The most important requirement for running a nuclear power plant safely is having a reliable safety system, especially during the emergency shutdown condition. For performing a scrutiny load flow and voltage drop study a detailed and comprehensive electrical model for the emergency electrical distribution system of the Trojan Nuclear Power Plant has been developed. This model includes the representation of the transformers, circuit breakers, motors, cables and load data from 4160 volts level down to the individual 480 volts loads.

No description available.

Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / This report explores the requirements for the design and analysis of concrete containment and shows how newer material technologies such as self-consolidating concrete (SCC) and fiber reinforcement could assist in the constructability and durability of new nuclear power plant facilities. SCC for example, enables concrete to flow in the forms around the reinforcement and provides a more uniform adhesion with the reinforcement. Additionally, fiber reinforcement in the concrete mix increases bonding capability, thus making the concrete less likely to fracture. In particular, the ease of constructability benefits offshore floating nuclear power plants and preapproved modular power plants. To differentiate, the offshore plant would employ the assembly line to make all the plants the same while the modular plant, designed to be used anywhere, is not site specific and is typically smaller. Regarding research method, the report starts with the history of the nuclear industry in the United States, including the last nuclear power plant constructed, clarifying that nuclear energy was first harnessed for a submarine propulsion system before being employed to generate electricity. After these early endeavors, two major accidents, Three Mile Island (March 28, 1979) and Chernobyl (April 26, 1986), provided information regarding the lack of safety of nuclear power plant design and operation. Since the containment building is the focus of this report, recognizing the loads and the load combinations for design was the next step in research. Following that, the next step was to determine the design considerations and analyze the containment structure. New material technologies clearly have opened the door to new construction techniques, and the combination of new materials and methods offers structural engineers opportunity to build inherently safer nuclear power plants.

As a critical public safety-related structure, the long-term integrity of post-tensioned concrete containment buildings (PCCs) is necessary for continued operation of the reactors they house. In 2009, during preparations for a steam generator replacement, extensive subsurface laminar cracking was identified in a portion of the Crystal River 3 (CR3) PCC in Florida, and the plant was permanently shut down in 2013. This study investigates potential contributing factors to the identified cracking with particular focus on the effects of high early-age temperatures on the cracking risk of the concrete, on the development of the concrete properties, and on the late-age structural behavior of the concrete. Two planar, full-scale mock-ups of a portion of the CR3 PCC were constructed and instrumented with temperature and strain gauges to monitor the thermal and mechanical behavior during representative concrete curing and post-tensioning loading. Standard- and match-cured concrete specimens were tested for determination of the time- and temperature-dependent development of thermal and mechanical concrete properties, and hydration parameters were determined for the mock-up cement paste for modeling the heat generation in the concrete. These properties and parameters were utilized in 3D finite element analysis of the mock-ups in COMSOL Multiphysics and compared with experimental results. Non-destructive evaluation via shear wave tomography was conducted on the mock-ups to identify flaws and determine the effectiveness of the methods for identifying delaminations between post-tensioning ducts approximately 10 inches beneath the concrete surface. Though early-age thermal stresses were determined not to have caused cracking in the mock-ups, the high early-age concrete temperatures resulted in decreased late-age mechanical properties that were shown to contribute to greater concrete cracking risk when the mock-up was post-tensioned. Tensile stresses exceeding the tensile strength of the concrete were identified along the post-tensioning ducts when biaxial post-tensioning loads were applied in finite element analysis, but the stresses decreased rapidly with increased distance from the ducts. Through parametric modeling, increasing the tensile strength of the concrete was identified as an effective means of reducing the cracking risk in PCCs. Additionally, relationships between the mechanical properties for the standard- and match-cured specimens were identified that could enable prediction of in-place or match-cured concrete properties based only on the results of tests on fog-cured specimens.

This study aims to improve the modeling of partial SCRAM in the BISON plant model for the Forsmark 2 nuclear reactor after power uprate. Validation of the BISON model against tests performed from March to May in 2013 have shown that this is one of the areas in which there is room for improvement. After partial SCRAM is performed, the model underestimates the reactor power, recirculation flow and steam flow when compared to the measurement data. In BISON the partial SCRAM is modeled using a relative control rod effect vector (ASC vector). The aim is to replace the old values in this vector to improve the model. The new model was shown to give an improved result for the reactor power, recirculation flow and steam flow. The study gives recommendations on how to apply the new model and what values of the relative control rod effect vector that can be used in the future.

海岸地帶係位處陸地與海洋交會之帶狀區域，自然孕育了珍貴且富變化的資源，能提 供高經濟、遊憩、教育、研究、生態保護及國土保安等多樣化使用。惟此等資源甚為 脆弱且不具復原性，一旦遭受破壞，將難以恢復，而遠失去其效用。 台灣土地資源極為有限，近二十年來，因為人口增加，產業結構轉型，對於不同型態 土地的需求日益殷切，而海岸土地具無主資源之特性，遂成為公、私部門競相使用的 對象。由於缺乏一套整體性的規劃與管理制度，致使海岸土地利用所衍生的問題方興 未艾，而這些問題正是以往海岸土地利用不當所累聚的環境惡果。 本研究承續上述問題，首先探討土地資源規劃與管理相關理論及美、日、荷等國海岸 土地資源規劃與管理的理念與精神，以作為本研究的理論基礎。 其次，透過實地訪問調查（使用者、管理者）並選擇彰濱工業區與核能四廠預定廠址 作為實例分析，分析重點為海岸土地資源競用與衝突之根源、政府所扮演的角色以及 規劃與管理之功能。根據分析結果，進一步檢視海岸地帶現行規劃與管理體制之缺失 。 從規劃與管理的角度來看，海岸地帶牽涉到陸域與水域二個方面，所以管轄機關職權 的複雜與重疊，法規的零散以及基於政治層面的考量，都構成規劃與管理的困難，而 海岸地帶規劃與管理的功能在於如何配置資源？建立使用的優先次序、整合法規以及 管理策略等。在這種思想結構下，本研究提出「動態的系統規劃與管理架構」，就政 策、法規、土地使用分派計畫、管理機構等作一詳盡的改革建議。整個架構力求與現 行體制相互配合，俾作為未來台灣地區海岸地帶長期發展規劃與管理之參考。

<p>Electrical production in Sweden today is mainly from nuclear and hydro power. However, there is large increase in renewable energy like wind power and the installed new capacity goals are large. Several electrical production sources are important for the sustainability of the energy system. Maintenance is an approach for keeping a system sustainable. The importance of structured maintenance for reliable electrical production systems triggers the development of qualitative and quantitative maintenance management methods. Examples of these methods are Reliability-Centered Maintenance (RCM) which is a structured qualitative approach that focuses on reliability when planning maintenance, and Reliability Centered Asset Management (RCAM) which is a development of RCM into a quantitative approach with the aim to relate preventive maintenance to total maintenance cost and system reliability.</p><p>This thesis presents models, as applications of RCAM, based on the methods of Life Cycle Cost (LCC) and mathematical optimization, applied to wind and nuclear power plants. Both deterministic and stochastic approaches have been used and the proposed models are based on the <em>Total Cost</em> model, which summarizes costs for maintenance and production loss, and the <em>Aircraft </em>model, which is an opportunistic maintenance optimization model. Opportunistic maintenance is preventive maintenance performed at opportunities. The wind power applications in this study show on different ways to cover costs of condition monitoring systems (CMS) and further on economic benefits of these when uncertainties of times to failure are included in the model. The nuclear power applications show on that the optimization model is dependent on the discount rate and that a high discount rate gives more motivation for opportunistic replacements. When put into a stochastic framework and compared to other maintenance strategies it is shown that an extended opportunistic maintenance optimization model has a good overall performance, and that it, for high values of the constant cost of performing maintenance, is preferable to perform opportunistic maintenance. The proposed models, applied to wind and nuclear power plants, could be extended and adapted to fit other components and systems.</p> / Reliability and cost centered maintenance methods

Pressurizer modeling for predicting the dynamic pressure of the PIUS system is presented. The transient behavior of this model for the PIUS system was investigated. The validity of this model for the PIUS system is limited to transients that are neither too large nor too long in duration. For example, the model is not capable of describing events following a complete loss of liquid for the pressurizer. However, the model can be used for qualitative prediction of the PIUS system behavior for a wide variety of severe transients. A review of pressurizer modeling indicates that the neglecting of the change in the internal energy of the subcooled water during transients is an acceptable assumption. The inherently safe feature of the PIUS system was confirmed through the self-shutdown of the reactor or, in some cases, through reactor power reduction as a result of the ingress of the pool boric acid solution into the primary system. This dynamic model was constructed of three major components: (1) The primary loop, (2) The secondary loop, and (3) The natural convection loop through the pool. A lumped parameter model, uniform heat transfer, and point kinetics have been the main approximations in this model. Other approximations are mentioned during the modeling of each component of the model. The dynamic model was simulated using the DARE-P continuous system simulation language which was developed in the Electrical Engineering Department at the University of Arizona.

No description available.

The purpose of this research was a proof of concept using a fan motor stator as transducer to monitor motor rotor and attached axial fan for mechanical motion. The proof was to determine whether bearing faults and fan imbalances could be detected in vane-axial fans using Motor Electrical Signature Analysis (MESA). The data was statistically analyzed to determine if the MESA systems could distinguish between baseline conditions and discrete fault frequencies for the three test conditions: bearing inner race defect, bearing outer race defect, and fan imbalance. The statistical conclusions for these proofs of concept were that MESA could identify all three faulted conditions.