接入test_mql pn_node3_14固定气室支路

PythonModels/systems/test_mql.py

@@ -4615,6 +4615,15 @@ class TestMqlSystem:
                     return self.node3_assembly[line_spec.source_component]
             raise KeyError(f"No remote PN3 node found for {line_alias}")
 
+        def chamber_segment_for_inlet_node(node_alias: str):
+            chamber_specs = (
+                self.discover_pneumatic_branch_topology().chamber_segment_specs
+            )
+            for chamber_spec in chamber_specs:
+                if chamber_spec.inlet_node_alias == node_alias:
+                    return chamber_spec
+            raise KeyError(f"No fixed chamber segment starts at {node_alias}")
+
         inlet_line = self.pnl0001_assembly.lines[spec.inlet_line_alias]
         outlet_line = self.pnl0001_assembly.lines[spec.outlet_line_alias]
         node_line_spec = self._pnl0003_spec_for_node_port(
@@ -4812,6 +4821,24 @@ class TestMqlSystem:
         p4_port3_next_orifice_output_line = self.pnl0001_assembly.lines[
             p4_port3_next_orifice_output_spec.alias
         ]
+        p4_port3_next_chamber_spec = chamber_segment_for_inlet_node(
+            p4_port3_next_orifice_node.alias
+        )
+        p4_port3_next_chamber_inlet_line = self.pnl0001_assembly.lines[
+            p4_port3_next_chamber_spec.inlet_line_alias
+        ]
+        p4_port3_next_chamber = self.network.components[
+            p4_port3_next_chamber_spec.volume_alias
+        ]
+        p4_port3_next_chamber_outlet_line = self.pnl0001_assembly.lines[
+            p4_port3_next_chamber_spec.outlet_line_alias
+        ]
+        p4_port3_next_chamber_inlet_orifice = self.pneumatic_assembly.fixed_orifices[
+            p4_port3_next_chamber_spec.inlet_orifice_alias
+        ]
+        p4_port3_next_chamber_outlet_orifice = self.pneumatic_assembly.fixed_orifices[
+            p4_port3_next_chamber_spec.outlet_orifice_alias
+        ]
         p4_port3_remote_orifice = self.pneumatic_assembly.variable_orifices[
             p4_port3_remote_neighborhood.port_4.orifice_alias
         ]
@@ -4897,6 +4924,18 @@ class TestMqlSystem:
             raise TypeError(
                 f"{p4_port3_next_orifice_alias} is not an AMESim pneumatic orifice"
             )
+        if not isinstance(p4_port3_next_chamber, AmesimPneumaticVolume):
+            raise TypeError(
+                f"{p4_port3_next_chamber_spec.volume_alias} is not an AMESim pneumatic volume"
+            )
+        if not isinstance(p4_port3_next_chamber_inlet_orifice, AmesimPneumaticOrifice):
+            raise TypeError(
+                f"{p4_port3_next_chamber_spec.inlet_orifice_alias} is not an AMESim pneumatic orifice"
+            )
+        if not isinstance(p4_port3_next_chamber_outlet_orifice, AmesimPneumaticOrifice):
+            raise TypeError(
+                f"{p4_port3_next_chamber_spec.outlet_orifice_alias} is not an AMESim pneumatic orifice"
+            )
         if not isinstance(p4_bridge_primary_chamber, AmesimPneumaticVolume):
             raise TypeError(
                 f"{p4_bridge_primary_chamber_alias} is not an AMESim pneumatic volume"
@@ -4960,6 +4999,12 @@ class TestMqlSystem:
                 p4_port3_next_orifice_line=p4_port3_next_orifice_line,
                 p4_port3_next_orifice_node=p4_port3_next_orifice_node,
                 p4_port3_next_orifice_output_line=p4_port3_next_orifice_output_line,
+                p4_port3_next_chamber_inlet_line=p4_port3_next_chamber_inlet_line,
+                p4_port3_next_chamber=p4_port3_next_chamber,
+                p4_port3_next_chamber_outlet_line=p4_port3_next_chamber_outlet_line,
+                p4_port3_next_chamber_inlet_orifice=p4_port3_next_chamber_inlet_orifice,
+                p4_port3_next_chamber_outlet_orifice=p4_port3_next_chamber_outlet_orifice,
+                p4_port3_next_chamber_spec=p4_port3_next_chamber_spec,
                 p4_port3_remote_orifice=p4_port3_remote_orifice,
                 p4_port3_remote_orifice_line=p4_port3_remote_orifice_line,
                 p4_port3_remote_orifice_node=p4_port3_remote_orifice_node,

PythonModels/systems/test_mql_closure.py

@@ -235,6 +235,12 @@ class TestMqlPn3P4NodeChamberSegmentComponents:
     p4_port3_next_orifice_line: AmesimPnl0003Pipe
     p4_port3_next_orifice_node: TestMqlPneumaticNode3
     p4_port3_next_orifice_output_line: AmesimPnl0001Pipe
+    p4_port3_next_chamber_inlet_line: AmesimPnl0001Pipe
+    p4_port3_next_chamber: AmesimPneumaticVolume
+    p4_port3_next_chamber_outlet_line: AmesimPnl0001Pipe
+    p4_port3_next_chamber_inlet_orifice: AmesimPneumaticOrifice
+    p4_port3_next_chamber_outlet_orifice: AmesimPneumaticOrifice
+    p4_port3_next_chamber_spec: TestMqlPneumaticChamberSegmentSpec
     p4_port3_remote_orifice: AmesimPneumaticOrifice
     p4_port3_remote_orifice_line: AmesimPnl0003Pipe
     p4_port3_remote_orifice_node: TestMqlPneumaticNode3
@@ -286,6 +292,9 @@ class TestMqlPn3P4NodeChamberSegmentSnapshot:
     p4_port3_next_orifice_line_port_1: ThermodynamicProperties
     p4_port3_next_orifice_line_port_2: ThermodynamicProperties
     p4_port3_next_orifice_output_line: ThermodynamicProperties
+    p4_port3_next_chamber_inlet_line: ThermodynamicProperties
+    p4_port3_next_chamber: ThermodynamicProperties
+    p4_port3_next_chamber_outlet_line: ThermodynamicProperties
     p4_port3_remote_orifice_line_port_1: ThermodynamicProperties
     p4_port3_remote_orifice_line_port_2: ThermodynamicProperties
     p4_port3_remote_resistance_node_line_port_1: ThermodynamicProperties
@@ -353,6 +362,10 @@ class TestMqlPn3P4NodeChamberSegmentSnapshot:
     p4_port3_next_orifice_line_center_flow: float
     p4_port3_next_orifice_to_output_line_flow: float
     p4_port3_next_orifice_output_to_p4_flow: float
+    p4_port3_next_chamber_inlet_node_to_line_flow: float
+    p4_port3_next_chamber_inlet_line_to_chamber_flow: float
+    p4_port3_next_chamber_outlet_node_to_line_flow: float
+    p4_port3_next_chamber_outlet_line_to_chamber_flow: float
     p4_port3_remote_node_to_orifice_line_flow: float
     p4_port3_remote_node_to_resistance_flow: float
     p4_port3_remote_resistance_node_to_line_flow: float
@@ -418,11 +431,14 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
             *self.components.p4_port3_remote_orifice_line.get_state_vector(),
             *self.components.p4_port3_next_orifice_line.get_state_vector(),
             *self.components.p4_port3_next_orifice_output_line.get_state_vector(),
+            *self.components.p4_port3_next_chamber_inlet_line.get_state_vector(),
+            *self.components.p4_port3_next_chamber.get_state_vector(),
+            *self.components.p4_port3_next_chamber_outlet_line.get_state_vector(),
         ]
 
     def apply_state_vector(self, values: list[float]) -> None:
-        if len(values) != 78:
-            raise ValueError("PN3/P4 node chamber segment state vector requires seventy-eight values")
+        if len(values) != 84:
+            raise ValueError("PN3/P4 node chamber segment state vector requires eighty-four values")
         self.components.inlet_line.set_state_vector(values[:2])
         self.components.volume.set_state_vector(values[2:4])
         self.components.outlet_line.set_state_vector(values[4:6])
@@ -456,7 +472,10 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
         self.components.p4_port3_remote_resistance_output_line.set_state_vector(values[66:68])
         self.components.p4_port3_remote_orifice_line.set_state_vector(values[68:72])
         self.components.p4_port3_next_orifice_line.set_state_vector(values[72:76])
-        self.components.p4_port3_next_orifice_output_line.set_state_vector(values[76:])
+        self.components.p4_port3_next_orifice_output_line.set_state_vector(values[76:78])
+        self.components.p4_port3_next_chamber_inlet_line.set_state_vector(values[78:80])
+        self.components.p4_port3_next_chamber.set_state_vector(values[80:82])
+        self.components.p4_port3_next_chamber_outlet_line.set_state_vector(values[82:])
 
     def snapshot(
         self,
@@ -528,6 +547,13 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
         p4_port3_next_orifice_output_line = (
             self.components.p4_port3_next_orifice_output_line.properties()
         )
+        p4_port3_next_chamber_inlet_line = (
+            self.components.p4_port3_next_chamber_inlet_line.properties()
+        )
+        p4_port3_next_chamber = self.components.p4_port3_next_chamber.properties()
+        p4_port3_next_chamber_outlet_line = (
+            self.components.p4_port3_next_chamber_outlet_line.properties()
+        )
         p4_port3_remote_orifice_line_port_1 = (
             self.components.p4_port3_remote_orifice_line.properties_1()
         )
@@ -755,12 +781,38 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
                 port_temperature_k=p4_port3_next_primary_line.T,
             )
         )
+        p4_port3_next_chamber_inlet_node_to_line_flow = (
+            self.components.p4_port3_next_chamber_inlet_line.resistance_mass_flow(
+                port_1_pressure_pa=p4_port3_next_orifice_line_port_1.p,
+                port_1_temperature_k=p4_port3_next_orifice_line_port_1.T,
+            )
+        )
+        p4_port3_next_chamber_inlet_line_to_chamber_flow = self._line_to_chamber_flow(
+            line=p4_port3_next_chamber_inlet_line,
+            chamber=p4_port3_next_chamber,
+            orifice=self.components.p4_port3_next_chamber_inlet_orifice,
+        )
+        p4_port3_next_chamber_outlet_node_to_line_flow = (
+            self.components.p4_port3_next_chamber_outlet_line.resistance_mass_flow(
+                port_1_pressure_pa=p4_port3_remote_resistance_node_line_port_1.p,
+                port_1_temperature_k=p4_port3_remote_resistance_node_line_port_1.T,
+            )
+        )
+        p4_port3_next_chamber_outlet_line_to_chamber_flow = self._line_to_chamber_flow(
+            line=p4_port3_next_chamber_outlet_line,
+            chamber=p4_port3_next_chamber,
+            orifice=self.components.p4_port3_next_chamber_outlet_orifice,
+        )
         p4_port3_next_orifice_node_balance = (
             self.components.p4_port3_next_orifice_node.balance(
                 port_2_temperature_k=p4_port3_next_orifice_line_port_1.T,
                 port_2_pressure_pa=p4_port3_next_orifice_line_port_1.p,
-                port_1_enthalpy_flow_w=0.0,
-                port_1_mass_flow_g_s=0.0,
+                port_1_enthalpy_flow_w=self._enthalpy_flow_from_node(
+                    flow_kg_s=p4_port3_next_chamber_inlet_node_to_line_flow,
+                    node_h=p4_port3_next_orifice_line_port_1.h,
+                    connected_h=p4_port3_next_chamber_inlet_line.h,
+                ),
+                port_1_mass_flow_g_s=p4_port3_next_chamber_inlet_node_to_line_flow * 1.0e3,
                 port_3_enthalpy_flow_w=0.0,
                 port_3_mass_flow_g_s=0.0,
             )
@@ -818,8 +870,12 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
                     connected_h=p4_port3_remote_orifice_line_port_1.h,
                 ),
                 port_1_mass_flow_g_s=-p4_port3_remote_node_to_resistance_flow * 1.0e3,
-                port_3_enthalpy_flow_w=0.0,
-                port_3_mass_flow_g_s=0.0,
+                port_3_enthalpy_flow_w=self._enthalpy_flow_from_node(
+                    flow_kg_s=p4_port3_next_chamber_outlet_node_to_line_flow,
+                    node_h=p4_port3_remote_resistance_node_line_port_1.h,
+                    connected_h=p4_port3_next_chamber_outlet_line.h,
+                ),
+                port_3_mass_flow_g_s=p4_port3_next_chamber_outlet_node_to_line_flow * 1.0e3,
             )
         )
         p4_port3_remote_resistance_node_to_line_flow = (
@@ -1081,6 +1137,9 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
             p4_port3_next_orifice_line_port_1=p4_port3_next_orifice_line_port_1,
             p4_port3_next_orifice_line_port_2=p4_port3_next_orifice_line_port_2,
             p4_port3_next_orifice_output_line=p4_port3_next_orifice_output_line,
+            p4_port3_next_chamber_inlet_line=p4_port3_next_chamber_inlet_line,
+            p4_port3_next_chamber=p4_port3_next_chamber,
+            p4_port3_next_chamber_outlet_line=p4_port3_next_chamber_outlet_line,
             p4_port3_remote_orifice_line_port_1=p4_port3_remote_orifice_line_port_1,
             p4_port3_remote_orifice_line_port_2=p4_port3_remote_orifice_line_port_2,
             p4_port3_remote_resistance_node_line_port_1=(
@@ -1180,6 +1239,18 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
             p4_port3_next_orifice_output_to_p4_flow=(
                 p4_port3_next_orifice_output_to_p4_flow
             ),
+            p4_port3_next_chamber_inlet_node_to_line_flow=(
+                p4_port3_next_chamber_inlet_node_to_line_flow
+            ),
+            p4_port3_next_chamber_inlet_line_to_chamber_flow=(
+                p4_port3_next_chamber_inlet_line_to_chamber_flow
+            ),
+            p4_port3_next_chamber_outlet_node_to_line_flow=(
+                p4_port3_next_chamber_outlet_node_to_line_flow
+            ),
+            p4_port3_next_chamber_outlet_line_to_chamber_flow=(
+                p4_port3_next_chamber_outlet_line_to_chamber_flow
+            ),
             p4_port3_remote_node_to_orifice_line_flow=(
                 p4_port3_remote_node_to_orifice_line_flow
             ),
@@ -1566,6 +1637,43 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
         p4_port3_next_orifice_output_line.port_2.m_flow = -snapshot.p4_port3_next_orifice_output_to_p4_flow
         p4_port3_next_orifice_output_line.port_2.h_outflow = snapshot.p4_port3_next_orifice_output_line.h
 
+        chamber_spec = self.components.p4_port3_next_chamber_spec
+        p4_port3_next_chamber = self.components.p4_port3_next_chamber
+        p4_port3_next_chamber_inlet_port = self._port(
+            p4_port3_next_chamber,
+            chamber_spec.volume_inlet_port,
+        )
+        p4_port3_next_chamber_outlet_port = self._port(
+            p4_port3_next_chamber,
+            chamber_spec.volume_outlet_port,
+        )
+        TestMqlPnl0001PairChamberSegmentClosure._write_line_side(
+            self,
+            line=self.components.p4_port3_next_chamber_inlet_line,
+            line_properties=snapshot.p4_port3_next_chamber_inlet_line,
+            node_properties=snapshot.p4_port3_next_orifice_line_port_1,
+            node_to_line_flow=snapshot.p4_port3_next_chamber_inlet_node_to_line_flow,
+            line_to_chamber_flow=snapshot.p4_port3_next_chamber_inlet_line_to_chamber_flow,
+            orifice=self.components.p4_port3_next_chamber_inlet_orifice,
+            orifice_boundary_port=chamber_spec.inlet_orifice_boundary_port,
+            orifice_volume_port=chamber_spec.inlet_orifice_volume_port,
+            chamber_port=p4_port3_next_chamber_inlet_port,
+            chamber_properties=snapshot.p4_port3_next_chamber,
+        )
+        TestMqlPnl0001PairChamberSegmentClosure._write_line_side(
+            self,
+            line=self.components.p4_port3_next_chamber_outlet_line,
+            line_properties=snapshot.p4_port3_next_chamber_outlet_line,
+            node_properties=snapshot.p4_port3_remote_resistance_node_line_port_1,
+            node_to_line_flow=snapshot.p4_port3_next_chamber_outlet_node_to_line_flow,
+            line_to_chamber_flow=snapshot.p4_port3_next_chamber_outlet_line_to_chamber_flow,
+            orifice=self.components.p4_port3_next_chamber_outlet_orifice,
+            orifice_boundary_port=chamber_spec.outlet_orifice_boundary_port,
+            orifice_volume_port=chamber_spec.outlet_orifice_volume_port,
+            chamber_port=p4_port3_next_chamber_outlet_port,
+            chamber_properties=snapshot.p4_port3_next_chamber,
+        )
+
         p4_port3_remote_orifice_line = self.components.p4_port3_remote_orifice_line
         p4_port3_remote_orifice_line.port_1.p = snapshot.p4_port3_remote_orifice_line_port_1.p
         p4_port3_remote_orifice_line.port_1.m_flow = snapshot.p4_port3_remote_node_to_orifice_line_flow
@@ -1898,6 +2006,41 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
                 connected_h_2=snapshot.p4_port3_next_primary_line.h,
             )
         )
+        p4_port3_next_chamber_inlet_derivative = (
+            self.components.p4_port3_next_chamber_inlet_line.derivatives_from_connections(
+                port_1_m_flow=snapshot.p4_port3_next_chamber_inlet_node_to_line_flow,
+                connected_h_1=snapshot.p4_port3_next_orifice_line_port_1.h,
+                port_2_m_flow=-snapshot.p4_port3_next_chamber_inlet_line_to_chamber_flow,
+                connected_h_2=snapshot.p4_port3_next_chamber.h,
+            )
+        )
+        p4_port3_next_chamber_spec = self.components.p4_port3_next_chamber_spec
+        p4_port3_next_chamber = self.components.p4_port3_next_chamber
+        p4_port3_next_fixed_chamber_derivative = (
+            p4_port3_next_chamber.derivatives_from_two_connections(
+                port_a_m_flow=self._port(p4_port3_next_chamber, "port_1").m_flow,
+                connected_h_a=(
+                    snapshot.p4_port3_next_chamber_inlet_line.h
+                    if p4_port3_next_chamber_spec.volume_inlet_port == "port_1"
+                    else snapshot.p4_port3_next_chamber_outlet_line.h
+                ),
+                port_b_m_flow=self._port(p4_port3_next_chamber, "port_2").m_flow,
+                connected_h_b=(
+                    snapshot.p4_port3_next_chamber_inlet_line.h
+                    if p4_port3_next_chamber_spec.volume_inlet_port == "port_2"
+                    else snapshot.p4_port3_next_chamber_outlet_line.h
+                ),
+                internal_h=snapshot.p4_port3_next_chamber.h,
+            )
+        )
+        p4_port3_next_chamber_outlet_derivative = (
+            self.components.p4_port3_next_chamber_outlet_line.derivatives_from_connections(
+                port_1_m_flow=snapshot.p4_port3_next_chamber_outlet_node_to_line_flow,
+                connected_h_1=snapshot.p4_port3_remote_resistance_node_line_port_1.h,
+                port_2_m_flow=-snapshot.p4_port3_next_chamber_outlet_line_to_chamber_flow,
+                connected_h_2=snapshot.p4_port3_next_chamber.h,
+            )
+        )
         return [
             *inlet_derivative.as_vector(),
             *chamber_derivative.as_vector(),
@@ -1938,6 +2081,9 @@ class TestMqlPn3P4NodeChamberSegmentClosure:
             *p4_port3_next_orifice_derivative_1.as_vector(),
             *p4_port3_next_orifice_derivative_2.as_vector(),
             *p4_port3_next_orifice_output_derivative.as_vector(),
+            *p4_port3_next_chamber_inlet_derivative.as_vector(),
+            *p4_port3_next_fixed_chamber_derivative.as_vector(),
+            *p4_port3_next_chamber_outlet_derivative.as_vector(),
         ]
 
 

tests/test_test_mql_pnl0001_segment.py

@@ -364,6 +364,26 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
             closure.components.p4_port3_next_orifice_output_line.name,
             "pneumatic_93",
         )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_inlet_line.name,
+            "pneumatic_103",
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber.name,
+            "pn_general_chamber_5",
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_outlet_line.name,
+            "pneumatic_104",
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_inlet_orifice.name,
+            "pn_orifice_24",
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_outlet_orifice.name,
+            "pn_orifice_25",
+        )
         self.assertEqual(
             closure.components.p4_port3_remote_orifice.name,
             "pn_morifice_1",
@@ -396,8 +416,8 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
             closure.components.p4_port3_remote_resistance_output_line.name,
             "pneumatic_94",
         )
-        self.assertEqual(len(closure.initial_state_vector()), 78)
-        self.assertEqual(len(rhs), 78)
+        self.assertEqual(len(closure.initial_state_vector()), 84)
+        self.assertEqual(len(rhs), 84)
         self.assertAlmostEqual(
             snapshot.p4_balance.pressure_pa,
             snapshot.p4_primary_line.p,
@@ -570,6 +590,21 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
             closure.components.p4_port3_next_orifice_node.alias,
             "pn_node3_14",
         )
+        chamber_segment = (
+            self.system.discover_pneumatic_branch_topology().chamber_segment_specs[3]
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_spec,
+            chamber_segment,
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_inlet_line.name,
+            chamber_segment.inlet_line_alias,
+        )
+        self.assertEqual(
+            closure.components.p4_port3_next_chamber_outlet_line.name,
+            chamber_segment.outlet_line_alias,
+        )
         self.assertEqual(
             closure.components.p4_port3_remote_orifice.name,
             port3_remote_neighborhood.port_4.orifice_alias,
@@ -692,8 +727,10 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
             delta=1.0e-12,
         )
         self.assertAlmostEqual(
-            snapshot.p4_port3_remote_resistance_node_to_line_flow,
-            snapshot.p4_port3_remote_node_to_resistance_flow,
+            snapshot.p4_port3_remote_resistance_node_to_line_flow
+            - snapshot.p4_port3_remote_node_to_resistance_flow
+            + snapshot.p4_port3_next_chamber_outlet_node_to_line_flow,
+            0.0,
             delta=1.0e-12,
         )
         self.assertAlmostEqual(
@@ -718,7 +755,8 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
             delta=1.0e-12,
         )
         self.assertAlmostEqual(
-            snapshot.p4_port3_next_orifice_node_to_line_flow,
+            snapshot.p4_port3_next_orifice_node_to_line_flow
+            + snapshot.p4_port3_next_chamber_inlet_node_to_line_flow,
             0.0,
             delta=1.0e-12,
         )
@@ -727,14 +765,23 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
             snapshot.p4_port3_next_orifice_to_output_line_flow,
             delta=1.0e-12,
         )
-        mass_derivative_sum = sum(rhs[index] for index in range(0, 78, 2))
+        next_chamber_mass_sum = rhs[78] + rhs[80] + rhs[82]
+        self.assertAlmostEqual(
+            next_chamber_mass_sum,
+            (
+                snapshot.p4_port3_next_chamber_inlet_node_to_line_flow
+                + snapshot.p4_port3_next_chamber_outlet_node_to_line_flow
+            ),
+            delta=1.0e-12,
+        )
+        mass_derivative_sum = sum(rhs[index] for index in range(0, 84, 2))
         self.assertAlmostEqual(
             mass_derivative_sum,
             0.0,
             delta=1.0e-12,
         )
 
-    def test_simulates_seventy_eight_state_pn3_p4_node_chamber_segment(self) -> None:
+    def test_simulates_eighty_four_state_pn3_p4_node_chamber_segment(self) -> None:
         solution = self.system.simulate_pn3_p4_node_chamber_segment_from_spec(
             self.spec,
             inlet_node_pressure_pa=15.31e6,
@@ -749,8 +796,8 @@ class TestMqlPn3P4NodeChamberSegmentTests(unittest.TestCase):
 
         self.assertTrue(solution.success)
         self.assertEqual(len(solution.t), 3)
-        self.assertEqual(len(solution.y), 78)
-        self.assertEqual([len(row) for row in solution.y], [3] * 78)
+        self.assertEqual(len(solution.y), 84)
+        self.assertEqual([len(row) for row in solution.y], [3] * 84)
 
 
 if __name__ == "__main__":