| Structural parameters of the sintered iron-based porous surface tubes were measured and analyzed in this paper. The mechanical properties of the porous surface tubes were also measured. Results showed that structural parameters of the porous surface tubes produced in the present research are comparable to those made by foreign manufacturers. Mechanical properties met the requirements of national standards, and thus the tubes are qualified for industrial appliations.Porous surface tubes exhibited excellent performance in enhancing boiling heat transfer, with the deionized water, ethanol and xylene as the working fluids. Heat transfer coeffients for porous tubes at constant heat fluxes are 2.89-3.25 times,1.88-2.18 times and 1.87-2.05 times that of the smooth tube, using water, ethanol and xylene respectively.Effects of relative coating thickness and particle size on nucleate boiling performance were investigated. Experimental results revealed that the enhancement in boiling heat transfer with porous tubes can be attributed to the combined influence of particle diameter and coating thickness.An empirical correlation of heat flux q to superheat AT was established in accordance with the experimental data, taking into consideration the structural parameters of porous surfaces and thermophysical properties of the testing fluids. This correlation agrees well with the experimental data with an error within±30%, suggesting its good value in practical applications.
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