Category: Transient Plane Source
Abstract: This study aimed to determine how reliable the Transient Plane Source (TPS) method is when testing semi-transparent materials that have varying extinction coefficients at different temperatures. A numerical experiment has been designed that copies the experimental process and tests the accuracy of the thermal conductivity values that the TPS method generates for semi-transparent materials. After using the TPS Method and comparing the results with the numerical experiment, the study concluded that if the extinction coefficient is less than 2000 m-1 when temperatures are above 600 K, the TPS method will overestimate thermal conductivity of semi-transparent materials. Alternatively, if the extinction coefficient is 500 m-1, TPS method will measure the thermal conductivity as 19.6% higher than what the numerical experiment measures at 1000 K. TPS method will be reliable when the semi-transparent material has an optical thickness greater than 50, and the temperature is maintained under 1000 K.
Reference: Applied Thermal Engineering, 114 (2017) 337-345