scholarly journals THE WAVE PRESSING PLATE FOR PROTECTING COOLING WATERWAYS OF COASTAL POWER PLANTS

1984 ◽  
Vol 1 (19) ◽  
pp. 194 ◽  
Author(s):  
S.C. Chow ◽  
Frederick L.W. Tang ◽  
H.H. Hwung
Keyword(s):  
Power Plant ◽  
Water Surface ◽  
Nuclear Power ◽  
Power Plants ◽  
Wave Motion ◽  
Cooling Water ◽  
Northern Coast ◽  
Horizontal Plate ◽  
Hydraulics Laboratory ◽  
Power Plant Cooling

A horizontal plate laid on water surface to reduce the wave motion is proved to be effective theoretically and verified by model tests done at Tainan Hydraulics Laboratory. This principle has been put into practice on the northern coast of Taiwan for protecting a nuclear power plant cooling water intake against intruding waves. The design and construction of wave prevention works of such type are described succinctly in the paper. Also the effect of wave diminishing has been affirmed by measuring the respective waves heights outside and inside of the wave pressing plate.

scholarly journals Quantifying Restoration Offsets at a Nuclear Power Plant in Canada

2019 ◽  
Vol 64 (5) ◽  
pp. 593-607 ◽  
Author(s):  
Lawrence W. Barnthouse ◽  
Cherie-Lee Fietsch ◽  
David Snider
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Habitat Restoration ◽  
Cooling Water ◽  
Lake Huron ◽  
Life Stages ◽  
Eastern Shore ◽  
Fisheries Act

Abstract In Canada, the Fisheries Act requires all water takers to avoid, mitigate and offset fish losses. To satisfy the act’s requirements, operators of power plants are required to undertake habitat restoration projects to compensate for fish impinged and entrained at cooling water intake structures. Scaling the quantity of restoration needed, and measuring whether adequate compensation has been achieved, requires a metric that expresses the losses and gains in comparable units. Development of such a metric is especially difficult in the case of power plants, because the losses often consist of a mix of species and life stages that are very different from those produced by technically feasible restoration projects. This paper documents the method that has been developed for quantifying offsets for impingement and entrainment at the Bruce Generating Stations on the eastern shore of Lake Huron, and demonstrates how the method is being used to estimate the offset to be provided by removal of a dam on the nearby Saugeen River.

Ultrasonic Inspection of Large Diameter Polyethylene Pipe Used in Nuclear Power Plant

2014 ◽  
Author(s):  
Jianfeng Shi ◽  
Dongsheng Hou ◽  
Weican Guo ◽  
Yaoda Zhou ◽  
Xia Chen ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Large Diameter ◽  
Ultrasonic Inspection ◽  
Water System ◽  
Cooling Water ◽  
Operating Pressure ◽  
Traditional Natural

Polyethylene (PE) pipe has many advantages such as good flexibility, corrosion resistance and long service life. It has been introduced into nuclear power plants for transportation of cooling water both in U.S. and Europe. Recently, one Chinese nuclear power plant in Zhejiang Province also introduced four polyethylene pipelines in essential cooling water system with operating pressure of 0.6MPa and operating temperature of no more than 60°C. The PE pipes used in this nuclear power plant are DN762 SDR9 (30in OD, 3.3in wall), which are much larger and thicker than traditional natural gas PE pipe. As the pipe wall is so thick that the ultrasonic phased array instrument used in inspection of PE pipe with diameter less than 400mm has been improved. Results of field inspection in the Sanmen nuclear plant are reported, and the presented ultrasonic inspection technique proves to be effective for high density polyethylene (HDPE) pipe of large size in nuclear power plant.

Calculation of Bounding Pressures Due to Condensation-Induced Water Hammer at the Davis-Besse Nuclear Power Plant in Response to Generic Letter 96-06

2003 ◽  
Author(s):  
G. Thomas Elicson ◽  
James P. Burelbach ◽  
Theodore A. Lang
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Water Flow ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Cooling Water ◽  
Water Hammer ◽  
Service Water ◽  
Water Columns

The U.S. NRC is currently evaluating nuclear plant responses to Generic Letter (GL) 96-06, “Assurance of Equipment Operability and Containment Integrity During Design-Basis Accident Conditions” [1]. GL 96-06 is concerned with potential two-phase flow and water hammer conditions that could be present in the cooling water systems of nuclear power plants during design-basis accidents. Nuclear power plants rely on large capacity service water pumps to supply cooling water flow, via an extensive pipe network, to heat exchangers such as room coolers, pump lube oil coolers, and containment air coolers (CACs), for normal and abnormal plant operation. Following a postulated a loss of offsite power (LOOP) event, the normal electrical power supply to the service water pump would be lost resulting in a 20 to 30 second cooling water flow interruption while a diesel generator is started and the service water pump load is sequenced onto the diesel generator. In power plants, such as the Davis-Besse Nuclear Power Plant with open service water systems that draw from a lake or a river and supply safety-related CAC heat exchangers located 30 to 40 feet above the pump outlet, this could lead to cold water column separation in the heat exchanger supply and return piping. If a loss of coolant accident (LOCA) occurs coincident with the LOOP, then boiling in the CAC heat exchanger tubes could occur, as well. Upon restoration of the cooling water flow, dynamic loading could be expected as steam condenses and water columns rejoin. The TREMOLO computer program [2,3] has been used to calculate dynamic thermal hydraulic response and reaction forces in service water piping systems for several nuclear power plants in response to GL 96-06. A consistent result obtained in each of these GL 96-06 analyses is that the LOOP + LOCA scenario produces the bounding loads rather than the LOOP-only scenario. This result seemingly contradicts current industry thinking which suggests that because the water columns are colder and the void fraction lower during LOOP-only scenarios, the LOOP-only loads should be bounding [4,5,6]. While the physics supports the conclusion that the rejoining of colder water columns will generally yield the largest water hammer pressure rise, when actual plant geometry and credible accident scenarios are analyzed, a different picture emerges. This paper couples insights obtained from the GL 96-06 TREMOLO analysis of the Davis-Besse Nuclear Power Plant with independent hand calculations and experimental evidence to support the conclusion that the LOCA+LOOP scenario will produce the bounding loads in service water piping systems.

Study on the Interaction Between Safety-Related and Non Safety-Related Items in the Component Cooling Water System Room of the Qinshan Nuclear Power Plant in the Earthquake Condition

2020 ◽  
Author(s):  
Liang Zhang ◽  
Gang Xu ◽  
Yue Wang ◽  
Li Chen ◽  
Shao Chong Zhou
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Water System ◽  
Cooling Water ◽  
Life Extension ◽  
Main Body ◽  
Cooling Water System ◽  
The Impact

Abstract Safety-related items in nuclear power plants are now generally placed separately from the non-safety-related items, but it was not strictly required before. Therefore, it is very important to study whether the non-safety-related items will affect the safety-related items when they are dropped down in an earthquake situation, which determines the safety of a nuclear power plant and its future life extension applications. This research was based on the cooling water system room with the safety and non-safety related items installed together, as an example to study whether the non-safety-related items such as vent pipes and DN50 fire fighting pipes arranged above will damage the DN300 pipes and valves arranged below when earthquakes occur. For the experiments, the relative positions of objects in the room was reproduced by 1: 1. The pressure-holding performance of the pipe was used as a criterion for the damage. The research results of the experiments show that when the 10-meter-long DN50 pipe was dropped from the position of 8 meters height and the 8-meter-long vent dropped from position of 3.6 meters height, they do not affect the integrity of the DN300 valve and pipe below. After the experiment, pressure drop in two hours for the pipe is less than 0.1%. The main body of the valve does not fail neither. The numerical simulation study also shows that there is no failure phenomenon in the simulation as well. Compared with the test results, the impact acceleration and the vent deformation both have the same trend.

Ultrasonic Inspection of Electrofusion Joints of Large Polyethylene Pipes in Nuclear Power Plants

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
Jinyang Zheng ◽  
Dongsheng Hou ◽  
Weican Guo ◽  
Xiaoming Miao ◽  
Yaoda Zhou ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Ultrasonic Inspection ◽  
Cooling Water ◽  
Operating Pressure ◽  
Hdpe Pipe ◽  
Hdpe Pipes

High-density polyethylene (HDPE) pipe has many advantages such as good flexibility, corrosion resistance, and long service life. It has been introduced into nuclear power plants for transportation of cooling water in U.S. and Europe. Recently, four HDPE pipelines (PE4710) were used in essential cooling water system with operating pressure of 0.6 MPa and operating temperature of no more than 60 °C in a newly established AP1000 nuclear power plant in Zhejiang, China. The outside diameter and thickness are 30 in. and 3.3 in., respectively, which are much larger and thicker than traditional HDPE pipe for natural gas. This brought forward a challenge for nondestructive testing (NDT) and safety assessment of such pipes. In this paper, a solution for inspecting electrofusion (EF) joints of thick-walled HDPE pipes is presented, and the results of an on-site inspection of the nuclear power plant are revealed. To expand the thickness up-limit of previously developed ultrasonic-phased array instrument, an optimization method was proposed by calculating weighing effects of different testing parameters and introducing the concept of overall performance according to practical requirement, by comprehensively considering sensitivity, penetration, signal-to-noise ratio (SNR), resolution, and accuracy. Typical defects were found in field inspection. The result shows that the presented technique is capable of inspecting EF joints for connecting large-size HDPE pipes used in nuclear power plants.

Fuzzy multi-objective decision making approach for nuclear power plant installation

2020 ◽  
Vol 39 (5) ◽  
pp. 6339-6350
Author(s):  
Esra Çakır ◽  
Ziya Ulukan
Keyword(s):  
Linear Programming ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Energy Supply ◽  
Energy Demand ◽  
Nuclear Power ◽  
Power Plants ◽  
Total Duration ◽  
Objective Functions ◽  
Multi Objective

Due to the increase in energy demand, many countries suffer from energy poverty because of insufficient and expensive energy supply. Plans to use alternative power like nuclear power for electricity generation are being revived among developing countries. Decisions for installation of power plants need to be based on careful assessment of future energy supply and demand, economic and financial implications and requirements for technology transfer. Since the problem involves many vague parameters, a fuzzy model should be an appropriate approach for dealing with this problem. This study develops a Fuzzy Multi-Objective Linear Programming (FMOLP) model for solving the nuclear power plant installation problem in fuzzy environment. FMOLP approach is recommended for cases where the objective functions are imprecise and can only be stated within a certain threshold level. The proposed model attempts to minimize total duration time, total cost and maximize the total crash time of the installation project. By using FMOLP, the weighted additive technique can also be applied in order to transform the model into Fuzzy Multiple Weighted-Objective Linear Programming (FMWOLP) to control the objective values such that all decision makers target on each criterion can be met. The optimum solution with the achievement level for both of the models (FMOLP and FMWOLP) are compared with each other. FMWOLP results in better performance as the overall degree of satisfaction depends on the weight given to the objective functions. A numerical example demonstrates the feasibility of applying the proposed models to nuclear power plant installation problem.

Human reliability in non-destructive inspections of nuclear power plant components: modeling and analysis

2019 ◽  
Vol 7 (2B) ◽  
Author(s):  
Vanderley Vasconcelos ◽  
Wellington Antonio Soares ◽  
Raissa Oliveira Marques ◽  
Silvério Ferreira Silva Jr ◽  
Amanda Laureano Raso
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Human Factors ◽  
Nuclear Power ◽  
Power Plants ◽  
Failure Modes ◽  
Cooling System ◽  
Human Reliability ◽  
Non Destructive ◽  
Plant Components

Non-destructive inspection (NDI) is one of the key elements in ensuring quality of engineering systems and their safe use. This inspection is a very complex task, during which the inspectors have to rely on their sensory, perceptual, cognitive, and motor skills. It requires high vigilance once it is often carried out on large components, over a long period of time, and in hostile environments and restriction of workplace. A successful NDI requires careful planning, choice of appropriate NDI methods and inspection procedures, as well as qualified and trained inspection personnel. A failure of NDI to detect critical defects in safety-related components of nuclear power plants, for instance, may lead to catastrophic consequences for workers, public and environment. Therefore, ensuring that NDI is reliable and capable of detecting all critical defects is of utmost importance. Despite increased use of automation in NDI, human inspectors, and thus human factors, still play an important role in NDI reliability. Human reliability is the probability of humans conducting specific tasks with satisfactory performance. Many techniques are suitable for modeling and analyzing human reliability in NDI of nuclear power plant components, such as FMEA (Failure Modes and Effects Analysis) and THERP (Technique for Human Error Rate Prediction). An example by using qualitative and quantitative assessesments with these two techniques to improve typical NDI of pipe segments of a core cooling system of a nuclear power plant, through acting on human factors issues, is presented.

scholarly journals Python TensorFlow Big Data Analysis for the Security of Korean Nuclear Power Plants

Electronics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1467
Author(s):  
Sangdo Lee ◽  
Jun-Ho Huh ◽  
Yonghoon Kim
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Network Traffic ◽  
Nuclear Power ◽  
Power Plants ◽  
Security Requirements ◽  
Republic Of Korea ◽  
Continuous Data ◽  
Cyber Attack ◽  
The Republic

The Republic of Korea also suffered direct and indirect damages from the Fukushima nuclear accident in Japan and realized the significance of security due to the cyber-threat to the Republic of Korea Hydro and Nuclear Power Co., Ltd. With such matters in mind, this study sought to suggest a measure for improving security in the nuclear power plant. Based on overseas cyber-attack cases and attacking scenario on the control facility of the nuclear power plant, the study designed and proposed a nuclear power plant control network traffic analysis system that satisfies the security requirements and in-depth defense strategy. To enhance the security of the nuclear power plant, the study collected data such as internet provided to the control facilities, network traffic of intranet, and security equipment events and compared and verified them with machine learning analysis. After measuring the accuracy and time, the study proposed the most suitable analysis algorithm for the power plant in order to realize power plant security that facilitates real-time detection and response in the event of a cyber-attack. In this paper, we learned how to apply data for multiple servers and apply various security information as data in the security application using logs, and match with regard to application of character data such as file names. We improved by applying gender, and we converted to continuous data by resetting based on the risk of non-continuous data, and two optimization algorithms were applied to solve the problem of overfitting. Therefore, we think that there will be a contribution in the connection experiment of the data decision part and the optimization algorithm to learn the security data.

scholarly journals Using CO2 as a Cooling Fluid for Power Plants: A Novel Approach for CO2 Storage and Utilization

2021 ◽  
Vol 11 (11) ◽  
pp. 4974
Author(s):  
Tran X. Phuoc ◽  
Mehrdad Massoudi
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Saturated Vapor ◽  
Co2 Storage ◽  
Storage Container ◽  
Cooling Fluid ◽  
Capital Costs ◽  
Dry Air ◽  
Novel Approach ◽  
Power Plant Cooling

To our knowledge, the potential use of CO2 as a heat-transmitting fluid for cooling applications in power plants has not been explored very extensively. In this paper, we conduct a theoretical analysis to explore the use of CO2 as the heat transmission fluid. We evaluate and compare the thermophysical properties of both dry air and CO2 and perform a simple analysis on a steam-condensing device where steam flows through one of the flow paths and the cooling fluid (CO2 or air) is expanded from a high-pressure container and flows through the other. Sample calculations are carried out for a saturated-vapor steam at 0.008 MPa and 41.5 °C with the mass flow rate of 0.01 kg/s. The pressure of the storage container ranges from 1 to 5 MPa, and its temperature is kept at 35 °C. The pressure of the cooling fluid (CO2 or dry air) is set at 0.1 MPa. With air as the heat-removing fluid, the steam exits the condensing device as a vapor-liquid steam of 53% to 10% vapor for the container pressure of 1 to 5 MPa. With CO2 as the heat-removing fluid, the steam exits the device still containing 44% and 7% vapor for the container pressure of 1 MPa and 2 MPa, respectively. For the container pressure of 3 MPa and higher, the steam exits the device as a single-phase saturated liquid. Thus, due to its excellent Joule–Thomson cooling effect and heat capacity, CO2 is a better fluid for power plant cooling applications. The condensing surface area is also estimated, and the results show that when CO2 is used, the condensing surface is 50% to 60% less than that when dry air is used. This leads to significant reductions in the condenser size and the capital costs. A rough estimate of the amount of CO2 that can be stored and utilized is also carried out for a steam power plant which operates with steam with a temperature of 540 °C (813 K) and a pressure of 10 MPa at the turbine inlet and saturated-vapor steam at 0.008 MPa at the turbine outlet. The results indicate that if CO2 is used as a cooling fluid, CO2 emitted from a 1000 MW power plant during a period of 250 days could be stored and utilized.

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