Unsteady data reduction techniques for QIRT: considerations of temporal and spatial resolution
Ferry F. J. Schrijer · Proceedings of the 2012 International Conference on Quantitative InfraRed Thermography · 2012
The effect of limited temporal resolution and lateral conduction on transient heat flux measurements by means of IR thermography is investigated.In combination three methods are compared that are based on 1D and 2D heat conduction models where the latter are capable of correcting for lateral conduction.It is found that for a constant heat flux without measurement noise 5 to 6 measurement points are sufficient to make a reliable estimate (<1%) of the heat flux.Furthermore it is shown that heat flux features having typical spatial wavelengths that are smaller than 3.5 times the penetration depth are modulated when evaluated by 1D methods that do not take into account lateral conduction.Finally an experimental data set is used to further investigate the above-mentioned effects, however not all theoretical observations could be confirmed indicating the need for further investigation by including a non-constant heat flux and measurement noise.