Determination of the Acceptable Room Temperature Range for Local Cooling

Abstract

Determination of the acceptable room temperature range is a key problem in satisfactory design of local cooling for energy savings. At the room temperatures ranging from neutral to warm, three sensitive body parts-the face, chest and back-were each exposed to local cooling airflow, where temperatures were 22, 25 and 28°C. Thirty randomly-selected male subjects, dressed in shorts, were exposed to each condition for 30 minutes. Data were collected on their local thermal sensations of each body part, overall thermal sensation, and overall thermal acceptability on voting scales at regular intervals during the exposure. Results show that the non-uniformity of thermal sensation is a key factor affecting thermal acceptability except for overall thermal sensation. A new assessment model for local cooling was proposed. The model shows that face cooling can improve thermal acceptability more than chest or back cooling, and the upper boundary of the acceptable range of room temperature can be shifted from 26°C to 30.5°C when face cooling is provided.