HEAT PULSE MEASUREMENT OF THERMAL-PROPERTIES - AN IMPROVED FITTING TECHNIQUE

Transient heat pulse techniques allow specific heat C and thermal cond UCtiVity kappa to be determined from a single measurement. In the main these parameters have previously been derived using linearizations of simplified solutions to the diffusion equation in restricted time reg imes. We present a numerical fitting technique which allows a fit to b e made to the full solution of the diffusion equation across all times of the measurement. This technique also accounts for and allows measu rement of the boundary resistance at the clamped end of the sample, an effect which can cause significant distortion of the measured tempera ture profile. This distortion can lead to significant errors in values of C and kappa derived using other methods.