{"physical_measurements":0,"mass_kg":2790.7896,"mass_ledger":[{"component":"Reference vehicle mass","mass_kg":1995.0},{"component":"Inherited duct, fan, control and chassis hardware allowance","mass_kg":270.0},{"component":"Updated 216s11p battery, including 35% overhead","mass_kg":227.7396},{"component":"Inherited later-stage machine and control allowances","mass_kg":55.0},{"component":"Floor machinery beyond original six equivalent stages","mass_kg":100.0},{"component":"Active-camber mechanisms and hydraulic supply","mass_kg":60.0},{"component":"Extended upper-vent gimbal allowance","mass_kg":4.0},{"component":"Replacement open-nitrogen thermal-stage dry hardware","mass_kg":55.0},{"component":"Maximum liquid nitrogen carried","mass_kg":6.0},{"component":"Gas/hold-up mass margin","mass_kg":0.05},{"component":"Uprated traction path installation allowance","mass_kg":18.0}],"mass_status":"Design allowances, not weighed production parts. Inherited lump allowances have not been reduced or reallocated as a performance benefit.","thermal_dry_mass_budget_kg":{"hot boiler/reheater cores and headers":8.0,"insulated liquid vessel and mounts":8.0,"liquid pump and drive":5.0,"two expansion stages and bearings":8.0,"generator and rectification":10.0,"exhaust extraction blower and bypass":4.0,"piping and insulation":6.0,"valves, instrumentation and supports":6.0},"thermal_preparation":{"initial_liquid_kg":6.0,"cold_metal_heat_J":162671.53593242654,"preparation_s":39.2907495786745,"preparation_heat_leak_J":589.3612436801195,"preparation_boiloff_kg":0.8196813568757365,"available_liquid_after_preparation_kg":5.180318643124264,"reversible_liquid_preparation_floor_J":4450117.254184179,"startup_DC_J":2000.0,"hot_metal_initial_K":293.15,"hot_metal_preheated_before_driving":false},"heat_exchanger_geometry_screen":[{"core":"boiler","width_m":0.35,"flow_length_m":0.3,"hot_channels":50,"hot_channel_gap_m":0.004,"hot_exchange_area_m2":10.5,"hot_free_area_m2":0.07,"hot_velocity_ms_at_1kg_s_700K":28.329632371083143,"hydraulic_diameter_m":0.007909604519774011,"Re_at_assumed_3p3e_5_Pa_s":3424.0712206813896,"pressure_loss_Pa_at_1kg_s_700K_screen":519.80805081517,"foil_mass_kg_at_100micrometre":4.431000000000001,"hot_HTC_W_m2K_screen":85.7255541444963,"hot_UA_with_1p4_effective_fin_factor_W_K_screen":1260.1656459240955,"correlation_limit":"Smooth-duct turbulent correlation near transition; it is a preliminary sizing estimate, not a qualified plate-fin map."},{"core":"reheater","width_m":0.35,"flow_length_m":0.15,"hot_channels":30,"hot_channel_gap_m":0.004,"hot_exchange_area_m2":3.15,"hot_free_area_m2":0.042,"hot_velocity_ms_at_1kg_s_700K":47.216053951805236,"hydraulic_diameter_m":0.007909604519774011,"Re_at_assumed_3p3e_5_Pa_s":5706.785367802316,"pressure_loss_Pa_at_1kg_s_700K_screen":950.1439096193631,"foil_mass_kg_at_100micrometre":1.3293000000000001,"hot_HTC_W_m2K_screen":128.9998783776072,"hot_UA_with_1p4_effective_fin_factor_W_K_screen":568.8894636452477,"correlation_limit":"Smooth-duct turbulent correlation near transition; it is a preliminary sizing estimate, not a qualified plate-fin map."}],"combined_hot_pressure_loss_Pa_screen":1469.951960434533,"combined_hot_pressure_loss_requirement_Pa":1500.0,"hot_pressure_geometry_gate":true,"selected_control_changes":{"floor_series_stages":7,"floor_parallel_paths":3,"launch_floor_target_N":30000.0,"braking_floor_target_below_150kmh_N":29500.0,"braking_floor_target_above_250kmh_N":19000.0,"traction_wheel_power_ceiling_W":280000.0,"shared_DC_consumer_limit_W":310000.0,"brake_power_scheduling_fraction":0.98,"retained_brake_gain_uncertainty_factor":1.15,"retained_mechanical_brake_ceiling_W":3000000.0},"unqualified_interfaces":["Installed motor torque/speed/gearing, rotational inertia and transient losses must satisfy the effective wheel-power envelope; catalogue peak power alone does not establish it.","An added parallel battery string changes the power and mass envelope, not the declared 10 MJ chemical or 8 MJ DC exchange windows.","New fan stages and the uprated electrical path need detailed packaging and their own structure/cooling qualification. The earlier P4.0 swept suspension clearances do not qualify these added assemblies.","The lumped heat-exchanger transient closes energy and exergy but does not resolve two-phase distribution or local thermal stress.","Combined core pressure loss, UA and dry mass must be achieved simultaneously. Correlation screens do not establish an installed map.","Smooth-road seal performance remains a required map; the road/fault simulations do not include measured road roughness."],"sources":[{"title":"CoolProp nitrogen thermophysical model","url":"https://coolprop.org/fluid_properties/fluids/Nitrogen.html","use":"Real-fluid nitrogen enthalpy, entropy, saturation and density."},{"title":"Special Metals alloy 625 bulletin","url":"https://www.specialmetals.com/documents/technical-bulletins/inconel/inconel-alloy-625.pdf","use":"Typical hot-metal heat capacity and density; not pressure or fatigue qualification."},{"title":"NIST cryogenic material properties","url":"https://trc.nist.gov/cryogenics/materials/316Stainless/316Stainless_rev.htm","use":"316 stainless cold-metal heat capacity; carried from the P3.8 property model."},{"title":"EMRAX 348 V1.7","url":"https://emrax.com/wp-content/uploads/2025/06/EMRAX-348_datasheet_v1.7.pdf","use":"Size and winding-specific rating reference only. It is not a qualified installed 280 kW wheel-drive selection."},{"title":"Cascadia CM350SiC","url":"https://www.cascadiamotion.com/cm-350sic","use":"Voltage/current/power class reference. Motor winding, gearing and coolant integration need a matched design."}]}