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We have developed an instrument for the measurement of microscale infrared (IR) spectroscopic thermal images in a dynamic mode. The high speed image processing based on the two-image technique enables a simultaneous spectroscopic and thermal imaging that detects a dynamic change of IR absorption spectrum by a transmission mode, and the emission of IR radiation from the sample surface. With this dynamic mode scan at 200 Hz, the spectra at any temperatures are free from the base line variation that comes from the temperature dependent surface emission signal, which can be subtracted from the total signal. In addition, the precise calibration between temperature – emissivity in phase transitions has become possible. The phase transitions, from liquid to hexagonal – monoclinic crystal systems, of normal tetracosane (n-C24H50), is presented as an example of the dynamic mode spectroscopic thermal imaging in microscale of normal alkane.

A mathematical method to process data provided by a flying spot technique is studied here, by considering the temperature response field around a unique spot. The progress of optical control, laser and IR Camera allow to measure 2D temperature fields localised on a small area compared to the whole recorded image. The study is focused on the logarithmic expression of the in-plane temperature field in order to analyse and to measure different parameters such as the in plane thermal diffusivity and the localization of the spot. As a perspective, this method can also be used to detect cracks parallel or perpendicular to the surface.

We have been developing the instruments for microscale IR thermography with original optics’ designs and a signal superimposed system, which has been applied to (1) pseudo acceleration of temporal resolution of periodic thermal events, (2) pixel by pixel emissivity-temperature conversion, (3) micro-scale flying spot method. A novel portable instrument design for microscale IR thermography improves the differential temperature and temporal resolution of images that can be obtained even with uncooled detectors.

Arial, 9pt, bold) The mechanisms of CO2 capture by solid adsorbents has been investigated. The understanding of physicochemical mechanisms controlling CO2-adsorbent interactions is primordial for the choice of materials and for the design of industrial capture processes. A key parameter used in these investigations is the heat released during the adsorption of the gas on the adsorbent. Thanks to infrared thermography and an analytical balance, we obtained the estimation of the CO2 adsorption heats on several types of porous materials. This work describes the device and the IR image processing employed to the estimation of the heats of adsorption.

The flash method, known as the most used experimental technique to measure the thermal diffusivity of solids, has been adapted to cylindrical highly diffusive and heterogeneous multilayered samples. In order to overcome the heterogeneities issue and give a more accurate estimation of the sample thermal properties, the front face and rear face thermal responses have been simultaneously recorded over a large characteristic frequency range using an infrared camera. A homogeneous monolithic SiC cylinder has been tested to validate this experimental method which has finally been applied to 2D bi-layered SiCf/SiC cylinders used for nuclear fuel cladding.

In this paper the simultaneous measurement of IR spectroscopic imaging and temperature fields are proposed. First the experimental set-up based on a multispectral monochromator in the IR domain and the methodology will be presented. In this study, the absorbance characterization of the camera detector is shown. Then, by coupling such spectral source with a classical IR camera, images of both the temperature in proper emission and spectroscopy in transmission are presented. The preliminary results show that there is no obstacle to measure simultaneously the temperature and concentration fields as function of time. Then, with this tools it becomes possible to envisaged both thermal analysis (thermophysical properties estimation) and chemical analysis (kinetic) of chemical or phase change processes.