Characterization of Ultrahigh-Performance Concrete Materials for Application in Modular Construction
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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.
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A description is given of an ultra-high vacuum surface-analysis chamber that incorporates an internal cell for performing atomic layer deposition at a pressure of up to ∼1 Torr. The apparatus permits the growth process to be interrupted in stages during which data can be obtained using infrared and x-ray photoemission spectroscopies together with other electron-based techniques. Demonstration results are given for the adsorption of H{sub 2}O on Si (100) at a pressure of ∼0.3 Torr. The system described is generally applicable in the study of any surface reaction under non-high-vacuum conditions in which there is a need for both infrared and electron spectroscopies.
When establishing the pedigree of a simulation tool, code verification is used to ensure that the implemented numerical algorithm is a faithful representation of its underlying mathematical model. During this process, numerical results on various meshes are systematically compared to a reference analytic solution. The selection of analytic solutions can be a laborious process, as it is difficult to establish adequate code confidence without performing redundant work. In this report we address this issue by applying a physics-based process that establishes a set of reference problems. In this process, code simulation options are categorized and systematically tested, which ensures that gaps in testing are easily identified and addressed. The resulting problems are primarily intended for code verification analysis but may also be useful for comparison to other simulation codes, troubleshooting activities, or training exercises. The process is used to select fifteen code verification problems relevant for the one-dimensional steady-state heat conduction equation. These problems are applicable to a wide variety of simulation tools, but, in this work, a demonstration is performed using the finite element-based nuclear fuel performance code BISON. Convergence to the analytic solution at the theoretical rate is quantified for a selection of the problems, which establishes a baseline pedigree for the code. Not only can this standard set of conduction solutions be used for verification of other codes, but also the physics-based process for selecting problems can be utilized to quantify and expand testing for any simulation tool.
A system of information codes for deterministic fractal lattices and sets of multifractal curves is proposed. An iterative modular design was used to obtain a series of deterministic fractal lattices with generators in the form of fragments of 2D structures and a series of multifractal curves (based on some Kepler-Shubnikov nets) having Cantor set properties. The main characteristics of fractal structures and their lacunar spectra are determined. A hierarchical principle is formulated for modules of regular fractal structures.
Site information, well schematics, component diagrams, and casing tally from the SECARB project at Cranfield oil site in Mississippi.
Case study of a DOE 2016 Housing Innovation Award winning multifamily home in the cold climate that met the DOE Zero Energy Ready Home criteria and achieved a HERS 42 without PV or HERS 5 with PV.
Case study of a DOE 2016 Housing Innovation Award winning production home in a cold climate that got a HERS -9 with PV, with 2x6 framed walls with spray foam cavity and rigid foam sheathing, a spray-foam insulated attic, a ground-source heat pump, and an HRV.
Computer program for near optimum structural designs of ring stiffened honeycomb sandwich nose fairings
An airship frame may be regarded as a rigid girder subjected to a number of forces which, according to their nature, may be classified as follows: weight or loads (force of gravity); lifting forces (aero-static); accelerations (dynamic). These forces must be in equilibrium in the three most important cases during flight: 1) when the airship is floating (aerostatic problem); 2) when flying without acceleration (aerodynamic problem). 3) When under the influence of any accelerating force (dynamic problem). This report will briefly discuss each of these cases in regard to the R-38 airship accident.
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The author describes experiments in designing nonrigid airships. A nonrigid airship of 32,000 cubic meters, the PL 27 withstood all stresses with 20 kg/m(exp 2) hull pressure during its life of two years. The moment of resistance is known, as also the stresses in the envelope for the given hull pressure. The mean internal pressure necessary to give the airship the requisite rigidity and to prevent buckling was also investigated.
The Commissariat of Aviation deems it expedient to issue a few rules of a general character which should be followed by constructors in designing aircraft, into the manufacture of which metal enters to a considerable extent. The materials covered include: aluminum, duralumin, soft steel, high-resistance steel, in sheets, tubing, and shaped elements.
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The use of duralumin by French airplane designers is presented, the results they have obtained, and their hopes for the future.
In the first article, in connection with a lecture on the hydrodynamic basis of flight and the potential flow about a Joukowski wing, the pressure distribution on several wings is computed and plotted. The diagrams of the pressure distributions are presented accompanied with a qualitative discussion of the pressure distribution. In the second article, the the cross-sectional outline (or profile) a Joukowski wing are plotted.
Different methods for increasing the efficiency of diesel engines are presented and some new designs are given.
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