Research on the Ratio between the Convection and Radiation Heat Exchange Amount of the Face and Head of Manikin in the Thermal Comfort Condition

Abstract

In this paper, the radiation heat exchange coefficient of the exposed parts of human body is firstly obtained through pre-experiment, which is used to separate the total output heat exchange amount of the manikin. Then the heat exchange amount of manikin under different airflow organizations of personal ventilation, mixed ventilation and seat ventilation are respectively studied. The value of convection heat exchange and radiation heat exchange of the face and head of human body are compared. And variable conditions are studied for different air temperatures and volumes. It is concluded that when the supply air temperature changes between 22? and 30°C with human body thermally comfortable, the total heat exchange of the face and head changes from 38 W/m2 to 137 W/m2, and the range of the radiation heat exchange amount is 26 W/m2 to 67 W/m2. The convection heat exchange amount changes between 6 W/m2 and 110 W/m2, and the ratio of radiation heat exchange to convection heat exchange changes from 0.5 to 6.7.