Wyniki wyszukiwania - BazTech

1

Steam turbine stage modernisation in front of the extraction point

Szymaniak M.

Polish Maritime Research

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2018

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nr 2

116--122

EN

The paper presents modernisation of the steam turbine stage situated in front of the turbine extraction point, based on a 225 MW turbine LP stage as an example. The modernised design is intended to better control the steam flow in this area. In the presented design a special ring is used to drive the steam leakage flow directly to the heat exchanger. The performed experiments and numerical analyses confirmed measurable exploitation and efficiency advantages of the introduced modernisation. So far, it has been successfully applied in a number of turbines working in inland power plants, but its use can be easily extended, without need for further modification and without advantage loss, to marine turbines, especially those used as main propulsion in sea-going vessels.

2

Metoda wykrywania nieszczelności w przesyłowych sieciach gazowych (cz. 1)

Osiadacz A. J., Kotyński Ł.

Gaz, Woda i Technika Sanitarna

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2015

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Nr 12

426--431

PL

W artykule omówiono algorytm wykrywania nieszczelności w sieciach gazowych. Algorytm wykorzystuje symulator dynamiczny oparty o paraboliczny model opisujący nieustalony przepływ gazu w rurociągu. Scharakteryzowano zasady wykrywania nieszczelności opracowanym algorytmem oraz zdefiniowano kryteria ustalania wartości wycieku.

EN

The article describes the algorithm for leakage detection in gas networks. The algorithm uses dynamic simulator based on parabolic model which describing the unsteady gas flow within the pipeline. In this article, developed algorithm is characterized and as well as the criteria for determining the value of the leakage is formulated.

3

New Approach to Calculations of Turbine Stages and Regeneration Extraction Points

Szymaniak M.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2008

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Vol. 12, No 3-4

209-215

EN

The article presents 200MW LP turbine stage calculations taking into account leakage flows over rotor blades in the regeneration extraction point area. A methodology is described which allows the user to shorten the time-consuming CFD calculations solving the Navier-Stokes equation system in the examined area. A two-stage procedure was applied in which two types of calculations were coupled together. The first type is a one-to-one passage calculation of a steam flow through the turbine stages in the vicinity of the extraction point. This type of calculations preserves the circumferential periodicity condition. The second type is a circumferentially non-symmetrical calculation of the flow through an inter-stage diffuser with an extraction chamber. The calculations were preformed using 3D CFD codes, FlowER and FLUENT, in the two above mentioned areas, respectively. The solution was found using an iterative procedure for these areas coupled by boundary conditions, until convergence of calculations was reached.

4

Diagnozowanie wycieków z rurociagu modelowego przy zastosowaniu metody gradientowej i metody śledzenia czół fal rozprężeniowych ciśnienia

Ostapkowicz P.

Zeszyty Naukowe Politechniki Białostockiej. Budowa i Eksploatacja Maszyn

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2004

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Z. 12

123-138

PL

Praca dotyczy diagnozowania wycieków z rurociągów. Celem pracy jest poznanie możliwości stosowanych obecnie metod diagnozowania wycieków, tj. metody gradientowej i metody opartej na śledzeniu czół fal rozprężeniowych na przykładzie ich użycia na obiekcie modelowym rurociągu. Prezentowane są ogólne charakterystyki obu metod oraz uzyskane przy ich zastosowaniu wyniki badań diagnostycznych z symulowanymi wyciekami. Badania były prowadzone na specjalnym stanowisku badawczym, z rurociągiem o długości 380 metra.

EN

This work concerns diagnosing of the leakages from pipelines. Knowledge of the possibilities of presently using methods, gradient method and method based on the investigation of propagation of expanded waves' fronts for example their using on pipeline model station is the purpose of this work. The general characteristics of both methods and results diagnostic researches with simulated leakages, conducted on special model station with a 380-meter long pipeline, and by using of both methods has been presented.

5

Fault detection using neuro-fuzzy networks

Kowal M., Korbicz J., Mendes M.J., Calado J.M.

Systems Science

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2002

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Vol. 28, nr 1

45-57

EN

Generally, there methodologies for developing and testing fault detection (FD) algorithms can be distinguished: software benches, hardware benches and industrial data. The current approach uses a hardware bench that consists of process under supervision (two interconnected stations), supervision unit, fault diagnosis unit and fault simulation unit. All elements of the bench are connected to a PROFIBUS network that acts as the communication system exchanging information between automation system and distributed field devices. A realistic and flexible environment for developing and testing FD systems has been constructed using elements commonly used in industry. During the current studies actuator faults, sensor faults and leakages have been considered as incipient and abrupt faults. The proposed FD algorithm is based on neuro-fuzzy models that are responsible for residual generation.

6

Influence of seal leakages on heat transfer performance of rotary air preheaters used in steam generators

Skiepko T., Shah R. K.

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

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1998

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Vol. 53, nr 9

784-791

EN

Deterioration in. Celem przedstawianych rozważań jest ocena ważności the thermal performance of a rotary air preheater is due to leakages from the cold gas to the hot gas and vice versa inherent in the operation. In this paper, first the leakages are classified and then sealing system applied to prevent the leakages is presented. The system includes radial, axial and peripheral seals. The objective of the paper is to estimate significance of each individual seal in the system for thermal performance of rotary regenerators used to preheat combustion air for steam generators. The analysis approach is based on concepts of modelling the preheater as the internal and actual regenerators, as well as all leakages and main flows through a gas flow network. It is found the leakages deteriorate the preheater performance the most through the axial and radial seals, in that order.

PL

W pracy przedstawiono klasyfikację przecieków w regeneracyjnych obrotowych podgrzewaczach powietrza kotłów oraz opisano system uszczelnień podgrzewaczy stosowany w celu zapobiegania tym przeciekom. W systemie tym stosowane są uszczelnienia promieniowe, osiowe i obwodowe poszczególnych uszczelnień w systemie dla wydajności i efektywności podgrzewacza. Podejście zastosowane w analizie jest oparte na ujęciu podgrzewacza jako wewnętrznego i rzeczywistego regeneratorów przy czym przecieki i główne przepływy przedstawia się poprzez sieć przepływów gazów w podgrzewaczu. W rezultacie pokazano, że przecieki przez uszczelnienia, w kolejności, osiowe i promieniowe pogarszają parametry wydajnościowe i efektywność podgrzewacza w największym stopniu.