Development of a non-invasive optical technique to study liquid evaporation in gas-solid fluidized beds

It was found that for proper processing of the data recorded with the high-speed infrared camera, combination with digital image analysis on images acquired from the visual camera is essential. The application of infrared thermography to gas fluidized beds suffers from the effects of interparticle reflections. The paper addresses the calibration procedure in detail and it is shown how to correct for this. The temperature-dependent effect of the setup window in the calibration is evaluated. To demonstrate the potential of the technique, it has been applied to dry fluidization and fluidization with liquid injection.