfaceMeshEntityInfo(EntityInfoModel):
diff --git a/flow360/component/simulation/framework/base_model.py b/flow360/component/simulation/framework/base_model.py
index f869fe6ef..b5caca4ac 100644
--- a/flow360/component/simulation/framework/base_model.py
+++ b/flow360/component/simulation/framework/base_model.py
@@ -163,6 +163,7 @@ def one_of(cls, values):
     # pylint: disable=no-self-argument
     # pylint: disable=duplicate-code
     @pd.model_validator(mode="before")
+    @classmethod
     def handle_conflicting_fields(cls, values):
         """
         root validator to handle deprecated aliases and fields
diff --git a/flow360/component/simulation/framework/param_utils.py b/flow360/component/simulation/framework/param_utils.py
index 1979b7e2a..4c6a86fa3 100644
--- a/flow360/component/simulation/framework/param_utils.py
+++ b/flow360/component/simulation/framework/param_utils.py
@@ -32,6 +32,15 @@ class AssetCache(Flow360BaseModel):
         Union[GeometryEntityInfo, VolumeMeshEntityInfo, SurfaceMeshEntityInfo]
     ] = pd.Field(None, frozen=True, discriminator="type_name")
 
+    @property
+    def boundaries(self):
+        """
+        Get all boundaries from the cached entity info.
+        """
+        if self.project_entity_info is None:
+            return None
+        return self.project_entity_info.get_boundaries()
+
 
 def register_entity_list(model: Flow360BaseModel, registry: EntityRegistry) -> None:
     """
diff --git a/flow360/component/simulation/operating_condition/operating_condition.py b/flow360/component/simulation/operating_condition/operating_condition.py
index 0336b9a60..3e66050de 100644
--- a/flow360/component/simulation/operating_condition/operating_condition.py
+++ b/flow360/component/simulation/operating_condition/operating_condition.py
@@ -311,11 +311,15 @@ def from_mach(
             reference_velocity_magnitude=reference_velocity_magnitude,
         )
 
-    @context_validator(context=CASE)
     @pd.model_validator(mode="after")
+    @context_validator(context=CASE)
     def check_valid_reference_velocity(self) -> Self:
         """Ensure reference velocity is provided when freestream velocity is 0."""
-        if self.velocity_magnitude.value == 0 and self.reference_velocity_magnitude is None:
+        if (
+            self.velocity_magnitude is not None
+            and self.velocity_magnitude.value == 0
+            and self.reference_velocity_magnitude is None
+        ):
             raise ValueError(
                 "Reference velocity magnitude/Mach must be provided when freestream velocity magnitude/Mach is 0."
             )
diff --git a/flow360/component/simulation/simulation_params.py b/flow360/component/simulation/simulation_params.py
index e81014217..033f1c375 100644
--- a/flow360/component/simulation/simulation_params.py
+++ b/flow360/component/simulation/simulation_params.py
@@ -62,6 +62,7 @@
 )
 from flow360.component.simulation.validation.validation_simulation_params import (
     _check_cht_solver_settings,
+    _check_complete_boundary_condition_and_unknown_surface,
     _check_consistency_ddes_volume_output,
     _check_consistency_wall_function_and_surface_output,
     _check_duplicate_entities_in_models,
@@ -76,7 +77,13 @@
 from flow360.exceptions import Flow360ConfigurationError, Flow360RuntimeError
 from flow360.version import __version__
 
-from .validation.validation_context import SURFACE_MESH, CaseField, ContextField
+from .validation.validation_context import (
+    CASE,
+    SURFACE_MESH,
+    CaseField,
+    ContextField,
+    context_validator,
+)
 
 ModelTypes = Annotated[Union[VolumeModelTypes, SurfaceModelTypes], pd.Field(discriminator="type")]
 
@@ -162,6 +169,7 @@ def copy(self, update=None, **kwargs) -> _ParamModelBase:
         return super().copy(update=update, **kwargs)
 
 
+# pylint: disable=too-many-public-methods
 class SimulationParams(_ParamModelBase):
     """All-in-one class for surface meshing + volume meshing + case configurations"""
 
@@ -273,16 +281,14 @@ def check_cht_solver_settings(self):
         return _check_cht_solver_settings(self)
 
     @pd.model_validator(mode="after")
-    @classmethod
-    def check_consistency_wall_function_and_surface_output(cls, v):
+    def check_consistency_wall_function_and_surface_output(self):
         """Only allow wallFunctionMetric output field when there is a Wall model with a wall function enabled"""
-        return _check_consistency_wall_function_and_surface_output(v)
+        return _check_consistency_wall_function_and_surface_output(self)
 
     @pd.model_validator(mode="after")
-    @classmethod
-    def check_consistency_ddes_volume_output(cls, v):
+    def check_consistency_ddes_volume_output(self):
         """Only allow DDES output field when there is a corresponding solver with DDES enabled in models"""
-        return _check_consistency_ddes_volume_output(v)
+        return _check_consistency_ddes_volume_output(self)
 
     @pd.model_validator(mode="after")
     def check_duplicate_entities_in_models(self):
@@ -290,16 +296,20 @@ def check_duplicate_entities_in_models(self):
         return _check_duplicate_entities_in_models(self)
 
     @pd.model_validator(mode="after")
-    @classmethod
-    def check_numerical_dissipation_factor_output(cls, v):
+    def check_numerical_dissipation_factor_output(self):
         """Only allow numericalDissipationFactor output field when the NS solver has low numerical dissipation"""
-        return _check_numerical_dissipation_factor_output(v)
+        return _check_numerical_dissipation_factor_output(self)
 
     @pd.model_validator(mode="after")
-    @classmethod
-    def check_low_mach_preconditioner_output(cls, v):
+    def check_low_mach_preconditioner_output(self):
         """Only allow lowMachPreconditioner output field when the lowMachPreconditioner is enabled in the NS solver"""
-        return _check_low_mach_preconditioner_output(v)
+        return _check_low_mach_preconditioner_output(self)
+
+    @pd.model_validator(mode="after")
+    @context_validator(context=CASE)
+    def check_complete_boundary_condition_and_unknown_surface(self):
+        """Make sure that all boundaries have been assigned with a boundary condition"""
+        return _check_complete_boundary_condition_and_unknown_surface(self)
 
     @pd.model_validator(mode="after")
     def check_output_fields(params):
diff --git a/flow360/component/simulation/translator/surface_meshing_translator.py b/flow360/component/simulation/translator/surface_meshing_translator.py
index 927b4ef7f..41b0b4d6d 100644
--- a/flow360/component/simulation/translator/surface_meshing_translator.py
+++ b/flow360/component/simulation/translator/surface_meshing_translator.py
@@ -127,11 +127,8 @@ def get_surface_meshing_json(input_params: SimulationParams, mesh_units):
 
     ##:: >> Step 6: Tell surface mesher how do we group boundaries.
     translated["boundaries"] = {}
-    face_group_tag = input_params.private_attribute_asset_cache.project_entity_info.face_group_tag
     grouped_faces: List[Surface] = (
-        input_params.private_attribute_asset_cache.project_entity_info.get_boundaries(
-            face_group_tag
-        )
+        input_params.private_attribute_asset_cache.project_entity_info.get_boundaries()
     )
     for surface in grouped_faces:
         for face_id in surface.private_attribute_sub_components:
diff --git a/flow360/component/simulation/validation/validation_simulation_params.py b/flow360/component/simulation/validation/validation_simulation_params.py
index d0675fb8b..7798527e9 100644
--- a/flow360/component/simulation/validation/validation_simulation_params.py
+++ b/flow360/component/simulation/validation/validation_simulation_params.py
@@ -2,8 +2,10 @@
 validation for SimulationParams
 """
 
+from typing import get_args
+
 from flow360.component.simulation.models.solver_numerics import NoneSolver
-from flow360.component.simulation.models.surface_models import Wall
+from flow360.component.simulation.models.surface_models import SurfaceModelTypes, Wall
 from flow360.component.simulation.models.volume_models import (
     Fluid,
     NavierStokesInitialCondition,
@@ -18,6 +20,7 @@
     VolumeOutput,
 )
 from flow360.component.simulation.primitives import (
+    GhostSurface,
     _SurfaceEntityBase,
     _VolumeEntityBase,
 )
@@ -272,6 +275,65 @@ def _validate_cht_has_heat_transfer(params):
     return params
 
 
+def _check_complete_boundary_condition_and_unknown_surface(params):
+    ## Step 1: Get all boundaries patches from asset cache
+
+    current_lvls = get_validation_levels() if get_validation_levels() else []
+    if all(level not in current_lvls for level in (ALL, CASE)):
+        return params
+
+    asset_boundary_entities = params.private_attribute_asset_cache.boundaries
+
+    if asset_boundary_entities is None or asset_boundary_entities == []:
+        raise ValueError("[Internal] Failed to retrieve asset boundaries")
+
+    asset_boundaries = {boundary.name for boundary in asset_boundary_entities}
+
+    ## Step 2: Collect all used boundaries from the models
+    if len(params.models) == 1 and isinstance(params.models[0], Fluid):
+        raise ValueError("No boundary conditions are defined in the `models` section.")
+
+    used_boundaries = set()
+
+    for model in params.models:
+        if not isinstance(model, get_args(SurfaceModelTypes)):
+            continue
+
+        entities = []
+        # pylint: disable=protected-access
+        if hasattr(model, "entities"):
+            entities = model.entities._get_expanded_entities(create_hard_copy=False)
+        elif hasattr(model, "entity_pairs"):  # Periodic BC
+            entities = [
+                pair for surface_pair in model.entity_pairs.items for pair in surface_pair.pair
+            ]
+
+        for entity in entities:
+            if isinstance(entity, GhostSurface):
+                continue
+            used_boundaries.add(entity.name)
+
+    ## Step 3: Use set operations to find missing and unknown boundaries
+    missing_boundaries = asset_boundaries - used_boundaries
+    unknown_boundaries = used_boundaries - asset_boundaries
+
+    if missing_boundaries:
+        missing_list = ", ".join(sorted(missing_boundaries))
+        raise ValueError(
+            f"The following boundaries do not have a boundary condition: {missing_list}. "
+            "Please add them to a boundary condition model in the `models` section."
+        )
+
+    if unknown_boundaries:
+        unknown_list = ", ".join(sorted(unknown_boundaries))
+        raise ValueError(
+            f"The following boundaries are not known `Surface` "
+            f"entities but appear in the `models` section: {unknown_list}."
+        )
+
+    return params
+
+
 def _check_parent_volume_is_rotating(models):
 
     current_lvls = get_validation_levels() if get_validation_levels() else []
diff --git a/tests/ref/simulation/simulation_json_with_multi_constructor_used.json b/tests/ref/simulation/simulation_json_with_multi_constructor_used.json
index 3cfc12768..7e83541f9 100644
--- a/tests/ref/simulation/simulation_json_with_multi_constructor_used.json
+++ b/tests/ref/simulation/simulation_json_with_multi_constructor_used.json
@@ -186,6 +186,25 @@
         ]
     },
     "models": [
+        {
+            "type": "Wall",
+            "entities": {
+                "stored_entities": [
+                    {
+                        "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                        "private_attribute_entity_type_name": "Surface",
+                        "name": "surface_x",
+                        "private_attribute_is_interface": false,
+                        "private_attribute_sub_components": [
+                            "face_x_1",
+                            "face_x_2",
+                            "face_x_3"
+                        ]
+                    }
+                ]
+            },
+            "use_wall_function": false
+        },
         {
             "material": {
                 "dynamic_viscosity": {
@@ -371,5 +390,35 @@
     "unit_system": {
         "name": "SI"
     },
-    "version": "24.2.0"
-}
+    "version": "24.2.0",
+    "private_attribute_asset_cache": {
+        "project_length_unit": "m",
+        "project_entity_info": {
+            "type_name": "GeometryEntityInfo",
+            "face_ids": [
+                "face_x_1",
+                "face_x_2",
+                "face_x_3"
+            ],
+            "face_group_tag": "some_tag",
+            "face_attribute_names": [
+                "some_tag"
+            ],
+            "grouped_faces": [
+                [
+                    {
+                        "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                        "private_attribute_entity_type_name": "Surface",
+                        "name": "surface_x",
+                        "private_attribute_is_interface": false,
+                        "private_attribute_sub_components": [
+                            "face_x_1",
+                            "face_x_2",
+                            "face_x_3"
+                        ]
+                    }
+                ]
+            ]
+        }
+    }
+}
\ No newline at end of file
diff --git a/tests/simulation/params/test_validators_params.py b/tests/simulation/params/test_validators_params.py
index d63b11c71..c8b52820b 100644
--- a/tests/simulation/params/test_validators_params.py
+++ b/tests/simulation/params/test_validators_params.py
@@ -1,11 +1,22 @@
+import json
 import re
 import unittest
+from typing import Literal
 
 import pytest
 
 import flow360.component.simulation.units as u
+from flow360.component.simulation.entity_info import VolumeMeshEntityInfo
+from flow360.component.simulation.framework.param_utils import AssetCache
+from flow360.component.simulation.meshing_param.volume_params import AutomatedFarfield
 from flow360.component.simulation.models.material import SolidMaterial, aluminum
-from flow360.component.simulation.models.surface_models import SlipWall, Wall
+from flow360.component.simulation.models.surface_models import (
+    Freestream,
+    Periodic,
+    SlipWall,
+    Translational,
+    Wall,
+)
 from flow360.component.simulation.models.volume_models import (
     AngleExpression,
     Fluid,
@@ -14,6 +25,9 @@
     Rotation,
     Solid,
 )
+from flow360.component.simulation.operating_condition.operating_condition import (
+    AerospaceCondition,
+)
 from flow360.component.simulation.outputs.output_entities import Point, Slice
 from flow360.component.simulation.outputs.outputs import (
     ProbeOutput,
@@ -28,7 +42,10 @@
 from flow360.component.simulation.time_stepping.time_stepping import Steady, Unsteady
 from flow360.component.simulation.unit_system import SI_unit_system
 from flow360.component.simulation.validation.validation_context import (
+    ALL,
     CASE,
+    SURFACE_MESH,
+    VOLUME_MESH,
     ValidationLevelContext,
 )
 
@@ -307,6 +324,75 @@ def test_cht_solver_settings_validator(
         )
 
 
+def test_incomplete_BC():
+    ##:: Construct a dummy asset cache
+
+    wall_1 = Surface(
+        name="wall_1", private_attribute_is_interface=False, private_attribute_tag_key="test"
+    )
+    periodic_1 = Surface(
+        name="periodic_1", private_attribute_is_interface=False, private_attribute_tag_key="test"
+    )
+    periodic_2 = Surface(
+        name="periodic_2", private_attribute_is_interface=False, private_attribute_tag_key="test"
+    )
+    i_exist = Surface(
+        name="i_exist", private_attribute_is_interface=False, private_attribute_tag_key="test"
+    )
+    no_bc = Surface(
+        name="no_bc", private_attribute_is_interface=False, private_attribute_tag_key="test"
+    )
+    some_interface = Surface(
+        name="some_interface", private_attribute_is_interface=True, private_attribute_tag_key="test"
+    )
+
+    asset_cache = AssetCache(
+        project_length_unit="inch",
+        project_entity_info=VolumeMeshEntityInfo(
+            boundaries=[wall_1, periodic_1, periodic_2, i_exist, some_interface, no_bc]
+        ),
+    )
+    auto_farfield = AutomatedFarfield(name="my_farfield")
+
+    with pytest.raises(
+        ValueError,
+        match=re.escape(
+            r"The following boundaries do not have a boundary condition: no_bc. Please add them to a boundary condition model in the `models` section."
+        ),
+    ):
+        with ValidationLevelContext(ALL):
+            with SI_unit_system:
+                SimulationParams(
+                    models=[
+                        Fluid(),
+                        Wall(entities=wall_1),
+                        Periodic(surface_pairs=(periodic_1, periodic_2), spec=Translational()),
+                        SlipWall(entities=[i_exist]),
+                        Freestream(entities=auto_farfield.farfield),
+                    ],
+                    private_attribute_asset_cache=asset_cache,
+                )
+    with pytest.raises(
+        ValueError,
+        match=re.escape(
+            r"The following boundaries are not known `Surface` entities but appear in the `models` section: plz_dont_do_this."
+        ),
+    ):
+        with ValidationLevelContext(ALL):
+            with SI_unit_system:
+                SimulationParams(
+                    models=[
+                        Fluid(),
+                        Wall(entities=[wall_1]),
+                        Periodic(surface_pairs=(periodic_1, periodic_2), spec=Translational()),
+                        SlipWall(entities=[i_exist]),
+                        Freestream(entities=auto_farfield.farfield),
+                        SlipWall(entities=[Surface(name="plz_dont_do_this"), no_bc]),
+                    ],
+                    private_attribute_asset_cache=asset_cache,
+                )
+
+
 def test_duplicate_entities_in_models():
     entity_generic_volume = GenericVolume(name="Duplicate Volume")
     entity_surface = Surface(name="Duplicate Surface")
@@ -340,6 +426,17 @@ def test_duplicate_entities_in_models():
         )
 
 
+def test_valid_reference_velocity():
+    with pytest.raises(
+        ValueError,
+        match=re.escape(
+            "Reference velocity magnitude/Mach must be provided when freestream velocity magnitude/Mach is 0."
+        ),
+    ):
+        with SI_unit_system:
+            SimulationParams(operating_condition=AerospaceCondition(velocity_magnitude=0))
+
+
 def test_output_fields_with_user_defined_fields():
     surface_1 = Surface(name="some_random_surface")
     # 1: No user defined fields
@@ -444,6 +541,8 @@ def test_rotation_parent_volumes():
         axis=(0, 1, 2),
     )
 
+    my_wall = Surface(name="my_wall", private_attribute_is_interface=False)
+
     msg = "For model #1, the parent rotating volume (stationary_cylinder) is not "
     "used in any other `Rotation` model's `volumes`."
     with pytest.raises(ValueError, match=re.escape(msg)):
@@ -463,5 +562,10 @@ def test_rotation_parent_volumes():
                     Fluid(),
                     Rotation(entities=[c_1], spec=AngleExpression("1+2"), parent_volume=c_2),
                     Rotation(entities=[c_2], spec=AngleExpression("1+5")),
-                ]
+                    Wall(entities=[my_wall]),
+                ],
+                private_attribute_asset_cache=AssetCache(
+                    project_length_unit="cm",
+                    project_entity_info=VolumeMeshEntityInfo(boundaries=[my_wall]),
+                ),
             )
diff --git a/tests/simulation/service/test_services_v2.py b/tests/simulation/service/test_services_v2.py
index 0d73c84df..586052566 100644
--- a/tests/simulation/service/test_services_v2.py
+++ b/tests/simulation/service/test_services_v2.py
@@ -4,8 +4,9 @@
 import pytest
 
 from flow360.component.simulation import services
-from flow360.component.simulation.simulation_params import SimulationParams
-from flow360.component.simulation.unit_system import SI_unit_system
+from flow360.component.simulation.entity_info import VolumeMeshEntityInfo
+from flow360.component.simulation.framework.param_utils import AssetCache
+from flow360.component.simulation.primitives import Surface
 from flow360.component.simulation.validation.validation_context import (
     SURFACE_MESH,
     VOLUME_MESH,
@@ -51,7 +52,43 @@ def test_validate_service():
             "max_steps": 10,
             "CFL": {"type": "ramp", "initial": 1.5, "final": 1.5, "ramp_steps": 5},
         },
+        "models": [
+            {
+                "type": "Wall",
+                "entities": {
+                    "stored_entities": [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "Mysurface",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [],
+                        }
+                    ]
+                },
+                "use_wall_function": False,
+            }
+        ],
         "user_defined_dynamics": [],
+        "private_attribute_asset_cache": {
+            "project_length_unit": None,
+            "project_entity_info": {
+                "draft_entities": [],
+                "type_name": "VolumeMeshEntityInfo",
+                "zones": [],
+                "boundaries": [
+                    {
+                        "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                        "private_attribute_entity_type_name": "Surface",
+                        "name": "Mysurface",
+                        "private_attribute_full_name": None,
+                        "private_attribute_is_interface": False,
+                        "private_attribute_tag_key": None,
+                        "private_attribute_sub_components": [],
+                    }
+                ],
+            },
+        },
     }
 
     params_data_from_geo = params_data_from_vm
@@ -429,6 +466,51 @@ def test_front_end_JSON_with_multi_constructor():
         },
         "unit_system": {"name": "SI"},
         "version": "24.2.0",
+        "private_attribute_asset_cache": {
+            "project_length_unit": "m",
+            "project_entity_info": {
+                "type_name": "GeometryEntityInfo",
+                "face_ids": ["face_x_1", "face_x_2", "face_x_3"],
+                "face_group_tag": "some_tag",
+                "face_attribute_names": ["some_tag"],
+                "grouped_faces": [
+                    [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "surface_x",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                                "face_x_2",
+                                "face_x_3",
+                            ],
+                        }
+                    ]
+                ],
+            },
+        },
+        "models": [
+            {
+                "type": "Wall",
+                "entities": {
+                    "stored_entities": [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "surface_x",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                                "face_x_2",
+                                "face_x_3",
+                            ],
+                        }
+                    ]
+                },
+                "use_wall_function": False,
+            }
+        ],
         "operating_condition": {
             "type_name": "AerospaceCondition",
             "private_attribute_constructor": "from_mach",
@@ -494,13 +576,49 @@ def test_generate_process_json():
             "beta": {"value": 0.0, "units": "degree"},
             # "velocity_magnitude": {"value": 0.8, "units": "km/s"},
         },
+        "models": [
+            {
+                "type": "Wall",
+                "entities": {
+                    "stored_entities": [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "surface_x",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                                "face_x_2",
+                                "face_x_3",
+                            ],
+                        }
+                    ]
+                },
+                "use_wall_function": False,
+            }
+        ],
         "private_attribute_asset_cache": {
             "project_length_unit": "m",
             "project_entity_info": {
                 "type_name": "GeometryEntityInfo",
-                "face_ids": ["face_x"],
-                "face_group_tag": "not_used",
-                "face_attribute_names": ["not_used"],
+                "face_ids": ["face_x_1", "face_x_2", "face_x_3"],
+                "face_group_tag": "some_tag",
+                "face_attribute_names": ["some_tag"],
+                "grouped_faces": [
+                    [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "surface_x",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                                "face_x_2",
+                                "face_x_3",
+                            ],
+                        }
+                    ]
+                ],
             },
         },
     }
diff --git a/tests/simulation/service/test_translator_service.py b/tests/simulation/service/test_translator_service.py
index df0aa2439..f553422c8 100644
--- a/tests/simulation/service/test_translator_service.py
+++ b/tests/simulation/service/test_translator_service.py
@@ -397,6 +397,46 @@ def test_simulation_to_case_json():
         ],
         "unit_system": {"name": "SI"},
         "version": "24.2.0",
+        "private_attribute_asset_cache": {
+            "project_length_unit": "m",
+            "project_entity_info": {
+                "type_name": "GeometryEntityInfo",
+                "face_ids": ["face_x_1", "face_x_2", "face_x_3"],
+                "face_group_tag": "some_tag",
+                "face_attribute_names": ["some_tag"],
+                "grouped_faces": [
+                    [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "1",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                            ],
+                        },
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "3",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_3",
+                            ],
+                        },
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "2",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_2",
+                            ],
+                        },
+                    ]
+                ],
+            },
+        },
     }
 
     params, _, _ = validate_model(param_data, "SI", "Geometry")
@@ -461,6 +501,42 @@ def test_simulation_to_case_vm_workflow():
         },
         "unit_system": {"name": "SI"},
         "version": "24.2.0",
+        "models": [
+            {
+                "type": "Wall",
+                "entities": {
+                    "stored_entities": [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "Mysurface",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [],
+                        }
+                    ]
+                },
+                "use_wall_function": False,
+            }
+        ],
+        "private_attribute_asset_cache": {
+            "project_length_unit": None,
+            "project_entity_info": {
+                "draft_entities": [],
+                "type_name": "VolumeMeshEntityInfo",
+                "zones": [],
+                "boundaries": [
+                    {
+                        "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                        "private_attribute_entity_type_name": "Surface",
+                        "name": "Mysurface",
+                        "private_attribute_full_name": None,
+                        "private_attribute_is_interface": False,
+                        "private_attribute_tag_key": None,
+                        "private_attribute_sub_components": [],
+                    }
+                ],
+            },
+        },
     }
 
     params, _, _ = validate_model(param_data, "SI", "Geometry")
@@ -469,7 +545,7 @@ def test_simulation_to_case_vm_workflow():
         case_json, hash = simulation_to_case_json(params, {"value": 100.0, "units": "cm"})
         print(case_json)
 
-    params, _, _ = validate_model(param_data, "SI", "VolumeMesh")
+    params, errors, _ = validate_model(param_data, "SI", "VolumeMesh")
     case_json, hash = simulation_to_case_json(params, {"value": 100.0, "units": "cm"})
     print(case_json)
 
@@ -510,14 +586,50 @@ def test_simulation_to_all_translation_2():
             "moment_length": {"value": 1, "units": "m"},
             "area": {"value": 1, "units": "m**2"},
         },
-        "models": [],
+        "models": [
+            {
+                "type": "Wall",
+                "entities": {
+                    "stored_entities": [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "surface_x",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                                "face_x_2",
+                                "face_x_3",
+                            ],
+                        }
+                    ]
+                },
+                "use_wall_function": False,
+            }
+        ],
         "private_attribute_asset_cache": {
+            "project_length_unit": "m",
             "project_entity_info": {
                 "type_name": "GeometryEntityInfo",
-                "face_ids": ["face_x"],
-                "face_group_tag": "not_used",
-                "face_attribute_names": ["not_used"],
-            }
+                "face_ids": ["face_x_1", "face_x_2", "face_x_3"],
+                "face_group_tag": "some_tag",
+                "face_attribute_names": ["some_tag"],
+                "grouped_faces": [
+                    [
+                        {
+                            "private_attribute_registry_bucket_name": "SurfaceEntityType",
+                            "private_attribute_entity_type_name": "Surface",
+                            "name": "surface_x",
+                            "private_attribute_is_interface": False,
+                            "private_attribute_sub_components": [
+                                "face_x_1",
+                                "face_x_2",
+                                "face_x_3",
+                            ],
+                        }
+                    ]
+                ],
+            },
         },
     }