Simulation of cabin climatic conditions is becoming increasingly important as a complement to wind tunnel and field testing to help achieve improved thermal comfort while reducing vehicle development time and cost. Delphi developed the Virtual Thermal Comfort Engineering (VTCE) process to explore different climate control strategies as they relate to occupant thermal comfort in a quick and inexpensive manner. The comfort model has the ability to predict the local thermal comfort level of an occupant in a highly non-uniform thermal environment as a function of air temperature, surrounding surface temperatures, air velocity, humidity, direct solar flux, as well as the level of activity and clothing type of each individual. In the present study, test data have been used to validate VTCE for a Sport Utility Vehicle (SUV) cabin environment and used VTCE to perform sensitivity studies of various vehicle cabin environments on the occupant thermal comfort, including discharge temperature, breath level temperature and air velocity, solar intensity and solar angles. The sensitivity of the occupant thermal comfort, in the present study, is based on an OEM's comfort scale for both summer and winter rides. VTCE is suitable for the evaluation of heat load and occupant thermal comfort in a vehicle cabin. This simulation tool allows the rapid assessment of various parameters with respect to thermal comfort during the early stage of vehicle development. The following conclusions are made from the present study: i) Delphi VTCE (Virtual Thermal Comfort Engineering) can be used to simulate Equivalent Homogeneous Temperature (EHT) values for various cabin thermal environments. These values, in turn, can be used to predict the occupant thermal comfort in terms of the OEM's comfort ratings. ii) The present full 3-D flow and thermal analysis takes into account the geometrical configuration of the passenger compartment, including glazing surfaces and pertinent physical and thermal properties of the enclosure. iii) Accurate predictions of airflow and temperature distributions in the cabin are crucial to the success of VTCE. The full 3-D CFD analysis of soak and cool-down simulations demonstrated excellent agreement with experimental data for a full-size SUV. iv) The present thermal comfort model for VTCE was validated using an OEM's thermal comfort ratings for summer and winter ride tests. v) VTCE can be used to explore different climate control strategies in the early stage of vehicle development without the need for time-consuming vehicle level tests.
A case study of occupant thermal comfort in a cabin using virtual thermal comfort engineering
Fallstudie der Klimabehaglichkeit der Insassen in einer Fahrzeugkabine unter Verwendung eines virtuellen Klimabehaglichkeits-Engineering
2005
16 Seiten, 26 Bilder, 16 Quellen
Aufsatz (Konferenz)
Englisch
A Sensitivity Study of Occupant Thermal Comfort in a Cabin Using Virtual Thermal Comfort Engineering
SAE Technical Papers | 2005
|British Library Conference Proceedings | 2005
|Virtual thermal comfort engineering
Kraftfahrwesen | 2001
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