N2 - A mathematical model of the steam superheater exchanger with distributed parameters has been developed. Scale deposits were assumed to be present on the internal tube surfaces. It was assumed that the inner tube surfaces are covered by a thin layer of scale deposits. The finite volume method was used to solve partial differential equations describing flue gas, tube wall and steam temperature. The developed modeling technique can especially be used for modeling tube heat exchangers when detail information on the tube wall temperature distribution is needed. The numerical model of the superheater developed in the paper can be used for modeling of the superheaters with complex flow arrangement accounting scales on the internal tube surfaces. Using the model proposed the detailed steam, wall and flue gas temperature distribution over the entire superheater can be determined. The steam pressure distribution along its path flow and the total heat transfer rate can also be obtained. The calculations showed that the presence of scale on the internal surfaces of the tubes cause the steam temperature decrease and the heat flow rate transferred from the flue gas to the steam. Scale deposits on the inner surfaces of the tubes cause the tube wall temperature growth and can lead to premature wear of tubes due to overheating.
L1 - http://journals.pan.pl/Content/94466/PDF/05_paper.pdf
L2 - http://journals.pan.pl/Content/94466
PY - 2013
IS - No 4 December
EP - 91
DO - 10.2478/aoter-2013-0030
KW - Steam superheater
KW - Scale deposit
KW - Heat exchanger numerical model
A1 - Trojan, Marcin
A1 - Taler, Jan
PB - The Committee of Thermodynamics and Combustion of the Polish Academy of Sciences and The Institute of Fluid-Flow Machinery Polish Academy of Sciences
DA - 2013
T1 - Effect of scale deposits on the internal surfaces of the tubes on the superheater operation
SP - 73
UR - http://journals.pan.pl/dlibra/publication/edition/94466
T2 - Archives of Thermodynamics