Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Engine Materials”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,243 records · Page 69

Building a Bright Future. The Hydro Research Foundation's Fellowship Program

The Hydro Fellowship Program (program) began as an experiment to discover whether the hydropower industry could find mechanisms to attract new entrants through conducting relevant research to benefit the industry. This nationwide, new-to-the-world program was started through funding from the Wind and Water Power Technologies Office of the Energy Efficiency and Renewable Energy (EERE) Office of the Department of Energy (DOE). Between 2010-2015, the Hydro Research Foundation (HRF) designed and implemented a program to conduct valuable research and attract new entrants to the hydro workforce. This historic grant has empowered and engaged industry members from 25 organizations by working with 91 students and advisors at 24 universities in 19 states. The work funded answered pressing research needs in the fields of civil, mechanical, environmental, and electrical engineering, as well as law, energy engineering and materials innovation. In terms of number of individuals touched through funding, 148 individuals were supported by this work through direct research, mentorship, oversight of the work, partnerships and the day-to-day program administration. Based on the program results, it is clear that the funding achieved the hoped-for outcomes and has the capacity to draw universities into the orbit of hydropower and continue the conversation about industry research and development needs. The Foundation has fostered unique partnerships at the host universities and has continued to thrive with the support of the universities, advisors, industry and the DOE. The Foundation has demonstrated industry support through mentorships, partnerships, underwriting the costs and articulating the universities’ support through in-kind cost sharing. The Foundation recommends that future work be continued to nurture these graduate level programs using the initial work and improvements in the successor program, the Research Awards Program, while stimulating engagement of academia at the community college level for operations and maintenance workforce development.

13 HYDRO ENERGY↗

Flaw Tolerance of Octet Truss Lattices with Random Flaws

We investigate the behavior of octet truss lattices in which some proportion of the bars are randomly removed from a perfect lattice. Using a lattice specimen of 9 × 9 × 9 octet truss unit cells as the nominal design, we simulate the response of prefect and flawed lattices with a finite element method implementation of rod theory. For each of two simple load cases, we perform a Monte Carlo analysis where we consider many instantiations of flawed lattices where between 1% and 20% of the bars are missing, and compare the axial loads in the remaining bars to those in the perfect lattice. We also compare the overall stiffness of the flawed lattices to the perfect lattice. Our results show progressive deterioration of lattice strength and stiffness with increasing proportion of missing bars, as expected, with the location and magnitude of the highest-loaded (most failure-prone) bars depending more on the load case and bar orientation than on the location and connectivity of missing bars. As such, the results reported herein may not be directly transferable to different lattice geometries.

36 MATERIALS SCIENCE↗

Final Report from Cal Poly on LLNL sponsored project

This final report consists of updates the project for the entire project period. The project started in 2018, ends on Sep 30th, 2020. Topics included are: Powder removal; Tensile Properties Test; Powder Flowability; and Thin walled Structure. Reports are included for each area.

36 MATERIALS SCIENCE↗

Evaluating Polymer Properties with Different Additives for Carbon Capture and Other Applications

Anthropogenic climate change is one of this generation’s most pressing concerns, with the potential to completely alter the delicate balance we’ve struck with nature. Already, global temperatures have risen 1.29°C, leading to disrupted weather systems, extinctions, increased risks of wildfires, and sea level rise, to name a few effects. Carbon dioxide emission from the combustion of fossil fuels and other industrial activity is a large driver of this phenomenon, as it absorbs heat before it can be radiated away from Earth, trapping it. Carbon dioxide has reached unprecedented levels in our atmosphere, showing a 50% increase from preindustrial averages to a whopping 430 ppm. Thus, reducing the amount of carbon dioxide via carbon capture technology is an important endeavor that serves to benefit everyone. The Microencapsulated CO 2 Sorbent (MECS) team at Lawrence Livermore National Laboratory (LLNL) has turned to microencapsulation to approach this endeavor. Microcapsules provide an attractive approach to carbon capture, combining large surface areas for more efficient mass transfer, regenerative abilities, reduced solvent loss, and improved handling. Additionally, while existing carbon capture technology relies on industrial plants, capsules could present a modular approach to carbon capture, reducing the need for extensive physical infrastructure. The MECS team’s design consists of a polymer membrane that contains a liquid carbon sequestering sorbent, aqueous sodium carbonate. The carbon capturing reaction occurs in three distinct steps, the first of which is the dissolution of carbon dioxide into the sorbent solution and its conversion into carbonic acid (H 2 CO 3 ), shown in equations 1 and 2 respectively. Because this step hinges upon the ability of carbon dioxide to reach the solution inside the capsule, it is necessary that the microcapsule shell is permeable to carbon dioxide gas. The MECS team produces these microcapsules using the in-air droplet encapsulation apparatus (IDEA) shown in figure 1, which can produce uniform micron-scale droplets at speeds much faster than traditional single-dispersal microfluidic-based techniques. The IDEA Is 100 times faster than these current techniques and can reach up to 1000 times their speed when incorporating a multi-nozzle design. Additionally, because droplets are produced in-air via vibration, IDEA can decrease post-processing times and material waste by 99% and can fabricate microgels that are 10 to 100 times more viscous than can be produced via traditional microfluidics. While this design represents a breakthrough in the throughput, efficiency, and tunability of microcapsule production, it imposes a major constraint on the microcapsule curing process. Because microcapsule shells are crosslinked with UV light while falling 30 cm through the air, this gives them a reaction window of approximately 0.2 seconds. Thus, the system and shell formulations must be optimized such that the shells can be fully crosslinked within this very narrow window, prompting investigations into curing behavior.

36 MATERIALS SCIENCE↗

Trends in high temperature materials technology for advanced aircraft turbine engines

The utilization of high temperature materials for turbine blades, disks, vanes, and combustors is reviewed. The use of directionally solidified eutectic alloys and of metal fiber reinforced superalloys as turbine blade materials is discussed. The application of powder metallurgy to the production of turbine disks is considered. It is shown that oxide-dispersion strengthened alloys (including NiCr and NiCr-Al) and ceramics are the best refractory turbine vane materials. The use of heat resistant sheet alloys as combustor materials is examined. The cost benefits to be derived from the application of high temperature technology to advanced CTOL and STOL engines are described.

Blankenship, C. P.↗

Space Exploration: Oh, the Materials You'll Need!

Space exploration has many challenges and materials are critical for many of the systems required to enable robotic or human space exploration. This talk will highlight challenges for materials with an emphasis on thermal protection materials and systems. Solving the materials issues will require thinking about materials in the systems and environments where are they to be used. In many cases the materials must be designed for the application, and the system needs to be designed with the materials in mind. The talk will conclude with some thoughts on the skills needed for materials scientists and engineers working on materials for space.

Exploration↗

Space Exploration: Oh, the Materials You'll Need!

Space exploration has many challenges and materials are critical for many of the systems required to enable robotic or human space exploration. This talk will highlight challenges for materials with an emphasis on thermal protection materials and systems. Solving the materials issues will require thinking about materials in the systems and environments where are they to be used. In many cases the materials must be designed for the application, and the system needs to be designed with the materials in mind. The talk will conclude with some thoughts on the skills needed for materials scientists and engineers working on materials for space.

materials↗

Tool for Generation of MAC/GMC Representative Unit Cell for CMC/PMC Analysis

This document describes a recently developed analysis tool that enhances the resident capabilities of the Micromechanics Analysis Code with the Generalized Method of Cells (MAC/GMC) 4.0. This tool is especially useful in analyzing ceramic matrix composites (CMCs), where higher fidelity with improved accuracy of local response is needed. The tool, however, can be used for analyzing polymer matrix composites (PMCs) as well. MAC/GMC 4.0 is a composite material and laminate analysis software developed at NASA Glenn Research Center. The software package has been built around the concept of the generalized method of cells (GMC). The computer code is developed with a user friendly framework, along with a library of local inelastic, damage, and failure models. Further, application of simulated thermomechanical loading, generation of output results, and selection of architectures to represent the composite material have been automated to increase the user friendliness, as well as to make it more robust in terms of input preparation and code execution. Finally, classical lamination theory has been implemented within the software, wherein GMC is used to model the composite material response of each ply. Thus, the full range of GMC composite material capabilities is available for analysis of arbitrary laminate configurations as well. The primary focus of the current effort is to provide a graphical user interface (GUI) capability that generates a number of different user-defined repeating unit cells (RUCs). In addition, the code has provisions for generation of a MAC/GMC-compatible input text file that can be merged with any MAC/GMC input file tailored to analyze composite materials. Although the primary intention was to address the three different constituents and phases that are usually present in CMCs-namely, fibers, matrix, and interphase-it can be easily modified to address two-phase polymer matrix composite (PMC) materials where an interphase is absent. Currently, the tool capability includes generation of RUCs for square packing, hexagonal packing, and random fiber packing as well as RUCs based on actual composite micrographs. All these options have the fibers modeled as having a circular cross-sectional area. In addition, a simplified version of RUC is provided where the fibers are treated as having a square cross section and are distributed randomly. This RUC facilitates a speedy analysis using the higher fidelity version of GMC known as HFGMC. The first four mentioned options above support uniform subcell discretization. The last one has variable subcell sizes due to the primary intention of keeping the RUC size to a minimum to gain the speed ups using the higher fidelity version of MAC. The code is implemented within the MATLAB (The Mathworks, Inc., Natick, MA) developmental framework; however, a standalone application that does not need a priori MATLAB installation is also created with the aid of the MATLAB compiler.

Materials Engineering↗

Powertrain Materials: The Road to Higher Efficiencies

Advanced powertrain materials are critical for automakers to meet new fuel economy standards. Researchers at the Department of Energy’s Oak Ridge National Laboratory are working with industry to develop new propulsion materials that offer improved performance at lower costs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Improved biomass feedstock materials handling and feeding engineering data sets, design methods, and modeling/simulation tools

Forest Concepts led a project to develop a set of tools which enable feedstock handing equipment designers to better understand and model the flowability of bulk particulate biomass materials. The work products included improved flowability mathematical models, data sets used to populate the models, and two new laboratory devices – a biomass-scale true cubical triaxial tester and a biomass-scale gas pycnometer. This work was funded in part by the US Department of Energy under contact DE-EE0008254.

09 BIOMASS FUELS↗

Materials for Advanced Turbine Engines (MATE): Project 3: Design, fabrication and evaluation of an oxide dispersion strengthened sheet alloy combustor liner, volume 1

The suitability of wrought oxide dispersion strengthened (ODS) superalloy sheet for gas turbine engine combustor applications was evaluated. Incoloy MA 956 (FeCrAl base) and Haynes Developmental Alloy (HDA) 8077 (NiCrAl base) were evaluated. Preliminary tests showed both alloys to be potentially viable combustor materials, with neither alloy exhibiting a significant advantage over the other. Both alloys demonstrated a +167C (300 F) advantage of creep and oxidation resistance with no improvement in thermal fatigue capability compared to a current generation combustor alloy (Hastelloy X). MA956 alloy was selected for further demonstration because it exhibited better manufacturing reproducibility than HDA8077. Additional property tests were conducted on MA956. To accommodate the limited thermal fatigue capability of ODS alloys, two segmented, mechanically attached, low strain ODS combustor design concepts having predicted fatigue lives or = 10,000 engine cycles were identified. One of these was a relatively conventional louvered geometry, while the other involved a transpiration cooled configuration. A series of 10,000 cycle combustor rig tests on subscale MA956 and Hastelloy X combustor components showed no cracking, thereby confirming the beneficial effect of the segmented design on thermal fatigue capability. These tests also confirmed the superior oxidation and thermal distortion resistance of the ODS alloy. A hybrid PW2037 inner burner liner containing MA956 and Hastelloy X components was designed and constructed.

Henricks, R. J.↗

Fluidic Flow Assisted Deterministic Folding of Van der Waals Materials

Origami offers a distinct approach for designing and engineering new material structures and properties. The folding and stacking of atomically thin van der Waals (vdW) materials, for example, can lead to intriguing new physical properties including bandgap tuning, Van Hove singularity, and superconductivity. On the other hand, achieving well-controlled folding of vdW materials with high spatial precision has been extremely challenging and difficult to scale toward large areas. In this paper, a deterministic technique is reported to fold vdW materials at a defined position and direction using microfluidic forces. Electron beam lithography (EBL) is utilized to define the folding area, which allows precise control of the folding geometry, direction, and position beyond 100 nm resolution. Using this technique, single-atomic-layer vdW materials or their heterostructures can be folded without the need for any external supporting layers in the final folded structure. In addition, arrays of patterns can be folded across a large area using this technique and electronic devices that can reconfigure device functionalities through folding are also demonstrated. Such scalable formation of folded vdW material structures with high precision can lead to the creation of new atomic-scale materials and superlattices as well as opening the door to realizing foldable and reconfigurable electronics.

2D materials↗

Composite fan exit guide vanes for high bypass ratio gas turbine engines

Various composite materials were identified for reduced weight applications as fan exit guide vanes in high bypass ratio gas turbine engines. Candidate materials, airfoil geometry and ply orientation were evaluated using NASTRAN finite element analysis. A vane core and shell design approach utilizing several different fiber orientation concepts was selected and variations in bending and torsional stiffness were documented. Material suppliers and airfoil fabricators were selected to provide panels and airfoils which were inspected, environmentally conditioned and tested. Static and dynamic airfoil tests established durability characteristics for a range of composite material/design approaches.

Blecherman, S. S.↗

Materials and processes for Shuttle engine, external tank, and Solid Rocket Booster

The paper deals with the materials and processes for three Space Shuttle elements: Space Shuttle Main Engines (SSME), the External Tank (ET), and the Solid Rocket Boosters (SRB), beginning with an overview of the materials selection, tracking and control system. SSME materials and processes are considered with emphasis on hydrogen environment embrittlement, LOX/GOX compatibility, stress corrosion cracking, and hydraulic fluid testing and qualification. The ET is examined with attention given to welding and fracture mechanics, and the thermal protection system. The SRB is discussed with emphasis on corrosion prevention, stress corrosion and fracture toughness, the integrated test bed for in situ corrosion protection verification, aluminum processing, and the thermal protection system.

Schwinghamer, R. J.↗