{
  "evidence": "BENCH_DESIGN_PREDICTIONS_NO_EXPERIMENTAL_DATA",
  "protocol": {
    "revision": "P3.1 first physical demonstration specification",
    "purpose": "Measure whether cooling increases mass flow through identical duct hardware at matched driving total-pressure head, then account for heat and electrical resources.",
    "geometry_scale": 0.1,
    "air_speed_target_ms": 10.0,
    "cold_reservoir_K": 273.15,
    "initial_ice_mass_kg_assumed": 1.0,
    "ice_fusion_heat_Jkg_reference": 333550,
    "heat_exchanger_UA_WK_assumed": 8.0,
    "maximum_drive_head_difference_Pa": 0.2,
    "maximum_inlet_temperature_difference_K": 0.3,
    "minimum_paired_blocks": 6,
    "dry_air_dewpoint_max_K": 268.15,
    "sequence": "Six or more paired steady blocks, randomised AB/BA order. Same installed heat exchanger and neutral rotor setting. Warm reference and ice-water cold treatment, with drive head controlled rather than assumed from blower voltage.",
    "measurement_channels": [
      "calibrated mass flow",
      "inlet/outlet absolute temperature",
      "ambient pressure",
      "upstream total-pressure head",
      "exchanger differential pressure",
      "source DC voltage and current",
      "bath temperature",
      "melt mass and elapsed time",
      "inlet dewpoint"
    ],
    "success_rule": "First verify control limits and calibration provenance. Report a positive paired mass-flow difference only if its conservative 95 percent interval excludes zero. Separately report cold duty, blower input, and calorimetric uncertainty. This result does not establish net vehicle thrust or self-recharging.",
    "materials": "New unused, traceable duct shells; smooth bonded joints; aluminium heat-exchanger insert isolated from composite where appropriate; transparent low-pressure observation section; rated low-voltage blower and current-limited supply; calibrated instruments. No material performance or prices are assumed from branding.",
    "first_stage_scope": "Ambient-pressure throughflow with an ice-water bath. No liquid nitrogen, oxidiser, sealed freezing-pressure vessel or road deployment is needed for this first test.",
    "limits": [
      "The 1:10 demonstration does not match vehicle Reynolds number or installed moving-road flow.",
      "UA, loss coefficient and predicted signal are design assumptions until measured.",
      "A larger volumetric flow or mass flow is not by itself an energy-efficiency or propulsion result.",
      "Use an independently calibrated flow measurement. Inferring all outputs from the same model would be circular."
    ]
  },
  "predictions": [
    {
      "air_speed_ms": 5.0,
      "reference_mass_flow_kgs": 0.007251972211043733,
      "cold_mass_flow_kgs": 0.007424823531226199,
      "predicted_mass_flow_gain_fraction": 0.023835077569552388,
      "cold_heat_W": 98.20344079677855,
      "ideal_ice_inventory_duration_s": 3396.52050166191,
      "target_per_run_relative_standard_flow_uncertainty_for_2_to_1_signal_to_expanded_uncertainty": 0.0032782354457441126,
      "reservoir": "Finite ice-water phase bath, not N2; no expander electrical output credited."
    },
    {
      "air_speed_ms": 7.5,
      "reference_mass_flow_kgs": 0.010878222058297696,
      "cold_mass_flow_kgs": 0.011078838757482537,
      "predicted_mass_flow_gain_fraction": 0.018442048536030153,
      "cold_heat_W": 114.2782558937946,
      "ideal_ice_inventory_duration_s": 2918.7529805318986,
      "target_per_run_relative_standard_flow_uncertainty_for_2_to_1_signal_to_expanded_uncertainty": 0.0025364875371824826,
      "reservoir": "Finite ice-water phase bath, not N2; no expander electrical output credited."
    },
    {
      "air_speed_ms": 10.0,
      "reference_mass_flow_kgs": 0.01450478837085467,
      "cold_mass_flow_kgs": 0.01472190184373384,
      "predicted_mass_flow_gain_fraction": 0.014968399905470609,
      "cold_heat_W": 123.88818166742567,
      "ideal_ice_inventory_duration_s": 2692.3472078668938,
      "target_per_run_relative_standard_flow_uncertainty_for_2_to_1_signal_to_expanded_uncertainty": 0.0020587278976960375,
      "reservoir": "Finite ice-water phase bath, not N2; no expander electrical output credited."
    },
    {
      "air_speed_ms": 12.5,
      "reference_mass_flow_kgs": 0.01813177659590753,
      "cold_mass_flow_kgs": 0.018359895359998747,
      "predicted_mass_flow_gain_fraction": 0.0125811589881768,
      "cold_heat_W": 130.32446332782624,
      "ideal_ice_inventory_duration_s": 2559.3813431709104,
      "target_per_run_relative_standard_flow_uncertainty_for_2_to_1_signal_to_expanded_uncertainty": 0.0017303909006895614,
      "reservoir": "Finite ice-water phase bath, not N2; no expander electrical output credited."
    },
    {
      "air_speed_ms": 15.0,
      "reference_mass_flow_kgs": 0.021759292145343914,
      "cold_mass_flow_kgs": 0.021995367347428837,
      "predicted_mass_flow_gain_fraction": 0.010849397145276107,
      "cold_heat_W": 134.99012206455166,
      "ideal_ice_inventory_duration_s": 2470.921537803321,
      "target_per_run_relative_standard_flow_uncertainty_for_2_to_1_signal_to_expanded_uncertainty": 0.0014922073646629651,
      "reservoir": "Finite ice-water phase bath, not N2; no expander electrical output credited."
    }
  ],
  "raw_data_rows": 0,
  "first_stage": "Physical hardware not built or instrumented by this software session."
}