PythonModels/components/amesim_pneumatic_line.py

@@ -0,0 +1,284 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from math import log10, pi
+
+from PythonModels.components.amesim_pneumatic import (
+    HELIUM_PNEUMATIC_GAS,
+    AmesimPneumaticGas,
+    diameter_mm_to_area_m2,
+)
+from PythonModels.core.base import DynamicComponent
+from PythonModels.core.medium import ThermodynamicProperties
+from PythonModels.core.ports import PortState
+from PythonModels.core.state import VolumeState
+
+
+@dataclass(frozen=True)
+class AmesimPnl0001Diagnostics:
+    mass_flow_kg_s: float
+    reynolds_number: float
+    gas_velocity_m_s: float
+    friction_factor: float
+    pressure_drop_pa: float
+
+
+class AmesimPnl0001Pipe(DynamicComponent):
+    """Physical first-pass implementation of AMESim ``PNL0001`` (C-R).
+
+    Port 2 owns the lumped gas storage. Port 1 is connected through a Darcy
+    resistance. Both connection mass flows use the PythonModels convention:
+    positive values enter the pipe storage.
+
+    AMESim's proprietary pressure-loss calibration is not available in the
+    archive. This implementation therefore uses an explicit Darcy-Weisbach
+    law while preserving the real geometry, state count, mass/energy balance,
+    heat-transfer parameter, and observable diagnostics.
+    """
+
+    def __init__(
+        self,
+        name: str,
+        *,
+        diameter_mm: float,
+        length_m: float,
+        relative_roughness: float,
+        polytropic_constant: float = 1.35,
+        heat_transfer_coefficient: float = 0.0,
+        external_temperature_k: float = 293.15,
+        gas: AmesimPneumaticGas = HELIUM_PNEUMATIC_GAS,
+        p0: float = 101_325.0,
+        T0: float = 293.15,
+    ) -> None:
+        if diameter_mm <= 0.0:
+            raise ValueError("diameter_mm must be positive")
+        if length_m <= 0.0:
+            raise ValueError("length_m must be positive")
+        if relative_roughness < 0.0:
+            raise ValueError("relative_roughness must be non-negative")
+        if polytropic_constant <= 0.0:
+            raise ValueError("polytropic_constant must be positive")
+        if heat_transfer_coefficient < 0.0:
+            raise ValueError("heat_transfer_coefficient must be non-negative")
+        if external_temperature_k <= 0.0:
+            raise ValueError("external_temperature_k must be positive")
+
+        super().__init__(name=name)
+        self.diameter = diameter_mm * 1.0e-3
+        self.length = length_m
+        self.relative_roughness = relative_roughness
+        self.polytropic_constant = polytropic_constant
+        self.heat_transfer_coefficient = heat_transfer_coefficient
+        self.external_temperature = external_temperature_k
+        self.gas = gas
+        self.area = diameter_mm_to_area_m2(diameter_mm)
+        self.volume = self.area * self.length
+        self.heat_transfer_area = pi * self.diameter * self.length
+
+        rho0 = gas.density(p0, T0)
+        mass0 = rho0 * self.volume
+        self.state = VolumeState(
+            m=mass0,
+            U=mass0 * gas.specific_internal_energy(T0),
+        )
+        self.port_1 = PortState()
+        self.port_2 = PortState()
+
+    def get_state_vector(self) -> list[float]:
+        return self.state.as_vector()
+
+    def set_state_vector(self, values: list[float]) -> None:
+        self.state = VolumeState.from_vector(values)
+
+    def properties(self) -> ThermodynamicProperties:
+        if self.state.m <= 0.0:
+            raise ValueError("pipe mass must stay positive")
+        temperature = self.gas.temperature_from_internal_energy(
+            self.state.U / self.state.m
+        )
+        density = self.state.m / self.volume
+        pressure = self.gas.pressure(density, temperature)
+        properties = ThermodynamicProperties(
+            p=pressure,
+            T=temperature,
+            rho=density,
+            u=self.state.U / self.state.m,
+            h=self.gas.specific_enthalpy(temperature),
+        )
+        self.port_2.p = pressure
+        self.port_2.h_outflow = properties.h
+        return properties
+
+    def gas_mass_g(self) -> float:
+        return self.state.m * 1.0e3
+
+    def resistance_mass_flow(
+        self,
+        *,
+        port_1_pressure_pa: float,
+        port_1_temperature_k: float,
+    ) -> float:
+        """Return mass flow from port 1 into the port-2 storage in kg/s."""
+        if port_1_pressure_pa <= 0.0:
+            raise ValueError("port_1_pressure_pa must be positive")
+        if port_1_temperature_k <= 0.0:
+            raise ValueError("port_1_temperature_k must be positive")
+
+        internal = self.properties()
+        pressure_difference = port_1_pressure_pa - internal.p
+        if pressure_difference == 0.0:
+            return 0.0
+        upstream_pressure = max(port_1_pressure_pa, internal.p)
+        upstream_temperature = (
+            port_1_temperature_k if pressure_difference > 0.0 else internal.T
+        )
+        density = self.gas.density(upstream_pressure, upstream_temperature)
+        magnitude = self._mass_flow_for_pressure_drop(
+            abs(pressure_difference),
+            density=density,
+            temperature=upstream_temperature,
+        )
+        return magnitude if pressure_difference > 0.0 else -magnitude
+
+    def diagnostics(
+        self,
+        *,
+        mass_flow_kg_s: float,
+        temperature_k: float | None = None,
+    ) -> AmesimPnl0001Diagnostics:
+        properties = self.properties()
+        temperature = temperature_k or properties.T
+        reynolds = self._reynolds_number(mass_flow_kg_s, temperature)
+        friction_factor = self._friction_factor(reynolds)
+        velocity = mass_flow_kg_s / (properties.rho * self.area)
+        pressure_drop = self._darcy_pressure_drop(
+            mass_flow_kg_s,
+            density=properties.rho,
+            temperature=temperature,
+        )
+        return AmesimPnl0001Diagnostics(
+            mass_flow_kg_s=mass_flow_kg_s,
+            reynolds_number=reynolds,
+            gas_velocity_m_s=velocity,
+            friction_factor=friction_factor,
+            pressure_drop_pa=pressure_drop,
+        )
+
+    def derivatives_from_connections(
+        self,
+        *,
+        port_1_m_flow: float,
+        connected_h_1: float,
+        port_2_m_flow: float,
+        connected_h_2: float,
+    ) -> VolumeState:
+        internal = self.properties()
+        inlet_h_1 = self.connection_inlet_enthalpy(
+            port_m_flow=port_1_m_flow,
+            connected_h=connected_h_1,
+            internal_h=internal.h,
+        )
+        inlet_h_2 = self.connection_inlet_enthalpy(
+            port_m_flow=port_2_m_flow,
+            connected_h=connected_h_2,
+            internal_h=internal.h,
+        )
+        heat_flow = (
+            self.heat_transfer_coefficient
+            * self.heat_transfer_area
+            * (self.external_temperature - internal.T)
+        )
+        return VolumeState(
+            m=port_1_m_flow + port_2_m_flow,
+            U=port_1_m_flow * inlet_h_1 + port_2_m_flow * inlet_h_2 + heat_flow,
+        )
+
+    def _mass_flow_for_pressure_drop(
+        self,
+        pressure_drop_pa: float,
+        *,
+        density: float,
+        temperature: float,
+    ) -> float:
+        if pressure_drop_pa <= 0.0:
+            return 0.0
+        upper = 1.0e-9
+        while self._darcy_pressure_drop(
+            upper,
+            density=density,
+            temperature=temperature,
+        ) < pressure_drop_pa:
+            upper *= 10.0
+            if upper > 1.0e3:
+                raise ValueError("unable to bracket PNL0001 resistance flow")
+        lower = 0.0
+        for _ in range(80):
+            middle = 0.5 * (lower + upper)
+            if self._darcy_pressure_drop(
+                middle,
+                density=density,
+                temperature=temperature,
+            ) < pressure_drop_pa:
+                lower = middle
+            else:
+                upper = middle
+        return 0.5 * (lower + upper)
+
+    def _darcy_pressure_drop(
+        self,
+        mass_flow_kg_s: float,
+        *,
+        density: float,
+        temperature: float,
+    ) -> float:
+        if mass_flow_kg_s == 0.0:
+            return 0.0
+        reynolds = self._reynolds_number(mass_flow_kg_s, temperature)
+        friction_factor = self._friction_factor(reynolds)
+        velocity = mass_flow_kg_s / (density * self.area)
+        magnitude = (
+            friction_factor
+            * (self.length / self.diameter)
+            * density
+            * velocity
+            * velocity
+            / 2.0
+        )
+        return magnitude if mass_flow_kg_s > 0.0 else -magnitude
+
+    def _reynolds_number(self, mass_flow_kg_s: float, temperature: float) -> float:
+        viscosity = helium_dynamic_viscosity(temperature)
+        return 4.0 * abs(mass_flow_kg_s) / (pi * self.diameter * viscosity)
+
+    def _friction_factor(self, reynolds_number: float) -> float:
+        if reynolds_number <= 0.0:
+            return 64_000_000.0
+        laminar = 64.0 / reynolds_number
+        if reynolds_number <= 2_300.0:
+            return laminar
+        turbulent = 1.0 / (
+            -1.8
+            * log10(
+                (self.relative_roughness / 3.7) ** 1.11
+                + 6.9 / reynolds_number
+            )
+        ) ** 2
+        if reynolds_number >= 4_000.0:
+            return turbulent
+        fraction = (reynolds_number - 2_300.0) / 1_700.0
+        return laminar + fraction * (turbulent - laminar)
+
+
+def helium_dynamic_viscosity(temperature_k: float) -> float:
+    """Sutherland approximation centered on the test_mql initial condition."""
+    if temperature_k <= 0.0:
+        raise ValueError("temperature_k must be positive")
+    reference_temperature = 293.15
+    reference_viscosity = 2.0e-5
+    sutherland_constant = 79.4
+    return (
+        reference_viscosity
+        * (temperature_k / reference_temperature) ** 1.5
+        * (reference_temperature + sutherland_constant)
+        / (temperature_k + sutherland_constant)
+    )

PythonModels/systems/test_mql.py

@@ -3859,6 +3859,7 @@ class TestMqlSystem:
     def __init__(self, archive_path: Path | None = None) -> None:
         self.archive_path = archive_path or Path(__file__).resolve().parents[2] / AMESIM_ARCHIVE_RELATIVE_PATH
         self.network = SimulationNetwork(name=MODEL_NAME)
+        self.pnl0001_assembly = self._build_pnl0001_assembly()
         self.pneumatic_assembly = self._build_pneumatic_assembly()
         pneumatic_components = self._pneumatic_components_by_alias()
         for spec in COMPONENT_SPECS:
@@ -3881,6 +3882,13 @@ class TestMqlSystem:
 
         return build_test_mql_pneumatic_assembly()
 
+    def _build_pnl0001_assembly(self):
+        from PythonModels.systems.test_mql_pneumatic_lines import (
+            build_test_mql_pnl0001_assembly,
+        )
+
+        return build_test_mql_pnl0001_assembly(self.archive_path)
+
     def _pneumatic_components_by_alias(self) -> dict[str, Component]:
         return {
             **self.pneumatic_assembly.fixed_chambers,
@@ -3893,6 +3901,10 @@ class TestMqlSystem:
     def typed_pneumatic_component_count(self) -> int:
         return len(self._pneumatic_components_by_alias())
 
+    @property
+    def typed_pnl0001_line_count(self) -> int:
+        return len(self.pnl0001_assembly.lines)
+
     def pneumatic_state_vector(self) -> list[float]:
         return self.network.initial_state_vector()
 
@@ -4071,6 +4083,84 @@ class TestMqlSystem:
             t_eval=t_eval,
         )
 
+    def pnl0001_chamber_segment_closure_from_spec(
+        self,
+        spec,
+        *,
+        inlet_node_pressure_pa: float,
+        outlet_pressure_pa: float,
+        inlet_node_temperature_k: float = 293.15,
+        outlet_temperature_k: float = 293.15,
+    ):
+        """Insert the topology-derived inlet PNL0001 into a chamber segment."""
+        from PythonModels.components.amesim_pneumatic import (
+            AmesimPneumaticOrifice,
+            AmesimPneumaticVolume,
+        )
+        from PythonModels.systems.test_mql_closure import (
+            TestMqlPneumaticBoundaryCondition,
+            TestMqlPnl0001ChamberSegmentClosure,
+            TestMqlPnl0001ChamberSegmentComponents,
+        )
+
+        inlet_line = self.pnl0001_assembly.lines[spec.inlet_line_alias]
+        volume = self.network.components[spec.volume_alias]
+        inlet_orifice = self.network.components[spec.inlet_orifice_alias]
+        outlet_orifice = self.network.components[spec.outlet_orifice_alias]
+        if not isinstance(volume, AmesimPneumaticVolume):
+            raise TypeError(f"{spec.volume_alias} is not an AMESim pneumatic volume")
+        if not isinstance(inlet_orifice, AmesimPneumaticOrifice):
+            raise TypeError(
+                f"{spec.inlet_orifice_alias} is not an AMESim pneumatic orifice"
+            )
+        if not isinstance(outlet_orifice, AmesimPneumaticOrifice):
+            raise TypeError(
+                f"{spec.outlet_orifice_alias} is not an AMESim pneumatic orifice"
+            )
+        return TestMqlPnl0001ChamberSegmentClosure(
+            components=TestMqlPnl0001ChamberSegmentComponents(
+                inlet_line=inlet_line,
+                volume=volume,
+                inlet_orifice=inlet_orifice,
+                outlet_orifice=outlet_orifice,
+                spec=spec,
+            ),
+            inlet_node=TestMqlPneumaticBoundaryCondition(
+                pressure_pa=inlet_node_pressure_pa,
+                temperature_k=inlet_node_temperature_k,
+            ),
+            outlet_boundary=TestMqlPneumaticBoundaryCondition(
+                pressure_pa=outlet_pressure_pa,
+                temperature_k=outlet_temperature_k,
+            ),
+        )
+
+    def simulate_pnl0001_chamber_segment_from_spec(
+        self,
+        spec,
+        *,
+        inlet_node_pressure_pa: float,
+        outlet_pressure_pa: float,
+        inlet_node_temperature_k: float = 293.15,
+        outlet_temperature_k: float = 293.15,
+        config: SolveIVPConfig | None = None,
+        t_eval: list[float] | None = None,
+    ):
+        closure = self.pnl0001_chamber_segment_closure_from_spec(
+            spec,
+            inlet_node_pressure_pa=inlet_node_pressure_pa,
+            outlet_pressure_pa=outlet_pressure_pa,
+            inlet_node_temperature_k=inlet_node_temperature_k,
+            outlet_temperature_k=outlet_temperature_k,
+        )
+        run_config = config or SolveIVPConfig(t_stop=1.0e-4, max_step=1.0e-5)
+        return integrate_ode(
+            rhs=lambda t, state: closure.rhs(state),
+            initial_state=closure.initial_state_vector(),
+            config=run_config,
+            t_eval=t_eval,
+        )
+
     def pneumatic_branch_closure_from_spec(self, spec):
         return self.pneumatic_branch_closure(
             name=spec.name,

PythonModels/systems/test_mql_closure.py

@@ -8,6 +8,7 @@ from PythonModels.components.amesim_pneumatic import (
     AmesimPneumaticOrifice,
     AmesimPneumaticVolume,
 )
+from PythonModels.components.amesim_pneumatic_line import AmesimPnl0001Pipe
 from PythonModels.core.medium import ThermodynamicProperties
 from PythonModels.core.ports import PortState
 from PythonModels.core.state import VolumeState
@@ -98,6 +99,26 @@ class TestMqlPneumaticChamberSegmentSnapshot:
     outlet_flow: float
 
 
+@dataclass(frozen=True)
+class TestMqlPnl0001ChamberSegmentComponents:
+    inlet_line: AmesimPnl0001Pipe
+    volume: AmesimPneumaticVolume
+    inlet_orifice: AmesimPneumaticOrifice
+    outlet_orifice: AmesimPneumaticOrifice
+    spec: TestMqlPneumaticChamberSegmentSpec
+
+
+@dataclass(frozen=True)
+class TestMqlPnl0001ChamberSegmentSnapshot:
+    inlet_line: ThermodynamicProperties
+    chamber: ThermodynamicProperties
+    inlet_node: ThermodynamicProperties
+    outlet_boundary: ThermodynamicProperties
+    node_to_line_flow: float
+    line_to_chamber_flow: float
+    outlet_flow: float
+
+
 @dataclass(frozen=True)
 class TestMqlPneumaticBranchComponents:
     name: str
@@ -379,3 +400,158 @@ class TestMqlPneumaticChamberSegmentClosure:
             internal_h=snapshot.chamber.h,
         )
         return derivative.as_vector()
+
+
+class TestMqlPnl0001ChamberSegmentClosure:
+    """Fixed chamber segment with the topology-derived inlet PNL0001 state.
+
+    The inlet line has a closed causal boundary here: port-1 pressure and
+    temperature come from the PN3 node boundary, while port-2 flow comes from
+    the fixed orifice. The outlet line remains a boundary until its three-line
+    PN3 node balance is assembled.
+    """
+
+    def __init__(
+        self,
+        *,
+        components: TestMqlPnl0001ChamberSegmentComponents,
+        inlet_node: TestMqlPneumaticBoundaryCondition,
+        outlet_boundary: TestMqlPneumaticBoundaryCondition,
+    ) -> None:
+        self.components = components
+        self.inlet_node = inlet_node
+        self.outlet_boundary = outlet_boundary
+
+    def initial_state_vector(self) -> list[float]:
+        return [
+            *self.components.inlet_line.get_state_vector(),
+            *self.components.volume.get_state_vector(),
+        ]
+
+    def apply_state_vector(self, values: list[float]) -> None:
+        if len(values) != 4:
+            raise ValueError("PNL0001/chamber segment state vector requires four values")
+        self.components.inlet_line.set_state_vector(values[:2])
+        self.components.volume.set_state_vector(values[2:])
+
+    def snapshot(
+        self,
+        state_vector: list[float] | None = None,
+    ) -> TestMqlPnl0001ChamberSegmentSnapshot:
+        if state_vector is not None:
+            self.apply_state_vector(state_vector)
+        line = self.components.inlet_line.properties()
+        chamber = self.components.volume.properties()
+        inlet_node = self.inlet_node.properties(self.components.inlet_line.gas)
+        outlet_boundary = self.outlet_boundary.properties(self.components.volume.gas)
+        node_to_line_flow = self.components.inlet_line.resistance_mass_flow(
+            port_1_pressure_pa=inlet_node.p,
+            port_1_temperature_k=inlet_node.T,
+        )
+        inlet_temperature = line.T if line.p >= chamber.p else chamber.T
+        line_to_chamber_flow = self.components.inlet_orifice.mass_flow(
+            line.p,
+            chamber.p,
+            inlet_temperature,
+        )
+        outlet_temperature = (
+            chamber.T if chamber.p >= outlet_boundary.p else outlet_boundary.T
+        )
+        outlet_flow = self.components.outlet_orifice.mass_flow(
+            chamber.p,
+            outlet_boundary.p,
+            outlet_temperature,
+        )
+        snapshot = TestMqlPnl0001ChamberSegmentSnapshot(
+            inlet_line=line,
+            chamber=chamber,
+            inlet_node=inlet_node,
+            outlet_boundary=outlet_boundary,
+            node_to_line_flow=node_to_line_flow,
+            line_to_chamber_flow=line_to_chamber_flow,
+            outlet_flow=outlet_flow,
+        )
+        self._write_port_states(snapshot)
+        return snapshot
+
+    @staticmethod
+    def _port(
+        component: AmesimPneumaticVolume | AmesimPneumaticOrifice,
+        port_name: str,
+    ) -> PortState:
+        return TestMqlPneumaticChamberSegmentClosure._port(component, port_name)
+
+    def _write_port_states(
+        self,
+        snapshot: TestMqlPnl0001ChamberSegmentSnapshot,
+    ) -> None:
+        spec = self.components.spec
+        line = self.components.inlet_line
+        chamber = self.components.volume
+        inlet_orifice = self.components.inlet_orifice
+        outlet_orifice = self.components.outlet_orifice
+
+        line.port_1.p = snapshot.inlet_node.p
+        line.port_1.m_flow = snapshot.node_to_line_flow
+        line.port_1.h_outflow = snapshot.inlet_line.h
+        line.port_2.p = snapshot.inlet_line.p
+        line.port_2.m_flow = -snapshot.line_to_chamber_flow
+
+        inlet_boundary_port = self._port(
+            inlet_orifice,
+            spec.inlet_orifice_boundary_port,
+        )
+        inlet_volume_port = self._port(inlet_orifice, spec.inlet_orifice_volume_port)
+        inlet_boundary_port.p = snapshot.inlet_line.p
+        inlet_boundary_port.m_flow = snapshot.line_to_chamber_flow
+        inlet_boundary_port.h_outflow = snapshot.inlet_line.h
+        inlet_volume_port.p = snapshot.chamber.p
+        inlet_volume_port.m_flow = -snapshot.line_to_chamber_flow
+        inlet_volume_port.h_outflow = snapshot.chamber.h
+
+        chamber_inlet_port = self._port(chamber, spec.volume_inlet_port)
+        chamber_outlet_port = self._port(chamber, spec.volume_outlet_port)
+        chamber_inlet_port.m_flow = snapshot.line_to_chamber_flow
+        chamber_outlet_port.m_flow = -snapshot.outlet_flow
+
+        outlet_volume_port = self._port(
+            outlet_orifice,
+            spec.outlet_orifice_volume_port,
+        )
+        outlet_boundary_port = self._port(
+            outlet_orifice,
+            spec.outlet_orifice_boundary_port,
+        )
+        outlet_volume_port.p = snapshot.chamber.p
+        outlet_volume_port.m_flow = snapshot.outlet_flow
+        outlet_volume_port.h_outflow = snapshot.chamber.h
+        outlet_boundary_port.p = snapshot.outlet_boundary.p
+        outlet_boundary_port.m_flow = -snapshot.outlet_flow
+        outlet_boundary_port.h_outflow = snapshot.outlet_boundary.h
+
+    def rhs(self, state_vector: list[float]) -> list[float]:
+        snapshot = self.snapshot(state_vector)
+        line_derivative = self.components.inlet_line.derivatives_from_connections(
+            port_1_m_flow=snapshot.node_to_line_flow,
+            connected_h_1=snapshot.inlet_node.h,
+            port_2_m_flow=-snapshot.line_to_chamber_flow,
+            connected_h_2=snapshot.chamber.h,
+        )
+        chamber = self.components.volume
+        spec = self.components.spec
+        chamber_derivative = chamber.derivatives_from_two_connections(
+            port_a_m_flow=self._port(chamber, "port_1").m_flow,
+            connected_h_a=(
+                snapshot.inlet_line.h
+                if spec.volume_inlet_port == "port_1"
+                else snapshot.outlet_boundary.h
+            ),
+            port_b_m_flow=self._port(chamber, "port_2").m_flow,
+            connected_h_b=(
+                snapshot.inlet_line.h
+                if spec.volume_inlet_port == "port_2"
+                else snapshot.outlet_boundary.h
+            ),
+            internal_h=snapshot.chamber.h,
+        )
+        return [*line_derivative.as_vector(), *chamber_derivative.as_vector()]

PythonModels/systems/test_mql_line_parameters.py

@@ -0,0 +1,162 @@
+from __future__ import annotations
+
+import re
+import tarfile
+from dataclasses import dataclass
+from pathlib import Path
+
+from PythonModels.systems.test_mql import CONNECTION_SPECS, GLOBAL_PARAMETERS
+from PythonModels.systems.test_mql_config import resolve_numeric_expression
+
+
+AMESIM_REFERENCE_PRESSURE_PA = 101_300.0
+
+
+@dataclass(frozen=True)
+class TestMqlPnl0001Spec:
+    alias: str
+    source_component: str
+    source_port: str
+    target_component: str
+    target_port: str
+    diameter_mm: float
+    length_m: float
+    relative_roughness: float
+    polytropic_constant: float
+    heat_transfer_coefficient: float
+    external_temperature_k: float
+    gas_type_index: int
+    mode: int
+    initial_temperature_k: float
+    initial_gauge_pressure_pa: float
+
+    @property
+    def initial_absolute_pressure_pa(self) -> float:
+        return self.initial_gauge_pressure_pa + AMESIM_REFERENCE_PRESSURE_PA
+
+
+def load_test_mql_pnl0001_specs(
+    archive_path: str | Path,
+    *,
+    cir_member: str = "test_mql_.cir",
+) -> tuple[TestMqlPnl0001Spec, ...]:
+    """Load resolved PNL0001 geometry and initial states from the AMESim source."""
+    with tarfile.open(archive_path) as archive:
+        cir_file = archive.extractfile(cir_member)
+        if cir_file is None:
+            raise ValueError(f"Missing AMESim circuit member: {cir_member}")
+        cir_text = cir_file.read().decode("latin1")
+
+    numeric_globals = {
+        name: value
+        for name, expression in GLOBAL_PARAMETERS.items()
+        if (value := resolve_numeric_expression(expression, {})) is not None
+    }
+    connections = {
+        str(connection["alias"]): connection
+        for connection in CONNECTION_SPECS
+        if connection["submodel"] == "PNL0001"
+    }
+    specs = []
+    for block in re.findall(r"<LINE>.*?</LINE>", cir_text, flags=re.DOTALL):
+        if _optional_text(block, "SUB_NAME") != "PNL0001":
+            continue
+        alias = _required_text(block, "ALIAS")
+        connection = connections.get(alias)
+        if connection is None:
+            raise ValueError(f"PNL0001 line {alias!r} is absent from CONNECTION_SPECS")
+        real_parameters = _parameter_expressions(block, "RPARAM")
+        integer_parameters = _parameter_expressions(block, "IPARAM")
+        state_values = _evar_values(block)
+        specs.append(
+            TestMqlPnl0001Spec(
+                alias=alias,
+                source_component=str(connection["source_component"]),
+                source_port=str(connection["source_port"]),
+                target_component=str(connection["target_component"]),
+                target_port=str(connection["target_port"]),
+                diameter_mm=_required_numeric(
+                    alias, "diam", real_parameters, numeric_globals
+                ),
+                length_m=_required_numeric(alias, "le", real_parameters, numeric_globals),
+                relative_roughness=_required_numeric(
+                    alias, "rr", real_parameters, numeric_globals
+                ),
+                polytropic_constant=_required_numeric(
+                    alias, "k", real_parameters, numeric_globals
+                ),
+                heat_transfer_coefficient=_required_numeric(
+                    alias, "kth", real_parameters, numeric_globals
+                ),
+                external_temperature_k=_required_numeric(
+                    alias, "extemp", real_parameters, numeric_globals
+                ),
+                gas_type_index=int(
+                    _required_numeric(alias, "gi", integer_parameters, numeric_globals)
+                ),
+                mode=int(
+                    _required_numeric(alias, "mode", integer_parameters, numeric_globals)
+                ),
+                initial_temperature_k=_required_numeric(
+                    alias, "t2", state_values, numeric_globals
+                ),
+                initial_gauge_pressure_pa=_required_numeric(
+                    alias, "p2", state_values, numeric_globals
+                ),
+            )
+        )
+    if set(connections) != {spec.alias for spec in specs}:
+        missing = sorted(set(connections) - {spec.alias for spec in specs})
+        raise ValueError(f"Missing PNL0001 parameter blocks: {missing}")
+    return tuple(specs)
+
+
+def _parameter_expressions(block: str, tag_name: str) -> dict[str, str]:
+    parameters = {}
+    for parameter_block in re.findall(
+        rf"<{tag_name}>.*?</{tag_name}>",
+        block,
+        flags=re.DOTALL,
+    ):
+        parameters[_required_text(parameter_block, "VARNAME")] = _required_text(
+            parameter_block,
+            "VALUE",
+        )
+    return parameters
+
+
+def _evar_values(block: str) -> dict[str, str]:
+    values = {}
+    for variable_block in re.findall(r"<EVAR>.*?</EVAR>", block, flags=re.DOTALL):
+        value = _optional_text(variable_block, "VALUE")
+        if value:
+            values[_required_text(variable_block, "VARNAME")] = value
+    return values
+
+
+def _required_numeric(
+    alias: str,
+    name: str,
+    expressions: dict[str, str],
+    variables: dict[str, float],
+) -> float:
+    if name not in expressions:
+        raise ValueError(f"Missing {name!r} on PNL0001 line {alias!r}")
+    value = resolve_numeric_expression(expressions[name], variables)
+    if value is None:
+        raise ValueError(
+            f"Cannot resolve {name!r}={expressions[name]!r} on PNL0001 line {alias!r}"
+        )
+    return value
+
+
+def _required_text(block: str, tag_name: str) -> str:
+    value = _optional_text(block, tag_name)
+    if value is None:
+        raise ValueError(f"Missing AMESim circuit element: {tag_name}")
+    return value
+
+
+def _optional_text(block: str, tag_name: str) -> str | None:
+    match = re.search(rf"<{tag_name}>(.*?)</{tag_name}>", block, flags=re.DOTALL)
+    return match.group(1).strip() if match is not None else None

PythonModels/systems/test_mql_pneumatic_lines.py

@@ -0,0 +1,50 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from pathlib import Path
+
+from PythonModels.components.amesim_pneumatic import (
+    HELIUM_PNEUMATIC_GAS,
+    AmesimPneumaticGas,
+)
+from PythonModels.components.amesim_pneumatic_line import AmesimPnl0001Pipe
+from PythonModels.systems.test_mql_line_parameters import (
+    TestMqlPnl0001Spec,
+    load_test_mql_pnl0001_specs,
+)
+
+
+@dataclass(frozen=True)
+class TestMqlPnl0001Assembly:
+    specs: tuple[TestMqlPnl0001Spec, ...]
+    lines: dict[str, AmesimPnl0001Pipe]
+
+    def spec(self, alias: str) -> TestMqlPnl0001Spec:
+        for spec in self.specs:
+            if spec.alias == alias:
+                return spec
+        raise KeyError(alias)
+
+
+def build_test_mql_pnl0001_assembly(
+    archive_path: str | Path,
+    *,
+    gas: AmesimPneumaticGas = HELIUM_PNEUMATIC_GAS,
+) -> TestMqlPnl0001Assembly:
+    specs = load_test_mql_pnl0001_specs(archive_path)
+    lines = {
+        spec.alias: AmesimPnl0001Pipe(
+            name=spec.alias,
+            diameter_mm=spec.diameter_mm,
+            length_m=spec.length_m,
+            relative_roughness=spec.relative_roughness,
+            polytropic_constant=spec.polytropic_constant,
+            heat_transfer_coefficient=spec.heat_transfer_coefficient,
+            external_temperature_k=spec.external_temperature_k,
+            gas=gas,
+            p0=spec.initial_absolute_pressure_pa,
+            T0=spec.initial_temperature_k,
+        )
+        for spec in specs
+    }
+    return TestMqlPnl0001Assembly(specs=specs, lines=lines)

tests/test_amesim_pnl0001_pipe.py

@@ -0,0 +1,71 @@
+from __future__ import annotations
+
+import unittest
+
+from PythonModels.components.amesim_pneumatic_line import AmesimPnl0001Pipe
+
+
+class AmesimPnl0001PipeTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.pipe = AmesimPnl0001Pipe(
+            name="pneumatic_96",
+            diameter_mm=14.0,
+            length_m=1.0,
+            relative_roughness=0.045 / 14.0,
+            p0=15.3e6,
+            T0=293.15,
+        )
+
+    def test_initial_state_uses_real_pipe_volume_and_two_states(self) -> None:
+        properties = self.pipe.properties()
+
+        self.assertAlmostEqual(self.pipe.volume, 1.539380400258999e-4)
+        self.assertEqual(len(self.pipe.get_state_vector()), 2)
+        self.assertAlmostEqual(properties.p, 15.3e6, delta=1.0e-5)
+        self.assertAlmostEqual(properties.T, 293.15)
+        self.assertAlmostEqual(self.pipe.gas_mass_g(), 3.716965219188, places=10)
+
+    def test_resistance_flow_follows_pressure_gradient(self) -> None:
+        forward = self.pipe.resistance_mass_flow(
+            port_1_pressure_pa=15.31e6,
+            port_1_temperature_k=293.15,
+        )
+        reverse = self.pipe.resistance_mass_flow(
+            port_1_pressure_pa=15.29e6,
+            port_1_temperature_k=293.15,
+        )
+
+        self.assertGreater(forward, 0.0)
+        self.assertLess(reverse, 0.0)
+        self.assertAlmostEqual(abs(forward), abs(reverse), delta=abs(forward) * 0.01)
+
+    def test_diagnostics_reproduce_laminar_friction_contract(self) -> None:
+        diagnostics = self.pipe.diagnostics(mass_flow_kg_s=8.90603914774626e-6)
+
+        self.assertGreater(diagnostics.reynolds_number, 40.0)
+        self.assertLess(diagnostics.reynolds_number, 45.0)
+        self.assertAlmostEqual(
+            diagnostics.friction_factor,
+            64.0 / diagnostics.reynolds_number,
+        )
+        self.assertGreater(diagnostics.gas_velocity_m_s, 0.0)
+        self.assertGreater(diagnostics.pressure_drop_pa, 0.0)
+
+    def test_connection_derivative_preserves_mass_and_stream_direction(self) -> None:
+        internal = self.pipe.properties()
+        derivative = self.pipe.derivatives_from_connections(
+            port_1_m_flow=0.2,
+            connected_h_1=internal.h + 1000.0,
+            port_2_m_flow=-0.1,
+            connected_h_2=internal.h - 1000.0,
+        )
+
+        self.assertAlmostEqual(derivative.m, 0.1)
+        self.assertAlmostEqual(
+            derivative.U,
+            0.2 * (internal.h + 1000.0) - 0.1 * internal.h,
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_test_mql_pnl0001.py

@@ -0,0 +1,82 @@
+from __future__ import annotations
+
+import unittest
+from pathlib import Path
+
+from PythonModels.reporting.amesim_results import load_test_mql_amesim_results
+from PythonModels.systems.test_mql_line_parameters import load_test_mql_pnl0001_specs
+from PythonModels.systems.test_mql_pneumatic_lines import (
+    build_test_mql_pnl0001_assembly,
+)
+
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+TEST_MQL_AME = REPO_ROOT / "AmesimModels" / "test_mql.ame"
+
+
+class TestMqlPnl0001Tests(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls) -> None:
+        cls.specs = load_test_mql_pnl0001_specs(TEST_MQL_AME)
+        cls.assembly = build_test_mql_pnl0001_assembly(TEST_MQL_AME)
+        cls.results = load_test_mql_amesim_results(TEST_MQL_AME)
+
+    def test_loads_all_real_pnl0001_parameters_from_cir(self) -> None:
+        self.assertEqual(len(self.specs), 20)
+        spec = self.assembly.spec("pneumatic_96")
+
+        self.assertEqual(spec.source_component, "pn_node3_8")
+        self.assertEqual(spec.target_component, "pn_orifice_18")
+        self.assertEqual(spec.diameter_mm, 14.0)
+        self.assertEqual(spec.length_m, 1.0)
+        self.assertAlmostEqual(spec.relative_roughness, 0.045 / 14.0)
+        self.assertEqual(spec.polytropic_constant, 1.35)
+        self.assertEqual(spec.heat_transfer_coefficient, 0.0)
+        self.assertEqual(spec.external_temperature_k, 293.15)
+        self.assertEqual(spec.gas_type_index, 1)
+        self.assertEqual(spec.mode, 2)
+        self.assertAlmostEqual(spec.initial_gauge_pressure_pa, 15_198_700.0)
+        self.assertAlmostEqual(spec.initial_absolute_pressure_pa, 15_300_000.0)
+
+    def test_builds_twenty_two_state_physical_line_components(self) -> None:
+        self.assertEqual(len(self.assembly.lines), 20)
+        self.assertTrue(
+            all(len(line.get_state_vector()) == 2 for line in self.assembly.lines.values())
+        )
+
+    def test_pneumatic_96_initial_observables_match_amesim_baseline(self) -> None:
+        pipe = self.assembly.lines["pneumatic_96"]
+
+        self.assertAlmostEqual(
+            pipe.properties().p - 101_300.0,
+            self.results.series("p2@pneumatic_96")[0],
+            delta=1.0e-5,
+        )
+        self.assertAlmostEqual(
+            pipe.properties().T,
+            self.results.series("t2@pneumatic_96")[0],
+        )
+        self.assertAlmostEqual(
+            pipe.gas_mass_g(),
+            self.results.series("mgas@pneumatic_96")[0],
+            delta=0.005,
+        )
+
+    def test_baseline_mass_balance_identifies_port_two_input_sign(self) -> None:
+        mass = self.results.series("mgas@pneumatic_96")
+        dm1 = self.results.series("dm1@pneumatic_96")
+        dm2_peer = self.results.series("dm2@pn_orifice_18")
+        index = 500
+        finite_difference = (mass[index] - mass[index - 1]) / (
+            self.results.times[index] - self.results.times[index - 1]
+        )
+
+        self.assertAlmostEqual(
+            finite_difference,
+            dm2_peer[index] - dm1[index],
+            delta=3.0e-5,
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_test_mql_pnl0001_segment.py

@@ -0,0 +1,80 @@
+from __future__ import annotations
+
+import unittest
+
+from PythonModels.core.solver import SolveIVPConfig
+from PythonModels.systems.test_mql import TestMqlSystem
+
+
+class TestMqlPnl0001ChamberSegmentTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.system = TestMqlSystem()
+        self.spec = self.system.discover_pneumatic_branch_topology().chamber_segment_specs[0]
+
+    def test_system_assembles_all_twenty_physical_pnl0001_lines(self) -> None:
+        self.assertEqual(self.system.typed_pnl0001_line_count, 20)
+        self.assertIn("pneumatic_96", self.system.pnl0001_assembly.lines)
+
+    def test_closure_inserts_topology_derived_inlet_line(self) -> None:
+        closure = self.system.pnl0001_chamber_segment_closure_from_spec(
+            self.spec,
+            inlet_node_pressure_pa=16.0e6,
+            outlet_pressure_pa=15.3e6,
+        )
+
+        snapshot = closure.snapshot()
+        rhs = closure.rhs(closure.initial_state_vector())
+
+        self.assertEqual(closure.components.inlet_line.name, "pneumatic_96")
+        self.assertEqual(len(closure.initial_state_vector()), 4)
+        self.assertEqual(len(rhs), 4)
+        self.assertGreater(snapshot.node_to_line_flow, 0.0)
+        self.assertAlmostEqual(snapshot.line_to_chamber_flow, 0.0, delta=1.0e-7)
+        self.assertAlmostEqual(snapshot.outlet_flow, 0.0, delta=1.0e-7)
+        self.assertAlmostEqual(rhs[0] + rhs[2], snapshot.node_to_line_flow)
+
+    def test_internal_line_orifice_flow_cancels_from_total_mass_balance(self) -> None:
+        closure = self.system.pnl0001_chamber_segment_closure_from_spec(
+            self.spec,
+            inlet_node_pressure_pa=15.3e6,
+            outlet_pressure_pa=14.0e6,
+        )
+        state = closure.initial_state_vector()
+        state[0] *= 1.01
+        state[1] *= 1.01
+
+        snapshot = closure.snapshot(state)
+        rhs = closure.rhs(state)
+
+        self.assertGreater(snapshot.line_to_chamber_flow, 0.0)
+        self.assertAlmostEqual(
+            rhs[0] + rhs[2],
+            snapshot.node_to_line_flow - snapshot.outlet_flow,
+            delta=1.0e-12,
+        )
+        self.assertAlmostEqual(
+            closure.components.inlet_line.port_2.m_flow,
+            -snapshot.line_to_chamber_flow,
+        )
+
+    def test_simulates_four_state_line_chamber_segment(self) -> None:
+        solution = self.system.simulate_pnl0001_chamber_segment_from_spec(
+            self.spec,
+            inlet_node_pressure_pa=15.31e6,
+            outlet_pressure_pa=15.29e6,
+            config=SolveIVPConfig(
+                t_start=0.0,
+                t_stop=1.0e-7,
+                max_step=1.0e-8,
+            ),
+            t_eval=[0.0, 5.0e-8, 1.0e-7],
+        )
+
+        self.assertTrue(solution.success)
+        self.assertEqual(len(solution.t), 3)
+        self.assertEqual(len(solution.y), 4)
+        self.assertEqual([len(row) for row in solution.y], [3, 3, 3, 3])
+
+
+if __name__ == "__main__":
+    unittest.main()