Train Pulses with a Random Spatial Distribution to Measure In-Plane Thermal Diffusivity

Abstract

A thermal diffusivity measurement approach is proposed in which the sample is thermally excited by a periodic train of pulsed, spatially random laser light. The temperature field on the surface is observed by IR camera and the diffusion is recorded by a sequence of IR images. The analysis of the diffusion in time and space is followed by suitable models. Fitting of the spatiotemporal evolution of the surface temperature allows to determine the thermal diffusivity of clay brick with an accuracy of 5%.

Keywords

• infrared thermography
• thermal diffusivity
• random pattern
• pulse train