Heat transfer in water spouted beds



Heat transfer from a column wall to water spouted sand beds was studied in a 9 in. diam. steel column. The heat transfer rate to water flowing through a spouted bed was lower than when the column was empty. The presence of a bed suppressed convection currents, causing a large temperature gradient from the wall to the centre of the bed, and consequently a lowered heat transfer rate. At the same water flow rate, the spouted bed gave a lower rate than a fixed bed, because a large fraction of the water bypassed the wall region and flowed up the spout.