Steam generators, turbines, and condensers. Volume six

International Nuclear Information System (INIS)

Anon.

1986-01-01

Volume six covers steam generators (How steam is generated, steam generation in a PWR, vertical U-tube steam generators, once-through steam generators, how much steam do steam generators make?), turbines (basic turbine principles, impulse turbines, reaction turbines, turbine stages, turbine arrangements, turbine steam flow, steam admission to turbines, turbine seals and supports, turbine oil system, generators), and condensers (need for condensers, basic condenser principles, condenser arrangements, heat transfer in condensers, air removal from condensers, circulating water system, heat loss to the circulating water system, factors affecting condenser performance, condenser auxiliaries)

User's instructions for ORCENT II: a digital computer program for the analysis of steam turbine cycles supplied by light-water-cooled reactors

International Nuclear Information System (INIS)

Fuller, L.C.

1979-02-01

The ORCENT-II digital computer program will perform calculations at valves-wide-open design conditions, maximum guaranteed rating conditions, and an approximation of part-load conditions for steam turbine cycles supplied with throttle steam characteristic of contemporary light-water reactors. Turbine performance calculations are based on a method published by the General Electric Company. Output includes all information normally shown on a turbine-cycle heat balance diagram. The program is written in FORTRAN IV for the IBM System 360 digital computers at the Oak Ridge National Laboratory

Steam turbines for the future

International Nuclear Information System (INIS)

Trassl, W.

1988-01-01

Approximately 75% of the electrical energy produced in the world is generated in power plants with steam turbines (fossil and nuclear). Although gas turbines are increasingly applied in combined cycle power plants, not much will change in this matter in the future. As far as the steam parameters and the maximum unit output are concerned, a certain consolidation was noted during the past decades. The standard of development and mathematical penetration of the various steam turbine components is very high today and is applied in the entire field: For saturated steam turbines in nuclear power plants and for steam turbines without reheat, with reheat and with double reheat in fossil-fired power plants and for steam turbines with and without reheat in combined cycle power plants. (orig.) [de

Studies and solutions of steam turbines for nuclear heating power stations

International Nuclear Information System (INIS)

Drahy, J.

1979-01-01

The possibilities of combined generation of heat and electric power and special features of the corresponding equipment for WWER type reactors are considered. Condensing steam turbines with bled steam points and the constructional solution of bled points are presented for heating the network water to 110 0 C, 120 0 C, and 160 0 C, respectively. The dimensions of the low pressure final stage of the turbine are given. Problems concerning condensing and bleeding turbines and combination types of back-pressure and condensing turbines as well as solutions to the design of 250 MW and 500 MW turbines are discussed

Composite electric generator equipped with steam generator for heating reactor coolant

International Nuclear Information System (INIS)

Watabe, Masaharu; Soman, Yoshindo; Kawanishi, Kohei; Ota, Masato.

1997-01-01

The present invention concerns a composite electric generator having coolants, as a heating source, of a PWR type reactor or a thermonuclear reactor. An electric generator driving gas turbine is disposed, and a superheater using a high temperature exhaust gas of the gas turbine as a heating source is disposed, and main steams are superheated by the superheater to elevate the temperature at the inlet of the turbine. This can increase the electric generation capacity as well as increase the electric generation efficiency. In addition, since the humidity in the vicinity of the exit of the steam turbine is reduced, occurrence of loss and erosion can be suppressed. When cooling water of the thermonuclear reactor is used, the electric power generated by the electric generator driven by the gas turbine can be used upon start of the thermonuclear reactor, and it is not necessary to dispose a large scaled special power source in the vicinity, which is efficient. (N.H.)

Steam turbines for nuclear power plants

International Nuclear Information System (INIS)

Kosyak, Yu.F.

1978-01-01

Considered are the peculiarities of the design and operation of steam turbines, condensers and supplementary equipment of steam turbines for nuclear power plants; described are the processes of steam flow in humid-steam turbines, calculation and selection principles of main parameters of heat lines. Designs of the turbines installed at the Charkov turbine plant are described in detail as well as of those developed by leading foreign turbobuilding firms

Dynamic computer simulation of the Fort St. Vrain steam turbines

International Nuclear Information System (INIS)

Conklin, J.C.

1983-01-01

A computer simulation is described for the dynamic response of the Fort St. Vrain nuclear reactor regenerative intermediate- and low-pressure steam turbines. The fundamental computer-modeling assumptions for the turbines and feedwater heaters are developed. A turbine heat balance specifying steam and feedwater conditions at a given generator load and the volumes of the feedwater heaters are all that are necessary as descriptive input parameters. Actual plant data for a generator load reduction from 100 to 50% power (which occurred as part of a plant transient on November 9, 1981) are compared with computer-generated predictions, with reasonably good agreement

User's instructions for ORCENT II: a digital computer program for the analysis of steam turbine cycles supplied by light-water-cooled reactors

Energy Technology Data Exchange (ETDEWEB)

Fuller, L.C.

1979-02-01

The ORCENT-II digital computer program will perform calculations at valves-wide-open design conditions, maximum guaranteed rating conditions, and an approximation of part-load conditions for steam turbine cycles supplied with throttle steam characteristic of contemporary light-water reactors. Turbine performance calculations are based on a method published by the General Electric Company. Output includes all information normally shown on a turbine-cycle heat balance diagram. The program is written in FORTRAN IV for the IBM System 360 digital computers at the Oak Ridge National Laboratory.

Improved algorithm based on equivalent enthalpy drop method of pressurized water reactor nuclear steam turbine

International Nuclear Information System (INIS)

Wang Hu; Qi Guangcai; Li Shaohua; Li Changjian

2011-01-01

Because it is difficulty to accurately determine the extraction steam turbine enthalpy and the exhaust enthalpy, the calculated result from the conventional equivalent enthalpy drop method of PWR nuclear steam turbine is not accurate. This paper presents the improved algorithm on the equivalent enthalpy drop method of PWR nuclear steam turbine to solve this problem and takes the secondary circuit thermal system calculation of 1000 MW PWR as an example. The results show that, comparing with the design value, the error of actual thermal efficiency of the steam turbine cycle obtained by the improved algorithm is within the allowable range. Since the improved method is based on the isentropic expansion process, the extraction steam turbine enthalpy and the exhaust enthalpy can be determined accurately, which is more reasonable and accurate compared to the traditional equivalent enthalpy drop method. (authors)

Operating experience feedback report: Reliability of safety-related steam turbine-driven standby pumps. Commercial power reactors, Volume 10

International Nuclear Information System (INIS)

Boardman, J.R.

1994-10-01

This report documents a detailed analysis of failure initiators, causes and design features for steam turbine assemblies (turbines with their related components, such as governors and valves) which are used as drivers for standby pumps in the auxiliary feedwater systems of US commercial pressurized water reactor plants, and in the high pressure coolant injection and reactor core isolation cooling systems of US commercial boiling water reactor plants. These standby pumps provide a redundant source of water to remove reactor core heat as specified in individual plant safety analysis reports. The period of review for this report was from January 1974 through December 1990 for licensee event reports (LERS) and January 1985 through December 1990 for Nuclear Plant Reliability Data System (NPRDS) failure data. This study confirmed the continuing validity of conclusions of earlier studies by the US Nuclear Regulatory Commission and by the US nuclear industry that the most significant factors in failures of turbine-driven standby pumps have been the failures of the turbine-drivers and their controls. Inadequate maintenance and the use of inappropriate vendor technical information were identified as significant factors which caused recurring failures

Large steam turbines for nuclear power stations. Output growth prospects

International Nuclear Information System (INIS)

Riollet, G.; Widmer, M.; Tessier, J.

1975-01-01

The rapid growth of the output of nuclear reactors, even if temporary settlement occurs, leads the manufacturer to evaluate, at a given time, technological limitations encountered. The problems dealing with the main components of turbines: steam path, rotors and stators steam valves, controle devices, shafts and bearings, are reviewed [fr

Control device for steam turbine

International Nuclear Information System (INIS)

Hoshi, Hiroyuki.

1993-01-01

A power load imbalance detection circuit detects a power load imbalance when a load variation coefficient is large and output-load deviation is great. Then, it self-holds and causes a timer to start counting up and releases the self-holding after the elapse of a certain period of time. Upon load separation caused by system accidents, the power load imbalance detection circuit operates along with the increase of turbine rpm, to operate the control valve abrupt closing circuit and a bypassing value abrupt opening circuit. Then, self-holding of the power load imbalance detection circuit is released and, subsequently, a steam control value and a bypass valve are controlled by a control valve flow rate demand signal and a bypass flow rate demand signal determined by an entire main steam flow rate signal and a speed/load control signal. Accordingly, the turbine rpm is settled to about a rated rpm. This enables to avoid reactor shutdown upon occurrence of load interruption. (I.N.)

Reactor trip on turbine trip inhibit control system for nuclear power generating system

International Nuclear Information System (INIS)

Torres, J.M.; Musick, C.R.

1976-01-01

A reactor trip on turbine trip inhibit control system for a nuclear power generating system which utilizes steam bypass valves is described. The control system inhibits a normally automatic reactor trip on turbine trip when the bypass valves have the capability of bypassing enough steam to prevent reactor trip limits from being reached and/or to prevent opening of the secondary safety pressure valves. The control system generates a bypass valve capability signal which is continuously compared with the reactor power. If the capability is greater than the reactor power, then an inhibit signal is generated which prevents a turbine trip signal from tripping the nuclear reactor. 10 claims, 4 figures

Cogeneration steam turbines from Siemens: New solutions

Science.gov (United States)

Kasilov, V. F.; Kholodkov, S. V.

2017-03-01

The Enhanced Platform system intended for the design and manufacture of Siemens AG turbines is presented. It combines organizational and production measures allowing the production of various types of steam-turbine units with a power of up to 250 MWel from standard components. The Enhanced Platform designs feature higher efficiency, improved reliability, better flexibility, longer overhaul intervals, and lower production costs. The design features of SST-700 and SST-900 steam turbines are outlined. The SST-700 turbine is used in backpressure steam-turbine units (STU) or as a high-pressure cylinder in a two-cylinder condensing turbine with steam reheat. The design of an SST-700 single-cylinder turbine with a casing without horizontal split featuring better flexibility of the turbine unit is presented. An SST-900 turbine can be used as a combined IP and LP cylinder (IPLPC) in steam-turbine or combined-cycle power units with steam reheat. The arrangements of a turbine unit based on a combination of SST-700 and SST-900 turbines or SST-500 and SST-800 turbines are presented. Examples of this combination include, respectively, PGU-410 combinedcycle units (CCU) with a condensing turbine and PGU-420 CCUs with a cogeneration turbine. The main equipment items of a PGU-410 CCU comprise an SGT5-4000F gas-turbine unit (GTU) and STU consisting of SST-700 and SST-900RH steam turbines. The steam-turbine section of a PGU-420 cogeneration power unit has a single-shaft turbine unit with two SST-800 turbines and one SST-500 turbine giving a power output of N el. STU = 150 MW under condensing conditions.

Evolution of design of steam generator for sodium cooled reactors

International Nuclear Information System (INIS)

Chetal, S.C.; Vaidyanathan

1997-01-01

The first sodium cooled reactor was the experimental breeder reactor (EBR-I) in usa which was commissioned in 1951 and was incidentally the first nuclear reactor to generate electrical energy. This was followed by fast breeder reactors in USSR, UK, france, USA, japan, germany and India. The use of sodium as a coolant is due to its low moderation which helps in breeding fissile fuel from fertile materials and also its high heat transfer coefficient at comparatively low velocities. The good heat transfer properties introduce thermal stresses when there are rapid changes in the sodium temperatures. Also sodium has a chemical affinity with air and water. The steam generators for sodium cooled reactors have to allow for these novel conditions and in addition, unlike other components. Choices have to be made whether it is a recirculation type as in most fossil plants or an once through unit, the power rating, shape of the tube (straight, helical, U-tube), materials (Ferritic or austenitic), with free level of sodium or not, sodium on tube side or shell side and so on. With higher pressures and steam temperatures reheating steam after partial expansion in the turbine becomes essential as in conventional turbines. For this purpose the choice of reheating fluid viz sodium or live main steam has to be made. This paper traces the evolution of steam generator designs in the different sodium cooled reactors (chronologically) and the operation experience. 16 figs., 1 tab

Steam turbines for nuclear power stations in Czechoslovakia and their use for district heating

International Nuclear Information System (INIS)

Drahy, J.

1989-01-01

The first generation of nuclear power stations in Czechoslavakia is equipped with 440 MW e pressurized water reactors. Each reactor supplies two 220 MW, 3000 rpm condensing type turbosets operating with saturated steam. After the completion of heating water piping systems, all of the 24 units of 220 MW in Czechoslovak nuclear power stations will be operated as dual purpose units, delivering both electricity and heat. At the present time, second-generation nuclear power stations, with 1000 MW e PWRs, are being built. Each such plant is equipped with one 1000 MW full-speed saturated steam turbine. The turbine is so designed as to permit the extraction of steam corresponding to the following quantities of heat: 893 MJ/s with three-stage water heating (150/60 0 C); and 570 MJ/s with two-stage water heating (120/60 0 C). The steam is taken from uncontrolled steam extraction points. (author)

Recent technology for BWR nuclear steam turbine unit

International Nuclear Information System (INIS)

Moriya, Shin-ichi; Masuda, Toyohiko; Kashiwabara, Katsuto; Oshima, Yoshikuni

1990-01-01

As to the ABWR plants which is the third improvement standard boiling water reactor type plants, already the construction of a plant of 1356 MWe class for 50 Hz is planned. Hitachi Ltd. has accumulated the technology for the home manufacture of a whole ABWR plant including a turbine. As the results, the application of a butterfly type combination intermediate valve to No.5 plant in Kashiwazaki Kariwa Nuclear Power Station, Tokyo Electric Power Co., Inc., which began the commercial operation recently and later plants, the application of a moisture separating heater to No.4 plant in Hamaoka Nuclear Power Station, Chubu Electric Power Co., Inc., which is manufactured at present and later plants and so on were carried out. As to the steam turbine facilities for nuclear power generation manufactured by Hitachi Ltd., three turbines of 1100 MWe class for 50 Hz and one turbine for 60 Hz are in operation. As the new technologies for the steam turbines, the development of 52 in long last stage blades, the new design techniques for the rotor system, the moisture separating heater, the butterfly type combination intermediate valve, cross-around pipes and condensate and feedwater system are reported. (K.I.)

How to compute the power of a steam turbine with condensation, knowing the steam quality of saturated steam in the turbine discharge

Energy Technology Data Exchange (ETDEWEB)

Hernandez Albarran, Manuel Jaime; Krever, Marcos Paulo Souza [Braskem, Sao Paulo, SP (Brazil)

2009-07-01

To compute the power and the thermodynamic performance in a steam turbine with condensation, it is necessary to know the quality of the steam in the turbine discharge and, information of process variables that permit to identifying with high precision the enthalpy of saturated steam. This paper proposes to install an operational device that will expand the steam from high pressure point on the shell turbine to atmosphere, both points with measures of pressure and temperature. Arranging these values on the Mollier chart, it can be know the steam quality value and with this data one can compute the enthalpy value of saturated steam. With the support of this small instrument and using the ASME correlations to determine the equilibrium temperature and knowing the discharge pressure in the inlet of surface condenser, the absolute enthalpy of the steam discharge can be computed with high precision and used to determine the power and thermodynamic efficiency of the turbine. (author)

The main features of control and operation of steam turbines at nuclear power plants

International Nuclear Information System (INIS)

Czinkoczky, B.

1981-01-01

The output and speed control of steam turbines at nuclear power plants as well as the combination of both controls are reviewed and evaluated. At the same time the tasks of unit control at nuclear power plants, the control of steady main steam pressure and medium pressure of primary circuit, further the connection of reactor and turbine controls and the self-controlling properties of pressurized water reactor are dealt with. Hydraulic and electro-hydraulic speed control, the connection of cach-up dampers and speed control and the application of electro-hydraulic signal converters are discussed. The accomplishment of protection is also described. (author)

Steam generators in indirect-cycle water-cooled reactors

International Nuclear Information System (INIS)

Fajeau, M.

1976-01-01

In the indirect cycle water-cooled nuclear reactors, the steam generators are placed between the primary circuit and the turbine. They act both as an energy transmitter and as a leaktigh barrier against fission or corrosion products. Their study is thus very important from a performance and reliability point of view. Two main types are presented here: the U-tube and the once-through steam generators [fr

Power plant and system for accelerating a cross compound turbine in such plant, especially one having an HTGR steam supply

International Nuclear Information System (INIS)

Jaegtnes, K.O.; Braytenbah, A.S.

1977-01-01

An electric power plant having a cross compound steam turbine and a steam source that includes a high temperature gas-cooled nuclear reactor is described. The steam turbine includes high and intermediate-pressure portions which drive a first generating means, and a low-pressure portion which drives a second generating means. The steam source supplies superheat steam to the high-pressure turbine portion, and an associated bypass permits the superheat steam to flow from the source to the exhaust of the high-pressure portion. The intermediate and low-pressure portions use reheat steam; an associated bypass permits reheat steam to flow from the source to the low-pressure exhaust. An auxiliary turbine driven by steam exhausted from the high-pressure portion and its bypass drives a gas blower to propel the coolant gas through the reactor. While the bypass flow of reheat steam is varied to maintain an elevated pressure of reheat steam upon its discharge from the source, both the first and second generating means and their associated turbines are accelerated initially by admitting steam to the intermediate and low-pressure portions. The electrical speed of the second generating means is equalized with that of the first generating means, whereupon the generating means are connected and acceleration proceeds under control of the flow through the high-pressure portion. 29 claims, 2 figures

Variable electricity and steam from salt, helium and sodium cooled base-load reactors with gas turbines and heat storage - 15115

International Nuclear Information System (INIS)

Forsberg, C.; McDaniel, P.; Zohuri, B.

2015-01-01

Advances in utility natural-gas-fired air-Brayton combed cycle technology is creating the option of coupling salt-, helium-, and sodium-cooled nuclear reactors to Nuclear air-Brayton Combined Cycle (NACC) power systems. NACC may enable a zero-carbon electricity grid and improve nuclear power economics by enabling variable electricity output with base-load nuclear reactor operations. Variable electricity output enables selling more electricity at times of high prices that increases plant revenue. Peak power is achieved using stored heat or auxiliary fuel (natural gas, bio-fuels, hydrogen). A typical NACC cycle includes air compression, heating compressed air using nuclear heat and a heat exchanger, sending air through a turbine to produce electricity, reheating compressed air, sending air through a second turbine, and exhausting to a heat recovery steam generator (HRSG). In the HRSG, warm air produces steam that is used to produce added electricity. For peak power production, auxiliary heat (natural gas, stored heat) is added before the air enters the second turbine to raise air temperatures and power output. Like all combined cycle plants, water cooling requirements are dramatically reduced relative to other power cycles because much of the heat rejection is in the form of hot air. (authors)

Operating results of 220 MW SKODA saturated steam turbines

International Nuclear Information System (INIS)

Drahy, J.

1992-01-01

One of the steam turbines produced by the SKODA Works, the 220 MW steam turbine for saturated admission steam of a speed of 3000 r.p.m. is described; it is used in nuclear power plants with 400 MW PWR type reactors. 16 units of 8 turbines each have been in operation in the Jaslovske Bohunice and Dukovany power plants with the total period of operation of all machines exceeding 750,000 hours. The 220 MW steam turbine consists of a two-flow high-pressure section and of two identical two-flow low-pressure sections. The pressure of saturated steam at the inlet of the high-pressure section is 4.32 MPa (the corresponding temperature of the saturation limit being 255 degC) and during the expansion in the high-pressure section it drops to 0.6 MPa; steam moisture reaches 12%. In a separator and two-stage reheater using blend steam, the steam is freed of the moisture and is reheated to a temperature of 217 degC. Some operational problems are discussed, as are the loss of the material of the stator parts of the high-pressure section due to corrosion-erosion wear and corrosion-erosion wear of the guide wheels of the high-pressure section, and measures are presented carried out for the reduction of the corrosion-erosion effects of wet steam. One of the serious problems were the fatigue fractures of the blades of the 4th high-pressure stage, which appeared after 20 000 to 24 000 hours of operation in the dented tee-root. The guide wheels of the 4th stage were substituted by new guide wheels with uniform pitch of the channels and with increased number of guide blades. Also discussed are the dynamic behavior of the low-pressure section of the bridge structure, the operating reliability and the heat off-take for water heating of long-distance heating systems. (Z.S.) 9 figs

Integrating a SOFC Plant with a Steam Turbine Plant

DEFF Research Database (Denmark)

Rokni, Masoud; Scappin, Fabio

2009-01-01

A Solid Oxide Fuel Cell (SOFC) is integrated with a Steam Turbine (ST) cycle. Different hybrid configurations are studied. The fuel for the plants is assumed to be natural gas (NG). Since the NG cannot be sent to the anode side of the SOFC directly, a desulfurization reactor is used to remove...

Gas--steam turbine combined cycle power plants

Energy Technology Data Exchange (ETDEWEB)

Christian, J.E.

1978-10-01

The purpose of this technology evaluation is to provide performance and cost characteristics of the combined gas and steam turbine, cycle system applied to an Integrated Community Energy System (ICES). To date, most of the applications of combined cycles have been for electric power generation only. The basic gas--steam turbine combined cycle consists of: (1) a gas turbine-generator set, (2) a waste-heat recovery boiler in the gas turbine exhaust stream designed to produce steam, and (3) a steam turbine acting as a bottoming cycle. Because modification of the standard steam portion of the combined cycle would be necessary to recover waste heat at a useful temperature (> 212/sup 0/F), some sacrifice in the potential conversion efficiency is necessary at this temperature. The total energy efficiency ((electric power + recovered waste heat) divided by input fuel energy) varies from about 65 to 73% at full load to 34 to 49% at 20% rated electric power output. Two major factors that must be considered when installing a gas--steam turbine combines cycle are: the realiability of the gas turbine portion of the cycle, and the availability of liquid and gas fuels or the feasibility of hooking up with a coal gasification/liquefaction process.

Moisture separators and reheaters for wet steam turbines

International Nuclear Information System (INIS)

Gibbins, J.

1979-01-01

Moisture separator reheater (M.S.R.) units are now a well established feature of the wet steam cycle as associated with the various types of water cooled reactor. This paper describes the development of M.S.Rs. as supplied by GEC for turbine generators of up to 1200 MW ratings covering the design procedures used and the features required to ensure efficient and reliable operation. In addition to details of the M.S.R. design, the desirable features of the steam supply, venting and drain control systems are also discussed. The recent developments, as provided on current projects, are described. (author)

Thermoelastic steam turbine rotor control based on neural network

Science.gov (United States)

Rzadkowski, Romuald; Dominiczak, Krzysztof; Radulski, Wojciech; Szczepanik, R.

2015-12-01

Considered here are Nonlinear Auto-Regressive neural networks with eXogenous inputs (NARX) as a mathematical model of a steam turbine rotor for controlling steam turbine stress on-line. In order to obtain neural networks that locate critical stress and temperature points in the steam turbine during transient states, an FE rotor model was built. This model was used to train the neural networks on the basis of steam turbine transient operating data. The training included nonlinearity related to steam turbine expansion, heat exchange and rotor material properties during transients. Simultaneous neural networks are algorithms which can be implemented on PLC controllers. This allows for the application neural networks to control steam turbine stress in industrial power plants.

Thermodynamic analysis of steam-injected advanced gas turbine cycles

Science.gov (United States)

Pandey, Devendra; Bade, Mukund H.

2017-12-01

This paper deals with thermodynamic analysis of steam-injected gas turbine (STIGT) cycle. To analyse the thermodynamic performance of steam-injected gas turbine (STIGT) cycles, a methodology based on pinch analysis is proposed. This graphical methodology is a systematic approach proposed for a selection of gas turbine with steam injection. The developed graphs are useful for selection of steam-injected gas turbine (STIGT) for optimal operation of it and helps designer to take appropriate decision. The selection of steam-injected gas turbine (STIGT) cycle can be done either at minimum steam ratio (ratio of mass flow rate of steam to air) with maximum efficiency or at maximum steam ratio with maximum net work conditions based on the objective of plants designer. Operating the steam injection based advanced gas turbine plant at minimum steam ratio improves efficiency, resulting in reduction of pollution caused by the emission of flue gases. On the other hand, operating plant at maximum steam ratio can result in maximum work output and hence higher available power.

Nuclear turbine efficiency improvement by wet steam study

International Nuclear Information System (INIS)

Nishikawa, Tsuyoshi; Morson, A.; Markytan, R.

2000-01-01

Most of the turbine used at the nuclear power plant are operated at environment of wet steam, which composes of a big factor of its inner loss in comparison with those of the thermal power plant. If an analytical method predictable on behavior of the wet steam is established, it could be upgraded efficiency of the turbine and also reliability against corrosion formed by moisture. This study, therefore, aims at understanding of physical property of the wet steam flow scarcely known at present, development of an optimum turbine cascade design tool reflected by the property, development of a turbine cascade design reducible of steam loss due to wet steam by using the tool, and development on a method of removing moisture in the turbine to its outer portion. For the tool, a new three dimensional flow numerical analysis is necessary to be developed, to aim at accurately and numerically understanding of the behavior of wet steam. As this study is in advancing now, by using a turbine cascade optimized on the wet steam flow and a developed moisture removing apparatus, about 0.6 % of upgrading in turbine efficiency can be predicted in comparison with that of the advanced aero-cascade of the GE Corporation. (G.K.)

Technology of turbine plant operating with wet steam

International Nuclear Information System (INIS)

1989-01-01

The technology of turbine plant operating with wet steam is a subject of continuing interest and importance, notably in view of the widespread use of wet steam cycles in nuclear power plants and the recent developments of advanced low pressure blading for both conventional and wet steam turbines. The nature of water formation in expanding steam has an important influence on the efficiency of turbine blading and on the integrity and safe operating life of blading and associated turbine and plant components. The subjects covered in this book include research, flow analysis and measurement, development and design of turbines and ancillary plant, selection of materials of construction, manufacturing methods and operating experience. (author)

1000 MW steam turbine for Temelin nuclear power station

International Nuclear Information System (INIS)

Drahy, J.

1992-01-01

Before the end 1991 the delivery was completed of the main parts (3 low-pressure sections and 1 high-pressure section, all of double-flow design) of the first full-speed (3000 r.p.m.) 1000 MW steam turbine for saturated admission steam for the Temelin nuclear power plant. Description of the turbine design and of new technologies and tools used in the manufacture are given. Basic technical parameters of the steam turbine are as follows: maximum output of steam generators 6060 th -1 ; maximum steam flow into turbine 5494.7 th -1 ; output of turbo-set 1024 MW; steam conditions before the turbine inlet: pressure 5.8 MPa, temperature 273.3 degC, steam wetness 0.5%; nominal temperature of cooling water 21 degC; temperature of feed water 220.8 degC; maximum consumption of heat from turbine for heating at 3-stage heating of heating water 60/150 degC. (Z.S.) 7 figs., 2 refs

Wet steam wetness measurement in a 10 MW steam turbine

Directory of Open Access Journals (Sweden)

Kolovratník Michal

2014-03-01

Full Text Available The aim of this paper is to introduce a new design of the extinction probes developed for wet steam wetness measurement in steam turbines. This new generation of small sized extinction probes was developed at CTU in Prague. A data processing technique is presented together with yielded examples of the wetness distribution along the last blade of a 10MW steam turbine. The experimental measurement was done in cooperation with Doosan Škoda Power s.r.o.

Steam turbine of WWER-1000 unit

International Nuclear Information System (INIS)

Drahy, J.

1986-01-01

The manufacture was started by Skoda of a saturated steam, 1,000 MW, 3,000 rpm turbine designed for the Temelin nuclear power plant. The turbine provides steam for heating water for district heating, this either with an output of 893 MW for a three-stage water heating at 150/60 degC, or of 570 MW for a two-stage water heating at 120/60 degC. The turbine features one high-pressure and three identical low-pressure stages. The pressure gradient between the high-pressure and the low-pressure parts was optimized with respect to the thermal efficiency of the cycle and to the thermodynamic efficiency of the low-pressure part. A value of 0.79 MPa was selected corresponding to the maximum through-flow of steam entering the turbine. This makes 5,495 t/h, the admission steam parameters are 273.3 degC and 5.8 MPa. The feed water temperature is 220.9 degC. 300 cold starts, 1,000 starts after shutdowns for 55 to 88 hours and 600 starts after shutdown for 8 hours are envisaged for the entire turbine service life. (Z.M.). 5 figs., 1 tab., 6 refs

Genetic optimization of steam multi-turbines system

International Nuclear Information System (INIS)

Olszewski, Pawel

2014-01-01

Optimization analysis of partially loaded cogeneration, multiple-stages steam turbines system was numerically investigated by using own-developed code (C++). The system can be controlled by following variables: fresh steam temperature, pressure, and flow rates through all stages in steam turbines. Five various strategies, four thermodynamics and one economical, which quantify system operation, were defined and discussed as an optimization functions. Mathematical model of steam turbines calculates steam properties according to the formulation proposed by the International Association for the Properties of Water and Steam. Genetic algorithm GENOCOP was implemented as a solving engine for non–linear problem with handling constrains. Using formulated methodology, example solution for partially loaded system, composed of five steam turbines (30 input variables) with different characteristics, was obtained for five strategies. The genetic algorithm found multiple solutions (various input parameters sets) giving similar overall results. In real application it allows for appropriate scheduling of machine operation that would affect equable time load of every system compounds. Also based on these results three strategies where chosen as the most complex: the first thermodynamic law energy and exergy efficiency maximization and total equivalent energy minimization. These strategies can be successfully used in optimization of real cogeneration applications. - Highlights: • Genetic optimization model for a set of five various steam turbines was presented. • Four various thermodynamic optimization strategies were proposed and discussed. • Operational parameters (steam pressure, temperature, flow) influence was examined. • Genetic algorithm generated optimal solutions giving the best estimators values. • It has been found that similar energy effect can be obtained for various inputs

A system for regulating the pressure of resuperheated steam in high temperature gas-cooled reactor power stations

International Nuclear Information System (INIS)

Braytenbah, A.S.; Jaegines, K.O.

1975-01-01

The invention relates to a system for regulating steam-pressure in the re-superheating portion of a steam-boiler receiving heat from a gas-cooled high temperature nuclear reactor, provided with gas distributing pumps driven by steam-turbines. The system comprises means for generating a pressure signal of desired magnitude for the re-superheating portion, and means for providing a real pressure in the re-superheating portion, means (including a by-passing device) for generating steam-flow rate signal of desired magnitude, a turbine by-pass device comprising a by-pass tapping means for regulating the steam-flow-rate in said turbine according to the desired steam-flow rate signal and means for controlling said by-pass tapping means according to said desired steam-flow-rate signal [fr

Specific features of steam turbine design at LMZ

International Nuclear Information System (INIS)

Pichugin, I.I.; Tsvetkov, A.M.; Simkin, M.S.

1993-01-01

General structural layouts of the condensation steam turbines produced by the Leningrad metalworks (LM) are considered. Currently LM produced 50 types and modifications of steam turbines with the capacity from 30 up to 1200 MW. Problems of turbine efficiency and ways of the flow section improvement are discussed

Large nuclear steam turbine plants

International Nuclear Information System (INIS)

Urushidani, Haruo; Moriya, Shin-ichi; Tsuji, Kunio; Fujita, Isao; Ebata, Sakae; Nagai, Yoji.

1986-01-01

The technical development of the large capacity steam turbines for ABWR plants was partially completed, and that in progress is expected to be completed soon. In this report, the outline of those new technologies is described. As the technologies for increasing the capacity and heightening the efficiency, 52 in long blades and moisture separating heaters are explained. Besides, in the large bore butterfly valves developed for making the layout compact, the effect of thermal efficiency rise due to the reduction of pressure loss can be expected. As the new technology on the system side, the simplification of the turbine system and the effect of heightening the thermal efficiency by high pressure and low pressure drain pumping-up method based on the recent improvement of feed water quality are discussed. As for nuclear steam turbines, the actual records of performance of 1100 MW class, the largest output at present, have been obtained, and as a next large capacity machine, the development of a steam turbine of 1300 MWe class for an ABWR plant is in progress. It can be expected that by the introduction of those new technologies, the plants having high economical efficiency are realized. (Kako, I.)

Steam Turbine Control Valve Stiction Effect on Power System Stability

International Nuclear Information System (INIS)

Halimi, B.

2010-01-01

One of the most important problems in power system dynamic stability is low frequency oscillations. This kind of oscillation has significant effects on the stability and security of the power system. In some previous papers, a fact was introduced that a steam pressure continuous fluctuation in turbine steam inlet pipeline may lead to a kind of low frequency oscillation of power systems. Generally, in a power generation plant, steam turbine system composes of some main components, i.e. a boiler or steam generator, stop valves, control valves and turbines that are connected by piping. In the conventional system, the turbine system is composed with a lot of stop and control valves. The steam is provided by a boiler or steam generator. In an abnormal case, the stop valve shuts of the steal flow to the turbine. The steam flow to the turbine is regulated by controlling the control valves. The control valves are provided to regulate the flow of steam to the turbine for starting, increasing or decreasing the power, and also maintaining speed control with the turbine governor system. Unfortunately, the control valve has inherent static friction (stiction) nonlinearity characteristics. Industrial surveys indicated that about 20-30% of all control loops oscillate due to valve problem caused by this nonlinear characteristic. In this paper, steam turbine control valve stiction effect on power system oscillation is presented. To analyze the stiction characteristic effect, firstly a model of control valve and its stiction characteristic are derived by using Newton's laws. A complete tandem steam prime mover, including a speed governing system, a four-stage steam turbine, and a shaft with up to for masses is adopted to analyze the performance of the steam turbine. The governor system consists of some important parts, i.e. a proportional controller, speed relay, control valve with its stiction characteristic, and stem lift position of control valve controller. The steam turbine has

Steam turbines of large output especially for nuclear power stations. Part 1

International Nuclear Information System (INIS)

Drahny, J.; Stasny, M.

1986-01-01

At the international conference, 53 papers were presented in 3 sessions dealing with the design of large output steam turbines, with problems of flow in steam turbines, and with the reliability and service life of steam turbines. Part 1 of the conference proceedings contains two introductory papers, one reviewing the 100 years history of steam turbines (not included in INIS), the other giving an overview of the development of steam turbines in the eighties; and the 13 papers heard in the session on steam turbine design, all inputted in INIS. (A.K.)

Natural gas turbine topping for the iris reactor

International Nuclear Information System (INIS)

Oriani, L.; Lombardi, C.; Paramonov, D.

2001-01-01

Nuclear power plant designs are typically characterized by high capital and low fuel costs, while the opposite is true for fossil power generation including the natural gas-fired gas turbine combined cycle currently favored by many utilities worldwide. This paper examines potential advantages of combining nuclear and fossil (natural gas) generation options in a single plant. Technical and economic feasibility and attractiveness of a gas turbine - nuclear reactor combined cycle where gas turbine exhaust is used to superheat saturated steam produced by a low power light water reactor are examined. It is shown that in a certain range of fuel and capital costs of nuclear and fossil options, the proposed cycle offers an immediate economic advantage over stand-alone plants resulting from higher efficiency of the nuclear plant. Additionally, the gas turbine topping will result in higher fuel flexibility without the economic penalty typically associated with nuclear power. (author)

Natural gas turbine topping for the iris reactor

Energy Technology Data Exchange (ETDEWEB)

Oriani, L.; Lombardi, C. [Politecnico di Milano, Milan (Italy); Paramonov, D. [Westinghouse Electric Corp., LLC, Pittsburgh, PA (United States)

2001-07-01

Nuclear power plant designs are typically characterized by high capital and low fuel costs, while the opposite is true for fossil power generation including the natural gas-fired gas turbine combined cycle currently favored by many utilities worldwide. This paper examines potential advantages of combining nuclear and fossil (natural gas) generation options in a single plant. Technical and economic feasibility and attractiveness of a gas turbine - nuclear reactor combined cycle where gas turbine exhaust is used to superheat saturated steam produced by a low power light water reactor are examined. It is shown that in a certain range of fuel and capital costs of nuclear and fossil options, the proposed cycle offers an immediate economic advantage over stand-alone plants resulting from higher efficiency of the nuclear plant. Additionally, the gas turbine topping will result in higher fuel flexibility without the economic penalty typically associated with nuclear power. (author)

Flow characteristics in nuclear steam turbine blade passage

International Nuclear Information System (INIS)

Ahn, H.J.; Yoon, W.H.; Kwon, S.B.

1995-01-01

The rapid expansion of condensable gas such as moist air or steam gives rise to nonequilibrium condensation. As a result of irreversibility of condensation process in the nuclear steam turbine blade passage, the entropy of the flow increases, and the efficiency of the turbine decreases. In the present study, in order to investigate the flow characteristics of moist air in two-dimensional turbine blade passage which is made from the configuration of the last stage tip section of the actual nuclear steam turbine moving blade, the static pressures along both pressure and suction sides of blade are measured by static pressure taps and the distribution of Mach number on both sides of the blade are obtained by using the measured static pressure. Also, the flow field is visualized by a Schlieren system. From the experimental results, the effects of the stagnation temperature and specific humidity on the flow properties in the two dimensional steam turbine blade passage are clearly identified

Check of condition of steam generators, volume compensators and turbine condensers in nuclear power plants

International Nuclear Information System (INIS)

Matal, O.; Klinga, J.; Holy, F.; Sobotka, J.

1989-01-01

A negative pressure leak detector is described designed for leak testing of tubes in steam generators and steam turbine condensers. The principle, operation and use are described of inflatable bags and an inflatable platform. The bags are designed for insulating and sealing spaces in nuclear reactor components while the inflatable platform is used in pressurizer inspections and repairs. Their properties, and other facilities for detecting leaks in steam generator tubes are briefly described. (M.D.). 3 figs

Performance Modelling of Steam Turbine Performance using Fuzzy ...

African Journals Online (AJOL)

Performance Modelling of Steam Turbine Performance using Fuzzy Logic ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES. Journal of Applied Sciences and Environmental Management ... A Fuzzy Inference System for predicting the performance of steam turbine

Development of a nuclear steam generator system for gas-cooled reactors for application in oil sands extraction

International Nuclear Information System (INIS)

Smith, J.; Hart, R.; Lazic, L.

2009-01-01

Canada has vast energy reserves in the Oil Sands regions of Alberta and Saskatchewan. Present extraction technologies, such as strip mining, where oil deposits are close to the surface, and Steam Assisted Gravity Drainage (SAGD) technologies for deeper deposits consume significant amounts of energy to produce the bitumen and upgraded synthetic crude oil. Studies have been performed to assess the feasibility of using nuclear reactors as primary energy sources to produce, in particular the steam required for the SAGD deeper deposit extraction process. Presently available reactors fall short of meeting the requirements, in two areas: the steam produced in a 'standard' reactor is too low in pressure and temperature for the SAGD process. Requirements can be for steam as high as 12MPa pressure with superheat; and, 'standard' reactors are too large in total output. Ideally, reactors of output in the range of 400 to 500 MWth, in modules are better suited to Oil Sands applications. The above two requirements can be met using gas-cooled reactors. Generally, newer generation gas-cooled reactors have been designed for power generation, using Brayton Cycle gas turbines run directly from the heated reactor coolant (helium). Where secondary steam is required, heat recovery steam generators have been used. In this paper, a steam generating system is described which uses the high temperature helium from the reactor directly for steam generation purposes, with sufficient quantities of steam produced to allow for SAGD steam injection, power generation using a steam turbine-generator, and with potential secondary energy supply for other purposes such as hydrogen production for upgrading, and environmental remediation processes. It is assumed that the reactors will be in one central location, run by a utility type organization, providing process steam and electricity to surrounding Oil Sands projects, so steam produced is at very high pressure (12 MPa), with superheat, in order to

Steam relief valve control system for a nuclear reactor

International Nuclear Information System (INIS)

Torres, J.M.

1976-01-01

Described is a turbine follow system and method for Pressurized Water Reactors utilizing load bypass and/or atmospheric dump valves to provide a substitute load upon load rejection by bypassing excess steam to a condenser and/or to the atmosphere. The system generates a variable pressure setpoint as a function of load and applies an error signal to modulate the load bypass valves. The same signal which operates the bypass valves actuates a control rod automatic withdrawal prevent to insure against reactor overpower

1000 MW steam turbine for nuclear power station

International Nuclear Information System (INIS)

Drahy, J.

1987-01-01

Skoda Works started the manufacture of the 1000 MW steam turbine for the Temelin nuclear power plant. The turbine will use saturated steam at 3,000 r.p.m. It will allow steam supply to heat water for district heating, this of an output of 893 MW for a three-stage water heating at a temperature of 150/60 degC or of 570 MW for a two-stage heating at a temperature of 120/60 degC. The turbine features one high-pressure and three identical low-pressure stages. The pressure gradient between the high-pressure and the low-pressure parts was optimized as concerns the thermal efficiency of the cycle and the thermodynamic efficiency of the low-pressure part. A value of 0.79 MPa was selected corresponding to the maximum flow rate of the steam entering the turbine. This is 5,495 t/h, the admission steam parameters are 273.3 degC and 5.8 MPa. The feed water temperature is 220.9 degC. It is expected that throughout the life of the turbine, there will be 300 cold starts, 1,000 starts following shutdown for 55 to 88 hours, and 600 starts following shutdown for 8 hours. (Z.M.). 8 figs., 1 ref

Data Reconciliation in the Steam-Turbine Cycle of a Boiling Water Reactor

International Nuclear Information System (INIS)

Sunde, Svein; Berg, Oivind; Dahlberg, Lennart; Fridqvist, Nils-Olof

2003-01-01

A mathematical model for a boiling water reactor steam-turbine cycle was assembled by means of a configurable, steady-state modeling tool TEMPO. The model was connected to live plant data and intermittently fitted to these by minimization of a weighted least-squares object function. The improvement in precision achieved by this reconciliation was assessed from quantities calculated from the model equations linearized around the minimum and from Monte Carlo simulations. It was found that the inclusion of the flow-passing characteristics of the turbines in the model equations significantly improved the precision as compared to simple mass and energy balances, whereas heat transfer calculations in feedwater heaters did not. Under the assumption of linear model equations, the quality of the fit can also be expressed as a goodness-of-fit Q. Typical values for Q were in the order of 0.9. For a validated model Q may be used as a fault detection indicator, and Q dropped to very low values in known cases of disagreement between the model and the plant state. The sensitivity of Q toward measurement faults is discussed in relation to redundancy. The results of the linearized theory and Monte Carlo simulations differed somewhat, and if a more accurate analysis is required, this is better based on the latter. In practical application of the presently employed techniques, however, assessment of uncertainties in raw data is an important prerequisite

HTGR power plant hot reheat steam pressure control system

International Nuclear Information System (INIS)

Braytenbah, A.S.; Jaegtnes, K.O.

1975-01-01

A control system for a high temperature gas cooled reactor (HTGR) power plant is disclosed wherein such plant includes a plurality of steam generators. Dual turbine-generators are connected to the common steam headers, a high pressure element of each turbine receiving steam from the main steam header, and an intermediate-low pressure element of each turbine receiving steam from the hot reheat header. Associated with each high pressure element is a bypass line connected between the main steam header and a cold reheat header, which is commonly connected to the high pressure element exhausts. A control system governs the flow of steam through the first and second bypass lines to provide for a desired minimum steam flow through the steam generator reheater sections at times when the total steam flow through the turbines is less than such minimum, and to regulate the hot reheat header steam pressure to improve control of the auxiliary steam turbines and thereby improve control of the reactor coolant gas flow, particularly following a turbine trip. (U.S.)

Wet steam turbines for nuclear generating stations -design and operating experience

International Nuclear Information System (INIS)

Usher, J.

1977-01-01

Lecture to the Institution of Nuclear Engineers, 11 Jan. 1977. The object of this lecture was to give an account of some design features of large wet steam turbines and to show by describing some recent operational experience how their design concepts were fulfilled. Headings are as follows: effects of wet steam cycle on turbine layout and operation (H.P. turbine, L.P. turbine); turbine control and operation; water separators; and steam reheaters. (U.K.)

Recent technology for nuclear steam turbine-generator units

International Nuclear Information System (INIS)

Moriya, Shin-ichi; Kuwashima, Hidesumi; Ueno, Takeshi; Ooi, Masao

1988-01-01

As the next nuclear power plants subsequent to the present 1,100 MWe plants, the technical development of ABWRs was completed, and the plan for constructing the actual plants is advanced. As for the steam turbine and generator facilities of 1,350 MWe output applied to these plants, the TC6F-52 type steam turbines using 52 in long blades, moisture separation heaters, butterfly type intermediate valves, feed heater drain pumping-up system and other new technologies for increasing the capacity and improving the thermal efficiency were adopted. In this paper, the outline of the main technologies of those and the state of examination when those are applied to the actual plants are described. As to the technical fields of the steam turbine system for ABWRs, the improvement of the total technologies of the plants was promoted, aiming at the good economical efficiency, reliability and thermal efficiency of the whole facilities, not only the main turbines. The basic specification of the steam turbine facilities for 50 Hz ABWR plants and the main new technologies applied to the turbines are shown. The development of 52 in long last stage blades, the development of the analysis program for the coupled vibration of the large rotor system, the development of moisture separation heaters, the turbine control system, condensate and feed water system, and the generators are described. (Kako, I.)

Future development of large steam turbines

International Nuclear Information System (INIS)

Chevance, A.

1975-01-01

An attempt is made to forecast the future of the large steam turbines till 1985. Three parameters affect the development of large turbines: 1) unit output; and a 2000 to 2500MW output may be scheduled; 2) steam quality: and two steam qualities may be considered: medium pressure saturated or slightly overheated steam (light water, heavy water); light enthalpie drop, high pressure steam, high temperature; high enthalpic drop; and 3) the quality of cooling supply. The largest range to be considered might be: open system cooling for sea-sites; humid tower cooling and dry tower cooling. Bi-fluid cooling cycles should be also mentioned. From the study of these influencing factors, it appears that the constructor, for an output of about 2500MW should have at his disposal the followings: two construction technologies for inlet parts and for high and intermediate pressure parts corresponding to both steam qualities; exhaust sections suitable for the different qualities of cooling supply. The two construction technologies with the two steam qualities already exist and involve no major developments. But, the exhaust section sets the question of rotational speed [fr

Structural integrity analysis of a steam turbine

International Nuclear Information System (INIS)

Villagarcia, Maria P.

1997-01-01

One of the most critical components of a power utility is the rotor of the steam turbine. Catastrophic failures of the last decades have promoted the development of life assessment procedures for rotors. The present study requires the knowledge of operating conditions, component geometry, the properties of materials, history of the component, size, location and nature of the existing flaws. The aim of the present work is the obtention of a structural integrity analysis procedure for a steam turbine rotor, taking into account the above-mentioned parameters. In this procedure, a stress thermal analysis by finite elements is performed initially, in order to obtain the temperature and stress distribution for a subsequent analysis by fracture mechanics. The risk of a fast fracture due to flaws in the central zone of the rotor is analyzed. The procedure is applied to an operating turbine: the main steam turbine of the Atucha I nuclear power utility. (author)

Methods of increasing thermal efficiency of steam and gas turbine plants

Science.gov (United States)

Vasserman, A. A.; Shutenko, M. A.

2017-11-01

Three new methods of increasing efficiency of turbine power plants are described. Increasing average temperature of heat supply in steam turbine plant by mixing steam after overheaters with products of combustion of natural gas in the oxygen. Development of this idea consists in maintaining steam temperature on the major part of expansion in the turbine at level, close to initial temperature. Increasing efficiency of gas turbine plant by way of regenerative heating of the air by gas after its expansion in high pressure turbine and before expansion in the low pressure turbine. Due to this temperature of air, entering combustion chamber, is increased and average temperature of heat supply is consequently increased. At the same time average temperature of heat removal is decreased. Increasing efficiency of combined cycle power plant by avoiding of heat transfer from gas to wet steam and transferring heat from gas to water and superheated steam only. Steam will be generated by multi stage throttling of the water from supercritical pressure and temperature close to critical, to the pressure slightly higher than condensation pressure. Throttling of the water and separation of the wet steam on saturated water and steam does not require complicated technical devices.

A detection of the coarse water droplets in steam turbines

Directory of Open Access Journals (Sweden)

Bartoš Ondřej

2014-03-01

Full Text Available The aim of this paper is to introduce a novel method for the detection of coarse water droplets in a low pressure part of steam turbines. The photogrammetry method has been applied for the measurement of coarse droplets in the low-pressure part of a steam turbine. A new probe based on this measurement technique was developed and tested in the laboratory and in a steam turbine in the Počerady power-plant. The probe was equipped with state-of-the-art instrumentation. The paper contains results from laboratory tests and the first preliminary measurements in a steam turbine. Possible applications of this method have been examined.

Effect of thermal barrier coatings on the performance of steam and water-cooled gas turbine/steam turbine combined cycle system

Science.gov (United States)

Nainiger, J. J.

1978-01-01

An analytical study was made of the performance of air, steam, and water-cooled gas-turbine/steam turbine combined-cycle systems with and without thermal-barrier coatings. For steam cooling, thermal barrier coatings permit an increase in the turbine inlet temperature from 1205 C (2200 F), resulting in an efficiency improvement of 1.9 percentage points. The maximum specific power improvement with thermal barriers is 32.4 percent, when the turbine inlet temperature is increased from 1425 C (2600 F) to 1675 C (3050 F) and the airfoil temperature is kept the same. For water cooling, the maximum efficiency improvement is 2.2 percentage points at a turbine inlet temperature of 1683 C (3062 F) and the maximum specific power improvement is 36.6 percent by increasing the turbine inlet temperature from 1425 C (2600 F) to 1730 C (3150 F) and keeping the airfoil temperatures the same. These improvements are greater than that obtained with combined cycles using air cooling at a turbine inlet temperature of 1205 C (2200 F). The large temperature differences across the thermal barriers at these high temperatures, however, indicate that thermal stresses may present obstacles to the use of coatings at high turbine inlet temperatures.

A condenser for very high power steam turbines

International Nuclear Information System (INIS)

Gardey, Robert.

1973-01-01

The invention relates to a condenser for very high power steam turbines under the masonry-block supporting the low-pressure stages of the turbine, that condenser comprises two horizontal aligned water-tube bundles passing through the steam-exhaust sleeves of the low-pressure stages, on both sides of a common inlet water box. The invention can be applied in particular to the 1000-2000 MW turbines of light water nuclear power stations [fr

Steam temperature variation behind a turbine steam separator-superheater during NPP start-up

International Nuclear Information System (INIS)

Lejzerovich, A.Sh.; Melamed, A.D.

1979-01-01

To determine necessary parameters of the steam temperature automatic regulator behind the steam separator-rheater supe (SSS) of an NPP turbine the static and dynamic characteristics of the temperature change behind the SSS were studied experimentally. The measurements were carried out at the K-220-44 turbine of the Kolskaja NPP in the case of both varying turbine loads and the flow rate of the heating vapor. Disturbances caused by the opening of the regulating valve at the inlet of the heating vapor are investigated as well. It is found that due to a relatively high inertiality of the SSS a rather simple structure of the start-up steam temperature regulators behind the SSS in composition with automatated driving systems of the turbine start-up without regard for the change of the dynamic characteristics can be used

The market for steam turbine generators around the world

International Nuclear Information System (INIS)

Mandement, O.; Anglaret, P.; Ledermann, P.

2012-01-01

As a discrete market (in the mathematical meaning of the word) with irregular sales from one year to the next, the market for steam turbine generators in nuclear plants requires working out a strategy adapted to each project. The diversity of the reactors proposed (technology, thermal power, the thermodynamic characteristics of the steam supplied), the variety of the cold sources to be used (ranging from the Baltic Sea to the Indian Ocean) and the different frequencies of electricity grids (50 or 60 Hz) necessitate developing platforms of solutions. Furthermore, the requirement that local businesses have a share in contracts often entails partnerships. After pointing out the diversity of this market, the effort is made to point out its principal characteristics. (authors)

Technical and economic studies of small reactors for supply of electricity and steam

International Nuclear Information System (INIS)

Spiewak, I.; Klepper, O.H.; Fuller, L.C.

1977-01-01

Several years ago conventional opinion held that nuclear power plants must be very large to be competitive with fossil fuels. This situation has changed markedly in most countries within recent years, as oil and gas supplies have become more scarce and costly. Studies have been carried out of several nuclear steam supply systems in the small and intermediate size range. Detail studies are reported of the Consolidated Nuclear Steam Generator (CNSG), a 313 MW(t) pressurized water reactor being developed by Babcock and Wilcox, as applied to industrial energy needs. Both conventional and barge-mounted nuclear steam supply systems are considered. Conceptual studies have been started of pressurized and boiling water reactors in the range of 1000 MW(t), which are envisioned for utility operation for supply of electric power and steam. Design studies of a 500 MW(t) high temperature reactor are also reported. The small reactors are expected to have higher unit costs than the large commercial plants, but to have compensating advantages in higher plant availability, shorter construction schedule and greater siting flexibility. Studies are also reported of power cycle parameters and cost allocations for extraction of steam from steam turbine plants. This steam could be used for industrial energy, district heating or desalination

Technical and economic studies of small reactors for supply of electricity and steam

International Nuclear Information System (INIS)

Spiewak, I.; Klepper, O.H.; Fuller, L.C.

1977-02-01

Several years ago conventional opinion held that nuclear power plants must be very large to be competitive with fossil fuels. This situation has changed markedly in most countries within recent years, as oil and gas supplies have become more scarce and costly. Studies have been carried out for several nuclear steam supply systems in the small and intermediate size range. Detail studies are reported of the Consolidated Nuclear Steam Generator (CNSG), a 365 MW(th) pressurized water reactor being developed by Babcock and Wilcox, as applied to industrial energy needs. Both conventional and barge-mounted nuclear steam supply systems are considered. Conceptual studies have been started of pressurized and boiling water reactors in the range of 1000 MW(th), which are envisioned for utility operation for supply of electric power and steam. Design studies of a 500 MW(th) high temperature reactor are also reported. The small reactors are expected to have higher unit costs than the large commercial plants, but to have compensating advantages in higher plant availability, shorter construction schedule, and greater siting flexibility. Studies are also reported of power cycle parameters and cost allocations for extraction of steam from steam turbine plants. This steam could be used for industrial energy, district heating, or desalination

Technical and economic studies of small reactors for supply of electricity and steam

International Nuclear Information System (INIS)

Spiewak, I.; Klepper, O.H.; Fuller, L.C.

1977-01-01

Several years ago conventional opinion held that nuclear power plants must be very large to be competitive with fossil fuels. This situation has changed markedly in most countries within recent years, as oil and gas supplies have become more scarce and costly. Studies have been carried out of several nuclear steam supply systems in the small and intermediate size range. Detail studies are reported of the Consolidated Nuclear Steam Generator (CNSG), a 313MW(th) pressurized water reactor being developed by Babcock and Wilcox, as applied to industrial energy needs. Both conventional and barge-mounted nuclear steam supply systems are considered. Conceptual studies have been started of pressurized and boiling water reactors in the range of 1000MW(th), which are envisioned for utility operation for supply of electric power and steam. Design studies of a 500MW(th) high temperature reactor are also reported. The small reactors are expected to have higher unit costs than the large commercial plants, but to have compensating advantages in higher plant availability, shorter construction schedule and greater siting flexibility. Studies are also reported of power cycle parameters and cost allocations for extraction of steam from steam turbine plants. This steam could be used for industrial energy, district heating or desalination. (author)

Time program using in automatization of steam turbines start-up

International Nuclear Information System (INIS)

Lejzerovich, A.Sh.; Melamed, A.D.

Examples and arguments for developing time programs of changing basic parameters of automated start-up of TPP and NPP high-power steam turbines are considered. Basic parameters subject to controlled changing at automatization of turbine start-up are rotation frequency, loading and temperature of steam supplied to the turbine. Principle facility schemes of program regulation of steam temperature at the start-up are presented. The facility scheme of loading the NPP wet steam turbine is given. The principles of developing time programs, of changing basic parameters of automated start-up enable realizing transient processes close to theoretically optimum processes at arbitrary prestart-up state of the turbine by means of rather simple autatic facilities. In particular, for automated temperature increase of steam supplied to the turbine of TES power units and AES turbine loading, it is advisable to use programs in the form of linear dependence of velocity of changing the controlled parameter on the given value, the initial level, from which the parameter increase with a regulated velocity is realized, is given in the form of analogue dependence on the turbine prestart-up state. The programs described and the schemes of their realization have been approved at the automatization of 300 MW power unit starts up with the K-300-240 turbine and K-220-44 turbine as well as used when creating control system for turbines of 500 MW and higher for designed TPP and NPP power units

Main trends of upgrading the 1000 MW steam turbine

International Nuclear Information System (INIS)

Drahy, J.

1990-01-01

Parameters are compared for the 1000 MW steam turbine manufactured by the Skoda Works, Czechoslovakia, and turbines in the same power range by other manufacturers, viz. ABB, Siemens/KWU, GEC and LMZ. The Skoda turbine compares well with the other turbines with respect to all design parameters, and moreover, enables the most extensive heat extraction for district heating purposes. The main trends in upgrading this turbine are outlined; in particular, they include an additional increase in the heat extraction, which is made possible by a new design of the low-pressure section or by using a ''satellite'' turbine. The studies performed also indicate that the output of the full-speed saturated steam turbine can be increased to 1300 MW. An experimental turbine representing one flow of the high-pressure part of the 1000 MW turbine is being built on the 1:1 scale. It will serve to verify the methods of calculation of the wet steam flow and to experimentally test the high-pressure part over a wide span of the parameters. (Z.M.). 1 tab., 3 figs., 7 refs

Liquid-phase problems in steam turbine LP stages

International Nuclear Information System (INIS)

Blanc-Feraud, P.

1978-01-01

Wet steam formation owing to incipient condensation in final steam turbine pressure stages results in a loss of efficiency and possible rotor blading erosion. The effects of erosion are now clearly understood and quite easily counteracted, but loss of thermodynamics, mechanical and aerodynamic efficiency is still a problem. Only the final LP stages of conventional power station plant operate with wet steam, whereas nuclear plant turbines use it to produce most of their total output [fr

Technical diagnostics of steam turbines

International Nuclear Information System (INIS)

Vlckova, B.; Drahy, J.

1987-01-01

This paper deals with practical experience in application of technical diagnostics methods to steam turbines, in particular using pedestal and shaft vibration measurements as well as estimation of bearing metal temperature and ultrasound emission signals. An estimation of effectiveness of the diagnostics methods used is given on the basis of experimental investigations made on a 30-MW turbine. (author)

Study of PWR reactor efficiency as a function of turbine steam extractions

International Nuclear Information System (INIS)

Rocha, Janine Gandolpho da; Alvim, Antonio Carlos Marques; Martinez, Aquilino Senra

2002-01-01

The objective of this work is to optimize the extractions of the low-pressure turbine of a PWR nuclear reactor, in order to obtain the best thermodynamic cycle efficiency. We have analyzed typical data of a 1300 MW PWR reactor, operating at 25%, 50%, 75% and 100% capacities, respectively. The first stage of this study consists of generating a mathematical model capable of describing the reactor behavior and efficiency at any power level. The second stage of this study consists of to combine the generated mathematical model in an optimization computer program that optimize the extractions flow of the low-pressure turbine until it finds the optimal system efficiency. This work does not alter the nuclear facility project in any way. (author)

Evaluation of the Gas Turbine Modular Helium Reactor

Energy Technology Data Exchange (ETDEWEB)

1994-02-01

Recent advances in gas-turbine and heat exchanger technology have enhanced the potential for a Modular Helium Reactor (MHR) incorporating a direct gas turbine (Brayton) cycle for power conversion. The resulting Gas Turbine Modular Helium Reactor (GT-MHR) power plant combines the high temperature capabilities of the MHR with the efficiency and reliability of modern gas turbines. While the passive safety features of the steam cycle MHR (SC-MHR) are retained, generation efficiencies are projected to be in the range of 48% and steam power conversion systems, with their attendant complexities, are eliminated. Power costs are projected to be reduced by about 20%, relative to the SC-MHR or coal. This report documents the second, and final, phase of a two-part evaluation that concluded with a unanimous recommendation that the direct cycle (DC) variant of the GT-MHR be established as the commercial objective of the US Gas-Cooled Reactor Program. This recommendation has been endorsed by industrial and utility participants and accepted by the US Department of Energy (DOE). The Phase II effort, documented herein, concluded that the DC GT-MHR offers substantial technical and economic advantages over both the IDC and SC systems. Both the DC and IDC were found to offer safety advantages, relative to the SC, due to elimination of the potential for water ingress during power operations. This is the dominant consequence event for the SC. The IDC was judged to require somewhat less development than the direct cycle, while the SC, which has the greatest technology base, incurs the least development cost and risk. While the technical and licensing requirements for the DC were more demanding, they were judged to be incremental and feasible. Moreover, the DC offers significant performance and cost improvements over the other two concepts. Overall, the latter were found to justify the additional development needs.

Evaluation of the Gas Turbine Modular Helium Reactor

International Nuclear Information System (INIS)

1994-02-01

Recent advances in gas-turbine and heat exchanger technology have enhanced the potential for a Modular Helium Reactor (MHR) incorporating a direct gas turbine (Brayton) cycle for power conversion. The resulting Gas Turbine Modular Helium Reactor (GT-MHR) power plant combines the high temperature capabilities of the MHR with the efficiency and reliability of modern gas turbines. While the passive safety features of the steam cycle MHR (SC-MHR) are retained, generation efficiencies are projected to be in the range of 48% and steam power conversion systems, with their attendant complexities, are eliminated. Power costs are projected to be reduced by about 20%, relative to the SC-MHR or coal. This report documents the second, and final, phase of a two-part evaluation that concluded with a unanimous recommendation that the direct cycle (DC) variant of the GT-MHR be established as the commercial objective of the US Gas-Cooled Reactor Program. This recommendation has been endorsed by industrial and utility participants and accepted by the US Department of Energy (DOE). The Phase II effort, documented herein, concluded that the DC GT-MHR offers substantial technical and economic advantages over both the IDC and SC systems. Both the DC and IDC were found to offer safety advantages, relative to the SC, due to elimination of the potential for water ingress during power operations. This is the dominant consequence event for the SC. The IDC was judged to require somewhat less development than the direct cycle, while the SC, which has the greatest technology base, incurs the least development cost and risk. While the technical and licensing requirements for the DC were more demanding, they were judged to be incremental and feasible. Moreover, the DC offers significant performance and cost improvements over the other two concepts. Overall, the latter were found to justify the additional development needs

Gas-cooled nuclear reactor

International Nuclear Information System (INIS)

1974-01-01

The invention aims at simplying gas-cooled nuclear reactors. For the cooling gas, the reactor is provided with a main circulation system comprising one or several energy conversion main groups such as gas turbines, and an auxiliary circulation system comprising at least one steam-generating boiler heated by the gas after its passage through the reactor core and adapted to feed a steam turbine with motive steam. The invention can be applied to reactors the main groups of which are direct-cycle gas turbines [fr

Steam plant for pressurized water reactors

International Nuclear Information System (INIS)

Anon.

1983-01-01

This book discusses the research and development organisations and users to highlight those aspects of the steam turbine and associated plant which are particularly related to the PWR system. The contents include: Characteristics of the steam system (including feed train, dump system and safety aspects); overall design aspects of high and half speed turbines; design aspects of the steam generator and seismic considerations; moisture separators and reheaters; feed pumps and their drives; water treatment; safety related valves; operational experience; availability and performance

Steam turbines of large output. Vol. 1, 2, 3

International Nuclear Information System (INIS)

1989-01-01

The proceedings contain 52 papers of which 14 have been inputted in INIS. They concern the development of high output turbines for power plants, the designing and testing of moisture separators, aerodynamics and vibrations of revolving parts of turbines, turbines suitable for heat extraction, the calculations and testing of steam flow characteristics, the mathematical model of thermodynamic cycles in wet steam, reliability, corrosion, and the questions of economics. (M.D.)

Methods for calculating the speed-up characteristics of steam-water turbines

International Nuclear Information System (INIS)

Golovach, E.A.

1981-01-01

The methods of approximate and specified calculations of speed- up characteristics of steam-water turbines are considered. The specified non-linear method takes into account change of thermal efficiency, heat drop and losses in the turbine as well as vacuum break-up the condenser. Speed-up characteristics of the K-1000-60-1500 turbine are presented. The calculational results obtained by the non-linear method are compared with the calculations conducted by the approximate linearized method. Differences in the frequency speed up of the turbine rotor rotation calculated by the two methods constitute only 0.5-2.0%. That is why it is necessary to take into account in the specified calculations first of all the most important factors following the rotor speed- up in the following consequence: valve shift of the high pressure cylinder (HPC); steam volume in front of the HPC; shift of the valves behind the separator-steam superheater (SSS); steam volumes and moisture boiling in the SSS; steam consumption for regenerating heating of feed water, steam volumes at the intermediate elements of the turbine, losses in the turbine, heat drop and thermal efficiency [ru

Cast Alloys for Advanced Ultra Supercritical Steam Turbines

Energy Technology Data Exchange (ETDEWEB)

G. R. Holcomb, P. Wang, P. D. Jablonski, and J. A. Hawk,

2010-05-01

The proposed steam inlet temperature in the Advanced Ultra Supercritical (A-USC) steam turbine is high enough (760 °C) that traditional turbine casing and valve body materials such as ferritic/martensitic steels will not suffice due to temperature limitations of this class of materials. Cast versions of several traditionally wrought Ni-based superalloys were evaluated for use as casing or valve components for the next generation of industrial steam turbines. The full size castings are substantial: 2-5,000 kg each half and on the order of 100 cm thick. Experimental castings were quite a bit smaller, but section size was retained and cooling rate controlled to produce equivalent microstructures. A multi-step homogenization heat treatment was developed to better deploy the alloy constituents. The most successful of these cast alloys in terms of creep strength (Haynes 263, Haynes 282, and Nimonic 105) were subsequently evaluated by characterizing their microstructure as well as their steam oxidation resistance (at 760 and 800 °C).

Steam drums

International Nuclear Information System (INIS)

Crowder, R.

1978-01-01

Steam drums are described that are suitable for use in steam generating heavy water reactor power stations. They receive a steam/water mixture via riser headers from the reactor core and provide by means of separators and driers steam with typically 0.5% moisture content for driving turbines. The drums are constructed as prestressed concrete pressure vessels in which the failure of one or a few of the prestressing elements does not significantly affect the overall strength of the structure. The concrete also acts as a radiation shield. (U.K.)

Wet-steam erosion of steam turbine disks and shafts

International Nuclear Information System (INIS)

Averkina, N. V.; Zheleznyak, I. V.; Kachuriner, Yu. Ya.; Nosovitskii, I. A.; Orlik, V. G.; Shishkin, V. I.

2011-01-01

A study of wet-steam erosion of the disks and the rotor bosses or housings of turbines in thermal and nuclear power plants shows that the rate of wear does not depend on the diagrammed degree of moisture, but is determined by moisture condensing on the surfaces of the diaphragms and steam inlet components. Renovating the diaphragm seals as an assembly with condensate removal provides a manifold reduction in the erosion.

Materials for advanced ultrasupercritical steam turbines

Energy Technology Data Exchange (ETDEWEB)

Purgert, Robert [Energy Industries Of Ohio Inc., Independence, OH (United States); Shingledecker, John [Energy Industries Of Ohio Inc., Independence, OH (United States); Saha, Deepak [Energy Industries Of Ohio Inc., Independence, OH (United States); Thangirala, Mani [Energy Industries Of Ohio Inc., Independence, OH (United States); Booras, George [Energy Industries Of Ohio Inc., Independence, OH (United States); Powers, John [Energy Industries Of Ohio Inc., Independence, OH (United States); Riley, Colin [Energy Industries Of Ohio Inc., Independence, OH (United States); Hendrix, Howard [Energy Industries Of Ohio Inc., Independence, OH (United States)

2015-12-01

The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have sponsored a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired power plants capable of operating at much higher efficiencies than the current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of advanced ultrasupercritical (A-USC) steam conditions. A limiting factor in this can be the materials of construction for boilers and for steam turbines. The overall project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760°C (1400°F)/35MPa (5000 psi). This final technical report covers the research completed by the General Electric Company (GE) and Electric Power Research Institute (EPRI), with support from Oak Ridge National Laboratory (ORNL) and the National Energy Technology Laboratory (NETL) – Albany Research Center, to develop the A-USC steam turbine materials technology to meet the overall project goals. Specifically, this report summarizes the industrial scale-up and materials property database development for non-welded rotors (disc forgings), buckets (blades), bolting, castings (needed for casing and valve bodies), casting weld repair, and casting to pipe welding. Additionally, the report provides an engineering and economic assessment of an A-USC power plant without and with partial carbon capture and storage. This research project successfully demonstrated the materials technology at a sufficient scale and with corresponding materials property data to enable the design of an A-USC steam turbine. The key accomplishments included the development of a triple-melt and forged Haynes 282 disc for bolted rotor construction, long-term property development for Nimonic 105 for blading and bolting, successful scale-up of Haynes 282 and Nimonic 263 castings using

Repairing methods of steam turbine blades using welding procedures

International Nuclear Information System (INIS)

Mazur, Z.; Cristalinas, V.; Kubiak, J.

1995-01-01

The steam turbine blades are subjected to the natural permanent wear or damage, which may be of mechanical or metallurgical origin. The typical damage occurring during the lifetime of turbine blading may be erosion, corrosion, foreign objects damage, rubbing and cracking caused by high cycle fatigue and creep crack growth. The nozzle and diaphragm vanes (stationary blades) of the steam turbine are elements whose damage is commonly occurring and they require special repair processes. The damage of the blade trailing edge of nozzle and diaphragm vanes, due to the former causes, may be refurbished by welding deposits or stainless steel inserts welded to the blades. Both repair methods of the stationary steam turbine blades are presented. The results of the blades refurbishment are an increase of the turbine availability, reliability and efficiency, and a decrease of the risk that failure will occur. Also, the repair cost versus the spare blades cost represent significant reduction of expenditure. 7 refs

Corrosion cracking of rotor steels of steam turbines

International Nuclear Information System (INIS)

Melekhov, R.K.; Litvintseva, E.N.

1994-01-01

Results of investigation of stress corrosion cracking of steam turbine materials in nuclear, fossil and geothermal power plants have been analysed. The role of factors that cause damage to rotor discs, mono block and welding rotors of steam turbines has been shown. These are yield stress and steel composition, stress intensity coefficient and crack growth rate, composition and temperature of the condensed steam and water, electrochemical conditions. The conclusion has been made about the state of stress corrosion cracking of the rotors materials, and main investigation trends which are necessary to solve this problem have been listed

Aerodynamic instabilities in governing valves of steam turbines

International Nuclear Information System (INIS)

Richard, J.M.; Pluviose, M.

1991-01-01

The capacity of a.c. turbogenerators in a Pressurized Water Reactor (PWR) is regulated by means of governing valves located at the inlet of the high-pressure turbine. The conditions created in these valves (due to the throttling of the steam) involve the generation of a jet structure, possibly supersonic. Aerodynamic instabilities could potentially excite the mechanical structure. These aerodynamic phenomena are studied in this paper by means of a two-dimensional numerical model. Viscous effects are taken into account with heuristic criteria on separation and reattachment. Detailed experimental analysis of the flow behaviour is compared with the numerical prediction of stability limits. (Author)

Turbine main engines

CERN Document Server

Main, John B; Herbert, C W; Bennett, A J S

1965-01-01

Turbine Main Engines deals with the principle of operation of turbine main engines. Topics covered include practical considerations that affect turbine design and efficiency; steam turbine rotors, blades, nozzles, and diaphragms; lubricating oil systems; and gas turbines for use with nuclear reactors. Gas turbines for naval boost propulsion, merchant ship propulsion, and naval main propulsion are also considered. This book is divided into three parts and begins with an overview of the basic mode of operation of the steam turbine engine and how it converts the pressure energy of the ingoing ste

Preliminary conceptual design of the secondary sodium circuit-eliminated JSFR (Japan Sodium Fast Reactor) adopting a supercritical CO2 turbine system (2). Turbine system and plant size

International Nuclear Information System (INIS)

Kisohara, Naoyuki; Sakamoto, Yoshihiko; Kotake, Shoji

2014-09-01

Research and development of the supercritical CO 2 (S-CO 2 ) cycle turbine system is underway in various countries for further improvement of the safety and economy of sodium-cooled fast reactors. The Component Design and Balance-Of-Plant (CD and BOP) of the Generation IV International Nuclear Forum (Gen-IV) has addressed this study, and their analytical and experimental results have been discussed between the relevant countries. JAEA, who is a member of the CD and BOP, has performed a design study of an S-CO 2 gas turbine system applied to the Japan Sodium-cooled Fast Reactor (JSFR). In this study, the S-CO 2 cycle turbine system was directly connected to the primary sodium system of the JSFR to eliminate the secondary sodium circuit, aiming for further economical improvement. This is because there is no risk of sodium-water reaction in the S-CO 2 cycle turbine system of SFRs. This report describes the system configuration, heat/mass balance, and main components of the S-CO 2 turbine system, based on the JSFR specifications. The layout of components and piping in the reactor and turbine buildings were examined and the dimensions of the buildings were estimated. The study has revealed that the reactor and turbine buildings could be reduced by 7% and 40%, respectively, in comparison with those in the existing JSFR design with the secondary sodium circuit employing the steam turbine. The cycle thermal was also calculated as 41.9-42.3%, which is nearly the same as that of the JSFR with the water/steam system. (author)

Study on the behavior of moisture droplets in low pressure steam turbines

International Nuclear Information System (INIS)

Kimura, Y.; Kuramoto, Y.; Yoshida, K.; Etsu, M.

1978-01-01

Low pressure stages of fossil turbines and almost all stages of nuclear and geothermal turbines operate on wet steam. Turbine operating on wet steam have the following two disadvantages: decrease of efficiency and erosion of blades. Decrease of efficiency results from an increase in profile loss caused by water films on the blade surface; loss of steam energy in breaking up the films and accelerating moisture droplets; undercooling and condensation shocks associated with it; velocity difference between water and steam phases and consequent decelerating action of moisture droplets in the rotating blades, etc. Impingement of moisture droplets on the rotating blades also causes quick erosion of the blades. In this paper, the behavior of moisture droplets in wet steam flow is described and the correlation between their behavior and the abovementioned two disadvantages of turbines operating on wet steam is clarified. (author)

Super titanium blades for advanced steam turbines

International Nuclear Information System (INIS)

Coulon, P.A.

1990-01-01

In 1986, the Alsthom Steam Turbines Department launched the manufacture of large titanium alloy blades: airfoil length of 1360 mm and overall length of 1520 mm. These blades are designed for the last-stage low pressure blading of advanced steam turbines operating at full speed (3000 rpm) and rating between 300 and 800 MW. Using titanium alloys for steam turbine exhaust stages as substitutes for chrome steels, due to their high strength/density ratio and their almost complete resistance to corrosion, makes it possible to increase the length of blades significantly and correspondingly that steam passage section (by up to 50%) with a still conservative stresses level in the rotor. Alsthom relies on 8 years of experience in the field of titanium, since as early as 1979 large titanium blades (airfoil length of 1240 mm, overall length of 1430 mm) were erected for experimental purposes on the last stage of a 900 MW unit of the Dampierre-sur-Loire power plant and now totals 45,000 operating hours without problems. The paper summarizes the main properties (chemical, mechanical and structural) recorded on very large blades and is based in particular on numerous fatigue corrosion test results to justify the use of the Ti 6 Al 4 V alloy in a specific context of micrographic structure

Steam feeding redundancy for turbine-drives of feed pumps at WWER-1000 NPP

International Nuclear Information System (INIS)

Nesterov, Yu.V.; Shmukler, B.I.

1987-01-01

The system of steam supply for feed pump driving turbines (T) at the South Ukrainian Unit 1 according to the centralized redundancy principle is described. T is feeded through the collector of water auxiliary sytem (CWAS) to which steam from the third steam extraction line of turbine is supplied under thenormal regime. Under the reduction of turbine load, live steam from the steam generator is supplied to CWAS through the pressure regulator, possesing 10 s speed of responce. In this case the level reduction in the steam generator makes up 170 mm

Research on simulation of supercritical steam turbine system in large thermal power station

Science.gov (United States)

Zhou, Qiongyang

2018-04-01

In order to improve the stability and safety of supercritical steam turbine system operation in large thermal power station, the body of the steam turbine is modeled in this paper. And in accordance with the hierarchical modeling idea, the steam turbine body model, condensing system model, deaeration system model and regenerative system model are combined to build a simulation model of steam turbine system according to the connection relationship of each subsystem of steam turbine. Finally, the correctness of the model is verified by design and operation data of the 600MW supercritical unit. The results show that the maximum simulation error of the model is 2.15%, which meets the requirements of the engineering. This research provides a platform for the research on the variable operating conditions of the turbine system, and lays a foundation for the construction of the whole plant model of the thermal power plant.

Method for extending the unrestricted operating range of condensing steam turbines

International Nuclear Information System (INIS)

Csaba, G.; Bannerth, Cs.

2009-01-01

The allowed condenser temperature of the condensing steam turbines is determined by the design parameters of the steam turbine (casing geometry, exhaust area, blade length, blade angle, blade profile etc.). The fluctuations of condenser temperature may lead to reduced power output of the condensing steam turbine. Solutions where the low pressure turbine casings have the same exhaust area can be kept in operation at narrow condenser temperature range without restrictions. Exceeding the mentioned temperature range the exhaust hood temperature restriction, undergoing the temperature range choking point restriction appears causing increased operation cost. The aim of the paper is to present a condensing steam turbine - direct-contact condenser system that can extend the unrestricted operating range. The examined system consists of more parallelly connected low pressure turbine casings so-called diabolo that having at least two exhausts separated at the steam side. The exhausts, utilizing varying input-temperature coolant, are connected to the condensers that are separated at the steam side and serially connected at the coolant side. The casings have the same inlet areas while the exhausts have different areas resulting different volume flows and temperature operating range. The economic advantage of this solution approaches the savings between the serially connected direct-contact condensers and condensers in parallel of a dry cooling system. It can be proven by a simple calculation using the ambient air temperature duration diagram that is presented in the paper. (author)

ORTAP: a nuclear steam supply system simulation for the dynamic analysis of high temperature gas cooled reactor transients

International Nuclear Information System (INIS)

Cleveland, J.C.; Hedrick, R.A.; Ball, S.J.; Delene, J.G.

1977-01-01

ORTAP was developed to predict the dynamic behavior of the high temperature gas cooled reactor (HTGR) Nuclear Steam Supply System for normal operational transients and postulated accident conditions. It was developed for the Nuclear Regulatory Commission (NRC) as an independent means of obtaining conservative predictions of the transient response of HTGRs over a wide range of conditions. The approach has been to build sufficient detail into the component models so that the coupling between the primary and secondary systems can be accurately represented and so that transients which cover a wide range of conditions can be simulated. System components which are modeled in ORTAP include the reactor core, a typical reheater and steam generator module, a typical helium circulator and circulator turbine and the turbine generator plant. The major plant control systems are also modeled. Normal operational transients which can be analyzed with ORTAP include reactor start-up and shutdown, normal and rapid load changes. Upset transients which can be analyzed with ORTAP include reactor trip, turbine trip and sudden reduction in feedwater flow. ORTAP has also been used to predict plant response to emergency or faulted conditions such as primary system depressurization, loss of primary coolant flow and uncontrolled removal of control poison from the reactor core

Method for operating a steam turbine of the nuclear type with electronic reheat control of a cycle steam reheater

International Nuclear Information System (INIS)

Luongo, M.C.

1975-01-01

An electronic system is provided for operating a nuclear electric power plant with electronic steam reheating control applied to the nuclear turbine system in response to low pressure turbine temperatures, and the control is adapted to operate in a plurality of different automatic control modes to control reheating steam flow and other steam conditions. Each of the modes of control permit turbine temperature variations within predetermined constraints and according to predetermined functions of time. (Official Gazette)

A system to control low pressure turbine temperatures

International Nuclear Information System (INIS)

1980-01-01

An improved system to control low pressure turbine cycle steam and metal temperatures by governing the heat transfer operation in a moisture separator-reheater is described. The use of the present invention in a pressurized water reactor or a boiling water reactor steam turbine system is demonstrated. (UK)

Analysis of flow instability in steam turbine control valves

International Nuclear Information System (INIS)

Pluviose, M.

1981-01-01

With the sponsorship of Electricite de France and the French steam turbine manufacturers, the Gas Turbine Laboratory of CETIM has started a research about the unsteady phenomena of flow in control valves of steam turbines. The existence of unsteady embossment in the valve cone at rise has been as certained, and a conventional computing procedure has been applied to locate the shock waves in the valve. These shock waves may suddenly arise at some valve lifts and give way to fluttering. Valve geometries attenuating instability of flow and increasing therefore the reliability of such equipment are proposed [fr

To the choice of the regeneration system of the K-1000-68/1500 turbine plant for the NPP with a vertical-type steam generator

International Nuclear Information System (INIS)

Kuznetsov, N.M.; Piskarev, A.A.; Grinman, M.I.; Kruglikov, P.A.

1985-01-01

Several variants of the heat regeneration system for the NPP with WWER-1000 type reactors using vertical steam generator (SG) generating saturated steam at 7.2 MPa pressure and 200 deg C feed water temperature at the SG inlet are considered. The results of comparison of variants in water and steam circuits of turbine plants are greatly influenced by integral economy account, i.e. efficiency indexes account under variable conditions of power unit operation. From variants of water and steam circuits of the K-1000-68/1500 turbine plant considered preference is given to the variant with four low pressure heaters with increased up to 1.25 MPa pressure in a deacrator without high pressure heater with pumping intermediate steam superheater condensate into feedwater circuit

Turbine protecting device in a BWR type nuclear power plant

International Nuclear Information System (INIS)

Kasuga, Hajime; Oka, Yoko.

1984-01-01

Purpose: To prevent highly humid steams from flowing into the turbine upon abnormal reduction in the reactor water level in order to ensure the turbine soundness, as well as in order to trip the turbine with no undesired effect on the reactor. Constitution: A protection device comprising a judging device and a timer are disposed in a BWR type reactor, in order to control a water level signal from a reactor water level gage. If the reactor water level is reduced during rated power operation, steams are kept to be generated due to decay heat although reactor is scramed. When a signal from the reactor water level detector is inputted to the protection device, a trip signal is outputted by way of a judging device after 15 second by means of the timer, when the main steam check valve is closed to trip the turbine. With this delay of time, abrupt increase in the pressure of the reactor due to sudden shutdown can be prevented. (Nakamoto, H)

Development history of the gas turbine modular high temperature reactor

International Nuclear Information System (INIS)

Brey, H.L.

2001-01-01

The development of the high temperature gas cooled reactor (HTGR) as an environmentally agreeable and efficient power source to support the generation of electricity and achieve a broad range of high temperature industrial applications has been an evolutionary process spanning over four decades. This process has included ongoing major development in both the HTGR as a nuclear energy source and associated power conversion systems from the steam cycle to the gas turbine. This paper follows the development process progressively through individual plant designs from early research of the 1950s to the present focus on the gas turbine modular HTGR. (author)

Thermal performance test for steam turbine of nuclear power plants

International Nuclear Information System (INIS)

Bu Yubing; Xu Zongfu; Wang Shiyong

2014-01-01

Through study of steam turbine thermal performance test of CPR1000 nuclear power plant, we solve the enthalpy calculation problems of the steam turbine in wet steam zone using heat balance method which can help to figure out the real overall heat balance diagram for the first time, and we develop a useful software for thermal heat balance calculation. Ling'ao phase II as an example, this paper includes test instrument layout, system isolation, risk control, data acquisition, wetness measurement, heat balance calculation, etc. (authors)

Concept of turbines for ultrasupercritical, supercritical, and subcritical steam conditions

Science.gov (United States)

Mikhailov, V. E.; Khomenok, L. A.; Pichugin, I. I.; Kovalev, I. A.; Bozhko, V. V.; Vladimirskii, O. A.; Zaitsev, I. V.; Kachuriner, Yu. Ya.; Nosovitskii, I. A.; Orlik, V. G.

2017-11-01

The article describes the design features of condensing turbines for ultrasupercritical initial steam conditions (USSC) and large-capacity cogeneration turbines for super- and subcritical steam conditions having increased steam extractions for district heating purposes. For improving the efficiency and reliability indicators of USSC turbines, it is proposed to use forced cooling of the head high-temperature thermally stressed parts of the high- and intermediate-pressure rotors, reaction-type blades of the high-pressure cylinder (HPC) and at least the first stages of the intermediate-pressure cylinder (IPC), the double-wall HPC casing with narrow flanges of its horizontal joints, a rigid HPC rotor, an extended system of regenerative steam extractions without using extractions from the HPC flow path, and the low-pressure cylinder's inner casing moving in accordance with the IPC thermal expansions. For cogeneration turbines, it is proposed to shift the upper district heating extraction (or its significant part) to the feedwater pump turbine, which will make it possible to improve the turbine plant efficiency and arrange both district heating extractions in the IPC. In addition, in the case of using a disengaging coupling or precision conical bolts in the coupling, this solution will make it possible to disconnect the LPC in shifting the turbine to operate in the cogeneration mode. The article points out the need to intensify turbine development efforts with the use of modern methods for improving their efficiency and reliability involving, in particular, the use of relatively short 3D blades, last stages fitted with longer rotor blades, evaporation techniques for removing moisture in the last-stage diaphragm, and LPC rotor blades with radial grooves on their leading edges.

Evaluation of Steam Generator Level behavior for Determination of Turbine Runback rate on COPs trip for Yonggwang 1 and 2 Power Uprating Units

International Nuclear Information System (INIS)

Lee, Kyung Jin; Hwang, Su Hyun; Yoo, Tae Geun; Chung, Soon Il; An, Byung Chang; Park, Jung Gu

2010-01-01

4.5% power uprate project has been progressing for the first time in Yonggwang 1 and 2(YGN1 and 2). Reviews for design change due to the power uprate were accomplished. Steam generator level behavior was one of the most important parameters because it could be cause of reactor trip or turbine trip. As the results of the reviews, YGN1 and 2 had to reassess it for change of turbine runback rate when turbine runback occurs due to the condensate operating pumps (COP) trip. This study has been carried out for evaluating the steam generator level behavior for determination of turbine runback rate on COPs trip for Yonggwang 1 and 2 Power Uprating Units. The steam generator water level evaluation program for YGN1 and 2 (SLEP-Y1) has been developed for it. The program includes models for the steam generator water level response. SLEP-Y1 is programmed with advanced continuous system simulation language (ACSL). The language has been used to simulate physical systems as a commercial tool used to evaluate system designs

Preliminary safety evaluation of the Gas Turbine-Modular Helium Reactor (GT-MHR)

International Nuclear Information System (INIS)

Dunn, T.D.; Lommers, L.J.; Tangirala, V.E.

1994-04-01

A qualitative comparison between the safety characteristics of the Gas Turbine-Modular Helium Reactor (GT-MHR) and those of the steam cycle shows that the two designs achieve equivalent levels of overall safety performance. This comparison is obtained by applying the scaling laws to detailed steam-cycle computations as well as the conclusions obtained from preliminary GT-MHR model simulations. The gas turbine design is predicted to be superior for some event categories, while the steam cycle design is better for others. From a safety perspective, the GT-MHR has a modest advantage for pressurized conduction cooldown events. Recent computational simulations of 102 column, 550 MW(t) GT-MHR during a depressurized conduction cooldown show that peak fuel temperatures are within the limits. The GT-MHR has a significantly lower risk due to water ingress events under operating conditions. Two additional scenarios, namely loss of load event and turbine deblading event that are specific to the GT-MHR design are discussed. Preliminary evaluation of the GT-MHR's safety characteristics indicate that the GT-MHR can be expected to satisfy or exceed its safety requirements

Postfact phenomena of the wet-steam flow electrization in turbines

Science.gov (United States)

Tarelin, A. A.

2017-11-01

Physical processes occurring in a turbine with natural electrization of a humidity-steam flow and their effect on efficiency and reliability of the turbine operation has been considered. Causes of the electrical potential occurrence on a rotor shaft are analyzed. The wet steam's electrization exposure on the electrical potential that is one of the major factors of bearings' electroerosion has been demonstrated on the full-scale installation. Hydrogen formation in wheelspace of the turbine as a result of electrochemical processes and electric field exposure of the space charge has been considered. Hydrogen concentration dependence on a volume charge density in the steam flow has been determined. It is stated that the processes occurring behind the final stage of wet-steam turbines are similar to the ones in elaerosol ectrostatic generators. It has been demonstrated that this phenomenon causes the flow's temporal inhibition and starts pulsations. These factors' impact on power loss of the turbine has been evaluated and recommendations for their elimination have been offered. It has been determined that motions of charged drops can cause self-maintained discharges inside of the flow and between the flow and grounded surfaces that are accompanied by electromagnetic radiation of the wide spectrum. The integrated studies have shown that physical phenomena occurring due to natural electrization negatively affect efficiency and reliability of the turbine operation. Practical recommendations allowing one to minimize the negative effects of the flow natural electrization process have been offered.

Evaluation of anticipatory signal to steam generator pressure control program for 700 MWe Indian pressurized heavy water reactor

International Nuclear Information System (INIS)

Pahari, S.; Hajela, S.; Rammohan, H. P.; Malhotra, P. K.; Ghadge, S. G.

2012-01-01

700 MWe Indian Pressurized Heavy Water Reactor (IPHWR) is horizontal channel type reactor with partial boiling at channel outlet. Due to boiling, it has a large volume of vapor present in the primary loops. It has two primary loops connected with the help of pressurizer surge line. The pressurizer has a large capacity and is partly filled by liquid and partly by vapor. Large vapor volume improves compressibility of the system. During turbine trip or load rejection, pressure builds up in Steam Generator (SG). This leads to pressurization of Primary Heat Transport System (PHTS). To control pressurization of SG and PHTS, around 70% of the steam generated in SG is dumped into the condenser by opening Condenser Steam Dump Valves (CSDVs) and rest of the steam is released to the atmosphere by opening Atmospheric Steam Discharge Valves (ASDVs) immediately after sensing the event. This is accomplished by adding anticipatory signal to the output of SG pressure controller. Anticipatory signal is proportional to the thermal power of reactor and the proportionality constant is set so that SG pressure controller's output jacks up to ASDV opening range when operating at 100% FP. To simulate this behavior for 700 MWe IPHWR, Primary and secondary heat transport system is modeled. SG pressure control and other process control program have also been modeled to capture overall plant dynamics. Analysis has been carried out with 3-D neutron kinetics coupled thermal hydraulic computer code ATMIKA.T to evaluate the effect of the anticipatory signal on PHT pressure and over all plant dynamics during turbine trip in 700 MWe IPHWR. This paper brings out the results of the analysis with and without considering anticipatory signal in SG pressure control program during turbine trip. (authors)

Steam Turbine Flow Path Seals (a Review)

Science.gov (United States)

Neuimin, V. M.

2018-03-01

Various types of shroud, diaphragm, and end seals preventing idle leak of working steam are installed in the flow paths of steam turbine cylinders for improving their efficiency. Widely known labyrinth seals are most extensively used in the Russian turbine construction industry. The category of labyrinth seals also includes seals with honeycomb inserts. The developers of seals with honeycomb inserts state that the use of such seals makes it possible to achieve certain gain due to smaller leaks of working fluid and more reliable operation of the system under the conditions in which the rotor rotating parts may rub against the stator elements. However, a positive effect can only be achieved if the optimal design parameters of the honeycomb structure are fulfilled with due regard to the specific features of its manufacturing technology and provided that this structure is applied in a goal-seeking manner in the seals of steam and gas turbines and compressors without degrading their vibration stability. Calculated and preliminary assessments made by experts testify that the replacement of conventional labyrinth seals by seals with honeycomb inserts alone, due to which the radial gaps in the shroud seal can be decreased from 1.5 to 0.5 mm, allows the turbine cylinder efficiency to be increased at the initial stage by approximately 1% with the corresponding gain in the turbine set power output. The use of rectangular-cellular seals may result, according to estimates made by their developers, in a further improvement of turbine efficiency by 0.5-1.0%. The labor input required to fabricate such seals is six to eight times smaller than that to fabricate labyrinth seals with honeycomb inserts. Recent years have seen the turbine construction companies of the United States and Germany advertising the use of abradable (sealing) coatings (borrowed from the gas turbine construction technology) in the turbine designs instead of labyrinth seals. The most efficient performance of

Auxiliary water supply device for BWR type reactor

International Nuclear Information System (INIS)

Sasagawa, Hiroshi.

1994-01-01

In the device of the present invention, a cooling condensation means is disposed to a steam discharge channel of a turbine for driving pumps to directly return condensates to the reactor, so that the temperature of the suppression pool water is not elevated. Namely, the cooling condensation means for discharged steams is disposed to the discharge channel of the turbine. The condensate channel from the cooling condensation means is connected to a sucking side of the turbine driving pump. With such a constitution, when the reactor is isolated from a main steam system, reactor scram is conducted. Although the reactor water level is lowered by the reactor scram, the lowering of the reactor water level is prevented by supplementing cooling water by the turbine driving pump using steams generated in the reactor as a power source. The discharged steams after driving the turbine are cooled and condensated by the cooling condensation means by way of the discharge channel and returned to the reactor again by way of the condensate channel. With such procedures, since the temperature of suppression pool water is not elevated, there is no need to operate other cooling systems. In addition, auxiliary water can be supplied for a long period of time. (I.S.)

Calculations of the nozzle coefficient of discharge of wet steam turbine stages

International Nuclear Information System (INIS)

Jinling, Z.; Yinian, C.

1989-01-01

A method is presented for calculating the coefficient of discharge of wet steam turbine nozzles. The theoretical formulation of the problem is rigorously in accordance with the theory of two-phase wet steam expansion flow through steam turbine nozzles. The computational values are plotted as sets of curves in accordance with orthogonality test principles. They agree satisfactorily both with historical empirical data and the most recent experimental data obtained in the wet steam two-phase flow laboratory of Xian Jiaotong University. (author)

Engineering nonlinearity characteristic compensation for commercial steam turbine control valve using linked MARS code and Matlab Simulink

International Nuclear Information System (INIS)

Halimi, B.; Suh, Kune Y.

2012-01-01

Highlights: ► A nonlinearity characteristic compensation is proposed of the steam turbine control valve. ► A steady state and transient analyzer is developed of Ulchin Units 3 and 4 OPR1000 nuclear plants. ► MARS code and Matlab Simulink are used to verify the compensation concept. ► The results show the concept can compensate for the nonlinearity characteristic very well. - Abstract: Steam turbine control valves play a pivotal role in regulating the output power of the turbine in a commercial power plant. They thus have to be operated linearly to be run by an automatic control system. Unfortunately, the control valve has inherently nonlinearity characteristics. The flow increases more significantly near the closed end than near the open end of the stem travel given the valve position signal. The steam flow should nonetheless be proportional to the final desired quantity, output power, of the turbine to obtain a linear operation. This paper presents the valve engineering linked analysis (VELA) for nonlinearity characteristic compensation of the steam turbine control valve by using a linked two existing commercial software. The Multi-dimensional Analysis of Reactor Safety (MARS) code and Matlab Simulink have been selected for VELA to develop a steady state and transient analyzer of Ulchin Units 3 and 4 powered by the Optimized Power Reactor 1000 MWe (OPR1000). MARS is capable of modeling a wide range of systems from single pipes to full nuclear power plants. As one of standard nuclear power plant thermal hydraulic analysis software tools, MARS simulates the primary and secondary sides of the nuclear power plant. To simulate the electric power flow part, Matlab Simulink is chosen as the standard analysis software. Matlab Simulink having an interactive environment to model analyzes and simulates a wide variety of engineering dynamic systems including multimachine power systems. Based on the MARS code result, Matlab Simulink analyzes the power flow of the

Two different modelling methods of the saturated steam turbine load rejection

International Nuclear Information System (INIS)

Negreanu, Gabriel-Paul; Oprea, Ion

1999-01-01

One of the most difficult operation regimes of a steam turbine is the load rejection. It happens usually when the main switchgear of the unit closes unexpectedly due to some external or internal causes. In this moment, the rotor balance collapses: the motor momentum is positive, the resistant momentum is zero and the rotation velocity increases rapidly. When this process occurs, the over-speed protection should activate the emergency stop valves and the control and intercept valves in order to stop the steam admission into the turbine. The paper presents two differential approaches of the fluid dynamic processes from the flow sections of the saturated steam turbine of the NPP, where the laws of mass and energy conservation are applied. In this manner, the 'power and speed versus time' diagrams can be drawn. The main parameters of such technical problem are the closure low of the valves, the large volume of internal cavities, the huge inertial momentum of the rotor and especially the moisture of the steam that evaporates when the pressure decreases and generates an extra power in the turbine. (authors)

Development of 52 inch last stage blade for steam turbine

International Nuclear Information System (INIS)

Kadoya, Yoshiki; Harada, Masakatsu; Watanabe, Eiichiro

1985-01-01

Mitsubishi Heavy Industries, Ltd. has developed the last stage blades with 1320 mm length for a 1800 rpm LP turbine, and the verification by rotating vibration test using actual blades was finished, thus the blades were completed. In a nuclear power plant with an A-PWR of 3800 MW thermal output, the 1350 MW steam turbine has one HP turbine and three LP turbines coupled in tandem, and the optimum last stage blades for the LP turbines became the 1320 mm blades. The completion of these blades largely contributes to the improvement of thermal efficiency and the increase of generator output in large nuclear power plants, and has the possibility to decrease three LP turbines to two in 900 MW plants, which reduces the construction cost. The velocity energy of steam coming out of last stage blades is abandoned as exhaust loss in a condenser, which is the largest loss in a turbine. The increase of exhaust area using long blades reduces this loss. The economy of the 1320 mm blades, the features of the 1320 mm blades, the aerodynamic design and its verification, the prevention of the erosion of the 1320 mm blades due to wet steam, the strength design, the anti-vibration design and its verification, and the CAD/CAM system are reported. (Kako, I.)

Endoscopic inspection of steam turbines

International Nuclear Information System (INIS)

Maliniemi, H.; Muukka, E.

1990-01-01

For over ten years, Imatran Voima Oy (IVO) has developed, complementary inspection methods for steam turbine condition monitoring, which can be applied both during operation and shutdown. One important method used periodically during outages is endoscopic inspection. The inspection is based on the method where the internal parts of the turbine is inspected through access borings with endoscope and where the magnified figures of the internal parts is seen on video screen. To improve inspection assurance, an image-processing based pattern recognition method for cracks has been developed for the endoscopic inspection of turbine blades. It is based on the deduction conditions derived from the crack shape. The computer gives an alarm of a crack detection and prints a simulated image of the crack, which is then checked manually

Investigation of brush seals for application in steam turbines

International Nuclear Information System (INIS)

Zorn, Peter

2012-01-01

Brush seals have high potential for efficiency increase compared to conventional labyrinth seals in steam turbines. Due to less experience in operation today there is a lot of scepticism with customers of steam turbine manufacturers. Therefore this thesis is investigating characteristics of this type of seal. Experiments and numerical models will be presented, which lead to better knowledge about leakages and influence of flow through seal onto dynamics of rotor in comparison to labyrinth seals. This thesis is increasing area of experience and one more positive reference.

Boresonic inspection of steam turbine and generator spindles with the Tomoscan

International Nuclear Information System (INIS)

Dube, N.; Bertholotti, D.; Yates, D.

1990-01-01

Steam turbine rotors in power utility plants can generate cracks and ultimately fail after long period of use. The inspection of rotors is done on a regular basis and particular attention is paid to areas near bore holes. An automated ultrasound system has been developed to control and ensure the quality of rotor bore holes of steam turbine rotors

Multi-layer casing of a steam turbine for high steam pressures and temperatures

International Nuclear Information System (INIS)

Remberg, A.

1978-01-01

In previous turbine casings there is no sealing provided between the inner layer and the outer layer, so that the steam pressure acts fully on the casing top and on the shaft seal housing situated there. To reduce the displacement which occurs there due to pressure differences in the various steam spaces, the normal inner casing is made with the shaft sealing housing in an inner layer, which cannot be divided in the axial direction. The inner layer can be inserted from the high pressure side into the unit outer casing. A horizontal section through the turbine in the attached drawing makes the construction and operation of the invention clear. (GL) [de

ULTRA SCWR+: Practical advanced water reactor concepts

International Nuclear Information System (INIS)

Duffey, Romney; Khartabil, Hussam; Kuran, Sermet; Zhou, Tracy; Pioro, Igor

2008-01-01

Modern thermal power plants now utilize supercritical steam cycles with thermal efficiencies of over 45%. Recent developments have lead to Ultra-SuperCritical (USC) systems, which adopt reheat turbines that can attain efficiencies of over 50%. Because these turbines are already developed, demonstrated and deployed worldwide, and use existing and traditional steam cycle technology, the simplest nuclear advance is to utilize these proven thermal cycle conditions by coupling this turbine type to a reactor. This development direction is fundamentally counter to the usual approach of adopting high-temperature gas-cooled (helium-cooled) reactor cycles, for which turbines have yet to be demonstrated on commercial scale unlike the supercritical steam turbines. The ULTRA (Ultra-supercritical Light water Thermal ReActor) SCWR+ concept adopts the fundamental design approach of matching a water and steam-cooled reactor to the ultra-supercritical steam cycle, adopting the existing and planned thermal power plant turbines. The HP and IP sections are fed with conditions of 25 MPa/625degC and 7 MPa/700degC, respectively, to achieve operating plant thermal efficiencies in excess of 50%, with a direct turbine cycle. By using such low-pressure reheated steam, this concept also adopts technology that was explored and used many years ago in existing water reactors, with the potential to produce large quantities of low cost heat, which can be used for other industrial and district processes. Pressure-Tube (PT) reactors are suitable for adoption of this design approach and, in addition, have other advantages that will significantly improve water-cooled reactor technology. These additional advantages include enhanced safety and improved resource utilization and proliferation resistance. This paper describes the PT-SCWR+ concept and its potential enhancements. (author)

PORST: a computer code to analyze the performance of retrofitted steam turbines

Energy Technology Data Exchange (ETDEWEB)

Lee, C.; Hwang, I.T.

1980-09-01

The computer code PORST was developed to analyze the performance of a retrofitted steam turbine that is converted from a single generating to a cogenerating unit for purposes of district heating. Two retrofit schemes are considered: one converts a condensing turbine to a backpressure unit; the other allows the crossover extraction of steam between turbine cylinders. The code can analyze the performance of a turbine operating at: (1) valve-wide-open condition before retrofit, (2) partial load before retrofit, (3) valve-wide-open after retrofit, and (4) partial load after retrofit.

Imitative modeling automatic system Control of steam pressure in the main steam collector with the influence on the main Servomotor steam turbine

Science.gov (United States)

Andriushin, A. V.; Zverkov, V. P.; Kuzishchin, V. F.; Ryzhkov, O. S.; Sabanin, V. R.

2017-11-01

The research and setting results of steam pressure in the main steam collector “Do itself” automatic control system (ACS) with high-speed feedback on steam pressure in the turbine regulating stage are presented. The ACS setup is performed on the simulation model of the controlled object developed for this purpose with load-dependent static and dynamic characteristics and a non-linear control algorithm with pulse control of the turbine main servomotor. A method for tuning nonlinear ACS with a numerical algorithm for multiparametric optimization and a procedure for separate dynamic adjustment of control devices in a two-loop ACS are proposed and implemented. It is shown that the nonlinear ACS adjusted with the proposed method with the regulators constant parameters ensures reliable and high-quality operation without the occurrence of oscillations in the transient processes the operating range of the turbine loads.

Improvements to PWR type reactors

International Nuclear Information System (INIS)

Ailloud, Jean; Monteil, Marcel.

1978-01-01

Improvements to pressurized water nuclear reactors are described, where the core coolant, called primary fluid, flows under the effect of a circulating pump in a primary loop between a steam generator and a pressure vessel containing the reactor core. The steam generator includes a bundle of tubes through which flows the primary fluid which exchanges calories with a secondary fluid, generally water, entering the generator as a liquid and issuing from it as steam. After expansion in turbines and recovery in a condenser, this steam is returned to the inside of the generator. Each primary fluid circulating pump is powered by a back-pressure turbine located in parallel with the high pressure section of the main turbine and hence fed with steam taken directly from the steam generator or the main steam pipe outside it [fr

Nuclear steam power plant cycle performance calculations supported by power plant monitoring and results computer

International Nuclear Information System (INIS)

Bettes, R.S.

1984-01-01

The paper discusses the real time performance calculations for the turbine cycle and reactor and steam generators of a nuclear power plant. Program accepts plant measurements and calculates performance and efficiency of each part of the cycle: reactor and steam generators, turbines, feedwater heaters, condenser, circulating water system, feed pump turbines, cooling towers. Presently, the calculations involve: 500 inputs, 2400 separate calculations, 500 steam properties subroutine calls, 200 support function accesses, 1500 output valves. The program operates in a real time system at regular intervals

Microfabricated rankine cycle steam turbine for power generation and methods of making the same

Science.gov (United States)

Frechette, Luc (Inventor); Muller, Norbert (Inventor); Lee, Changgu (Inventor)

2009-01-01

In accordance with the present invention, an integrated micro steam turbine power plant on-a-chip has been provided. The integrated micro steam turbine power plant on-a-chip of the present invention comprises a miniature electric power generation system fabricated using silicon microfabrication technology and lithographic patterning. The present invention converts heat to electricity by implementing a thermodynamic power cycle on a chip. The steam turbine power plant on-a-chip generally comprises a turbine, a pump, an electric generator, an evaporator, and a condenser. The turbine is formed by a rotatable, disk-shaped rotor having a plurality of rotor blades disposed thereon and a plurality of stator blades. The plurality of stator blades are interdigitated with the plurality of rotor blades to form the turbine. The generator is driven by the turbine and converts mechanical energy into electrical energy.

Efficiency calculation on 10 MW experimental steam turbine

Directory of Open Access Journals (Sweden)

Hoznedl Michal

2018-01-01

Full Text Available The paper deals with defining flow path efficiency of an experimental steam turbine by using measurement of flow, torque, pressures and temperatures. The configuration of the steam turbine flow path is briefly described. Measuring points and devices are defined. The paper indicates the advantages as well as disadvantages of flow path efficiency measurement using enthalpy and torque on the shaft. The efficiency evaluation by the help pressure and temperature measurement is influenced by flow parameter distribution and can provide different values of flow path efficiency. The efficiency determination by using of torque and mass flow measurement is more accurate and it is recommended for using. The disadvantage is relatively very complicated and expensive measuring system.

Unsteady coupling effects of wet steam in steam turbines flows

International Nuclear Information System (INIS)

Blondel, Frederic

2014-01-01

In addition to conventional turbomachinery problems, both the behavior and performances of steam turbines are highly dependent on the vapour thermodynamic state and the presence of a liquid phase. EDF, the main French electricity producer, is interested in further developing its' modelling capabilities and expertise in this area to allow for operational studies and long-term planning. This PhD thesis explores the modelling of wetness formation and growth in a steam turbine and an analysis of the coupling between the liquid phase and the main flow unsteadiness. To this end, the work in this thesis took the following approach. Wetness was accounted for using a homogeneous model coupled with transport equations to take into account the effects of non-equilibrium phenomena, such as the growth of the liquid phase and nucleation. The real gas attributes of the problem demanded adapted numerical methods. Before their implementation in the 3D elsA solver, the accuracy of the chosen models was tested using a developed one-dimensional nozzle code. In this manner, various condensation models were considered, including both poly-dispersed and monodispersed behaviours of the steam. Finally, unsteady coupling effects were observed from several perspectives (1D, 1D - 3D, 3D), demonstrating the ability of the method of moments to sustain unsteady phenomena which were not apparent in a simple monodispersed model. (author)

The gas turbine-modular helium reactor (GT-MHR), high efficiency, cost competitive, nuclear energy for the next century

International Nuclear Information System (INIS)

Zgliczynski, J.B.; Silady, F.A.; Neylan, A.J.

1994-04-01

The Gas Turbine-Modular Helium Reactor (GT-MHR) is the result of coupling the evolution of a small passively safe reactor with key technology developments in the US during the last decade: large industrial gas turbines, large active magnetic bearings, and compact, highly effective plate-fin heat exchangers. The GT-MHR is the only reactor concept which provides a step increase in economic performance combined with increased safety. This is accomplished through its unique utilization of the Brayton cycle to produce electricity directly with the high temperature helium primary coolant from the reactor directly driving the gas turbine electrical generator. This cannot be accomplished with another reactor concept. It retains the high levels of passive safety and the standardized modular design of the steam cycle MHTGR, while showing promise for a significant reduction in power generating costs by increasing plant net efficiency to a remarkable 47%

Development of 1800 rpm, 43in. blade for large steam turbine

International Nuclear Information System (INIS)

Kuroda, Michio; Yamazaki, Yoshiaki; Namura, Kiyoshi; Taki, Takamitsu; Ninomiya, Satoshi.

1978-01-01

In the turbines for nuclear power generation, the inlet conditions of steam is low pressure and low temperature as compared with the turbines for thermal power generation, therefore generally the required steam flow rate is much more. It is the main problem to cope with this steam of large flow rate effectively with long final stage blades and to make a turbine compact. This newly developed blade aims at the turbines from 1100 to 1300 MW class for nuclear power generation and those of 1000 MW class for thermal power generation, and it is the first low revolution, long blade in Japan used for large capacity machines of 60 Hz. Hereinafter, the outline of various examinations carried out at the time of the tests on this blade and the features of this blade are described. There is large margin in the exhaust area with this blade, therefore the turbines with large power output and good performance can be produced. The loss of exhaust energy at turbine exit can be reduced, and thermal efficiency can be raised. Large capacity machines from 1100 to 1300 MW class can be manufactured with six-flow exhaust, tandem compound turbines. In order to confirm the reliability, the vibration characteristics of the blade were investigated in the test of this time, and also the overspeed test and endurance test were carried out. (Kako, I.)

Influence of the loop design of the feedwater- and steam quality in a power plant with pressurized water reactor

International Nuclear Information System (INIS)

Bennert, J.; Becher, L.

1977-01-01

At nuclear power plants with pressurized water reactors, condensate occurs on the high pressure part of the water-steam circuit, caused by the operation with low steam parameters. The behaviour of the electrolytes which entered into the circuit (solubility, distribution in water and/or steam) shows that these electrolytes (salts) are to be found mainly in the condensate. The insinuated electrolytes are reconcentrated during the common arrangements with 'Small Circuit' - consisting of steam generator, high pressure turbine, water separator, feedwater vessel, and have a negative influence on the feedwater - boiler water - and the steam quality. Remedy is possible by modified arrangements, during which these electrolyte-containing condensates will be treated and traced back into the main circuit. Nevertheless that the efficiency decrease is insignificant and additional efforts are necessary, a change over to these arrangements is recommendable, due to the fact that the feedwater quality, the boiler water quality, the steam quality in front of the turbine, and finally also the operational safety, as well as the availability will be improved. (orig.) [de

Steam separator-superheater with drawing of a fraction of the dried steam

International Nuclear Information System (INIS)

Bessouat, Roger; Marjollet, Jacques.

1976-01-01

This invention concerns a vertical separator-superheater of the steam from a high pressure expansion turbine before it is admitted to an expansion turbine at a lower pressure, by heat exchange with steam under a greater pressure, and drawing of a fraction of the dried steam before it is superheated. Such drawing off is necessary in the heat exchange systems of light water nuclear reactors. Its purpose is to provide a separator-superheater that provides an even flow of non superheated steam and a regular distribution of the steam to be superheated to the various superheating bundles, with a significantly uniform temperature of the casing, thereby preventing thermal stresses and ensuring a minimal pressure drop. The vertical separator-superheater of the invention is divided into several vertical sections comprising as from the central area, a separation area of the steam entrained water and a superheater area and at least one other vertical section with only a separation area of the steam entrained water [fr

Thermal analysis of heat and power plant with high temperature reactor and intermediate steam cycle

Directory of Open Access Journals (Sweden)

Fic Adam

2015-03-01

Full Text Available Thermal analysis of a heat and power plant with a high temperature gas cooled nuclear reactor is presented. The main aim of the considered system is to supply a technological process with the heat at suitably high temperature level. The considered unit is also used to produce electricity. The high temperature helium cooled nuclear reactor is the primary heat source in the system, which consists of: the reactor cooling cycle, the steam cycle and the gas heat pump cycle. Helium used as a carrier in the first cycle (classic Brayton cycle, which includes the reactor, delivers heat in a steam generator to produce superheated steam with required parameters of the intermediate cycle. The intermediate cycle is provided to transport energy from the reactor installation to the process installation requiring a high temperature heat. The distance between reactor and the process installation is assumed short and negligable, or alternatively equal to 1 km in the analysis. The system is also equipped with a high temperature argon heat pump to obtain the temperature level of a heat carrier required by a high temperature process. Thus, the steam of the intermediate cycle supplies a lower heat exchanger of the heat pump, a process heat exchanger at the medium temperature level and a classical steam turbine system (Rankine cycle. The main purpose of the research was to evaluate the effectiveness of the system considered and to assess whether such a three cycle cogeneration system is reasonable. Multivariant calculations have been carried out employing the developed mathematical model. The results have been presented in a form of the energy efficiency and exergy efficiency of the system as a function of the temperature drop in the high temperature process heat exchanger and the reactor pressure.

An opportunity for capacity up-rating of 1000 MW steam turbine plant in Kozloduy NPP

International Nuclear Information System (INIS)

Popov, D.

2005-01-01

In connection with earlier and forced decommissioning of the Kozloduy NPP units 1 - 4, an alternative has to be found in order to substitute these capacities. As a reasonable options, capacity up-rating of 1000 MW steam turbine plants without nuclear reactor thermal capacity increase, is investigated in the present study. The cooling water for these units is delivered by Danube river. The cooling water temperatures substantially decrease during the winter months. These changes create an opportunity for steam back end pressure reduction. It was found that when the cooling water temperature decreases from 15 0 C to 3 0 C, the steam back end pressure is on the decrease of from 3.92 kPa to 2.3 kPa. As a result capacity of the plant could be raised up to 50 MW without any substantial equipment and systems change

Nuclear reactors with auxiliary boiler circuit

International Nuclear Information System (INIS)

George, B.V.; Cook, R.K.

1976-01-01

A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

Thermal hydraulic aspects of steam drum level control philosophy for the natural circulation based heavy water reactor

International Nuclear Information System (INIS)

Gupta, S.K.; Gaikwad, A.J.; Kumar, Rajesh

2004-01-01

From safety considerations advanced nuclear reactors rely more and more on passive systems such as natural circulation for primary heat removal. A natural circulation based water reactor is relatively larger in size so as to reduce flow losses and channel type for proper flow distribution. From the size of steam drum considerations it has to be multi loop but has a common inlet header. Normally the turbine follows the reactor. This paper addresses the thermal hydraulic aspects of the steam drum pressure and level control philosophy for a four drum, natural circulation based, channel type boiling water advanced reactor. Three philosophies may be followed for drum control viz. individual drum control, one control drum approach and an average of all the four drums. For drum pressure control, the steam flow to the turbine is be regulated. A single point pressure control is better than individual drum pressure control. This is discussed in the paper. But the control point has to be at a place down steam the point where all steam line from individual drum meet. This may lead to different pressure in all the four drums depending on the power produced in the respective loops. The difference in pressure cannot be removed even if the four drums are directly connected through pipes. Also the pressure control scheme with/without interconnection is discussed. For level, the control of individual drum may not be normally possible because of common inlet header. As the frictional pressure drops in the large diameter downcomers are small as compared to elevation pressure drops, the level in all the steam drum tend to equalize. Consequently a single representative drum level may be chosen as a control variable for controlling level in all the four drums. But in case, where all the four loops are producing different powers and single point pressure control is effective, the scheme may not work satisfactorily. the level in a drum may depend on the power produced in the loop

Steam as turbine blade coolant: Experimental data generation

Energy Technology Data Exchange (ETDEWEB)

Wilmsen, B.; Engeda, A.; Lloyd, J.R. [Michigan State Univ., East Lansing, MI (United States)

1995-10-01

Steam as a coolant is a possible option to cool blades in high temperature gas turbines. However, to quantify steam as a coolant, there exists practically no experimental data. This work deals with an attempt to generate such data and with the design of an experimental setup used for the purpose. Initially, in order to guide the direction of experiments, a preliminary theoretical and empirical prediction of the expected experimental data is performed and is presented here. This initial analysis also compares the coolant properties of steam and air.

Elimination of feedwater heaters in steam turbines: Prospects for substantial energy savings

International Nuclear Information System (INIS)

Lorenzoni, G.

1992-01-01

This paper re-proposes the theory that thermal regeneration (RT) in steam turbine plants decreases thermodynamic efficiency. This theory is supported by the criterion of maximization of variation of exergy in the steam generator (CMVEG) and by an mathematical argumentation based on the first law of thermodynamics. Consequences of great importance are deduced: plant operating costs reductions and a new possibility for cogeneration, that indicates exceptional advantages for the whole power industry, since steam turbine plants are responsible for the greater part of global electric power production

Multi-objective PID Optimization for Speed Control of an Isolated Steam Turbine using Gentic Algorithm

OpenAIRE

Sanjay Kr. Singh; D. Boolchandani; S.G. Modani; Nitish Katal

2014-01-01

This study focuses on multi-objective optimization of the PID controllers for optimal speed control for an isolated steam turbine. In complex operations, optimal tuning plays an imperative role in maintaining the product quality and process safety. This study focuses on the comparison of the optimal PID tuning using Multi-objective Genetic Algorithm (NSGA-II) against normal genetic algorithm and Ziegler Nichols methods for the speed control of an isolated steam turbine. Isolated steam turbine...

Development of 52 inches last stage blade for steam turbines

International Nuclear Information System (INIS)

Suzuki, Atsuhide; Hisa, Shoichi; Nagao, Shinichiro; Ogata, Hisao

1986-01-01

The last stage blades of steam turbines are the important component controlling the power output and performance of plants. In order to realize a unit of large capacity and high efficiency, the proper exhaust area and the last stage blades having good performance are indispensable. Toshiba Corp. has completed the development of the 52 inch last stage blades for 1500 and 1800 rpm steam turbines. The 52 inch last stage blades are the longest in the world, which have the annular exhaust area nearly 1.5 times as much as that of 41 inch blades used for 1100 MW, 1500 rpm turbines in nuclear power stations. By adopting these 52 inch blades, the large capacity nuclear power plants up to 1800 MW can be economically constructed, the rate of heat consumption of 1350 MW plants is improved by 3 ∼ 4 % as compared with 41 inch blades, and in the plants up to 1100 MW, LP turbines can be reduced from three sets to two. The features of 52 inch blades, the flow pattern and blade form design, the structural strength analysis and the erosion withstanding property, and the verification by the rotation test of the actual blades, the performance test using a test turbine, the vibration analysis of the actually loaded blades and the analysis of wet steam behavior are reported. (Kako, I.)

Turbine steam path replacement at the Grafenrheinfeld Nuclear Power Station

International Nuclear Information System (INIS)

Weschenfelder, K.D.; Oeynhausen, H.; Bergmann, D.; Hosbein, P.; Termuehlen, H.

1994-01-01

In the last few years, replacement of old vintage steam turbine flow path components has been well established as a valid approach to improve thermal performance of aged turbines. In nuclear power plants, performance improvement is generally achieved only by design improvements since performance deterioration of old units is minor or nonexistent. With fossil units operating over decades loss in performance is an additional factor which can be taken into account. Such loss of performance can be caused by deposits, solid particle erosion, loss of shaft and inter-stage seal strips, etc. Improvement of performance is typically guaranteed as output increases for operation at full load. This value can be evaluated as a direct gain in unit capacity without fuel or steam supply increase. Since fuel intake does not change, the relative improvement of the net plant heat rate or efficiency is equal to the relative increase in output. The heat rate improvement is achieved not only at full load but for the entire load range. Such heat rate improvement not only moves a plant up on the load dispatch list increasing its capacity factor, but also extensive fuel savings can pay off for the investment cost of new steam path components. Another important factor is that quite often older turbine designs show a deterioration of their reliability and need costly repairs. With new flow path components an aged steam turbine starts a new useful life

Optimization of Design of Steam Turbine Exhaust Conduits

Directory of Open Access Journals (Sweden)

A. S. Goldin

2014-01-01

Full Text Available Improving effectiveness turbine was and remains a key issue for today. In order to improve the efficiency of the turbine is necessary to reduce losses in the steam turbine exhaust conduit.This paper presents the design optimization exhaust conduit steam turbine K-27-2.9 produced by JSC «KTW» at the design stage. The aims of optimizing the design were: decreasing hydraulic resistance of the conduit, reduction of non-uniformity of the flow at the outlet of the conduit, equalizing steam flow ahead of the condenser tube bundle.The conduit models were made and flows in it were simulated in environment of the Solid Works and its application COSMOS Flo Works.As the initial conduit model was selected exhaust conduit of turbine PT-25/34-3.4 produced by JSC «KTW». Was obtained by the calculated velocity field at the outlet of the conduit. The analysis of the calculation results revealed the necessity of changes to the initial design of the conduit. The changes were accompanied by calculating currents flow in the conduit, and assessed the impact of design changes on the nature of the course. Further transformation of the construction of the conduit was held on the results of these calculations. Construction changes are not touched by the outer geometry of the conduit, and were introduced to meet technological.According to calculation results, conclusions were drawn and selected three versions of the conduit.Given are the research results for the initial conduit model and modified design versions. In order to evaluate the flow degree of irregularity the momentum factor (Bussinesku factor for outlet crosssection of the selected conduit design version. Analysis of the research results made it possible to determine optimum design of the exhaust conduit.Introducing the suggested alterations in the conduit design will result in improvement of heat exchange in the condenser, an increase in reliability of the tube bundle operation, a decrease in noise and

An expert system for diagnostics and estimation of steam turbine components condition

Science.gov (United States)

Murmansky, B. E.; Aronson, K. E.; Brodov, Yu. M.

2017-11-01

The report describes an expert system of probability type for diagnostics and state estimation of steam turbine technological subsystems components. The expert system is based on Bayes’ theorem and permits to troubleshoot the equipment components, using expert experience, when there is a lack of baseline information on the indicators of turbine operation. Within a unified approach the expert system solves the problems of diagnosing the flow steam path of the turbine, bearings, thermal expansion system, regulatory system, condensing unit, the systems of regenerative feed-water and hot water heating. The knowledge base of the expert system for turbine unit rotors and bearings contains a description of 34 defects and of 104 related diagnostic features that cause a change in its vibration state. The knowledge base for the condensing unit contains 12 hypotheses and 15 evidence (indications); the procedures are also designated for 20 state parameters estimation. Similar knowledge base containing the diagnostic features and faults hypotheses are formulated for other technological subsystems of turbine unit. With the necessary initial information available a number of problems can be solved within the expert system for various technological subsystems of steam turbine unit: for steam flow path it is the correlation and regression analysis of multifactor relationship between the vibration parameters variations and the regime parameters; for system of thermal expansions it is the evaluation of force acting on the longitudinal keys depending on the temperature state of the turbine cylinder; for condensing unit it is the evaluation of separate effect of the heat exchange surface contamination and of the presence of air in condenser steam space on condenser thermal efficiency performance, as well as the evaluation of term for condenser cleaning and for tube system replacement and so forth. With a lack of initial information the expert system enables to formulate a diagnosis

Energetic and exergetic analysis of a steam turbine power plant in an existing phosphoric acid factory

International Nuclear Information System (INIS)

Hafdhi, Fathia; Khir, Tahar; Ben Yahyia, Ali; Ben Brahim, Ammar

2015-01-01

Highlights: • The operating mode of the factory and the power supply streams are presented. • Energetic Analysis of steam turbine power plant of an existing phosphoric acid factory. • Exergetic Analysis of each component of steam turbine power plant and the different heat recovery system. • Energy, exergy efficiency and irreversibility rates for the main components are determined. • The effect of the operating parameters on the plant performance are analyzed. - Abstract: An energetic and exergetic analysis is conducted on a Steam Turbine Power Plant of an existing Phosphoric Acid Factory. The heat recovery systems used in the different parts of the plant are also considered in the study. Mass, energy and exergy balances are established on the main compounds of the plant. A numerical code is established using EES software to perform the calculations required for the thermal and exergy plant analysis considering real variation ranges of the main operating parameters such as pressure, temperature and mass flow rate. The effects of theses parameters on the system performances are investigated. The main sources of irreversibility are the melters, followed by the heat exchangers, the steam turbine generator and the pumps. The maximum energy efficiency is obtained for the blower followed by the heat exchangers, the deaerator and the steam turbine generator. The exergy efficiency obtained for the heat exchanger, the steam turbine generator, the deaerator and the blower are 88%, 74%, 72% and 66% respectively. The effects of High Pressure steam temperature and pressure on the steam turbine generator energy and exergy efficiencies are investigated.

STYLE, Steam Cycle Heat Balance for Turbine Blade Design in Marine Operation

International Nuclear Information System (INIS)

Love, J.B.; Dines, W.R.

1970-01-01

1 - Nature of physical problem solved: The programme carries out iterative steam cycle heat balance calculations for a wide variety of steam cycles including single reheat, live steam reheat and multistage moisture separation. Facilities are also available for including the steam-consuming auxiliaries associated with a marine installation. Though no attempt is made to carry out a detailed turbine blading design the programme is capable of automatically varying the blading efficiency from stage to stage according to local steam volume flow rate, dryness fraction and shaft speed. 2 - Method of solution: 3 - Restrictions on the complexity of the problem: Steam pressures to lie within range 0.2 to 5,000 lb/square inch abs steam temperatures to lie within range 50 to 1600 degrees F. Not more than 40 points per turbine expansion line; Not more than 10 expansion lines; Not more than 15 feed heaters. UNIVAC 1108 version received from FIAT Energia Nucleare, Torino, Italy

Modeling and optimization of a utility system containing multiple extractions steam turbines

International Nuclear Information System (INIS)

Luo, Xianglong; Zhang, Bingjian; Chen, Ying; Mo, Songping

2011-01-01

Complex turbines with multiple controlled and/or uncontrolled extractions are popularly used in the processing industry and cogeneration plants to provide steam of different levels, electric power, and driving power. To characterize thermodynamic behavior under varying conditions, nonlinear mathematical models are developed based on energy balance, thermodynamic principles, and semi-empirical equations. First, the complex turbine is decomposed into several simple turbines from the controlled extraction stages and modeled in series. THM (The turbine hardware model) developing concept is applied to predict the isentropic efficiency of the decomposed simple turbines. Stodola's formulation is also used to simulate the uncontrolled extraction steam parameters. The thermodynamic properties of steam and water are regressed through linearization or piece-wise linearization. Second, comparison between the simulated results using the proposed model and the data in the working condition diagram provided by the manufacturer is conducted over a wide range of operations. The simulation results yield small deviation from the data in the working condition diagram where the maximum modeling error is 0.87% among the compared seven operation conditions. Last, the optimization model of a utility system containing multiple extraction turbines is established and a detailed case is analyzed. Compared with the conventional operation strategy, a maximum of 5.47% of the total operation cost is saved using the proposed optimization model. -- Highlights: → We develop a complete simulation model for steam turbine with multiple extractions. → We test the simulation model using the performance data of commercial turbines. → The simulation error of electric power generation is no more than 0.87%. → We establish a utility system operational optimization model. → The optimal industrial operation scheme featured with 5.47% of cost saving.

Conceptual design of a hydrogen production system by DME steam reforming and high-efficiency nuclear reactor technology

International Nuclear Information System (INIS)

Fukushima, Kimichika; Ogawa, Takashi

2003-01-01

Hydrogen is a potential alternative energy source and produced commercially by methane (natural gas) or LPG steam reforming, a process that requires high temperatures, which are produced by burning fossil fuels. However, since this process emits large amounts of CO 2 , replacement of the combustion heat source with a nuclear heat source for 773-1173 K processes has been proposed in order to eliminate these CO 2 emissions. This paper proposes a novel method of low-temperature nuclear hydrogen production by reforming dimethyl ether (DME) with steam produced by a low-temperature nuclear reactor at about 573 K. The authors identified conditions that provide high hydrogen production fraction at low pressure and temperatures of about 523-573 K. By setting this low-temperature hydrogen production process at about 573K upstream from a turbine, it was found theoretically that the total energy utilization efficiency is about 50% and very high. By setting a turbine upstream of the hydrogen production plant, an overall efficiency of is 75% for an FBR and 76% for a supercritical-water cooled power reactor (SCPR). (author)

Why extraction lines and heaters in the turbine-condenser steam space should be lagged

Energy Technology Data Exchange (ETDEWEB)

Burns, J.M.; Haynes, C.J.

1998-07-01

Deregulated utilities face conditions today that necessitate their nuclear and fossil steam plants have the best possible heat rates. The low pressure turbine exhaust and condenser areas are known to be particularly sensitive to betterment. One relatively modest but cost effective heat rate improvement and one whose function and design is often misunderstood is the insulation of the extraction lines and heaters that are located within the turbine-condenser steam space. This paper discusses the dynamic environment of that turbine exhaust region and quantifies the application and benefit of stainless steel lagging to the extraction lines and heater shells within. The paper first focuses on the high energy, non-uniform steam flows of the turbine exhaust and how that impacts the heat losses, mechanical design and support of any components located inside that space. It then examines and quantifies the varieties of heat transfer from the heaters and extraction lines to the passing lower temperature, moist, high velocity turbine exhaust steam as it travels to the condenser. A new relationship is developed that defines the predominantly evaporative heat transfer mechanism on the exterior surfaces in contact with the exhaust steam. For a typical 630 MW fossil plant with three heater of different temperature levels in the steam space as exemplified by the US Generation fossil fired Brayton Point 3, the paper determined the additional condenser heat load and extra extraction steam. The paper lastly concluded that in this case, lagging the larger diameter lines of the lowest pressure heater and the heater itself is likely not cost-effective.

The fracture mechanics of steam turbine electron beam welded rotors

International Nuclear Information System (INIS)

Coulon, P.A.

1987-01-01

Increased steam turbine unit ratings presupposes that steelmakers are capable of manufacturing larger and larger rotor components. However, there are few steelmakers in the world capable of manufacturing monobloc rotors for high rated turbines, which limits the choice of supplier. Most nuclear turbine rotors have a composite arrangement and are made either by shrinking discs on a shaft or using elements welded together. Those in favour of welding have applied a classical socalled ''submerged'' method using a filler metal. However welding can also be performed by using an Electron Beam in a vacuum room without a filler metal. This technique has many advantages: mechanical characteristics of the joint are identical to those of the base material after tempering without heat affected zones. Moreover, parts are only very slightly deformed during welding. Two steam turbine rotors have been produced in this way. This paper described the destructive tests carried out in the four Electron Beam (EB) welds (two on each rotor)

Repair welding of cracked steam turbine blades

International Nuclear Information System (INIS)

Bhaduri, A.K.; Gill, T.P.S.; Albert, S.K.; Shanmugam, K.; Iyer, D.R.

1999-01-01

The procedure for repair welding of cracked steam turbine blades made of martensitic stainless steels has been developed using the gas tungsten arc welding process. Weld repair procedures were developed using both ER316L austenitic stainless steel filler wire and ER410 martensitic stainless steel filler wire. The repair welding procedure with austenitic filler wire was developed to avoid preheating of the blade as also hydrogen induced cold cracking, and involved evaluation of three different austenitic filler wires, viz. ER309L, ER316L and ERNiCr-3. The overall development of the repair welding procedure included selection of welding consumables (for austenitic filler metal), optimisation of post weld heat treatment parameters, selection of suitable method for local pre-heating and post-weld heat treatment (PWHT) of the blades, determination of mechanical properties of weldments in as-welded and PWHT conditions, and microstructural examination. After various trials using different procedures, the procedure of local PWHT using electrical resistance heating on the top surface of the weldment and monitoring the temperature by placing a thermocouple at the bottom of the weld, was found to give the most satisfactory results. A similar procedure was used for preheating while using ER410 filler metal. Mechanical testing of weldments before and after PWHT involved tensile tests at room temperature, face and root bend tests, and microhardness measurements across the fusion line and heat affected zone. During procedure qualification, mock-ups and actual repair welding, dye penetrant testing was used at different stages and where ever possible radiography was carried out. These procedures were developed for repair welding of cracked blades in the low-pressure (LP) steam turbines of Indian nuclear power plants. The procedure with ER316 L filler wire has so far been applied for repair welding of 2 cracked blades (made of AISI 410 SS) of LP steam turbines, while the procedure

Water feeding method upon reactor isolation

International Nuclear Information System (INIS)

Sasaki, Koichi; Takahara, Kuniaki; Hamamura, Kenji; Arakawa, Masahiro.

1990-01-01

The present invention concerns a method of feeding water upon reactor isolation in a plural loop type reactor having a plurality of reactor cooling systems. Water can be injected to a plurality of pools even if the pressure between the pools is not balanced and the water level in the reactor cooling system is optimally controlled. That is, water can be injected in accordance with the amount required for each of the pools by setting the opening of a turbine inlet steam control valve to somewhat higher than the cooling system pressure of the highest pressure loop. Water feeding devices upon reactor isolation were required by the same number as that for the reactor cooling systems. Whereas since pumps and turbines are used in common without worsening the water injection controllability to each of the loops according to the method of this invention and, accordingly, the cost performance can be improved. Further, since the opening degree of the turbine inlet steam control valve is controlled while making the difference pressure constant between the turbine inlet pressure and the pump exhaust pressure, the amount of the turbine exhausted steams can be reduced and, further, water injection controllability of the flow rate control valve in the injection line is improved. (I.S.)

Critical review of use of high pressure saturated steam turbine economizers in nuclear power plants

International Nuclear Information System (INIS)

Urbanek, J.

1981-01-01

In the high-pressure part of the turbine drops of moisture condensate, which causes erosion and has negative impact on the service-life of the turbine and on its thermodynamic efficiency. Various designs have been put forward to eliminate moisture. A good combination is moisture separation combined with the offtake of steam for the regeneration of feed water or for the steam re-heater. As concerns the high-pressure component of the turbine it is best to offtake steam for the feed water heater and for heating the steam between the high- and low-pressure components of the turbine. The connections of the heater and re-heater in diagrams of various manufacturers are evaluated and compared. It appears to be uneconomical to use the heater in cases where feed water would be heated to temperature considerably below its optimal value. (M.D.)

Analysis of experimental characteristics of multistage steam-jet electors of steam turbines

Science.gov (United States)

Aronson, K. E.; Ryabchikov, A. Yu.; Brodov, Yu. M.; Brezgin, D. V.; Zhelonkin, N. V.; Murmanskii, I. B.

2017-02-01

A series of questions for specification of physical gas dynamics model in flow range of steam-jet unit and ejector computation methodology, as well as functioning peculiarities of intercoolers, was formulated based on analysis of experimental characteristics of multistage team-jet steam turbines. It was established that coefficient defining position of critical cross-section of injected flow depends on characteristics of the "sound tube" zone. Speed of injected flow within this tube may exceed that of sound, and pressure jumps in work-steam decrease at the same time. Characteristics of the "sound tube" define optimal axial sizes of the ejector. According to measurement results, the part of steam condensing in the first-stage coolant constitutes 70-80% of steam amount supplied into coolant and is almost independent of air content in steam. Coolant efficiency depends on steam pressure defined by operation of steam-jet unit of ejector of the next stage after coolant of steam-jet stage, temperature, and condensing water flow. As a rule, steam entering content of steam-air mixture supplied to coolant is overheated with respect to saturation temperature of steam in the mixture. This should be taken into account during coolant computation. Long-term operation causes changes in roughness of walls of the ejector's mixing chamber. The influence of change of wall roughness on ejector characteristic is similar to the influence of reverse pressure of the steam-jet stage. Until some roughness value, injection coefficient of the ejector stage operating in superlimiting regime hardly changed. After reaching critical roughness, the ejector switches to prelimiting operating regime.

Monitoring of large steam turbines, as seen by the constructor and the operator

International Nuclear Information System (INIS)

Blanchet, J.M.; Bourcier, P.B.; Malherbe, C.

1986-01-01

The electricity in France is produced by large steam turbines in the range of 125 000 kW to 1 300 000 kW in nuclear power plants. Some operation problems are encountered on these large machines. The aim of this study is to justify and to describe the monitoring process implemented on the large steam turbines. This short study is divided into three parts: the monitoring justification during the start-up period, one example of a monitoring system, the turbine monitoring during the operation period [fr

Device for starting a steam generator by heating sodium in a reactor

International Nuclear Information System (INIS)

Nakano, Hisao.

1975-01-01

Object: To enhance cooperation between ventilation and steam conditions of turbine and ventilation condition relative to a superheater at the time of starting a plant using a fast breeder, and to enhance safety with respect to failure of heat transmission tubes at the time of start. Structure: In a device in which steam generated in an evaporator is fed to a high pressure turbine through a super-heater and an outlet steam of high pressure turbine is reheated by means of a re-heater and fed into a turbine on the side of low pressure to drive the turbine for power generation, opening and closing valves are mounted on outlet and inlet pipes, respectively, of the heat transmission pipe in the super heater, said outlet and inlet pipes being connected by a bypass pipe. Upstream side of the opening and closing valve on the inlet pipe and the downstream side of the opening and closing valve on the outlet pipe and connected by a bypass pipe in the re-heater and said bypass pipe in the re-heater is provided with a steam heat exchanger to be heated by steam in the outlet of the superheater, and a steam line in an auxiliary boiler is connected to the side of re-heater from the opening and closing valve on the heat transmission pipe in the re-heater. (Hanada, M.)

A review of helium gas turbine technology for high-temperature gas-cooled reactors

International Nuclear Information System (INIS)

No, Hee Cheon; Kim, Ji Hwan; Kim, Hyeun Min

2007-01-01

Current High-Temperature Gas-cooled Reactors (HTGRs) are based on a closed brayton cycle with helium gas as the working fluid. Thermodynamic performance of the axial-flow helium gas turbines is of critical concern as it considerably affects the overall cycle efficiency. Helium gas turbines pose some design challenges compared to steam or air turbomachinery because of the physical properties of helium and the uniqueness of the operating conditions at high pressure with low pressure ratio. This report present a review of the helium Brayton cycle experiences in Germany and in Japan. The design and availability of helium gas turbines for HTGR are also presented in this study. We have developed a new throughflow calculation code to calculate the design-point performance of helium gas turbines. Use of the method has been illustrated by applying it to the GTHTR300 reference

Remote inspection of steam turbine blades

International Nuclear Information System (INIS)

Anon.

1987-01-01

During the past five years Reinhart and Associates, Inc. has been involved in remote examination of L-0 and L-1 steam turbine blade rows of in-place LP turbines using visual and eddy current techniques. These tests have concentrated on the trailing edge and blade-to-rotor attachment (Christmas tree) areas. These remote nondestructive examinations were performed through hand access ports of the inner shell. Since the remote scanning system was in a prototype configuration, the inspection was highly operator-dependent. Refinement of the scanning equipment would considerably improve the efficiency of the test; however, the feasibility of remote in-place inspection of turbine blades was established. To further improve this technology, and to provide for remote inspection of other areas of the blade and additional turbine designs, EPRI is funding a one-year project with Reinhart and Associates, Inc. This project will develop a new system that employs state-of-the-art multifrequency eddy current techniques, a miniature charged coupled device (CCD) television camera, and remote positioning equipment. Project results from the first six months are presented

Material choices for the commercial fast reactor steam generators

International Nuclear Information System (INIS)

Willby, C.; Walters, J.

1978-01-01

Experience with fast reactor steam generators has shown them to be critical components in achieving a high availability. This paper presents the designers views on the use of ferritic materials for steam generators and describes the proposed design of the steam generators for the Commercial Fast Reactor (CFR), prototype of which are to be inserted in the Prototype Fast Reactor at Dounreay. (author)

Aerodynamic Optimization Design of a Multistage Centrifugal Steam Turbine and Its Off-Design Performance Analysis

Directory of Open Access Journals (Sweden)

Hui Li

2017-01-01

Full Text Available Centrifugal turbine which has less land occupation, simple structure, and high aerodynamic efficiency is suitable to be used as small to medium size steam turbines or waste heat recovery plant. In this paper, one-dimensional design of a multistage centrifugal steam turbine was performed by using in-house one-dimensional aerodynamic design program. In addition, three-dimensional numerical simulation was also performed in order to analyze design and off-design aerodynamic performance of the proposed centrifugal steam turbine. The results exhibit reasonable flow field and smooth streamline; the aerodynamic performance of the designed turbine meets our initial expectations. These results indicate that the one-dimensional aerodynamic design program is reliable and effective. The off-design aerodynamic performance of centrifugal steam turbine was analyzed, and the results show that the mass flow increases with the decrease of the pressure ratio at a constant speed, until the critical mass flow is reached. The efficiency curve with the pressure ratio has an optimum efficiency point. And the pressure ratio of the optimum efficiency agrees well with that of the one-dimensional design. The shaft power decreases as the pressure ratio increases at a constant speed. Overall, the centrifugal turbine has a wide range and good off-design aerodynamic performance.

Improvement of Steam Turbine Operational Performance and Reliability with using Modern Information Technologies

Science.gov (United States)

Brezgin, V. I.; Brodov, Yu M.; Kultishev, A. Yu

2017-11-01

The report presents improvement methods review in the fields of the steam turbine units design and operation based on modern information technologies application. In accordance with the life cycle methodology support, a conceptual model of the information support system during life cycle main stages (LC) of steam turbine unit is suggested. A classifying system, which ensures the creation of sustainable information links between the engineer team (manufacture’s plant) and customer organizations (power plants), is proposed. Within report, the principle of parameterization expansion beyond the geometric constructions at the design and improvement process of steam turbine unit equipment is proposed, studied and justified. The report presents the steam turbine unit equipment design methodology based on the brand new oil-cooler design system that have been developed and implemented by authors. This design system combines the construction subsystem, which is characterized by extensive usage of family tables and templates, and computation subsystem, which includes a methodology for the thermal-hydraulic zone-by-zone oil coolers design calculations. The report presents data about the developed software for operational monitoring, assessment of equipment parameters features as well as its implementation on five power plants.

Nuclear steam turbines for power production in combination with heating

International Nuclear Information System (INIS)

Frilund, B.; Knudsen, K.

1977-01-01

The general operating conditions for nuclear steam turbines in district heating system are briefly outlined. The turbine plant can consist of essentially the same types of machines as in conventional district heating systems. Some possible arrangements of back-pressure turbines, back-pressure turbines with condensing tails, or condensing turbines with heat extraction are considered for nuclear power and heat stations. Principles of control for hot water temperature and electrical output are described. Optimization of the plant, considering parallel variations during the year between heat load, cooling water temperature, and required outgoing temperature is discussed. (U.K.)

Enhanced efficiency steam turbine blading - for cleaner coal plant

Energy Technology Data Exchange (ETDEWEB)

Fowler, A.; Bell, D.; Cao, C.; Fowler, R.; Oliver, P.; Greenough, C.; Timmis, P. [ALSTOM Power, Rugby (United Kingdom)

2005-03-01

The aim of this project was to increase the efficiency of the short height stages typically found in high pressure steam turbine cylinders. For coal fired power plant, this will directly lead to a reduction in the amount of fuel required to produce electrical power, resulting in lower power station emissions. The continual drive towards higher cycle efficiencies demands increased inlet steam temperatures and pressures, which necessarily leads to shorter blade heights. Further advances in blading for short height stages are required in order to maximise the benefit. To achieve this, an optimisation of existing 3 dimensional designs was carried out and a new 3 dimensional fixed blade for use in the early stages of the high pressure turbine was developed. 28 figs., 5 tabs.

Development of High-Powered Steam Turbines by OAO NPO Central Research and Design Institute for Boilers and Turbines

Science.gov (United States)

Mikhailov, V. E.; Khomenok, L. A.; Kovalev, I. A.

2018-01-01

The article provides an overview of the developments by OAO NPO TsKTI aimed at improvement of components and assemblies of new-generation turbine plants for ultra-supercritical steam parameters to be installed at the power-generating facilities in service. The list of the assemblies under development includes cylinder shells, the cylinder's flow paths and rotors, seals, bearings, and rotor cooling systems. The authors consider variants of the shafting-cylinder configurations for which advanced high-pressure and intermediate-pressure cylinders with reactive blading and low-pressure cylinders of conventional design and with counter-current steam flows are proposed and high-pressure rotors, which can increase the economic efficiency and reduce the overall turbine plant dimensions. Materials intended for the equipment components that operate at high temperatures and a steam cooling technique that allows the use of cheaper steel grades owing to the reduction in the metal's working temperature are proposed. A new promising material for the bearing surfaces is described that enables the operation at higher unit pressures. The material was tested on a full-scale test bench at OAO NPO TsKTI and a turbine in operation. Ways of controlling the erosion of the blades in the moisture-steam turbine compartments by the steam heating of the hollow guide blades are considered. To ensure the dynamic stability of the shafting, shroud and diaphragm seals that prevent the development of the destabilizing circulatory forces of the steam flow were devised and trialed. Advanced instrumentation and software are proposed to monitor the condition of the blading and thermal stresses under transient conditions, to diagnose the vibration processes, and to archive the obtained data. Attention is paid to the normalization of the electromagnetic state of the plant in order to prevent the electrolytic erosion of the plant components. The instrumentation intended for monitoring the relevant electric

Biomass-gasifier steam-injected gas turbine cogeneration for the cane sugar industry

International Nuclear Information System (INIS)

Larson, E.D.; Williams, R.H.; Ogden, J.M.; Hylton, M.G.

1991-01-01

Steam injection for power and efficiency augmentation in aeroderivative gas turbines has been commercially established for natural gas-fired cogeneration since 1980. Steam-injected gas turbines fired with coal and biomass are being developed. A performance and economic assessment of biomass integrated-gasifier steam-injected gas turbine (BIG/STIG) cogeneration systems is carried out here. A detailed economic case study is presented for the second largest sugar factory in Jamaica, with cane residues as the fuel. BIG/STIG cogeneration units would be attractive investments for sugar producers, who could sell large quantities of excess electricity to the utility, or for the utility, as a low-cost generating option. Worldwide, the cane sugar industry could support some 50,000 MW of BIG/STIG electric generation capacity. The relatively modest development effort required to commercialize the BIG/STIG technology is discussed in a companion paper prepared for this conference

Thermal expansion measurement of turbine and main steam piping by using strain gages in power plants

International Nuclear Information System (INIS)

Na, Sang Soo; Chung, Jae Won; Bong, Suk Kun; Jun, Dong Ki; Kim, Yun Suk

2000-01-01

One of the domestic co-generation plants have undergone excessive vibration problems of turbine attributed to external force for years. The root cause of turbine vibration may be shaft alignment problem which sometimes is changed by thermal expansion and external force, even if turbine technicians perfectly performed it. To evaluate the alignment condition from plant start-up to full load, a strain measurement of turbine and main steam piping subjected to thermal loading is monitored by using strain gages. The strain gages are bonded on both bearing housing adjusting bolts and pipe stoppers which installed in the x-direction of left-side main steam piping near the turbine inlet in order to monitor closely the effect of turbine under thermal deformation of turbine casing and main steam piping during plant full load. Also in situ load of constant support hangers in main steam piping system is measured by strain gages and its results are used to rebalance the hanger rod load. Consequently, the experimental stress analysis by using strain gages turns out to be very useful tool to diagnose the trouble and failures of not only to stationary components but to rotating machinery in power plants

Modelling and simulation of the steam line, the high and low pressure turbines and the pressure regulator for the SUN-RAH nucleo electric university simulator

International Nuclear Information System (INIS)

Lopez R, A.

2003-01-01

In the following article the development of a simulator that allows to represent the dynamics of the following systems: steam line, nozzle, vapor separator, reheater, high pressure turbine, low pressure turbine, power generator and the pressure regulator of a nucleo electric power station. We start from the supposition that this plant will be modeled from a nuclear reactor type BWR (Boiling Water Reactor), using models of reduced order that represent the more important dynamic variables of the physical processes that happen along the steam line until the one generator. To be able to carry out the simulation in real time the Mat lab mathematical modeling software is used, as well as the specific simulation tool Simulink. It is necessary to point out that the platform on which the one is executed the simulator is the Windows operating system, to allow the intuitive use that only this operating system offers. The above-mentioned obeys to that the objective of the simulator it is to help the user to understand some of the dynamic phenomena that are present in the systems of a nuclear plant, and to provide a tool of analysis and measurement of variables to predict the desirable behavior of the same ones. The model of a pressure controller for the steam lines, the high pressure turbine and the low pressure turbine is also presented that it will be the one in charge of regulating the demand of the system according to the characteristics and critic restrictions of safety and control, assigned according to those wanted parameters of performance of this system inside the nucleo electric plant. This simulator is totally well defined and it is part of the University student nucleo electric simulator with Boiling Water Reactor (SUN-RAH), an integral project and of greater capacity. (Author)

Steam explosions in sodium cooled breeder reactors

International Nuclear Information System (INIS)

Lundell, B.

1982-01-01

Steam explosion is considered a physical process which transport heat from molten fuel to liquid coolant so fast that the coolant starts boiling in an explosion-like manner. The arising pressure waves transform part of the thermal energy to mechanical energy. This can stress the reactor tank and threaten its hightness. The course of the explosion has not been theoretical explained. Experimental results indicate that the probability of steam explosions in a breeder reactor is small. The efficiency of the transformation of the heat of fusion into mechanical energy in substantially lower than the theoretical maximum value. The mechanical stress from the steam explosion on the reactor tank does not seem to jeopardize its tightness. (G.B.)

Analysis of the Instability Phenomena Caused by Steam in High-Pressure Turbines

Directory of Open Access Journals (Sweden)

Paolo Pennacchi

2011-01-01

Full Text Available Instability phenomena in steam turbines may happen as a consequence of certain characteristics of the steam flow as well as of the mechanical and geometrical properties of the seals. This phenomenon can be modeled and the raise of the steam flow and pressure causes the increase of the cross coupled coefficients used to model the seal stiffness. As a consequence, the eigenvalues and eigenmodes of the mathematical model of the machine change. The real part of the eigenvalue associated with the first flexural normal mode of the turbine shaft may become positive causing the conditions for unstable vibrations. The original contribution of the paper is the application of a model-based analysis of the dynamic behavior of a large power unit, affected by steam-whirl instability phenomena. The model proposed by the authors allows studying successfully the experimental case. The threshold level of the steam flow that causes instability conditions is analyzed and used to define the stability margin of the power unit.

Boiler systems for nuclear powered reactors

International Nuclear Information System (INIS)

Cook, R.K.; George, B.V.

1979-01-01

A power generating plant which comprises a heat source, at least one main steam turbine and at least one main boiler heated by heat from the heat source and providing the steam to drive the turbine, comprises additionally at least one further steam turbine, smaller than the main turbine, and at least one further boiler, of lower capacity than the main boiler, and heated from the same heat source and providing steam for the further turbine. Particularly advantageous in nuclear power stations, where the heat source is a nuclear reactor, the invention enables peak loads, above the normal continuous rating of the main generators driven by the main turbines, to be met by the further turbine(s) and one or more further generators driven thereby. This enables the main turbines to be freed from the thermal stresses of rapid load changes, which stresses are more easily accommodated by the smaller and thus more tolerant further turbine(s). Thus auxiliary diesel-driven or other independent power plant may be made partly or wholly unnecessary. Further, low-load running which would be inefficient if achieved by means of the main turbine(s), can be more efficiently effected by shutting them down and using the smaller further turbine(s) instead. These latter may also be used to provide independent power for servicing the generating plant during normal operation or during emergency or other shutdown, and in this latter case may also serve as a heat sink for the shutdown reactor

Mechanical problems in turbomachines, steam and gas turbines. Large steam turbine manufacturing requirements to fulfill customer needs for electric power

International Nuclear Information System (INIS)

Brazzini, R.

1975-01-01

The needs of the customers in large steam turbines for electric power are examined. The choices and decisions made by the utility about the equipments are dealt with after considering the evolution of power demand on the French network. These decisions and choices mainly result from a technical and economic optimization of production equipments: choice of field-proven solutions, trend to lower steam characteristics, trend to higher output of the units (i.e. size effect), spreading out standardization of machines and components (policy of technical as well as technological levels, i.e. mass production effect). Standardization of external characteristics of units of same level of output and even standardization of some main components. The requirements turbine manufacturers have to meet may fall in two categories: on one side: gaining experience and know-how, capability of making high quality experiments, out put capacity, will to hold a high efficiency level; on the other side: meeting the technical requirements related to the contracts. Among these requirements, one can differentiate those dealing with the service expected from the turbine and that resulting in the responsibility limits of the manufacturer and those tending to gain interchangeability, to improve availability of the equipment, to increase safety, and to make operation and maintenance easier [fr

Application of new designed butterfly type intermediate valve for nuclear steam turbine

International Nuclear Information System (INIS)

Matsumura, Kazuhiro; Kawamata, Susumu; Fujita, Isao; Taketomo, Seiki.

1991-01-01

To cope with a large capacity nuclear steam turbine, a butterfly type intermediate valve has been developed. Compared to the conventional valve, or globe valve, the butterfly valve has the following design features: a) Higher thermal efficiency due to lower pressure loss, b) Easier maintenance due to simplified construction, and c) Lower station cost due to the smaller size of the valve assembly. An experiment with a scaled-down test valve was carried out using compressed air. Subsequently a full-scale valve was tested using steam under actual steam conditions. As a result, these tests gave us no problems. The first nuclear turbine (1100MW) equipped with a butterfly valve is operating satisfactorily with good performance as expected. (author)

Steam explosions in light water reactors

International Nuclear Information System (INIS)

1981-01-01

The report deals with a postulated accident caused by molten fuel falling into the lower plenum of the containment of a reactor. The analysis which is presented in the report shows that the thermal energy released in the resulting steam explosion is not enough to destroy the pressure vessel or the containment. The report was prepared for the Swedish Governmental Committee on steam explosion in light water reactors. It includes statements issued by internationally well-known specialists. (G.B.)

900 MW CP1 nuclear steam turbine retrofit thermal effects on low pressure diaphragms

International Nuclear Information System (INIS)

Buguin, A.; Gruau, P.; Lamarque, F.; Huggett, J.

2015-01-01

The steam turbines of the Koeberg units 1 and 2 operated by ESKOM in South Africa have been retrofitted in order to mitigate the generic problems of stress corrosion cracking of the original shrunk-on disk rotor design. As already done in Belgium and France, the implementation of welded rotors improves the turbine reliability and availability. Moreover, the new technology implemented associated with a new steam path allows a significant performance improvement. With a wealth of experience in CP1 retrofit, ALSTOM has put in place new technical features in the steam path in order to further improve the heat rate. Among them, steam balance holes drilled in the rotor disks have exacerbated the thermal sensitivity of the LP diaphragms. During the commissioning of the Unit 1 LP turbines following the retrofit, the load increase led to unacceptable vibrations. An investigation program was launched to determine the root causes of the problem. This paper presents the findings following the turbine inspection, as well as the recommendations and modifications to allow a smooth return to service of the unit. In addition, the results of the root cause analysis of the vibration incident are explained. Based on finite element calculations and site measurements, ALSTOM has established that the diaphragm thermal behavior, intensified by the steam balance holes, has led to radial rubbing. It was also established that the phenomena had no effect on the diaphragms mechanical integrity. Design changes have been proposed to ensure a safe and reliable long term operation of the units. These modifications have been successfully implemented onto the Koeberg Unit 2 Nuclear Steam Turbine commissioned in November 2012. (authors)

Reactor operation method

International Nuclear Information System (INIS)

Osumi, Katsumi; Miki, Minoru.

1979-01-01

Purpose: To prevent stress corrosion cracks by decreasing the dissolved oxygen and hydrogen peroxide concentrations in the coolants within a reactor container upon transient operation such as at the start-up or shutdown of bwr type reactors. Method: After a condensate has been evacuated, deaeration operation is conducted while opening a main steam drain line, as well as a main steam separation valve and a by-pass valve in a turbine by-pass line connecting the main steam line and the condenser without by way of a turbine, and the reactor is started-up by the extraction of control rods after the concentration of dissolved oxygen in the cooling water within a pressure vessel has been decreased below a predetermined value. Nuclear heating is started after the reactor water has been increased to about 150 0 C by pump heating after the end of the deaeration operation for preventing the concentration of hydrogen peroxide and oxygen in the reactor water from temporarily increasing immediately after the start-up. The corrosive atmosphere in the reactor vessel can thus be moderated. (Horiuchi, T.)

Aerodynamic Optimization Design of a Multistage Centrifugal Steam Turbine and Its Off-Design Performance Analysis

OpenAIRE

Hui Li; Dian-Gui Huang

2017-01-01

Centrifugal turbine which has less land occupation, simple structure, and high aerodynamic efficiency is suitable to be used as small to medium size steam turbines or waste heat recovery plant. In this paper, one-dimensional design of a multistage centrifugal steam turbine was performed by using in-house one-dimensional aerodynamic design program. In addition, three-dimensional numerical simulation was also performed in order to analyze design and off-design aerodynamic performance of the pro...

Graphite-water steam-generating reactor in the USSR

Energy Technology Data Exchange (ETDEWEB)

Dollezhal, N A [AN SSSR, Moscow

1981-10-01

One of the types of power reactor used in the USSR is the graphite-water steam-generating reactor RBMK. This produces saturated steam at a pressure of 7MPa. Reactors giving 1GWe each have been installed at the Leningrad, Kursk, Chernobyl and other power stations. Further stations using reactors of this type are being built. A description is given of the fuel element design, and of the layout of the plant. The main characteristics of RBMK reactors using fuel of rated and higher enrichment are listed.

A study on ex-vessel steam explosion for a flooded reactor cavity of reactor scale - 15216

International Nuclear Information System (INIS)

Song, S.; Yoon, E.; Kim, Y.; Cho, Y.

2015-01-01

A steam explosion can occur when a molten corium is mixed with a coolant, more volatile liquid. In severe accidents, corium can come into contact with coolant either when it flows to the bottom of the reactor vessel and encounters the reactor coolant, or when it breaches the reactor vessel and flows into the reactor containment. A steam explosion could then threaten the containment structures, such as the reactor vessel or the concrete walls/penetrations of the containment building. This study is to understand the shortcomings of the existing analysis code (TEXAS-V) and to estimate the steam explosion loads on reactor scale and assess the effect of variables, then we compared results and physical phenomena. Sensitivity study of major parameters for initial condition is performed. Variables related to melt corium such as corium temperature, falling velocity and diameter of melt are more important to the ex-vessel steam explosion load and the steam explosion loads are proportional to these variables related to melt corium. Coolant temperature on reactor cavity has a specific area to increase the steam explosion loads. These results will be used to evaluate the steam explosion loads using ROAAM (Risk Oriented Accident Analysis Methodology) and to develop the evaluation methodology of ex-vessel steam explosion. (authors)

Limit regulation system for pressurized water nuclear reactors

International Nuclear Information System (INIS)

Aleite, W.; Bock, H.W.

1976-01-01

Described is a limit regulation system for a pressurized water nuclear reactor in combination with a steam generating system connected to a turbine, the nuclear reactor having control rods as well as an operational regulation system and a protective system, which includes reactor power limiting means operatively associated with the control rods for positioning the same and having response values between operating ranges of the operational regulation system, on the one hand, and response values of the protective system, on the other hand, and a live steam-minimal pressure regulation system cooperating with the reactor power limiting means and operatively connected to a steam inlet valve to the turbine for controlling the same

Risk-based and maintenance systems for steam turbines

International Nuclear Information System (INIS)

Fujiyama, K.; Nagai, S.; Akikuni, Y.; Fujiwara, T.; Furuya, K.; Matsumoto, S.; Takagi, K.; Kawabata, T.

2003-01-01

The risk-based maintenance (RBM) system has been developed for steam turbine plants coupled with the quick inspection systems. The RBM system utilizes the field failure and inspection database accumulated over 30 years. The failure modes are determined for each component of steam turbines and the failure scenarios are described as event trees. The probability of failure is expressed in the form of unreliability functions of operation hours or start-up cycles through the cumulative hazard function method. The posterior unreliability is derived from the field data analysis according to the inspection information. Quick inspection can be conducted using air-cooled borescope and heat resistant ultrasonic sensors even if the turbine is not cooled down sufficiently. Another inspection information comes from degradation and damage measurement. The probabilistic life assessment using structural analysis and statistical material properties, the latter is estimated from hardness measurement, replica observation and embrittlement measurement. The risk function is calculated as the sum product of unreliability functions and expected monetary loss as the consequence of failure along event trees. The optimum maintenance plan is determined among simulated scenarios described through component breakdown trees, life cycle event trees and risk functions. Those methods are effective for total condition assessment and economical maintenance for operating plants. (orig.)

Design of large reheat steam turbines for U.K. and overseas markets

International Nuclear Information System (INIS)

Mitchell, J.M.

1979-01-01

Two prototype designs of large reheat steam turbines are described, together with the technical, economic and plant design aspects that have influenced their main features. Relevant service experience is outlined and details are given of the solutions adopted to overcome the relatively few problems that were encountered. The evolution of these designs to form the current range of adaptable, pre-engineered modular designs is presented and the main features of current machines are described. A brief account is given of likely future developments in large steam turbines. (author)

Optimized Application of MSR and Steam Turbine Retrofits in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Crossland, Robert; McCoach, John [ALSTOM Power, Willans Works, Newbold Road, Rugby, Warwickshire CV21 2NH (United Kingdom); Gagelin, Jean-Philippe [ALSTOM Power Heat Exchange, 19-21 avenue Morane-Saulnier, BP 65, 78143 Velizy Cedex (France)

2004-07-01

The benefit to a nuclear power plant from a steam turbine retrofit has often been clearly demonstrated in recent years but, for light water nuclear plants, the Moisture Separator Reheaters (MSRs) are also of prime importance. This paper describes how refurbishment of these crucial components can only provide full potential performance benefit when made in conjunction with a steam turbine retrofit (although in practice these activities are frequently separated). Examples are given to show how combined application is best handled within a single organization to ensure optimized integration into the thermal cycle. (authors)

Optimized Application of MSR and Steam Turbine Retrofits in Nuclear Power Plants

International Nuclear Information System (INIS)

Crossland, Robert; McCoach, John; Gagelin, Jean-Philippe

2004-01-01

The benefit to a nuclear power plant from a steam turbine retrofit has often been clearly demonstrated in recent years but, for light water nuclear plants, the Moisture Separator Reheaters (MSRs) are also of prime importance. This paper describes how refurbishment of these crucial components can only provide full potential performance benefit when made in conjunction with a steam turbine retrofit (although in practice these activities are frequently separated). Examples are given to show how combined application is best handled within a single organization to ensure optimized integration into the thermal cycle. (authors)

Upgrading the SPP-500-1 moisture separators-steam reheaters used in the Leningrad NPP turbine units

Science.gov (United States)

Legkostupova, V. V.; Sudakov, A. V.

2015-03-01

The specific features of existing designs of moisture separators-steam reheaters (MSRs) and experience gained with using them at nuclear power plants are considered. Main factors causing damage to and failures of MSRs are described: nonuniform distribution of wet steam flow among the separation modules, breakthrough of moisture through the separator (and sometimes also through the steam reheater), which may lead to the occurrence of additional thermal stresses and, hence, to thermal-fatigue damage to or stress corrosion cracking of metal. MSR failure results in a less efficient operation of the turbine unit as a whole and have an adverse effect on the reliability of the low-pressure cylinder's last-stage blades. By the time the design service life of the SPP-500-1 MSRs had been exhausted in power units equipped with RBMK-1000 reactors, the number of damages inflicted to both the separation part and to the pipework and heating surface tubes was so large, that a considerable drop of MSR effectiveness and turbine unit efficiency as a whole occurred. The design of the upgraded separation part used in the SPP-500-1 MSR at the Leningrad NPP is described and its effectiveness is shown, which was confirmed by tests. First, efforts taken to achieve more uniform distribution of moisture content over the perimeter and height of steam space downstream of the separation modules and to bring it to values close to the design ones were met with success. Second, no noticeable effect of the individual specific features of separation modules on the moisture content was revealed. Recommendations on elaborating advanced designs of moisture separators-steam reheaters are given: an MSR arrangement in which the separator is placed under or on the side from the steam reheater; axial admission of wet steam for ensuring its uniform distribution among the separation modules; inlet chambers with an extended preliminary separation system and devices for uniformly distributing steam flows in the

Using the artificial neural network to control the steam turbine heating process

International Nuclear Information System (INIS)

Nowak, Grzegorz; Rusin, Andrzej

2016-01-01

Highlights: • Inverse Artificial Neural Network has a potential to control the start-up process of a steam turbine. • Two serial neural networks made it possible to model the rotor stress based of steam parameters. • An ANN with feedback enables transient stress modelling with good accuracy. - Abstract: Due to the significant share of renewable energy sources (RES) – wind farms in particular – in the power sector of many countries, power generation systems become sensitive to variable weather conditions. Under unfavourable changes in weather, ensuring required energy supplies involves hasty start-ups of conventional steam power units whose operation should be characterized by higher and higher flexibility. Controlling the process of power engineering machinery operation requires fast predictive models that will make it possible to analyse many parallel scenarios and select the most favourable one. This approach is employed by the algorithm for the inverse neural network control presented in this paper. Based on the current thermal state of the turbine casing, the algorithm controls the steam temperature at the turbine inlet to keep both the start-up rate and the safety of the machine at the allowable level. The method used herein is based on two artificial neural networks (ANN) working in series.

Laser shock peening of steam turbine blade for enhanced service life

Indian Academy of Sciences (India)

2014-02-13

Feb 13, 2014 ... Fretting-fatigue is an important factor influencing service life of turbine blades. The present paper describes laser shock peening of potential crack nucleation site in the root region of steam turbine blade for its enhanced service life. The experimental study, performed with an in-house developed 2.5 J/7 ns ...

Thermoeconomic Modeling and Parametric Study of Hybrid Solid Oxide Fuel Cell â Gas Turbine â Steam Turbine Power Plants Ranging from 1.5 MWe to 10 MWe

OpenAIRE

Arsalis, Alexandros

2007-01-01

Detailed thermodynamic, kinetic, geometric, and cost models are developed, implemented, and validated for the synthesis/design and operational analysis of hybrid solid oxide fuel cell (SOFC) â gas turbine (GT) â steam turbine (ST) systems ranging in size from 1.5 MWe to 10 MWe. The fuel cell model used in this thesis is based on a tubular Siemens-Westinghouse-type SOFC, which is integrated with a gas turbine and a heat recovery steam generator (HRSG) integrated in turn with a steam turbi...

Turbine flow diagram of Paks-1 reactor

International Nuclear Information System (INIS)

Vancso, Tamas

1983-01-01

Computer calculations and programs are presented which inform the operators on the effect projected on the turbine and thermal efficiency of the modification in the flow diagram and in the starting parameters of the power cycle. In the program the expansion line of steam turbine type K-220-44 and the thermo-technical parameters of the elements of the feed-water heater system are determined. Detailed degree calculations for turbine unit of high pressure can be made. (author)

The 52-inch last-stage blades for steam turbines

International Nuclear Information System (INIS)

Suzuki, Atsuhide; Hisa, Shoichi; Nagao, Shin-ichiro; Ogata, Hisao

1986-01-01

The last-stage blades (LSB) of steam turbines are one of the most important components determining the plant's maximum capacity and efficiency. The development of LSBs necessitates high-technology including advanced methods of analyses and verifications as well as ample accumulation of technical data. The 52-inch LSB recently developed by Toshiba has raised nuclear power plant's capacity up to 1,300 ∼ 1,800 MW, has effected compact design of turbine units, and has improved thermal efficiency, keeping high reliability. (author)

A process for superheating steam in a nuclear power station circuit and device for putting in operation this process

International Nuclear Information System (INIS)

Monteil, Marcel; Forestier, Jean; Leblanc, Bernard; Monteil, Pierre

1975-01-01

A process is described for superheating steam in a nuclear power station circuit, comprising a turbine with a high pressure chamber and a low pressure chamber. It consists in superheating the steam between the high and low pressure chambers of the turbine by using as heating fluid water under pressure at vaporisation temperature, directly taken from the recirculation or circulation flow water of the reactor or of the steam generators. The process is adapted to a pressurised water reactor using a once-through steam generator comprising in succession an economiser, a vaporiser and a superheater, the superheating water being taken at the vaporiser intake. It is also adapted for a boiling water reactor, in that the water is taken directly from the reactor vessel and at a suitable level in the recirculation water [fr

Energy and exergy analysis of the turbo-generators and steam turbine for the main feed water pump drive on LNG carrier

International Nuclear Information System (INIS)

Mrzljak, Vedran; Poljak, Igor; Mrakovčić, Tomislav

2017-01-01

Highlights: • Two low-power steam turbines in the LNG carrier propulsion plant were investigated. • Energy and exergy efficiencies of both steam turbines vary between 46% and 62%. • The ambient temperature has a low impact on exergy efficiency of analyzed turbines. • The maximum efficiencies area of both turbines was investigated. • A method for increasing the turbo-generator efficiencies by 1–3% is presented. - Abstract: Nowadays, marine propulsion systems are mainly based on internal combustion diesel engines. Despite this fact, a number of LNG carriers have steam propulsion plants. In such plants, steam turbines are used not only for ship propulsion, but also for electrical power generation and main feed water pump drive. Marine turbo-generators and steam turbine for the main feed water pump drive were investigated on the analyzed LNG carrier with steam propulsion plant. The measurements of various operating parameters were performed and obtained data were used for energy and exergy analysis. All the measurements and calculations were performed during the ship acceleration. The analysis shows that the energy and exergy efficiencies of both analyzed low-power turbines vary between 46% and 62% what is significantly lower in comparison with the high-power steam turbines. The ambient temperature has a low impact on exergy efficiency of analyzed turbines (change in ambient temperature for 10 °C causes less than 1% change in exergy efficiency). The highest exergy efficiencies were achieved at the lowest observed ambient temperature. Also, the highest efficiencies were achieved at 71.5% of maximum developed turbo-generator power while the highest efficiencies of steam turbine for the main feed water pump drive were achieved at maximum turbine developed power. Replacing the existing steam turbine for the main feed water pump drive with an electric motor would increase the turbo-generator energy and exergy efficiencies for at least 1–3% in all analyzed

Issues to improve the safety of 18K370 steam turbine operation

Directory of Open Access Journals (Sweden)

Bzymek Grzegorz

2017-01-01

Full Text Available The paper presents the process of improving the safety and reliability of operation the 18K370 steam turbines Opole Power Plant since the first failure in 2010 [1], up to install the on-line monitoring system [2]. It shows how the units work and how to analyse the contol stage as a critical node in designing the turbine. Selected results of the analysis of the strength of CSD (Computational Solid Dynamic and the nature of the flow in different operating regimes - thanks to CFD (Computational Fluid Dynamic analysis have been included. We have also briefly discussed the way of lifecycle management of individual elements [2,3]. The presented actions could be considered satisfactory, and improve the safety of operating steam turbines of type 18K370.

Cooling of nuclear power stations with high temperature reactors and helium turbine cycles

International Nuclear Information System (INIS)

Foerster, S.; Hewing, G.

1977-01-01

On nuclear power stations with high temperature reactors and helium turbine cycles (HTR-single circuits) the residual heat from the energy conversion process in the primary and intermediate coolers is removed from cycled gas, helium. Water, which is circulated for safety reasons through a closed circuit, is used for cooling. The primary and intermediate coolers as well as other cooling equipment of the power plant are installed within the reactor building. The heat from the helium turbine cycle is removed to the environment most effectively by natural draught cooling towers. In this way a net plant efficiency of about 40% is attainable. The low quantities of residual heat thereby produced and the high (in comparison with power stations with steam turbine cycles) cooling agent pressure and cooling water reheat pressure in the circulating coolers enable an economically favourable design of the overall 'cold end' to be expected. In the so-called unit range it is possible to make do with one or two cooling towers. Known techniques and existing operating experience can be used for these dry cooling towers. After-heat removal reactor shutdown is effected by a separate, redundant cooling system with forced air dry coolers. The heat from the cooling process at such locations in the power station is removed to the environment either by a forced air dry cooling installation or by a wet cooling system. (orig.) [de

Analysis of Turbine Load Rejection for APR1400 using SPACE

Energy Technology Data Exchange (ETDEWEB)

Kim, Sang Jin; Park, Chan Eok; Choi, Jong Ho; Lee, Gyu Cheon [KEPCO Engineering and Construction Co. Ltd., Deajeon (Korea, Republic of)

2016-10-15

Turbine Load Rejection event is one of the Performance Related Design Basis Event (PRDBE) that can be stabilized using plant control systems without any safety system actuation. The initiation of the event is turbine load rejection from 100% to 5% in 0.019 seconds. The NSSS control systems of APR1400 is composed of the Power Control System (PCS) and the Process-Component Control System (P-CCS). The PCS includes Reactor Regulating System (RRS), Reactor Power Cutback System (RPCS) and Digital Rod Control System (DRCS). The P-CCS includes the Pressurizer Pressure Control System (PPCS), the Pressurizer Level Control System (PLCS), the Feedwater Control System (FWCS) and the Steam Bypass Control System (SBCS). Turbine load rejection results in the increase of secondary pressure due to sudden blocking of steam flow to turbine. Then the Reactor Coolant System (RCS) cooling through steam generators is decreased rapidly and the RCS temperature will be increased. Turbine load rejection is a typical event to test NSSS control systems since it requires the automatic response of all major NSSS control systems. It is shown that the NSSS control systems of APR1400 have the capability to stabilize the plant without any safety system actuation for turbine load rejection event. This analysis results show that SPACE code has the capability to analyze the turbine load rejection event. However, further validation is necessary for other PRDBEs such as Two Main Feedwater Pumps Trip, Turbine Load Step Change and Turbine Load Ramp Down (5%/min) to verify the capability of SPACE for the full range of performance analyses.

Analysis of Turbine Load Rejection for APR1400 using SPACE

International Nuclear Information System (INIS)

Kim, Sang Jin; Park, Chan Eok; Choi, Jong Ho; Lee, Gyu Cheon

2016-01-01

Turbine Load Rejection event is one of the Performance Related Design Basis Event (PRDBE) that can be stabilized using plant control systems without any safety system actuation. The initiation of the event is turbine load rejection from 100% to 5% in 0.019 seconds. The NSSS control systems of APR1400 is composed of the Power Control System (PCS) and the Process-Component Control System (P-CCS). The PCS includes Reactor Regulating System (RRS), Reactor Power Cutback System (RPCS) and Digital Rod Control System (DRCS). The P-CCS includes the Pressurizer Pressure Control System (PPCS), the Pressurizer Level Control System (PLCS), the Feedwater Control System (FWCS) and the Steam Bypass Control System (SBCS). Turbine load rejection results in the increase of secondary pressure due to sudden blocking of steam flow to turbine. Then the Reactor Coolant System (RCS) cooling through steam generators is decreased rapidly and the RCS temperature will be increased. Turbine load rejection is a typical event to test NSSS control systems since it requires the automatic response of all major NSSS control systems. It is shown that the NSSS control systems of APR1400 have the capability to stabilize the plant without any safety system actuation for turbine load rejection event. This analysis results show that SPACE code has the capability to analyze the turbine load rejection event. However, further validation is necessary for other PRDBEs such as Two Main Feedwater Pumps Trip, Turbine Load Step Change and Turbine Load Ramp Down (5%/min) to verify the capability of SPACE for the full range of performance analyses

Superheated steam annealing of pressurized water reactor vessel

International Nuclear Information System (INIS)

Porowski, J.S.

1993-01-01

Thermal annealing of an embrittled Reactor Pressure Shell is the only recognized means for recovering material properties lost due to long-term exposure of the reactor walls to radiation. Reduced toughness of the material during operation is a major concern in evaluations of structural integrity of older reactors. Extensive studies performed within programs related to life extension of nuclear plants have confirmed that the thermal treatment of 850 deg. F for 168 hours on irradiated material essentially recovers material properties lost due to neutron exposure. Dry and wet annealing methods have been considered. Wet annealing involves operating the reactor at near design temperatures and pressures. Since the temperature of wet annealing must be limited to vessel design temperature of 650 deg. F, only partial recovery of the lost properties is achieved. Thus dry annealing was selected as an alternative for future development and industrial implementation to extend the safe life of reactors. Dry thermal annealing consists of heating portions of the reactor vessel at a specific temperature for a given period of time using a high temperature heat source. The use of spent fuel assemblies, induction heating and resistance heating elements as well as the circulation of heated fluid were investigated as potential candidate methods. To date the use of resistance heating elements which are lowered into a dry empty reactor was considered to be the preferred method. In-depth research in the United States and practical applications of such a method in Russia have confirmed feasibility of the method. The method of using circulating superheated steam to anneal the vessel at 850 deg. F without complete removal of the reactor internals is described herein. After removing the reactor head and fuel, the core barrel along with the upper and lower core in PWRs is lifted to open an annular space between the reactor shell flange and the core barrel flange. The thermal shield can remain

Application of Computer Simulation to Identify Erosion Resistance of Materials of Wet-steam Turbine Blades

Science.gov (United States)

Korostelyov, D. A.; Dergachyov, K. V.

2017-10-01

A problem of identifying the efficiency of using materials, coatings, linings and solderings of wet-steam turbine rotor blades by means of computer simulation is considered. Numerical experiments to define erosion resistance of materials of wet-steam turbine blades are described. Kinetic curves for erosion area and weight of the worn rotor blade material of turbines K-300-240 LMP and atomic icebreaker “Lenin” have been defined. The conclusion about the effectiveness of using different erosion-resistant materials and protection configuration of rotor blades is also made.

Performance analysis of a small regenerative gas turbine system adopting steam injection and side-wall in finned tube evaporator

International Nuclear Information System (INIS)

Kang, Soo Young; Lee, Jong Jun; Kim, Tong Seop

2009-01-01

Small gas turbines in power range of several MWs are quite suitable for application in distributed generation as well as Community Energy Systems (CES). Humidification is an effective way to improve gas turbine performance, and steam injection is the most general and practically feasible method. This study intended to examine the effect of steam injection on the performance of several MW class gas turbines. A primary concern is given to the regenerative cycle gas turbine. The steam injection effect on the performance of a system without the regenerator (i.e. a simple cycle) is also examined. In addition, the influence of bypass of some of the exhaust gas on the performance of the gas turbine, especially the regenerative cycle gas turbine, is evaluated.

Power Plants, Steam and Gas Turbines WebQuest

Science.gov (United States)

Ulloa, Carlos; Rey, Guillermo D.; Sánchez, Ángel; Cancela, Ángeles

2012-01-01

A WebQuest is an Internet-based and inquiry-oriented learning activity. The aim of this work is to outline the creation of a WebQuest entitled "Power Generation Plants: Steam and Gas Turbines." This is one of the topics covered in the course "Thermodynamics and Heat Transfer," which is offered in the second year of Mechanical…

Station power supply by residual steam of Fugen

Energy Technology Data Exchange (ETDEWEB)

Kamiya, Y.; Kato, H.; Hattori, S. (Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan))

1981-09-01

In the advanced thermal reactor ''Fugen'', when the sudden decrease of load more than 40% occurs due to the failure of power system, the turbine regulating valve is rapidly shut, and the reactor is brought to scrum. However, the operation of turbo-generators is continued with the residual steam in the reactor, and the power for inside the station is supplied for 30 sec by the limiting timer, then the power-generating plant is automatically stopped. The reasons why such design was adopted are to reduce manual operation at the time of emergency, to continue water supply for cooling the reactor and to maintain the water level in the steam drum, and to reduce steam release from the safety valve and the turbine bypass valve. The output-load unbalance relay prevents the everspeed of the turbo-generator when load decreased suddenly, but when the failure of power system is such that recovers automatically in course of time, it does not work. The calculation for estimating the dynamic characteristics at the time of the sole operation within the station is carried out by the analysis code FATRAC. The input conditions for the calculation and the results are reported. Also the dynamic characteristics were actually tested to confirm the set value of the limiting timer and the safe working of turbine and generator trips. The estimated and tested results were almost in agreement.

The development of control systems for high power steam turbines

International Nuclear Information System (INIS)

Mathey, M.

1983-01-01

The functional and technological aspects of developments in the field of control systems for steam turbines over the last twenty years are analyzed. These developments have now culminated in very sophisticated systems which closely link electronics to high pressure hydraulic technology. A detailed description of these systeme high-lighting the high technical level of the control methods and the flexibility and reliability in service of turbines controlled in this way is given [fr

Steam Turbine Materials for Ultrasupercritical Coal Power Plants

Energy Technology Data Exchange (ETDEWEB)

Viswanathan, R.; Hawk, J.; Schwant, R.; Saha, D.; Totemeier, T.; Goodstine, S.; McNally, M.; Allen, D. B.; Purgert, Robert

2009-06-30

The Ultrasupercritical (USC) Steam Turbine Materials Development Program is sponsored and funded by the U.S. Department of Energy and the Ohio Coal Development Office, through grants to Energy Industries of Ohio (EIO), a non-profit organization contracted to manage and direct the project. The program is co-funded by the General Electric Company, Alstom Power, Siemens Power Generation (formerly Siemens Westinghouse), and the Electric Power Research Institute, each organization having subcontracted with EIO and contributing teams of personnel to perform the requisite research. The program is focused on identifying, evaluating, and qualifying advanced alloys for utilization in coal-fired power plants that need to withstand steam turbine operating conditions up to 760°C (1400°F) and 35 MPa (5000 psi). For these conditions, components exposed to the highest temperatures and stresses will need to be constructed from nickel-based alloys with higher elevated temperature strength than the highchromium ferritic steels currently used in today's high-temperature steam turbines. In addition to the strength requirements, these alloys must also be weldable and resistant to environmental effects such as steam oxidation and solid particle erosion. In the present project, candidate materials with the required creep strength at desired temperatures have been identified. Coatings that can resist oxidation and solid particle erosion have also been identified. The ability to perform dissimilar welds between nickel base alloys and ferritic steels have been demonstrated, and the properties of the welds have been evaluated. Results of this three-year study that was completed in 2009 are described in this final report. Additional work is being planned and will commence in 2009. The specific objectives of the future studies will include conducting more detailed evaluations of the weld-ability, mechanical properties and repair-ability of the selected candidate alloys for rotors

Utilization of multi-purpose high temperature gas-cooled reactors

International Nuclear Information System (INIS)

Kawada, Osamu; Onuki, Yoshiaki; Wasaoka, Takeshi.

1974-01-01

Concerning the utilization of multi-purpose high temperature gas-cooled reactors, the electric power generation with gas turbines is described: features of HTR-He gas turbine power plants; the state of development of He gas turbines; and combined cycle with gas turbines and steam turbines. The features of gas turbines concern heat dissipation into the environment and the mode of load operation. Outstanding work in the development of He gas turbines is that in Hochtemperatur Helium-Turbine Project in West Germany. The power generation with combined gas turbines and steam turbines appears to be superior to that with gas turbines alone. (Mori, K.)

Power plant and system for accelerating a cross compound turbine in such plant, especially one having an HTGR steam supply

International Nuclear Information System (INIS)

Jaegtnes, K.O.; Braytenbah, A.S.

1979-01-01

In accordance with the present invention, a power plant includes a steam source to generate superheat and reheat steam which flows through a turbine-generator and an associated bypass system. A high-pressure and an intermediate-pressure turbine portion drive a first electrical generating means, and a low-pressure turbine portion drives a second electrical generating means. A first flow of superheat steam flows through the high-pressure portion, while a second flow of reheat steam flows through the intermediate and low-pressure portions in succession. Provision is made for bypassing steam around the turbine portions; in particular, one bypass means permits a flow of superheat steam from the steam source to the exhaust of the high-pressure portion, and another bypass means allows reheated steam to pass from the source to the exhaust of the low-pressure portion. The first and second steam flows are governed independently. While one of such flows is varied for purposes of controlling the rotational speed of the first generating means according to a desired speed, the other flow is varied to regulate a power plant variable at its desired level. (author)

DESAIN AWAL TURBIN UAP TIPE AKSIAL UNTUK KONSEP RGTT30 BERPENDINGIN HELIUM

Directory of Open Access Journals (Sweden)

Sri Sudadiyo

2016-06-01

FOR HELIUM-COOLED RGTT30 CONCEPT. The concept of a nuclear power reactor, which evolves, is high temperature gas-cooled reactor type (HTGR. Gas that is used to cool the HTGR core, is helium. The HTGR concept used in this study can yield thermal power of 30 MWth so that named RGTT30. Helium temperature can reach 700 °C when come out from the RGTT30 core and it is used for heating the water within steam generator to achieve the temperature of 435 °C. The steam generator is connected to a steam turbine, which is coupled with an electricity generator, for generating electric power of 7.27 MWe. The steam that comes out from the turbine is flowed through condenser for changing the steam into water. The component train of steam generator, turbine, and condenser was given the name of steam turbine system. The turbine consists of blades that are intended to transform the steam power into mechanical power in the form of rotational speed. Turbine efficiency is a parameter that must be considered in this steam turbine system. The aims of this paper are to propose blade of axial type and to analyze the efficiency improvement of the turbine. The method used is the application of the thermodynamic principles associated with conservations of energy and mass. Cycle-Tempo software is used to obtain thermodynamic parameters and to simulate the steam turbine system based on RGTT30. Firstly, a scenario is created to model and simulate the steam turbine system for determining the efficiency and the mass flow rate of steam. The optimal values for the efficiency and the mass flow rates at the speed of 3000 rpm are 87.52 % and 8.759 kg/s, respectively. Then, the steam turbine was given the blade of axial type with a tip diameter of 1580 mm and a length of 150 mm. The results obtained are turbine efficiency increasing to 88.3% on constant speed (3000 rpm. Enhancement in the turbine efficiency value of 0.78% showed raising the overall performance of RGTT30. Keywords: Axial type, steam turbine

Risk-based inspection and maintenance systems for steam turbines

International Nuclear Information System (INIS)

Fujiyama, Kazunari; Nagai, Satoshi; Akikuni, Yasunari; Fujiwara, Toshihiro; Furuya, Kenichiro; Matsumoto, Shigeru; Takagi, Kentaro; Kawabata, Taro

2004-01-01

The risk-based maintenance (RBM) system has been developed for steam turbine plants coupled with the quick inspection systems. The RBM system utilizes the field failure and inspection database accumulated over 30 years. The failure modes are determined for each component of steam turbines and the failure scenarios are described as event trees. The probability of failure is expressed in the form of unreliability functions of operation hours or start-up cycles through the cumulative hazard function method. The posterior unreliability is derived from the field data analysis according to the inspection information. Quick inspection can be conducted using air-cooled borescope and heat resistant ultrasonic sensors even if the turbine is not cooled down sufficiently. Another inspection information comes from degradation and damage measurement. The probabilistic life assessment using structural analysis and statistical material properties, the latter is estimated from hardness measurement, replica observation and embrittlement measurement. The risk function is calculated as the sum product of unreliability functions and expected monetary loss as the consequence of failure along event trees. The optimum maintenance plan is determined among simulated scenarios described through component breakdown trees, life cycle event trees and risk functions. Those methods are effective for total condition assessment and economical maintenance for operating plants

Application of the Combined Cycle LWR-Gas Turbine to PWR for NPP Life Extension Safety Upgrade and Improving Economy

International Nuclear Information System (INIS)

Kuznetsov, Yu. N.

2006-01-01

Currently, some of the most important problem for the nuclear industry are life extension, advance competitiveness and safety of aging LWR NPPs. Based on results of studies performed in the USA (Battelle Memorial Institute) and in Russia (NIKIET), a new power technology, using a combined cycle gas-turbine facility CCGT - LWR, so called TD-Cycle, can significantly help in resolution of some problems of nuclear power industry. The nuclear steam and gas topping cycle is used for re-powering a light water pressurized reactor of PWR or VVER type. An existing NPP is topped with a gas turbine facility with a heat recovery steam generator (HRSG) generating steam from waste heat. The superheated steam of high pressure (P=90-165 bar, T=500-550 C) generated in the HRSG, is expanded in a high pressure (HP) turbine for producing electricity. The HP turbine can work on one shaft with the the gas turbine or at one shaft with intermediate (IP) or low (LP) pressure parts of the main nuclear steam turbine, or with a separate electric generator. The exhausted steam from the HP turbine is injected into the steam mixer where it is mixed with the saturated steam from the NPP steam generator (SG). The mixer is intended to superheat the main nuclear steam and should be characterized by minimum losses during mixing superheated and saturated steam. Steam from the mixer superheated by 20-60 C directs to the existing IP turbine, and then, through a separator-reheater flows into the LP turbine. Feed water re-heaters of LP and HP are actually unchanged in this case. Feed water extraction to the HRSG is supplied after one of LP water heaters. This proposal is intended to re-power existing LWR NPPs. To minimize cost, the IP and LP turbines and electric generator would remain the same. The reactor thermal power and fast neutron flux to the reactor vessel would decrease by 30-50 percent of nominal values. The external peripheral row of fuel elements can be replaced with metal absorber rods to

Estimation of Temperature Influence on Creep Rate of High-Temperature Elements in Steam Turbines and Steam Pipelines

Directory of Open Access Journals (Sweden)

A. G. Gerasimova

2011-01-01

Full Text Available The paper considers a high temperature influence on strength characteristics of steam pipelines and steam turbine parts of high and medium pressure. The charts showing a decisive temperature importance in diffuse creep have been presented in the paper. The paper contains a calculation of steel self-diffusion coefficient. Dependence Dsd = f(t for more accurate assessment of  resource characteristics of the applied steel has been proposed in the paper.

Gas-steam turbine plant for cogenerative process at 'Toplifikacija' - Skopje (Joint-Stock Co. for district heating - Macedonia)

International Nuclear Information System (INIS)

Cvetkovski, Andrijan

2003-01-01

The gas-steam power plant for combined heat and electric power production at A.D. 'Toplifikacija' Skopje - TO 'Zapad' is analyzed and determined. The analyzed plant is consisted of gas turbine, heat recovery steam generator (HRSG) and condensate steam turbine with controlled steam extraction. It operates on natural gas as a main fuel source. The heating of the water for the district heating is dine in the heat exchanger, with // heat of controlled extraction from condensate turbine. The advantages of the both binary plant and centralized co generative production compared with the individual are analyzed. The natural gas consumption of for both specific heating and electrical capacity in join production as well as fuel savings compared to the separate production of the same quantity of energy is also analyzed. (Original)

Through-flow analysis of steam turbines operating under partial admission

International Nuclear Information System (INIS)

Delabriere, H.; Werthe, J.M.

1993-05-01

In order to produce electric energy with improved efficiency, Electricite de France has to check the performances of equipment proposed by manufacturers. In the specific field of steam turbines, one of the main tools of analysis is the quasi 3D through flow computer code CAPTUR, which enables the calculation of all the aerothermodynamic parameters in a steam turbine. The last development that has been performed on CAPTUR is the extension to a calculation of a flow within a turbine operating under partial admission. For such turbines, it is now possible to calculate an internal flow field, and determine the efficiency, in a much more accurate way than with previous methods, which consist in an arbitrary efficiency correction on an averaged 1D flow calculation. From the aerodynamic point of view, partial admission involves specific losses in the first stage, then expansion and turbulent mixing just downstream of the first stage. Losses in the first stage are of very different types: windage, pumping and expansion at the ends of an admission sector. Their values have been estimated, with help of experimental results, and then expressed as a slow down coefficient applied to the relative velocity at the blade outlet. As for the flow downstream the first stage, a computational analysis has been made with specific 2D and 3D codes. It has led to define the numerical treatment established in the CAPTUR code. Some problems had to be solved to make compatible a quasi 3D formulation, making an average in the azimutal direction and using a streamline curvature method, with an absolute 3D phenomenon. Certain limitations of the working conditions were first adopted, but a generalization is on hand. The calculation of a nuclear HP steam turbine operating under partial admission has been performed. Calculation results are in good accordance with tests results, especially as regards the expansion line along the stages. The code CAPTUR will be particularly useful for the calculation

BWR type reactor system

International Nuclear Information System (INIS)

Morooka, Shin-ichi.

1980-01-01

Purpose: To reduce the internal structure in a reactor by rapidly and efficiently transferring heat generated in a reactor core out of the reactor and eliminating the danger of radiation exposure. Constitution: Steam generated in a pressure vessel is introduced into heat pipe group by inserting the heat pipe group into the steam dome of the pressure vessel. The introduced steam is condensed in the heat pipes to transfer the heat of the steam to the heat pipe group. The transferred heat is transmitted to a heat exchanger provided out of a containment vessel to generate steam to operate a turbine. Thus, it is not necessary to introduce the steam including radioactive substance externally and can remove only the heat so as to carry out the desired purpose. (Kamimura, M.)

Analisis Bahaya dengan Metode Hazop dan Manajemen Risiko pada Steam Turbine PLTU di Unit 5 Pembangkitan Listrik Paiton (PT. YTL Jawa Timur

Directory of Open Access Journals (Sweden)

Erna Zulfiana

2013-09-01

Full Text Available Steam turbine beroperasi pada temperatur dan tekanan uap yang tinggi sehingga keamanan proses harus dijaga agar tidak terjadi bahaya yang menimbulkan risiko. Untuk analisis dan identifikasi bahaya digunakan metode HAZOP yang selanjutnya melakukan manajemen resiko berupa emergency respon plan berdasarkan bahaya yang mungkin terjadi pada PLTU. Identifikasi bahaya dengan metode HAZOP dilakukan dengan penentuan 4 node pada steam turbine yaitu HP Turbine, IP Turbine, LP Turbine 1 dan LP Turbine 2, penentuan guideword dan deviasi berdasarkan control chart data proses transmitter di setiap node, dan untuk estimasi likelihood berdasarkan nilai MTTF tiap transmitter. ERP pada steam turbine dibuat untuk kejadian kebakaran karena berisiko tinggi dan kemungkinan besar terjadi serta dapat menyebabkan bahaya lain seperti ledakan dsb. Dari penelitian ini diketahui kondisi yang paling berbahaya pada steam turbine adalah kondisi high pressure yang diketahui dari risk matrix pressure trasnmitter pada 4 node yang bernilai high dan ekstrim yang dapat menyebabkan turbin mengalami overspeed. Rekomendasi untuk menanggulangi bahaya tersebut antara lain pemasangan pressure alarm, simulasi automatic turbine test, pemeriksaan turbine overspeed protection serta kalibrasi maupun pengecekan pada pressure trasnmitter tersebut.

Steam line break analysis in CAREM-25 reactor

International Nuclear Information System (INIS)

Zanocco, Pablo; Gimenez, Marcelo O.; Vertullo, Alicia; Schlamp, Miguel A.; Garcia, Alicia E.

2000-01-01

The main objective of this report is to analyze the reactor response during a steam line break postulated accident with RELAP5, a plant code using a separated flow model. The steam line break caused a rapid blowdown of the secondary coolant increasing the heat removal in the steam generator. As a consequence and due to reactor features the core power is also increased. As maximum removed power in the secondary side is highly dependant on the total water volume evaporated during the accident a detailed model of feed water and outlet steam pipes is provided. Different cases are analyzed with and without feedwater system and considering the fail or success of the First Shutdown System. In all the sequences the DNBR and CPR remain above the minimum safety values established by design. Further calculations concerning depressurization ramps and steam generator feed water pumps response during depressurization are advised. (author)

Steam Line Break Analysis in CAREM-25 Reactor

International Nuclear Information System (INIS)

Zanocco, Pablo; Gimenez, Marcelo; Vertullo, Alicia; Garcia, A; Schlamp, Miguel

2000-01-01

The main objective of this report is to analyze the reactor response during a steam line break postulated accident with RELAP5, a plant code using a separated flow model.The steam line break caused a rapid blowdown of the secondary coolant increasing the heat removal in the steam generator.As a consequence and due to reactor features the core power is also increased.As maximum removed power in the secondary side is highly dependant on the total water volume evaporated during the accident a detailed model of feed water and outlet steam pipes is provided.Different cases are analyzed with and without feedwater system and considering the fail or success of the First Shutdown System.In all the sequences the DNBR and CPR remain above the minimum safety values established by design.Further calculations concerning depressurization ramps and steam generator feed water pumps response during depressurization are advised

Nuclear reactor steam depressurization valve

International Nuclear Information System (INIS)

Moore, G.L.

1991-01-01

This patent describes improvement in a nuclear reactor plant, an improved steam depressurization valve positioned intermediate along a steam discharge pipe for controlling the venting of steam pressure from the reactor through the pipe. The improvement comprises: a housing including a domed cover forming a chamber and having a partition plate dividing the chamber into a fluid pressure activation compartment and a steam flow control compartment, the valve housing being provided with an inlet connection and an outlet connection in the steam flow control compartment, and a fluid duct in communication with a source of fluid pressure for operating the valve; a valve set mounted within the fluid flow control compartment comprising a cylindrical section surrounding the inlet connection with one end adjoining the connection and having a radially projecting flange at the other end with a contoured extended valve sealing flange provided with an annular valve sealing member, and a valve cylinder traversing the partition plate and reciprocally movable within an opening in the partition plate with one terminal and extending into the fluid pressure activation compartment and the other terminal end extending into the steam flow control compartment coaxially aligned with the valve seat surrounding the inlet connection, the valve cylinder being surrounded by two bellow fluid seals and provided with guides to inhibit lateral movement, an end of the valve cylinder extending into the fluid flow control compartment having a radially projecting flange substantially conterminous with the valve seat flange and having a contoured surface facing and complimentary to the contoured valve seating surface whereby the two contoured valve surfaces can meet in matching relationship, thus providing a pressure actuated reciprocatable valve member for making closing contact with the valve seat and withdrawing therefrom for opening fluid flow through the valve

Modification of the algorithm for steam turbine control under loading drop

International Nuclear Information System (INIS)

Nikitin, Yu.V.; Mirnyj, V.A.; Gritsenko, V.N.; Nesterov, L.V.

1989-01-01

Problem related to powerful steam turbine control in case of emergency loading drop is considered. Two laws of control creating conditions for qualitative operation of control system under conditions considered are compared. The system of turbine control comprises the turbine major actuating mechanisms (electrohydraulic transducer, high-pressure servomotor, cut-off slide valve) actuating mechanisms of pulse discharge channel (low-pressure servomotor cut-off slide valve, low-pressure servomotor) and regulator. The frequency of the turbine rotor rotation is the parameter to be controlled in the mode of loading drop. The algorithms considered are based on linear variant of the optimal control theory. One of them is realized in electrohydraulic system of the K-750-65/3000 turbine control at the Ignalinsk NPP

Study on steam separation in steam generators of a NPP with the WWER-440 reactors

International Nuclear Information System (INIS)

Dmitriev, A.I.; Kolzov, Yu.V.; Titov, V.F.; Dubrovin, A.V.; Ilyushin, V.F.; Volkov, A.P.

1977-01-01

The separation characteristics as well as the actual level position in steam generators with and without a submerged holy sheet have been determined at a WWER-440 reactor nuclear power plant. It has been shown, that without changing the design of steam generators their load at the WWER-440 reactor nuclear power plant can be increased by about 10%. In this case the vapour humidity does not exceed the permissible value equal to 0.25%. The submerged holy sheet considerably decreases load irregularity and swelling of the water-steam mixture layer

Reactor water injection facility

Energy Technology Data Exchange (ETDEWEB)

Yoshikawa, Kazuhiro; Kinoshita, Shoichiro

1997-05-02

A steam turbine and an electric generator are connected by way of a speed convertor. The speed convertor is controlled so that the number of rotation of the electric generator is constant irrespective of the speed change of the steam turbine. A shaft coupler is disposed between the turbine and the electric generator or between the turbine and a water injection pump. With such a constitution, the steam turbine and the electric generator are connected by way of the speed convertor, and since the number of revolution of the electric generator is controlled to be constant, the change of the number of rotation of the turbine can be controlled irrespective of the change of the number of rotation of the electric generator. Accordingly, the flow rate of the injection water from the water injection pump to a reactor pressure vessel can be controlled freely thereby enabling to supply stable electric power. (T.M.)

Studies on high temperature research reactor in China

Energy Technology Data Exchange (ETDEWEB)

Xu Yuanhui; Zuo Kanfen [Institute of Nuclear Energy Technology, Tsinghua Univ., Beijing (China)

1999-08-01

China recognises the advantages of Modular HTGRs and has chosen Modular HTGRs as one of advanced reactors to be developed for the further intensive utilisation of nuclear power in the next century. In energy supply systems of the next century, HTGR is supposed to serve: 1. as supplement to water-cooled reactors for electricity generation and 2. as environmentally friendly heat source providing process heat at different temperatures for various applications like heavy oil recovery, coal gasification and liquefaction, etc.. The 10 MW High Temperature Gas-cooled Reactor (HTR-10) is a major project in the energy sector of the Chinese National High Technology Programme as the first step of development of Modular HTGRs in China. Its main objectives are: 1. to acquire know-how in the design, construction and operation of HTGRs, 2. to establish an irradiation and experimental facility, 3. to demonstrate the inherent safety features of Modular HTGR, 4. to test electricity and heat co-generation and closed cycle gas turbine technology and 5. to do research and development work on the nuclear process heat application. Now the HTR-10 is being constructed at the site of Institute of Nuclear Energy Technology (INET). The HTR-10 project is to be carried out in two phases. In the first phase, the reactor with an coolant outlet temperature of 700degC will be coupled with a steam generator providing steam for a steam turbine cycle which works on an electricity and heat co-generation basis. In the second phase, the reactor coolant outlet temperature is planned to be raised to 900degC. As gas turbine cycle and a steam reformer will be coupled to the reactor in addition to the steam turbine cycle. (author)

Studies on high temperature research reactor in China

International Nuclear Information System (INIS)

Xu Yuanhui; Zuo Kanfen

1999-01-01

China recognises the advantages of Modular HTGRs and has chosen Modular HTGRs as one of advanced reactors to be developed for the further intensive utilisation of nuclear power in the next century. In energy supply systems of the next century, HTGR is supposed to serve: 1. as supplement to water-cooled reactors for electricity generation and 2. as environmentally friendly heat source providing process heat at different temperatures for various applications like heavy oil recovery, coal gasification and liquefaction, etc.. The 10 MW High Temperature Gas-cooled Reactor (HTR-10) is a major project in the energy sector of the Chinese National High Technology Programme as the first step of development of Modular HTGRs in China. Its main objectives are: 1. to acquire know-how in the design, construction and operation of HTGRs, 2. to establish an irradiation and experimental facility, 3. to demonstrate the inherent safety features of Modular HTGR, 4. to test electricity and heat co-generation and closed cycle gas turbine technology and 5. to do research and development work on the nuclear process heat application. Now the HTR-10 is being constructed at the site of Institute of Nuclear Energy Technology (INET). The HTR-10 project is to be carried out in two phases. In the first phase, the reactor with an coolant outlet temperature of 700degC will be coupled with a steam generator providing steam for a steam turbine cycle which works on an electricity and heat co-generation basis. In the second phase, the reactor coolant outlet temperature is planned to be raised to 900degC. As gas turbine cycle and a steam reformer will be coupled to the reactor in addition to the steam turbine cycle. (author)

Combined heat and power plants with parallel tandem steam turbines; Smaaskalig kraftvaerme med parallellkopplade tandemturbiner

Energy Technology Data Exchange (ETDEWEB)

Steinwall, Pontus; Norstroem, Urban; Pettersson, Camilla; Oesterlin, Erik

2004-12-01

We investigate the technical and economical conditions for a concept with parallel coupled tandem turbines in small scale combined heat and power plants fired with bio-fuel and waste. Performance and heat production costs at varying electricity prices for the concept with two smaller tandem coupled steam turbines has been compared to the traditional concept with one single multi-staged turbine. Three different types of plants have been investigated: - Bio fuelled CHP plant with thermal capacity of 15 MW{sub th}; - Waste fired CHP plant with thermal capacity of 20 MW{sub th}; - Bio fuelled CHP plant with thermal capacity of 25 MW{sub th}. The simple steam turbines (Curtis turbines) used in the tandem arrangement has an isentropic efficiency of about 49 to 53% compared to the multi-staged steam turbines with isentropic efficiency in the range of 59% to 81%. The lower isentropic efficiency for the single staged turbines is to some extent compensated at partial load when one of the two turbines can be shut down leading to better operational conditions for the one still in operation. For concepts with saturated steam at partial load below 50% the tandem arrangements presents higher electricity efficiency than the conventional single turbine alternative. The difference in annual production of electricity is therefore less than the difference in isentropic efficiency for the two concepts. Production of electricity is between 2% and 42% lower for the tandem arrangements in this study. Investment costs for the turbine island has been calculated for the two turbine concepts and when the costs for turbines, generator, power transmission, condensing system, piping system, buildings, assembling, commissioning and engineering has been added the sum is about the same for the two concepts. For the bio-fuelled plant with thermal capacity of 15 MW{sub th} the turbine island amount to about 10-12 MSEK and about 13-15 MSEK for the waste fired plant with a thermal capacity of 20 MW

Design, development and operating experience with wet steam turbines

International Nuclear Information System (INIS)

Bolter, J.R.

1989-01-01

The paper first describes the special characteristics of wet steam units. It then goes on to discuss the principal features of the units manufactured by the author's company, the considerations on which the designs were based, and the development work carried out to validate them. Some of the design features such as the separator/reheater units and the arrangements for water extraction in the high pressure turbine are unconventional. An important characteristic of all nuclear plant is the combination of high capital cost and low fuel cost, and the consequent emphasis placed on high availability. The paper describes some service problems experienced with wet steam plant and how these were overcome with minimum loss of generation. The paper also describes a number of the developments for future wet steam plant which have evolved from these experiences, and from research and development programmes aimed at increasing the efficiency and reliability of both conventional and wet steam units. Blading, rotor construction and separator/reheater units are considered. (author)

A reflux capsule steam generator for sodium cooled reactors

International Nuclear Information System (INIS)

Lantz, E.

Pressurized water reactor plants at numerous sites have sustained significant leakage through their steam generators. The consequent shutdowns for repairs and replacements have damaged their economics. This experience suggests that if steam generators for liquid metal fast breeder reactors (LMFBR's) continue to be built as presently designed some of them will have similar problems. Because of their larger capital investment, the consequent damage to the economics of LMFBR's could be more serious. Reflux capsules provide a way to separate sodium from water and to reduce thermal stresses in steam generators for sodium cooled reactors. Their use would also eliminate the need for a primary heat exchanger and a secondary sodium loop pump. (author)

Generalised pole-placement control of steam turbine speed

Energy Technology Data Exchange (ETDEWEB)

Fernandez-del-Busto, R. [ITESM, Cuernavaca (Mexico). Div. de Ingenieria y Ciencias; Munoz, J. [ITESM, Xochimilco (Mexico). Div. de Ingenieria y Ciencias

1996-12-31

An application of a pole-placement self-tuning predictive control algorithm is developed to regulate speed of a power plant steam turbine model. Two types of system representation (CARMA and CARIMA) are used to test the control algorithm. Simulation results show that when using a CARMA model better results are produced. Two further comparisons are made when using a PI controller and a generalised predictive controller. (author)

Moving blade for steam turbines with axial flow

International Nuclear Information System (INIS)

Raschke, K.; Wehle, G.

1976-01-01

The invention concerns the improvement of the production of moving blades for steam turbines with axial flow, especially of multi-blades produced by welding of the top plates. It is proposed to weld the top plates before the moving blades are fitted into the rotor. Welding is this made much easier and can be carried out under protective gas and with better results. (UWI) [de

High-power condensation turbine application to district heating

International Nuclear Information System (INIS)

Virchenko, M.A.; Arkad'ev, B.A.; Ioffe, V.Yu.

1982-01-01

In general outline the role of condensation turbines in NPP district heating is considered. The expediency of expansion of central heating loading of turbines of operating as well as newly designed condensation power plants on the basis of the WWER-1000-type reactors is shown. The principle heat flowsheet of the 1000 MW power turbine is given. An advantage in using turbines with uncontrolled steam bleeding is pointed out [ru

Processing of Advanced Alloys for A-USC Steam Turbine Applications

Energy Technology Data Exchange (ETDEWEB)

Jablonski, P. D. [National Energy Technology Laboratory (NETL); Hawk, Jeffrey A. [National Energy Technology Laboratory (NETL); Cowen, Christopher J. [National Energy Technology Laboratory (NETL); Maziasz, Philip J [ORNL

2010-01-01

The high-temperature components within conventional supercritical coal-fired power plants are manufactured from ferritic/martensitic steels. To reduce greenhouse-gas emissions, the efficiency of pulverized coal steam power plants must be increased to as high a temperature and pressure as feasible. The proposed steam temperature in the DOE/NETL Advanced Ultra Supercritical power plant is high enough (760 C) that ferritic/martensitic steels will not work for the majority of high-temperature components in the turbine or for pipes and tubes in the boiler due to temperature limitations of this class of materials. Thus, Ni-based superalloys are being considered for many of these components. Off-the-shelf forged nickel alloys have shown good promise at these temperatures, but further improvements can be made through experimentation within the nominal chemistry range as well as through thermomechanical processing and subsequent heat treatment. However, cast nickel-based superalloys, which possess high strength, creep resistance, and weldability, are typically not available, particularly those with good ductility and toughness that are weldable in thick sections. To address those issues related to thick casting for turbine casings, for example, cast analogs of selected wrought nickel-based superalloys such as alloy 263, Haynes 282, and Nimonic 105 have been produced. Alloy design criteria, melt processing experiences, and heat treatment are discussed with respect to the as-processed and heat-treated microstructures and selected mechanical properties. The discussion concludes with the prospects for full-scale development of a thick section casting for a steam turbine valve chest or rotor casing.

Oxygen transport membrane reactor based method and system for generating electric power

Science.gov (United States)

Kelly, Sean M.; Chakravarti, Shrikar; Li, Juan

2017-02-07

A carbon capture enabled system and method for generating electric power and/or fuel from methane containing sources using oxygen transport membranes by first converting the methane containing feed gas into a high pressure synthesis gas. Then, in one configuration the synthesis gas is combusted in oxy-combustion mode in oxygen transport membranes based boiler reactor operating at a pressure at least twice that of ambient pressure and the heat generated heats steam in thermally coupled steam generation tubes within the boiler reactor; the steam is expanded in steam turbine to generate power; and the carbon dioxide rich effluent leaving the boiler reactor is processed to isolate carbon. In another configuration the synthesis gas is further treated in a gas conditioning system configured for carbon capture in a pre-combustion mode using water gas shift reactors and acid gas removal units to produce hydrogen or hydrogen-rich fuel gas that fuels an integrated gas turbine and steam turbine system to generate power. The disclosed method and system can also be adapted to integrate with coal gasification systems to produce power from both coal and methane containing sources with greater than 90% carbon isolation.

Analysis of steam explosions in plate-type, uranium-aluminum fuel test reactors

International Nuclear Information System (INIS)

Taleyarkhan, R.P.

1989-01-01

The concern over steam explosions in nuclear reactors can be traced to prompt critical nuclear excursions in aluminum-clad/fueled test reactors, as well as to explosive events in aluminum, pulp, and paper industries. The Reactor Safety Study prompted an extensive analytical and experimental effort for over a decade. This has led to significant improvements in their understanding of the steam explosion issue for commercial light water reactors. However, little progress has been made toward applying the lessons learned from this effort to the understanding and modeling of steam explosion phenomena in aluminum-clad/fueled research and test reactors. The purposes of this paper are to (a) provide a preliminary analysis of the destructive events in test reactors, based on current understandings of steam explosions; (b) provide a proposed approach for determining the likelihood of a steam explosion event under scenarios in which molten U-Al fuel drops into a water-filled cavity; and (c) present a benchmarking study conducted to estimate peak pressure pulse magnitudes

Advanced boiling water reactor

International Nuclear Information System (INIS)

Nishimura, N.; Nakai, H.; Ross, M.A.

1999-01-01

In the Boiling Water Reactor (BWR) system, steam generated within the nuclear boiler is sent directly to the main turbine. This direct cycle steam delivery system enables the BWR to have a compact power generation building design. Another feature of the BWR is the inherent safety that results from the negative reactivity coefficient of the steam void in the core. Based on the significant construction and operation experience accumulated on the BWR throughout the world, the ABWR was developed to further improve the BWR characteristics and to achieve higher performance goals. The ABWR adopted 'First of a Kind' type technologies to achieve the desired performance improvements. The Reactor Internal Pump (RIP), Fine Motion Control Rod Drive (FMCRD), Reinforced Concrete Containment Vessel (RCCV), three full divisions of Emergency Core Cooling System (ECCS), integrated digital Instrumentation and Control (I and C), and a high thermal efficiency main steam turbine system were developed and introduced into the ABWR. (author)

Integration of steam injection and inlet air cooling for a gas turbine generation system

International Nuclear Information System (INIS)

Wang, F.J.; Chiou, J.S.

2004-01-01

The temperature of exhaust gases from simple cycle gas turbine generation sets (GENSETs) is usually very high (around 500 deg. C), and a heat recovery steam generator (HRSG) is often used to recover the energy from the exhaust gases and generate steam. The generated steams can be either used for many useful processes (heating, drying, separation etc.) or used back in the power generation system for enhancing power generation capacity and efficiency. Two well-proven techniques, namely steam injection gas turbine (STIG) and inlet air cooling (IAC) are very effective features that can use the generated steam to improve the power generation capacity and efficiency. Since the energy level of the generated steam needed for steam injection is different from that needed by an absorption chiller to cool the inlet air, a proper arrangement is required to implement both the STIG and the IAC features into the simple cycle GENSET. In this study, a computer code was developed to simulate a Tai power's Frame 7B simple cycle GENSET. Under the condition of local summer weather, the benefits obtained from the system implementing both STIG and IAC features are more than a 70% boost in power and 20.4% improvement in heat rate

Cogeneration steam turbine plant for district heating of Berovo (Macedonia)

International Nuclear Information System (INIS)

Armenski, Slave; Dimitrov, Konstantin

2000-01-01

A plant for combined heat and electric power production, for central heating of the town Berovo (Macedonia) is proposed. The common reason to use a co-generation unit is the energy efficiency and a significant reduction of environmental pollution. A coal dust fraction from B rik' - Berovo coal mine is the main energy resource for cogeneration steam turbine plant. The heat consumption of town Berovo is analyzed and determined. Based on the energy consumption of a whole power plant, e. i. the plant for combined and simultaneous production of power is proposed. All necessary facilities of cogeneration plant is examined and determined. For proposed cogeneration steam turbine power plant for combined heat and electric production it is determined: heat and electric capacity of the plant, annually heat and electrical quantity production and annually coal consumption, the total investment of the plant, the price of both heat and electric energy as well as the pay back period. (Authors)

The taking into consideration of reliability in the design of steam turbines

International Nuclear Information System (INIS)

Brazzini, Robert; Chaboseau, J.; Mathey, J.

1976-01-01

Improvement of the quality of steam turbines is the object of continuous effort undertaken a long time ago. The turbines used in nuclear power stations, do not constitute a technical novation as compared to those which equip the 'conventional' type of power station. The specific conditions of the nuclear have nevertheless revealed anxieties which were not so acute in the case of conventional applications (intrinsic safety versus runaway risks, the operating surveillance of safety components, protection against corrosion by wet steam) and which reliability studies have been led to take into account. An example is given of the work carried out in this sense by describing the reliability studies devoted to the protection system of turbogenerator sets against overspeeds [fr

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 5: Combined gas-steam turbine cycles. [energy conversion efficiency in electric power plants

Science.gov (United States)

Amos, D. J.; Foster-Pegg, R. W.; Lee, R. M.

1976-01-01

The energy conversion efficiency of gas-steam turbine cycles was investigated for selected combined cycle power plants. Results indicate that it is possible for combined cycle gas-steam turbine power plants to have efficiencies several point higher than conventional steam plants. Induction of low pressure steam into the steam turbine is shown to improve the plant efficiency. Post firing of the boiler of a high temperature combined cycle plant is found to increase net power but to worsen efficiency. A gas turbine pressure ratio of 12 to 1 was found to be close to optimum at all gas turbine inlet temperatures that were studied. The coal using combined cycle plant with an integrated low-Btu gasifier was calculated to have a plant efficiency of 43.6%, a capitalization of $497/kW, and a cost of electricity of 6.75 mills/MJ (24.3 mills/kwh). This combined cycle plant should be considered for base load power generation.

Evaluation of steam as a potential coolant for nonbreeding blanket designs

International Nuclear Information System (INIS)

Stevens, H.C.; Misra, B.; Youngdahl, C.K.

1978-01-01

A steam-cooled nonbreeding blanket design has been developed as an evolution of the Argonne Experimental Power Reactor (EPR) studies. This blanket concept complete with maintenance considerations is to function at temperatures up to 650 0 C utilizing nickel-based alloys such as Inconel 625. Thermo-mechanical analyses were carried out in conjunction with thermal hydraulic analysis to determine coolant chennel arrangements that permit delivery of superheated steam at 500 0 C directly to a modern fossil plant-type turbine. A dual-cycle system combining a pressurized water circuit coupled with a superheated steam circuit can produce turbine plant conversion efficiencies approaching 41.5%

FUNDAMENTALS OF THE THEORY OF VENTILLATION PROCESSES IN THE STEAM TURBINES TPP

Directory of Open Access Journals (Sweden)

V. M. Neuimin

2015-01-01

Full Text Available  The article proposes the theoretical framework of ventilation processes emerging and going on in the stages of TPP steam turbines during the operating regimes with small-quantity volumetric flow rates in the low-pressure cylinder. The basic theory includes new physicomathematical models for estimating the ventilating capacity losses and ventilation heatings-up of the steam and the air-gas channel of the turbine; search and investigation of the factors causing the increased momental loads on the blade wheels of the finale stages which are likely to lead to destruction of the rotating blades. The paper renders the practical results of utilizing the theoretical framework of ventilation processes.The author obtains a new mathematical relation for high-accuracy assessment of the ventilating capacity losses accounting for all the diversification of parameters defining the level of these losses (it is established that the Coriolis force contributes twice as much to the ventilating capacity losses as the centrifugal force. Seven ordinary formulae obtained on its basis provide a separate stage ventilation-losses immediate evaluation (with rotation blades of the finale stage not unwinding from the turning, with rotation blades of the finale and intermediate stages unwinding from the turning, in the turbine altogether-vapor-evacuated including by readings of the regular instruments located at the connecters of the exhaust part of the lowpressure cylinder.As the cornerstone of the new ventilation heating-up evaluation system the author lays two experimentally established facts: the ventilating capacity losses are practically constant at working steam negligible volumetric flow rates; symmetrical ventilating flows in the blade channel mingle entirely to the moment of their split up at the periphery. This renders possible estimating the complete enthalpy increment of the steam being discharged from a stage in relation to the enthalpy of the steam being

Improvement of steam separator in boiling water reactors

Energy Technology Data Exchange (ETDEWEB)

Schaefer, Jan Peter; Cremer, Ingo; Lorenz, Maik [AREVA GmbH, Erlangen (Germany)

2013-07-01

The potential to improve the function of the steam separator is identified and explored by scaled air-water tests and validated CFD calculations. It can be outlined that requirements on a modern steam separator for BWR plants will be fulfilled, combined with very good operational experience of the existing separator designs (e.g. material, layout). With the new steam separator design, modern high performance fuel assembly designs can be used for various core loading strategies (e.g. low leakage). This allows an increased thermal power of up to +50 % for the fuel element clusters in the center of the core with high radial peaking factors. In addition, any problems with unallowable high moisture at the turbine are solved with the new design, which have been identified for running BWR plants with the old steam separator design after applying new core loading patterns (e.g. after power uprates). A compatible steam separator design for all running BWRs is ready to launch. (orig.)

Thermal circuit and supercritical steam generator of the BGR-300 nuclear power plant

International Nuclear Information System (INIS)

Afanas'ev, B.P.; Godik, I.B.; Komarov, N.F.; Kurochnkin, Yu.P.

1979-01-01

Secondary coolant circuit and a steam generator for supercritical steam parameters of the BGR-300 reactor plant are described. The BGR-300 plant with a 300 MW(e) high-temperature gas-cooled fast reactor is developed as a pilot commercial plant. It is shown that the use of a supercritical pressure steam increases the thermal efficiency of the plant and descreases thermal releases to the environment, permits to use home-made commercial turbine plants of large unit power. The proposed supercritical pressure steam generator has considerable advantages from the viewpoint of heat transfer and hydrodynamical processes

Advanced steam cycles for light water reactors. Final report

International Nuclear Information System (INIS)

Mitchell, R.C.

1975-07-01

An appraisal of the potential of adding superheat to improve the overall LWR plant cycle performance is presented. The study assesses the economic and technical problems associated with the addition of approximately 500 0 F of superheat to raise the steam temperature to 1000 0 F. The practicality of adding either nuclear or fossil superheat to LWR's is reviewed. The General Electric Company Boiling Water Reactor (BWR) model 238-732 (BWR/6) is chosen as the LWR starting point for this evaluation. The steam conditions of BWR/6 are representative of LWR's. The results of the fossil superheat portion of the evaluation are considered directly applicable to all LWR's. In spite of the potential of a nuclear superheater to provide a substantial boost to the LWR cycle efficiency, nuclear superheat offers little promise of development at this time. There are difficult technical problems to resolve in the areas of superheat fuel design and emergency core cooling. The absence of a developed high integrity, high temperature fuel for operation in the steam/water environment is fundamental to this conclusion. Fossil superheat offers the potential opportunity to utilize fossil fuel supplies more efficiently than in any other mode of central station power generation presently available. Fossil superheat topping cycles evaluated included atmospheric fluidized beds (AFB), pressurized fluidized beds, pressurized furnaces, conventional furnaces, and combined gas/steam turbine cycles. The use of an AFB is proposed as the preferred superheat furnace. Fossil superheat provides a cycle efficiency improvement for the LWR of two percentage points, reduces heat rejection by 15 percent per kWe generated, increases plant electrical output by 54 percent, and burns coal with an incremental net efficiency of approximately 40 percent. This compares with a net efficiency of 36--37 percent which might be achieved with an all-fluidized bed fossil superheat plant design

Process for extracting residual heat and device for the ultimate absorption of heat for nuclear reactors

International Nuclear Information System (INIS)

Bernard, Lawrence Jr.

1980-01-01

This invention concerns a 'heat sink' or device for the ultimate absorption of heat for electric power stations using the most widespread thermal neutron nuclear reactors, namely 'light water' reactors such as boiling or pressurized water reactors. The residual heat given off by these reactors can be safely extracted with this method by using dry cooling. However, the invention does not concern the problems arising from the cooling of the steam used for actuating the steam turbine nor the cooling of the steam exhausted by the turbine or coming from it, but it does concern the 'safety' part of the nuclear power station in which the residual heat discharged in the reactor is controlled and dissipated [fr

The Effect of Condensing Steam Turbine Exhaust Hood Body Geometry on Exhaust Performance Efficiency

Science.gov (United States)

Gribin, V. G.; Paramonov, A. N.; Mitrokhova, O. M.

2018-06-01

The article presents data from combined numerical and experimental investigations of the effect that the overall dimensions of the exhaust hood of a steam turbine with an underslung condenser has on the aerodynamic losses in the hood. Owing to the properly selected minimum permissible overall dimensions of the exhaust hood, more efficient operation of this turbine component is achieved, better vibration stability of the turbine set shaft line is obtained, and lower costs are required for arranging the steam turbine plant in the turbine building. Experiments have shown that the main overall dimensions of the hood body have a determining effect on the exhaust hood flow path profile and on its aerodynamic performance. Owing to properly selected ratios between the exhaust hood body main sizes without a diffuser, a total loss coefficient equal to approximately unity has been obtained. By using an axial-radial diffuser, the energy loss can be decreased by 30-40% depending on the geometrical parameters and level of velocities in the inlet section of a hood having the optimal overall dimensions. By using the obtained results, it becomes possible to evaluate the overall dimensions necessary for achieving the maximal aerodynamic hood efficiency and, as a consequence, to obtain better technical and economic indicators of the turbine plant as a whole already at the initial stage of its designing. If a need arises to select overall dimensions smaller than their optimal values, the increase of energy loss can be estimated using the presented dependences. The cycle of investigations was carried out on the experimental setups available in the fundamental research laboratory of the Moscow Power Engineering Institute National University's Department of Steam and Gas Turbines with due regard to the operating parameters and similarity criteria.

Erosion-corrosion of structural materials of wet steam turbines

International Nuclear Information System (INIS)

Tomarov, G.V.

1989-01-01

A model of erosion-corrosion wear of elements of a wet steam zone and a condensate-feeding path of turbines is considered. It is shown that diffusion of impurities and corrosion products in pores of an oxide layer is the control mechanism under conditions of laminar flow of a media. Processes of mass transfer are controlling factors in turbulent flow

Operational Measurement of Stationary Characteristics and Positions of Shrouded Steam Turbine Blades

Czech Academy of Sciences Publication Activity Database

Procházka, Pavel; Vaněk, František

2016-01-01

Roč. 65, č. 5 (2016), s. 1079-1086 ISSN 0018-9456 Institutional support: RVO:61388998 Keywords : displacement measurement * turbomachine blades * steam turbines Subject RIV: BI - Acoustics Impact factor: 2.456, year: 2016

Compatibility of gas turbine materials with steam cooling

Energy Technology Data Exchange (ETDEWEB)

Desai, V.; Tamboli, D.; Patel, Y. [Univ. of Central Florida, Orlando, FL (United States)

1995-10-01

Gas turbines had been traditionally used for peak load plants and remote locations as they offer advantage of low installation costs and quick start up time. Their use as a base load generator had not been feasible owing to their poor efficiency. However, with the advent of gas turbines based combined cycle plants (CCPs), continued advances in efficiency are being made. Coupled with ultra low NO{sub x} emissions, coal compatibility and higher unit output, gas turbines are now competing with conventional power plants for base load power generation. Currently, the turbines are designed with TIT of 2300{degrees}F and metal temperatures are maintained around 1700{degrees}F by using air cooling. New higher efficiency ATS turbines will have TIT as high as 2700{degrees}F. To withstand this high temperature improved materials, coatings, and advances in cooling system and design are warranted. Development of advanced materials with better capabilities specifically for land base applications are time consuming and may not be available by ATS time frame or may prove costly for the first generation ATS gas turbines. Therefore improvement in the cooling system of hot components, which can take place in a relatively shorter time frame, is important. One way to improve cooling efficiency is to use better cooling agent. Steam as an alternate cooling agent offers attractive advantages because of its higher specific heat (almost twice that of air) and lower viscosity.

Presentation summary: Gas Turbine - Modular Helium Reactor (GT-MHR)

International Nuclear Information System (INIS)

2001-01-01

Numerous prototypes and demonstration plants have been constructed and operated beginning with the Dragon plant in the early 1960s. The MHTGR was the U.S. developed modular plant and underwent pre application review by NRC. The GT-MHR represents a further refinement on this concept with the steam cycle being replaced by a closed loop gas turbine (Brayton) cycle. Modular gas reactors and the GT-MHR represent a fundamental shift in reactor design and safety philosophy. The reactor system is contained in a 3 vessel, side-by-side arrangement. The reactor and a shutdown cooling system are in one vessel, and the gas turbine based power conversion system, including the generator, in a second parallel vessel. A more detailed look at the system shows the compact arrangement of gas turbine, compressors, recuperator, heat exchanges, and generator. Fueled blocks are stacked in three concentric rings with inert graphite blocks making up the inner and outer reflectors. Operating control rods are located outside the active core while startup control rods and channels for reserve shutdown pellets are located near the core center. Ceramic coated fuel is the key to the GT-MHR's safety and economics. A kernel of Uranium oxycarbide (or UO 2 ) is placed in a porous carbon buffer and then encapsulated in multiple layers of pyrolytic carbon and silicon carbide. These micro pressure vessels withstand internal pressures of up to 2,000 psi and temperatures of nearly 2,000 C providing extremely resilient containment of fission products under both normal operating and accident conditions. The fuel particles are blended in carbon pitch, forming fuel rods, and then loaded into holes within large graphite fuel elements. Fuel elements are stacked to form the core. Fuel particle testing in has repeatedly demonstrated the high temperature resilience of coated particle fuel to temperature approaching 2,000 C. As an conservative design goal, GT-MHR has been sized to keep maximum fuel temperatures

Reactor pressure elevation preventing device upon interruption of load

International Nuclear Information System (INIS)

Ota, Yasuo; Okukawa, Ryutaro.

1996-01-01

In a power load imbalance circuit of a steam turbine control device, a power load imbalance occurrence signal is outputted for a predetermined period of time upon occurrence of load interruption. A function for suppressing increase of number of rotation of a turbine due to load interruption is not disturbed, and the power load imbalance circuit is not operated at least after a primary peak where the number of rotation of the turbine is increased. Since a steam control valve flow rate demand signal and a turbine bypass valve flow rate demand signals are corporated subsequently to control the opening degree of the steam control valve and the turbine bypass valve, elevation of reactor pressure is always suppressed and maintained constant, as well as abrupt opening of the steam control valve due to cancel of the power load imbalance circuit when steam control valve opening demand is outputted can be prevented. (N.H.)

Process for resuperheating steam coming from the high-pressure stage of a turbine and device to bring into use this process

International Nuclear Information System (INIS)

Pacault, P.H.

1977-01-01

A process is described for resuperheating steam coming from the high pressure stage of a turbine fed by a steam generator, itself heated from a base thermal source. The resuperheating is done by desuperheating at least a part of the steam coming from the generator, taken from the inflow of the turbine high pressure stage, the desuperheated steam being condensed, partially at least, in a condensation exchanger forming a preliminary resuperheater [fr

Heat extraction from turbines of Czechoslovak nuclear power plants for district heating

International Nuclear Information System (INIS)

Drahy, J.

1985-01-01

Two design are described of SKODA extraction turbines for Czechoslovak nuclear power plants with WWER-440 and WWER-1000 reactors. 220 MW steam turbines were originally designed as pure condensation turbines with uncontrolled steam extraction. Optimal ways are now being sought for their use for heating hot water for district heating. For district heating of the town of Trnava, the nuclear power plant at Jaslovske Bohunice will provide a two-step heating of water from 70 to 120 degC with a heat supply of 60 MW th from one turbine unit. The ratio of obtained heat power to lost electric power is 5.08. Investigations showed the possibility of extracting 85 MW th of heat from uncontrolled steam extraction, this at three-step water heating from 60 to 145 degC, the ratio of gained and lost power being 7.14. Information is presented on the SKODA 220 MW turbine with steam extraction for heat supply purposes and on the 1000 MW turbine with 893 MW th heat extraction. The specifications of both types are given. (Pu)

Design and construction features of steam generators at a nuclear power station

International Nuclear Information System (INIS)

Chakrabarti, A.K.; Gupta, K.N.; Bapat, C.N.; Sharma, V.K.

1996-01-01

The Indian nuclear power programme is based on Pressurised Heavy Water Reactors (PHWRs) using natural uranium as fuel and heavy water as reactor coolant as well as moderator. The nuclear heat is generated in the fuel located in the pressure tubes. Pressurised heavy water in the primary heat transport (PHT) system is circulated through the tubes which picks up the heat from the fuel and transfers it to ordinary water in steam generators (SGs) to produce steam. The steam is used for providing power to the turbine. The steam generator is a critical equipment in the nuclear steam supply system (NSSS) of a nuclear reactor. SG tube surface area constitute about 80% of total primary circuit surface area. A typical value in a 220 MWe reactor is 9000 m 2 which can release considerable amount of corrosion products unless very low corrosion rates are achieved by proper design, material selection and water chemistry control. Design and construction features of SGs are given. 1 tab

Effects of surface roughness on deviation angle and performance losses in wet steam turbines

International Nuclear Information System (INIS)

Bagheri Esfe, H.; Kermani, M.J.; Saffar Avval, M.

2015-01-01

In this paper, effects of turbine blade roughness and steam condensation on deviation angle and performance losses of the wet stages are investigated. The steam is assumed to obey non-equilibrium thermodynamic model, in which abrupt formation of liquid droplets produces condensation shocks. An AUSM-van Leer hybrid scheme is used to solve two-phase turbulent transonic steam flow around turbine rotor tip sections. The dominant solver of the computational domain is taken to be the AUSM scheme (1993) that in regions with large gradients smoothly switches to van Leer scheme (1979). This guarantees a robust hybrid scheme throughout the domain. It is observed that as a result of condensation, the aerothermodymics of the flow field changes. For example for a supersonic wet case with exit isentropic Mach number M e,is  = 1.45, the deviation angle and total pressure loss coefficient change by 65% and 200%, respectively, when compared with dry case. It is also observed that losses due to surface roughness in subsonic regions are much larger than those in supersonic regions. Hence, as a practical guideline for maintenance sequences, cleaning of subsonic parts of steam turbines should be considered first. - Highlights: • Two-phase turbulent transonic steam flow is numerically studied in this paper. • As a result of condensation, aerothermodynamics of the flow field changes. • Surface roughness has almost negligible effect on deviation angle. • Surface roughness plays an important role in performance losses. • Contribution of different loss mechanisms for smooth and rough blades are computed.

Requirements of coolants in nuclear reactors

International Nuclear Information System (INIS)

Abass, O. A. M.

2014-11-01

This study discussed the purposes and types of coolants in nuclear reactors to generate electricity. The major systems and components associated with nuclear reactors are cooling system. There are two major cooling systems utilized to convert the heat generated in the fuel into electrical power. The primary system transfers the heat from the fuel to the steam generator, where the secondary system begins. The steam formed in the steam generator is transferred by the secondary system to the main turbine generator, where it s converted into electricity after passing through the low pressure turbine. There are various coolants used in nuclear reactors-light water, heavy water and liquid metal. The two major types of water-cooled reactors are pressurized water reactors (PWR) and boiling water reactors (BWR) but pressurized water reactors are more in the world. Also discusses this study the reactors and impact of the major nuclear accidents, in the April 1986 disaster at the Chernobyl nuclear power plant in Ukraine was the product operators, and in the March 2011 at the Fukushima nuclear power plant in Japan was the product of earthquake of magnitude 9.0, the accidents caused the largest uncontrolled radioactive release into the environment.(Author)

Processing of Advanced Cast Alloys for A-USC Steam Turbine Applications

Science.gov (United States)

Jablonski, Paul D.; Hawk, Jeffery A.; Cowen, Christopher J.; Maziasz, Philip J.

2012-02-01

The high-temperature components within conventional supercritical coal-fired power plants are manufactured from ferritic/martensitic steels. To reduce greenhouse-gas emissions, the efficiency of pulverized coal steam power plants must be increased to as high a temperature and pressure as feasible. The proposed steam temperature in the DOE/NETL Advanced Ultra Supercritical power plant is high enough (760°C) that ferritic/martensitic steels will not work for the majority of high-temperature components in the turbine or for pipes and tubes in the boiler due to temperature limitations of this class of materials. Thus, Ni-based superalloys are being considered for many of these components. Off-the-shelf forged nickel alloys have shown good promise at these temperatures, but further improvements can be made through experimentation within the nominal chemistry range as well as through thermomechanical processing and subsequent heat treatment. However, cast nickel-based superalloys, which possess high strength, creep resistance, and weldability, are typically not available, particularly those with good ductility and toughness that are weldable in thick sections. To address those issues related to thick casting for turbine casings, for example, cast analogs of selected wrought nickel-based superalloys such as alloy 263, Haynes 282, and Nimonic 105 have been produced. Alloy design criteria, melt processing experiences, and heat treatment are discussed with respect to the as-processed and heat-treated microstructures and selected mechanical properties. The discussion concludes with the prospects for full-scale development of a thick section casting for a steam turbine valve chest or rotor casing.

Model for transient simulation in a PWR steam circuit

International Nuclear Information System (INIS)

Mello, L.A. de.

1982-11-01

A computer code (SURF) was developed and used to simulate pressure losses along the tubes of the main steam circuit of a PWR nuclear power plant, and the steam flow through relief and safety valves when pressure reactors its thresholds values. A thermodynamic model of turbines (high and low pressure), and its associated components are simulated too. The SURF computer code was coupled to the GEVAP computer code, complementing the simulation of a PWR nuclear power plant main steam circuit. (Author) [pt

Control of internal packing seal clearances considering for shaft behavior during steam turbine operation

Energy Technology Data Exchange (ETDEWEB)

Pack, Min Sik; Lee, Si Yeon; Choi, Sung Choul; Lee, Jae Geun [Korea Plant Service and Engineering Co., Ltd., Seongnam (Korea, Republic of); Yang, Bo Suk [Pukyong National Univ., Busan (Korea, Republic of)

2004-07-01

This paper presents the characteristics of internal clearances for the interstage of blades and shaft gland seals on the steam turbine which are installed in tandem compound. Internal clearances was changed when the rotor turned in the cylindrical sleeve bearing due to the generation of oil film wedge. This presented concern is very useful to prevent the rubbing damage of seal edge between the fixed and moving parts in steam turbine due to the misalignment at the rotating and stationary parts. This method is applied for the unbalanced clearances distribution to the left and right sides in the turbine casing. A considerable amount of unbalanced clearances distribution trend is determined according to the rotating speed of rotor, size and type of journal bearing, oil viscosity, surface roughness of bearing and shaft, oil temperature, oil pressure and bearing load.

The T-100-12.8 family of cogeneration steam turbines: Yesterday, today, and tomorrow

Science.gov (United States)

Valamin, A. E.; Kultyshev, A. Yu.; Shibaev, T. L.; Sakhnin, Yu. A.; Stepanov, M. Yu.

2013-08-01

The T-100-12.8 turbine and its versions, a type of cogeneration steam turbines that is among best known, unique, and most widely used ones in Russia and abroad, are considered. A list of turbine design versions and quantities in which they were produced, their technical and economic indicators, design features, schematic solutions used in different design versions, and a list of solutions available in a comprehensive portfolio offered for modernizing type T-100-12.8 turbines are presented. Information about amounts in which turbines of the last version are supplied currently and supposed to be supplied soon is given.

Clinch river breeder reactor plant steam generator water quality

Energy Technology Data Exchange (ETDEWEB)

Van Hoesen, D; Lowe, P A

1975-07-01

The recent problems experienced by some LWR Steam Generators have drawn attention to the importance of system water quality and water/ steam side corrosion. Several of these reactor plants have encountered steam generator failures due to accelerated tube corrosion caused, in part, by poor water quality and corrosion control. The CRBRP management is aware of these problems, and the implications that they have for the Clinch River Breeder Reactor Plant (CPBRP) Steam Generator System (SGS). Consequently, programs are being implemented which will: (1) investigate the corrosion mechanisms which may be present in the CRBRP SGS; (2) assure steam generator integrity under design and anticipated off-normal water quality conditions; and (3) assure that the design water quality levels are maintained at all times. However, in order to understand the approach being used to examine this potential problem, it is first necessary to look at the CRBRP SGS and the corrosion mechanisms which may be present.

Clinch river breeder reactor plant steam generator water quality

International Nuclear Information System (INIS)

Van Hoesen, D.; Lowe, P.A.

1975-01-01

The recent problems experienced by some LWR Steam Generators have drawn attention to the importance of system water quality and water/ steam side corrosion. Several of these reactor plants have encountered steam generator failures due to accelerated tube corrosion caused, in part, by poor water quality and corrosion control. The CRBRP management is aware of these problems, and the implications that they have for the Clinch River Breeder Reactor Plant (CPBRP) Steam Generator System (SGS). Consequently, programs are being implemented which will: 1) investigate the corrosion mechanisms which may be present in the CRBRP SGS; 2) assure steam generator integrity under design and anticipated off-normal water quality conditions; and 3) assure that the design water quality levels are maintained at all times. However, in order to understand the approach being used to examine this potential problem, it is first necessary to look at the CRBRP SGS and the corrosion mechanisms which may be present

Power-generation method using combined gas and steam turbines

Energy Technology Data Exchange (ETDEWEB)

Liu, C; Radtke, K; Keller, H J

1997-03-20

The invention concerns a method of power generation using a so-called COGAS (combined gas and steam) turbine installation, the aim being to improve the method with regard to the initial costs and energy consumption so that power can be generated as cheaply as possible. This is achieved by virtue of the fact that air taken from the surrounding atmosphere is splint into an essentially oxygen-containing stream and an essentially nitrogen-containing stream and the two streams fed further at approximately atmospheric pressure. The essentially nitrogen-containing stream is mixed with an air stream to form a mixed nitrogen/air stream and the mixed-gas stream thus produced is brought to combustion chamber pressure in the compressor of the gas turbine, the combustion of the combustion gases in the combustion chamber of the gas turbine being carried out with the greater part of this compressed mixed-gas stream. (author) figs.

Computer codes for simulation of Angra 1 reactor steam generator

International Nuclear Information System (INIS)

Pinto, A.C.

1978-01-01

A digital computer code is developed for the simulation of the steady-state operation of a u-tube steam generator with natural recirculation used in Pressurized Water Reactors. The steam generator is simulated with two flow channel separated by a metallic wall, with a preheating section with counter flow and a vaporizing section with parallel flow. The program permits the changes in flow patterns and heat transfer correlations, in accordance with the local conditions along the vaporizing section. Various sub-routines are developed for the determination of steam and water properties and a mathematical model is established for the simulation of transients in the same steam generator. The steady state operating conditions in one of the steam generators of ANGRA 1 reactor are determined utilizing this programme. Global results obtained agree with published values [pt

Feasibility and application on steam injector for next-generation reactor

International Nuclear Information System (INIS)

Narabayashi, Tadashi; Ishiyama, Takenori; Miyano, Hiroshi; Nei, Hiromichi; Shioiri, Akio

1991-01-01

A feasibility study has been conducted on steam injector for a next generation reactor. The steam injector is a simple, compact passive device for water injection, such as Passive Core Injection System (PCIS) of Passive Containment Cooling System (PCCS), because of easy start-up without an AC power. An analysis model for a steam injector characteristics has been developed, and investigated with a visualized fundamental test for a two-stage Steam Injector System (SIS) for PCIS and a one-stage low pressure SIS for PCCS. The test results showed good agreement with the analysis results. The analysis and the test results showed the SIS could work over a very wide range of the steam pressure, and is applicable for PCIS or PCCS in the next generation reactors. (author)

For effective thermodynamic calculation of turbines flow-through by gas and steam

Energy Technology Data Exchange (ETDEWEB)

Fischer, S; Hultsch, M

1982-03-01

A programme system for the medium and multiple section calculation of axial-flow turbines is explained. It allows calculations of turbine flow-through by gas and steam at designing and partial load states. The algorithms are independent upon the formulation of thermodynamic function, so that the programmes can be used for any means of production. The highest accuracy and efficiency can be guaranteed by the use of formulations of thermodynamic functions of water.

Medium temperature carbon dioxide gas turbine reactor

International Nuclear Information System (INIS)

Kato, Yasuyoshi; Nitawaki, Takeshi; Muto, Yasushi

2004-01-01

A carbon dioxide (CO 2 ) gas turbine reactor with a partial pre-cooling cycle attains comparable cycle efficiencies of 45.8% at medium temperature of 650 deg. C and pressure of 7 MPa with a typical helium (He) gas turbine reactor of GT-MHR (47.7%) at high temperature of 850 deg. C. This higher efficiency is ascribed to: reduced compression work around the critical point of CO 2 ; and consideration of variation in CO 2 specific heat at constant pressure, C p , with pressure and temperature into cycle configuration. Lowering temperature to 650 deg. C provides flexibility in choosing materials and eases maintenance through the lower diffusion leak rate of fission products from coated particle fuel by about two orders of magnitude. At medium temperature of 650 deg. C, less expensive corrosion resistant materials such as type 316 stainless steel are applicable and their performance in CO 2 have been proven during extensive operation in AGRs. In the previous study, the CO 2 cycle gas turbomachinery weight was estimated to be about one-fifth compared with He cycles. The proposed medium temperature CO 2 gas turbine reactor is expected to be an alternative solution to current high-temperature He gas turbine reactors

Performance and environment as objectives in multi-criterion optimization of steam injected gas turbine cycles

International Nuclear Information System (INIS)

Kayadelen, Hasan Kayhan; Ust, Yasin

2014-01-01

Rapidly growing demand for gas turbines promotes research on their performance improvement and reducing their exhaust pollutants. Even small increments in net power or thermal efficiency and small changes in pollutant emissions have become significant concerns for both new designs and cycle modifications. To fulfill these requirements an accurate performance evaluation method which enables to see the effects on the exhaust gas composition is an important necessity. To fill this gap, a thermo-ecologic performance evaluation approach for gas turbine cycles with chemical equilibrium approximation which enables performance and environmental aspects to be considered simultaneously, is presented in this work. Steam injection is an effective modification to boost power and limit NO x emissions for gas turbine systems. Steam injection also increases thermal efficiency so less fuel is burnt to maintain the same power output. Because of its performance related and environmental advantages, presented approach is applied on the steam injected gas turbine cycle and a precise multi-criterion optimization is carried out for varying steam injection, as well as equivalence and pressure ratios. Irreversibilities and pressure losses are also considered. Effects of each parameter on the net work and thermal efficiency as well as non-equilibrium NO x and CO emissions are demonstrated. Precision improvement of the presented thermo-ecological model is shown and two main concerns; constant turbine inlet condition for higher net work output and constant net work output condition for lower fuel consumption are compared. - Highlights: • A thermodynamically precise performance estimation tool for GT cycles is presented. • STIG application is provided to show its flexibility for any GT cycle and diluents. • Constant TIT and net work output conditions have been compared and discussed. • The model provides results to evaluate economic and environmental aspects together. • It provides a

Molten salt fueled nuclear facility with steam-and gas turbine cycles of heat transformation

International Nuclear Information System (INIS)

Ananich, P.I.; Bunin, E.N.; Kazazyan, V.T.; Nemtsev, V.A.; Sikorin, S.N.

2001-01-01

The molten salt fueled nuclear facilities with fuel circulating in the primary circuit have a series of the potential advantages in comparison with the traditional thermal and fast reactors with solid fuel elements. These advantages are ensured by the possibility to receive effective neutron balance in the core, minimum margin reactivity, more deep fuel burnup, unbroken correctness of the fuel physical and chemical properties and by low prices of the fuel cycle. The neutron and thermal-physical calculations of the various variants of the MSFNF with steam-water and gas turbine power circuits and their technical and economical comparison are carried out in this article. Calculations of molten salt nuclear power plant with gas turbine power circuit have been carried out using chemically reacting working body ''nitrin'' (N304 + 1%NO). The molten salt fueled reactors with the thermal power near of 2300 MW with two fuel compositions have been considered. The base variant has been taken the design of NPP with VVER NP-1000 when comparing the results of the calculations. Its economical performances are presented in prices of 1990. The results of the calculations show that it is difficult to determine the advantages of any one of the variants considered in a unique fashion. But NPP with MSR possesses large reserves in the process of optimization of cycle and energy equipment parameters that can improve its technical and economical performances sufficiently. (author)

Improvement of testing techniques for inspecting steam turbine rotor in power plant

International Nuclear Information System (INIS)

Su, Yeong Shuenn; Wei, Chieng Neng; Wu, Chien Wen; Wu, Yung How

1997-01-01

Steam turbine rotor is important to the Utility industry, it degrades over time due to fatigue and corrosion under high temperature and high pressure environment. Periodic inspection is required in the wake of plant annual overhaul to ensure the integrity of turbine rotor. Non-Destructive Testing of turbine rotor is usually performed using magnetic particle testing with wet fluorescent magnetic particle. However, it is very difficult to ensure the reliability of inspection due to the limitation of using one NDT method only. The crack-susceptible areas, such as turbine blade, and blade root have high incidence of stress corrosion cracking, The blade root section is difficult to locate cracks because of the complex geometry which may cause inadequate magnetic field and poor accessibility. Improved inspection practices was developed by our Department, together with remaining life analysis, in maintaining the high availability of steam turbine rotor. The newly-developed inspection system based on the practical study of magnetic field strength distribution, quality of magnetic particle bath and a combination of different NDT methods with Eddy Current Testing using absolute pen-type coil and Visual Testing using reflective mirror to examine the key areas concerned are described. TPC' experience with the well-trained technicians together with the adequate inspection procedure in detecting blade-root flaws are also discussed in the paper. Many of these inspection improvement have been applied in the fields for several times and the inspection reliability has been enhanced substantially. Results are quite encouraging and satisfactory.

Heat balance calculation and feasibility analysis for initial startup of Fuqing nuclear turbine unit with non-nuclear steam

International Nuclear Information System (INIS)

He Liu; Xiao Bo; Song Yumeng

2014-01-01

Non-nuclear steam run up compared with nuclear steam run up, can verify the design, manufacture, installation quality of the unit, at the same time shorten the follow-up duration of the entire group ready to start debugging time. In this paper, starting from the first law of thermodynamics, Analyzed Heat balance Calculation and Feasibility analysis for Initial startup of Fuqing nuclear Turbine unit with Non-nuclear steam, By the above calculation, to the system requirements and device status on the basis of technical specifications, confirmed the feasibility of Non-nuclear steam running up in theory. After the implementation of the Non-nuclear turn of Fuqing unit, confirmed the results fit with the actual process. In summary, the Initial startup of Fuqing turbine unit with Non-nuclear steam is feasible. (authors)

Integration of a turbine expander with an exothermic reactor loop--Flow sheet development and application to ammonia production

International Nuclear Information System (INIS)

Greeff, I.L.; Visser, J.A.; Ptasinski, K.J.; Janssen, F.J.J.G.

2003-01-01

This paper investigates the direct integration of a gas turbine power cycle with an ammonia synthesis loop. Such a loop represents a typical reactor-separator system with a recycle stream and cold separation of the product from the recycle loop. The hot reaction products are expanded directly instead of raising steam in a waste heat boiler to drive a steam turbine. Two new combined power and chemicals production flow sheets are developed for the process. The flow sheets are simulated using the flow sheet simulator AspenPlus (licensed by Aspen Technology, Inc.) and compared to a simulated conventional ammonia synthesis loop. The comparison is based on energy as well as exergy analysis. It was found that the pressure ratio over the turbine expander plays an important role in optimisation of an integrated system, specifically due to the process comprising an equilibrium reaction. The inlet temperature to the reactor changes with changing pressure ratio, which in turn determines the conversion and consequently the heat of reaction that is available to produce power. In terms of the minimum work requirement per kg of product a 75% improvement over the conventional process could be obtained. The work penalty due to refrigeration needed for separation was also accounted for. Furthermore this integrated flow sheet also resulted in a decrease in exergy loss and the loss was more evenly distributed between the various unit operations. A detailed exergy analysis over the various unit operations proved to be useful in explaining the overall differences in exergy loss between the flow sheets

Influence of steam leakage through vane, gland, and shaft seals on rotordynamics of high-pressure rotor of a 1,000 MW ultra-supercritical steam turbine

Energy Technology Data Exchange (ETDEWEB)

Jiang, P.N. [Shanghai Jiao Tong University, Key Laboratory of Power Machinery and Engineering, Ministry of Education, School of Mechanical Engineering, Shanghai (China); Shanghai Turbine Company, Department of R and D, Shanghai (China); Wang, W.Z.; Liu, Y.Z. [Shanghai Jiao Tong University, Key Laboratory of Power Machinery and Engineering, Ministry of Education, School of Mechanical Engineering, Shanghai (China); Meng, G. [Shanghai Jiao Tong University, State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai (China)

2012-02-15

A comparative analysis of the influence of steam leakage through vane, gland, and shaft seals on the rotordynamics of the high-pressure rotor of a 1,000 MW ultra-supercritical steam turbine was performed using numerical calculations. The rotordynamic coefficients associated with steam leakage through the three labyrinth seals were calculated using the control-volume method and perturbation analysis. A stability analysis of the rotor system subject to the steam forcing induced by the leakage flow was performed using the finite element method. An analysis of the influence of the labyrinth seal forcing on the rotordynamics was carried out by varying the geometrical parameters pertaining to the tooth number, seal clearance, and inner diameter of the labyrinth seals, along with the thermal parameters with respect to pressures and temperatures. The results demonstrated that the steam forcing with an increase in the length of the blade for the vane seal significantly influences the rotordynamic coefficients. Furthermore, the contribution of steam forcing to the instability of the rotor is decreased and increased with increases in the seal clearance and tooth number, respectively. The comparison of the rotordynamic coefficients associated with steam leakage through the vane seal, gland seal, and shaft seal convincingly disclosed that, although the steam forcing attenuates the stability of the rotor system, the steam turbine is still operating under safe conditions. (orig.)

Evaluation on mechanical and corrosion properties of steam generator tubing materials

International Nuclear Information System (INIS)

Kim, In Sup; Lee, Byong Whi; Lee, Sang Kyu; Lee, Young Ho; Kim, Jun Whan; Lee, Ju Seok; Kwon, Hyuk Sang; Kim, Su Jung

1998-06-01

Steam generator is one of the major components of nuclear reactor pressure boundary. It's main function os transferring heat which generated in the reactor to turbine generator through steam generator tube. In these days, steam generator tubing materials of operating plant are used Inconel 600 alloys. But according to the operation time, there are many degradation phenomena which included mechanical damage due to flow induced vibration and corrosion damage due to PWSCC, IGA/SCC and pitting etc. Recently Inconel 690 alloys are selected as new and replacement steam generator tubes for domestic nuclear power plant. But there are few study about mechanical and corrosion properties of Inconel 600 and 690. The objectives of this study is to evaluate and compare mechanical and corrosion propertied of steam generator tube materials

Evaluation on mechanical and corrosion properties of steam generator tubing materials

Energy Technology Data Exchange (ETDEWEB)

Kim, In Sup; Lee, Byong Whi; Lee, Sang Kyu; Lee, Young Ho; Kim, Jun Whan; Lee, Ju Seok; Kwon, Hyuk Sang; Kim, Su Jung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1998-06-15

Steam generator is one of the major components of nuclear reactor pressure boundary. It's main function os transferring heat which generated in the reactor to turbine generator through steam generator tube. In these days, steam generator tubing materials of operating plant are used Inconel 600 alloys. But according to the operation time, there are many degradation phenomena which included mechanical damage due to flow induced vibration and corrosion damage due to PWSCC, IGA/SCC and pitting etc. Recently Inconel 690 alloys are selected as new and replacement steam generator tubes for domestic nuclear power plant. But there are few study about mechanical and corrosion properties of Inconel 600 and 690. The objectives of this study is to evaluate and compare mechanical and corrosion propertied of steam generator tube materials.

Avoiding failures of steam turbine discs by automated ultrasonic inspections

International Nuclear Information System (INIS)

Morton, J.; Bird, C.R.

1994-01-01

Under certain conditions, stress corrosion cracking can cause catastrophic failure of steam turbine discs. Nuclear Electric has developed a range of inspection techniques for disc keyways, bores, buttons and blade attachments and has accumulated substantial experience on their use on plant. This paper gives examples of the techniques used and discusses the strengths and weaknesses of the techniques applied

Experience with and techniques of diagnosing power plant steam turbines without dismantling

International Nuclear Information System (INIS)

Drapal, A.; Kopecek, K.

1987-01-01

Within the framework of vibration diagnostics of steam turbines at the Dukovany nuclear power plant the following factors were monitored: the summation signal of vibrations (usually the path of vibration movement), the time course of the vibration and the phase angle. In non-steady states also run-in and run-out curves, the absolute vibration of bearing stands and the relative vibration of the rotor are monitored. The method has so far not allowed to diagnose failures of antifriction bearings, loose parts, some gear box defects, the development of cracks in vanes, radial cracks in the disk, etc. Briefly characterized is the portable equipment which is available at the Dukovany nuclear power plant for vibration diagnostics of steam turbines. Suggestions are made for completing the system for monitoring service life, operation economics, the diagnosis of control circuits, etc. (Z.M.)

Welding repair of the steam and gas turbines rotors made of Cr-Mo-V steel

International Nuclear Information System (INIS)

Mazur, Z.; Kubiak, J.; Hernandez, A.

1999-01-01

An analysis of typical steam turbine and gas turbine rotor failures is carried out. On the base of the rotors different failure causes and their mode of occurring, an evaluation of the weldability of the Cr-Mo-V steels and the classification of the common turbine rotors repair possibilities is presented. The developing of specific in-situ welding repair process of the damaged 20.65 MW gas turbine rotor is described. After repair, the rotor was put back into service. (Author) 15 refs

Steam turbine controls and their integration into power plants

International Nuclear Information System (INIS)

Kure-Jensen, J.; Hanisch, R.

1989-01-01

The main functions of a modern steam turbine control system are: speed and acceleration control during start-up; initialization of generator excitation; synchronization and application of load; pressure control of various forms: inlet, extraction backpressure, etc.; unloading and securing of the turbine; sequencing of the above functions under constraint of thermal stress overspeed protection during load rejection and emergencies; protection against serious hazards, e.g., loss of oil pressure, high bearing vibration; and testing of valves and vitally important protection functions. It is characteristic of the first group of functions that they must be performed with high control bandwidth, or very high reliability, or both, to ensure long-term satisfactory service of the turbine. It is for these reasons that GE has, from the very beginning of the technology, designed and provided the controls and protection for its units, starting with mechanical and hydraulic devices and progressing to analog electrohydraulic systems introduced in the 1960s, and now continuing with all-digital electrohydraulic systems

Steam up over reactor policy

International Nuclear Information System (INIS)

Kovan, D.

1976-01-01

Britain is once more assessing its nuclear power programme in the light of recent forecasts that there is unlikely to be any growth in the demand for electricity for many years to come. This means that the extra costs of launching a commercially unproven reactor, the Steam Generating Heavy Water Reactor (SGHWR), will be an even greater burden than previously expected, because they would be spread over fewer reactors. Sir John Hill's reported assessment concludes that the present strategy would be the most expensive way of developing Britain's nuclear power programme; and under the circumstances, may not be the best option. The SGHWR programme will certainly be more expensive than either relaunching a programme of advanced gas-cooled reactors (AGRs), or building American designed pressurised water reactors (PWRs). Recent developments of the AGR and PWR's and their advantages in the present position are outlined. (U.K.)

Experimental verification of blade elongation and axial rotor shift in steam turbines

Czech Academy of Sciences Publication Activity Database

Procházka, Pavel

2016-01-01

Roč. 2, č. 3 (2016), s. 190-192 ISSN 2149-8024 Institutional support: RVO:61388998 Keywords : blade elongation * axial rotor shift * steam turbines * magnetoresistive sensors Subject RIV: BI - Acoustics http://www.challengejournal.com/index.php/cjsmec/article/download/74/62

Energy Analysis of Cascade Heating with High Back-Pressure Large-Scale Steam Turbine

Directory of Open Access Journals (Sweden)

Zhihua Ge

2018-01-01

Full Text Available To reduce the exergy loss that is caused by the high-grade extraction steam of traditional heating mode of combined heat and power (CHP generating unit, a high back-pressure cascade heating technology for two jointly constructed large-scale steam turbine power generating units is proposed. The Unit 1 makes full use of the exhaust steam heat from high back-pressure turbine, and the Unit 2 uses the original heating mode of extracting steam condensation, which significantly reduces the flow rate of high-grade extraction steam. The typical 2 × 350 MW supercritical CHP units in northern China were selected as object. The boundary conditions for heating were determined based on the actual climatic conditions and heating demands. A model to analyze the performance of the high back-pressure cascade heating supply units for off-design operating conditions was developed. The load distributions between high back-pressure exhaust steam direct supply and extraction steam heating supply were described under various conditions, based on which, the heating efficiency of the CHP units with the high back-pressure cascade heating system was analyzed. The design heating load and maximum heating supply load were determined as well. The results indicate that the average coal consumption rate during the heating season is 205.46 g/kWh for the design heating load after the retrofit, which is about 51.99 g/kWh lower than that of the traditional heating mode. The coal consumption rate of 199.07 g/kWh can be achieved for the maximum heating load. Significant energy saving and CO2 emission reduction are obtained.

Technology assessment HTR. Part 3. Economics of new concept of the modular High Temperature Reactor

International Nuclear Information System (INIS)

Lako, P.

1996-06-01

In this study the economic feasibility of new concepts of the High Temperature Reactor were investigated. These new concepts are characterized as inherently safe. The different concepts were used as industrial heat/power reactors and compared with a gas fired Steam and Gas turbine installation. The best economic advantages are offered by a HTR with a Thorium/Uranium cycle as compared with a gas fired steam- and gas turbine. 6 figs, 9 tabs, 21 refs

Design and development of gas turbine high temperature reactor 300

International Nuclear Information System (INIS)

Kunitomi, Kazuhiko; Katanishi, Shoji; Takada, Shoji; Yan, Xing; Takizuka, Takakazu

2003-01-01

JAERI (Japan Atomic Energy Research Institute) has been designing a Japan's original gas turbine high temperature reactor, GTHTR300 (Gas Turbine High Temperature Reactor 300). The greatly simplified design based on salient features of the HTGR (High Temperature Gas-cooled reactor) with a closed helium gas turbine enables the GTHTR300 a high efficient and economically competitive reactor to be deployed in early 2010s. Also, the GTHTR300 fully taking advantage of various experiences accumulated in design, construction and operation of the HTTR (High Temperature Engineering Test Reactor) and fossil gas turbine systems reduces technological development concerning a reactor system and electric generation system. Original features of this system are core design with two-year refueling interval, conventional steel material usage for a reactor pressure vessel, innovative plant flow scheme and horizontally installed gas turbine unit. Due to these salient features, the capital cost of the GTHTR300 is less than a target cost of 200 thousands Yen/kWe, and the electric generation cost is close to a target cost of 4 Yen/kWh. This paper describes the original design features focusing on reactor core design, fuel design, in-core structure design and reactor pressure vessel design except PCU design. Also, R and D for developing the power conversion unit is briefly described. The present study is entrusted from the Ministry of Education, Culture, Sports, Science and Technology of Japan. (author)

The influence of selected design and operating parameters on the dynamics of the steam micro-turbine

Science.gov (United States)

Żywica, Grzegorz; Kiciński, Jan

2015-10-01

The topic of the article is the analysis of the influence of selected design parameters and operating conditions on the radial steam micro-turbine, which was adapted to operate with low-boiling agent in the Organic Rankine Cycle (ORC). In the following parts of this article the results of the thermal load analysis, the residual unbalance and the stiffness of bearing supports are discussed. Advanced computational methods and numerical models have been used. Computational analysis showed that the steam micro-turbine is characterized by very good dynamic properties and is resistant to extreme operating conditions. The prototype of micro-turbine has passed a series of test calculations. It has been found that it can be subjected to experimental research in the micro combined heat and power system.

Response to severe changes of load on the reactor system of nuclear ship Mutsu

International Nuclear Information System (INIS)

Ishida, Toshihisa; Kusunoki, Tsuyoshi; Ochiai, Masa-aki; Tanaka, Yoshimi; Yao, Toshiaki; Inoue, Kimio.

1993-01-01

The response of the nuclear power system of N.S. Mutsu to severe changes of load have been studied from records taken during the power-raising tests performed on the ship in 1990. The records examined were those involving the most severe load changes foreseen for marine reactors: (a) sharp load increase with total steam flow raised from 25 to 70 % rated full flow in 13s, (b) crash astern maneuver with the position of propulsion turbine command handle changed-taking several seconds-from cruising ahead to STOP, and after about 50s, further changed-taking 30s-to bring the astern propulsion turbine to full speed-to consume approximately 60 % rated total steam flow and (c) turbine trip with the ahead turbine intentionally tripped when operating at roughly 100 % rated total steam flow. The foregoing records from load changes-of severity beyond what is foreseen for land-based reactors-proved that the Mutsu reactor is capable of responding smoothly and securely to such severe load changes. These load changes occasioned relatively large mismatches between reactor power supply and steam flow demand, but with notable freedom from any conspicuous overshooting or hunting of the reactor power. This performance can be attributed to (a) correct functioning of the automatic power control system, (b) effective contribution of the self-regulating reactor control property deriving from the large negative feedback between moderator temperature and reactivity, and (c) the ample inventories of coolant in the primary and secondary loops. The responses to load change are discussed covering those relevant to (a) reactor power, (b) primary loop pressure, and (c) steam generator pressure, with particular reference to the differences seen in response to mild and to severe load changes. (author)

CFD-based shape optimization of steam turbine blade cascade in transonic two phase flows

International Nuclear Information System (INIS)

Noori Rahim Abadi, S.M.A.; Ahmadpour, A.; Abadi, S.M.N.R.; Meyer, J.P.

2017-01-01

Highlights: • CFD-based shape optimization of a nozzle and a turbine blade regarding nucleating steam flow is performed. • Nucleation rate and droplet radius are the best suited objective functions for the optimization process. • Maximum 34% reduction in entropy generation rate is reported for turbine cascade. • A maximum 10% reduction in Baumann factor and a maximum 2.1% increase in efficiency is achieved for a turbine cascade. - Abstract: In this study CFD-based shape optimization of a 3D nozzle and a 2D turbine blade cascade is undertaken in the presence of non-equilibrium condensation within the considered flow channels. A two-fluid formulation is used for the simulation of unsteady, turbulent, supersonic and compressible flow of wet steam accounting for relevant phase interaction between nucleated liquid droplets and continuous vapor phase. An in-house CFD code is developed to solve the governing equations of the two phase flow and was validated against available experimental data. Optimization is carried out in respect to various objective functions. It is shown that nucleation rate and maximum droplet radius are the best suited target functions for reducing thermodynamic and aerodynamic losses caused by the spontaneous nucleation. The maximum increase of 2.1% in turbine blade efficiency is achieved through shape optimization process.

Design and field operation of 1175 MW steam turbine for Ohi Nuclear Power Station

International Nuclear Information System (INIS)

Hirota, Yoshio; Nakagami, Yasuo; Fujii, Hisashi; Shibanai, Hirooki.

1980-01-01

Two 1175 MW steam turbine and generator units have been successfully in commercial operation since March 1979 and December 1979 respectively at Ohi Nuclear Power Station of the Kansai Electric Power Company. Those units, the largest in their respective outputs in Japan, have also such remarkable design features as two-stage reheat, nozzle governing turbine, water cooled generator stator and turbine-driven feedwater pumps. This paper covers design features and some topics of various pre-operational tests of the above-mentioned units. (author)

Avoiding failures of steam turbine discs by automated ultrasonic inspections

International Nuclear Information System (INIS)

Bird, C.R.; Morton, J.

1994-01-01

Under certain conditions, stress corrosion cracking can cause catastrophic failure of steam turbine discs. Nuclear Electric has developed a range of inspection techniques for disc keyways, bores, buttons and blade attachments and has accumulated substantial experience on their use on plant. This paper gives examples of the techniques used and discusses the strengths and weaknesses of the techniques applied. (Author)

Investigation for vertical, two-phase steam-water flow of three turbine models

International Nuclear Information System (INIS)

Silverman, S.; Goodrich, L.D.

1977-01-01

One of the basic quantities of interest during a loss-of-coolant experiment (LOCE) is the primary system mass flow rate. Presently, there are no transducers commercially available which continuously measure this parameter. Therefore, a transducer was designed at EG and G Idaho, Inc. which combines a drag-disc and turbine into a single unit. The basis for the design was that the drag-disc would measure momentum flux (rhoV 2 ), the turbine would measure velocity and the mass flow rate could then be calculated from the two quantities by assuming a flow profile. For two-phase flow, the outputs are approximately proportional to the desired parameter, but rather large errors can be expected under those assumptions. Preliminary evaluation of the experimental two- and single-phase calibration data has resulted in uncertainty estimates of +-8% of range for the turbine and +-20% of range for the drag-disc. In an effort to reduce the errors, further investigations were made to determine what the drag-disc and turbine really measure. In the present paper, three turbine models for vertical, two-phase, steam/water flow are investigated; the Aya Model, the Rouhani Model, and a volumetric flow model. Theoretical predictions are compared with experimental data for vertical, two-phase steam/water flow. For the purposes of the mass flow calculation, velocity profiles were assumed to be flat for the free-field condition. It is appreciated that this may not be true for all cases investigated, but for an initial inspection, flat profiles were assumed

An optical technique for characterizing the liquid phase of steam at the exhaust of an LP turbine

International Nuclear Information System (INIS)

Kercel, S.W.; Simpson, M.L.; Azar, M.; Young, M.

1993-01-01

Optical observation of velocity and size of water droplets in powerplant steam has several applications. These include the determination of steam wetness fraction, mass flow rate, and predicting erosion of turbine blades and pipe elbows. The major advantages of optical techniques are that they do not interfere with the flow or perturb the observation. This paper describes the measurement of the size and velocity of particles based on the observation and analysis of visibility patterns created by backscattered circularly polarized light. The size of latex particles in a dry nitrogen stream was measured in the laboratory. Visibility patterns of water droplets were observed in the low pressure turbine of Unit 6 of Alabama Power's Gorgas Steam Plant

Pressure tube reactors

International Nuclear Information System (INIS)

Natori, Hisahide.

1981-01-01

Purpose: To improve the electrical power generation efficiency in a pressure tube reactor in which coolants and moderators are separated by feedwater heating with heat generated in heavy water and by decreasing the amount of steams to be extracted from the turbine. Constitution: A heat exchanger and a heavy water cooler are additionally provided to a conventional pressure tube reactor. The heat exchanger is disposed at the pre-stage of a low pressure feedwater heater series. High temperature heavy water heated in the core is passed through the primary side of the exchanger, while feedwater is passed through the secondary side. The cooler is disposed on the downstream of the heat exchanger in the flowing direction of the heavy water, in which heavy water from the heat exchanger is passed through the primary side and the auxiliary equipment cooling water is sent to the secondary side thereof. Accordingly, since extraction of heating steams is no more necessary, the steam can be used for the rotation of the turbine, and the electrical power generation efficiency can be improved. (Seki, T.)

Design study on steam generator integration into the VVER reactor pressure vessel

International Nuclear Information System (INIS)

Hort, J.; Matal, O.

2004-01-01

The primary circuit of VVER (PWR) units is arranged into loops where the heat generated by the reactor is removed by means of main circulating pumps, loop pipelines and steam generators, all located outside the reactor pressure vessel. If the primary circuit and reactor core were integrated into one pressure vessel, as proposed, e.g., within the IRIS project (WEC), a LOCA situation would be limited by the reactor pressure vessel integrity only. The aim of this design study regarding the integration of the steam generator into the reactor pressure vessel was to identify the feasibility limits and some issues. Fuel elements and the reactor pressure vessel as used in the Temelin NPP were considered for the analysis. From among the variants analyzed, the variant with steam generators located above the core and vertically oriented circulating pumps at the RPV lower bottom seems to be very promising for future applications

Nuclear reactor plants and control systems therefor

International Nuclear Information System (INIS)

de Boer, G.A.; de Hex, M.

1976-01-01

A nuclear reactor plant is described comprising at least two hydraulically separated but thermally interconnected heat conveying circuits, of which one is the reactor circuit filled with a non-water medium and the other one is the water-steam-circuit equipped with a steam generator, a feed water conduit controlled by a valve and a steam turbine, and a control system mainly influenced by the pressure drop caused in said feed water conduit and its control valve and having a value of at least 10 bars at full load

Design and field operation of 1175 MW steam turbine for Ohi Nuclear Power Station

International Nuclear Information System (INIS)

Hirota, Y.; Nakagami, Y.; Fujii, H.; Shibanai, H.

1980-01-01

Two 1,175 MW steam turbine and generator units have been successfully in commercial operation since March 1979 and December 1979 respectively at Ohi Nuclear Power Station of the Kansai Electric Power Company. Those units, the largest in their respective outputs in Japan, have also such remarkable design features as two-stage reheat, nozzle governing turbine, water cooled generator stator and turbine-driven feedwater pumps. This paper covers design features and some topics of various pre-operational tests of the above-mentioned units. (author)

Study on thermodynamic cycle of high temperature gas-cooled reactor

International Nuclear Information System (INIS)

Qu Xinhe; Yang Xiaoyong; Wang Jie

2017-01-01

The development trend of the (very) High temperature gas-cooled reactor is to gradually increase the reactor outlet temperature. The different power conversion units are required at the different reactor outlet temperature. In this paper, for the helium turbine direct cycle and the combined cycle of the power conversion unit of the High temperature gas-cooled reactor, the mathematic models are established, and three cycle plans are designed. The helium turbine direct cycle is a Brayton cycle with recuperator, precooler and intercooler. In the combined cycle plan 1, the topping cycle is a simple Brayton cycle without recuperator, precooler and intercooler, and the bottoming cycle is based on the steam parameters (540deg, 6 MPa) recommended by Siemens. In the combined cycle plan 2, the topping cycle also is a simple Brayton cycle, and the bottoming cycle which is a Rankine cycle with reheating cycle is based on the steam parameters of conventional subcritical thermal power generation (540degC, 18 MPa). The optimization results showed that the cycle efficiency of the combined cycle plan 2 is the highest, the second is the helium turbine direct cycle, and the combined cycle plan 2 is the lowest. When the reactor outlet temperature is 900degC and the pressure ratio is 2.02, the cycle efficiency of the combined cycle plan 2 can reach 49.7%. The helium turbine direct cycle has a reactor inlet temperature above 500degC due to the regenerating cycle, so it requires a cooling circuit for the internal wall of the reactor pressure vessel. When the reactor outlet temperature increases, the increase of the pressure ratio required by the helium turbine direct cycle increases may bring some difficulties to the design and manufacture of the magnetic bearings. For the combined cycle, the reactor inlet temperature can be controlled below than 370degC, so the reactor pressure vessel can use SA533 steel without cooling the internal wall of the reactor pressure vessel. The pressure

SINGLE PHASE ANALYTICAL MODELS FOR TERRY TURBINE NOZZLE

Energy Technology Data Exchange (ETDEWEB)

Zhao, Haihua; Zhang, Hongbin; Zou, Ling; O' Brien, James

2016-11-01

All BWR RCIC (Reactor Core Isolation Cooling) systems and PWR AFW (Auxiliary Feed Water) systems use Terry turbine, which is composed of the wheel with turbine buckets and several groups of fixed nozzles and reversing chambers inside the turbine casing. The inlet steam is accelerated through the turbine nozzle and impacts on the wheel buckets, generating work to drive the RCIC pump. As part of the efforts to understand the unexpected “self-regulating” mode of the RCIC systems in Fukushima accidents and extend BWR RCIC and PWR AFW operational range and flexibility, mechanistic models for the Terry turbine, based on Sandia National Laboratories’ original work, has been developed and implemented in the RELAP-7 code to simulate the RCIC system. RELAP-7 is a new reactor system code currently under development with the funding support from U.S. Department of Energy. The RELAP-7 code is a fully implicit code and the preconditioned Jacobian-free Newton-Krylov (JFNK) method is used to solve the discretized nonlinear system. This paper presents a set of analytical models for simulating the flow through the Terry turbine nozzles when inlet fluid is pure steam. The implementation of the models into RELAP-7 will be briefly discussed. In the Sandia model, the turbine bucket inlet velocity is provided according to a reduced-order model, which was obtained from a large number of CFD simulations. In this work, we propose an alternative method, using an under-expanded jet model to obtain the velocity and thermodynamic conditions for the turbine bucket inlet. The models include both adiabatic expansion process inside the nozzle and free expansion process out of the nozzle to reach the ambient pressure. The combined models are able to predict the steam mass flow rate and supersonic velocity to the Terry turbine bucket entrance, which are the necessary input conditions for the Terry Turbine rotor model. The nozzle analytical models were validated with experimental data and

Steam leak detection in advance reactors via acoustics method

International Nuclear Information System (INIS)

Singh, Raj Kumar; Rao, A. Rama

2011-01-01

Highlights: → Steam leak detection system is developed to detect any leak inside the reactor vault. → The technique uses leak noise frequency spectrum for leak detection. → Testing of system and method to locate the leak is also developed and discussed in present paper. - Abstract: Prediction of LOCA (loss of coolant activity) plays very important role in safety of nuclear reactor. Coolant is responsible for heat transfer from fuel bundles. Loss of coolant is an accidental situation which requires immediate shut down of reactor. Fall in system pressure during LOCA is the trip parameter used for initiating automatic reactor shut down. However, in primary heat transport system operating in two phase regimes, detection of small break LOCA is not simple. Due to very slow leak rates, time for the fall of pressure is significantly slow. From reactor safety point of view, it is extremely important to find reliable and effective alternative for detecting slow pressure drop in case of small break LOCA. One such technique is the acoustic signal caused by LOCA in small breaks. In boiling water reactors whose primary heat transport is to be driven by natural circulation, small break LOCA detection is important. For prompt action on post small break LOCA, steam leak detection system is developed to detect any leak inside the reactor vault. The detection technique is reliable and plays a very important role in ensuring safety of the reactor. Methodology developed for steam leak detection is discussed in present paper. The methods to locate the leak is also developed and discussed in present paper which is based on analysis of the signal.

Separated type nuclear superheating reactor

International Nuclear Information System (INIS)

Hida, Kazuki.

1993-01-01

In a separated type nuclear superheating reactor, fuel assemblies used in a reactor core comprise fuel rods made of nuclear fuel materials and moderator rods made of solid moderating materials such as hydrogenated zirconium. Since the moderating rods are fixed or made detachable, high energy neutrons generated from the fuel rods are moderated by the moderating rods to promote fission reaction of the fuel rods. Saturated steams supplied from the BWR type reactor by the fission energy are converted to high temperature superheated steams while passing through a steam channel disposed between the fuel rods and the moderating rods and supplied to a turbine. Since water is not used but solid moderating materials sealed in a cladding tube are used as moderation materials, isolation between superheated steams and water as moderators is not necessary. Further, since leakage of heat is reduced to improve a heat efficiency, the structure of the reactor core is simplified and fuel exchange is facilitated. (N.H.)

Corrosion fatigue in LP steam turbine blading - experiences, causes and appropriate measures; Korrosionsutmattning i aangturbinskovlar - Erfarenheter, inverkande faktorer och moejliga aatgaerder

Energy Technology Data Exchange (ETDEWEB)

Tavast, J [ABB STAL AB, Finspaang (Sweden)

1996-12-01

Corrosion fatigue in LP steam turbine blading was reviewed together with result of tests performed in order to find blade materials with improved resistance against this. According to international experience, corrosion fatigue of 12Cr steam turbine blades in the transition zone between dry and wet steam, is one of the major causes, if not the major cause, for unavailability of steam turbines. Corrosion fatigue in LP blading is a frequent problem also in Swedish and Finnish nuclear power plants, especially in turbines of type D54 in BWR-plants. Corrosion fatigue has also been discovered in at least one type of nuclear turbine. Initiation times have been very long and the varying experiences in different types of turbines may simply reflect differing initiation times. Corrosion fatigue may therefore become more frequent in other types of turbines in the future. The type of water treatment (BWR/PWR) and possibly temperature after reheating seem to influence the risk for corrosion fatigue. Influence of inleakage of cooling water is less clear for these nuclear plants. The long initiation times together with the fact that very few of the cracked blades have actually failed, indicate that the cracks initiate and/or propagate during transients. Extensive laboratory tests show that there are alternative blade materials available with improved resistance against corrosion fatigue, with the most promising being 15/5 PH and A905, together with Ti6Al4V. The Ti alloy shows the best resistance against corrosion fatigue in most environments and is already used in some turbines. Disadvantage is a higher cost and possible need for redesign of the blades. The alternative materials are recommended for use for blades in the transition zone between dry and wet steam in LP turbines. The main disadvantage is a lack of references, even if 15%5 PH has been used to a very limited extent. 40 refs, 24 figs, 12 tabs, 9 appendices

Optimization of Root Section for Ultra-long Steam Turbine Rotor Blade

Czech Academy of Sciences Publication Activity Database

Hála, Jindřich; Luxa, Martin; Šimurda, David; Bobčík, M.; Novák, O.; Rudas, B.; Synáč, J.

2018-01-01

Roč. 27, č. 2 (2018), s. 95-102 ISSN 1003-2169 R&D Projects: GA TA ČR(CZ) TA03020277; GA TA ČR TH02020057 Institutional support: RVO:61388998 Keywords : steam turbine * blade cascade * root section Subject RIV: BK - Fluid Dynamics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 0.678, year: 2016

Mitigation of steam generator tube rupture in a pressurized water reactor with passive safety systems

Science.gov (United States)

McDermott, Daniel J.; Schrader, Kenneth J.; Schulz, Terry L.

1994-01-01

The effects of steam generator tube ruptures in a pressurized water reactor are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger of a passive heat removal system immersed in the in containment refueling water storage tank in response to a high feed water level in the steam generator. Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks at the pressure in the reactor coolant system pressurizer. The high steam generator level is also used to isolate the start-up feed water system and the chemical and volume control system to prevent flooding into the steam header. 2 figures.

Prospects of power conversion technology of direct-cycle helium gas turbine for MHTGR

International Nuclear Information System (INIS)

Li Yong; Zhang Zuoyi

1999-01-01

The modular high temperature gas cooled reactor (MHTGR) is a modern passively safe reactor. The reactor and helium gas turbine may be combined for high efficiency's power conversion, because MHTGR has high outlet temperature up to 950 degree C. Two different schemes are planed separately by USA and South Africa. the helium gas turbine methodologies adopted by them are mainly based on the developed heavy duty industrial and aviation gas turbine technology. The author introduces the differences of two technologies and some design issues in the design and manufacture. Moreover, the author conclude that directly coupling a closed Brayton cycle gas turbine concept to the passively safe MHTGR is the developing direction of MHTGR due to its efficiency which is much higher than that of using steam turbine

Next Generation Engineered Materials for Ultra Supercritical Steam Turbines

Energy Technology Data Exchange (ETDEWEB)

Douglas Arrell

2006-05-31

To reduce the effect of global warming on our climate, the levels of CO{sub 2} emissions should be reduced. One way to do this is to increase the efficiency of electricity production from fossil fuels. This will in turn reduce the amount of CO{sub 2} emissions for a given power output. Using US practice for efficiency calculations, then a move from a typical US plant running at 37% efficiency to a 760 C /38.5 MPa (1400 F/5580 psi) plant running at 48% efficiency would reduce CO2 emissions by 170kg/MW.hr or 25%. This report presents a literature review and roadmap for the materials development required to produce a 760 C (1400 F) / 38.5MPa (5580 psi) steam turbine without use of cooling steam to reduce the material temperature. The report reviews the materials solutions available for operation in components exposed to temperatures in the range of 600 to 760 C, i.e. above the current range of operating conditions for today's turbines. A roadmap of the timescale and approximate cost for carrying out the required development is also included. The nano-structured austenitic alloy CF8C+ was investigated during the program, and the mechanical behavior of this alloy is presented and discussed as an illustration of the potential benefits available from nano-control of the material structure.

The use of tracer techniques to measure water flow rates in steam turbines

International Nuclear Information System (INIS)

Whitfield, O.J.; Blaylock, G.; Gale, R.W.

1979-01-01

Radioactive and chemical tracers offer some unique advantages in detailed flow measurement on steam turbine plant. A series of experiments on a nuclear power station are reported where tracers successfully measured water flow rates and the initial steam moisture with an accuracy suitable for performance and commissioning tests. Both radioactive and chemical tracer methods produced identical results. Straightforward practical procedures were evolved that ensured repeatable accuracy and in addition a quantitative method of detecting heater leaks on load was established. (author)

Gas turbine modular helium reactor in cogeneration

International Nuclear Information System (INIS)

Leon de los Santos, G.

2009-10-01

This work carries out the thermal evaluation from the conversion of nuclear energy to electric power and process heat, through to implement an outline gas turbine modular helium reactor in cogeneration. Modeling and simulating with software Thermo flex of Thermo flow the performance parameters, based on a nuclear power plant constituted by an helium cooled reactor and helium gas turbine with three compression stages, two of inter cooling and one regeneration stage; more four heat recovery process, generating two pressure levels of overheat vapor, a pressure level of saturated vapor and one of hot water, with energetic characteristics to be able to give supply to a very wide gamma of industrial processes. Obtaining a relationship heat electricity of 0.52 and efficiency of net cogeneration of 54.28%, 70.2 MW net electric, 36.6 MW net thermal with 35% of condensed return to 30 C; for a supplied power by reactor of 196.7 MW; and with conditions in advanced gas turbine of 850 C and 7.06 Mpa, assembly in a shaft, inter cooling and heat recovery in cogeneration. (Author)

Accurate calibration of steam turbine speed control system and its influence on primary regulation at electric grid

Energy Technology Data Exchange (ETDEWEB)

Irrazabal Bohorquez, Washington Orlando; Barbosa, Joao Roberto [Technological Institute of Aeronautics (ITA/CTA), Sao Jose dos Campos, SP (Brazil). Center for Reference on Gas Turbine and Energy], E-mail: barbosa@ita.br

2010-07-01

In an interconnected electric system there are two very important parameters: the field voltage and the frequency system. The frequency system is very important for the primary regulation of the electric grid. Each turbomachine actuating as generator interconnected to the grid has an automatic speed regulator to keep the rotational speed and mechanical power of the prime machine operating at the set conditions and stable frequency. The electric grid is a dynamical system and in every moment the power units are exposed to several types of disturbances, which cause unbalance of the mechanical power developed by prime machine and the consumed electric power at the grid. The steam turbine speed control system controls the turbine speed to support the electric grid primary frequency at the same time it controls the frequency of the prime machine. Using a mathematical model for the speed control system, the transfer functions were calculated, as well as the proportionality constants of each element of the steam turbine automatic speed regulator. Among other parameters, the droop characteristic of steam turbine and the dynamic characteristics of the automatic speed regulator elements were calculated. Another important result was the determination of the behavior of the speed control when disturbances occur with the improvement of the calibration precision of the control system. (author)

Strategies for steam

International Nuclear Information System (INIS)

Hennagir, T.

1996-01-01

This article is a review of worldwide developments in the steam turbine and heat recovery steam generator markets. The Far East is driving the market in HRSGs, while China is driving the market in orders placed for steam turbine prime movers. The efforts of several major suppliers are discussed, with brief technical details being provided for several projects

Nuclear reactor types

International Nuclear Information System (INIS)

Jones, P.M.S.

1987-01-01

The characteristics of different reactor types designed to exploit controlled fission reactions are explained. Reactors vary from low power research devices to high power devices especially designed to produce heat, either for direct use or to produce steam to drive turbines to generate electricity or propel ships. A general outline of basic reactors (thermal and fast) is given and then the different designs considered. The first are gas cooled, including the Magnox reactors (a list of UK Magnox stations and reactor performance is given), advanced gas cooled reactors (a list of UK AGRs is given) and the high temperature reactor. Light water cooled reactors (pressurized water [PWR] and boiling water [BWR] reactors) are considered next. Heavy water reactors are explained and listed. The pressurized heavy water reactors (including CANDU type reactors), boiling light water, steam generating heavy water reactors and gas cooled heavy water reactors all come into this category. Fast reactors (liquid metal fast breeder reactors and gas cooled fast reactors) and then water-cooled graphite-moderated reactors (RBMK) (the type at Chernobyl-4) are discussed. (U.K.)

Thermo-economic comparative analysis of gas turbine GT10 integrated with air and steam bottoming cycle

Science.gov (United States)

Czaja, Daniel; Chmielnak, Tadeusz; Lepszy, Sebastian

2014-12-01

A thermodynamic and economic analysis of a GT10 gas turbine integrated with the air bottoming cycle is presented. The results are compared to commercially available combined cycle power plants based on the same gas turbine. The systems under analysis have a better chance of competing with steam bottoming cycle configurations in a small range of the power output capacity. The aim of the calculations is to determine the final cost of electricity generated by the gas turbine air bottoming cycle based on a 25 MW GT10 gas turbine with the exhaust gas mass flow rate of about 80 kg/s. The article shows the results of thermodynamic optimization of the selection of the technological structure of gas turbine air bottoming cycle and of a comparative economic analysis. Quantities are determined that have a decisive impact on the considered units profitability and competitiveness compared to the popular technology based on the steam bottoming cycle. The ultimate quantity that can be compared in the calculations is the cost of 1 MWh of electricity. It should be noted that the systems analyzed herein are power plants where electricity is the only generated product. The performed calculations do not take account of any other (potential) revenues from the sale of energy origin certificates. Keywords: Gas turbine air bottoming cycle, Air bottoming cycle, Gas turbine, GT10

Acceptance test guideline for steam turbine control systems. Anahmerichtlinie fuer Regel- und Steuereinrichtungen von Dampfturbinen

Energy Technology Data Exchange (ETDEWEB)

1983-01-01

The acceptances to be obtained during the first operational run, refer to measures proving the functional integrity of the turbine control system and assuring the compliance with the maximum allowable overspeed in case of lead changes or perturbations. The Guideline concerns essentially speed, power, and pressure controllers coupled to generators. It may be appropriately extended to steam turbines serving other purposes.

Preliminary analysis of combined cycle of modular high-temperature gas cooled reactor

International Nuclear Information System (INIS)

Baogang, Z.; Xiaoyong, Y.; Jie, W.; Gang, Z.; Qian, S.

2015-01-01

Modular high-temperature gas cooled reactor (HTGR) is known as one of the most advanced nuclear reactors because of its inherent safety and high efficiency. The power conversion system of HTGR can be steam turbine based on Rankine cycle or gas turbine based on Brayton cycle respectively. The steam turbine system is mature and the gas turbine system has high efficiency but under development. The Brayton-Rankine combined cycle is an effective way to further promote the efficiency. This paper investigated the performance of combined cycle from the viewpoint of thermodynamics. The effect of non-dimensional parameters on combined cycle’s efficiency, such as temperature ratio, compression ratio, efficiency of compressor, efficiency of turbine, was analyzed. Furthermore, the optimal parameters to achieve highest efficiency was also given by this analysis under engineering constraints. The conclusions could be helpful to the design and development of combined cycle of HTGR. (author)

The impact research of control modes in steam turbine control system (digital electric hydraulic to the low-frequency oscillation of grid

Directory of Open Access Journals (Sweden)

Yanghai Li

2016-01-01

Full Text Available Through the analysis of the control theory for steam turbine, the transfer function of the steam turbine control modes in the parallel operation was obtained. The frequency domain analysis indicated that different control modes of turbine control system have different influence on the damping characteristics of the power system. The comparative analysis shows the direction and the degree of the influence under the different oscillation frequency range. This can provide the theory for the suppression of the low-frequency oscillation from turbine side and has a guiding significance for the stability of power system. The results of simulation tests are consistent with the theoretic analysis.

Emergency systems and protection equipment of modular steam generators for fast reactors

International Nuclear Information System (INIS)

Matal, O.

The requirements are discussed for accident protection of modular steam generators for fast reactors. Accident protection is assessed for a modular through-flow steam generator and for a natural circulation modular steam generator. Benefits and constraints are shown and possible improvements are outlined for accident protection of liquid sodium fired modular steam generators. (Kr)

Reactor feedwater system

International Nuclear Information System (INIS)

Hikabe, Katsumi.

1978-01-01

Purpose: In order to prevent thermal stresses of a core of PWR type reactor, described has been a method for feeding heated recirculating water to the core in the case of the reactor start-up or shut-down. Constitution: A recirculating water is degassed, cleaned up and heated in the steam condensers, and then feeds the water to the reactor, characterized in that heaters are provided in the bypasses of the turbine, so that heated water is constantly supplied to the reactor. (Nakamura, S.)

Outlook for gas turbine plant utilization in htgr power facilities

International Nuclear Information System (INIS)

Beknev, V.S.; Leont'ev, A.I.; Shmidt, K.L.; Surovtsev, I.G.

1983-01-01

The nuclear reactor power plants that have found greatest favor in the nuclear power industry worldwide are pressurized water reactors, boiling-water reactors, and uranium-graphite channel reactors with saturated-steam steam turbine units (PTU). The efficiency of power generating stations built around reactors such as these does not exceed 30 to 32%, and furthermore they are ''tied down'' to water reservoirs, with the entailed severe thermal effects on the environmental surroundings. The low efficiency range cited is evidence of inefficacious utilization of the nuclear fuel, reserves of which have their limits just as there are limits to available reserves of fossil fuels. Forecasts are being floated of a possible uranium crisis (profitable mining of uranium) in the mid-1990's, even with the expected development of breeder reactors to bridge the gap

Coupling of Modular High-Temperature Gas-Cooled Reactor with Supercritical Rankine Cycle

Directory of Open Access Journals (Sweden)

Shutang Zhu

2008-01-01

Full Text Available This paper presents investigations on the possible combination of modular high-temperature gas-cooled reactor (MHTGR technology with the supercritical (SC steam turbine technology and the prospective deployments of the MHTGR SC power plant. Energy conversion efficiency of steam turbine cycle can be improved by increasing the main steam pressure and temperature. Investigations on SC water reactor (SCWR reveal that the development of SCWR power plants still needs further research and development. The MHTGR SC plant coupling the existing technologies of current MHTGR module design with operation experiences of SC FPP will achieve high cycle efficiency in addition to its inherent safety. The standard once-reheat SC steam turbine cycle and the once-reheat steam cycle with life-steam have been studied and corresponding parameters were computed. Efficiencies of thermodynamic processes of MHTGR SC plants were analyzed, while comparisons were made between an MHTGR SC plant and a designed advanced passive PWR - AP1000. It was shown that the net plant efficiency of an MHTGR SC plant can reach 45% or above, 30% higher than that of AP1000 (35% net efficiency. Furthermore, an MHTGR SC plant has higher environmental competitiveness without emission of greenhouse gases and other pollutants.

Detection of steam generator tube leaks in pressurized water reactors

International Nuclear Information System (INIS)

Roach, W.H.

1985-01-01

This report addresses the early detection of small steam generator tube leaks in pressurized water reactors. It discusses the third, and final, year's work on an NRC-funded project examining diagnostic instrumentation in water reactors. The first two years were broad in coverage, concentrating on anticipatory measurements for detection of potential problems in both pressurized- and boiling-water reactors, with recommendations for areas of further study. One of these areas, the early detection of small steam tube leaks in PWRs, formed the basis of study for the last year of the project. Four tasks are addressed in this study of the detection of steam tube leaks. (1) Determination of which physical parameters indicate the onset of steam generator tube leaks. (2) Establishing performance goals for diagnostic instruments which could be used for early detection of steam generator tube leaks. (3) Defining the diagnostic instrumentation and their location which satisfy Items 1 and 2 above. (4) Assessing the need for diagnostic data processing and display. Parameters are identified, performance goals established, and sensor types and locations are specified in the report, with emphasis on the use of existing instrumentation with a minimum of retrofitting. A simple algorithm is developed which yields the leak rate as a function of known or measurable quantities. The conclusion is that leak rates of less than one-tenth gram per second should be detectable with existing instrumentation. (orig./HP)

Application of the combined cycle LWR-gas turbine to PWR for NPP life extension, safety upgrade and improving economy

International Nuclear Information System (INIS)

Kuznetsov, Yu.N.; Gabaraev, B.A.

2002-01-01

Full text: The unconventional technology to extend the lifetime for the NPPs now in operation and make a construction of new NPPs cheaper - erection of steam-gas toppings to the nuclear power units - is considered in the paper. Application of the steam-gas toppings permits through reducing power of ageing reactors to extend lifetime of nuclear power unit, enhance its safety and at the same time to keep full load operation of NPP turbine and other balance-of-plant equipment. Proposed technology is examined for Russian VVER-440 reactor as an example and, also, as a pilot project, for Russian boiling VK-50 reactor now in operation Application of the steam-gas topping permits: extend the service life of ageing VVER-440 reactor by 10...15 years; use the turbine and other NPP balance-of-plant equipment at full power; increase the efficiency of combined cycle up to 48% and more; enhance the safety of NPP operation; utilize NPP balance-of-plant equipment after reactor decommissioning; perform the cost-effective operation in maneuvering modes; increase capacity factor of the plant. The construction of pilot project on the basis of the VK-50 reactor will allow not only to demonstrate new technology but also to attain appreciable economic effect including that obtained due to using the available reserves of the NPP turbine. (author)

Dynamic performances of wet turbine and steam-separator-superheater and their mathematical simulation as objects of temperature control

International Nuclear Information System (INIS)

Golovach, E.A.

1985-01-01

A mathematical model of a turbine and steam-separator-superheater (SSS) as applied to solution of the tasks of steam temperature regulaton after SSS has been developed. SSS as objects of steam temperature control are considerably less inertial, than intermediate superheaters (IS) of power units in thermal power plants, since for typical SSS and IS considered the duration of transition process according to steam temperature after SSS is 5-10 times loweA than for IS

Ways to increase efficiency of the HTGR coupled with the gas-turbine power conversion unit - HTR2008-58274

International Nuclear Information System (INIS)

Golovko, V. F.; Kodochigov, N. G.; Vasyaev, A. V.; Shenoy, A.; Baxi, C. B.

2008-01-01

The paper deals with the issue of increasing efficiency of nuclear power plants with the modular high-temperature helium reactor (HTGR) and direct gas turbine cycle. It should be noted that only this combination can highlight the advantages of the HTGR, namely the ability to heat helium to about 1000 deg. C, in comparison with other reactor plants for electricity generation. The HTGR has never been used in the direct gas turbine cycle. At present, several designs of such commercial plants are at the stage of experimental validation of main technical features. In Russia, 'OKB Mechanical Engineering' together with 'General Atomics' (USA) are developing the GT-MHR project with the reactor power of 600 MW, reactor outlet helium temperature of 850 deg. C, and efficiency of about 45.2%; the South African Republic is developing the PBMR project with the reactor power of 400 MW, reactor outlet helium temperature of 900 deg. C, and efficiency of about 42%; and Japan is developing the GTHTR-300 project with the reactor power of 600 MW, reactor outlet helium temperature of 850 deg. C, and efficiency of about 45.6%. As it has been proven by technical and economic estimations, one of the most important factors for successful promotion of reactor designs is their net efficiency, which must be not lower than 47%. A significant advantage of a reactor plant with the HTGR and gas-turbine power conversion unit over the steam cycle is considerable simplification of the power unit layout and reduction of the required equipment and systems (no steam generators, no turbine hall including steam lines, condenser, deaerator, etc.), which makes the gas-turbine power conversion unit more compact and less costly in production, operation and maintenance. However, in spite of this advantage, it seems that in the projects currently being developed, the potential of the gas-turbine cycle and high-temperature reactor to more efficiently generate electricity is not fully used. For example, in modern

The Steam Generating Heavy Water Reactor

International Nuclear Information System (INIS)

Middleton, J.E.

1975-01-01

An account is given of the SGHWR, the prototype of which was built by the United Kingdom Atomic Energy Authority at Winfrith, under the following headings: Introduction; origin of the SGHWR concept; conceptual design (choice of reactor type, steam cycle, reactor coolant system, nuclear behaviour, fuel design, core design, and protective, auxiliary and containment systems); operation and control (integrity of core cooling, reactivity control, power trimming, long term reactivity control, xenon override, load following, power shaping, spatial stability control, void coefficient); protective systems (breached coolant circuit trip, intact coolant circuits trip, power set-back trip); dynamic characteristics; reactor control; station control (decoupled control system, coupled control system, rate of response); Winfrith prototype (design and safety philosophy, conceptual features and parameters, reactor coolant system, protective systems, emergency core cooling, core structure, fuel design, vented containment). (U.K.)

Possibility of revitalization of control system of steam turbine 210 MW LMZ

International Nuclear Information System (INIS)

Racki, Branko

2004-01-01

It is a one-shaft, three casing condensing turbine, type K-210-130. A rigid coupling connects it directly to the electric energy generator. There is one intermediate superheat of steam and seven non regulated blending for regenerative condensate heating. A considerate number of such turbines have been used on the territory of the Eastern Europe. There are two blocks installed in TP Sisak, Croatia. There is a survey of the existing control system of turbine, power 210 MW. It points out and describes problems appearing during exploitation. Technical solutions according to complexity of realization have been described. It gives an overview of minimum range of modification with utilization of the existing oil system and maximum range by adding separate high pressure oil system with new solutions for performing segments. (Author)

Steam explosion - physical foundations and relation to nuclear reactor safety

International Nuclear Information System (INIS)

Schumann, U.

1982-08-01

'Steam explosion' means the sudden evaporation of a fluid by heat exchange with a hotter material. Other terms are 'vapour explosion', 'thermal explosion', and 'energetic fuel-coolant interaction (FCI)'. In such an event a large fraction of the thermal energy initially stored in the hot material may possibly be converted into mechanical work. For pressurized water reactors one discusses (e.g. in risk analysis studies) a core melt-down accident during which molten fuel comes into contact with water. In the analysis of the consequences one has to investigate steam explosions. In this report an overview over the state of the knowledge is given. The overview is based on an extensive literature review. The objective of the report is to provide the basic knowledge which is required for understanding of the most important theories on the process of steam explosions. Following topics are treated: overview on steam explosion incidents, work potential, spontaneous nucleation, concept of detonation, results of some typical experiments, hydrodynamic fragmentation of drops, bubbles and jets, coarse mixtures, film-boiling, scenario of a core melt-down accident with possible steam-explosion in a pressurized water reactor. (orig.) [de

Frequency and distribution of leakages in steam generators of gas-cooled reactors

International Nuclear Information System (INIS)

Bongratz, R.; Breitbach, G.; Wolters, J.

1988-01-01

In gas cooled reactors with graphitic primary circuit structures - such as HTR, AGR or Magnox - the water ingress is an event of great safety concern. Water or steam entering the primary circuit react with the hot graphite and carbon-oxide and hydrogen are produced. As the most important initiating event a leak in a steam generator must be taken into account. From the safety point of view as well as for availability reasons it is necessary to construct reliable boilers. Thus the occurrence of a boiler leak should be a rare event. In the context of a probabilistic safety study for an HTR-Project much effort was invested to get information about the frequency and the size distribution of tube failures in steam generators of gas cooled reactors. The main data base was the boiler tube failure statistics of United Kingdom gas cooled reactors. The data were selected and applied to a modern HTR steam generator design. A review of the data showed that the failure frequency is not connected with the load level (pressures, temperatures) or with the geometric size of the heating surface of the boiler. Design, construction, fabrication, examination and operation conditions have the greatest influence an the failure frequency but they are practically not to be quantified. The typical leak develops from smallest size. By erosion effects of the entering water or steam it is enlarged to perhaps some mm 2 , then usually it is detected by moisture monitors. Sudden tube breaks were not reported in the investigated period. As a rule boiler leaks in gas cooled reactors are much more, rare then leaks in steam generators of light water reactors and fossil fired boilers. (author)

Ecotaxes and their impact in the cost of steam and electric energy generated by a steam turbine system

International Nuclear Information System (INIS)

Montero, Gisela

2006-01-01

Ecotaxes allow the internalization of costs that are considered externalities associated with polluting industrial process emissions to the atmosphere. In this paper, ecotaxes internalize polluting emissions negative impacts that are added to electricity and steam generated costs of a steam turbine and heat recovery systems from a utilities refinery plant. Steam costs were calculated by means of an exergy analysis tool and Aspen Plus simulation models. Ecotaxes were calculated for specific substances emitted in the refinery flue gases, based on a toxicity and pollution scale. Ecotaxes were generated from a model that includes damages produced to biotic and abiotic resources and considers the relative position of those substances in a toxicity and pollution scale. These ecotaxes were internalized by an exergoeconomic analysis resulting in an increase in the cost per kWh produced. This kind of ecotax is not applied in Mexico. The values of ecotaxes used in the cost determination are referred to the values currently applied by some European countries to nitrogen oxides emissions. (author)

Computer-aided ultrasonic inspection of steam turbine rotors

Energy Technology Data Exchange (ETDEWEB)

Mayer, K H; Weber, M; Weiss, M [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

1999-12-31

As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

Computer-aided ultrasonic inspection of steam turbine rotors

Energy Technology Data Exchange (ETDEWEB)

Mayer, K.H.; Weber, M.; Weiss, M. [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

1998-12-31

As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

Evaluation of a sodium-water reaction event caused by steam generator tubes break in the prototype generation IV sodium-cooled fast reactor

Energy Technology Data Exchange (ETDEWEB)

Ahn, Sang June; Ha, Kwi Seok; Chang, Won Pyo; Kang, Seok Hun; Lee, Kwi Lim; Choi, Chi Woong; Lee, Seung Won; Yoo, Jin; Jeong, Jae Ho; Jeong, Tae Kyeong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-08-15

The prototype generation IV sodium-cooled fast reactor (PGSFR) has been developed by the Korea Atomic Energy Research Institute. This reactor uses sodium as a reactor coolant to transfer the core heat energy to the turbine. Sodium has chemical characteristics that allow it to violently react with materials such as a water or steam. When a sodium–water reaction (SWR) occurs due to leakage or breakage of steam generator tubes, high-pressure waves and corrosive reaction products are produced, which threaten the structural integrity of the components of the intermediate heat-transfer system (IHTS) and the safety of the primary heat-transfer system (PHTS). In the PGSFR, SWR events are included in the design-basis event. This event should be analyzed from the viewpoint of the integrities of the IHTS and fuel rods. To evaluate the integrity of the IHTS based on the consequences of the SWR, the behaviors of the generated high-pressure waves are analyzed at the major positions of a failed IHTS loop using a sodium–water advanced analysis method-II code. The integrity of the fuel rods must be consistently maintained below the safety acceptance criteria to avoid the consequences of the SWR. The integrity of the PHTS is evaluated using the multidimensional analysis of reactor safety-liquid metal reactor code to model the whole plant.

Evaluation of a Sodium–Water Reaction Event Caused by Steam Generator Tubes Break in the Prototype Generation IV Sodium-cooled Fast Reactor

Directory of Open Access Journals (Sweden)

Sang June Ahn

2016-08-01

Full Text Available The prototype generation IV sodium-cooled fast reactor (PGSFR has been developed by the Korea Atomic Energy Research Institute. This reactor uses sodium as a reactor coolant to transfer the core heat energy to the turbine. Sodium has chemical characteristics that allow it to violently react with materials such as a water or steam. When a sodium–water reaction (SWR occurs due to leakage or breakage of steam generator tubes, high-pressure waves and corrosive reaction products are produced, which threaten the structural integrity of the components of the intermediate heat-transfer system (IHTS and the safety of the primary heat-transfer system (PHTS. In the PGSFR, SWR events are included in the design-basis event. This event should be analyzed from the viewpoint of the integrities of the IHTS and fuel rods. To evaluate the integrity of the IHTS based on the consequences of the SWR, the behaviors of the generated high-pressure waves are analyzed at the major positions of a failed IHTS loop using a sodium–water advanced analysis method-II code. The integrity of the fuel rods must be consistently maintained below the safety acceptance criteria to avoid the consequences of the SWR. The integrity of the PHTS is evaluated using the multidimensional analysis of reactor safety-liquid metal reactor code to model the whole plant.

Arabelle: The most powerful steam turbine in the world

International Nuclear Information System (INIS)

Lamarque, F.; Deloroix, V.

1998-01-01

On the 30th of August 1996 at the CHOOZ power station in the Ardennes, the first 1,500 MW turbine was started up under nuclear steam and connected to the grid. It will reach full power in the spring of 1997, followed shortly afterwards by a second identical machine. This turbine, known as ARABELLE, is currently the most powerful in the world, with a single line rotating at 1,500 rpm. It has been entirely designed, manufactured and installed by the teams of GEC ALSTHOM, within the framework of the Electricite de France N4 PWR program. It represents a new type of nuclear turbine, the fruit of much research and development work which started in the 1980s. It benefits from GEC ALSTHOM's considerable experience in the field of nuclear turbines: 143 machines with a total power output of 100,000 MW and more than ten million hours of operation. It should be remembered that the first 1,000 MW unit for a PWR plant was connected at Fessenheim in 1977, and since then the different EDF plants have been equipped with 58 GEC ALSTHOM turbines, ranging from 1,000 MW to 1,350 MW, this providing the company with a vast amount of information. The process which led to a new design for ARABELLE was based on: Feedback of service experience from previous machines; this provides precious learning material with a view to improving the performance of operating equipment. Research and development work resulting in significant technical advances which could then be integrated into the design of a new generation of turbines. Taking account of the major concerns of the customer-user: Electricite de France (EDF): Improved reliability and operating availability, increased efficiency, reduced investment and maintenance costs

An investigation of nucleating flows of steam in a cascade of turbine blading: Effect of overall pressure ratios

International Nuclear Information System (INIS)

Bakhtar, F.; Savage, R.A.

1993-01-01

In the course of expansion of steam in turbines the state path crosses the saturation line and the fluid becomes a two-phase mixture. To reproduce turbine nucleating and wet conditions realistically requires a supply of supercooled steam which can be obtained under blow down conditions. An experimental short duration cascade tunnel working on this principle has been constructed. The blade profile studied is that of a typical nozzle The paper is one of a set and describes the surface pressure measurements carried out to investigate the effect of the overall pressure ratio on the performance of the blade

Linear Dynamics Model for Steam Cooled Fast Power Reactors

Energy Technology Data Exchange (ETDEWEB)

Vollmer, H

1968-04-15

A linear analytical dynamic model is developed for steam cooled fast power reactors. All main components of such a plant are investigated on a general though relatively simple basis. The model is distributed in those parts concerning the core but lumped as to the external plant components. Coolant is considered as compressible and treated by the actual steam law. Combined use of analogue and digital computer seems most attractive.

An innovative modular device and wireless control system enabling thermal and pressure sensors using FPGA on real-time fault diagnostics of steam turbine functional deterioration

Science.gov (United States)

Devi, S.; Saravanan, M.

2018-03-01

It is necessary that the condition of the steam turbines is continuously monitored on a scheduled basis for the safe operation of the steam turbines. The review showed that steam turbine fault detection and operation maintenance system (STFDOMS) is gaining importance recently. In this paper, novel hardware architecture is proposed for STFDOMS that can be communicated through the GSM network. Arduino is interfaced with the FPGA so as to transfer the message. The design has been simulated using the Verilog programming language and implemented in hardware using FPGA. The proposed system is shown to be a simple, cost effective and flexible and thereby making it suitable for the maintenance of steam turbines. This system forewarns the experts to access to data messages and take necessary action in a short period with great accuracy. The hardware developed is promised as a real-time test bench, specifically for investigations of long haul effects with different parameter settings.

Gas reactor international cooperative program interim report: German Pebble Bed Reactor design and technology review

International Nuclear Information System (INIS)

1978-09-01

This report describes and evaluates several gas-cooled reactor plant concepts under development within the Federal Republic of Germany (FRG). The concepts, based upon the use of a proven Pebble Bed Reactor (PBR) fuel element design, include nuclear heat generation for chemical processes and electrical power generation. Processes under consideration for the nuclear process heat plant (PNP) include hydrogasification of coal, steam gasification of coal, combined process, and long-distance chemical heat transportation. The electric plant emphasized in the report is the steam turbine cycle (HTR-K), although the gas turbine cycle (HHT) is also discussed. The study is a detailed description and evaluation of the nuclear portion of the various plants. The general conclusions are that the PBR technology is sound and that the HTR-K and PNP plant concepts appear to be achievable through appropriate continuing development programs, most of which are either under way or planned

Investigation of thermodynamic cycle for generic 1200 MW{sub el} pressure channel reactor with nuclear steam superheat

Energy Technology Data Exchange (ETDEWEB)

Vincze, A.; Sidawi, K.; Abdullah, R.; Baldock, M.; Saltanov, E.; Pioro, I., E-mail: andrei.vincze@uoit.net, E-mail: khalil.sidawi@uoit.net, E-mail: rand.abdullah@uoit.net, E-mail: matthew.baldock@uoit.net, E-mail: eugene.saltanov@uoit.ca, E-mail: igor.pioro@uoit.ca [Univ. of Ontario Inst. of Tech., Oshawa, ON (Canada)

2014-07-01

Current Nuclear Power Plants (NPPs) play a significant role in energy production around the world. All NPPs operating today employ a Rankine steam cycle for the conversion of thermal power to electricity. This paper will examine the steam cycle arrangement an experimental pressure channel reactor using Nuclear Steam Superheat (NSS) and compare it to two advanced reactor designs, the Advanced CANDU Reactor 1000 (ACR-1000) and the Advanced Boiling Water Reactor (ABWR) designs. The thermodynamic cycle layout and thermal efficiencies of the three reactor types will be discussed. (author)

Prevention device for rapid reactor core shutdown in BWR type reactors

International Nuclear Information System (INIS)

Koshi, Yuji; Karatsu, Hiroyuki.

1986-01-01

Purpose: To surely prevent rapid shutdown of a nuclear reactor upon partial load interruption due to rapid increase in the system frequency. Constitution: If a partial load interruption greater than the sum of the turbine by-pass valve capacity and the load setting bias portion is applied in a BWR type power plant, the amount of main steams issued from the reactor is decreased, the thermal input/output balance of the reactor is lost, the reactor pressure is increased, the void is collapsed, the neutron fluxes are increased and the reactor power rises to generate rapid reactor shutdown. In view of the above, the turbine speed signal is compared with a speed setting value in a recycling flowrate control device and the recycling pump is controlled to decrease the recycling flowrate in order to compensate the increase in the neutron fluxes accompanying the reactor power up. In this way, transient changes in the reactor core pressure and the neutron fluxes are kept within a setting point for the rapid reactor shutdown operation thereby enabling to continue the plant operation. (Horiuchi, T.)

Influence of prolonged service of steam turbines on the properties of materials of rotor and vessel components

International Nuclear Information System (INIS)

Anfimov, V.M.; Artamonov, V.V.; Chizhik, T.A.

1984-01-01

The structure and mechanical properties of steam turbine elements of 25Kh1MF, 25Kh1M1FA (rotors), 15Kh1M1FL (vessel components) steels have been investigated both in initial state and after 200 000 h operation. The structure stability and phase composition of rotor steels providing conservation of heat resistance at a required level was established. Examination of vessel components showed a decrease in the yield strength by 15-20% and durability - by 10% as compared to initial ones. The conclusion on a possible prolongation of the steam turbine service life to 200 000 h is drawn. The nominal service life equals 100 000 h

Air water loop - an experimental facility to study thermal hydraulics of AHWR steam drum

International Nuclear Information System (INIS)

Bagul, R.K.; Pilkhwal, D.S.; Jain, V.; Vijayan, P.K.

2014-05-01

In the proposed Indian Advanced Heavy Water Reactor (AHWR) the coolant recirculation in the primary system is achieved by two-phase natural circulation. The two-phase steam-water mixture from the reactor core is separated in steam drum by gravity. Gravity separation of phases may lead to undesirable phenomena - carryover and carryunder. Carryover is the entrainment of liquid droplets in the vapor phase.Carryover needs to be minimized to avoid erosion corrosion of turbine blades. Carryunder is the entrainment of vapor bubbles with liquid flowing back to reactor core. Significant carryunder may in turn lead to reduced flow resulting in reduced CHF margin and stability in the coolant channel. An Air-Water Loop (AWL) has been designed to carry out the experiments relevant to AHWR steam drum. The design features and scaling philosophy is described in this report. (author)

Assessment and status report High-Temperature Gas-Cooled Reactor gas-turbine technology

International Nuclear Information System (INIS)

1981-01-01

Purpose of this report is to present a brief summary assessment of the High Temperature Gas-Cooled Reactor - Gas Turbine (HTGR-GT) technology. The focal point for the study was a potential 2000 MW(t)/800 MW(e) HTGR-GT commercial plant. Principal findings of the study were that: the HTGR-GT is feasible, but with significantly greater development risk than the HTGR-SC (Steam Cycle). At the level of performance corresponding to the reference design, no incremental economic incentive can be identified for the HTGR-GT to offset the increased development costs and risk relative to the HTGR-SC. The relative economics of the HTGR-GT and HTGR-SC are not significantly impacted by dry cooling considerations. While reduced cycel complexity may ultimately result in a reliability advantage for the HTGR-GT, the value of that potential advantage was not quantified

Materials for Advanced Ultrasupercritical Steam Turbines Task 4: Cast Superalloy Development

Energy Technology Data Exchange (ETDEWEB)

Thangirala, Mani

2015-09-30

The Steam Turbine critical stationary structural components are high integrity Large Shell and Valve Casing heavy section Castings, containing high temperature steam under high pressures. Hence to support the development of advanced materials technology for use in an AUSC steam turbine capable of operating with steam conditions of 760°C (1400°F) and 35 Mpa (5000 psia), Casting alloy selection and evaluation of mechanical, metallurgical properties and castability with robust manufacturing methods are mandated. Alloy down select from Phase 1 based on producability criteria and creep rupture properties tested by NETL-Albany and ORNL directed the consortium to investigate cast properties of Haynes 282 and Haynes 263. The goals of Task 4 in Phase 2 are to understand a broader range of mechanical properties, the impact of manufacturing variables on those properties. Scale up the size of heats to production levels to facilitate the understanding of the impact of heat and component weight, on metallurgical and mechanical behavior. GE Power & Water Materials and Processes Engineering for the Phase 2, Task 4.0 Castings work, systematically designed and executed casting material property evaluation, multiple test programs. Starting from 15 lbs. cylinder castings to world’s first 17,000 lbs. poured weight, heavy section large steam turbine partial valve Haynes 282 super alloy casting. This has demonstrated scalability of the material for steam Turbine applications. Activities under Task 4.0, Investigated and characterized various mechanical properties of Cast Haynes 282 and Cast Nimonic 263. The development stages involved were: 1) Small Cast Evaluation: 4 inch diam. Haynes 282 and Nimonic 263 Cylinders. This provided effects of liquidus super heat range and first baseline mechanical data on cast versions of conventional vacuum re-melted and forged Ni based super alloys. 2) Step block castings of 300 lbs. and 600 lbs. Haynes 282 from 2 foundry heats were evaluated which

Pressurized-water coolant nuclear reactor steam generator

International Nuclear Information System (INIS)

Mayer, H.; Schroder, H.J.

1975-01-01

A description is given of a pressurized-water coolant nuclear reactor steam generator having a vertical housing for the steam generating water and containing an upstanding heat exchanger to which the pressurized-water coolant passes and which is radially surrounded by a guide jacket supporting a water separator on its top. By thermosiphon action the steam generating water flows upward through and around the heat exchanger within the guide chamber to the latter's top from which it flows radially outwardly and downwardly through a down draft space formed between the outside of the jacket and the housing. The water separator discharges separated water downwardly. The housing has a feedwater inlet opening adjacent to the lower portion of the heat exchanger, providing preheating of the introduced feedwater. This preheated feedwater is conveyed by a duct upwardly to a location where it mixes with the water discharged from the water separator

Condensation of steam

International Nuclear Information System (INIS)

Prisyazhniuk, V.A.

2002-01-01

An equation for nucleation kinetics in steam condensation has been derived, the equation taking into account the concurrent and independent functioning of two nucleation mechanisms: the homogeneous one and the heterogeneous one. The equation is a most general-purpose one and includes all the previously known condensation models as special cases. It is shown how the equation can be used in analyzing the process of steam condensation in the condenser of an industrial steam-turbine plant, and in working out new ways of raising the efficiency of the condenser, as well as of the steam-turbine plant as a whole. (orig.)

Screening reactor steam/water piping systems for water hammer

International Nuclear Information System (INIS)

Griffith, P.

1997-09-01

A steam/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam bubble collapse induced water hammer, six conditions must be met in order for one to occur. These are: (1) the pipe must be almost horizontal; (2) the subcooling must be greater than 20 C; (3) the L/D must be greater than 24; (4) the velocity must be low enough so that the pipe does not run full, i.e., the Froude number must be less than one; (5) there should be void nearby; (6) the pressure must be high enough so that significant damage occurs, that is the pressure should be above 10 atmospheres. Recommendations on how to avoid this kind of water hammer in both the design and the operation of the reactor system are made

Hydrogen production by biomass steam gasification in fluidized bed reactor with Co catalyst

International Nuclear Information System (INIS)

Kazuhiko Tasaka; Atsushi Tsutsumi; Takeshi Furusawa

2006-01-01

The catalytic performances of Co/MgO catalysts were investigated in steam gasification of cellulose and steam reforming of tar derived from cellulose gasification. For steam reforming of cellulose tar in a secondary fixed bed reactor, 12 wt.% Co/MgO catalyst attained more than 80% of tar reduction. The amount of produced H 2 and CO 2 increased with the presence of catalyst, and kept same level during 2 hr at 873 K. It is indicated that steam reforming of cellulose tar proceeds sufficiently over Co/MgO catalyst. For steam gasification of cellulose in a fluidized bed reactor, it was found that tar reduction increases with Co loading amount and 36 wt.% Co/MgO catalyst showed 84% of tar reduction. The amounts of produced gas kept for 2 hr indicating that 36 wt.% Co/MgO catalyst is stable during the reaction. It was concluded that these Co catalysts are promising systems for the steam gasification of cellulose and steam reforming of cellulose tar. (authors)

Studying the processes of sodium-water interaction in the BOR-60 reactor micromodule steam generator

International Nuclear Information System (INIS)

Tsykanov, V.A.; Antipin, G.K.; Borisov, V.V.

1981-01-01

Main results of experimental studies of emergency regimes of micromodule steam generator (MSG) at small and big leaks of water into sodium, realized using the 30 MW MSG, operating in the BOR-o0 reactor, are considered. The aims of the study are as follows: the modelling of macroleak in ''Nadja'' steam generator for the BN-350 reactor; testing the conceptions of alarm signalling and MSG protection; testing under real conditions of new perspective systems of leak detection; gaining the experimence and development of the ways to eliminate the consequences of accident caused by big water leak into sodium; accumulation of knowledge on restoration of MSG operating ability after accident; experimental test of calculational techniques for big leak accidents to use them in future for calculational studies of similar situations at other reactors equipped with sodium-water steam generators; refinement of characteristics of hydrodynamic and thermal effects interaction zone for big leak in real circuit during the plant operation. A series of experiments with the imitation of water leak into sodium by means of argon and steam supply through injection devices, located before the steam superheater module of one of the sections and between evaporator module of the same section, is conducted. The range of steam flow rate is 0.02-0.45 g/s. Duration of steam supply is 100-400 s. A conclusion is made that the results obtained can be used for steam generator of the BN-350 reactor [ru

IAEA Technical Meeting on Innovative Heat Exchanger and Steam Generator Designs for Fast Reactors. Working Material

International Nuclear Information System (INIS)

2011-01-01

The IAEA, within the framework of its Nuclear Energy Department’s Technical Working Group on Fast Reactors (TWG-FR), assists Member States activities in fast reactors technology development areas by providing an umbrella for information exchange [topical Technical Meetings (TMs), Workshops and large Conferences] and collaborative R&D [Coordinated Research Projects (CRPs)]. The Technical meeting on “Innovative Heat Exchanger and Steam Generator Designs for Fast Reactors” was held from 21 – 22 December 2011 in Vienna, addressing Member States’ expressed needs of information exchange in the field of advanced fast reactor design features, with particular attention to innovative heat exchangers and steam generators. The Objective of the TM is to provide a global forum for in-depth information exchange and discussion on the most advanced concepts of heat exchangers and steam generators for fast reactors. More specifically, the objectives are: · Review of the status of advanced fast reactor development activities with special emphasis on design and performance of heat exchangers and steam generators; · Discuss requirements for innovative heat exchangers and steam generators; · Present results of studies and conceptual designs for innovative heat exchangers and steam generators; · Provide recommendations for international collaboration under the IAEA aegis. The meeting agenda of the meeting is in Annex I

Power Plants, Steam and Gas Turbines WebQuest

Directory of Open Access Journals (Sweden)

Carlos Ulloa

2012-10-01

Full Text Available A WebQuest is an Internet-based and inquiry-oriented learning activity. The aim of this work is to outline the creation of a WebQuest entitled “Power Generation Plants: Steam and Gas Turbines.” This is one of the topics covered in the course “Thermodynamics and Heat Transfer,” which is offered in the second year of Mechanical Engineering at the Defense University Center at the Naval Academy in Vigo, Spain. While participating in the activity, students will be divided into groups of no more than 10 for seminars. The groups will create PowerPoint presentations that include all of the analyzed aspects. The topics to be discussed during the workshop on power plant turbines are the: (1 principles of operation; (2 processes involved; (3 advantages and disadvantages; (4 efficiency; (5 combined cycle; and (6 transversal competences, such as teamwork, oral and written presentations, and analysis and synthesis of information. This paper presents the use of Google Sites as a guide to the WebQuest so that students can access all information online, including instructions, summaries, resources, and information on qualifications.

HTGR steam generator development

International Nuclear Information System (INIS)

Schuetzenduebel, W.G.; Hunt, P.S.; Weber, M.

1976-01-01

More than 40 gas-cooled reactor plants have produced in excess of 400 reactor years of operating experience which have proved a reasonably high rate of gas-cooled reactor steam generator availability. The steam generators used in these reactors include single U-tube and straight-tube steam generators as well as meander type and helically wound or involute tube steam generators. It appears that modern reactors are being equipped with helically wound steam generators of the once-through type as the end product of steam generator evolution in gas-cooled reactor plants. This paper provides a general overview of gas-cooled reactor steam generator evolution and operating experience and shows how design criteria and constraints, research and development, and experience data are factored into the design/development of modern helically wound tube steam generators for the present generation of gas-cooled reactors

Evaluation of materials' corrosion and chemistry issues for advanced gas cooled reactor steam generators using full scale plant simulations

International Nuclear Information System (INIS)

Woolsey, I.S.; Rudge, A.J.; Vincent, D.J.

1998-01-01

Advanced Gas Cooled Reactors (AGRS) employ once-through steam Generators of unique design to provide steam at approximately 530 degrees C and 155 bar to steam turbines of similar design to those of fossil plants. The steam generators are highly compact, and have either a serpentine or helical tube geometry. The tubes are heated on the outside by hot C0 2 gas, and steam is generated on the inside of the tubes. Each individual steam generator tube consists of a carbon steel feed and primary economiser section, a 9%Cr steel secondary economiser, evaporator and primary superheater, and a Type 316L austenitic stainless steel secondary superheater, all within a single tube pass. The multi-material nature of the individual tube passes, the need to maintain specific thermohydraulic conditions within the different material sections, and the difficulties of steam generator inspection and repair, have required extensive corrosion-chemistry test programmes to ensure waterside corrosion does not present a challenge to their integrity. A major part of these programmes has been the use of a full scale steam generator test facility capable of simulating all aspects of the waterside conditions which exist in the plant. This facility has been used to address a wide variety of possible plant drainage/degradation processes. These include; single- and two-phase flow accelerated corrosion of carbon steel, superheat margins requirements and the stress-corrosion behaviour of the austenitic superheaters, on-load corrosion of the evaporator materials, and iron transport and oxide deposition behaviour. The paper outlines a number of these, and indicates how they have been of value in helping to maintain reliable operation of the plant. (author)

Co-generation on steam industrial systems with disks turbines; Co-geracao em sistemas industriais de vapor com turbinas de discos

Energy Technology Data Exchange (ETDEWEB)

Lezsovits, Ferenc [Universidad de Tecnologia y Economia de Budapest (Hungary)

2010-03-15

The disk turbine, also called Tesla turbine, being of simple construction and low cost, can be used as steam pressure reduction on industrial systems, generating simultaneously electric power, becoming the co-generation even at lower levels. Can be used for various operational parameters and mass flux ratios.This paper analyses the advantages and disadvantages of the turbines under various operation conditions.

Fast-Valving of Large Steam Turbine Units as a Means of Power System Security Enhancement

Directory of Open Access Journals (Sweden)

Bogdan Sobczak

2014-03-01

Full Text Available Fast-valving assists in maintaining system stability following a severe transmission system fault by reducing the turbine mechanical power. Fast-valving consists in rapid closing and opening of steam valves in an adequate manner to reduce the generator accelerating power following the recognition of a severe fault. FV can be an effective and economical method of meeting the performance requirements of a power system in the presence of an increase in wind and solar generation in the power system, newly connected large thermal units and delaying of building new transmission lines. The principle of fast-valving and advantages of applying this technique in large steam turbine units was presented in the paper. Effectiveness of fast-valving in enhancing the stability of the Polish Power Grid was analyzed. The feasibility study of fast-valving application in the 560 MW unit in Kozienice Power Station (EW SA was discussed.

Mathematical modeling of a fast-breeder-reactor generating unit

International Nuclear Information System (INIS)

Kim, V.E.; Golovach, E.A.; Senkin, V.I.

1984-01-01

Dynamics equations are given for a reactor, intermediate heat exchanger, steam generator, and turbogenerator. The dynamic characteristics of the generating unit are described when perturbations occur in grid frequency, turbine valves, and feedwater consumption

Analysis of fast reactor steam generator performance

International Nuclear Information System (INIS)

Hulme, G.; Curzon, A.F.

1992-01-01

A computer model for the prediction of flow and temperature fields within a fast reactor steam generator unit is described. The model combines a commercially available computational fluid dynamics (CFD) solver (PHOENICS) with a steam-tube calculation and provides solutions for the fully coupled flow and temperature fields on both the shell side and the tube side. The model includes the inlet and outlet headers and the bottom end stagnant zone. It also accounts for the effects of support grids and edge-gaps. Two and three dimensional and transient calculations have been performed for both straight tube and J-tube units. Examples of the application of the model are presented. (7 figures) (Author)

Redesign of steam turbine rotor blades and rotor packages – Environmental analysis within systematic eco-design approach

International Nuclear Information System (INIS)

Baran, Jolanta

2016-01-01

Highlights: • Systematic approach to eco-design of steam turbine rotor blades was applied. • Eco-innovative solutions are based on structural and technological change. • At the stage of detailed design the variants were analyzed using LCA. • Main achieved benefits: energy and material savings, lower environmental impact. • Benefits related to the possible scale of the solution practical application. - Abstract: Eco-design of steam turbine blades could be one of the possibilities of decreasing the environmental impact of energy systems based on turbines. The paper investigates the eco-design approach to elaboration of the rotor blades and packages. The purpose is to present the course of eco-design of the rotor blades and the rotor packages taking account of eco-design assumptions, solutions and the concept itself. The following eco-design variants of the rotor blades and the rotor packages are considered: elements of the rotor blades made separately (baseline variant of the rotor blades); elements of the rotor blades made of one piece of material; blades in packages made separately and welded (baseline variant of the rotor packages); packages milled as integral elements. At the stage of detailed design, the Life Cycle Assessment (LCA) is performed in relation to a functional unit – the rotor blades and packages ready for installation in a steam turbine, which is the stage of the turbine. The obtained results indicate that eco-innovative solutions for the turbine blades and packages could be achieved through structural and technological changes. Applying new solutions of the rotor blades may produce the following main benefits: 3.3% lower use of materials, 29.4% decrease in energy consumption at the manufacturing stage, 7.7% decrease in the environmental impact in the life cycle. In relation to the rotor packages, the following main benefits may be achieved: 20.5% lower use of materials, 25.0% decrease in energy consumption at the production stage, 16

Influence of the Operational Wear of the Stator Parts of Shroud Seals on the Economic Efficiency of the Steam Turbines

Science.gov (United States)

Kostyuk, A. G.; Dmitriev, S. S.; Petrunin, B. N.; Gusev, A. A.

2018-01-01

During the operation of steam turbines under transient conditions, due to different thermal expansion of the stator and rotor parts in the radial and axial directions, the clearances fixed in the course of assembling the seals of the flow path change, which causes rubbing in the seals and the wear of the latter. This inevitably increases the leakages through the seals. A particularly large difference in the relative axial and radial displacements of the rotor and stator parts is observed during the turbine start-ups when the difference in their temperature expansion is maximal. Upon the turbine stops, the turbine shafting runs down freely, as a rule, passing through all critical speeds at which the amplitude of the shafting oscillations reach their peak values, which also leads to seizures in the seals and their wear and tear. The seizures in the seals may also be a consequence of the eccentricity between the rotor and stator caused by the thermal strain of the stator, incorrect choice of the clearances, floating-up of the rotor in the bearing, and many other factors. Recently, standard shroud labyrinth seals are being replaced in the steam turbines by seals with honeycomb stator inserts, the design of which allows the ridges to cut into the honeycomb surface without damaging the former, which allows fixing a radial clearance in the seals of 0.5 mm. On the honeycomb surface where the ridges touch it, grooves are cut through. The wear of the shroud seals reduces the efficiency of the steam turbines during the operation to the greatest degree. However, by the present there have been no exact quantitative data available on the change in the leakage through the worn-out honeycomb seals. The paper presents the results of comparative experimental studies on the flow and power characteristics of seal models with smooth and honeycomb stator parts for various degrees of their wear. The studies showed that the leakages through the worn-out stator parts of the honeycomb seals

Physical-chemistry aspects of water in steam turbines associated with material stress and electrochemical assessment of the AISI 403 to simulate real condition

Energy Technology Data Exchange (ETDEWEB)

Pacheco, D S; Franco, C V; Godinho, J F; Frech, W A; Sonai, G G [Univ. Federal de Santa Catarina, Florianopolis (Brazil); Torres, L A.M.; Ellwanger, A R.F. [Tractebel Energia, Capivari de Baixo (Brazil)

2009-07-01

This study described a methodology developed to prevent the occurrence of corrosion failure in steam turbines. The methodology was developed after the failure of a turbine blade at a plant in Brazil. Deposits were collected from various locations along the turbine blade path and analyzed. A turbine deposit collector and simulator was installed to determine the concentrations of steam impurities. Samples were collected from the low pressure turbine at the crossover point and from the polishing station and analyzed using inductive coupled plasma-mass spectrometry (ICP-MS) in order to determine if sodium levels exceeded 3 ppb. Filters were weighed in order to determine the accumulation of impurities. A 3-electrode system was used to determine the influence of chloride ions. The design of the system's condensate polisher beds was modified in order to improve condensate effluent conductivity. The condensate treatment procedure lowered the concentrations of salt impurities and established a monitoring methodology for water and steam used at the plant. It was concluded that the methodology can be used to to reduce inspection intervals and increase system reliability. 10 refs., 1 tab., 7 figs.

A study on reliability of electro-hydraulic governor control system for large steam turbine in power plant

International Nuclear Information System (INIS)

Kang, Gu Hwa; Lee, Tae Hoon; Moon, Seung Jae; Lee, Jae Heon; Yoo, Ho Seon

2008-01-01

In this work, the right management procedure for hydraulic power oil will be discussed and suggested. A thermal power plant turbine should respond to the change of load status. However, to satisfy the frequency of alternating current, the revolution per minute should be kept constant. Therefore, by controlling the flow rate of the steam to the turbine, the governor satisfies the load variation without alternating the revolution per minutes of the turbine. To protect the governor, the hydraulic power unit should be managed carefully by controlling the quality and the flow rate of the oil

The HTR-10 test reactor project and potential use of HTGR for non-electric application in China

International Nuclear Information System (INIS)

Sun Yuliang; Zhong Daxin; Xu Yuanhui; Wu Zhongxin

1997-01-01

Coal is the dominant source of energy in China. This use of coal results in two significant problems for China; it is a major burden on the train, road and waterway transportation infrastructures and it is a significant source of environmental pollution. In order to ease the problems caused by the burning of coal and to help reduce the energy supply shortage in China, national policy has directed the development of nuclear power. This includes the erection of nuclear power plants with water cooled reactors and the development of advanced nuclear reactor types, specifically, the high temperature gas cooled reactor (HTGR). The HTGR was chosen for its favorable safety features and its ability to provide high reactor outlet coolant temperatures for efficient power generation and high quality process heat for industrial applications. As the initial modular HTGR development activity within the Chinese High Technology Programme, a 10MW helium cooled test reactor is currently under construction on the site of the Institute of Nuclear Energy Technology northwest of Beijing. This plant features a pebble-bed helium cooled reactor with initial criticality anticipated in 1999. There will be two phases of high temperature heat utilization from the HTR-10. The first phase will utilize a reactor outlet temperature of 700 deg. C with a steam generator providing steam for a steam turbine cycle which works on an electrical/heat co-generation basis. The second phase is planned for a core outlet temperature of 900 deg. C to investigate a steam cycle/gas turbine combined cycle system with the gas turbine and the steam cycle being independently parallel in the secondary side of the plant. This paper provides a review of the technical design, licensing, safety and construction schedule for the HTR-10. It also addresses the potential uses of the HTGR for non-electric applications in China including process steam for the petrochemical industry, heavy oil recovery, coal conversion and

Method for repairing a steam turbine or generator rotor

International Nuclear Information System (INIS)

Clark, R.E.; Amos, D.R.

1987-01-01

A method is described for repairing low alloy steel steam turbine or generator rotors, the method comprising: a. machining mating attachments on a replacement end and a remaining portion of the original rotor; b. mating the replacement end and the original rotor; c. welding the replacement end to the original rotor by narrow-gap gas metal arc or submerged arc welding up to a depth of 1/2-2 inches from the rotor surface; d. gas tungsten arc welding the remaining 1/2-2 inches; e. boring out the mating attachment and at least the inside 1/4 inch of the welding; and f. inspecting the bore

Evaluation of material integrity on electricity power steam generator cycles (turbine casing) component

International Nuclear Information System (INIS)

Histori; Benedicta; Farokhi; S A, Soedardjo; Triyadi, Ari; Natsir, M

1999-01-01

The evaluation of material integrity on power steam generator cycles component was done. The test was carried out on casing turbine which is made from Inconel 617. The tested material was taken from t anjung Priok plant . The evaluation was done by metallography analysis using microscope with magnification of 400. From the result, it is shown that the material grains are equiaxed

A theoretical analysis of flow through the nucleating stage in a low pressure steam turbine

International Nuclear Information System (INIS)

Skillings, S.A.; Walters, P.T.; Jackson, R.

1989-01-01

In order to improve steam turbine efficiency and reliability, the phenomena associated with the formation and growth of water droplets must be understood. This report describes a theoretical investigation into flow behaviour in the nucleating stage, where the predictions of a one-dimensional theory are compared with measured turbine data. Results indicate that droplet sizes predicted by homogeneous condensation theory cannot be reconciled with measurements unless fluctuating shock waves arise. Heterogeneous effects and flow turbulence are also discussed along with their implications for the condensation process. (author)

New low pressure (LP) turbines for NE Krsko

International Nuclear Information System (INIS)

Nemcic, K.; Novsak, M.

2004-01-01

During the evaluation of possible future maintenance strategies on steam turbine in very short period of time, engineering decision was made by NE Krsko in agreement with Owners to replace the existing two Low Pressure (LP) Turbines with new upgrading LP Turbines. This decision is presented with review of the various steam turbine problems as: SCC on turbine discs; blades cracking; erosion-corrosion with comparison of various maintenance options and efforts undertaken by the NE Krsko to improve performance of the original low pressure turbines. This paper presents the NEK approach to solve the possible future problems with steam turbine operation in NE Krsko as pro-active engineering and maintenance activities on the steam turbine. This paper also presents improvements involving retrofits, confined to the main steam turbine path, with major differences between original and new LP Turbines as beneficial replacement because of turbine MWe upgrading and return capital expenditures.(author)

Analysis of Precooling Injection Transient of Steam Generator for High Temperature Gas Cooled Reactor

Directory of Open Access Journals (Sweden)

Yan Wang

2017-01-01

Full Text Available After a postulated design basis accident leads high temperature gas cooled reactor to emergency shutdown, steam generator still remains with high temperature level and needs to be cooled down by a precooling before reactor restarts with clearing of fault. For the large difference of coolant temperature between inlet and outlet of steam generator in normal operation, the temperature distribution on the components of steam generator is very complicated. Therefore, the temperature descending rate of the components in steam generator needs to be limited to avoid the potential damage during the precooling stage. In this paper, a pebble-bed high temperature gas cooled reactor is modeled by thermal-hydraulic system analysis code and several postulated precooling injection transients are simulated and compared to evaluate their effects, which will provide support for the precooling design. The analysis results show that enough precooling injection is necessary to satisfy the precooling requirements, and larger mass flow rate of precooling water injection will accelerate the precooling process. The temperature decrease of steam generator is related to the precooling injection scenarios, and the maximal mass flow rate of the precooling injection should be limited to avoid the excessively quick temperature change of the structures in steam generator.

A CFD Analysis of Steam Flow in the Two-Stage Experimental Impulse Turbine with the Drum Rotor Arrangement

Directory of Open Access Journals (Sweden)

Yun Kukchol

2016-01-01

Full Text Available The aim of the paper is to present the CFD analysis of the steam flow in the two-stage turbine with a drum rotor and balancing slots. The balancing slot is a part of every rotor blade and it can be used in the same way as balancing holes on the classical rotor disc. The main attention is focused on the explanation of the experimental knowledge about the impact of the slot covering and uncovering on the efficiency of the individual stages and the entire turbine. The pressure and temperature fields and the mass steam flows through the shaft seals, slots and blade cascades are calculated. The impact of the balancing slots covering or uncovering on the reaction and velocity conditions in the stages is evaluated according to the pressure and temperature fields. We have also concentrated on the analysis of the seal steam flow through the balancing slots. The optimized design of the balancing slots has been suggested.

Extended fuel cycle operation for pressurized water reactor plants

International Nuclear Information System (INIS)

Silvestri, G.J. Jr.

1978-01-01

A nuclear steam turbine power plant system having an arrangement therein for extended fuel cycle operation is described. The power plant includes a turbine connected at its inlet to a source of motive fluid having a predetermined pressure associated therewith. The turbine has also connected thereto an extraction conduit which extracts steam from a predetermined location therein for use in an associated apparatus. A bypass conduit is provided between a point upstream of the inlet and the extraction conduit. A flow control device is provided within the bypass conduit and opens when the pressure of the motive steam supply drops beneath the predetermined pressure as a result of reactivity loss within the nuclear reactor. Opening of the bypass conduit provides flow to the associated apparatus and at the same time provides an increased flow orifice to maintain fluid flow rate at a predetermined level

Comparison of performances of full-speed turbine and half-speed turbine for nuclear power plants

International Nuclear Information System (INIS)

Wang Hu; Zhang Weihong; Zhang Qiang; Li Shaohua

2010-01-01

The steam turbines of nuclear power plants can be divided into the full-speed turbine and half-speed turbine. Different speed leads to differences in many aspects. Therefore, the rational speed is the key point in the selection of steam turbines. This paper contrasts the economy between the half-speed turbine and full-speed turbine, by calculating the relative internal efficiency of half-speed and full-speed steam turbines with the typical level of 1000 megawatt. At the same time, this paper also calculate the relative speed of high speed water drops in the last stage blade of half-speed turbine and full-speed turbine, to contrast the water erosion between the half-speed turbine and full-speed turbine. The results show that the relative internal efficiency of half-speed turbine is higher than that of the full-speed turbine, and that the security especially the ability of preventing water erosion of half-speed turbine is better than that of the full-speed turbine. (authors)

The effect of steam cycle conditions upon the economics and design of a sodium-cooled fast reactor

International Nuclear Information System (INIS)

Philpott, E.F.; Pounder, F.; Willby, C.R.

1978-01-01

The paper studies the effect of variation of steam and feedwater conditions upon the economics, design and layout of a sodium-cooled fast reactor. The parameters investigated are steam temperature and pressure, feedwater temperature, and boiler recirculation ratio. The paper also includes an assessment of the effects of associating the fast reactor with saturated steam cycle conditions. (author)

Design and development of gas turbine high temperature reactor 300 (GTHTR300)

International Nuclear Information System (INIS)

Kunitomi, Kazuhiko; Katanishi, Shoji; Takada, Shoji; Takizuka, Takakazu; Yan, Xing; Kosugiyama, Shinichi

2003-01-01

JAERI (Japan Atomic Energy Research Institute) started design and development of the high temperature gas cooled reactor with a gas turbine electric generation system, GTHTR300, in April 2001. Design originalities of the GTHTR300 are a horizontally mounted highly efficient gas turbine system and an ultimately simplified safety system such as no containment building and no active emergency core cooling. These design originalities are proposed based on design and operational experiences in conventional gas turbine systems and Japan's first high temperature gas cooled reactor (HTTR: High Temperature Engineering Test Reactor) so that many R and Ds are not required for the development. Except these original design features, devised core design, fuel design and plant design are adopted to meet design requirements and attain a target cost. This paper describes the unique design features focusing on the safety design, reactor core design and gas turbine system design together with a preliminary result of the safety evaluation carried out for a typical severe event. This study is entrusted from Ministry of Education, Culture, Sports, Science and Technology of Japan. (author)

On economic efficiency of nuclear power unit life extension using steam-gas topping plant

International Nuclear Information System (INIS)

Kuznetsov, Y.N.; Lisitsa, F.D.; Smirnov, V.G.

2001-01-01

The different options for life extension of the operating nuclear power units have been analyzed in the report with regard for their economic efficiency. A particular attention is given to the option envisaging the reduction of reactor power output and its subsequent compensation with a steam-gas topping plant. Steam generated at its heat-recovery boilers is proposed to be used for the additional loading of the nuclear plant turbine so as to reach its nominal output. It would be demonstrated that the implementation of this option allows to reduce total costs in the period of power plant life extension by 24-29% as compared with the alternative use of the replacing steam-gas unit and the saved resources could be directed, for instance, for decommissioning of a reactor facility. (authors)

Calculation of steam content in a draught section of a tank-type boiling water cooled reactor