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Impact of the mode of extraction on the lipidomic profile of oils obtained from selected amazonian palms

INFORM 2020年第4期31卷 24-30页

作者： Jaramillo, Juliana Erika Cristina Cardona Bautista, Marcela Piedad Carrillo Solano, Oscar Alberto Alvarez Achenie, Luke E. K. Barrios, Andrés Fernando González Department of Chemical Engineering Universidad de los Andes Bogotá Colombia Instituto Amazónico de Investigaciones Científicas Sinchi Bogotá Colombia Multiscale and Multiphysics Modeling Lab Department of Chemical Engineering Virginia Polytechnic Institute and State University United States

There is a growing tendency to include natural, often new, ingredients in mass consumer products. This is particularly true in the cosmetics and food industries, where these ingredients are used to continually improve and enhance their products to compete in a highly competitive market. However, the inclusion of these natural ingredients in product formulations is far from easy, because they are complex mixtures. More research is needed to gain a full understanding of their compositions before successful products containing these ingredients can be designed. © 2020, American Oil Chemists' Society. All rights reserved.

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modeling of the influence of a damaged thermally grown oxide (TGO) layer in an environmental barrier coating system 34

Modeling of the influence of a damaged thermally grown oxide...

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34th Technical Conference of the American Society for Composites, ASC 2019

作者： Mital, Subodh K. Ricks, Trenton M. Arnold, Steven M. Harder, Bryan J. University of Toledo ToledoOH43606 United States Multiscale and Multiphysics Modeling Branch NASA Glenn Research Center ClevelandOH44135 United States Environmental Effects and Coatings Branch NASA Glenn Research Center ClevelandOH44135 United States

ISBN: (纸本)9781605956022

Environmental barrier coatings (EBC) are an enabling technology for the successful application of ceramic matrix composites (CMCs) in air-breathing gas turbine engines. EBCs are susceptible to a number of failure modes including oxidation/delamination, recessions, chemical attack and dissolution, thermomechanical degradation, erosion, and foreign object impact damage in a combustion environment. Spallation of environmental barrier coating (EBC), induced by a thermally grown oxide (TGO) layer, is a key EBC failure mode. The TGO layer, resulting from steam oxidation, grows either from a silicon bond coat layer (if present) or from a silicon carbide (SiC) based substrate itself. The TGO layer evolves (i.e., thickness increases with time) as water vapor and oxygen gradually diffuse through the EBC, and the EBC spalls off once the TGO layer reaches some critical thickness. The critical thickness of the TGO layer for failure is in the range of 20-30 microns, but it can vary due to exposure temperature, microstructure etc. Current work at NASA Glenn Research Center, under the Revolutionary Tools and Methods (RTM) subproject is aimed at addressing associated failure modes in EBC systems and developing robust analysis tools to aid in the design/analysis of these systems. The objective of the current work is to conduct a sensitivity study to examine the influence of uniformly and non-uniformly grown oxide layers on the associated driving forces leading to spallation of the EBC when subjected to isothermal loading. The effect of damage in the TGO layer on the resulting stress states is also assessed both in uniform and non-uniform TGO layers. © 2019 by DEStech Publications, Inc. and American Society for Composites. All rights reserved.

关键词： Failure modes

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Coupled thermo-mechanical micromechanics modeling of the influence of thermally grown oxide layer in an environmental barrier coating system 33

Coupled thermo-mechanical micromechanics modeling of the inf...

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33rd Technical Conference of the American Society for Composites 2018

作者： Ricks, Trenton M. Arnold, Steven M. Harder, Bryan J. Multiscale and Multiphysics Modeling Branch NASA Glenn Research Center ClevelandOH44135 United States Environmental Effects and Coatings Branch NASA Glenn Research Center ClevelandOH44135 United States

ISBN: (纸本)9781510872073

Environmental Barrier Coatings (EBCs) have emerged as a promising means of protecting silicon based ceramic matrix composite (CMC) components for high temperature applications (e.g., aircraft engines). EBCs are often used to protect an underlying material (substrate) such as silicon carbide from extreme thermal/chemical environments. In a typical CMC/EBC system, an EBC may or may not be adhered to an underlying substrate with a bond coat (e.g., silicon). Irrespective, systems that utilize EBCs are susceptible to a number of failure modes including oxidation/delamination, recession, chemical attack and dissolution, thermomechanical degradation, erosion, and foreign object damage. Current work at NASA Glenn Research Center is aimed at addressing these failure modes in EBC systems and developing robust analysis tools to aid in the design process. The Higher-Order Theory for Functionally Graded Materials (HOTFGM), a precursor to the High-Fidelity Generalized Method of Cells micromechanics approach, was developed to investigate the coupled thermo-mechanical behavior of functionally graded composites and will be used herein to assess the development and growth of a low-stiffness thermally grown oxide (TGO) layer in EBC/CMC systems without a silicon bond coat. To accomplish this a sensitivity study is conducted to examine the influence of uniformly and nonuniformly grown oxide layer on the associated driving forces leading to mechanical failure (spallation) of EBC layer when subjected to isothermal loading. Copyright © (2018) by DEStech Publications, *** rights reserved.

关键词： Ceramic matrix composites

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Laser displacement measurements of fan blades in resonance and flutter during the boundary layer ingesting inlet and distortion-tolerant fan test

Laser displacement measurements of fan blades in resonance a...

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AIAA Aerospace Sciences Meeting, 2018

作者： Duffy, Kirsten P. Provenza, Andrew J. Bakhle, Milind A. Min, James B. Abdul-Aziz, Ali University of Toledo Department of Mechanical Industrial and Manufacturing Engineering ToledoOH43606 United States NASA Glenn Research Center Multiscale and Multiphysics Modeling Branch ClevelandOH44135 United States Kent State University College of Aeronautics and Engineering KentOH44240 United States

ISBN: (数字)9781624105241

ISBN: (纸本)9781624105241

NASA’s Advanced Air Transport Technology Project is investigating boundary layer ingesting propulsors for future subsonic commercial aircraft to improve aircraft efficiency, thereby reducing fuel burn. To that end, a boundary layer ingesting inlet and distortion-tolerant fan stage were designed, fabricated, and tested within the 8’x6’ Supersonic Wind Tunnel at NASA Glenn Research Center. Because of the distortion in the air flow ingested by the fan, the blades were designed to withstand a much higher aerodynamic forcing than for a typical clean flow. The blade response for several resonance modes was measured during start-up and shutdown, as well as at near 85% design speed. Flutter in the first bending mode was also observed in the fan at the design speed, at an off-design condition, although instabilities were difficult to instigate with this fan in general. Blade vibrations were monitored through twelve laser displacement probes that were placed around the inner circumference of the casing, at the blade leading and trailing edges. These probes captured the movement of all the blades during the entire test. In addition to blade vibration results, benefits and disadvantages of laser displacement probe measurements versus strain gage measurements are discussed. © 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Boundary layers

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Comparison of multiscale method of cells-based models for predicting elastic properties of filament wound C/C-SiC 32

Comparison of multiscale method of cells-based models for pr...

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32nd Technical Conference of the American Society for Composites 2017

作者： Pineda, Evan J. Fassin, Marek Bednarcyk, Brett A. Reese, Stefanie Simon, Jaan-Willem Multiscale and Multiphysics Modeling Branch NASA Glenn Research Center 21000 Brookpark Road MS 49/7 ClevelandOH44113 United States Institute of Applied Mechanics RWTH Aachen University Mies-van-der-Rohe-Str. 1 Aachen52074 Germany

ISBN: (纸本)9781510853065

Three different multiscale models, based on the method of cells (generalized and high fidelity) micromechanics models were developed and used to predict the elastic properties of C/C-SiC composites. In particular, the following multiscale modeling strategies were employed: Concurrent multiscale modeling of all phases using the generalized method of cells, synergistic (two-way coupling in space) multiscale modeling with the generalized method of cells, and hierarchical (one-way coupling in space) multiscale modeling with the high fidelity generalized method of cells. The three models are validated against data from a hierarchical multiscale finite element model in the literature for a repeating unit cell of C/C-SiC. Furthermore, the multiscale models are used in conjunction with classical lamination theory to predict the stiffness of C/C-SiC plates manufactured via a wet filament winding and liquid silicon infiltration process recently developed by the German Aerospace Institute. Copyright © (2017) by DEStech Publications, Inc. All rights reserved.

关键词： Filament winding

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Order-reduced solution of the nonlinear high-fidelity generalized method of cells micromechanics relations 32

Order-reduced solution of the nonlinear high-fidelity genera...

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32nd Technical Conference of the American Society for Composites 2017

作者： Ricks, Trenton M. Lacy, Thomas E. Pineda, Evan J. Bednarcyk, Brett A. Arnold, Steven M. Department of Aerospace Engineering Mississippi State University PO Box A Mississippi StateMS39762 United States Multiscale and Multiphysics Modeling Branch Materials and Structures Division NASA Glenn Research Center 21000 Brookpark Rd. MS 49-7 ClevelandOH44135 United States

ISBN: (纸本)9781510853065

The High-Fidelity Generalized Method of Cells (HFGMC) is one technique for accurately simulating nonlinear composite material behavior. The HFGMC uses a higher-order approximation for the subcell displacement field that allows for a more accurate determination of the subcell stress/strain fields at the cost of some computational efficiency. In order to reduce computational costs associated with the solution of the ensuing system of simultaneous equations, the HFGMC global system of equations for doubly-periodic repeating unit cells with nonlinear constituents was reduced in size through the use of a Petrov-Galerkin-based Proper Orthogonal Decomposition order-reduction scheme. A number of cases were presented that address the computational feasibility of using order-reduction techniques to solve solid mechanics problems involving complex microstructures. Copyright © (2017) by DEStech Publications, Inc. All rights reserved.

关键词： Computational efficiency

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A thermodynamically based work potential theory for predicting progressive damage and failure in 3D textile composites 17

A thermodynamically based work potential theory for predicti...

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17th European Conference on Composite Materials, ECCM 2016

作者： Huang, H. Sam Pineda, Evan J. Department of Mechanical Engineering State University of New York Stony BrookNY United States Multiscale and Multiphysics Modeling Branch NASA Glenn Research Center ClevelandOH United States

ISBN: (纸本)9783000533877

In this paper, a 3D thermodynamically-based work potential theory for modeling progressive damage for laminated, unidirectional composites,extend from 2D Schapery's theory, is used to predict the response of unidirectional composites under three point bending. An internal state variable, S, is defined to account for the dissipated energy due to damage evolution in the form of microstructural changes in the matrix. With the stationary of the total work potential with respect to the internal state variable, a thermodynamically-consistent set of evolution equations is derived. The internal state variable is related to the transverse and shear moduli through microdamage functions. The shear modulus and transverse modulus expressed as a function of internal state variable are obtained from coupon tests. The shear modulus and transverse modulus expressed as a function of internal state variable are implemented into 3D Schaperys theory to predict unidirectional composites under three point bending. The comparison of show good agreement between simulations and experiments under three point bending. © 2016, European Conference on Composite Materials, ECCM. All rights reserved.

关键词： Elastic moduli

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Information management workflow and tools enabling multiscale modeling within ICME paradigm 57

Information management workflow and tools enabling multiscal...

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57th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 2016

作者： Arnold, Steven M. Bednarcyk, Brett A. Austin, Nic Terentjev, Igor Cebon, Dave Marsden, Will Multiscale Modeling Structures and Materials Division NASA Glenn Research Center 21000 Brookpark Road ClevelandOH44135 United States Multiscale Modeling and Multiphysics Branch NASA Glenn Research Center 21000 Brookpark Road ClevelandOH44135 United States Software Division Granta Design Ltd. Rustat House 62 Clifton Road CambridgeCB1 7EG United Kingdom Granta Design Ltd. Rustat House 62 Clifton Road CambridgeCB1 7EG United Kingdom

ISBN: (数字)9781624103926

ISBN: (纸本)9781624103926

With the increased emphasis on reducing the cost and time to market of new materials, the need for analytical tools that enable the virtual design and optimization of materials throughout their processing - internal structure - property - performance envelope, along with the capturing and storing of the associated material and model information across its lifecycle, has become critical. This need is also fueled by the demands for higher efficiency in material testing;consistency, quality and traceability of data;product design;engineering analysis;as well as control of access to proprietary or sensitive information. Fortunately, material information management systems and physics-based multiscale modeling methods have kept pace with the growing user demands. Herein, recent efforts to establish workflow for and demonstrate a unique set of web application tools for linking NASA GRC’s Integrated Computational Materials Engineering (ICME) Granta MI® database schema and NASA GRC’s Integrated multiscale Micromechanics Analysis Code (ImMAC) software toolset are presented. The goal is to enable seamless coupling between both test data and simulation data, which is captured and tracked automatically within Granta MI®, with full model pedigree information. These tools, and this type of linkage, are foundational to realizing the full potential of ICME, in which materials processing, microstructure, properties, and performance are coupled to enable application-driven design and optimization of materials and structures. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Product design

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Experimental evaluation of an embedded boundary layer ingesting propulsor for highly efficient subsonic cruise aircraft 53

Experimental evaluation of an embedded boundary layer ingest...

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53rd AIAA/SAE/ASEE Joint Propulsion Conference, 2017

作者： Arend, David J. Wolter, John D. Hirt, Stefanie M. Provenza, Andrew J. Gazzaniga, John A. Cousins, William T. Hardin, Larry W. Sharma, Om P. NASA Glenn Research Center at Lewis Field Inlets and Nozzles Branch 21000 Brookpark Rd M.S. 5-12 ClevelandOH44135 United States United Technologies Research Center East HartfordCT06108 United States Multiscale and Multiphysics Modeling Branch 21000 Brookpark Rd M.S. 49-8 United States Acoustics Branch 21000 Brookpark Rd M.S. 49-8 United States Thermal and Fluid Sciences 411 Silver Lane United States Aerodynamics 411 Silver Lane United States Aerodynamics and Gas Turbines 411 Silver Lane United States

ISBN: (数字)9781624105111

ISBN: (纸本)9781624105111

Experimental tests have been completed of the performance and operability of a 0.289 scale Boundary Layer Ingesting (BLI) propulsor within the transonic test section of NASA's 8ft x6ft Supersonic Wind Tunnel (SWT). Utilizing its new 6.5ft x 6ft embedded propulsor testbed configuration, trials were completed of a multi-displinary, designed-integrated propulsor in a simulated upper aft Hybrid Wing Body (HWB) aircraft installation. This propulsor consisted of a Length-to-Diameter (L/D) ratio 0.66 inlet coupled with a 22 inch diameter, 1.34 Fan Stage Pressure Ratio (FSPR), 16 Bypass Ratio (BPR) distortion-tolerant turbofan stage. Data were acquired at the embedded propulsor's Mach 0.78 inflow Aerodynamic Design Point (ADP) operating conditions where it achieved a mass flow weighted inlet total pressure recovery and an adiabatic fan stage efficiency of 96.5% and 87.9%, respectively. This propulsor demonstrated a constant 100% corrected speed stability margin of approximately 12%. Tests were also conducted across the extents of its fan map from 70% through 105% corrected speed and from near choke operating conditions through its stability limit. These tests revealed that the propulsor's operation was generally well-behaved. Both steady state and high response inlet airflow distortion were measured in accordance with the Society of Automotive Engineers' (SAE) Aerospace Recommended Practice 1420. Application of Reynolds number scaling to the wind tunnel test results indicates that a full-scale aircraft equivalent fuel burn reduction of approximately 3.6% was achieved relative to the same aircraft and engine featuring a modern conventional fan in a strut mounted installation.

关键词： Boundary layers

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Overcoming the adoption barrier to electric flight 54

Overcoming the adoption barrier to electric flight

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54th AIAA Aerospace Sciences Meeting, 2016

作者： Borer, Nicholas K. Nickol, Craig L. Jones, Frank P. Yasky, Richard J. Woodham, Kurt Fell, Jared S. Litherland, Brandon L. Loyselle, Patricia L. Provenza, Andrew J. Kohlman, Lee W. Samuel, Aamod G. NASA Langley Research Center HamptonVA23681 United States NASA Glenn Research Center ClevelandOH44135 United States NASA Armstrong Flight Research Center EdwardsCA93523 United States Aeronautics Systems Analysis Branch MS 442 United States Operations and Engineering Branch MS 255A United States Safety Critical Avionics Branch MS 130 United States Aeronautics Systems Engineering Branch MS 238 United States Photovoltaic and Electrochemical Systems Branch MS 309-1 United States Multiscale and Multiphysics Modeling Branch MS 49-8 United States Rotating and Drive Systems Branch MS 49-8 United States

ISBN: (数字)9781624103933

ISBN: (纸本)9781624103933

Electrically-powered aircraft may enable dramatic increases in efficiency and reliability, reduced emissions, and reduced noise as compared to today’s combustion-powered aircraft. This paper describes a novel flight demonstration concept that will enable the benefits of electric propulsion, while keeping the convenience and utility of common fuels available at today’s airports. A critical gap in airborne electric propulsion research is addressed by accommodating adoption at the integrated aircraft-airport systems level, using a confluence of innovative but proven concepts and technologies in power generation and electricity storage that need to reside only on the airframe. Technical discriminators of this demonstrator include (1) a novel, high-efficiency power system that utilizes advanced solid oxide fuel cells originally developed for ultra-long-endurance aircraft, coupled with (2) a high-efficiency, high-power electric propulsion system selected from mature products to reduce technical risk, assembled into (3) a modern, high-performance demonstration platform to provide useful and compelling data, both for the targeted early adopters and the eventual commercial market. The proposed demonstrator concepts all meet or exceed the program goal of a 50% reduction in mission fuel cost compared to the unmodified aircraft. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All Rights Reserved.

关键词： Electric propulsion

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