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Steam condensation analysis in a power plant condenser

Drożyński Z.

Archives of Thermodynamics

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2018

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Vol. 39, no 4

3--32

EN

Proposed is the analysis of steam condensation in the presence of inert gases in a power plant condenser. The presence of inert, noncondensable gases in a condenser is highly undesirable due to its negative effect on the efficiency of the entire cycle. In general, thermodynamics has not provided an explicit criterion for assessing the irreversible heat transfer process. The method presented here enables to evaluate precisely processes occurring in power plant condensers. This real process is of particular interest as it involves a number of thermal layers through which heat transfer is observed. The analysis was performed using a simple, known in the literature and well verified Berman’s model of steam condensation in the presence of non-condensable gases. Adapted to the geometry of the condenser, the model enables, for instance, to recognise places where non-condensable gases are concentrated. By describing with sufficient precision thermodynamic processes taking place in the vicinity of the heat transfer area segment, it is possible to determine the distributions of thermodynamic parameters on the boundaries between successive layers. The obtained results allow for the recognition of processes which contribute in varying degrees to irreversible energy degradation during steam condensation in various parts of the examined device.

2

Entropy increase as a measure of energy degradation in heat transfer

Drożyński Z.

Archives of Thermodynamics

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2013

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Vol. 34, no. 3

147--161

EN

Heat transfer is an irreversible process. This article defines the entropy increment as a measure of energy degradation in heat transfer realized in typical surface heat exchangers. As an example of the proposed entropy increase method, presented below are the calculations for heat exchangers working in a typical Clausius-Rankine cycle. The entropy increase in such exchangers inevitably leads to increased fuel consumption and, as a further consequence, to increased carbon dioxide emission.

3

Phenomenological model of steam condensation containing non-condensable gases on a single, non-inundated horizontal tube

Drożyński Z.

Archives of Thermodynamics

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2006

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Vol. 27, no. 4

67-78

EN

Presented is a two-dimensional model of steam condensation on a non-inundated horizontal tube. The model takes into account heat transfer through a thermal boundary layer consisting of the film of condensate flowing down the heat transfer surface, and the gas part of the layer being the steam-air mixture. Results are presented of calculations of the condensation process as a function of tube length. The analysis was performed for different variants of free and forced convection. The obtained results of calculations were compared with the cases of real condenser tubes in operation in the installation of 200 MW power units.

4

Poprawa procesów wymiany ciepła w skraplaczach poprzez ograniczenie ich zapowietrzenia wynikające z tego efekty energetyczne oraz finansowe

Drożyński Z.

Prace Naukowe Instytutu Techniki Cieplnej i Mechaniki Płynów Politechniki Wrocławskiej. Konferencje

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2000

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Vol. 56, nr 10

253-261

PL

Poniżej omówione zostały rezultaty badań przeprowadzonych na najczęściej spotykanym w polskich elektrociepłowniach bloku ciepłowniczym BC50. Wyniki tych dociekań jako typowe dla bloków energetycznych pracujących w Polsce są z powodzeniem przenoszone na inne obiekty. Przedstawiono reakcję turbogeneratora na zwiększającą się obecność powietrza w skraplaczach.. Omówiono diagnostykę stanu szczelności układów próżniowych. Wyliczono objawy zapowietrzenia wymienników sieciowych bloku ciepłowniczego BC50 i jego skutki termodynamiczne. Opisano zabiegi, których skutkiem jest poprawa procesów wymiany ciepła w skraplaczach. Te rutynowe działania to: modernizacja smoczków, lokalizacja i likwidacja nieszczelności układów próżniowych.

EN

The effect of neutral gases (mainly air) content on the condensation process of steam has been shown. The diagnostics of leakproof quality of vacuum systems has been discussed. Consequences of air presence in heat exchangers of BC50 unit have been named and thermodynamical effects are discussed. The methods to improve the process of heat exchange in condensers are presented.