Modeling of heat transfer from a horizontal tube immersed in a shallow gas fluidized bed

الملخص EN

In this study, modeling of heat transfer from a horizontal tube immersed in a shallow gas fluidized bed was investigated.

The Surface Particle Emulsion heat transfer model SPE and the single particle model were used in the present work as theoretical models to calculate the average heat transfer coefficient at the tube surface.

On the basis of sectorizing the surface of the tube into the three sections (top, side and bottom), The SPE model was used for the top section of the tube and the single particle model was used for the side and bottom of the tube.

The experimental work involved measuring particle residence time at the heat transfer surface by using a 30frame/sec digital camera, and the bubble frequency was used as a measuring tool for predicting the particle residence time at the transfer surface.

The results obtained show that the average heat transfer coefficient increases with the decrease in particle diameter and the increase in the height of the tube above the distributor plate, while tube size has a small influence on average heat transfer coefficient.

The calculated results obtained from the models agreed reasonably well with experimental data.