Abstract
The present work is dedicated to the analysis of dry heat exchanges as measured by a thermal manikin placed in still air. We believe that the understanding of some fundamental aspects governing fluid flow and heat transfer around three-dimensional bodies such as human beings deserves appropriate attention. This should be of great significance for improving physiological models concerned with thermal exposures. The potential interest of such work can be directed towards quite distinct targets such as working conditions, sports, the military, or healthcare personnel and patients. In the present study, we made use of a climate chamber and an articulated thermal manikin of the Pernille type, with 16 body parts. The most common occidental postures (standing, sitting and lying) were studied. In order to separate heat losses due to radiation and convection, the radiative heat losses of the manikin were significantly reduced by means of a shiny aluminium coating, which was carefully applied to the artificial skin. The air temperature within the test chamber was varied between 13°C and 29°C. The corresponding mean differences between the skin and the operative temperatures changed from 3.8°C up to 15.8°C. The whole-body heat transfer coefficients by radiation and convection for both standing and sitting postures are in good agreement with those in the published literature. The lying posture appears to be more efficient for losing heat by convection. This is confirmed when the heat losses of each individual part are considered. The proposed correlations for the whole body suggest that natural convection is mainly laminar.
Similar content being viewed by others
References
American Society of Heating Refrigerating and Air-Conditioning Engineers (ASHRAE) (2001) Thermal comfort. In: ASHRAE fundamentals handbook, chap 8. ASHRAE, Atlanta, Ga.
Borges C, Brites G, Gaspar A, Quintela D, Costa J (2002) Analysis of thermal plumes generated by a seated person, a thermal manikin and a dummy. In: Proceedings of ROOMVENT 2002, Copenhagen, Denmark, 8–11 September 2002
De Dear R, Arens E, Hui Z, Oguro M (1997) Convective and radiative heat transfer coefficients for individual human body segments. Int J Biometeorol 40:141–156
Fanger P (1972) Thermal comfort. McGraw Hill, New York
House J, Tipton M (2002) Using skin temperature gradients or skin heat flux measurements to determine thresholds of vasoconstriction and vasodilatation. Eur J Appl Physiol 88:141–145
ISO 7730 (1994) Moderate thermal environments–determination of PMV and PPD indices and specification of the conditions for thermal comfort. ISO Standard, Geneva
Murakami S (2002) CFD study on the micro-climate around the human body with inhalation and exhalation. In: Proceedings of ROOMVENT 2002, Copenhagen, Denmark, 8–11 September 2002
Oguro M, Arens E, de Dear R, Zhang H, Katayama T (2002) Convective heat transfer coefficients and clothing insulations for parts of the clothed human body under calm conditions. J Archit Plann Environ Eng 561:31–39.
Quintela D, Gaspar A, Mendes V, Silva M (1998) Evaluation of thermal environments in office buildings and schools. A Portuguese case study. ROOMVENT’98, the 6th international conference on air distribution in rooms, 14–17 June 1998, Stockholm, Sweden
Quintela D, Gaspar A, Raimundo (2000) A Development of local heating systems for thermal comfort and energy savings in buildings. Union Internationale Pour Applications De l’Electricite international conference, 1–4 November 2000, Lisbon, Portugal
Stolwijk J (1970) Mathematical model of thermoregulation. In: Hardy J (ed) Physical and behavioral temperature regulation. Thomas, Springfield, Ill., pp 703–721
Tanabe S, Arens E, Bauman F, Zhang H, Madsen T (1994) Evaluating thermal environments by using a thermal manikin with controlled skin surface temperature. ASHRAE Transactions 100:39–48
Thellier F (1994) The analysis of thermal comfort requirements through the simulation of an occupied building. Ergonomics 37:817–825
Acknowledgements
The authors are grateful for fruitful discussions with Dr. F. Thellier and Professor F. Monchoux from LESETH, within the co-operative project No. 606 B4 between Toulouse and Coimbra Universities.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Quintela, D., Gaspar, A. & Borges, C. Analysis of sensible heat exchanges from a thermal manikin. Eur J Appl Physiol 92, 663–668 (2004). https://doi.org/10.1007/s00421-004-1132-3
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00421-004-1132-3