{
  "selected_operating_envelope": {
    "nominal_chamber_radius_mm": 2.525,
    "nominal_probe_radius_mm": 2,
    "minimum_gap_mm": 0.5,
    "maximum_hydraulic_pressure_Pa": 8.173571485867228,
    "flush_time_s": 600,
    "qualified_flush_flow_mm3_s": 4.5,
    "wall_capacity_length_mm": 0.1,
    "wall_exchange_s": 120,
    "inlet_mixed_volume_mm3": 20,
    "sensor_time_constant_s": 30,
    "diffusivity_mm2_s": 0.0005,
    "maximum_old_fraction_at_flush_end": 0.006957725391144411,
    "qualification": "Four independent geometry-tolerance corners plus finer slowest-corner solve. Parameters are explicit synthetic qualification values, not an assertion about unmeasured sensors. The original 90 s desired response is rejected for the slow-retention condition; 600 s is the selected operating wait for this virtual fixture."
  },
  "synthetic": true,
  "tolerance_cases": 162,
  "reference_response_limit_s": 90,
  "response_cases": [
    {
      "case": "ideal_passive",
      "capacity_length_mm": 0,
      "wall_exchange_s": 30,
      "inlet_mixed_volume_mm3": 0,
      "sensor_tau_s": 0,
      "t99_fluid_s": 51.9324096829791,
      "t99_probe_s": 40.90287971799913,
      "t99_sensor_s": 40.90287971799913,
      "t99_inventory_s": 51.9324096829791,
      "t99_outlet_s": 62.191652826675465,
      "maximum_mass_balance_fraction": 1.809382218788134e-15,
      "minimum_fraction": 1.8400110146999359e-25,
      "maximum_fraction": 1.0000000000000022,
      "initial_inventory_mm3": 141.3716694115407,
      "initial_wall_inventory_mm3": 0,
      "elapsed_s": 62.75,
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "sensor_within_90s": true
    },
    {
      "case": "sensor_5s",
      "capacity_length_mm": 0,
      "wall_exchange_s": 30,
      "inlet_mixed_volume_mm3": 0,
      "sensor_tau_s": 5,
      "t99_fluid_s": 51.9324096829791,
      "t99_probe_s": 40.90287971799913,
      "t99_sensor_s": 49.67271812019703,
      "t99_inventory_s": 51.9324096829791,
      "t99_outlet_s": 62.191652826675465,
      "maximum_mass_balance_fraction": 1.809382218788134e-15,
      "minimum_fraction": 1.8400110146999359e-25,
      "maximum_fraction": 1.0000000000000022,
      "initial_inventory_mm3": 141.3716694115407,
      "initial_wall_inventory_mm3": 0,
      "elapsed_s": 62.75,
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "sensor_within_90s": true
    },
    {
      "case": "sensor_30s",
      "capacity_length_mm": 0,
      "wall_exchange_s": 30,
      "inlet_mixed_volume_mm3": 0,
      "sensor_tau_s": 30,
      "t99_fluid_s": 51.9324096829791,
      "t99_probe_s": 40.90287971799913,
      "t99_sensor_s": 156.30605302163076,
      "t99_inventory_s": 51.9324096829791,
      "t99_outlet_s": 62.191652826675465,
      "maximum_mass_balance_fraction": 1.809382218788134e-15,
      "minimum_fraction": 3.241927943590486e-66,
      "maximum_fraction": 1.0000000000000022,
      "initial_inventory_mm3": 141.3716694115407,
      "initial_wall_inventory_mm3": 0,
      "elapsed_s": 204.75,
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "sensor_within_90s": false
    },
    {
      "case": "inlet_mix_20mm3",
      "capacity_length_mm": 0,
      "wall_exchange_s": 30,
      "inlet_mixed_volume_mm3": 20,
      "sensor_tau_s": 5,
      "t99_fluid_s": 57.22342054338996,
      "t99_probe_s": 47.160565933615594,
      "t99_sensor_s": 55.57935394433328,
      "t99_inventory_s": 57.22342054338996,
      "t99_outlet_s": 67.57936908611369,
      "maximum_mass_balance_fraction": 2.8145945625593194e-15,
      "minimum_fraction": 4.0158312651250395e-08,
      "maximum_fraction": 1.0000000000000027,
      "initial_inventory_mm3": 141.3716694115407,
      "initial_wall_inventory_mm3": 0,
      "elapsed_s": 68.5,
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "sensor_within_90s": true
    },
    {
      "case": "wall_fast",
      "capacity_length_mm": 0.02,
      "wall_exchange_s": 30,
      "inlet_mixed_volume_mm3": 0,
      "sensor_tau_s": 5,
      "t99_fluid_s": 91.7222133707212,
      "t99_probe_s": 90.15804176130796,
      "t99_sensor_s": 95.56349576539468,
      "t99_inventory_s": 117.42420934857469,
      "t99_outlet_s": 111.87797034921334,
      "maximum_mass_balance_fraction": 2.4199556424121138e-15,
      "minimum_fraction": 1.4696509861027557e-11,
      "maximum_fraction": 1.0000000000000018,
      "initial_inventory_mm3": 152.68140296446393,
      "initial_wall_inventory_mm3": 11.309733552923255,
      "elapsed_s": 175.0,
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "sensor_within_90s": false
    },
    {
      "case": "wall_slow",
      "capacity_length_mm": 0.1,
      "wall_exchange_s": 120,
      "inlet_mixed_volume_mm3": 20,
      "sensor_tau_s": 30,
      "t99_fluid_s": 297.58464437303104,
      "t99_probe_s": 311.8635993540652,
      "t99_sensor_s": 345.88112886072037,
      "t99_inventory_s": 533.1439862602687,
      "t99_outlet_s": 346.2949238488806,
      "maximum_mass_balance_fraction": 1.1200937544878925e-14,
      "minimum_fraction": 1.0100279454565036e-11,
      "maximum_fraction": 1.0000000000000013,
      "initial_inventory_mm3": 197.92033717615695,
      "initial_wall_inventory_mm3": 56.548667764616276,
      "elapsed_s": 764.75,
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "sensor_within_90s": false
    }
  ],
  "refinement": [
    {
      "nz": 80,
      "nr": 24,
      "dt_s": 0.25,
      "t99_fluid_s": 297.58464437303104,
      "t99_probe_s": 311.8635993540652,
      "t99_sensor_s": 345.88112886072037,
      "t99_inventory_s": 533.1439862602687,
      "maximum_mass_balance_fraction": 1.1200937544878925e-14
    },
    {
      "nz": 160,
      "nr": 48,
      "dt_s": 0.25,
      "t99_fluid_s": 298.1287903396534,
      "t99_probe_s": 312.86343443204106,
      "t99_sensor_s": 346.84256531091,
      "t99_inventory_s": 536.4924344285936,
      "maximum_mass_balance_fraction": 1.809382218788134e-14
    },
    {
      "nz": 160,
      "nr": 48,
      "dt_s": 0.125,
      "t99_fluid_s": 298.0004196465925,
      "t99_probe_s": 312.7264367337851,
      "t99_sensor_s": 346.7075205157091,
      "t99_inventory_s": 536.2637795198026,
      "maximum_mass_balance_fraction": 3.1017980893510866e-14
    }
  ],
  "acceptance": [
    {
      "requirement": "Minimum 0.5 mm physical radial clearance with declared tolerances",
      "outcome": "ORIGINAL FAIL; REVISED PASS",
      "evidence": "Original minimum 0.475 mm. Revised 2.525 mm nominal chamber radius gives minimum 0.500 mm."
    },
    {
      "requirement": "10 Pa hydraulic budget with revised dimensions and input range",
      "outcome": "PASS",
      "evidence": "Worst 8.1736 Pa."
    },
    {
      "requirement": "90 s indicated t99 reference criterion",
      "outcome": "CASE DEPENDENT",
      "evidence": "Passive probe 40.90 s; 30 s sensor lag 156.31 s; slow wall/inlet/sensor case 345.88 s."
    },
    {
      "requirement": "Fluid plus adsorbed inventory conserved",
      "outcome": "PASS",
      "evidence": "Maximum residual 1.12e-14."
    },
    {
      "requirement": "Measured pressure equals fluid resistance without corrections",
      "outcome": "FAIL",
      "evidence": "Declared 0.2 mm tap-height error alone adds 1.9613 Pa."
    },
    {
      "requirement": "Selected 600 s flush on revised geometry at the declared slow-retention condition",
      "outcome": "PASS",
      "evidence": "Maximum old fraction 0.006958; four tolerance corners and finer worst-corner solve."
    }
  ],
  "checks": [
    {
      "id": "original_clearance_failure",
      "description": "Apply declared manufacturing tolerances to original 0.5 mm nominal gap",
      "expected": "minimum gap below 0.5 mm is detected",
      "observed": 0.4750000000000001,
      "passed": true,
      "method": "Full factorial exact annular hydraulic model"
    },
    {
      "id": "allowance_clearance",
      "description": "2.525 mm nominal radius covers +/-0.015 body and +/-0.010 probe radii",
      "expected": "all 81 cases have >= 0.5 mm clearance",
      "observed": 0.5,
      "passed": true,
      "method": "Worst independent radial tolerance sum, no statistical cancellation"
    },
    {
      "id": "allowance_pressure",
      "description": "Unchanged 10 Pa pressure budget for revised nominal radius",
      "expected": "all 81 cases below 10 Pa",
      "observed": 8.173571485867228,
      "passed": true,
      "method": "Exact developed annular Stokes solution"
    },
    {
      "id": "regime",
      "description": "Tolerance/flow/viscosity range remains creeping flow",
      "expected": "max Re < 0.1",
      "observed": 0.08693752322834755,
      "passed": true,
      "method": "Hydraulic diameter 2(b-a)"
    },
    {
      "id": "fem_worst_corner",
      "description": "Check revised worst hydraulic case against independent FEM",
      "expected": "relative error < 1e-5",
      "observed": 7.074845043142375e-09,
      "passed": true,
      "method": "P2/P1 Stokes solve at revised tolerance corner"
    },
    {
      "id": "cad_roundtrip",
      "description": "Revised nominal assembly exports and reimports",
      "expected": "valid body/probe solids; exact fluid volume",
      "observed": [
        {
          "radius_mm": 2.525,
          "fluid_volume_mm3": 149.26492095368508,
          "body_valid": true,
          "probe_valid": true
        }
      ],
      "passed": true,
      "method": "CadQuery solid validity and STEP roundtrip"
    },
    {
      "id": "mass_ideal_passive",
      "description": "Fluid + reversible wall + inlet/outlet conservation in ideal_passive",
      "expected": "max normalized residual < 1e-10",
      "observed": 1.809382218788134e-15,
      "passed": true,
      "method": "Sparse mass-form backward Euler; exchange fluxes cancel in coupled capacities"
    },
    {
      "id": "bounded_ideal_passive",
      "description": "Concentration bounds in ideal_passive",
      "expected": "all fluid/wall concentrations in [0,1] +/- 1e-10",
      "observed": [
        1.8400110146999359e-25,
        1.0000000000000022
      ],
      "passed": true,
      "method": "Every solved state checked"
    },
    {
      "id": "mass_sensor_5s",
      "description": "Fluid + reversible wall + inlet/outlet conservation in sensor_5s",
      "expected": "max normalized residual < 1e-10",
      "observed": 1.809382218788134e-15,
      "passed": true,
      "method": "Sparse mass-form backward Euler; exchange fluxes cancel in coupled capacities"
    },
    {
      "id": "bounded_sensor_5s",
      "description": "Concentration bounds in sensor_5s",
      "expected": "all fluid/wall concentrations in [0,1] +/- 1e-10",
      "observed": [
        1.8400110146999359e-25,
        1.0000000000000022
      ],
      "passed": true,
      "method": "Every solved state checked"
    },
    {
      "id": "mass_sensor_30s",
      "description": "Fluid + reversible wall + inlet/outlet conservation in sensor_30s",
      "expected": "max normalized residual < 1e-10",
      "observed": 1.809382218788134e-15,
      "passed": true,
      "method": "Sparse mass-form backward Euler; exchange fluxes cancel in coupled capacities"
    },
    {
      "id": "bounded_sensor_30s",
      "description": "Concentration bounds in sensor_30s",
      "expected": "all fluid/wall concentrations in [0,1] +/- 1e-10",
      "observed": [
        3.241927943590486e-66,
        1.0000000000000022
      ],
      "passed": true,
      "method": "Every solved state checked"
    },
    {
      "id": "mass_inlet_mix_20mm3",
      "description": "Fluid + reversible wall + inlet/outlet conservation in inlet_mix_20mm3",
      "expected": "max normalized residual < 1e-10",
      "observed": 2.8145945625593194e-15,
      "passed": true,
      "method": "Sparse mass-form backward Euler; exchange fluxes cancel in coupled capacities"
    },
    {
      "id": "bounded_inlet_mix_20mm3",
      "description": "Concentration bounds in inlet_mix_20mm3",
      "expected": "all fluid/wall concentrations in [0,1] +/- 1e-10",
      "observed": [
        4.0158312651250395e-08,
        1.0000000000000027
      ],
      "passed": true,
      "method": "Every solved state checked"
    },
    {
      "id": "mass_wall_fast",
      "description": "Fluid + reversible wall + inlet/outlet conservation in wall_fast",
      "expected": "max normalized residual < 1e-10",
      "observed": 2.4199556424121138e-15,
      "passed": true,
      "method": "Sparse mass-form backward Euler; exchange fluxes cancel in coupled capacities"
    },
    {
      "id": "bounded_wall_fast",
      "description": "Concentration bounds in wall_fast",
      "expected": "all fluid/wall concentrations in [0,1] +/- 1e-10",
      "observed": [
        1.4696509861027557e-11,
        1.0000000000000018
      ],
      "passed": true,
      "method": "Every solved state checked"
    },
    {
      "id": "mass_wall_slow",
      "description": "Fluid + reversible wall + inlet/outlet conservation in wall_slow",
      "expected": "max normalized residual < 1e-10",
      "observed": 1.1200937544878925e-14,
      "passed": true,
      "method": "Sparse mass-form backward Euler; exchange fluxes cancel in coupled capacities"
    },
    {
      "id": "bounded_wall_slow",
      "description": "Concentration bounds in wall_slow",
      "expected": "all fluid/wall concentrations in [0,1] +/- 1e-10",
      "observed": [
        1.0100279454565036e-11,
        1.0000000000000013
      ],
      "passed": true,
      "method": "Every solved state checked"
    },
    {
      "id": "zero_retention_limit",
      "description": "New coupled model reduces to existing passive model",
      "expected": "relative t99 probe error < 1e-10",
      "observed": 0.0,
      "passed": true,
      "method": "Independent public run_transport execution at same mesh and time step"
    },
    {
      "id": "refine_grid",
      "description": "Slow-wall case grid sensitivity",
      "expected": "max t99 change < 0.03",
      "observed": 0.006280570079787662,
      "passed": true,
      "method": "80x24 to 160x48 and 0.25 s to 0.125 s, original threshold retained"
    },
    {
      "id": "refine_timestep",
      "description": "Slow-wall case timestep sensitivity",
      "expected": "max t99 change < 0.03",
      "observed": 0.00043788338034667085,
      "passed": true,
      "method": "80x24 to 160x48 and 0.25 s to 0.125 s, original threshold retained"
    },
    {
      "id": "exchange_benchmark",
      "description": "Isolated fluid/wall exchange approaches conserved equilibrium",
      "expected": "max absolute error < 5e-5",
      "observed": 2.9697706575071425e-05,
      "passed": true,
      "method": "Backward Euler compared with independent exact two-capacity exponential"
    },
    {
      "id": "exchange_mass",
      "description": "Closed two-capacity benchmark conserves initial tracer",
      "expected": "absolute difference < 1e-10",
      "observed": 1.2594369991347776e-12,
      "passed": true,
      "method": "Independent dense update and analytical conserved mass"
    },
    {
      "id": "pressure_correction",
      "description": "Recover known synthetic hydraulic pressure after elevation/zero correction",
      "expected": "absolute mean error < 0.08 Pa",
      "observed": -0.02275547843690351,
      "passed": true,
      "method": "20 seeded readings, known imposed elevation and zero bias"
    },
    {
      "id": "sensor_lag_challenge",
      "description": "30 s sensor time constant changes the reference conclusion",
      "expected": "sensor t99 exceeds 90 s while passive probe t99 is below 90 s",
      "observed": 156.30605302163076,
      "passed": true,
      "method": "Causal first-order sensor driven by the spatial probe average"
    },
    {
      "id": "retention_challenge",
      "description": "Slow wall inventory is retained in response accounting",
      "expected": "inventory t99 exceeds passive-fluid t99",
      "observed": 533.1439862602687,
      "passed": true,
      "method": "Reversible exchange with explicitly assumed capacity and time constant"
    },
    {
      "id": "invalid_inputs",
      "description": "Reject invalid annular hydraulic conditions",
      "expected": "3 invalid conditions rejected",
      "observed": 3,
      "passed": true,
      "method": "Zero gap, negative flow, nonfinite viscosity"
    },
    {
      "id": "selected_flush_decision",
      "description": "Adopted 600 s flush on tolerance-allowance geometry",
      "expected": "all fluid, sensor, inventory and outlet fractions <= 0.01 at four geometry corners",
      "observed": 0.006783047491718452,
      "passed": true,
      "method": "Four new 80x24 runs at 4.5 mm3/s, 0.1 mm wall capacity, 120 s exchange, 20 mm3 inlet and 30 s sensor"
    },
    {
      "id": "selected_flush_refined",
      "description": "Verify the slowest selected corner at finer resolution",
      "expected": "all four fractions <= 0.01 at 600 s",
      "observed": 0.006957725391144411,
      "passed": true,
      "method": "Additional 160x48 run at 0.125 s; full trace retained"
    }
  ]
}