Thermal barrier coating life prediction model development, phase 1

The objective of this program was to establish a methodology to predict thermal barrier coating (TBC) life on gas turbine engine components. The approach involved experimental life measurement coupled with analytical modeling of relevant degradation modes. Evaluation of experimental and flight service components indicate the predominant failure mode to be thermomechanical spallation of the ceramic coating layer resulting from propagation of a dominant near interface crack. Examination of fractionally exposed specimens indicated that dominant crack formation results from progressive structural damage in the form of subcritical microcrack link-up. Tests conducted to isolate important life drivers have shown MCrAlY oxidation to significantly affect the rate of damage accumulation. Mechanical property testing has shown the plasma deposited ceramic to exhibit a non-linear stress-strain response, creep and fatigue. The fatigue based life prediction model developed accounts for the unusual ceramic behavior and also incorporates an experimentally determined oxide rate model. The model predicts the growth of this oxide scale to influence the intensity of the mechanic driving force, resulting from cyclic strains and stresses caused by thermally induced and externally imposed mechanical loads

Effects of mineral admixtures on some properties of crude oil polluted sand

Bu tez, ham petrol ile kirlenmiş bir alanda çevre kirliliği üzerine bir çalışma sunmaktadır. Ayrıca, tez çalışmasında öğütülmüş granül yüksek fırın cürufu (GGBFS) ve uçucu kül (FA) gibi mineral katkılar kirlenmiş zemini stabilize etmek için kullanılmıştır. Bu çalışmanın temel amacı ise, ham petrol ile kirlenmiş zemini geliştirmek için mineral katkıların değerlendirilmesidir. Çalışma, Lajan köyüne yakın Erbil-Gwear anayol lokasyonu üzerine odaklanmıştır. Bu alanda birkaç rafineri istasyonu bulunduğundan, çevre konularını incelemek de oldukça önem arz etmektedir. Kumlu zeminlerin bazı özellikleri üzerinde ham petrol kirlenmesinin etkilerinin gözlemlenebilmesi için, kumlu zemin numuneleri laboratuvar ortamında kuru ağırlıkça %0, %2, %4, %6, %8, %10, %12, %14 ve %16 ham petrol içerecek şekilde ham petrol ile karıştırılmıştır. Ayrıca, mineral katkıların etkilerinin değerlendirilmesi için, ham petrol ile kirlenmiş zemin numuneleri ve mineral katkılar farklı oranlarda karıştırılarak çeşitli karışımlar hazırlanmıştır. Örneğin, bu çalışmada kirlenmiş zeminler %0, %4, %6 ve %8 oranlarında GGBFS ile ve %0, %10 ve %15 oranlarında FA ile karıştırılmıştır. Bu çalışmada sıkıştırma ve basit kesme testleri kullanılmıştır. Bu araştırmanın sonuçları, ham petrol yüzdesi arttığında özgül ağırlık, optimum nem içeriği ve maksimum kuru yoğunluğun azaldığını göstermektedir. Sürtünme açısı sonuçları ise artan ham petrol yüzdesine bağlı olarak dalgalanmıştır. Görünen kohezyon (c) değerleri ise belirli bir noktaya kadar artmış, daha sonra ham petrol yüzdesinin artmasına bağlı olarak az miktarda azalmıştır. Bununla birlikte mineral katkıların kullanılması da, kirlenmiş zeminin sıkıştırma ve dayanma özelliklerinde iyileşme sağlamıştır. Ayrıca, çalışmada kullanılan her bir faktörün farklılıkların öneminin gösterilmesi için istatistiksel analiz yapılmıştır

A History of Materials and Technologies Development

The purpose of the book is to provide the students with the text that presents an introductory knowledge about the development of materials and technologies and includes the most commonly available information on human development. The idea of the publication has been generated referring to the materials taken from the organic and non-organic evolution of nature. The suggested texts might be found a purposeful tool for the University students proceeding with studying engineering due to the fact that all subjects in this particular field more or less have to cover the history and development of the studied object. It is expected that studying different materials and technologies will help the students with a better understanding of driving forces, positive and negative consequences of technological development, etc

Energy: A continuing bibliography with indexes, issue 34

This bibliography lists 1015 reports, articles, and other documents introduced into the NASA scientific and technical information system from April 1, 1981 through June 30, 1981

NASA Tech Briefs, September 1988

Topics include: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

Geothermal program review 16: Proceedings. A strategic plan for geothermal research

The proceedings contain 21 papers arranged under the following topical sections: Exploration technology (4 papers); Reservoir technology (5 papers); Energy conversion technology (8 papers); Drilling technology (2 papers); and Direct use and geothermal heat pump technology (2 papers). An additional section contains a report on a workshop on dual-use technologies for hydrothermal and advanced geothermal reservoirs

Computational Modelling of Concrete and Concrete Structures

Computational Modelling of Concrete and Concrete Structures contains the contributions to the EURO-C 2022 conference (Vienna, Austria, 23-26 May 2022). The papers review and discuss research advancements and assess the applicability and robustness of methods and models for the analysis and design of concrete, fibre-reinforced and prestressed concrete structures, as well as masonry structures. Recent developments include methods of machine learning, novel discretisation methods, probabilistic models, and consideration of a growing number of micro-structural aspects in multi-scale and multi-physics settings. In addition, trends towards the material scale with new fibres and 3D printable concretes, and life-cycle oriented models for ageing and durability of existing and new concrete infrastructure are clearly visible. Overall computational robustness of numerical predictions and mathematical rigour have further increased, accompanied by careful model validation based on respective experimental programmes. The book will serve as an important reference for both academics and professionals, stimulating new research directions in the field of computational modelling of concrete and its application to the analysis of concrete structures. EURO-C 2022 is the eighth edition of the EURO-C conference series after Innsbruck 1994, Bad Gastein 1998, St. Johann im Pongau 2003, Mayrhofen 2006, Schladming 2010, St. Anton am Arlberg 2014, and Bad Hofgastein 2018. The overarching focus of the conferences is on computational methods and numerical models for the analysis of concrete and concrete structures