代码仓库移植

tests/cryo_tank/conftest.py

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+import os
+import sys
+
+_HERE = os.path.dirname(os.path.abspath(__file__))
+_ROOT = os.path.dirname(os.path.dirname(_HERE))
+sys.path.insert(0, os.path.join(_ROOT, "src"))

tests/cryo_tank/test_heat_leak.py

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+# tests/cryo_tank/test_heat_leak.py
+"""Tests for heat leak models."""
+from cryo_tank.heat_leak import HeatLeakModel, MLIHeatLeak, FoamHeatLeak
+
+
+class TestMLIHeatLeak:
+
+    def test_mli_returns_constant_heat_flux(self):
+        model = MLIHeatLeak(A_total=3.306, q_mli=1.5)
+        Q = model.compute(T_inner=78.0, T_env=300.0)
+        assert abs(Q - 3.306 * 1.5) < 1e-10
+
+    def test_mli_default_q_is_1(self):
+        model = MLIHeatLeak(A_total=3.306)
+        Q = model.compute(T_inner=78.0, T_env=300.0)
+        assert abs(Q - 3.306) < 1e-10
+
+    def test_mli_independent_of_temperature(self):
+        model = MLIHeatLeak(A_total=3.306, q_mli=2.0)
+        Q1 = model.compute(T_inner=78.0, T_env=300.0)
+        Q2 = model.compute(T_inner=80.0, T_env=250.0)
+        assert abs(Q1 - Q2) < 1e-10
+
+
+class TestFoamHeatLeak:
+
+    def test_foam_constant_k(self):
+        model = FoamHeatLeak(A_total=3.306, k_eff=0.03, delta=0.05)
+        Q = model.compute(T_inner=78.0, T_env=300.0)
+        expected = 3.306 * 0.03 * (300.0 - 78.0) / 0.05
+        assert abs(Q - expected) < 1e-6
+
+    def test_foam_callable_k(self):
+        def k_func(T):
+            return 0.01 + 0.0001 * T  # linear k(T)
+
+        model = FoamHeatLeak(A_total=3.306, k_eff=k_func, delta=0.05)
+        Q = model.compute(T_inner=78.0, T_env=300.0)
+        T_mean = (300.0 + 78.0) / 2.0
+        k_at_mean = k_func(T_mean)
+        expected = 3.306 * k_at_mean * (300.0 - 78.0) / 0.05
+        assert abs(Q - expected) < 1e-6
+
+    def test_foam_zero_dT_gives_zero_Q(self):
+        model = FoamHeatLeak(A_total=3.306, k_eff=0.03, delta=0.05)
+        Q = model.compute(T_inner=300.0, T_env=300.0)
+        assert abs(Q) < 1e-10

tests/cryo_tank/test_integration.py

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+# tests/cryo_tank/test_integration.py
+"""Integration tests for the cryogenic tank simulation."""
+import numpy as np
+from cryo_tank.tank_model import CryoTank
+from cryo_tank.heat_leak import MLIHeatLeak
+from cryo_tank.solver import run
+from cryo_tank.config import (
+    V_TOTAL, H_TANK, P_WORKING, T_INIT, ULLAGE_FRACTION,
+    MDOT_IN_LN2, T_IN_LN2, MDOT_OUT_LN2, T_IN_HE,
+    H_CONV_SURFACE, T_ENV, A_TOTAL,
+)
+
+
+def _make_tank(**overrides):
+    """Create a tank with default config, allowing overrides."""
+    kw = dict(
+        V_total=V_TOTAL, H_tank=H_TANK,
+        P_work=P_WORKING,
+        T_init=T_INIT, ullage_fraction=ULLAGE_FRACTION,
+        mdot_in_ln2=MDOT_IN_LN2, T_in_ln2=T_IN_LN2,
+        mdot_out_ln2=MDOT_OUT_LN2,
+        T_in_he=T_IN_HE,
+        h_conv=H_CONV_SURFACE, T_env=T_ENV,
+        heat_leak_model=MLIHeatLeak(A_total=A_TOTAL, q_mli=1.0),
+    )
+    kw.update(overrides)
+    return CryoTank(**kw)
+
+
+class TestMassConservation:
+
+    def test_liquid_mass_change_matches_net_flow(self):
+        """Over a short run, dm_liq should equal (mdot_in - mdot_out) * dt."""
+        tank = _make_tank()
+        history = run(tank, t_end=10.0, max_step=1.0)
+
+        m_liq_0 = history['m_liq'][0]
+        m_liq_f = history['m_liq'][-1]
+        t_f = history['t'][-1]
+
+        expected_dm = (MDOT_IN_LN2 - MDOT_OUT_LN2) * t_f
+        actual_dm = m_liq_f - m_liq_0
+
+        rel_err = abs(actual_dm - expected_dm) / abs(expected_dm)
+        assert rel_err < 1e-6, f"Mass conservation error: rel_err={rel_err:.2e}"
+
+
+class TestSteadyState:
+
+    def test_zero_flow_zero_leak_is_static(self):
+        """With no flow and no heat leak, state should not change."""
+        tank = _make_tank(
+            mdot_in_ln2=0.0,
+            mdot_out_ln2=0.0,
+            h_conv=0.0,
+            heat_leak_model=MLIHeatLeak(A_total=A_TOTAL, q_mli=0.0),
+        )
+        history = run(tank, t_end=100.0, max_step=10.0)
+
+        T_liq = history['T_liq']
+        T_ull = history['T_ull']
+
+        assert abs(T_liq[-1] - T_liq[0]) < 0.01, f"T_liq drifted: {T_liq[0]:.3f} -> {T_liq[-1]:.3f}"
+        assert abs(T_ull[-1] - T_ull[0]) < 0.1, f"T_ull drifted: {T_ull[0]:.3f} -> {T_ull[-1]:.3f}"
+
+
+class TestPhysicalBehavior:
+
+    def test_liquid_level_decreases(self):
+        """With net outflow, liquid level should decrease."""
+        tank = _make_tank()
+        history = run(tank, t_end=60.0, max_step=5.0)
+        assert history['fill_fraction'][-1] < history['fill_fraction'][0]
+
+    def test_he_flow_rate_positive(self):
+        """He should always flow in (pressurization), not out."""
+        tank = _make_tank()
+        history = run(tank, t_end=60.0, max_step=5.0)
+        assert np.all(history['mdot_He'] >= -1e-10)  # allow tiny numerical noise

tests/cryo_tank/test_properties.py

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+# tests/cryo_tank/test_properties.py
+"""Tests for CoolProp property wrappers."""
+import pytest
+import sys
+sys.path.insert(0, "src")
+
+from cryo_tank.properties import (
+    ln2_rho, ln2_h, ln2_u, ln2_T_from_u,
+    n2_vapor_u, n2_sat_pressure,
+    he_u, he_h, he_cp, he_cv,
+)
+from cryo_tank.config import P_WORKING
+
+
+class TestLN2Properties:
+    """Liquid nitrogen properties at P = 0.17 MPa."""
+
+    def test_ln2_density_at_78K(self):
+        rho = ln2_rho(78.0, P_WORKING)
+        assert 800 < rho < 810  # ~803 kg/m3
+
+    def test_ln2_enthalpy_at_77K(self):
+        h = ln2_h(77.0, P_WORKING)
+        assert -130000 < h < -110000  # ~-122695 J/kg
+
+    def test_ln2_internal_energy_at_78K(self):
+        u = ln2_u(78.0, P_WORKING)
+        assert -130000 < u < -110000  # ~-120865 J/kg
+
+    def test_ln2_T_from_u_roundtrip(self):
+        T_orig = 78.0
+        u = ln2_u(T_orig, P_WORKING)
+        T_recovered = ln2_T_from_u(u, P_WORKING)
+        assert abs(T_recovered - T_orig) < 0.01
+
+
+class TestN2VaporProperties:
+    """N2 vapor properties."""
+
+    def test_n2_sat_pressure_at_78K(self):
+        P_sat = n2_sat_pressure(78.0)
+        assert 0.10e6 < P_sat < 0.12e6  # ~0.1093 MPa
+
+    def test_n2_vapor_internal_energy_at_78K(self):
+        u = n2_vapor_u(78.0)
+        assert 50000 < u < 60000  # ~55547 J/kg
+
+
+class TestHeliumProperties:
+    """Helium (ideal gas) properties."""
+
+    def test_he_cp_near_5196(self):
+        cp = he_cp()
+        assert abs(cp - 5196.2) < 10  # monatomic ideal gas
+
+    def test_he_cv_near_3117(self):
+        cv = he_cv()
+        assert abs(cv - 3117.1) < 10
+
+    def test_he_enthalpy_at_100K(self):
+        h = he_h(100.0)
+        # CoolProp gives ~524762 J/kg at 100K
+        assert 500000 < h < 550000
+
+    def test_he_internal_energy_at_78K(self):
+        u = he_u(78.0)
+        assert 200000 < u < 280000  # ~247932 J/kg

tests/cryo_tank/test_tank_model.py

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+# tests/cryo_tank/test_tank_model.py
+"""Tests for CryoTank model."""
+import pytest
+import numpy as np
+from cryo_tank.tank_model import CryoTank
+from cryo_tank.heat_leak import MLIHeatLeak
+from cryo_tank.config import (
+    V_TOTAL, H_TANK, A_CROSS, A_TOTAL, P_WORKING,
+    T_INIT, ULLAGE_FRACTION,
+    MDOT_IN_LN2, T_IN_LN2, MDOT_OUT_LN2, T_IN_HE,
+    H_CONV_SURFACE, T_ENV,
+)
+
+
+def _make_tank():
+    """Create a CryoTank with default config and MLI heat leak."""
+    heat_leak = MLIHeatLeak(A_total=A_TOTAL, q_mli=1.0)
+    return CryoTank(
+        V_total=V_TOTAL, H_tank=H_TANK,
+        P_work=P_WORKING,
+        T_init=T_INIT, ullage_fraction=ULLAGE_FRACTION,
+        mdot_in_ln2=MDOT_IN_LN2, T_in_ln2=T_IN_LN2,
+        mdot_out_ln2=MDOT_OUT_LN2,
+        T_in_he=T_IN_HE,
+        h_conv=H_CONV_SURFACE, T_env=T_ENV,
+        heat_leak_model=heat_leak,
+    )
+
+
+class TestGeometry:
+
+    def test_cross_section_area(self):
+        tank = _make_tank()
+        assert abs(tank.A_cross - 0.8402) < 0.001
+
+    def test_total_surface_area(self):
+        tank = _make_tank()
+        assert abs(tank.A_total - 3.305) < 0.01
+
+    def test_wetted_area_at_70_percent_fill(self):
+        tank = _make_tank()
+        level = 0.7 * H_TANK  # 0.35 m
+        A_wet, A_dry = tank.wetted_areas(level)
+        # A_wet = bottom cap + side * level
+        expected_wet = A_CROSS + np.pi * tank.D * level
+        assert abs(A_wet - expected_wet) < 0.01
+        assert abs(A_wet + A_dry - A_TOTAL) < 0.01
+
+
+class TestInitialState:
+
+    def test_initial_liquid_mass(self):
+        tank = _make_tank()
+        y0 = tank.initial_state()
+        m_liq = y0[0]
+        # rho_LN2(78K, 0.17MPa) ~ 803.3 kg/m3, V_liq = 0.2941 m3
+        assert 235 < m_liq < 237  # ~236.25 kg
+
+    def test_initial_fill_fraction(self):
+        tank = _make_tank()
+        y0 = tank.initial_state()
+        info = tank.derive(y0)
+        assert abs(info['fill_fraction'] - 0.70) < 0.01
+
+    def test_initial_temperatures(self):
+        tank = _make_tank()
+        y0 = tank.initial_state()
+        info = tank.derive(y0)
+        assert abs(info['T_liq'] - T_INIT) < 0.1
+        assert abs(info['T_ull'] - T_INIT) < 1.0
+
+    def test_initial_pressure_components_sum_to_P_working(self):
+        tank = _make_tank()
+        y0 = tank.initial_state()
+        info = tank.derive(y0)
+        P_N2 = info['P_N2']
+        P_He = info['P_He']
+        assert abs(P_N2 + P_He - P_WORKING) / P_WORKING < 1e-6