Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “ultrasonic”

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 649 records · Page 36
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Low Energy Ultrasonic Separation

Separations exist in all manufacturing sectors, accounting for 22% of in-plant energy use. Whereas energy-intense technologies such as centrifuges are well established, low energy separations account for only 1% of industrial energy consumption. Researchers at Los Alamos National Lab are developing a low energy ultrasonic particle concentrator for industry. This technology may reduce energy use, improve separations, reduce wastes, and cut manufacturing costs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2021

Model-Based Ultrasonic Signal Processing for the Nondestructive Evaluation of Additive Manufacturing Components

Ultrasonic testing (UT) for nondestructive evaluation (NDE) is a critical entity necessary to resolve both the quality and precision questions of complex parts evolving from the innovative additive manufacturing (AM) process. This modality provides the essential quantitative information for acceptance and potential flaw detectionof the part under investigation. A primary ingredient in UT besides the required precision robotic hardware for theacquisition of high quality measurement data is the underlying signal processing. It is here that much of the system performance capability resides. In this report,we discuss the basic steps in UT signal processing along with current and future capabilities that must be achieved in order to satisfy the critical demands created by the AM process.

42 ENGINEERING↗
DOE OSTI2021

In Situ Synchrotron Tensile Investigations on Ultrasonic Additive Manufactured (UAM) Zirconium

The microstructure evolution of ultrasonic additive manufactured (UAM) zirconium under room temperature uniaxial tensile straining is reported. Miniature dog-bone tensile specimens of two orientations were cut from a UAM zirconium bar for in situ synchrotron tensile tests. Wide-angle X-ray scattering (WAXS) scanning at the Advanced Photon Source (APS) at Argonne National Laboratory was used to unveil the changes in microstructure of the entire gauge regions throughout the straining. A series of WAXS data analysis methods were utilized to quantify both elastic and plastic deformation mechanisms within the strained specimens. Stress concentrations were identified during early stage of plastic deformation, which become candidate necking positions and eventually lead to failure. Fracture surface analysis implied that these stress concentration locations may be correlated to the fabrication defects, providing insightful guidance for future improvement of the UAM zirconium process.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Ultrasonic Jet Bat Deterrent System Advancement

General Electric Renewable Energy (GE) and the Department of Energy (DOE) worked to develop a project with an objective to increase confidence in acoustic ultrasonic bat deterrent technologies in wind turbines, by mitigating stakeholder investment risks that currently hinder the adoption of deterrent technologies. Many wind turbine sites utilize a bat conservation plan that curtail wind turbines and stop energy production. Curtailment is a known bat impact mitigation solution that has an history of environmental regulatory acceptance. To help support a solution that allows for simultaneous bat conservation and energy production with regulatory acceptance of acoustic bat deterrents, GE proposed a study to compare four treatments: control (no curtailment or deterrent), deterrent only, deterrent plus curtailment, and curtailment only. The concept was to provide a direct comparison of bat deterrent and curtailment effectiveness within the same wind farm and bat migration season. This comparison was intended to advocate for the adoption of bat deterrents with a large-scale field study by addressing customer concerns on regulatory acceptance of deterrents. The study was to be hosted at a forested habitat site during a bat migration season, by Stony Creek Energy, LLC (SCE), the owner of the Orangeville Wind Farm (OWF) in the state of New York. Included was a behavioral study plan with two turbines to monitor bat flight paths with thermal imaging cameras.

17 WIND ENERGY↗
DOE OSTI2025

Sound Speeds of Solids from Ultrasonic Pulse Receiver Measurements

A common method of determining elastic material properties is utilizing an ultrasonic pulse receiver. This is a non-destructive test (NDT) causing no plastic deformation of the material. It requires a pulse generator, oscilloscope, and two transducers to measure the sound velocity of a material. Both longitudinal and shear sound velocities may be obtained by utilizing the appropriate transducer. Acoustic nondestructive testing methods are often used in manufacturing certification processes and for material defect detection in industry. These methods can also be utilized to directly measure the elastic moduli of a material without damaging the material. Overall, it is a low-cost experiment with minimal preparation, and is easy to use.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Study of Elastic and Structural Properties of BaFe2As2 Ultrathin Film Using Picosecond Ultrasonics

We obtain the through-thickness elastic stiffness coefficient (C33) in nominal 9 nm and 60 nm BaFe2As2 (Ba-122) thin films by using picosecond ultrasonics. Particularly, we reveal the increase in elastic stiffness as film thickness decreases from bulk value down to 9 nm, which we attribute to the increase in intrinsic strain near the film-substrate interface. Our density functional theory (DFT) calculations reproduce the observed acoustic oscillation frequencies well. In addition, temperature dependence of longitudinal acoustic (LA) phonon mode frequency for 9 nm Ba-122 thin film is reported. The frequency change is attributed to the change in Ba-122 orthorhombicity (a−b)/(a+b). This conclusion can be corroborated by our previous ultrafast ellipticity measurements in 9 nm Ba-122 thin film, which exhibit strong temperature dependence and indicate the structural phase transition temperature Ts.

36 MATERIALS SCIENCE↗
DOE OSTI2020

In Situ and Post-Mortem Characterizations of Ultrasonic Spot Welded AZ31B and Coated Dual Phase 590 Steel Joints

Ultrasonic spot welding using different welding conditions was applied to join dissimilar metals of galvanized DP590 steel and AZ31B magnesium sheets. In situ high-speed imaging, digital image correlation, and infrared thermography were utilized to quantitatively study the interfacial relative motion, surface indentation, and heat generation across the joint faying interface and the sheet/sonotrode interfaces under the welding condition of moderate welding power and short welding time. For welds made with high power and long welding time, lap shear tensile tests as well as fatigue tests were carried out. Different fracture modes were observed after the lap shear tensile tests and fatigue tests performed under different peak loads. Post-weld cross-sectional analysis with scanning electron microscopy coupled with energy dispersive X-Ray spectroscopy revealed the variation of morphology and chemical composition at the joint interface for welds made with different welding conditions.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Characterization of CNC Nanoparticles Prepared via Ultrasonic-Assisted Spray Drying and Their Application in Composite Films

The ultrasonic-assisted spray dryer, also known as a nano spray dryer and predominantly used on a lab scale in the pharmaceutical and food industries, enables the production of nanometer-sized particles. In this study, the nano spray dryer was applied to cellulosic materials, such as cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs). CNC suspensions were successfully dried, while the CNF suspensions could not be dried, attributable to their longer fibril lengths. The nano spray drying process was performed under different drying conditions, including nebulizer hole sizes, solid concentrations, and gas flow rates. It was confirmed that the individual particle size of nano spray-dried CNCs (nano SDCNCs) decreased as the nebulizer hole sizes and solid contents of the suspensions decreased. The production rate of the nano spray dryer increased with higher solid contents and lower gas flow rates. The resulting nano SDCNCs were added to a polyvinyl alcohol (PVA) matrix as a reinforcing material to evaluate their reinforcement behavior in a plastic matrix using solvent casting. After incorporating the 20 wt.% nano SDCNCs into the PVA matrix, the tensile strength and tensile modulus elasticity of the neat PVA nanocomposite film increased by 22% and 32%, respectively, while preserving the transparency of the films.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Synthesis and Characterization of Copolymers and Nanocomposites from Limonene, Styrene and Organomodified-Clay Using Ultrasonic Assisted Method

In the present work, we report a simple synthesis method for preparation of copolymers and nanocomposites from limonene and styrene using clay as a catalyst. The copolymerization reaction is carried out by using a proton exchanged clay as a catalyst called Mag-H+. The effect of temperature, reaction time and amount of catalyst were studied, and the obtained copolymer structure (lim-co-sty) is characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H-NMR) and differential scanning calorimetry (DSC). The molecular weight of the obtained copolymer is determined by gel permeation chromatography (GPC) and is about 4500 g·mol−1. The (lim-co-sty/Mag 1%, 3%, 7% and 10% by weight of clay) nanocomposites were prepared through polymer/clay mixture in solution method using ultrasonic irradiation, in the presence of Mag-CTA+ as green nano-reinforcing filler. The Mag-CTA+ is organophilic silicate clay prepared through a direct exchange process, using cetyltrimethylammonuim bromide (CTAB). The prepared lim-co-sty/Mag nanocomposites have been extensively characterized by FT-IR spectroscopy, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM). TEM analysis confirms the results obtained by XRD and clearly show that the obtained nanocomposites are partially exfoliated for the lower amount of clay (1% and 3% wt) and intercalated for higher amounts of clay (7% and 10% wt). Moreover, thermogravimetric analysis (TGA) indicated an enhancement of thermal stability of nanocomposites compared with the pure copolymer.

Derdar, Hodhaifa↗
NASA NTRS1963

Ultrasonic Observation of the Calcite-Aragonite Transition

Elastic-wave velocities were measured as a function of pressure by ultrasonic pulse Interferometry in Solenhofen and Manilus limestone specimens to pressures of 27 and 38 kb. Longitudinal velocities decrease sharply from 5.3 km/sec at a mean pressure of 4 kb to a minimum of 4.8 km/sec at 8 kb. Transverse velocities decrease from 3.1 to 2.9 km/sec. At the minimum bulk and rigidity moduli are 25 and 20 per cent below their 4-kb values. A density increase of 1.7 per cent is associated with this minimum. The observed effects are attributed to the calcite-aragonite transition, and they may be due to an inherent property of the material, a component of which undergoes a polymorphic transition, the low- and high-pressure phases coexisting over a considerable pressure range. This may be an additional mechanism to account for low-velocity zones in the earth?s interior.

POLYMORPHISM↗
NASA NTRS1966

Ultrasonic recording scanner used for nondestructive weld inspection

Portable ultrasonic recording scanner is used for nondestructive inspection of welds. It is adaptable to continuous operation in one direction while maintaining oscillatory motion at a right angle to this direction. The scanning speed and oscillation frequency are independently adjustable.

Source record↗
NASA NTRS1966

Ultrasonic quality inspection of bonded honeycomb assemblies is automated

Inspection system for bonded honeycomb assemblies is accurate, fast, and automated. The ultrasonic system consists of inner and outer transducer positioning assemblies with suitable motor controls, a centerless turntable assembly, water squirter assemblies, and an inspection program completely encoded on tape suitable for use on a high speed computer.

Kammerer, C. C.↗
NASA NTRS1966

Ultrasonic water column probe speeds up testing of welds

Ultrasonic device consisting of a coaxial rod and transducer enclosed in a cylindrical probe which is filled with deionized or distilled water speeds up the testing of welds. Rubber diaphragm is molded to produce the desired test beam angle.

Hoop, J. M.↗