Experimental investigation of personalized ventilation effects on temperature, velocity, and draught discomfort distribution in an office

Document Type : Research Article

Authors

1 University of Birjand

2 Department of Mechanical Engineering, University of Birjand, Iran

3 Department of Mechanical Engineering, Tarbiat Modares University

Abstract

In this research, it has been tried to experimentally investigate the effect of a personalized ventilation system on airflow and temperature distribution in a room for two inlet air temperatures (24 and 32°C) and two different arrangements of the inlet diffusers (desk-mounted and under-desk air terminals). The results showed that the penetration depth of heat and momentum due to the inlet diffusers were not the same; So that the effect of inlet diffusers’ temperature on the room temperature distribution is significant up to a distance of about 60 cm. However, the effect of inlet velocity is noticeable up to a distance of about 110 cm. Therefore, the occupants’ thermal sensations up to the distance of about one meter from the inlet diffusers will be affected by the inlet conditions. Also, the results indicated that the draught discomfort along with the diffusers’ centerline is significant to a distance of about 180 cm. Based on the results, the air velocity and turbulence intensity are the two main factors in determining the draught discomfort in the personalized ventilation system and due to the rapid thermal mixing of inlet air with the room air, the effect of inlet temperature on the draught discomfort is not significant.

Keywords

Main Subjects

References

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Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 7
October 2021
Pages 4397-4410

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