feat: integrate AMESim media models and editor UI

app/simulation/core/medium.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
+from typing import Protocol
 
 
 @dataclass(frozen=True)
@@ -12,6 +13,53 @@ class ThermodynamicProperties:
     h: float
 
 
+class GasMedium(Protocol):
+    """Thermodynamic contract required by pneumatic components.
+
+    ``IdealGasMedium`` is the default implementation.  Keeping the component
+    boundary structural allows a later helium/Peng-Robinson implementation to
+    be registered without changing every AMESim component constructor.
+    """
+
+    name: str
+    R_gas: float
+    cp_ref: float
+    T_ref: float
+
+    @property
+    def cv(self) -> float: ...
+
+    @property
+    def gamma(self) -> float: ...
+
+    def cp_at_temperature(self, T: float) -> float: ...
+
+    def cv_at_temperature(self, T: float) -> float: ...
+
+    def density(self, p: float, T: float) -> float: ...
+
+    def dynamic_viscosity(self, T: float) -> float: ...
+
+    def specific_internal_energy(self, T: float) -> float: ...
+
+    def specific_enthalpy(self, T: float) -> float: ...
+
+    def temperature_from_internal_energy(self, u: float) -> float: ...
+
+    def temperature_from_enthalpy(self, h: float) -> float: ...
+
+    def temperature_from_mass_internal_energy(self, m: float, U: float) -> float: ...
+
+    def pressure(self, m: float, T: float, V: float) -> float: ...
+
+    def properties_from_mU(
+        self,
+        m: float,
+        U: float,
+        V: float,
+    ) -> ThermodynamicProperties: ...
+
+
 @dataclass(frozen=True)
 class IdealGasMedium:
     """Temperature-dependent ideal-gas air approximation.
@@ -27,6 +75,9 @@ class IdealGasMedium:
     cp_ref: float = 1005.0
     T_ref: float = 300.0
     cp_slope: float = 0.0
+    viscosity_ref: float = 1.82e-5
+    viscosity_T_ref: float = 293.15
+    sutherland_constant: float = 110.4
 
     @property
     def cv(self) -> float:
@@ -45,6 +96,18 @@ class IdealGasMedium:
     def density(self, p: float, T: float) -> float:
         return p / (self.R_gas * T)
 
+    def dynamic_viscosity(self, T: float) -> float:
+        """Return dynamic viscosity using the default air Sutherland law."""
+
+        if T <= 0.0:
+            raise ValueError("Temperature must be positive.")
+        return (
+            self.viscosity_ref
+            * (T / self.viscosity_T_ref) ** 1.5
+            * (self.viscosity_T_ref + self.sutherland_constant)
+            / (T + self.sutherland_constant)
+        )
+
     def specific_internal_energy(self, T: float) -> float:
         delta_T = T - self.T_ref
         return (
@@ -77,6 +140,22 @@ class IdealGasMedium:
         delta_T = positive_root if abs(positive_root) <= abs(negative_root) else negative_root
         return self.T_ref + delta_T
 
+    def temperature_from_enthalpy(self, h: float) -> float:
+        reference_enthalpy = self.cp_ref * self.T_ref
+        delta_h = h - reference_enthalpy
+
+        if abs(self.cp_slope) <= 1e-15:
+            return self.T_ref + delta_h / self.cp_ref
+
+        a = 0.5 * self.cp_slope
+        b = self.cp_ref
+        c = -delta_h
+        discriminant = max(b * b - 4.0 * a * c, 0.0)
+        positive_root = (-b + discriminant**0.5) / (2.0 * a)
+        negative_root = (-b - discriminant**0.5) / (2.0 * a)
+        delta_T = positive_root if abs(positive_root) <= abs(negative_root) else negative_root
+        return self.T_ref + delta_T
+
     def temperature_from_mass_internal_energy(self, m: float, U: float) -> float:
         if m <= 0.0:
             raise ValueError("Mass must stay positive when recovering temperature.")