Experimental study of thermo-hydraulic and fouling performance of enhanced heat exchangers

The present study investigated the effect of two tube inserts (wire coil and wire mesh) on the heat transfer enhancement, pressure drop and mineral salts fouling mitigation in tube of a heat exchanger. A 3/4-in. tube that is heated by band heaters, is used which simulated a tube of heat exchanger. Working fluid is water with certain quality. The heat transfer rate averagely increased by 22-28% for wire coil (pld=0.125, eld=0.00375) and 163-174% for wire mesh (medium density) over a plain tube value, depending on type of tube insert, density of wire torsion and flow velocity. However, the pressure drop also increased substantially by 46% for wire coil and 500% for wire mesh. Wire coil insert with vibration mitigate mineral salts fouling (scaling) about 34%, and wire mesh have no effect on scaling, however it sometimes increased deposit rate. (C) 2007 Elsevier Ltd. All rights reserved.