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Vehicles in FASTSim

A vehicle model is a structured representation of the physical parameters of a real-world vehicle. FASTSim’s modeling framework has been exercised over a wide variety of on-road vehicles, from passenger cars, to two-wheelers, to medium- and heavy-duty vocational vehicles.

For guidance on creation of custom vehicle models, see Modeling a Vehicle.

FASTSim’s vehicle model is a hierarchy of components:

Vehicle

  • Total vehicle mass* mass_kilograms

  • Auxiliary power load pwr_aux_base_watts

    • constant value for whole drive cycle

    • e.g. 600 W

Powertrain type (pt_type)

Powertrain-specific vehicle parameters.

One of:

  • ConventionalVehicle / Conv

  • HybridElectricVehicle / HEV

  • PlugInHybridElectricVehicle / PHEV

  • BatteryElectricVehicle / BEV

ConventionalVehicle

  • Alternator efficiency alt_eff

    • Applies to auxiliary power load

  • Powertrain control pt_cntrl

    • Used for enabling/configuring auto start-stop

  • Decel fuel cutoff (DFCO) control dfco_cntrl

  • Conventional powertrain mass* mass_kilograms

Fuel storage (tank) fs

  • Maximum power output pwr_out_max_watts

  • Time to peak power (linear ramp for power limitation) pwr_ramp_lag_seconds

  • Energy capacity energy_capacity_joules

  • Fuel storage mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • Fuel storage specific energy specific_energy_joules_per_kilogram

Fuel converter (e.g. engine) fc

  • Maximum power output pwr_out_max_watts

  • Initial power output pwr_out_max_init_watts

  • Time to peak power (linear ramp for power limitation) pwr_ramp_lag_seconds

  • Efficiency eff_interp_from_pwr_out

  • Idle fuel power pwr_idle_fuel_watts

    • Fuel converter power will only drop below this value if it is off

  • FC mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • FC specific power specific_pwr_watts_per_kilogram

  • FC thermal model thrml

    None

    Disable FC thermal model

    Examples:

    YAML
    thrml: None
    Python dictionary
    {
  ...
   'thrml': 'None',
  ...
}
    FuelConverterThermal

    Lumped thermal capacitance FC model

    • Fuel converter thermal capacitance heat_capacitance_joules_per_kelvin

    • Characteristic length length_for_convection_meters

    • Heat transfer coefficient to ambient when vehicle is stopped htc_to_amb_stop_watts_per_square_meter_kelvin

    • Heat transfer coefficient between adiabatic flame temperature and fuel converter temperature conductance_from_comb_watts_per_kelvin

    • Max fraction of combustion heat that goes to fuel converter thermal mass max_frac_from_comb

    • Temperature at which thermostat starts to open tstat_te_sto_kelvin

    • Temperature delta over which thermostat is partially open tstat_te_delta_kelvin

    • Thermostat model tstat_interp

    • Ratio of active heat rejection from radiator to passive heat rejection radiator_effectiveness

      • Always greater than 1

    • Impact of temperature on efficiency fc_eff_model

    Examples:

    YAML
    thrml:
  FuelConverterThermal:
    heat_capacitance_joules_per_kelvin: 72132.17831078888
    length_for_convection_meters: 0.5427107485587468
    htc_to_amb_stop_watts_per_square_meter_kelvin: 60.7820169953251
    conductance_from_comb_watts_per_kelvin: 2178.965385428629
    max_frac_from_comb: 0.5
    tstat_te_sto_kelvin: 358.15
    tstat_te_delta_kelvin: 5.0
    tstat_interp:
      data:
        grid:
          - [85.0, 90.0]
        values:
          - 0.0
          - 1.0
      strategy: Linear
      extrapolate: Clamp
    radiator_effectiveness: 168.06311964877182
    fc_eff_model:
      Exponential:
        offset: 320.1873803210462
        lag: 24.998774179607892
        minimum: 0.1927168135089094
    state:
      i: 0
      te_adiabatic_kelvin: 3153.8328742654194
      temperature_kelvin: 295.15
      tstat_open_frac: 0.0
      htc_to_amb_watts_per_square_meter_kelvin: 0.0
      pwr_thrml_to_amb_watts: 0.0
      energy_thrml_to_amb_joules: 0.0
      eff_coeff: 1.0
      pwr_thrml_fc_to_cab_watts: 0.0
      energy_thrml_fc_to_cab_joules: 0.0
      pwr_fuel_as_heat_watts: 0.0
      energy_fuel_as_heat_joules: 0.0
      pwr_thrml_to_tm_watts: 0.0
      energy_thrml_to_tm_joules: 0.0
    history:
      i: []
      te_adiabatic_kelvin: []
      temperature_kelvin: []
      tstat_open_frac: []
      htc_to_amb_watts_per_square_meter_kelvin: []
      pwr_thrml_to_amb_watts: []
      energy_thrml_to_amb_joules: []
      eff_coeff: []
      pwr_thrml_fc_to_cab_watts: []
      energy_thrml_fc_to_cab_joules: []
      pwr_fuel_as_heat_watts: []
      energy_fuel_as_heat_joules: []
      pwr_thrml_to_tm_watts: []
      energy_thrml_to_tm_joules: []
    save_interval: 1
    Python dictionary
    {
  ...
  'thrml': {
    'FuelConverterThermal': {
      'heat_capacitance_joules_per_kelvin': 72132.17831078888,
      'length_for_convection_meters': 0.5427107485587468,
      'htc_to_amb_stop_watts_per_square_meter_kelvin': 60.7820169953251,
      'conductance_from_comb_watts_per_kelvin': 2178.965385428629,
      'max_frac_from_comb': 0.5,
      'tstat_te_sto_kelvin': 358.15,
      'tstat_te_delta_kelvin': 5.0,
      'tstat_interp': {
        'data': {
           'grid': [[85.0, 90.0]],
           'values': [0.0, 1.0]
         },
        'strategy': 'Linear',
        'extrapolate': 'Clamp'
      },
      'radiator_effectiveness': 168.06311964877182,
      'fc_eff_model': {
        'Exponential': {
          'offset': 320.1873803210462,
          'lag': 24.998774179607892,
          'minimum': 0.1927168135089094
        }
      },
      'state': {
        'i': 0,
        'te_adiabatic_kelvin': 3153.8328742654194,
        'temperature_kelvin': 295.15,
        'tstat_open_frac': 0.0,
        'htc_to_amb_watts_per_square_meter_kelvin': 0.0,
        'pwr_thrml_to_amb_watts': 0.0,
        'energy_thrml_to_amb_joules': 0.0,
        'eff_coeff': 1.0,
        'pwr_thrml_fc_to_cab_watts': 0.0,
        'energy_thrml_fc_to_cab_joules': 0.0,
        'pwr_fuel_as_heat_watts': 0.0,
        'energy_fuel_as_heat_joules': 0.0,
        'pwr_thrml_to_tm_watts': 0.0,
        'energy_thrml_to_tm_joules': 0.0
      },
      'history': {
        'i': [],
        'te_adiabatic_kelvin': [],
        'temperature_kelvin': [],
        'tstat_open_frac': [],
        'htc_to_amb_watts_per_square_meter_kelvin': [],
        'pwr_thrml_to_amb_watts': [],
        'energy_thrml_to_amb_joules': [],
        'eff_coeff': [],
        'pwr_thrml_fc_to_cab_watts': [],
        'energy_thrml_fc_to_cab_joules': [],
        'pwr_fuel_as_heat_watts': [],
        'energy_fuel_as_heat_joules': [],
        'pwr_thrml_to_tm_watts': [],
        'energy_thrml_to_tm_joules': []
      },
      'save_interval': 1
    }
  },
  ...
}
Transmission transmission

  • Efficiency eff_interp

  • Transmission mass* mass

HybridElectricVehicle & PlugInHybridElectricVehicle

  • Powertrain control pt_cntrl

    • Used for enabling/configuring auto start-stop

  • Decel fuel cutoff (DFCO) control dfco_cntrl

  • Auxiliary power load control aux_cntrl

    • Configures whether auxiliary power should come from res or fc first

  • HEV/PHEV-specific simulation parameters sim_params

  • HEV/PHEV powertrain mass* mass_kilograms

Reversible Energy Storage (traction battery) res

  • Maximum power output pwr_out_max_watts

  • Energy capacity energy_capacity_joules

  • Maximum power output pwr_out_max_watts

  • Efficiency eff_interp

    • One of:

      • Constant(float)

      • CRate

      • CRateSOCTemperature

      • CRateTemperature

      • CRateSOC

  • Minimum state of charge min_soc

  • Maximum state of charge max_soc

  • RES mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • RES specific energy specific_energy_joules_per_kilogram

  • RES thermal model thrml

    None

    Disable RES thermal model

    Examples:

    YAML
    thrml: None
    Python dictionary
    {
  ...
   'thrml': 'None',
  ...
}
    RESLumpedThermal

    Lumped thermal capacitance RES model

    • Thermal capacitance heat_capacitance_joules_per_kelvin

    • Heat transfer coefficient from RES to ambient conductance_to_amb_watts_per_kelvin

    • Heat transfer coefficient from RES to cabin conductance_to_cab_watts_per_kelvin

    Examples:

    YAML
    thrml:
  RESLumpedThermal:
    heat_capacitance_joules_per_kelvin: 200000.0
    conductance_to_amb_watts_per_kelvin: 0.1
    conductance_to_cab_watts_per_kelvin: 0.5
    state:
      i: 0
      temperature_kelvin: 295.15
      temp_prev_kelvin: 295.15
      pwr_thrml_from_cabin_watts: 0.0
      energy_thrml_from_cabin_joules: 0.0
      pwr_thrml_from_amb_watts: 0.0
      energy_thrml_from_amb_joules: 0.0
      pwr_thrml_hvac_to_res_watts: 0.0
      energy_thrml_hvac_to_res_joules: 0.0
      pwr_thrml_loss_watts: 0.0
      energy_thrml_loss_joules: 0.0
    history:
      i: []
      temperature_kelvin: []
      temp_prev_kelvin: []
      pwr_thrml_from_cabin_watts: []
      energy_thrml_from_cabin_joules: []
      pwr_thrml_from_amb_watts: []
      energy_thrml_from_amb_joules: []
      pwr_thrml_hvac_to_res_watts: []
      energy_thrml_hvac_to_res_joules: []
      pwr_thrml_loss_watts: []
      energy_thrml_loss_joules: []
    save_interval: 1
    Python dictionary
    {
  ...
  'thrml': {
    'RESLumpedThermal': {
      'heat_capacitance_joules_per_kelvin': 200000.0,
      'conductance_to_amb_watts_per_kelvin': 0.1,
      'conductance_to_cab_watts_per_kelvin': 0.5,
      'state': {
        'i': 0,
        'temperature_kelvin': 295.15,
        'temp_prev_kelvin': 295.15,
        'pwr_thrml_from_cabin_watts': 0.0,
        'energy_thrml_from_cabin_joules': 0.0,
        'pwr_thrml_from_amb_watts': 0.0,
        'energy_thrml_from_amb_joules': 0.0,
        'pwr_thrml_hvac_to_res_watts': 0.0,
        'energy_thrml_hvac_to_res_joules': 0.0,
        'pwr_thrml_loss_watts': 0.0,
        'energy_thrml_loss_joules': 0.0
      },
      'history': {
        'i': [],
        'temperature_kelvin': [],
        'temp_prev_kelvin': [],
        'pwr_thrml_from_cabin_watts': [],
        'energy_thrml_from_cabin_joules': [],
        'pwr_thrml_from_amb_watts': [],
        'energy_thrml_from_amb_joules': [],
        'pwr_thrml_hvac_to_res_watts': [],
        'energy_thrml_hvac_to_res_joules': [],
        'pwr_thrml_loss_watts': [],
        'energy_thrml_loss_joules': []
      },
      'save_interval': 1
    }
  },
  ...
}
Fuel storage (tank) fs

  • Maximum power output pwr_out_max_watts

  • Time to peak power (linear ramp for power limitation) pwr_ramp_lag_seconds

  • Energy capacity energy_capacity_joules

  • Fuel storage mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • Fuel storage specific energy specific_energy_joules_per_kilogram

Fuel converter (e.g. engine) fc

  • Maximum power output pwr_out_max_watts

  • Initial power output pwr_out_max_init_watts

  • Time to peak power (linear ramp for power limitation) pwr_ramp_lag_seconds

  • Efficiency eff_interp_from_pwr_out

  • Idle fuel power pwr_idle_fuel_watts

    • Fuel converter power will only drop below this value if it is off

  • FC mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • FC specific power specific_pwr_watts_per_kilogram

  • FC thermal model thrml

    None

    Disable FC thermal model

    Examples:

    YAML
    thrml: None
    Python dictionary
    {
  ...
  'thrml': 'None',
  ...
}
    FuelConverterThermal

    Lumped thermal capacitance FC model

    • Fuel converter thermal capacitance heat_capacitance_joules_per_kelvin

    • Characteristic length length_for_convection_meters

    • Heat transfer coefficient to ambient when vehicle is stopped htc_to_amb_stop_watts_per_square_meter_kelvin

    • Heat transfer coefficient between adiabatic flame temperature and fuel converter temperature conductance_from_comb_watts_per_kelvin

    • Max fraction of combustion heat that goes to fuel converter thermal mass max_frac_from_comb

    • Temperature at which thermostat starts to open tstat_te_sto_kelvin

    • Temperature delta over which thermostat is partially open tstat_te_delta_kelvin

    • Thermostat model tstat_interp

    • Ratio of active heat rejection from radiator to passive heat rejection radiator_effectiveness

      • Always greater than 1

    • Impact of temperature on efficiency fc_eff_model

    Examples:

    YAML
    thrml:
  FuelConverterThermal:
    heat_capacitance_joules_per_kelvin: 72132.17831078888
    length_for_convection_meters: 0.5427107485587468
    htc_to_amb_stop_watts_per_square_meter_kelvin: 60.7820169953251
    conductance_from_comb_watts_per_kelvin: 2178.965385428629
    max_frac_from_comb: 0.5
    tstat_te_sto_kelvin: 358.15
    tstat_te_delta_kelvin: 5.0
    tstat_interp:
      data:
        grid:
          - [85.0, 90.0]
        values:
          - 0.0
          - 1.0
      strategy: Linear
      extrapolate: Clamp
    radiator_effectiveness: 168.06311964877182
    fc_eff_model:
      Exponential:
        offset: 320.1873803210462
        lag: 24.998774179607892
        minimum: 0.1927168135089094
    state:
      i: 0
      te_adiabatic_kelvin: 3153.8328742654194
      temperature_kelvin: 295.15
      tstat_open_frac: 0.0
      htc_to_amb_watts_per_square_meter_kelvin: 0.0
      pwr_thrml_to_amb_watts: 0.0
      energy_thrml_to_amb_joules: 0.0
      eff_coeff: 1.0
      pwr_thrml_fc_to_cab_watts: 0.0
      energy_thrml_fc_to_cab_joules: 0.0
      pwr_fuel_as_heat_watts: 0.0
      energy_fuel_as_heat_joules: 0.0
      pwr_thrml_to_tm_watts: 0.0
      energy_thrml_to_tm_joules: 0.0
    history:
      i: []
      te_adiabatic_kelvin: []
      temperature_kelvin: []
      tstat_open_frac: []
      htc_to_amb_watts_per_square_meter_kelvin: []
      pwr_thrml_to_amb_watts: []
      energy_thrml_to_amb_joules: []
      eff_coeff: []
      pwr_thrml_fc_to_cab_watts: []
      energy_thrml_fc_to_cab_joules: []
      pwr_fuel_as_heat_watts: []
      energy_fuel_as_heat_joules: []
      pwr_thrml_to_tm_watts: []
      energy_thrml_to_tm_joules: []
    save_interval: 1
    Python dictionary
    {
  ...
  'thrml': {
    'FuelConverterThermal': {
      'heat_capacitance_joules_per_kelvin': 72132.17831078888,
      'length_for_convection_meters': 0.5427107485587468,
      'htc_to_amb_stop_watts_per_square_meter_kelvin': 60.7820169953251,
      'conductance_from_comb_watts_per_kelvin': 2178.965385428629,
      'max_frac_from_comb': 0.5,
      'tstat_te_sto_kelvin': 358.15,
      'tstat_te_delta_kelvin': 5.0,
      'tstat_interp': {
        'data': {
           'grid': [[85.0, 90.0]],
           'values': [0.0, 1.0]
         },
        'strategy': 'Linear',
        'extrapolate': 'Clamp'
      },
      'radiator_effectiveness': 168.06311964877182,
      'fc_eff_model': {
        'Exponential': {
          'offset': 320.1873803210462,
          'lag': 24.998774179607892,
          'minimum': 0.1927168135089094
        }
      },
      'state': {
        'i': 0,
        'te_adiabatic_kelvin': 3153.8328742654194,
        'temperature_kelvin': 295.15,
        'tstat_open_frac': 0.0,
        'htc_to_amb_watts_per_square_meter_kelvin': 0.0,
        'pwr_thrml_to_amb_watts': 0.0,
        'energy_thrml_to_amb_joules': 0.0,
        'eff_coeff': 1.0,
        'pwr_thrml_fc_to_cab_watts': 0.0,
        'energy_thrml_fc_to_cab_joules': 0.0,
        'pwr_fuel_as_heat_watts': 0.0,
        'energy_fuel_as_heat_joules': 0.0,
        'pwr_thrml_to_tm_watts': 0.0,
        'energy_thrml_to_tm_joules': 0.0
      },
      'history': {
        'i': [],
        'te_adiabatic_kelvin': [],
        'temperature_kelvin': [],
        'tstat_open_frac': [],
        'htc_to_amb_watts_per_square_meter_kelvin': [],
        'pwr_thrml_to_amb_watts': [],
        'energy_thrml_to_amb_joules': [],
        'eff_coeff': [],
        'pwr_thrml_fc_to_cab_watts': [],
        'energy_thrml_fc_to_cab_joules': [],
        'pwr_fuel_as_heat_watts': [],
        'energy_fuel_as_heat_joules': [],
        'pwr_thrml_to_tm_watts': [],
        'energy_thrml_to_tm_joules': []
      },
      'save_interval': 1
    }
  },
  ...
}
Electric Machine (motor) em

Electric machine / motor model

  • eff_interp_achieved

  • eff_interp_at_max_input

  • Maximum output power pwr_out_max_watts

  • EM mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • EM specific power specific_pwr_watts_per_kilogram

Transmission transmission

  • Efficiency eff_interp

  • Transmission mass* mass

BatteryElectricVehicle

  • BEV powertrain mass* mass_kilograms

Reversible Energy Storage (traction battery) res

  • Maximum power output pwr_out_max_watts

  • Energy capacity energy_capacity_joules

  • Maximum power output pwr_out_max_watts

  • Efficiency eff_interp

    • One of:

      • Constant(float)

      • CRate

      • CRateSOCTemperature

      • CRateTemperature

      • CRateSOC

  • Minimum state of charge min_soc

  • Maximum state of charge max_soc

  • RES mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • RES specific energy specific_energy_joules_per_kilogram

  • RES thermal model thrml

    None

    Disable RES thermal model

    Examples:

    YAML
    thrml: None
    Python dictionary
    {
  ...
   'thrml': 'None',
  ...
}
    RESLumpedThermal

    Lumped thermal capacitance RES model

    • Thermal capacitance heat_capacitance_joules_per_kelvin

    • Heat transfer coefficient from RES to ambient conductance_to_amb_watts_per_kelvin

    • Heat transfer coefficient from RES to cabin conductance_to_cab_watts_per_kelvin

    Examples:

    YAML
    thrml:
  RESLumpedThermal:
    heat_capacitance_joules_per_kelvin: 200000.0
    conductance_to_amb_watts_per_kelvin: 0.1
    conductance_to_cab_watts_per_kelvin: 0.5
    state:
      i: 0
      temperature_kelvin: 295.15
      temp_prev_kelvin: 295.15
      pwr_thrml_from_cabin_watts: 0.0
      energy_thrml_from_cabin_joules: 0.0
      pwr_thrml_from_amb_watts: 0.0
      energy_thrml_from_amb_joules: 0.0
      pwr_thrml_hvac_to_res_watts: 0.0
      energy_thrml_hvac_to_res_joules: 0.0
      pwr_thrml_loss_watts: 0.0
      energy_thrml_loss_joules: 0.0
    history:
      i: []
      temperature_kelvin: []
      temp_prev_kelvin: []
      pwr_thrml_from_cabin_watts: []
      energy_thrml_from_cabin_joules: []
      pwr_thrml_from_amb_watts: []
      energy_thrml_from_amb_joules: []
      pwr_thrml_hvac_to_res_watts: []
      energy_thrml_hvac_to_res_joules: []
      pwr_thrml_loss_watts: []
      energy_thrml_loss_joules: []
    save_interval: 1
    Python dictionary
    {
  ...
  'thrml': {
    'RESLumpedThermal': {
      'heat_capacitance_joules_per_kelvin': 200000.0,
      'conductance_to_amb_watts_per_kelvin': 0.1,
      'conductance_to_cab_watts_per_kelvin': 0.5,
      'state': {
        'i': 0,
        'temperature_kelvin': 295.15,
        'temp_prev_kelvin': 295.15,
        'pwr_thrml_from_cabin_watts': 0.0,
        'energy_thrml_from_cabin_joules': 0.0,
        'pwr_thrml_from_amb_watts': 0.0,
        'energy_thrml_from_amb_joules': 0.0,
        'pwr_thrml_hvac_to_res_watts': 0.0,
        'energy_thrml_hvac_to_res_joules': 0.0,
        'pwr_thrml_loss_watts': 0.0,
        'energy_thrml_loss_joules': 0.0
      },
      'history': {
        'i': [],
        'temperature_kelvin': [],
        'temp_prev_kelvin': [],
        'pwr_thrml_from_cabin_watts': [],
        'energy_thrml_from_cabin_joules': [],
        'pwr_thrml_from_amb_watts': [],
        'energy_thrml_from_amb_joules': [],
        'pwr_thrml_hvac_to_res_watts': [],
        'energy_thrml_hvac_to_res_joules': [],
        'pwr_thrml_loss_watts': [],
        'energy_thrml_loss_joules': []
      },
      'save_interval': 1
    }
  },
  ...
}
Electric Machine (motor) em

Electric machine / motor model

  • eff_interp_achieved

  • eff_interp_at_max_input

  • Maximum output power pwr_out_max_watts

  • EM mass* mass_kilograms

    • Optional component-level mass

    • Alternatively:

      • EM specific power specific_pwr_watts_per_kilogram

Transmission transmission

  • Efficiency eff_interp

  • Transmission mass* mass

Chassis (chassis)

  • Aerodynamic drag coefficient drag_coef

  • Vehicle frontal area frontal_area_square_meters

  • Wheel rolling resistance coefficient wheel_rr_coef

  • Number of wheels num_wheels

  • Wheel radius wheel_radius_meters

  • Vehicle drivetrain configuration drive_type

    • “FWD”, “RWD”, “AWD”, or “FourWD”

    • Only affects traction limitation / tire slip calculation, so if not applicable just choose FWD

  • Height of vehicle center of gravity cg_height_meters

    • Only affects traction limitation / tire slip calculation, safe to leave at ~0.6 m for most vehicles

  • Wheel friction coefficient wheel_fric_coef

    • Only affects traction limitation / tire slip calculation, safe to leave at ~0.7 for most vehicles

  • Vehicle wheelbase wheel_base_meters

  • Alternatively set with a tire code tire_code e.g. “225/60R18”

  • Component-level masses*:

    • Chassis mass mass_kilograms

    • Alternatively:

      • Glider mass glider_mass_kilograms

      • Cargo mass cargo_mass_kilograms

Cabin thermal model (cabin)

Models cabin temperature, heat can flow between cabin and:

  • surroundings/ambient conditions

  • fuel converter (e.g. engine)

  • reversible energy storage (traction battery)

None

Disable cabin thermal model

Examples:

YAML
cabin: None
Python dictionary
{
  ...
  'cabin': 'None',
  ...
}
LumpedCabin

Lumped thermal capacitance cabin model

  • cab_shell_htc_to_amb_watts_per_square_meter_kelvin

    • Inverse of cabin shell thermal resistance

  • cab_htc_to_amb_stop_watts_per_square_meter_kelvin

    • Heat transfer coefficient from cabin outer surface to ambient when vehicle is stopped

  • heat_capacitance_joules_per_kelvin

    • Cabin thermal capacitance

  • length_meters

    • Cabin length (modeled as a flat plate)

  • width_meters

    • Cabin width (modeled as a flat plate)

Examples:

YAML
cabin:
  LumpedCabin:
    cab_shell_htc_to_amb_watts_per_square_meter_kelvin: 10.111988385072632
    cab_htc_to_amb_stop_watts_per_square_meter_kelvin: 153.22457193685642
    heat_capacitance_joules_per_kelvin: 250000
    length_meters: 3.302 # 130 in. estimate
    width_meters: 2.02184 # vehicle width without mirrors
    state:
      i: 0
      temperature_kelvin: 295.15
      temp_prev_kelvin: 295.15
      pwr_thrml_from_hvac_watts: 0.0
      energy_thrml_from_hvac_joules: 0.0
      pwr_thrml_from_amb_watts: 0.0
      energy_thrml_from_amb_joules: 0.0
      pwr_thrml_to_res_watts: 0.0
      energy_thrml_to_res_joules: 0.0
      reynolds_for_plate: 0.0
    history:
      i: []
      temperature_kelvin: []
      temp_prev_kelvin: []
      pwr_thrml_from_hvac_watts: []
      energy_thrml_from_hvac_joules: []
      pwr_thrml_from_amb_watts: []
      energy_thrml_from_amb_joules: []
      pwr_thrml_to_res_watts: []
      energy_thrml_to_res_joules: []
      reynolds_for_plate: []
    save_interval: 1
Python dictionary
{
  ...
  'cabin': {'LumpedCabin': {'cab_shell_htc_to_amb_watts_per_square_meter_kelvin': 10.111988385072632,
    'cab_htc_to_amb_stop_watts_per_square_meter_kelvin': 153.22457193685642,
    'heat_capacitance_joules_per_kelvin': 250000.0,
    'length_meters': 3.302,
    'width_meters': 2.02184,
    'state': {'i': 0,
      'temperature_kelvin': 295.15,
      'temp_prev_kelvin': 295.15,
      'pwr_thrml_from_hvac_watts': 0.0,
      'energy_thrml_from_hvac_joules': 0.0,
      'pwr_thrml_from_amb_watts': 0.0,
      'energy_thrml_from_amb_joules': 0.0,
      'pwr_thrml_to_res_watts': 0.0,
      'energy_thrml_to_res_joules': 0.0,
      'reynolds_for_plate': 0.0},
    'history': {'i': [],
      'temperature_kelvin': [],
      'temp_prev_kelvin': [],
      'pwr_thrml_from_hvac_watts': [],
      'energy_thrml_from_hvac_joules': [],
      'pwr_thrml_from_amb_watts': [],
      'energy_thrml_from_amb_joules': [],
      'pwr_thrml_to_res_watts': [],
      'energy_thrml_to_res_joules': [],
      'reynolds_for_plate': []},
    'save_interval': 1}},
  ...
}
HVAC thermal model (hvac)

Models HVAC behavior and related heat flow.

None

Disable HVAC thermal model

Examples:

YAML
hvac: None
Python dictionary
{
  ...
  'hvac': 'None',
  ...
}
LumpedCabin

HVAC system for lumped thermal capacitance cabin model.

Examples

YAML
hvac:
  LumpedCabin:
    te_set_kelvin: 295.15
    te_deadband_kelvin: 0.5
    p_watts_per_kelvin: 489.34499608760177
    i: 36.77964270414921
    pwr_i_max_watts: 10000.0
    d: 5.0
    pwr_thrml_max_watts: 15000.0
    frac_of_ideal_cop: 0.0778419513178728
    heat_source: FuelConverter
    pwr_aux_for_hvac_max_watts: 8000.0
    state:
      i: 0
      pwr_p_watts: 0.0
      energy_p_joules: 0.0
      pwr_i_watts: 0.0
      energy_i_joules: 0.0
      pwr_d_watts: 0.0
      energy_d_joules: 0.0
      cop: ~
      pwr_aux_for_hvac_watts: 0.0
      energy_aux_for_hvac_joules: 0.0
      pwr_thrml_hvac_to_cabin_watts: 0.0
      energy_thrml_hvac_to_cabin_joules: 0.0
      pwr_thrml_fc_to_cabin_watts: 0.0
      energy_thrml_fc_to_cabin_joules: 0.0
    history:
      i: []
      pwr_p_watts: []
      energy_p_joules: []
      pwr_i_watts: []
      energy_i_joules: []
      pwr_d_watts: []
      energy_d_joules: []
      cop: []
      pwr_aux_for_hvac_watts: []
      energy_aux_for_hvac_joules: []
      pwr_thrml_hvac_to_cabin_watts: []
      energy_thrml_hvac_to_cabin_joules: []
      pwr_thrml_fc_to_cabin_watts: []
      energy_thrml_fc_to_cabin_joules: []
    save_interval: 1
Python dictionary
{
  ...
  'hvac': {'LumpedCabin': {'te_set_kelvin': 295.15,
    'te_deadband_kelvin': 0.5,
    'p_watts_per_kelvin': 489.34499608760177,
    'i': 36.77964270414921,
    'pwr_i_max_watts': 10000.0,
    'd': 5.0,
    'pwr_thrml_max_watts': 15000.0,
    'frac_of_ideal_cop': 0.0778419513178728,
    'heat_source': 'FuelConverter',
    'pwr_aux_for_hvac_max_watts': 8000.0,
    'state': {'i': 0,
      'pwr_p_watts': 0.0,
      'energy_p_joules': 0.0,
      'pwr_i_watts': 0.0,
      'energy_i_joules': 0.0,
      'pwr_d_watts': 0.0,
      'energy_d_joules': 0.0,
      'cop': None,
      'pwr_aux_for_hvac_watts': 0.0,
      'energy_aux_for_hvac_joules': 0.0,
      'pwr_thrml_hvac_to_cabin_watts': 0.0,
      'energy_thrml_hvac_to_cabin_joules': 0.0,
      'pwr_thrml_fc_to_cabin_watts': 0.0,
      'energy_thrml_fc_to_cabin_joules': 0.0},
    'history': {'i': [],
      'pwr_p_watts': [],
      'energy_p_joules': [],
      'pwr_i_watts': [],
      'energy_i_joules': [],
      'pwr_d_watts': [],
      'energy_d_joules': [],
      'cop': [],
      'pwr_aux_for_hvac_watts': [],
      'energy_aux_for_hvac_joules': [],
      'pwr_thrml_hvac_to_cabin_watts': [],
      'energy_thrml_hvac_to_cabin_joules': [],
      'pwr_thrml_fc_to_cabin_watts': [],
      'energy_thrml_fc_to_cabin_joules': []},
    'save_interval': 1}},
  ...
}
LumpedCabinAndRES

HVAC system for lumped thermal capacitance cabin model and Reversible Energy Storage (traction battery) thermal model

Examples

YAML
hvac:
  LumpedCabinAndRES:
    te_set_cab_kelvin: 295.15
    te_deadband_cab_kelvin: 0.5
    p_cabin_watts_per_kelvin: 881.6321317014631
    i_cabin: 34.0671708520381
    pwr_i_max_cabin_watts: 15000.0
    d_cabin: 10.0
    te_set_res_kelvin: 295.15
    te_deadband_res_kelvin: 15.0
    p_res_watts_per_kelvin: 7.776638335865715
    i_res: 1.014641941728727
    pwr_i_max_res_watts: 15000.0
    d_res: 10.0
    pwr_thrml_max_watts: 15000.0
    frac_of_ideal_cop: 0.1672948274768393
    cabin_heat_source: ResistanceHeater
    res_heat_source: ResistanceHeater
    res_cooling_source: HVAC
    pwr_aux_for_hvac_cab_max_watts: 5000.0
    pwr_aux_for_hvac_res_max_watts: 5000.0
    save_interval: 1
Python dictionary
{
  ...
  'hvac': {
    'LumpedCabinAndRES': {
      'te_set_cab_kelvin': 295.15,
      'te_deadband_cab_kelvin': 0.5,
      'p_cabin_watts_per_kelvin': 881.6321317014631,
      'i_cabin': 34.0671708520381,
      'pwr_i_max_cabin_watts': 15000.0,
      'd_cabin': 10.0,
      'te_set_res_kelvin': 295.15,
      'te_deadband_res_kelvin': 15.0,
      'p_res_watts_per_kelvin': 7.776638335865715,
      'i_res': 1.014641941728727,
      'pwr_i_max_res_watts': 15000.0,
      'd_res': 10.0,
      'pwr_thrml_max_watts': 15000.0,
      'frac_of_ideal_cop': 0.1672948274768393,
      'cabin_heat_source': 'ResistanceHeater',
      'res_heat_source': 'ResistanceHeater',
      'res_cooling_source': 'HVAC',
      'pwr_aux_for_hvac_cab_max_watts': 5000.0,
      'pwr_aux_for_hvac_res_max_watts': 5000.0,
      'state': {
        'i': 0,
        'pwr_p_cab_watts': 0.0,
        'energy_p_cab_joules': 0.0,
        'pwr_i_cab_watts': 0.0,
        'energy_i_cab_joules': 0.0,
        'pwr_d_cab_watts': 0.0,
        'energy_d_cab_joules': 0.0,
        'pwr_p_res_watts': 0.0,
        'energy_p_res_joules': 0.0,
        'pwr_i_res_watts': 0.0,
        'energy_i_res_joules': 0.0,
        'pwr_d_res_watts': 0.0,
        'energy_d_res_joules': 0.0,
        'cop': None,
        'te_ref_kelvin': None,
        'pwr_aux_for_cab_hvac_req_watts': 0.0,
        'pwr_thrml_to_cab_req_watts': 0.0,
        'pwr_aux_for_res_hvac_req_watts': 0.0,
        'pwr_thrml_to_res_req_watts': 0.0,
        'pwr_aux_for_cab_hvac_watts': 0.0,
        'energy_aux_for_cab_hvac_joules': 0.0,
        'pwr_aux_for_res_hvac_watts': 0.0,
        'energy_aux_for_res_hvac_joules': 0.0,
        'pwr_thrml_hvac_to_cabin_watts': 0.0,
        'energy_thrml_hvac_to_cabin_joules': 0.0,
        'pwr_thrml_fc_to_cabin_watts': 0.0,
        'energy_thrml_fc_to_cabin_joules': 0.0,
        'pwr_thrml_hvac_to_res_watts': 0.0,
        'energy_thrml_hvac_to_res_joules': 0.0,
        'te_ref_component': 'None',
        'cabin_mode': 'Inactive',
        'res_mode': 'Inactive'
      },
      'history': {
        'i': [],
        'pwr_p_cab_watts': [],
        'energy_p_cab_joules': [],
        'pwr_i_cab_watts': [],
        'energy_i_cab_joules': [],
        'pwr_d_cab_watts': [],
        'energy_d_cab_joules': [],
        'pwr_p_res_watts': [],
        'energy_p_res_joules': [],
        'pwr_i_res_watts': [],
        'energy_i_res_joules': [],
        'pwr_d_res_watts': [],
        'energy_d_res_joules': [],
        'cop': [],
        'te_ref_kelvin': [],
        'pwr_aux_for_cab_hvac_req_watts': [],
        'pwr_thrml_to_cab_req_watts': [],
        'pwr_aux_for_res_hvac_req_watts': [],
        'pwr_thrml_to_res_req_watts': [],
        'pwr_aux_for_cab_hvac_watts': [],
        'energy_aux_for_cab_hvac_joules': [],
        'pwr_aux_for_res_hvac_watts': [],
        'energy_aux_for_res_hvac_joules': [],
        'pwr_thrml_hvac_to_cabin_watts': [],
        'energy_thrml_hvac_to_cabin_joules': [],
        'pwr_thrml_fc_to_cabin_watts': [],
        'energy_thrml_fc_to_cabin_joules': [],
        'pwr_thrml_hvac_to_res_watts': [],
        'energy_thrml_hvac_to_res_joules': [],
        'te_ref_component': [],
        'cabin_mode': [],
        'res_mode': []
      },
      'save_interval': 1
    }
  },
  ...
}

*Mass can be set for the entire vehicle at the outermost level of the hierarchy (mass_kilograms), or on each component and calculated automatically during initialization.

For guidance on creation of custom vehicle models, see Modeling a Vehicle.

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