DEM Validation of HEAT Transfer in Gas-SOLID Fluidized BED through an New-Integreted DIA/PIV/IR Measuring Technique

ABSTRACT

A new combined IR (infrared)/PIV (particle image velocimetry)/DIA (digital image analysis) measuring technique for studying heat transfer in gas-solid fluidized bed is presented. The infrared images are coupled with visual images that are recorded simultaneously using an external trigger system. This gives instantaneous thermal and hydrodynamic data of a pseudo 2D fluidized bed that can be used to validate simulations of heat transfer in such a bed.

The well-established technique of DIA/ PIV [1,2] can be applied on visual images to get hydrodynamic information and its combination with IR images gives the thermal dynamics. The combined technique was used to get insightful information into issues like the mean temperature of particles as function of time, spatial temperature distributions as function of: particle sizes, bed aspect ratio and background gas velocity. These experimental results were used to validate CFD-DEM models on heat transfer in gas-solid fluidized beds. A state of the art CFD-DEM model code was developed with heat transfer which included gas-particle, particle-particle, particle-wall and gas wall heat transfer. Particulate data from DEM were processed to get the exact same data that was obtained from experimental processing and compared.

keywords:

multiphase flow, particle image velocimetry, digital image analysis, infrared thermography,

fluidized beds, heat transfer, CFD-DEM

[1] de Jong, J., Odu, S., van Buijtenen, M., Deen, N., van Sint Annaland, M., Kuipers, J., 2012. Development and validation of a novel digital image analysis method for fluidized bed particle image velocimetry. Powder Technology 230, 193 – 202.

[2] van Buijtenen, M.S., Burner, M., Deen, N.G., Heinrich, S., Antonyuk, S., Kuipers, J., 2011. An experimental study of the effect of collision properties on spout fluidized bed dynamics. Powder Technology 206, 139 – 148.