Computer simulation of the reliability of the heat exchange surface of the steam turbine condenser

The aim of the article is to demonstrate the relationship between the adaptive regulation of the heat exchange surface to specific operating conditions of a steam turbine condenser and the reliability and availability of this surface in a specific period of time. The article exemplifies the relationship between the settings of the condenser heat exchange surface and the resulting changes in the reliability structures of this surface. The method of creating a mathematical model of reliability estimation, which is characterized by the variability of the reliability structures of the heat exchange surface in relation to specific operating conditions in a specific period of time, was indicated. Then, exemplary simulations of the adaptation of reliability structures of specific pipe systems constituting the condenser’s heat exchange surface to specific processes of operation of this condenser are presented. The simulations refer to the time-varying thermal loads of the condenser, the time-varying mean thickness of the sediments, and changes in the temperature of the cooling water at the point of its intake over time. The adaptation of certain reliability structures consists in the adaptation of specific systems of pipes through which the cooling water flows to the currently existing operating conditions of the condenser in order to maintain the desired reliability of the heat exchange surface for a specified time. This is done by enabling or disabling the flow of cooling water through a given number of pipes in specific systems under given operating conditions. On the basis of computer simulations, the reliability functions, and the availability functions of the subsystem under consideration were estimated.

Mathematical model of a steam turbine condenser

The paper analyses the existing calculation methods for steam turbine condenser. The refined methods for calculating the condenser have also been considered. The dependency of the vapor pressure in the condenser on the temperature of the cooling water and the steam flow rate into the condenser have been considered. It can be seen from the obtained dependencies that the calculation of the condenser according to the ARTI and HEI (USA) methods coincides with the passport data. It is recommended to use the ARTI and HEI (USA) techniques for equipment diagnostics, and to use the KTP and USTU-UPI techniques when studying ways to increase the efficiency of the condenser. The mathematical model of the KG2-6200 condenser has been tested at the Almaty СHPP-2.

Calculated Determination of the Seismic Resistance of Nuclear Power Plant Equipment

An algorithm to confirm the seismic resistance of equipment by a calculation method is proposed, and the limits of its application are determined. A mathematical model of the equipment is developed, and an example of the determination of natural frequencies and stresses for a three-dimensional structure is given. Two main types of calculation were used – static and dynamic. In the static calculation, the stress-strain state of a structure was determined. The values of the obtained stresses were compared with the allowable ones for the materials used, on the basis of which conclusions were made about the strength of the structure under seismic effects. The dynamic calculation resulted in the determination of the rigidity of the structure. The comparison of the stress values obtained for this equipment allowed us to make a conclusion regarding its resistance to seismic effects. The seismic resistance of the equipment was estimated on the example of the K-1000-60 / 1500 steam turbine condenser, and calculated at a seismic intensity of 6 points on the MSK-64 seismic intensity scale. In the course of solving this problem, results of the stress distribution in the housing and other structural elements of the condenser due to the action of combined normal operation and design-basis seismic loads were obtained. The seismic resistance of the equipment was calculated using the finite element method. This allowed us to present a solid body in the form of a set of individual finite elements that interact with each other in a finite number of nodal points. To these points are applied some interaction forces that characterize the influence of the distributed internal stresses applied along the real boundaries of adjacent elements. To perform such a calculation in CAD modeling software, a three-dimensional model was created. The obtained geometric model was imported into the software package, which significantly reduced complexity. The use of the calculation method allows us to significantly reduce the amount of testing when confirming the seismic resistance of equipment. Results of the assessment of the spatial complex stress state of the steam turbine condenser design due to the action of combined normal operation and design-basis seismic loads are obtained.

Investigating the dearating hotwell working regimes of the PT-60-130/13 steam turbine

THE PURPOSE. To consider the problems of the increasing dissolved oxygen concentration in feedwater, especially after the condensate pumps. To estimate the opportunity of the vacuum thermic deaeration intensification inside the PT-60-130/13 LMZ steam turbine condenser to reduce the feedwater system rate of corrosion. Perform a thermal test of the external deaerating hotwell, which provides reducing dissolved oxygen concentration by the hot drains and recirculating feedwater. To evaluate the march of the dissolved oxygen concentration in feedwater after the inclusion of the deaerating hotwell. METHODS. The thermal test of the external deaerating hotwell was chosen for evaluating water deaeration. RESULTS. In this paper, the results of the thermal tests are given. The relation of the dissolved oxygen concentration from heating fluid flow is also presented. CONCLUSION. The use of the external deaerating hotwell allows achieving dissolved oxygen concentration below the norms established by the сode of operation for electrical power plants and grids to ensure the maintenance of an acceptable water-chemical regime of the feedwater. During the tests, the dissolved oxygen concentration decreased by 70% and reached a value of 8 mcg/dm3. The deaerating hotwell of the considered type can be recommended for the operation, especially during start-up modes and modes with the low thermal load on the condenser cooling surface.

Methodology for studying the quality of steam condensate and cooling water of a steam turbine condenser

Monitoring the suction of cooling water into steam with measurements of , H and pH of condensate is simultaneously a characteristic of the water-chemical regime of the main loop and the system of circulating (or direct-flow) cooling and has attracted increased attention in recent years. This is due both to the signif-icant suction of cooling water into the condensing steam at the power units of TPPs and NPPs, and to the appearance on the market of new reagents – deposit and corrosion inhibitors. Investigation of the behavior of such substances under conditions of a recirculating cooling system is a complex task, the solution of which depends on many factors. The purpose of the scientific research was to develop a methodology for instrumental (automated) control based on measurements of electrical conductivity ( and H) and pH, which makes it possible to reduce the number of controlled parameters of circulating water, to increase the information content of the measurement results in terms of the amount of suction of circulating water into condensing steam.The implementation of the task in laboratory conditions was carried out using the experi-mental stand «Installation of reverse osmosis and chemical desalination», which provides the ability to measure the specific electrical conductivity of direct () and H-cationized (H) samples of steam condensate and calculate a number of normalized parameters according to the author's algorithm. A large volume of chemical quality control of the make-up and circulating water in the recirculating cooling system limits the efficiency of research and requires large labor costs. In this case, the method of indirect (calculated) deter-mination of the concentrations of ionic impurities can be used by calculating them according to the author's algorithm using the measured values of electrical conductivity and pH.Two laboratory units are presented: reverse osmosis and chemical desalination; modeling the water regime of recirculating cooling systems. A method is proposed for studying the state of the water-chemical regime of a steam turbine condenser both from the side of steam and from the side of cooling water. Examples of using the methodology for calculating the characteristics of steam condensate and cooling water are given. It is shown that the use of instrumental measurements of specific electrical conductivity and pH makes it possible to reduce the volume of laboratory chemical control of aqueous media, to increase the efficiency and information content of the measurement results.A patent for an invention of the Russian Federation No. 2658020 was obtained for a laboratory installation of reverse osmosis and chemical desalination. A distinctive feature of the installation is the ability to obtain deeply demineralized water with a specific electrical conductivity of less than 0,2 μS / cm with the subsequent preparation of extremely dilute solutions. The second laboratory unit simulates the water regime of recirculating cooling systems and can be used in the operating conditions of the power plant. The scientific novelty of the method for the chemical quality control of steam condensate and circulating water consists in the use of an original author's algorithm, which provides the calculation of a number of standardized indicators based on the measured values of electrical conductivity and pH.

Analisa Efisiensi Termal Turbin, Kondensor dan Menara Pendingin pada Pembangkit Listrik Tenaga Panas Bumi

Geothermal power plants have similarities with other generated power plants such as coal, gas or nuclear power that is converting heat energy into electricity. When the geothermal fluid is extracted from the production well, it will pass through many different processes or equipment on the way to the power plant. During this process the geothermal fluid loses unused energy to generate power. The overall efficiency of the power plant can be affected by several parameters, one of them is design of power plant. This study attempts to analysis the thermal efficiency of the generating components: turbine, condenser and cooling tower at one of geothermal power plant in Indonesia. So, we can know how the performance of the component, whether the component is running well or not. From the calculation results obtained that the turbine, condenser and cooling tower currently still operate well with the value of thermal efficiency of 80%-100%.

Study of the Rostov nuclear power plant efficiency operation under increased vacuum value

In this study, the influence of the cooling water temperature on the thermal efficiency of a conceptual pressurized-water reactor nuclear- power plant is studied. The change in the cooling water temperature can be experienced due to the seasonal changes in climatic conditions at plant site. The article presents the results of technical and economic parameters study of nuclear power unit’s operation under increased vacuum value. Investigated seasonal variations of cooling water temperature, cooling water temperature influence on the vacuum temperature in the turbine condenser, and changing the basic technical and economic performance of nuclear power station. The mathematical model of calculation the nuclear power plant operation for a 1000 MW power unit was developed.