Experimental investigation on the airflow characteristics of an attachment-based personalized ventilation method

Abstract

An attachment-based personalized ventilation method, different from the traditional personalized ventilation methods in mechanisms, is presented in this study to improve the micro-environment surrounding a human body. To identify the airflow characteristics of this personalized ventilation method, field measurements were performed to examine the air distribution via the airflow fields near the body. Three factors on the airflow fields under the personalized ventilation method were analyzed in this study, including the supplied air velocity, the horizontal distance between the air outlet and the human body, the vertical distance between the air outlet and the head of the man. According to the measurements in this study, the results show that the higher the supplied air velocity, the more easily the air attachment is formed. For a certain horizontal distance and a certain vertical distance, air attachment is formed only when the supplied air velocity is greater than a critical supplied air velocity. That critical supplied air velocity is an increasing function of the horizontal distance. When the horizontal distance reaches 0.3 m and regardless of the value of the supplied air velocity, air attachment cannot be formed. In addition, the critical supplied air velocity decreases with the vertical distance. Based on the field measurements, design parameters of the personalized ventilation method are analyzed to achieve optimization. Practical application: A novel personalized ventilation method, which is based on air attachment, is introduced in this paper. Such a personalized ventilation method can be applied to the worktable in factory, office, kitchen, and so on. The experimental results indicate that the novel personalized ventilation method can meet the requirements of fresh air in the breathing zone and provide an acceptable thermal comfort for occupants under certain conditions.