PHEM

The PHEM simulation tool was developt by Graz University of Technology (TU Graz) in cooperation with Forschungsgesellschaft für Verbrennungskraftmaschinen und Thermodynamik (FVT). PHEM is a detailed model for 1Hz simulation of single motor vehicles and vehicle fleets.

Model Features

  • Vehicle longitudinal dynamics simulation using a "backward" approach
  • Engine emission behaviour characterised by "emission maps" via engine speed and power
  • Additional model elements for exhaust aftertreatment simulation (e.g. SCR, NSC), electrified powertrains (HEV, PHEV, EV) and emission behaviour in transient conditions
  • Calculation of cold-start extra emissions as well as tire and brake wear PM and PN
  • Evaluation of measured driving cycles with regard to savings potential (fuel and emissions)
  • Time resolution: 1 Hz
  • HBEFA "average-vehicles" are provided in the corresponding PHEM data package
  • Main model output: fuel consumption, CO 2 and pollutant emissions
  • Interface to micro-scale traffic models (e.g. VISSIM, Aimsun)

Typical Model Applications

  • Used for elaboration of HBEFA emission factors for passenger cars, light commercial vehicles and heavy duty vehicles. Implementation of two-wheelers in progress for HBEFA.
  • Using HBEFA "average vehicles" for generation of emission factors for special local conditions (user defined data on driving cycles, road gradient, ambient conditions, special fleet mix …) 
    Example: Comparison of vehicle emissions for speed limit 30 km/h vs. 50 km/h from measured velocity trajectories
  • Research and engineering tool
    Example: simulation of thermal conditions in the exhaust system for layout of waste heat recovery systems
  • Link with micro-scale traffic models (e.g. VISSIM, Aimsun)
    Examples: Traffic light optimisation, high quality air quality modelling
  • Academic use (teaching)

The sofware is distributed as executable code and a license file to run PHEM on two computers. PHEM has a huge data base for different cars, HDV and LDV from which also input fiels for the "average" vehicle categories were elaborated. Data files can be provided for the following vehicle categories:

  • Passenger Cars (diesel, gasoline, EURO 0 to EURO 6d)
  • Light Duty Vehicles (diesel, gasoline, EURO 0 to EURO 6)
  • Heavy Duty Vehicles (diesel, EURO 0 to EURO VI, split into weight categories)
  • Buses
  • Coaches
  • Motorcycles (gasoline, EURO 0 to EURO 6, split into capacity categories)

Further details and prices can be found in our product flyer.

For further details and questions on obtaining a license please contact us directly.


  1. ITnA
  2. Research
  3. Research areas
  4. Emissions
  5. PHEM