SEARCH · Engineering Papers

Results for “materials flows through industry”

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.

SourceResearch connectionFrom yearThrough year

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

At least 19 records

All sources NASA NTRS DOE OSTI

NASA NTRS1956

Friction factors for flow of non-newtonian materials in pipelines

In many industries, non-Newtonian material, such as oils, lubricants, foods, cosmetics, and solid-liquid suspensions, are passed through pipelines during manufacture, application, or transportation. For the proper design of the pipelines, and evaluation of the flow resistance of the materials when flowing in these pipelines is essential. The pressure loss Δ p , due to a material flowing through a straight pipeline can be expressed as a function of a friction factor, φ, so that Δ p = ( pv 2 )/2 L/D φ where φ is a function of the flow properties of the material v is the mean velocity of the material and can be determined from the mas-flow rate, L is the length and D is the diameters of the pipeline, and p is the density of the material. The purpose of this paper is to present a generalized friction diagram, which can be used to determine φ for any material and flow condition, provided the flow properties of the material and the mean flow velocity in the pipeline are known. In composing this diagram generous use is made of the literature and only parts of the diagram and the presentation can claim originality.

Ruth N Weltmann↗

NASA NTRSDate not supplied

Packing and flow particle simulations

Granular material is present across natural and industrial processes on Earth and other planets. Granular particles show up in space exploration (lunar regolith), avalanches (boulders), food (coffee), construction (concrete powder) and manufacturing (additive manufacturing powder, battery slurries). Important phenomena emerge from large collections of granular particles. The size scales of the particles in granular material, 10 μm diameter or larger, makes particle-based simulations a tractable computational method. This seminar will present the packing and flow of granular matter using particle-based discrete element modeling simulations. Particles modeled with rotational friction only require as few as 2.6 contacts for mechanical stability, as opposed to 6 contacts for frictionless particles. Optimal parameters for in-space manufacturing particulate material are identified. Specifically, the maximum density and contacts occurs for a large-to-small particle volume ratio of 0.265. Stress and contact fabric fluctuations of flowing dry granular matter have power-law scaling with strain rate, and a kink. The pressure-dependent slope change kink could identify the transition between slower, quasistatic and faster, inertial flows.

granular↗

NASA NTRSDate not supplied

Packing and flow particle simulations

granular↗

NASA NTRS1998

LSPRAY: Lagrangian Spray Solver for Applications With Parallel Computing and Unstructured Gas-Phase Flow Solvers

Sprays occur in a wide variety of industrial and power applications and in the processing of materials. A liquid spray is a phase flow with a gas as the continuous phase and a liquid as the dispersed phase (in the form of droplets or ligaments). Interactions between the two phases, which are coupled through exchanges of mass, momentum, and energy, can occur in different ways at different times and locations involving various thermal, mass, and fluid dynamic factors. An understanding of the flow, combustion, and thermal properties of a rapidly vaporizing spray requires careful modeling of the rate-controlling processes associated with the spray's turbulent transport, mixing, chemical kinetics, evaporation, and spreading rates, as well as other phenomena. In an attempt to advance the state-of-the-art in multidimensional numerical methods, we at the NASA Lewis Research Center extended our previous work on sprays to unstructured grids and parallel computing. LSPRAY, which was developed by M.S. Raju of Nyma, Inc., is designed to be massively parallel and could easily be coupled with any existing gas-phase flow and/or Monte Carlo probability density function (PDF) solver. The LSPRAY solver accommodates the use of an unstructured mesh with mixed triangular, quadrilateral, and/or tetrahedral elements in the gas-phase solvers. It is used specifically for fuel sprays within gas turbine combustors, but it has many other uses. The spray model used in LSPRAY provided favorable results when applied to stratified-charge rotary combustion (Wankel) engines and several other confined and unconfined spray flames. The source code will be available with the National Combustion Code (NCC) as a complete package.

Raju, Manthena S.↗

NASA NTRS2002

Spray and High-Pressure Flow Computations in the National Combustion Code (NCC) Improved

Sprays occur in a wide variety of industrial and power applications and in materials processing. A liquid spray is a two-phase flow with a gas as the continuous phase and a liquid as the dispersed phase in the form of droplets or ligaments. The interactions between the two phases--which are coupled through exchanges of mass, momentum, and energy--can occur in different ways at disparate time and length scales involving various thermal, mass, and fluid dynamic factors. An understanding of the flow, combustion, and thermal properties of a rapidly vaporizing spray requires careful modeling of the ratecontrolling processes associated with turbulent transport, mixing, chemical kinetics, evaporation, and spreading rates of the spray, among many other factors. With the aim of developing an efficient solution procedure for use in multidimensional combustor modeling, researchers at the NASA Glenn Research Center have advanced the state-of-the-art in spray computations in several important ways.

Raju, Manthena S.↗

NASA NTRS1994

Image-Processing Program

IMAGEP manipulates digital image data to effect various processing, analysis, and enhancement functions. It is keyboard-driven program organized into nine subroutines. Within subroutines are sub-subroutines also selected via keyboard. Algorithm has possible scientific, industrial, and biomedical applications in study of flows in materials, analysis of steels and ores, and pathology, respectively.

Roth, D. J.↗

NASA NTRS1979

Resonance-tube ignition of aluminum

An experimental program was carried out to determine whether spontaneous fluid-dynamic oscillations could create a hazard in gaseous oxygen flow systems by igniting metal contaminants. The particular fluid-dynamic oscillation studied was the resonance-tube phenomenon as it was excited in a tee-shaped configuration representative of configurations found in many industrial flow systems. Pure aluminum was chosen as the candidate material for ignition. The oscillations in the tee-shaped configuration were compared with oscillations driven by choked convergent nozzles and were found to differ markedly. The temperatures generated at the base of the resonance tube were well in excess of 1000 F for both gaseous oxygen and nitrogen. The effect of inert particulate matter introduced into the resonance tube was to increase significantly the measured temperatures. Aluminum in both powder and fiber form was readily ignited within the resonance tube at pressures less than 1200 psia. At higher pressures, the aluminum-oxygen mixture exploded. This investigation confirms the hazardous nature of resonance-tube oscillations as generated in typical piping configurations that use high-pressure oxygen.

Phillips, B. R.↗

NASA NTRS1980

A feasibility study for advanced technology integration for general aviation

An investigation was conducted to identify candidate technologies and specific developments which offer greatest promise for improving safety, fuel efficiency, performance, and utility of general aviation airplanes. Interviews were conducted with general aviation airframe and systems manufacturers and NASA research centers. The following technologies were evaluated for use in airplane design tradeoff studies conducted during the study: avionics, aerodynamics, configurations, structures, flight controls, and propulsion. Based on industry interviews and design tradeoff studies, several recommendations were made for further high payoff research. The most attractive technologies for use by the general aviation industry appear to be advanced engines, composite materials, natural laminar flow airfoils, and advanced integrated avionics systems. The integration of these technologies in airplane design can yield significant increases in speeds, ranges, and payloads over present aircraft with 40 percent to 50 percent reductions in fuel used.

Kohlman, D. L.↗

NASA NTRS1957

The Effect of Solid Admixtures on the Velocity of Motion of a Free Dusty Air Jet

In dusty air flows occurring in industrial practice in transport by air pressure of friable materials, in the drying, annealing, and so forth, of a pulverized solid mass in suspension, and in other processes, the concentration of solid particles usually has a magnitude of the order of 1 kg per 1 kg of air. At such a concentration, the ratio of the volume of the particles to the volume of the air is small (less than one-thousandth part). However, regardless of this, the presence of a solid admixture manifests itself in the rules for the velocity distribution of the air in a dusty air flow. As a result, the rules of velocity change are different for clean and for dusty air flows. The estimation of the influence of the admixture on the velocity of the motion of the flow presents a definitive interest. One of the attempts to estimate that influence on the axial velocity of a free axially symmetrical jet with admixtures was made by Abramovich. Abramovich assumed beforehand that the fine particles of the admixture in the jet are subject to the motion of the air (that is, that the velocity of the admixture is approximately equal to the local velocity of the air); he then took as the basis of his considerations, in solving the problem, the condition that the amount of motion of the two-phase jet must be constant.

Chernov, A. P.↗

NASA NTRS2002

Studies of Gas-Particle Interactions in a Microgravity Flow Cell

The ability to transport particulate materials predictably and efficiently using a flowing gas is likely to play an important role in the development of lunar and Martian environments that are hospitable to humans. Lunar soil contains significant amounts of oxygen, hydrogen and other critical materials that are chemically bound in various minerals. Through appropriate processing, these resources may be recovered for use in propulsion, life support systems and mining operations. Similarly, it is believed that Martian soil contains significant amounts of water which can be electrolyzed into oxygen and hydrogen, again for propellants and life support. The transport of such granular soils from where they are mined and between stages of their processing is likely to involve pneumatic transport carried out in systems of pipes using flows of the liberated gases. On earth, the transport and processing of solid materials are also crucial in a number of applications from the chemical, mining, power and oil industries. For these flows, an appreciation has recently developed for the influence of collisional interactions among particles, both in suspensions where the flow is laminar and turbulent. Collisions between such particles can transfer a significant amount of momentum within the flow and at the boundaries. This provides an additional resistance to the passage of the gas, but it also introduces a mechanism that promotes more homogeneous flows and, at least in small-diameter pipes, may forestall the development of clusters.

Louge, Michel Y.↗

NASA NTRS1984

Fundamentals of Alloy Solidification Applied to Industrial Processes

Solidification processes and phenomena, segregation, porosity, gravity effects, fluid flow, undercooling, as well as processing of materials in the microgravity environment of space, now available on space shuttle flights were discussed.

Source record↗

NASA NTRS1985

Autoclave processing for composite material fabrication. 1: An analysis of resin flows and fiber compactions for thin laminate

High quality long fiber reinforced composites, such as those used in aerospace and industrial applications, are commonly processed in autoclaves. An adequate resin flow model for the entire system (laminate/bleeder/breather), which provides a description of the time-dependent laminate consolidation process, is useful in predicting the loss of resin, heat transfer characteristics, fiber volume fraction and part dimension, etc., under a specified set of processing conditions. This could be accomplished by properly analyzing the flow patterns and pressure profiles inside the laminate during processing. A newly formulated resin flow model for composite prepreg lamination process is reported. This model considers viscous resin flows in both directions perpendicular and parallel to the composite plane. In the horizontal direction, a squeezing flow between two nonporous parallel plates is analyzed, while in the vertical direction, a poiseuille type pressure flow through porous media is assumed. Proper force and mass balances have been made and solved for the whole system. The effects of fiber-fiber interactions during lamination are included as well. The unique features of this analysis are: (1) the pressure gradient inside the laminate is assumed to be generated from squeezing action between two adjacent approaching fiber layers, and (2) the behavior of fiber bundles is simulated by a Finitely Extendable Nonlinear Elastic (FENE) spring.

Hou, T. H.↗

NASA NTRS1975

Ispra Mark-10 water splitting process

A thermochemical water splitting process, the Ispra Mark-10 chemical reaction cycle, was chosen for examining the possibility of using water to produce hydrogen on a large scale for fuel and major industrial chemical uses. The assumed energy source for the process is an HTGR (helium cooled). A process flow diagram, a material balance, and an energy balance were developed for the thermochemical reaction cycle. Principal reactions which constitute the cycle are included.

Source record↗

NASA NTRS1986

Materials Research Capabilities

Lewis Research Center, in partnership with U.S. industry and academia, has long been a major force in developing advanced aerospace propulsion and power systems. One key aspect that made many of these systems possible has been the availability of high-performance, reliable, and long-life materials. To assure a continuing flow of new materials and processing concepts, basic understanding to guide such innovation, and technological support for development of major NASA systems, Lewis has supported a strong in-house materials research activity. Our researchers have discovered new alloys, polymers, metallic composites, ceramics, coatings, processing techniques, etc., which are now also in use by U.S. industry. This brochure highlights selected past accomplishments of our materials research and technology staff. It also provides many examples of the facilities available with which we can conduct materials research. The nation is now beginning to consider integrating technology for high-performance supersonic/hypersonic aircraft, nuclear space power systems, a space station, and new research areas such as materials processing in space. As we proceed, I am confident that our materials research staff will continue to provide important contributions which will help our nation maintain a strong technology position in these areas of growing world competition. Lewis Research Center, in partnership with U.S. industry and academia, has long been a major force in developing advanced aerospace propulsion and power systems. One key aspect that made many of these systems possible has been the availability of high-performance, reliable, and long-life materials. To assure a continuing flow of new materials and processing concepts, basic understanding to guide such innovation, and technological support for development of major NASA systems, Lewis has supported a strong in-house materials research activity. Our researchers have discovered new alloys, polymers, metallic composites, ceramics, coatings, processing techniques, etc., which are now also in use by U.S. industry. This brochure highlights selected past accomplishments of our materials research and technology staff. It also provides many examples of the facilities available with which we can conduct materials research. The nation is now beginning to consider integrating technology for high-performance supersonic/hypersonic aircraft, nuclear space power systems, a space station, and new research areas such as materials processing in space.

Stofan, Andrew J.↗

NASA NTRS2016

Aerospace Applications of Non-Equilibrium Plasma

Nonequilibrium plasma/non-thermal plasma/cold plasmas are being used in a wide range of new applications in aeronautics, active flow control, heat transfer reduction, plasma-assisted ignition and combustion, noise suppression, and power generation. Industrial applications may be found in pollution control, materials surface treatment, and water purification. In order for these plasma processes to become practical, efficient means of ionization are necessary. A primary challenge for these applications is to create a desired non-equilibrium plasma in air by preventing the discharge from transitioning into an arc. Of particular interest is the impact on simulations and experimental data with and without detailed consideration of non-equilibrium effects, and the consequences of neglecting non-equilibrium. This presentation will provide an assessment of the presence and influence of non-equilibrium phenomena for various aerospace needs and applications. Specific examples to be considered will include the forward energy deposition of laser-induced non-equilibrium plasmoids for sonic boom mitigation, weakly ionized flows obtained from pulsed nanosecond discharges for an annular Hall type MHD generator duct for turbojet energy bypass, and fundamental mechanisms affecting the design and operation of novel plasma-assisted reactive systems in dielectric liquids (water purification, in-pipe modification of fuels, etc.).

Nonequilibrium Plasma↗

NASA NTRS2008

Organic/Inorganic Polymeric Composites for Heat-Transfer Reduction

Organic/inorganic polymeric composite materials have been invented with significant reduction in heat-transfer properties. Measured decreases of 20-50 percent in thermal conductivity versus that of the unmodified polymer matrix have been attained. These novel composite materials also maintain mechanical properties of the unmodified polymer matrix. The present embodiments are applicable, but not limited to: racing applications, aerospace applications, textile industry, electronic applications, military hardware improvements, and even food service industries. One specific application of the polymeric composition is for use in tanks, pipes, valves, structural supports, and components for hot or cold fluid process systems where heat flow through materials is problematic and not desired. With respect to thermal conductivity and physical properties, these materials are superior alternatives to prior composite materials. These materials may prove useful as substitutes for metals in some cryogenic applications. A material of this type can be made from a blend of thermoplastics, elastomers, and appropriate additives and processed on normal polymer processing equipment. The resulting processed organic/inorganic composite can be made into fibers, molded, or otherwise processed into useable articles.

Smith, Trent↗

NASA NTRS1975

Materials processing in space - New challenges for industry

A summary is presented of NASA's activity in materials research in zero-g. Very simple experiments to determine the effects of zero-g upon solidification processes, upon heat flow, convection and mass transport, and upon the separation of biological cells were conducted during three Apollo flights. The investigations were continued in a series of experiments conducted on Skylab. The experiments provided data on a wide range of space-processing topics. The various tests and the results obtained in them are discussed. Attention is also given to experiments planned for the Apollo-Soyuz experiment, studies to be conducted with the aid of sounding rockets, and an evaluation of the possibilities provided by space processing for industry.

Bredt, J. H.↗

NASA NTRS1994

Space-based crystal growth and thermocapillary flow

The demand for larger crystals is increasing especially in applications associated with the electronic industry, where large and pure electronic crystals (notably silicon) are the essential material to make high-performance computer chips. Crystal growth under weightless conditions has been considered an ideal way to produce bigger and hopefully better crystals. One technique which may benefit from a microgravity environment is the float-zone crystal-growth process, a containerless method for producing high-quality electronic material. In this method, a rod of material to be refined is moved slowly through a heating device which melts a portion of it. Ideally, as the melt resolidifies it does so as a single crystal which is then used as substrate for building microelectronic devices. The possibility of contamination by contact with other material is reduced because of the 'float' configuration. However, since the weight of the material contained in the zone is supported by the surface-tension force, the size of the resulting crystal is limited in Earth-based productions; in fact, some materials have properties which prevent this process from being used to manufacture crystals of reasonable size. Consequently, there has been a great deal of interest in exploiting the microgravity environment of space to grow larger size crystals of electronic material using the float-zone method. In addition to allowing larger crystals to be grown, a microgravity environment would also significantly reduce the magnitude of convection induced by buoyancy forces during the melting state. This type of convection was once thought to be at least partially responsible for the presence of undesirable nonuniformities--called striations--in material properties observed in float-zone material. However, past experiments on crystal growth under weightless conditions found that even with the absence of gravity, the float-zone method sometimes still results striations. It is believed that another mechanism is playing a dominant role in the microgravity environment.

Shen, Yong-Hong↗