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Ronald G. Ballinger. Van der Helm, Mark Johan, 1972- Massachusetts Institute of Technology. Dept. of Nuclear Engineering. Massachusetts Institute of Technology. Department of Nuclear Engineering Massachusetts Institute of Technology. Department of Nuclear Science and Engineering 2005-08-23T15:57:32Z 2005-08-23T15:57:32Z 2000 2001 http://hdl.handle.net/1721.1/8867 48755245 Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, February 2001. Includes bibliographical references (leaves 198-204). Flow Accelerated Corrosion (FAC) is the most prevalent material degradation mechanism for low carbon steel in steam-water flow systems. The band of uncertainty in predictions of wear rate due to FAC spans one to two orders of magnitude. Such a wide range of uncertainty inhibits the ability to devise safe and economical repair and replacement schedules. The goal of this thesis is to reduce uncertainty of predictions of wear caused by FAC. Reduction in the uncertainty in FAC wear rate predictions is achieved through the development of a new predictive FAC model, the incorporation of this model in a flow system analysis environment, and the use of this environment to identify improved methodologies for predicting FAC wear rate. The new FAC model is based on a published empirical model, published data, and physical mechanisms identified to be significant in the wear process. The new FAC model is shown to have less uncertainty for single phase lab data and single and two phase plant data. The flow system analysis environment is an interactive program that calculates parameters relevant to the FAC phenomenon based on plant description. Functionality of this environment is validated for each of the four calculations it performs: thermodynamic, thermal hydraulic, chemistry, and degradation rate. Additionally, this environment can be used to analyze contributions to uncertainty that are not yet identified. This environment was used to analyze the contribution to uncertainty from the current method of incorporating chemistry parameters in predictions of FAC wear. Based on this analysis, suggestions are made to improve these methods, thereby reducing prediction uncertainty and improving the knowledge necessary for safer and more economical plant operation. by Mark Johan van der Helm. Ph.D. 238 leaves 17574312 bytes 17574071 bytes application/pdf application/pdf eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Nuclear Engineering. Power plant degradation : a modular secondary plant and integral flow accelerated corrosion model Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="ada7f143-6e01-490b-9974-ff2c7c99b171"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Power plant degradation : a modular secondary plant and integral flow accelerated corrosion model</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2001</PublicationDate> <Authors> <Author> <DisplayName>Van der Helm, Mark Johan, 1972-</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Nuclear Engineering.</Keyword> <Abstract>Flow Accelerated Corrosion (FAC) is the most prevalent material degradation mechanism for low carbon steel in steam-water flow systems. The band of uncertainty in predictions of wear rate due to FAC spans one to two orders of magnitude. Such a wide range of uncertainty inhibits the ability to devise safe and economical repair and replacement schedules. The goal of this thesis is to reduce uncertainty of predictions of wear caused by FAC. Reduction in the uncertainty in FAC wear rate predictions is achieved through the development of a new predictive FAC model, the incorporation of this model in a flow system analysis environment, and the use of this environment to identify improved methodologies for predicting FAC wear rate. The new FAC model is based on a published empirical model, published data, and physical mechanisms identified to be significant in the wear process. The new FAC model is shown to have less uncertainty for single phase lab data and single and two phase plant data. The flow system analysis environment is an interactive program that calculates parameters relevant to the FAC phenomenon based on plant description. Functionality of this environment is validated for each of the four calculations it performs: thermodynamic, thermal hydraulic, chemistry, and degradation rate. Additionally, this environment can be used to analyze contributions to uncertainty that are not yet identified. This environment was used to analyze the contribution to uncertainty from the current method of incorporating chemistry parameters in predictions of FAC wear. Based on this analysis, suggestions are made to improve these methods, thereby reducing prediction uncertainty and improving the knowledge necessary for safer and more economical plant operation.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>