On the analysis of heat haze effects with spacetime DIC

Long image series (i.e., movies) can be analyzed via digital image correlation (DIC) techniques. A new spacetime implementation is introduced to extend instantaneous DIC with minimal implementation complexity. With this procedure, a denoised reference image is built considering a series of more than 200 images. Such spacetime approach is very interesting when high temperature experiments are performed since it provides a very effective temporal regularization. The analysis of heat haze effects is carried out on a thermomechanical test in which the sample made of ceramic matrix composite is subjected to temperatures greater than 1200 °C in the heat affected zone of the laser beam. It is shown that the addition of a small fan reduces the spurious displacement fluctuations.