Virtual Thermal Comfort Engineering

Simulation of passenger compartment 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 Harrison Thermal Systems has collaborated with the University of California, Berkeley to develop the capability of predicting occupant thermal comfort to support automotive climate control systems. At the core of this Virtual Thermal Comfort Engineering (VTCE) technique is a model of the human thermal regulatory system based on Stolwijk’s model but with several enhancements. Our model uses 16 body segments and each segment is modeled as four body layers (core, muscle, fat, and skin tissues) and a clothing layer. The comfort model has the ability to predict 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. VTCE takes into account the geometrical configuration of the passenger compartment including glazing surfaces, pertinent physical and thermal properties of the enclosure with particular emphasis on glass properties. Use of Virtual Thermal Comfort Engineering (VTCE) will allow for exploration of different climate control strategies as they relate to human thermal comfort in a quick and inexpensive manner.

[1]  Joachim Currle,et al.  Numerical Simulation of the Flow in a Passenger Compartment and Evaluation of the Thermal Comfort of the Occupants , 1997 .

[2]  Tetsumi Horikoshi.  Evaluating thermal environments by using a thermal manikin with controlled skin surface temperature. Tanabe, S., Arens, E. A., Bauman, F. S., Zhang, H., Madsen, T. L.: ASHRAE Transactions, 100(1): 39/48, 1994(Abstracts of foreign literatures) , 1996 .

[3]  S. M. Horvath,et al.  Variability of physiological parameters of unacclimatized males during a two—hour cold stress of 5°C , 1970 .

[4]  Joachim Currle,et al.  Numerical Study of the Influence of Air Vent Area and Air Mass Flux on the Thermal Comfort of Car Occupants , 2000 .

[5]  Vincenzo Corrado,et al.  Routine for the calculation of angle factors between human body and car driver's cabin , 1995 .

[6]  Edward Arens,et al.  Indoor Environmental Quality ( IEQ ) Title A model of human physiology and comfort for assessing complex thermal environments , 2001 .

[7]  Mingyu Wang,et al.  Air Conditioning System Head Pressure Spike During Vehicle Acceleration , 2000 .

[8]  A. P. Gagge,et al.  An Effective Temperature Scale Based on a Simple Model of Human Physiological Regulatiry Response , 1972 .

[9]  J. Hearle,et al.  Physical Properties of Textile Fibres , 1962 .

[10]  Taeyoung Han,et al.  Effects of HVAC Design Parameters on Passenger Thermal Comfort , 1992 .

[11]  J D Hardy,et al.  Partitional calorimetric studies of man during exposures to thermal transients. , 1966, Journal of applied physiology.

[12]  J D Hardy,et al.  Partitional calorimetric studies of responses of man to thermal transients. , 1966, Journal of applied physiology.

[13]  Stefan Larsson,et al.  Standard procedures for assessing vehicle climate with a thermal manikin , 1989 .

[14]  J. Michalsky.  The Astronomical Almanac's algorithm for approximate solar position (1950 - 2050). , 1988 .

[15]  Shinichi Tanabe,et al.  Indoor Environmental Quality ( IEQ ) Title Evaluating thermal environments by using a thermal manikin with controlled skin surface temperature , 2006 .

[16]  Chao-Hsin Lin,et al.  An Experimental and Computational Study of Cooling in a Simplified GM-10 Passenger Compartment , 1991 .

[17]  Ingvar Holmér,et al.  Evaluation of vehicle climate with a thermal manikin. The relationship between human temperature experience and local heat loss , 1990 .

[18]  E. Arens,et al.  Convective and radiative heat transfer coefficients for individual human body segments , 1997, International journal of biometeorology.