Investigation of Thermal Comfort for Bus Passengers During a Cooling Test Inside a Climatic Chamber

Year 2020, Volume: 23 Issue: 2, 547 - 555, 01.06.2020

Üzeyir Pala

https://doi.org/10.2339/politeknik.608597

Cited By: 1

Abstract

In this current work, thermal comfort for a cooling process inside a bus was described in a combined theoretical and experimental form. The bus was heated to 40 for 7 hours within climatic chamber and AC unit was turned on at the beginning of the test. Temperatures, humidity of air and air velocities were measured at certain points to observe effects of ambient conditions on passengers’ thermal comfort and physiology. Human body was assumed to be one complete piece which is composed of mainly core and skin compartments. Transient Energy Balance Model by Gagge was used for calculation of changes in thermal conditions. Transient heat and mass transfer between bus interior environment and passenger bodies during cooling period were calculated by a mathematical model. Effects of fast transient conditions on either sensible or latent heat transfer from body, temperatures of core and skin, thermal discomfort and thermal sensation which are all factors for human ergonomics were investigated in detail. The aim in this study is to describe a testing and thermal comfort calculation methodology for assessment of thermal comfort of a bus AC system’s cooling performance.

Keywords

Thermal comfort, thermal sensation, bus, cooling period, climatic chamber

Investigation of Thermal Comfort for Bus Passengers during a Cooling Test Inside a Climatic Chamber

Abstract

In this current work, thermal
comfort for a cooling process inside a bus was described in a combined
theoretical and experimental form. The bus was heated to 40 for 7 hours within climatic chamber and AC
unit was turned on at the beginning of the test. Temperatures, humidity of air
and air velocities were measured at certain points to observe effects of
ambient conditions on passengers’ thermal comfort and physiology. Human body
was assumed to be one complete piece which is composed of mainly core and skin compartments.
Transient Energy Balance Model by Gagge was used for calculation of changes in
thermal conditions. Transient heat and mass transfer between bus interior
environment and passenger bodies during cooling period were calculated by a mathematical
model. Effects of fast transient conditions on either sensible or latent heat
transfer from body, temperatures of core and skin, thermal discomfort and thermal
sensation which are all factors for human ergonomics were investigated in
detail. The aim in this study is to describe a testing and thermal comfort
calculation methodology for assessment of thermal comfort of a bus AC system’s cooling
performance.

Keywords

Thermal comfort, thermal sensation, bus, cooling period, climatic chamber

References

• [1] Alahmer A, Mayyas A, Mayyas A.A, Omar M.A, Shan D. “Vehicular thermal comfort models; a comprehensive review”, Applied Thermal Engineering, 31: 995-1002, (2011).[2] Alahmer A, Omar M, Mayyas A.R, Qattawi A. “Analysis of vehicular cabins’ thermal sensation and comfort state, under relative humidity and temperature control, using Berkeley and Fanger models”, Building and Environment, 48: 146-163, (2012).[3] Doherty T.J, Arens E. “Evaluation of the physiological bases of thermal comfort models”, ASHRAE Transaction, 94 (Part 1): 1371-1385, (1988).[4] Gagge A.P, Stolwijk J.A.J, Nishi Y. “An effective temperature scale based on a simple model of human physiological regulatory response”, ASHRAE Transaction, 77(1): 247-262, (1971).[5] Guan Y, Hosni M.H, Jones B.W, Gielda T.P. “Investigation of human thermal comfort under highly transient conditions for automotive applications-Part 1: Experimental design and human subject testing implementation”, ASHRAE Transaction, 109: 885-897, (2003a).[6] Guan Y, Hosni M.H, Jones B.W, Gielda T.P. “Investigation of human thermal comfort under highly transient conditions for automotive applications-Part 2: Thermal sensation modeling”, ASHRAE Transaction, 109: 898-907, (2003b).[7] Jones B.W. “Capabilities and limitations of thermal models for use in thermal comfort models”, Energy Building, 34: 653-659, (2002).[8] Kaynakli O, Unver U, Kilic M. “Simulation of thermal comfort heating and cooling periods in an automobile compartment”, Proceedings of the Automotive Technologies Congress, 24-26 June, Bursa, Turkey: 127-135 (in Turkish), (2002).[9] Kaynakli O, Unver U, Kilic M. “Calculation of thermal comfort zones with the ambient parameters”, Proceedings of the First International Exergy, Energy and Environment Symposium, 13-17 July, Izmir, Turkey: 769-773, (2003a).[10] Kaynakli O, Unver U, Kilic M. “Evaluating thermal environments for sitting and standing posture”, Int. Com. Heat and Mass Transfer, 30 (8): 1179-1188, (2003b).[11] Kaynakli, O., Pulat, E., Kilic, M. “Thermal comfort during heating and cooling periods in an automobile”, Heat and Mass Transfer, 41: 449-458, (2004).[12] Kaynakli O, Kilic M. “An investigation of thermal comfort inside an automobile during the heating period”, Applied Ergonomics, 36: 301-312, (2005).[13] Kilic M, Akyol S.M. “The effects of using different ventilation modes during heating periods of an automobile”, J. of Thermal Science and Technology, 29-1: 25-36, (2009).[14] Pala U, Oz H.R. “An investigation of thermal comfort inside a bus during heating period within a climatic chamber”, Applied Ergonomics, 48: 164-176, (2015).[15] Parsons K.C. “Human Thermal Environments”, Taylor & Francis Ltd., London, UK., (1993).[16] Parsons K.C. “Environmental ergonomics: a review of principles, methods and models”, Applied Ergonomics, 31: 581-594, (2000).[17] Velt K.B, Daanen H.A.M. “Optimal bus temperature for thermal comfort during a cool day”, Applied Ergonomics, 62: 72-76, (2017).