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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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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Development and Assessment of a New Particle Image Velocimetry System in the NASA GRC 225 cm2 Wind Tunnel

As part of an ongoing campaign to provide detailed and thorough measurements in a two-dimensional impinging shock-wave/boundary-layer interaction (SWBLI), a custom implementation of the Particle Image Velocimetry (PIV) measurement technique in the NASA Glenn 225 cm2 Wind Tunnel was constructed. The flow seeding apparatus was devised to locally seed the region of interest in the overall flowfield to avoid coating the viewing window with seed material. The ability of the PIV system to provide small particles which faithfully track the underlying gas-phase flowfield was of key importance for the success of this system to make quality measurements in the SWBLI flowfield. In order to optimize and assess the performance of the particle seeding system, PIV measurements were made across a planar oblique shock wave and particle response was analyzed to quantify the particle lag effects due to the finite inertia of the seed droplets. Video recordings from a camera placed in the wind tunnel plenum tank were also used to discern the near-field behavior of the seeded plume and guide the design evolution of the seeding apparatus. The resulting optimized seeding configuration was applied to make PIV measurements in the wind tunnel test section boundary layer to assess the seed particle spatial coverage and concentration. This sample boundary layer dataset provides an analog to the eventual boundary layer measurements to be made in the axisymmetric test section under much more challenged viewing conditions.

PIV↗
NASA NTRS2001

Development of a Low-Cost, Subscale Test System to Evaluate Particle Impingement Erosion in Nozzle Ablative Materials

This viewgraph presentation gives an overview on the development of a low-cost, subscale test system to evaluate particle impingement erosion in nozzle ablative materials. Details are given on the need for a new test bed, solid fuel torch components, solid fuel torch test, additional uses for the solid fuel torch, the development of a supersonic blast tube (SSBT), and particle impingement material discrimination.

Lansing, Matthew D.↗
DOE OSTI2020

Experimental testing of particle attrition in CSP systems at high temperature

An alternate and sustainable form of energy is CSP systems, which capture and store the sun’s energy in the form of heat. Increasing the operational temperature of CSP systems will increase the efficiency of electricity production while operating at temperatures exceeding 700 degrees Celsius also creates novel operational problems. One approach for high-temperature CSP systems is to utilize solid particles as the primary heat transfer medium. As particles flow through this system, the movement of particles creates erosion in the forms of impact, abrasion, and attrition erosion. In the real world, while all three forms of erosion will occur simultaneously, it is imperative to understand the individual effect of each erosion over the lifetime of the powerplant. Besides material erosion and long-term durability concerns, thermal cycling of the particles could also introduce changes in particle thermal performance due to alterations in particle morphology. Current research on the issue of erosion has been limited to industrial applications and does not necessarily coincide with the operating conditions in CSP systems. We focus on attrition erosion resulting from particle-to-wall and particle-to-particle interactions. Research has shown that besides material hardness affecting how fast particles break down, attrition erosion increased as the size of the particles increased due to a higher chance of collision between the particles. Particle attrition is relevant to the CSP community as it may result in material loss, change the system's thermal performance, and generation of fines which could pose an environmental hazard. In this work, we focus on developing a test set up that can isolate and measure particle attrition when subjected to conditions relevant to Gen3 CSP systems.

14 SOLAR ENERGY↗
NASA NTRS1961

Absolute Definition of Phase Shift in the Elastic Scattering of a Particle from Compound Systems

The projection of the target wave function on the total wave function of a scattered particle interacting with the target system is used to define an absolute phase shift including any multiples of pi. With this definition of the absolute phase shift, one can prove rigorously in the limit of zero energy for s-wave electrons scattered from atomic hydrogen that the triplet phase shift must approach a nonzero multiple of pi. One can further show that at least one pi of this phase shift is not connected with the existence of a bound state of the H- ion.

Temkin, A.↗
DOE OSTI2019

Magnetic field falling particle solar receiver systems and methods

Systems and methods that increase the residence time of particles falling through a solar receiver using an induced magnetic field to suspend or slow down and/or alter the flight path of the particles falling through the concentrated beam of sunlight are disclosed.

14 SOLAR ENERGY↗
NASA NTRS1998

Particle Velocity Measuring System

Method and apparatus are provided for determining the velocity of individual food particles within a liquid/solid food mixture that is cooked by an aseptic cooking method whereby the food mixture is heated as it flows through a flowline. At least one upstream and at least one downstream microwave transducer are provided to determine the minimum possible travel time of the fastest food particle through the flowline. In one embodiment, the upstream detector is not required. In another embodiment, a plurality of small dipole antenna markers are secured to a plurality of food particles to provide a plurality of signals as the markers pass the upstream and downstream transducers. The dipole antenna markers may also include a non-linear element to reradiate a harmonic frequency of a transmitter frequency. Upstream and downstream transducers include dipole antennas that are matched to the impedance of the food slurry and a signal transmission cable by various impedance matching means including unbalanced feed to the antennas.

Arndt, G. Dickey↗
NASA NTRS1979

Radiation forces on small particles in the solar system

Solar radiation forces on small particles in the solar system are examined, and the resulting orbital evolution of interplanetary and circumplanetary dust is considered. An expression is derived for the effects of radiation pressure and Poynting-Robertson drag on small, spherical particles using the energy and momentum transformation laws of special relativity, and numerical examples are presented to illustrate that radiation pressure and Poynting-Robertson drag are only important for particles within a narrow size range. The orbital consequences of these radiation forces are considered both for heliocentric and planetocentric orbiting particles, and the coupling between particle sizes and dynamics is discussed. A qualitative derivation is presented for the differential Doppler effect, which is due to the differential Doppler shifting of radiation from approaching and receding solar hemispheres, and the Yarkovsky effect, which is important for rotating meter-to kilometer-sized particles, is briefly described.

Burns, J. A.↗
DOE OSTI2020

Falling particle impact erosion testing for particle based CSP systems

CSP systems are currently being examined as an effective method for using solar energy to generate electricity. While much of this research has been conducted using molten salt as the heat transfer medium, in recent years, solid particles have been posited as a cheaper and more energy efficient heat transfer medium for use in CSP systems. Many researchers have looked into the effectiveness of solid particles as a heat transfer medium. However, a concern with the use of particles is that the falling particles will impact various components within the CSP system, such as the hopper, the heat exchanger, and the insulating material, resulting in surface erosion and damage. With repeated impacts from falling particles, material from the surfaces under impact is removed. The degree of erosion depends on whether the substrate is made of brittle or ductile material. Furthermore, factors such as particle shape, size, hardness, concentration, impact angle, particle velocity, and substrate hardness will contribute to the erosion process and determine how much and how quickly erosion will takes place in a system. Three types of erosion will be observed simultaneously: impact erosion from particle impact on receiver, particle storage, and heat exchanger walls, abrasion erosion from particle sliding motion along walls, and attrition erosion as the particles breakdown from particle-to-particle contact and particle-to-wall interactions. It is imperative to understand each of these erosions individually for a more comprehensive understanding and prediction of CSP system durability. In this work, we developed an experimental test setup capable of measuring impact erosion at conditions relevant to 1MW CSP plant. Subsequently, Impact erosion measurements were performed for three different candidate substrate materials at low particle velocities using HSP 40/70 ceramic particles.

14 SOLAR ENERGY↗
NASA NTRS1973

A Comparison of the Measured Scattering Matrix Elements of Polydisperse Systems of Irregular Particles with the Matrix Elements Calculated for Spheres that Have the Same Distribution of Projected Areas

The elements of the scattering or Mueller Matrix for three polydisperse systems of irregular, randomly-oriented particles have been measured in absolute terms as a function of scattering angle for several visible wavelengths. The samples consisted of commercially available silicon dioxide particles that fit three distinct lognormal size distributions. The measured matrix elements were compared with the matrix elements calculated for spheres that had the same refractive index and fitted the same distribution of projected areas. Correlations and discrepancies between the two sets of matrix elements will be discussed.

Holland, A. C.↗
NASA NTRS2000

A New Digital Holographic Instrument for Measuring Microphysical Properties of Contrails in the SASS (Subsonic Assessment) Program

SPEC incorporated designed, built and operated a new instrument, called a pi-Nephelometer, on the NASA DC-8 for the SUCCESS field project. The pi-Nephelometer casts an image of a particle on a 400,000 pixel solid-state camera by freezing the motion of the particle using a 25 ns pulsed, high-power (60 W) laser diode. Unique optical imaging and particle detection systems precisely detect particles and define the depth-of-field so that at least one particle in the image is almost always in focus. A powerful image processing engine processes frames from the solid-state camera, identifies and records regions of interest (i.e. particle images) in real time. Images of ice crystals are displayed and recorded with 5 micron pixel resolution. In addition, a scattered light system simultaneously measures the scattering phase function of the imaged particle. The system consists of twenty-eight 1-mm optical fibers connected to microlenses bonded on the surface of avalanche photo diodes (APDs). Data collected with the pi-Nephelometer during the SUCCESS field project was reported in a special issue of Geophysical Research Letters. The pi-Nephelometer provided the basis for development of a commercial imaging probe, called the cloud particle imager (CPI), which has been installed on several research aircraft and used in More than a dozen field programs.

Lawson, R. Paul↗
NASA NTRS1969

Particle parameter analyzing system

An X-Y plotter circuit apparatus is described which displays an input pulse representing particle parameter information, that would ordinarily appear on the screen of an oscilloscope as a rectangular pulse, as a single dot positioned on the screen where the upper right hand corner of the input pulse would have appeared. If another event occurs, and it is desired to display this event, the apparatus is provided to replace the dot with a short horizontal line.

Hansen, D. O.↗
NASA NTRS1973

BEAMR: An interactive graphic computer program for design of charged particle beam transport systems

A computer program for a PDP-15 is presented which calculates, to first order, the characteristics of charged-particle beam as it is transported through a sequence of focusing and bending magnets. The maximum dimensions of the beam envelope normal to the transport system axis are continuously plotted on an oscilloscope as a function of distance along the axis. Provision is made to iterate the calculation by changing the types of magnets, their positions, and their field strengths. The program is especially useful for transport system design studies because of the ease and rapidity of altering parameters from panel switches. A typical calculation for a system with eight elements is completed in less than 10 seconds. An IBM 7094 version containing more-detailed printed output but no oscilloscope display is also presented.

Leonard, R. F.↗
DOE OSTI2020

Design analysis of a particle-based thermal energy storage system for concentrating solar power or grid energy storage

Energy storage is becoming indispensable for expanding renewable energy integration, and it is critical to the future low-carbon energy supply. Large-capacity, grid scale energy storage can support the integration of solar and wind power and support grid resilience with the diminishing capacity of baseload fossil power plants. With the development of thermal energy storage (TES) for concentrating solar power systems, standalone TES for grid integration becomes attractive due to the declining renewable generation cost and an increasing need for energy storage. The standalone TES system introduced in this paper can play a big role in the carbon-free energy future with capacity larger than batteries and cost likely lower than other energy storage methods such as pumped storage hydropower and compressed air energy storage, both of which also have geological limitations. To this end, we describe a TES system that uses stable, inexpensive solid particles as a TES media to provide scalable, low cost energy storage. The particle-based TES has the ability to drive various thermal power cycles including conventional steam-Rankine, air Brayton turbine with combined-cycle ability, or the emerging supercritical carbon dioxide Brayton power cycle. This work describes the containment design method including a concrete silo and an internal-insulation layer for the particle-TES system. The economic analysis shows significantly low storage cost when the particle-TES is integrated with Brayton combined-cycle power generation. The paper shows the design approach of the particle-TES system and its economic potential for bulk energy storage. The advantage of the particle-TES system as a promising bulk energy storage method is its ability to economically support dispatchable renewable grid penetration for larger capacity and longer discharging hours than current battery storage technologies.

25 ENERGY STORAGE↗
DOE OSTI2022

Methods and systems for producing nanolipoprotein particles

Provided herein are methods and systems for the production of a nanolipoprotein particle (NLP) that includes a scaffold protein a membrane forming lipid and optionally a target protein. At least one of the scaffold protein and target protein can be provided through an IVT system. The membrane forming lipid, scaffold protein and optionally the target protein can be assembled for a time and under conditions that allow obtaining high yield NLPs, NPLs with an increased solubility, an NLP of a controlled size, and/or an NLP having a size predetermined to include a pre-selected target protein.

Coleman, Matthew A.↗