perf: retain exact flow caches and compiled targets

app/simulation/components/amesim/flow/orifices.py

@@ -716,6 +716,7 @@ class AmesimPnvo001FixedOpening(AlgebraicComponent):
             upstream_temperature=self._upstream_temperature("port_3"),
         )
 
+    @lru_cache(maxsize=32768)
     def _one_way_flow_characteristics(
         self,
         *,

app/simulation/components/amesim/flow/pipes.py

@@ -267,6 +267,7 @@ class AmesimPnl00r(AlgebraicComponent):
         )
         return magnitude if mass_flow > 0.0 else -magnitude
 
+    @lru_cache(maxsize=32768)
     def _mass_flow_for_pressure_drop(
         self,
         pressure_drop: float,
@@ -1378,6 +1379,7 @@ class AmesimPnl0003(DynamicComponent):
         magnitude = friction * (self.le / self.diam) * density * velocity * velocity / 2.0
         return magnitude if mass_flow > 0.0 else -magnitude
 
+    @lru_cache(maxsize=32768)
     def _mass_flow_for_pressure_drop(
         self,
         pressure_drop: float,

app/simulation/solvers/algebraic.py

@@ -327,6 +327,14 @@ class PressureFlowSolver:
             selected: self._filter_explicit_flow_plan(selected)
             for selected in (frozenset(("f", "m_flow")), frozenset(("f",)))
         }
+        self._explicit_flow_unknowns_by_variables = {
+            selected: tuple(
+                unknown
+                for unknown in self.unknowns
+                if unknown.variable in selected
+            )
+            for selected in self._explicit_flow_plans_by_variables
+        }
         self._equation_scale_plans = self._build_equation_scale_plans(
             self._equation_templates
         )
@@ -1519,6 +1527,25 @@ class PressureFlowSolver:
 
         return read_component_equation
 
+    def _connection_flow_target_reader(
+        self,
+        equation,
+        unknown: AlgebraicUnknown,
+    ) -> Callable[[], float]:
+        if equation.relation != "sumToZero" or len(equation.variables) != 2:
+            raise ValueError(
+                f"Connection flow equation {equation.id} must sum two variables."
+            )
+        first = self._unknowns_by_id[equation.variables[0]]
+        second = self._unknowns_by_id[equation.variables[1]]
+        if unknown is first:
+            return lambda: 0.0 - (0.0 + second.read())
+        if unknown is second:
+            return lambda: 0.0 - (first.read() + 0.0)
+        raise ValueError(
+            f"Connection flow equation {equation.id} does not contain {unknown.id}."
+        )
+
     def _pressure_flow_equation_values(self) -> tuple[float, ...]:
         """Evaluate live equation values through the compiled topology."""
 
@@ -1562,7 +1589,7 @@ class PressureFlowSolver:
             return ExplicitFlowAssignment(
                 equation_id=equation.id,
                 unknown=unknown,
-                evaluate=self._equation_value_reader(equation),
+                evaluate=self._connection_flow_target_reader(equation, unknown),
             )
 
         evaluation = self._component_equation_plans_by_id[equation.owner_id]
@@ -1747,6 +1774,7 @@ class PressureFlowSolver:
     def _evaluate_explicit_flow_stage(
         stage: ExplicitFlowStage,
     ) -> tuple[float, ...]:
+        """Evaluate simultaneous targets while this stage's unknowns are zero."""
         assignments = stage.assignments
         values: list[float | None] = [None] * len(assignments)
         for assignment_index, evaluate in stage.direct_evaluations:
@@ -1764,7 +1792,9 @@ class PressureFlowSolver:
                         "Compiled algebraic equation disappeared at runtime: "
                         f"{equation_id}."
                     )
-                values[assignment_index] = float(equation_values[equation_index])
+                values[assignment_index] = 0.0 - float(
+                    equation_values[equation_index]
+                )
         if any(value is None for value in values):
             raise RuntimeError("Explicit flow evaluation plan returned no value.")
         return tuple(float(value) for value in values)
@@ -1776,9 +1806,15 @@ class PressureFlowSolver:
         """Execute staged flow/force assignments without repeated equations."""
 
         selected = frozenset(variables)
-        for unknown in self.unknowns:
-            if unknown.variable in selected:
-                unknown.write(0.0)
+        reset_unknowns = self._explicit_flow_unknowns_by_variables.get(selected)
+        if reset_unknowns is None:
+            reset_unknowns = tuple(
+                unknown
+                for unknown in self.unknowns
+                if unknown.variable in selected
+            )
+        for unknown in reset_unknowns:
+            unknown.write(0.0)
 
         seeded_ids: set[str] = set()
         plan = self._explicit_flow_plans_by_variables.get(selected)
@@ -1787,14 +1823,7 @@ class PressureFlowSolver:
         for stage in plan:
             assignments = stage.assignments
             values = self._evaluate_explicit_flow_stage(stage)
-            targets = tuple(
-                (
-                    assignment,
-                    assignment.unknown.read() - value,
-                )
-                for assignment, value in zip(assignments, values)
-            )
-            for assignment, target_value in targets:
+            for assignment, target_value in zip(assignments, values):
                 if not isfinite(target_value):
                     continue
                 assignment.unknown.write(target_value)

app/simulation/solvers/algebraic_blocks.py

@@ -779,14 +779,7 @@ class StreamPressureBlockSolver:
                 unknown.write(0.0)
             for stage in self._selected_explicit_flow_plan:
                 values = solver._evaluate_explicit_flow_stage(stage)
-                targets = tuple(
-                    (
-                        assignment,
-                        assignment.unknown.read() - value,
-                    )
-                    for assignment, value in zip(stage.assignments, values)
-                )
-                for assignment, target_value in targets:
+                for assignment, target_value in zip(stage.assignments, values):
                     if isfinite(target_value):
                         assignment.unknown.write(target_value)
                         seeded_equation_ids.add(assignment.equation_id)

tests/test_amesim_pnl0002_pnl0003_component.py

@@ -320,6 +320,38 @@ class AmesimPnl0003ComponentTests(unittest.TestCase):
         self.assertLess(abs(above - below), abs(above) * 0.05)
         self.assertEqual(equal, 0.0)
 
+    def test_exact_repeated_center_flow_inversion_is_cached(self) -> None:
+        pipe = AmesimPnl0003("pnl_3", self.medium)
+        pipe._mass_flow_for_pressure_drop.cache_clear()
+
+        first = pipe._mass_flow_for_pressure_drop(
+            1000.0,
+            density=1.2,
+            temperature=300.0,
+        )
+        after_first = pipe._mass_flow_for_pressure_drop.cache_info()
+        second = pipe._mass_flow_for_pressure_drop(
+            1000.0,
+            density=1.2,
+            temperature=300.0,
+        )
+        after_second = pipe._mass_flow_for_pressure_drop.cache_info()
+        changed_temperature = pipe._mass_flow_for_pressure_drop(
+            1000.0,
+            density=1.2,
+            temperature=400.0,
+        )
+        after_temperature_change = pipe._mass_flow_for_pressure_drop.cache_info()
+
+        self.assertEqual(first, second)
+        self.assertEqual(after_first.misses, 1)
+        self.assertEqual(after_second.hits, after_first.hits + 1)
+        self.assertNotEqual(changed_temperature, second)
+        self.assertEqual(
+            after_temperature_change.misses,
+            after_second.misses + 1,
+        )
+
     def test_pressure_flow_residuals_bind_both_port_pressures_to_states(self) -> None:
         pipe = AmesimPnl0003("pnl_3", self.medium)
         pipe.properties_1()

tests/test_amesim_pnl00r_component.py

@@ -77,6 +77,34 @@ class AmesimPnl00rComponentTests(unittest.TestCase):
         self.assertGreater(pipe.mass_flow(15.3e6 + 0.1, 15.3e6), 0.0)
 
 
+    def test_pressure_drop_inversion_cache_keys_all_property_inputs(self) -> None:
+        pipe = AmesimPnl00r(
+            "pnl_1",
+            self.medium,
+            diam=0.014,
+            le=1.0,
+            rr=0.045 / 14.0,
+        )
+        pipe.port_1.h_outflow = self.medium.specific_enthalpy(300.0)
+        pipe._mass_flow_for_pressure_drop.cache_clear()
+
+        first = pipe.mass_flow(501000.0, 500000.0)
+        after_first = pipe._mass_flow_for_pressure_drop.cache_info()
+        second = pipe.mass_flow(501000.0, 500000.0)
+        after_second = pipe._mass_flow_for_pressure_drop.cache_info()
+        pipe.port_1.h_outflow = self.medium.specific_enthalpy(400.0)
+        third = pipe.mass_flow(501000.0, 500000.0)
+        after_temperature_change = pipe._mass_flow_for_pressure_drop.cache_info()
+
+        self.assertEqual(first, second)
+        self.assertEqual(after_first.misses, 1)
+        self.assertEqual(after_second.hits, after_first.hits + 1)
+        self.assertNotEqual(third, second)
+        self.assertEqual(
+            after_temperature_change.misses,
+            after_second.misses + 1,
+        )
+
     def test_friction_factor_transitions_from_laminar_to_turbulent(self) -> None:
         pipe = AmesimPnl00r("pnl_1", self.medium, rr=1e-5)
 

tests/test_amesim_signal_components.py

@@ -100,6 +100,38 @@ class AmesimSignalComponentTests(unittest.TestCase):
         valve.res.signal = -0.5
         self.assertAlmostEqual(valve.opening, 0.0)
 
+    def test_pnvo001_exact_repeated_flow_characteristics_are_cached(self) -> None:
+        valve = AmesimPnvo001SignalOpening("valve_1", self.medium, opening0=0.25)
+        valve._one_way_flow_characteristics.cache_clear()
+
+        first = valve._one_way_flow_characteristics(
+            upstream_pressure=501000.0,
+            downstream_pressure=500000.0,
+            upstream_temperature=300.0,
+        )
+        after_first = valve._one_way_flow_characteristics.cache_info()
+        second = valve._one_way_flow_characteristics(
+            upstream_pressure=501000.0,
+            downstream_pressure=500000.0,
+            upstream_temperature=300.0,
+        )
+        after_second = valve._one_way_flow_characteristics.cache_info()
+        changed_pressure = valve._one_way_flow_characteristics(
+            upstream_pressure=502000.0,
+            downstream_pressure=500000.0,
+            upstream_temperature=300.0,
+        )
+        after_pressure_change = valve._one_way_flow_characteristics.cache_info()
+
+        self.assertEqual(first, second)
+        self.assertEqual(after_first.misses, 1)
+        self.assertEqual(after_second.hits, after_first.hits + 1)
+        self.assertNotEqual(changed_pressure, second)
+        self.assertEqual(
+            after_pressure_change.misses,
+            after_second.misses + 1,
+        )
+
     def test_signal_resolver_propagates_step_to_valve_input(self) -> None:
         network = SimulationNetwork("signal-smoke")
         step = AmesimStep0("step_1", self.medium, initial=0.0, final=0.75, time=0.1)