Effect of Gender and Body Fitness on the Thermal Sensation of Sleeping Occupants Under Task-Ambient Air Conditioning System

Document Type : Research Article

Authors

1 PhD student, Mechanical engineering, University of Birjand

2 University of Birjand

Abstract

Providing thermal comfort conditions in a sleeping environment can significantly affect the occupants’ health. So, the parameters of the air conditioning system must be properly set to satisfy thermal comfort criteria for persons with different physiological characteristics. In the present study, a task/ambient air conditioning system is modeled and the effect of gender and body mass index on the thermal sensation has been analyzed by an individualized three-node model. Results show that although Gagge standard model predicts pleasant thermal comfort condition, thermal sensation index varies from -0.63 to 0.66 based on the individualized three-node model, and in some cases exceed the thermal comfort region. Moreover, healthy and fat people have a warm sensation in clothed parts of the body and underweight people, especially women, have a cold sensation in bare parts of the body. Also, based on the results of women compared with men, and underweight people compared with overweight people feel colder. By changing body mass index, the thermal sensation index can change up to 0.36, which is very significant in the assessment of thermal comfort.

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