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1

Influence of inlet geometry on the efficiency of 1 MW steam turbine

Koprowski Arkadusz, Gotowski Dominik, Rzadkowski Romuald, Szczepanik Ryszard

Journal of KONES

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2019

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Vol. 26, No. 4

119--126

EN

The process of the design of the 1 MW steam turbine includes designing the stator and rotor blades, the steam turbine inlet and exit, the casing and the rotor. A turbine that operates at rotation speeds other than 3000 rpm requires a gearbox and generator with complex electronic software. This article analyses the efficiency of eight turbine variants, including seven inlet geometries and three stages of stator as well as an eight variant with one of the inlets, all three stages and an outlet. This article analyses the efficiency of 8 turbine variants, including four spiral inlet geometries and tree stages in a 1 MW steam turbine. In the article, inlets and 1st stator blades of various geometries were analysed to obtain maximal turbine efficiency. Changing the inlet spiral from one pipe to two pipes increased the turbine efficiency. The geometry of the blades and turbine inlets and outlet was carried out using Design Modeller. The blade mesh was prepared in TurboGrid and inlet in ANSYS Meshing.

2

Ocena wpływu parametrów pary dolotowej do turbiny na efektywność pracy nadkrytycznej siłowni organicznej zasilanej gorącą wodą

Borsukiewicz-Gozdur A., Nowak W.

Prace Naukowe Politechniki Warszawskiej. Konferencje

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2009

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z. 26

81-89

PL

Kotły wodne zazwyczaj służą do zasilania systemów ciepłowniczych. Prowadzono także analizy o możliwości zasilania energią niskotemperaturową elektrowni. W tym ostatnim przypadku na ogół stosuje się siłownie organiczne z obiegiem podkrytycznym ORC. Alternatywą dla takiego rozwiązania siłowni może być elektrownia z siłownią nadkrytyczną z odpowiednio dobraną substancją roboczą w obiegu. W ramach referatu przedstawiono schemat wraz z opisem zasady działania takiej instalacji oraz algorytm obliczeń siłowni nadkrytycznej. Przeprowadzono analizę wpływu parametrów pary świeżej czynnika na efektywność pracy elektrowni przy założeniu, że jest ona zasilana wodą o temperaturze 110°C podgrzewaną w kotle wodnym o mocy nominalnej 600kW opalanym biomasą. Podjęto też próbę porównania siłowni nadkrytycznej z adekwatna siłownią podkrytyczną (ORC) przy założeniu porównywalnych warunków doprowadzania i odprowadzania ciepła do/z układu. Otrzymane wyniki pozwalają jednoznacznie stwierdzić, że zastosowanie siłowni nadkrytycznej w elektrowni niskotemperaturowej pozwala na uzyskanie znacznie wyższych wartości zarówno sprawności jak i mocy.

EN

A water boiler usually serves for supplying heating networks. Carried out were also analyses on the possibility of supply of such systems with low-temperature energy from the power plant. In the latter case usually the organic fluid driven power plants with a subcritical ORC are used. Alternative to the solution of such power plant can be a plant with supercritical parameters of vapour with adequately selected working fluid in the cycle. In the scope of the paper presented is a schematic of such installation together with the principles of operations as well as the algorithm for calculations of a power plant with supercritical parameters of vapour. Conducted has been analysis on the influence of working fluid live vapour parameters on the effectiveness of operation of the power plant at the assumption that the plant is supplied with water with temperature of 110°C heated by the biomass fired water boiler with nominal capacity of 600kW. An attempt has also been made to compare the plant with supercritical parameters with a corresponding subcritical ORC at the assumption of comparable conditions of heat supply and removal from the system. Obtained results enable to anonymously conclude, that implementation of a plant with supercritical parameters in a low-temperature cycle power plant permit to obtain significantly higher values of both the efficiency and power.

3

Applicability of flow simulation models to the case of radial inflow onto a rotating core

Biernacki R.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2001

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Vol. 5, No 2

141-154

EN

The paper presents the results of fluid flow simulations carried out by means of the FIDAP7.6 program (a fluid dynamics FEM package) for the case of radial inflow onto a rotating shaft. The particular geometric configuration has been chosen to resemble a generalized inlet chamber of twin low-pressure steam turbines, but with the axial outlet section extended to allow better observation of flow instabilities in that region. The calculations were carried out for the same channel geometry for both compressible and incompressible flow, using the same or slightly varying boundary conditions. Extensive variation in non-physical parameters of the model was explored, such as applying different meshes over the region, as well as utilizing different turbulence and upwinding models. The intent of this research was to evaluate the relative applicability of the various available flow models to the simulation of axisymmetric flows with steep velocity gradients, and to discover the limitations of these models. The calculations have in fact established significant differences in the behavior of the simulated flow for the different meshes and models. Some results were characterized by extensive areas of recirculating flow whereas others, for the same boundary conditions, showed no recirculation. Correct near-wall meshing as well as the choice of the upwinding scheme were established as the critical factors in this regard. There was also noticeable variation in outlet velocity profiles. An extensive zone of separation within the investigated channel as well as a standing annular vortex near the point of stagnation are flow features of some interest. These patterns of flow change in response to the changing non-physical parameters; the separation zone in particular is absent or slow to develop under some setups. The influence of inflow parameters, the initial velocity distribution and turbulent intensity in particular, on flow behavior in contact with the rotating shaft have also been an area of investigation, as these are often defined with considerable uncertainty in practical applications. It was observed that some latitude in assuming these parameters did not significantly alter the relevant flow parameters at outlet (the velocity and pressure distributions), although it did induce variation in other aspects of the flow (such as the extent of the standing vortex).