Heat transfer in a particle curtain falling through a horizontally-flowing gas stream

A study of heat transfer between horizontally-flowing air and a free-falling particle curtain was reported. A steady and uniformly distributed stream of cold particles was fed through a rectangular slit and allowed to fall to form a curtain across the entire width of a horizontal duct of cross-section of 0.15 × 0.60 m. Warm air, at velocities in the range of 0.9 m/s to 1.2 m/s and with a uniform velocity profile, flowed horizontally through the duct. A range of curtain thickness (4 cm to 10 cm) and mass flow rate (0.031 kg/s to 0.040 kg/s) were used to investigate the heat transfer characteristic of the free-falling particle curtain in a uniform cross-flowing gas. Particle temperatures within the curtain and air temperatures outside the curtain were measured as a function of vertical position in the duct. A simple model based on single particle behaviour was developed. The predicted solid temperatures agreed well with the experimental results. However, the predictions for the gas temperatures were less satisfactory.

Graphical abstractA study of heat transfer between horizontally-flowing air and a free-falling particle curtain was reported. A uniform stream of cold particles was fed through a rectangular slit and allowed to fall to form a curtain. A simple model based on single particle behaviour was developed. The predicted solid and gas temperatures were compared with the experimental results.Figure optionsDownload full-size imageDownload as PowerPoint slide