| Enhanced tubes can increases the heat transfer performances. and are widely used in power, chemical, petroleum and sea desalt factories. More papers are on the heat transfer performances of enhanced tubes, but few ones are on the fouling characteristics of the tubes. In this paper, experimental studies are carried out on three performances(flow, heat transfer and fouling) of the four enhanced tubes(arc line tube, convergent-divergent tubeâ… , convergent-divergent tubeâ…¡and corrugated tube).Firstly, experimental studies are carried out on the flow performances of the four enhanced tubes at cold position; meanwhile, the heat transfer performances of these tubes are tested at thermal state. The related performance curves and the dimensionless correlation are got. The Experimental result shows that the framework of the enhanced tubes is the primary reason for the changes of heat transfer performance and flow resistance; different enhanced tubes have different exergy efficiency. Moreover, the comparative fouling experiments were carried out between the above four types of tubes and their respective corresponding plain tubes. The experimental working fluid was man-made 800mg/L hardness water or MgO particles, and the experiments were done under the conditions of the same liquid velocity, temperature at the water tank and inlet temperature of the working fluid inside the tubes. The relations between fouling resistances of all these tubes and time were gained from the results of the comparative fouling experiment. The experimental results prove the view that fouling is related to the frameworks of the enhanced tubes and working conditions; the four enhanced tubes are all better than their respective corresponding plain tubes in the anti-fouling performances. Finally, the comparison and analysis are given between the four enhanced tubes and their respective corresponding plain tubes. All these results offer an important reference to the designing and selecting types of enhanced tubes.
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