STUDY ON THERMAL CONDUCTIVITY OF TEAS

A new refined line-source technique is presented for rapid determination of thermal conductivity of teas. The technique is based on the temperature response of a point in an infinite solid near a line-source of heat, and adapted to finite samples for obtaining thermal conductivity. This transient test is very short in duration (under 5min) as comqared with several hours for steady-state devices. Conductivity results are presented for six kinds of Chinese teas. The broken shaped (granular shape) leaves have higher values of thermal conductivity than the eyebrow shaped. The fermented tea leaves have higher values of thermal conductivity than unfermented. The predictive models have been established for describe the relation between the moisture content and thermal conductivity of teas.