MODELLING OF A DELUGEABLE FLAT BARE TUBE BUNDLE FOR AN AIR-COOLED STEAM CONDENSER
DOI:
https://doi.org/10.53555/eijse.v4i2.161Keywords:
Flat, Bare, Delugeable, Dephlegmator, Heat and mass transfer, wet, dry, OnedimensionalAbstract
In this paper, a one dimensional model was developed for the analytical evaluation of the thermal performance of adelugeable flat tube bundle to be incorporated in the second stage of an induced draft hybrid (dry/wet) dephlegmator
(HDWD) of a direct air-cooled steam condenser (ACSC). A one-dimensional model is analysed by using three methods
of analysis which are: Poppe, Merkel, and heat and mass transfer analogy. The model’s accuracy was validated through
a comparison of solutions obtained from the above-mentioned methods of analysis. Satisfactory correlations between theresults were reached. However, heat transfer rate attained by Poppe method is higher by 2.89% and 9.87% than thatobtained by Merkel, and heat and mass analogy methods, respectively. The difference in air-side pressure drop obtainedby all the methods found to be insignificant. Furthermore, the best configuration of the flat tube bundle for the secondstage of induced draft HDWD was identified through the comparison of its performance to the round tube bundle. Theperformance of the round tube bundle is found to be around 2 and 1.5 times of that of flat tube bundle, when both bundles operate in wet and dry operating modes respectively.
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