The Thermal Comfort of Thai Students in University Buildings under Variable Indoor Conditions of Air Conditioned Space

Authors

  • Kodchasorn Hussaro Faculty of Sciene and Technology, Rajamangala University of Technology Rattanakosin, 96 Mu 3 Phuttamonthon Sai 5 Road, Salaya, Phuttamonthon, Nakhon Pathom, 73170
  • Noppanuch Puangmalee
  • Vorakamol Boonyayothin

Keywords:

thermal response time, thermal comfort, air condition room, ASV, PMV

Abstract

The purpose of this research is to determine the thermal response time and temperature range of thermal comfort of Thai students for air-conditioned classrooms survey questionnaires and by the predicted mean vote (PMV) equations, and thereby recommend air-conditioner temperature settings that also saves energy. The students were tested in a 8´9´3 m3 room size with two units of 40,000 Btu/h split-type air conditioners. The air-conditioner temperature setting was varied from 25, 26, 27 and 28 °C and at each temperature setting, the air speed were varied at three levels. The thermal comfort survey questionnaires were based on ASHRAE thermal sensation scale. The results of the thermal sensation vote (TSV) using the questionnaires were as follow; the air temperature at 26±0.5–28±0.5 °C at all average air speed (»0.5-0.9 m/s) were acceptable to the research subjects. Therefore, instead of setting the temperature at 25°C, which is the normal set point in most buildings as recommended by government; the air temperatures can be set higher. It can be between 26–28 °C but with the air speed also increased. These higher air-conditioner temperature settings help reduce energy consumption of air conditioners. The range of neutral temperature (TSV, PMV = 0) from the TSV and PMV equations on air temperature (ta) were 26.7–28.3 °C and 27.7–28.4 °C respectively, which all correspond to thermal comfort acceptability of thermal sensation vote (26±0.5–28±0.5 °C), which is the accepted temperature. In addition, with regards to the relationship of TSV and PMV with air temperature (ta), effective temperature (ET*) and operative temperature (top) at neutral temperature (TSV, PMV = 0), the difference between neutral temperature of TSV and PMV does not exceed 1°C. The PMV equation can predict the thermal comfort of thermal sensation of subjects from the survey when the air conditioner temperature settings are changed from 25°C to 26–28°C, estimated energy savings ranged from 7.67–20.11%. This is approximately 7.30% saving for 1°C increase. The results of this research can be applied to the operation and control of classroom air-conditioners in university buildings to assure thermal comfort of students.

References

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Published

17 January 2019

How to Cite

Hussaro, K., Puangmalee, N., & Boonyayothin, V. (2019). The Thermal Comfort of Thai Students in University Buildings under Variable Indoor Conditions of Air Conditioned Space. Journal of Renewable Energy and Smart Grid Technology, 14(1). Retrieved from https://ph01.tci-thaijo.org/index.php/RAST/article/view/144191

Issue

Vol. 14 No. 1 (2019): January-June

Section

Articles

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