Introducing bio- and micro-technology into undergraduate thermal-fluids courses: investigating pipe pressure loss via atomic force microscopy.

PubMed

Müller, Marcus; Traum, Matthew J

2012-01-01

To introduce bio- and micro-technologies into general undergraduate thermal-fluids classes, a hands-on interdisciplinary in-class demonstration is described that juxtaposes classical pressure loss pipe flow experiments against a modern micro-characterization technique, AFM profilometry. Both approaches measure surface roughness and can segue into classroom discussions related to material selection and design of bio-medical devices to handle biological fluids such as blood. Appealing to the range of engineering students populating a general thermal-fluids course, a variety of pipe/hose/tube materials representing a spectrum of disciplines can be tested using both techniques. This in-class demonstration relies on technical content already available in standard thermal-fluids textbooks, provides experimental juxtaposition between classical and micro-technology-enabled approaches to the same experiment, and can be taught by personnel with no specialized micro- or bio-technology expertise.

21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Food and Drug Administration have revealed that heat exchange fluids for certain pasteurization equipment used in processing animal feed contain PCB's. Although heat exchange fluids in such equipment are... animal feed shall: (i) Have the heat exchange fluid used in existing equipment or machinery for handling...

21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Food and Drug Administration have revealed that heat exchange fluids for certain pasteurization equipment used in processing animal feed contain PCB's. Although heat exchange fluids in such equipment are... animal feed shall: (i) Have the heat exchange fluid used in existing equipment or machinery for handling...

The Voronoi Implicit Interface Method for computing multiphase physics

PubMed Central

Saye, Robert I.; Sethian, James A.

2011-01-01

We introduce a numerical framework, the Voronoi Implicit Interface Method for tracking multiple interacting and evolving regions (phases) whose motion is determined by complex physics (fluids, mechanics, elasticity, etc.), intricate jump conditions, internal constraints, and boundary conditions. The method works in two and three dimensions, handles tens of thousands of interfaces and separate phases, and easily and automatically handles multiple junctions, triple points, and quadruple points in two dimensions, as well as triple lines, etc., in higher dimensions. Topological changes occur naturally, with no surgery required. The method is first-order accurate at junction points/lines, and of arbitrarily high-order accuracy away from such degeneracies. The method uses a single function to describe all phases simultaneously, represented on a fixed Eulerian mesh. We test the method’s accuracy through convergence tests, and demonstrate its applications to geometric flows, accurate prediction of von Neumann’s law for multiphase curvature flow, and robustness under complex fluid flow with surface tension and large shearing forces. PMID:22106269

The Voronoi Implicit Interface Method for computing multiphase physics.

PubMed

Saye, Robert I; Sethian, James A

2011-12-06

We introduce a numerical framework, the Voronoi Implicit Interface Method for tracking multiple interacting and evolving regions (phases) whose motion is determined by complex physics (fluids, mechanics, elasticity, etc.), intricate jump conditions, internal constraints, and boundary conditions. The method works in two and three dimensions, handles tens of thousands of interfaces and separate phases, and easily and automatically handles multiple junctions, triple points, and quadruple points in two dimensions, as well as triple lines, etc., in higher dimensions. Topological changes occur naturally, with no surgery required. The method is first-order accurate at junction points/lines, and of arbitrarily high-order accuracy away from such degeneracies. The method uses a single function to describe all phases simultaneously, represented on a fixed Eulerian mesh. We test the method's accuracy through convergence tests, and demonstrate its applications to geometric flows, accurate prediction of von Neumann's law for multiphase curvature flow, and robustness under complex fluid flow with surface tension and large shearing forces.

The Voronoi Implicit Interface Method for computing multiphase physics

DOE PAGES

Saye, Robert I.; Sethian, James A.

2011-11-21

In this paper, we introduce a numerical framework, the Voronoi Implicit Interface Method for tracking multiple interacting and evolving regions (phases) whose motion is determined by complex physics (fluids, mechanics, elasticity, etc.), intricate jump conditions, internal constraints, and boundary conditions. The method works in two and three dimensions, handles tens of thousands of interfaces and separate phases, and easily and automatically handles multiple junctions, triple points, and quadruple points in two dimensions, as well as triple lines, etc., in higher dimensions. Topological changes occur naturally, with no surgery required. The method is first-order accurate at junction points/lines, and of arbitrarilymore » high-order accuracy away from such degeneracies. The method uses a single function to describe all phases simultaneously, represented on a fixed Eulerian mesh. Finally, we test the method’s accuracy through convergence tests, and demonstrate its applications to geometric flows, accurate prediction of von Neumann’s law for multiphase curvature flow, and robustness under complex fluid flow with surface tension and large shearing forces.« less

A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems

NASA Technical Reports Server (NTRS)

Mason, Lee S.; Siamidis, John

2006-01-01

This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H20 for the HRS pumped loop coolant working fluid. A detailed Microsoft Excel (Microsoft Corporation, Redmond, WA) analytical model, HRS_Opt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids.

A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems

NASA Technical Reports Server (NTRS)

Siamidis, John; Mason, Lee S.

2006-01-01

This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H2O for the HRS pumped loop coolant working fluid. A detailed Microsoft Excel (Microsoft Corporation, Redmond, WA) analytical model, HRS_Opt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids.

A Comparison of Coolant Options for Brayton Power Conversion Heat Rejection Systems

NASA Astrophysics Data System (ADS)

Siamidis, John; Mason, Lee

2006-01-01

This paper describes potential heat rejection design concepts for Brayton power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) and surface power applications. The Brayton Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Sodium potassium (NaK) and H2O are two coolant working fluids that have been investigated in the design of a pumped loop and heat pipe space HRS. In general NaK systems are high temperature (300 to 1000 K) low pressure systems, and H2O systems are low temperature (300 to 600 K) high pressure systems. NaK is an alkali metal with health and safety hazards that require special handling procedures. On the other hand, H2O is a common fluid, with no health hazards and no special handling procedures. This paper compares NaK and H2O for the HRS pumped loop coolant working fluid. A detailed excel analytical model, HRS_Opt, was developed to evaluate the various HRS design parameters. It is capable of analyzing NaK or H2O coolant, parallel or series flow configurations, and numerous combinations of other key parameters (heat pipe spacing, diameter and radial flux, radiator facesheet thickness, fluid duct system pressure drop, system rejected power, etc.) of the HRS. This paper compares NaK against water for the HRS coolant working fluid with respect to the relative mass, performance, design and implementation issues between the two fluids.

Coaxial twin-shaft magnetic fluid seals applied in vacuum wafer-handling robot

NASA Astrophysics Data System (ADS)

Cong, Ming; Wen, Haiying; Du, Yu; Dai, Penglei

2012-07-01

Compared with traditional mechanical seals, magnetic fluid seals have unique characters of high airtightness, minimal friction torque requirements, pollution-free and long life-span, widely used in vacuum robots. With the rapid development of Integrate Circuit (IC), there is a stringent requirement for sealing wafer-handling robots when working in a vacuum environment. The parameters of magnetic fluid seals structure is very important in the vacuum robot design. This paper gives a magnetic fluid seal device for the robot. Firstly, the seal differential pressure formulas of magnetic fluid seal are deduced according to the theory of ferrohydrodynamics, which indicate that the magnetic field gradient in the sealing gap determines the seal capacity of magnetic fluid seal. Secondly, the magnetic analysis model of twin-shaft magnetic fluid seals structure is established. By analyzing the magnetic field distribution of dual magnetic fluid seal, the optimal value ranges of important parameters, including parameters of the permanent magnetic ring, the magnetic pole tooth, the outer shaft, the outer shaft sleeve and the axial relative position of two permanent magnetic rings, which affect the seal differential pressure, are obtained. A wafer-handling robot equipped with coaxial twin-shaft magnetic fluid rotary seals and bellows seal is devised and an optimized twin-shaft magnetic fluid seals experimental platform is built. Test result shows that when the speed of the two rotational shafts ranges from 0-500 r/min, the maximum burst pressure is about 0.24 MPa. Magnetic fluid rotary seals can provide satisfactory performance in the application of wafer-handling robot. The proposed coaxial twin-shaft magnetic fluid rotary seal provides the instruction to design high-speed vacuum robot.

Prey handling using whole-body fluid dynamics in batoids.

PubMed

Wilga, Cheryl D; Maia, Anabela; Nauwelaerts, Sandra; Lauder, George V

2012-02-01

Fluid flow generated by body movements is a foraging tactic that has been exploited by many benthic species. In this study, the kinematics and hydrodynamics of prey handling behavior in little skates, Leucoraja erinacea, and round stingrays, Urobatis halleri, are compared using kinematics and particle image velocimetry. Both species use the body to form a tent to constrain the prey with the pectoral fin edges pressed against the substrate. Stingrays then elevate the head, which increases the volume between the body and the substrate to generate suction, while maintaining pectoral fin contact with the substrate. Meanwhile, the tip of the rostrum is curled upwards to create an opening where fluid is drawn under the body, functionally analogous to suction-feeding fishes. Skates also rotate the rostrum upwards although with the open rostral sides and the smaller fin area weaker fluid flow is generated. However, skates also use a rostral strike behavior in which the rostrum is rapidly rotated downwards pushing fluid towards the substrate to potentially stun or uncover prey. Thus, both species use the anterior portion of the body to direct fluid flow to handle prey albeit in different ways, which may be explained by differences in morphology. Rostral stiffness and pectoral fin insertion onto the rostrum differ between skates and rays and this corresponds to behavioral differences in prey handling resulting in distinct fluid flow patterns. The flexible muscular rostrum and greater fin area of stingrays allow more extensive use of suction to handle prey while the stiff cartilaginous rostrum of skates lacking extensive fin insertion is used as a paddle to strike prey as well as to clear away sand cover. Copyright © 2011 Elsevier GmbH. All rights reserved.

From viscous to elastic sheets: Dynamics of smectic freely floating films

NASA Astrophysics Data System (ADS)

Harth, Kirsten; May, Kathrin; Trittel, Torsten; Stannarius, Ralf

2015-03-01

Oscillations and rupture of bubbles, composed of an inner fluid separated from an outer fluid by a membrane, represent an old but still immensely active field of research. Membrane properties except surface tension are often neglected for simple fluid films (e.g. soap bubbles), whereas they govern the dynamics in systems with more complex membranes (e.g. vesicles). Due to their layered phase structure, smectic liquid crystals can form stable, uniform and easy-to handle fluid films of immense aspect ratios. Recently, freely floating bubbles detached from a support were prepared. We analyze the relaxation from strongly non-spherical shapes and the rupture dynamics of such bubbles using high-speed video recordings. Peculiar dynamics intermediate between those of simple viscous fluid films and an elastic response emerge: Oscillations, slowed relaxation and even the formation of wrinkles and extrusions. We characterize these phenomena and propose explanations. We acknowledge funding by the German Aerospace Center DLR within Project OASIS-CO and German Science Foundation Project STA 425-28.

Theoretical Insights for Practical Handling of Pressurized Fluids

ERIC Educational Resources Information Center

Aranda, Alfonso; Rodriguez, Maria del Prado

2006-01-01

The practical scenarios discussed in a chemistry or chemical engineering course that use solid or liquid reactants are presented. Important ideas to be considered when handling pressurized fluids are provided and three typical examples are described to enable students develop secondary skills such as the selective search of data, identification of…

Combined effects of magnetic field and partial slip on obliquely striking rheological fluid over a stretching surface

NASA Astrophysics Data System (ADS)

Nadeem, S.; Mehmood, Rashid; Akbar, Noreen Sher

2015-03-01

This study explores the collective effects of partial slip and transverse magnetic field on an oblique stagnation point flow of a rheological fluid. The prevailing momentum equations are designed by manipulating Casson fluid model. By applying the suitable similarity transformations, the governing system of equations is being transformed into coupled nonlinear ordinary differential equations. The resulting system is handled numerically through midpoint integration scheme together with Richardson's extrapolation. It is found that both normal and tangential velocity profiles decreases with an increase in magnetic field as well as slip parameter. Streamlines pattern are presented to study the actual impact of slip mechanism and magnetic field on the oblique flow. A suitable comparison with the previous literature is also provided to confirm the accuracy of present results for the limiting case.

Open-atmosphere sustenance of highly volatile attoliter-size droplets on surfaces.

PubMed

Galliker, Patrick; Schneider, Julian; Rüthemann, Lukas; Poulikakos, Dimos

2013-08-13

The controlled formation and handling of minute liquid volumes on surfaces is essential to the success of microfluidics in biology, chemistry, and materials applications. Even though current methods have demonstrated their potential in a variety of experimental assays, there remain significant difficulties concerning breadth of applicability, standardization, throughput, and economics. Here we introduce a unique microfluidic paradigm in which microscopic volatile droplets are formed, sustained, and manipulated in size and content at any desired spot on unpatterned substrates. Their sustainability is warranted by continuous replacement of the rapidly vaporizing sessile fluid through controlled equivalent volume deposition of smaller discrete liquid entities by an electrohydrodynamic nanodripping process. Using nanoparticle inks we show that the concentration of solutes in so-stabilized droplets can be linearly increased at isochoric conditions and user-defined rates. An intriguing insensitivity of the droplet shape toward surface heterogeneities ensures robustness and experimental reproducibility, even when handling attoliter quantities. The unique capabilities and technical simplicity of the presented method introduce a high degree of flexibility and make it pertinent to a diverse range of applications.

Open-atmosphere sustenance of highly volatile attoliter-size droplets on surfaces

PubMed Central

Galliker, Patrick; Schneider, Julian; Rüthemann, Lukas; Poulikakos, Dimos

2013-01-01

The controlled formation and handling of minute liquid volumes on surfaces is essential to the success of microfluidics in biology, chemistry, and materials applications. Even though current methods have demonstrated their potential in a variety of experimental assays, there remain significant difficulties concerning breadth of applicability, standardization, throughput, and economics. Here we introduce a unique microfluidic paradigm in which microscopic volatile droplets are formed, sustained, and manipulated in size and content at any desired spot on unpatterned substrates. Their sustainability is warranted by continuous replacement of the rapidly vaporizing sessile fluid through controlled equivalent volume deposition of smaller discrete liquid entities by an electrohydrodynamic nanodripping process. Using nanoparticle inks we show that the concentration of solutes in so-stabilized droplets can be linearly increased at isochoric conditions and user-defined rates. An intriguing insensitivity of the droplet shape toward surface heterogeneities ensures robustness and experimental reproducibility, even when handling attoliter quantities. The unique capabilities and technical simplicity of the presented method introduce a high degree of flexibility and make it pertinent to a diverse range of applications. PMID:23898173

Flow and Sedimentation of particulate suspensions in Fractures

NASA Astrophysics Data System (ADS)

Lo, Tak Shing; Koplik, Joel

2011-03-01

Suspended particles are commonly found in reservoir fluids. They alter the rheology of the flowing liquids and may obstruct transport by narrowing flow channels due to gravitational sedimentation. An understanding of the dynamics of particle transport and deposition is, therefore, important to many geological, enviromental and industrial processes. Realistic geological fractures usually have irregular surfaces with self-affine structures, and the surface roughness plays a crucial role in the flow and sedimentation processes. Recently, we have used the lattice Boltzmann method to study the combined effects of sedimentation and transport of particles suspended in a Newtonian fluid in a pressure-driven flow in self-affine channels, which is especially relevant to clogging phenomena where sediments may block fluid flows in narrow constrictions of the channels. The lattice Boltzmann method is flexible and particularly suitable for handling irregular geometry. Our work covers a broad range in Reynolds and buoyancy numbers, and in particle concentrations. In this talk, we focus on the transitions between the ``jammed'' and the ``flow'' states in fractures, and on the effects of nonuniform particle size distributions. Work supported by DOE and NERSC.

Bubble formation in microgravity

NASA Technical Reports Server (NTRS)

Antar, Basil N.

1994-01-01

Two KC-135 flight campaigns have been conducted to date which are specifically dedicated to study bubble formation in microgravity. The first flight was conducted during March 14-18, 1994, and the other during June 20-24, 1994. The results from the June 1994 flight have not been analyzed yet, while the results from the March flight have been partially analyzed. In the first flight three different experiments were performed, one with the specific aim at determining whether or not cavitation can take place during any of the fluid handling procedures adopted in the shuttle bioprocessing experiments. The other experiments were concerned with duplicating some of the procedures that resulted in bubble formation, namely the NCS filling procedure and the needle scratch of a solid surface. The results from this set of experiments suggest that cavitation did not take place during any of the fluid handling procedures. The results clearly indicate that almost all were generated as a result of the breakup of the gas/liquid interface. This was convincingly demonstrated in the scratch tests as well as in the liquid fill tests.

From viscous to elastic sheets: Dynamics of smectic bubbles

NASA Astrophysics Data System (ADS)

Harth, Kirsten; Trittel, Torsten; van der Meer, Devaraj; Stannarius, Ralf

2015-11-01

Oscillations and rupture of bubbles composed of an inner fluid separated from an outer fluid by a membrane, represent an old but still immensely active field of research. Membrane properties apart from surface tension are often neglected for fluids (e.g. soap bubbles), whereas they govern the dynamics in systems with a rigid membrane (e.g. vesicles). Due to their layered phase structure, smectic liquid crystals can form stable, uniform and easy-to-handle fluid films of immense aspect ratios. Only recently, freely floating bubbles detached from a support could be prepared. We analyze their relaxation from strongly non-spherical shapes and the rupture using high-speed video recordings. Peculiar dynamics intermediate between simple viscous fluid films and an elastic response are observed: Fast oscillations, slowed relaxation and even the reversible formation of wrinkles and extrusions. Bubble rupture deviates qualitatively from previously observed behavior of simple Newtonian and other complex fluids. It becomes retarded by at least two orders of magnitude compared to the predictions of Taylor and Culick. A transition between fluid-like and elastic behavior is seen with increasing thickness. We give experimental results, an intuitive explanation and a novel hydrodynamic description.

Montmorillonite Dissolution in Simulated Lung Fluids

NASA Astrophysics Data System (ADS)

Schmidt, M.; Wendlandt, R. F.

2008-12-01

Because lung fluids" first interaction is with the surface of inhaled grains, the surface properties of inhaled mineral dusts may have a generally mitigating effect on cytotoxicity and carcinogenicity. Wendlandt et al. (Appl. Geochem. 22, 2007) investigated the surface properties of respirable-sized quartz grains in bentonites and recognized pervasive montmorillonite surface coatings on silica grains. The purpose of this study was to determine the dissolution rate and biodurability of montmorillonite in simulated lung fluids and to assess its potential to mitigate silica cytotoxicity. Modified batch reaction experiments were conducted on purified and size fractionated calcic (SAz-2; 0.4-5 μm) and sodic (DC-2; 0.4-2 μm) montmorillonites for 120 to 160 days of reaction time at 37°C in both simulated extracellular lung fluid (Lu) and simulated lysosomal fluid (Ly). Modified batch experiments simulated a flow-through setup and minimized sample handling difficulties. Reacted Lu and Ly fluid was analyzed for Mg, Al, and Si on an ICP-OE spectrometer. Steady state dissolution was reached 90-100 days after the start of the experiment and maintained for 40-60 days. Measured montmorillonite dissolution rates based on BET surface areas and Si steady state release range from 4.1x10-15 mol/m2/s at the slowest to 1.0x10-14 mol/m2/s at the fastest with relative uncertainties of less than 10%. Samples reacting in Ly (pH = 4.55) dissolved faster than those in Lu (pH = 7.40), and DC-2 dissolved faster than SAz-2. The measured range of biodurabilities was 1,300 to 3,400 years for a 1 μm grain assuming a spherical volume and a molar volume equal to that of illite. The difference in salinities of the two fluids was too slight to draw conclusions about the relationship of ionic strength to dissolution rate. Results indicate that montmorillonite dissolution is incongruent and edge controlled. Dissolution rates for DC- 2 and SAz-2 clays were comparable to those reported in the literature. Biodurability results fall well beyond the lifespan of humans confirming montmorillonite's potential to mitigate silica cytotoxicity.

Syndrome of transient headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) in a patient with confusional symptoms, diffuse EEG abnormalities, and bilateral vasospasm in transcranial Doppler ultrasound: A case report and literature review.

PubMed

Hidalgo de la Cruz, M; Domínguez Rubio, R; Luque Buzo, E; Díaz Otero, F; Vázquez Alén, P; Orcajo Rincón, J; Prieto Montalvo, J; Contreras Chicote, A; Grandas Pérez, F

2017-04-17

HaNDL syndrome (transient headache and neurological deficits with cerebrospinal fluid lymphocytosis) is characterised by one or more episodes of headache and transient neurological deficits associated with cerebrospinal fluid lymphocytosis. To date, few cases of HaNDL manifesting with confusional symptoms have been described. Likewise, very few patients with HaNDL and confusional symptoms have been evaluated with transcranial Doppler ultrasound (TCD). TCD data from patients with focal involvement reveal changes consistent with vasomotor alterations. We present the case of a 42-year-old man who experienced headache and confusional symptoms and displayed pleocytosis, diffuse slow activity on EEG, increased blood flow velocity in both middle cerebral arteries on TCD, and single-photon emission computed tomography (SPECT) findings suggestive of diffuse involvement, especially in the left hemisphere. To our knowledge, this is the first description of a patient with HaNDL, confusional symptoms, diffuse slow activity on EEG, and increased blood flow velocity in TCD. Our findings suggest a relationship between cerebral vasomotor changes and the pathophysiology of HaNDL. TCD may be a useful tool for early diagnosis of HaNDL. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Flow in porous media, phase and ultralow interfacial tensions: Mechanisms of enhanced petroleum recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, H.T.; Scriven, L.E.

1991-07-01

A major program of university research, longer-ranged and more fundamental in approach than industrial research, into basic mechanisms of enhancing petroleum recovery and into underlying physics, chemistry, geology, applied mathematics, computation, and engineering science has been built at Minnesota. The original focus was surfactant-based chemical flooding, but the approach taken was sufficiently fundamental that the research, longer-ranged than industrial efforts, has become quite multidirectional. Topics discussed are volume controlled porosimetry; fluid distribution and transport in porous media at low wetting phase saturation; molecular dynamics of fluids in ultranarrow pores; molecular dynamics and molecular theory of wetting and adsorption; new numericalmore » methods to handle initial and boundary conditions in immiscible displacement; electron microscopy of surfactant fluid microstructure; low cost system for animating liquid crystallites viewed with polarized light; surfaces of constant mean curvature with prescribed contact angle.« less

Towards an integrated optofluidic system for highly sensitive detection of antibiotics in seawater incorporating bimodal waveguide photonic biosensors and complex, active microfluidics

NASA Astrophysics Data System (ADS)

Szydzik, C.; Gavela, A. F.; Roccisano, J.; Herranz de Andrés, S.; Mitchell, A.; Lechuga, L. M.

2016-12-01

We present recent results on the realisation and demonstration of an integrated optofluidic lab-on-a-chip measurement system. The system consists of an integrated on-chip automated microfluidic fluid handling subsystem, coupled with bimodal nano-interferometer waveguide technology, and is applied in the context of detection of antibiotics in seawater. The bimodal waveguide (BMWG) is a highly sensitive label-free biosensor. Integration of complex microfluidic systems with bimodal waveguide technology enables on-chip sample handling and fluid processing capabilities and allows for significant automation of experimental processes. The on-chip fluid-handling subsystem is realised through the integration of pneumatically actuated elastomer pumps and valves, enabling high temporal resolution sample and reagent delivery and facilitating multiplexed detection processes.

Geothermal Produced Fluids: Characteristics, Treatment Technologies, and Management Options

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finster, Molly; Clark, Corrie; Schroeder, Jenna

2015-10-01

Geothermal power plants use geothermal fluids as a resource and create waste residuals as part of the power generation process. Both the geofluid resource and the waste stream are considered produced fluids. The chemical and physical nature of produced fluids can have a major impact on the geothermal power industry and can influence the feasibility of geothermal power development, exploration approaches, power plant design, operating practices, and the reuse or disposal of residuals. In general, produced fluids include anything that comes out of a geothermal field and that subsequently must be managed on the surface. These fluids vary greatly dependingmore » on the geothermal reservoir being harnessed, power plant design, and the life cycle stage in which the fluid exists, but generally include water and fluids used to drill geothermal wells, fluids used to stimulate wells in enhanced geothermal systems, and makeup and/or cooling water used during operation of a geothermal power plant. Additional geothermal-related produced fluids include many substances that are similar to waste streams from the oil and gas industry, such as scale, flash tank solids, precipitated solids from brine treatment, hydrogen sulfide, and cooling-tower-related waste. This review paper aims to provide baseline knowledge on specific technologies and technology areas associated with geothermal power production. Specifically, this research focused on the management techniques related to fluids produced and used during the operational stage of a geothermal power plant; the vast majority of which are employed in the generation of electricity. The general characteristics of produced fluids are discussed. Constituents of interest that tend to drive the selection of treatment technologies are described, including total dissolved solids, noncondensable gases, scale and corrosion, silicon dioxide, metal sulfides, calcium carbonate, corrosion, metals, and naturally occurring radioactive material. Management options for produced fluids that require additional treatment for these constituents are also discussed, including surface disposal, reuse and recycle, agricultural industrial and domestic uses, mineral extraction and recovery, and solid waste handling.« less

Palliative care - fluid, food, and digestion

MedlinePlus

... gov/ency/patientinstructions/000531.htm Palliative care - fluid, food, and digestion To use the sharing features on ... When Your Body Has Problems Handling Fluids and Food It is normal for a person who has ...

Resource Manual for Handling Body Fluids in the School Setting To Prevent Transmission of Human Immunodeficiency Virus and Hepatitis B Virus. Revised Edition.

ERIC Educational Resources Information Center

Maryland State Dept. of Health and Mental Hygiene, Baltimore.

This Maryland resource manual provides local education agencies with guidelines on how to handle body fluids to prevent the transmission of diseases, especially Human Immunodeficiency Virus (HIV) and Hepatitis B Virus (HBV), in the school setting. The first section summarizes the reasons for development of the manual. The second section summarizes…

Contaminated product water as the source of Phialemonium curvatum bloodstream infection among patients undergoing hemodialysis.

PubMed

Rao, Carol Y; Pachucki, Constance; Cali, Salvatore; Santhiraj, Mangai; Krankoski, Kathi L K; Noble-Wang, Judith A; Leehey, David; Popli, Subhash; Brandt, Mary E; Lindsley, Mark D; Fridkin, Scott K; Arduino, Matthew J

2009-09-01

We investigated a cluster of cases of bloodstream infection (BSI) due to the mold Phialemonium at a hemodialysis center in Illinois and conducted a cohort study to identify risk factors. Environmental assessment and cohort study. A hemodialysis center in a tertiary care hospital. A case patient was defined as a person who underwent dialysis at the center and had a blood sample that tested positive for Phialemonium curvatum on culture. We reviewed microbiology and medical records and tested water, surface, and dialysate samples by culture. Molds isolated from environmental and clinical specimens were identified by their morphological features and confirmed by sequencing DNA. We identified 2 case patients with BSI due to P. curvatum. Both became febrile and hypotensive while undergoing dialysis on the same machine at the same treatment station, although on different days. Dialysis machines were equipped with waste handling option ports that are used to discard dialyzer priming fluid. We isolated P. curvatum from the product water (ie, water used for dialysis purposes) at 2 of 19 treatment stations, one of which was the implicated station. The source of P. curvatum was likely the water distribution system. To our knowledge, this is the first report of patients acquiring a mold BSI from contaminated product water. The route of exposure in these cases of BSI due to P. curvatum may be related to the malfunction and improper maintenance of the waste handling option ports. Waste handling option ports have been previously implicated as the source of bacterial BSI due to the backflow of waste fluid into a patient's blood line. No additional cases of infection were noted after remediation of the water distribution system and after discontinuing use of waste handling option ports at the facility.

A comparison of the in vitro moisture vapour transmission rate and in vivo fluid-handling capacity of six adhesive foam dressings to a newly reformulated adhesive foam dressing.

PubMed

Zehrer, Cindy L; Holm, David; Solfest, Staci E; Walters, Shelley-Ann

2014-12-01

This study compared moisture vapour transmission rate (MVTR) and wear time or fluid-handling capacities of six adhesive foam dressings to a reformulated control dressing. Standardised in vitro MVTR methodology and a previously published in vivo artificial wound model (AWM) were used. Mean inverted MVTR for the reformulated dressing was 12 750 g/m(2) /24 hours and was significantly higher than four of the six comparator dressings (P < 0·0001), which ranged from 830 to 11 360 g/m(2) /24 hours. Mean upright MVTR for the reformulated dressing was 980 g/m(2) /24 hours and was significantly different than all of the comparator dressings (P < 0·0001), which ranged from 80 to 1620 g/m(2) /24 hours (three higher/three lower). The reformulated dressing median wear time ranged from 6·1 to >7·0 days, compared with 1·0 to 3·5 days for the comparator dressings (P = 0·0012 to P < 0·0001). The median fluid volume handled ranged from 78·0 to >87 ml compared with 13·0 to 44·5 ml for the comparator dressings (P = 0·0007 to P < 0·001). Interestingly, inverted MVTR did not correspond well to the AWM. These results suggest that marked differences exist between the dressings in terms of both MVTR and wear time or fluid-handling capacity. Furthermore, high inverted MVTR does not necessarily predict longer wear time or fluid-handling capacities of absorbent dressings. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Automatic sequential fluid handling with multilayer microfluidic sample isolated pumping

PubMed Central

Liu, Jixiao; Fu, Hai; Yang, Tianhang; Li, Songjing

2015-01-01

To sequentially handle fluids is of great significance in quantitative biology, analytical chemistry, and bioassays. However, the technological options are limited when building such microfluidic sequential processing systems, and one of the encountered challenges is the need for reliable, efficient, and mass-production available microfluidic pumping methods. Herein, we present a bubble-free and pumping-control unified liquid handling method that is compatible with large-scale manufacture, termed multilayer microfluidic sample isolated pumping (mμSIP). The core part of the mμSIP is the selective permeable membrane that isolates the fluidic layer from the pneumatic layer. The air diffusion from the fluidic channel network into the degassing pneumatic channel network leads to fluidic channel pressure variation, which further results in consistent bubble-free liquid pumping into the channels and the dead-end chambers. We characterize the mμSIP by comparing the fluidic actuation processes with different parameters and a flow rate range of 0.013 μl/s to 0.097 μl/s is observed in the experiments. As the proof of concept, we demonstrate an automatic sequential fluid handling system aiming at digital assays and immunoassays, which further proves the unified pumping-control and suggests that the mμSIP is suitable for functional microfluidic assays with minimal operations. We believe that the mμSIP technology and demonstrated automatic sequential fluid handling system would enrich the microfluidic toolbox and benefit further inventions. PMID:26487904

Biotechnology for Solar System Exploration

NASA Astrophysics Data System (ADS)

Steele, A.; Maule, J.; Toporski, J.; Parro-Garcia, V.; Briones, C.; Schweitzer, M.; McKay, D.

With the advent of a new era of astrobiology missions in the exploration of the solar system and the search for evidence of life elsewhere, we present a new approach to this goal, the integration of biotechnology. We have reviewed the current list of biotechnology techniques, which are applicable to miniaturization, automatization and integration into a combined flight platform. Amongst the techniques reviewed are- The uses of antibodies- Fluorescent detection strategies- Protein and DNA chip technology- Surface plasmon resonance and its relation to other techniques- Micro electronic machining (MEMS where applicable to biologicalsystems)- nanotechnology (e.g. molecular motors)- Lab-on-a-chip technology (including PCR)- Mass spectrometry (i.e. MALDI-TOF)- Fluid handling and extraction technologies- Chemical Force Microscopy (CFM)- Raman Spectroscopy We have begun to integrate this knowledge into a single flight instrument approach for the sole purpose of combining several mutually confirming tests for life, organic and/or microbial contamination, as well as prebiotic and abiotic organic chemicals. We will present several innovative designs for new instrumentation including pro- engineering design drawings of a protein chip reader for space flight and fluid handling strategies. We will also review the use of suitable extraction methodologies for use on different solar system bodies.

Development of a bionanodevice for detecting stress levels

NASA Astrophysics Data System (ADS)

Nomura, S.; Handri, S.; Honda, H.

2011-03-01

Recent advances in molecular analysis techniques have enabled scientists to assess the tiny amounts of biochemical substances secreted in our bodies. This has revealed that the levels of various secretory hormones and immune substances vary sensitively with the mental state of a person. Such hormones and immune substances exhibit transient increases with various psychological stressors. They thus have the potential to be used as a novel biometric for monitoring stress. Biomarkers that occur in saliva can be monitored non-invasively and are thus potentially useful as practical indicators of mental stress. Stress biomarkers are considered to be released into the blood stream or other secretory fluids by physiological stress reactions. Stress biomarkers are expected to be detectable in sweat and other humoral fluids that are exuded from the skin surface. Based on this, we have developed a bionanodevice for detecting stress by capturing stress biomarkers on the skin surface in a non-invasive manner. A prototype bionanodevice is described in which a motor protein is introduced for molecular handling.

Cryogenic Fluid Management Technology for Moon and Mars Missions

NASA Technical Reports Server (NTRS)

Doherty, Michael P.; Gaby, Joseph D.; Salerno, Louis J.; Sutherlin, Steven G.

2010-01-01

In support of the U.S. Space Exploration Policy, focused cryogenic fluid management technology efforts are underway within the National Aeronautics and Space Administration. Under the auspices of the Exploration Technology Development Program, cryogenic fluid management technology efforts are being conducted by the Cryogenic Fluid Management Project. Cryogenic Fluid Management Project objectives are to develop storage, transfer, and handling technologies for cryogens to support high performance demands of lunar, and ultimately, Mars missions in the application areas of propulsion, surface systems, and Earth-based ground operations. The targeted use of cryogens and cryogenic technologies for these application areas is anticipated to significantly reduce propellant launch mass and required on-orbit margins, to reduce and even eliminate storage tank boil-off losses for long term missions, to economize ground pad storage and transfer operations, and to expand operational and architectural operations at destination. This paper organizes Cryogenic Fluid Management Project technology efforts according to Exploration Architecture target areas, and discusses the scope of trade studies, analytical modeling, and test efforts presently underway, as well as future plans, to address those target areas. The target areas are: liquid methane/liquid oxygen for propelling the Altair Lander Ascent Stage, liquid hydrogen/liquid oxygen for propelling the Altair Lander Descent Stage and Ares V Earth Departure Stage, liquefaction, zero boil-off, and propellant scavenging for Lunar Surface Systems, cold helium and zero boil-off technologies for Earth-Based Ground Operations, and architecture definition studies for long term storage and on-orbit transfer and pressurization of LH2, cryogenic Mars landing and ascent vehicles, and cryogenic production via in situ resource utilization on Mars.

Supercritical Fuel Measurements

DTIC Science & Technology

2012-09-01

TERMS Fuels, supercritical fluids , stimulated scattering, Brillouin scattering, Rayleigh scattering, elastic properties, thermal properties 16...10 Supercritical Cell and Fluid Handling ....................................................................................... 11...motion in supercritical fluids . Thus, the method can perform diagnostics on the heat transfer of high-temperature and high-pressure fuels, measuring

Simulation of Two-Fluid Flows by the Least-Squares Finite Element Method Using a Continuum Surface Tension Model

NASA Technical Reports Server (NTRS)

Wu, Jie; Yu, Sheng-Tao; Jiang, Bo-nan

1996-01-01

In this paper a numerical procedure for simulating two-fluid flows is presented. This procedure is based on the Volume of Fluid (VOF) method proposed by Hirt and Nichols and the continuum surface force (CSF) model developed by Brackbill, et al. In the VOF method fluids of different properties are identified through the use of a continuous field variable (color function). The color function assigns a unique constant (color) to each fluid. The interfaces between different fluids are distinct due to sharp gradients of the color function. The evolution of the interfaces is captured by solving the convective equation of the color function. The CSF model is used as a means to treat surface tension effect at the interfaces. Here a modified version of the CSF model, proposed by Jacqmin, is used to calculate the tension force. In the modified version, the force term is obtained by calculating the divergence of a stress tensor defined by the gradient of the color function. In its analytical form, this stress formulation is equivalent to the original CSF model. Numerically, however, the use of the stress formulation has some advantages over the original CSF model, as it bypasses the difficulty in approximating the curvatures of the interfaces. The least-squares finite element method (LSFEM) is used to discretize the governing equation systems. The LSFEM has proven to be effective in solving incompressible Navier-Stokes equations and pure convection equations, making it an ideal candidate for the present applications. The LSFEM handles all the equations in a unified manner without any additional special treatment such as upwinding or artificial dissipation. Various bench mark tests have been carried out for both two dimensional planar and axisymmetric flows, including a dam breaking, oscillating and stationary bubbles and a conical liquid sheet in a pressure swirl atomizer.

Analysis of solid particles falling down and interacting in a channel with sedimentation using fictitious boundary method

NASA Astrophysics Data System (ADS)

Usman, K.; Walayat, K.; Mahmood, R.; Kousar, N.

2018-06-01

We have examined the behavior of solid particles in particulate flows. The interaction of particles with each other and with the fluid is analyzed. Solid particles can move freely through a fixed computational mesh using an Eulerian approach. Fictitious boundary method (FBM) is used for treating the interaction between particles and the fluid. Hydrodynamic forces acting on the particle's surface are calculated using an explicit volume integral approach. A collision model proposed by Glowinski, Singh, Joseph and coauthors is used to handle particle-wall and particle-particle interactions. The particulate flow is computed using multigrid finite element solver FEATFLOW. Numerical experiments are performed considering two particles falling and colliding and sedimentation of many particles while interacting with each other. Results for these experiments are presented and compared with the reference values. Effects of the particle-particle interaction on the motion of the particles and on the physical behavior of the fluid-particle system has been analyzed.

Design Constraints Regarding The Use Of Fluids In Emergency Medical Systems For Space Flight

NASA Technical Reports Server (NTRS)

McQuillen, John

2013-01-01

The Exploration Medical Capability Project of the Human Research Program is tasked with identifying, investigating and addressing gaps existing gaps in either knowledge or technology that need to be addressed in order to enable safer exploration missions. There are several gaps that involve treatment for emergency medical situations. Some of these treatments involve the handling of liquids in the spacecraft environment which involve gas-liquid mixtures handling, dissolution chemistry and thermal issues. Some of the recent technology efforts include the Intravenous fluid generation (IVGEN) experiment, the In-Suit Injection System (ISIS) experiment, and medical suction. Constraints include limited volume, shelf life, handling biohazards, availability of power, crew time and medical training.

A level set method for determining critical curvatures for drainage and imbibition.

PubMed

Prodanović, Masa; Bryant, Steven L

2006-12-15

An accurate description of the mechanics of pore level displacement of immiscible fluids could significantly improve the predictions from pore network models of capillary pressure-saturation curves, interfacial areas and relative permeability in real porous media. If we assume quasi-static displacement, at constant pressure and surface tension, pore scale interfaces are modeled as constant mean curvature surfaces, which are not easy to calculate. Moreover, the extremely irregular geometry of natural porous media makes it difficult to evaluate surface curvature values and corresponding geometric configurations of two fluids. Finally, accounting for the topological changes of the interface, such as splitting or merging, is nontrivial. We apply the level set method for tracking and propagating interfaces in order to robustly handle topological changes and to obtain geometrically correct interfaces. We describe a simple but robust model for determining critical curvatures for throat drainage and pore imbibition. The model is set up for quasi-static displacements but it nevertheless captures both reversible and irreversible behavior (Haines jump, pore body imbibition). The pore scale grain boundary conditions are extracted from model porous media and from imaged geometries in real rocks. The method gives quantitative agreement with measurements and with other theories and computational approaches.

Toroidal cell and battery. [storage battery for high amp-hour load applications

NASA Technical Reports Server (NTRS)

Nagle, W. J. (Inventor)

1981-01-01

A toroidal storage battery designed to handle relatively high amp-hour loads is described. The cell includes a wound core disposed within a pair of toroidal channel shaped electrodes spaced apart by nylon insulator. The shape of the case electrodes of this toroidal cell allows a first planar doughnut shaped surface and the inner cylindrical case wall to be used as a first electrode and a second planar doughnut shaped surface and the outer cylindrical case wall to be used as a second electrode. Connectors may be used to stack two or more toroidal cells together by connecting substantially the entire surface area of the first electrode of a first cell to substantially the entire surface area of the second electrode of a second cell. The central cavity of each toroidal cell may be used as a conduit for pumping a fluid through the toroidal cell to thereby cool the cell.

7 CFR 1030.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1030.15 Section 1030.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE UPPER MIDWEST MARKETING AREA Order Regulating Handling Definitions § 1030.15 Fluid milk product. See § 1000.15. ...

7 CFR 1032.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1032.15 Section 1032.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Definitions § 1032.15 Fluid milk product. See § 1000.15. ...

7 CFR 1001.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1001.15 Section 1001.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order Regulating Handling Definitions § 1001.15 Fluid milk product. See § 1000.15. ...

7 CFR 1131.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1131.15 Section 1131.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Definitions § 1131.15 Fluid milk product. See § 1000.15. ...

7 CFR 1033.15 - Fluid milk products.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk products. 1033.15 Section 1033.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Definitions § 1033.15 Fluid milk products. See § 1000.15. ...

7 CFR 1126.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1126.15 Section 1126.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Definitions § 1126.15 Fluid milk product. See § 1000.15. ...

7 CFR 1006.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1006.15 Section 1006.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Definitions § 1006.15 Fluid milk product. See § 1000.15. ...

7 CFR 1006.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1006.15 Section 1006.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Definitions § 1006.15 Fluid milk product. See § 1000.15. ...

7 CFR 1030.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1030.15 Section 1030.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE UPPER MIDWEST MARKETING AREA Order Regulating Handling Definitions § 1030.15 Fluid milk product. See § 1000.15. ...

7 CFR 1124.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1124.15 Section 1124.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Definitions § 1124.15 Fluid milk product. See § 1000.15. ...

7 CFR 1030.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1030.15 Section 1030.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE UPPER MIDWEST MARKETING AREA Order Regulating Handling Definitions § 1030.15 Fluid milk product. See § 1000.15. ...

7 CFR 1006.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1006.15 Section 1006.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Definitions § 1006.15 Fluid milk product. See § 1000.15. ...

7 CFR 1007.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1007.15 Section 1007.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHEAST MARKETING AREA Order Regulating Handling Definitions § 1007.15 Fluid milk product. See § 1000.15. ...

7 CFR 1005.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1005.15 Section 1005.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order Regulating Handling Definitions § 1005.15 Fluid milk product. See § 1000.15. ...

7 CFR 1007.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1007.15 Section 1007.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHEAST MARKETING AREA Order Regulating Handling Definitions § 1007.15 Fluid milk product. See § 1000.15. ...

7 CFR 1005.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1005.15 Section 1005.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order Regulating Handling Definitions § 1005.15 Fluid milk product. See § 1000.15. ...

7 CFR 1032.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1032.15 Section 1032.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Definitions § 1032.15 Fluid milk product. See § 1000.15. ...

7 CFR 1001.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1001.15 Section 1001.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order Regulating Handling Definitions § 1001.15 Fluid milk product. See § 1000.15. ...

7 CFR 1032.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1032.15 Section 1032.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Definitions § 1032.15 Fluid milk product. See § 1000.15. ...

7 CFR 1126.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1126.15 Section 1126.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Definitions § 1126.15 Fluid milk product. See § 1000.15. ...

7 CFR 1005.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1005.15 Section 1005.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order Regulating Handling Definitions § 1005.15 Fluid milk product. See § 1000.15. ...

7 CFR 1001.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1001.15 Section 1001.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order Regulating Handling Definitions § 1001.15 Fluid milk product. See § 1000.15. ...

7 CFR 1007.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1007.15 Section 1007.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHEAST MARKETING AREA Order Regulating Handling Definitions § 1007.15 Fluid milk product. See § 1000.15. ...

7 CFR 1124.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1124.15 Section 1124.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Definitions § 1124.15 Fluid milk product. See § 1000.15. ...

7 CFR 1124.15 - Fluid milk product.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk product. 1124.15 Section 1124.15 Agriculture... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Definitions § 1124.15 Fluid milk product. See § 1000.15. ...

7 CFR 1033.15 - Fluid milk products.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk products. 1033.15 Section 1033.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Definitions § 1033.15 Fluid milk products. See § 1000.15. ...

7 CFR 1126.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1126.15 Section 1126.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Definitions § 1126.15 Fluid milk product. See § 1000.15. ...

7 CFR 1033.15 - Fluid milk products.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 9 2014-01-01 2013-01-01 true Fluid milk products. 1033.15 Section 1033.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Definitions § 1033.15 Fluid milk products. See § 1000.15. ...

7 CFR 1131.15 - Fluid milk product.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Fluid milk product. 1131.15 Section 1131.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Definitions § 1131.15 Fluid milk product. See § 1000.15. ...

7 CFR 1131.15 - Fluid milk product.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Fluid milk product. 1131.15 Section 1131.15... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Definitions § 1131.15 Fluid milk product. See § 1000.15. ...

7 CFR 1005.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1005.15 Section 1005.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order Regulating Handling Definitions § 1005.15 Fluid milk product. See § 1000.15. ...

7 CFR 1124.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1124.15 Section 1124.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Definitions § 1124.15 Fluid milk product. See § 1000.15. ...

7 CFR 1033.15 - Fluid milk products.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk products. 1033.15 Section 1033.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Definitions § 1033.15 Fluid milk products. See § 1000.15. ...

7 CFR 1030.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1030.15 Section 1030.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE UPPER MIDWEST MARKETING AREA Order Regulating Handling Definitions § 1030.15 Fluid milk product. See § 1000.15. ...

7 CFR 1005.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1005.15 Section 1005.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order Regulating Handling Definitions § 1005.15 Fluid milk product. See § 1000.15. ...

7 CFR 1006.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1006.15 Section 1006.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Definitions § 1006.15 Fluid milk product. See § 1000.15. ...

7 CFR 1030.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1030.15 Section 1030.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE UPPER MIDWEST MARKETING AREA Order Regulating Handling Definitions § 1030.15 Fluid milk product. See § 1000.15. ...

7 CFR 1126.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1126.15 Section 1126.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Definitions § 1126.15 Fluid milk product. See § 1000.15. ...

7 CFR 1131.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1131.15 Section 1131.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Definitions § 1131.15 Fluid milk product. See § 1000.15. ...

7 CFR 1007.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1007.15 Section 1007.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHEAST MARKETING AREA Order Regulating Handling Definitions § 1007.15 Fluid milk product. See § 1000.15. ...

7 CFR 1033.15 - Fluid milk products.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk products. 1033.15 Section 1033.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Definitions § 1033.15 Fluid milk products. See § 1000.15. ...

7 CFR 1006.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1006.15 Section 1006.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Definitions § 1006.15 Fluid milk product. See § 1000.15. ...

7 CFR 1032.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1032.15 Section 1032.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Definitions § 1032.15 Fluid milk product. See § 1000.15. ...

7 CFR 1131.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1131.15 Section 1131.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Definitions § 1131.15 Fluid milk product. See § 1000.15. ...

7 CFR 1007.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1007.15 Section 1007.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHEAST MARKETING AREA Order Regulating Handling Definitions § 1007.15 Fluid milk product. See § 1000.15. ...

7 CFR 1126.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1126.15 Section 1126.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Definitions § 1126.15 Fluid milk product. See § 1000.15. ...

7 CFR 1032.15 - Fluid milk product.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Fluid milk product. 1032.15 Section 1032.15 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Definitions § 1032.15 Fluid milk product. See § 1000.15. ...

7 CFR 1124.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1124.15 Section 1124.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Definitions § 1124.15 Fluid milk product. See § 1000.15. ...

7 CFR 1001.15 - Fluid milk product.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 9 2011-01-01 2011-01-01 false Fluid milk product. 1001.15 Section 1001.15... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order Regulating Handling Definitions § 1001.15 Fluid milk product. See § 1000.15. ...

Solid handling valve

DOEpatents

Williams, William R.

1979-01-01

The present invention is directed to a solids handling valve for use in combination with lock hoppers utilized for conveying pulverized coal to a coal gasifier. The valve comprises a fluid-actuated flow control piston disposed within a housing and provided with a tapered primary seal having a recessed seat on the housing and a radially expandable fluid-actuated secondary seal. The valve seals are highly resistive to corrosion, erosion and abrasion by the solids, liquids, and gases associated with the gasification process so as to minimize valve failure.

Fluid handling 2: Surgical applications

NASA Technical Reports Server (NTRS)

Billica, Roger; Young, John; Rushing, Doug; Kizzee, Victor D.

1991-01-01

The methods proposed for managing fluids and particulate debris during minor surgery on Space Station Freedom (SSF) were investigated and demonstrated. A KC-135 parabolic flight test was performed, in which the flight followed the standard 40 parabola profile with 20 to 25 seconds in near-zero gravity in each parabola. The equipment (suction and laminar flow device) was evaluated. While this equipment performed satisfactorily previously in the dental simulation, the purpose of the current flight was to reconfigure the equipment in support of a minor surgical situation in order to evaluate its efficacy and establish clear requirements for the actual flight hardware. To accomplish the study the Health Maintenance Facility medical restraint system was deployed as for surgical use and mannequin suture arm was restrained to its surface. The surgical area was established as for performing minor surgery with standard tray and suture instruments employed.

Modeling and experimental study on near-field acoustic levitation by flexural mode.

PubMed

Liu, Pinkuan; Li, Jin; Ding, Han; Cao, Wenwu

2009-12-01

Near-field acoustic levitation (NFAL) has been used in noncontact handling and transportation of small objects to avoid contamination. We have performed a theoretical analysis based on nonuniform vibrating surface to quantify the levitation force produced by the air film and also conducted experimental tests to verify our model. Modal analysis was performed using ANSYS on the flexural plate radiator to obtain its natural frequency of desired mode, which is used to design the measurement system. Then, the levitation force was calculated as a function of levitation distance based on squeeze gas film theory using measured amplitude and phase distributions on the vibrator surface. Compared with previous fluid-structural analyses using a uniform piston motion, our model based on the nonuniform radiating surface of the vibrator is more realistic and fits better with experimentally measured levitation force.

Leakage Through a Channel Formed by a Gasket, a Sealing Surface, and a Filament Trapped Between Them

NASA Technical Reports Server (NTRS)

Russell, John; Adams, Frederick

1996-01-01

Plumbing for the transport of liquid Hydrogen or liquid Oxygen at the Kennedy Space Center (KSC) is very critical. Every piece of hardware for handling such a hazardous cryogen is subject to testing prior to installation and use. Safe, realistic testing of all such hardware is prohibitively expensive, which leads, perforce, to expidients such as: (1) lead testing with non-flammable tracer fluids (e.g, liquid nitrogen) and (2) leak testing with room temperature tracer fluids (e.g. liquid helium). Such expedients undermine the realism of the tests. If however, one could apply rational fluid dynamics methods to derive a general analytical expression with which one could relate the throughput of gaseous Helium through a given leak channel to the throughput of liquid Hydrogen through the same channel, then one could recover much of the information that one would otherwise forfeit through these expedients. These facts lead to the following questions: (1) What would be an example of a generic flaw in a gasket?; and (2) How can one calculate the flow of fluid in it? The report addresses these questions. It considers a particular leak geometry, namely one formed by a gasket, a sealing surface, and a filament trapped between them (so that the cross section of the leak channel is a flat bottomed curvilinear triangle, two sides of which are circular arcs and which has cusps on all three corners).

A locally refined rectangular grid finite element method - Application to computational fluid dynamics and computational physics

NASA Technical Reports Server (NTRS)

Young, David P.; Melvin, Robin G.; Bieterman, Michael B.; Johnson, Forrester T.; Samant, Satish S.

1991-01-01

The present FEM technique addresses both linear and nonlinear boundary value problems encountered in computational physics by handling general three-dimensional regions, boundary conditions, and material properties. The box finite elements used are defined by a Cartesian grid independent of the boundary definition, and local refinements proceed by dividing a given box element into eight subelements. Discretization employs trilinear approximations on the box elements; special element stiffness matrices are included for boxes cut by any boundary surface. Illustrative results are presented for representative aerodynamics problems involving up to 400,000 elements.

SCISEAL: A CFD code for analysis of fluid dynamic forces in seals

NASA Technical Reports Server (NTRS)

Athavale, Mahesh; Przekwas, Andrzej

1994-01-01

A viewgraph presentation is made of the objectives, capabilities, and test results of the computer code SCISEAL. Currently, the seal code has: a finite volume, pressure-based integration scheme; colocated variables with strong conservation approach; high-order spatial differencing, up to third-order; up to second-order temporal differencing; a comprehensive set of boundary conditions; a variety of turbulence models and surface roughness treatment; moving grid formulation for arbitrary rotor whirl; rotor dynamic coefficients calculated by the circular whirl and numerical shaker methods; and small perturbation capabilities to handle centered and eccentric seals.

Technologies That Enable Accurate and Precise Nano- to Milliliter-Scale Liquid Dispensing of Aqueous Reagents Using Acoustic Droplet Ejection.

PubMed

Sackmann, Eric K; Majlof, Lars; Hahn-Windgassen, Annett; Eaton, Brent; Bandzava, Temo; Daulton, Jay; Vandenbroucke, Arne; Mock, Matthew; Stearns, Richard G; Hinkson, Stephen; Datwani, Sammy S

2016-02-01

Acoustic liquid handling uses high-frequency acoustic signals that are focused on the surface of a fluid to eject droplets with high accuracy and precision for various life science applications. Here we present a multiwell source plate, the Echo Qualified Reservoir (ER), which can acoustically transfer over 2.5 mL of fluid per well in 25-nL increments using an Echo 525 liquid handler. We demonstrate two Labcyte technologies-Dynamic Fluid Analysis (DFA) methods and a high-voltage (HV) grid-that are required to maintain accurate and precise fluid transfers from the ER at this volume scale. DFA methods were employed to dynamically assess the energy requirements of the fluid and adjust the acoustic ejection parameters to maintain a constant velocity droplet. Furthermore, we demonstrate that the HV grid enhances droplet velocity and coalescence at the destination plate. These technologies enabled 5-µL per destination well transfers to a 384-well plate, with accuracy and precision values better than 4%. Last, we used the ER and Echo 525 liquid handler to perform a quantitative polymerase chain reaction (qPCR) assay to demonstrate an application that benefits from the flexibility and larger volume capabilities of the ER. © 2015 Society for Laboratory Automation and Screening.

In-space experiment on thermoacoustic convection heat transfer phenomenon-experiment definition

NASA Technical Reports Server (NTRS)

Parang, M.; Crocker, D. S.

1991-01-01

The definition phase of an in-space experiment in thermoacoustic convection (TAC) heat transfer phenomenon is completed and the results are presented and discussed in some detail. Background information, application and potential importance of TAC in heat transfer processes are discussed with particular focus on application in cryogenic fluid handling and storage in microgravity space environment. Also included are the discussion on TAC space experiment objectives, results of ground support experiments, hardware information, and technical specifications and drawings. The future plans and a schedule for the development of experiment hardware (Phase 1) and flight tests and post-flight analysis (Phase 3/4) are also presented. The specific experimental objectives are rapid heating of a compressible fluid and the measurement of the fluid temperature and pressure and the recording and analysis of the experimental data for the establishment of the importance of TAC heat transfer process. The ground experiments that were completed in support of the experiment definition included fluid temperature measurement by a modified shadowgraph method, surface temperature measurements by thermocouples, and fluid pressure measurements by strain-gage pressure transducers. These experiments verified the feasibility of the TAC in-space experiment, established the relevance and accuracy of the experimental results, and specified the nature of the analysis which will be carried out in the post-flight phase of the report.

A finite area scheme for shallow granular flows on three-dimensional surfaces

NASA Astrophysics Data System (ADS)

Rauter, Matthias

2017-04-01

Shallow granular flow models have become a popular tool for the estimation of natural hazards, such as landslides, debris flows and avalanches. The shallowness of the flow allows to reduce the three-dimensional governing equations to a quasi two-dimensional system. Three-dimensional flow fields are replaced by their depth-integrated two-dimensional counterparts, which yields a robust and fast method [1]. A solution for a simple shallow granular flow model, based on the so-called finite area method [3] is presented. The finite area method is an adaption of the finite volume method [4] to two-dimensional curved surfaces in three-dimensional space. This method handles the three dimensional basal topography in a simple way, making the model suitable for arbitrary (but mildly curved) topography, such as natural terrain. Furthermore, the implementation into the open source software OpenFOAM [4] is shown. OpenFOAM is a popular computational fluid dynamics application, designed so that the top-level code mimics the mathematical governing equations. This makes the code easy to read and extendable to more sophisticated models. Finally, some hints on how to get started with the code and how to extend the basic model will be given. I gratefully acknowledge the financial support by the OEAW project "beyond dense flow avalanches". Savage, S. B. & Hutter, K. 1989 The motion of a finite mass of granular material down a rough incline. Journal of Fluid Mechanics 199, 177-215. Ferziger, J. & Peric, M. 2002 Computational methods for fluid dynamics, 3rd edn. Springer. Tukovic, Z. & Jasak, H. 2012 A moving mesh finite volume interface tracking method for surface tension dominated interfacial fluid flow. Computers & fluids 55, 70-84. Weller, H. G., Tabor, G., Jasak, H. & Fureby, C. 1998 A tensorial approach to computational continuum mechanics using object-oriented techniques. Computers in physics 12(6), 620-631.

21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

Code of Federal Regulations, 2011 CFR

2011-04-01

... highly stable, heat resistant, and nonflammable chemicals. Industrial uses of PCB's include, or did include in the past, their use as electrical transformer and capacitor fluids, heat transfer fluids... Food and Drug Administration have revealed that heat exchange fluids for certain pasteurization...

Scattering of focused ultrasonic beams by cavities in a solid half-space.

PubMed

Rahni, Ehsan Kabiri; Hajzargarbashi, Talieh; Kundu, Tribikram

2012-08-01

The ultrasonic field generated by a point focused acoustic lens placed in a fluid medium adjacent to a solid half-space, containing one or more spherical cavities, is modeled. The semi-analytical distributed point source method (DPSM) is followed for the modeling. This technique properly takes into account the interaction effect between the cavities placed in the focused ultrasonic field, fluid-solid interface and the lens surface. The approximate analytical solution that is available in the literature for the single cavity geometry is very restrictive and cannot handle multiple cavity problems. Finite element solutions for such problems are also prohibitively time consuming at high frequencies. Solution of this problem is necessary to predict when two cavities placed in close proximity inside a solid can be distinguished by an acoustic lens placed outside the solid medium and when such distinction is not possible.

Application of Compressible Volume of Fluid Model in Simulating the Impact and Solidification of Hollow Spherical ZrO2 Droplet on a Surface

NASA Astrophysics Data System (ADS)

Safaei, Hadi; Emami, Mohsen Davazdah; Jazi, Hamidreza Salimi; Mostaghimi, Javad

2017-12-01

Applications of hollow spherical particles in thermal spraying process have been developed in recent years, accompanied by attempts in the form of experimental and numerical studies to better understand the process of impact of a hollow droplet on a surface. During such process, volume and density of the trapped gas inside droplet change. The numerical models should be able to simulate such changes and their consequent effects. The aim of this study is to numerically simulate the impact of a hollow ZrO2 droplet on a flat surface using the volume of fluid technique for compressible flows. An open-source, finite-volume-based CFD code was used to perform the simulations, where appropriate subprograms were added to handle the studied cases. Simulation results were compared with the available experimental data. Results showed that at high impact velocities ( U 0 > 100 m/s), the compression of trapped gas inside droplet played a significant role in the impact dynamics. In such velocities, the droplet splashed explosively. Compressibility effects result in a more porous splat, compared to the corresponding incompressible model. Moreover, the compressible model predicted a higher spread factor than the incompressible model, due to planetary structure of the splat.

Survey of responsible handling of local anesthetic in Indian dental operatory

PubMed Central

Rooban, Thavarajah; Rao, Umadevi Krishnamohan; Joshua, Elizabeth; Ranganathan, Kannan

2013-01-01

Background: Dental operatory requires handling of numerous toxic fluids such as denture acrylic monomer, alcohol and formalin for effective oral care delivery. The efficacy and responsible handling of such fluids has not been analyzed among Indian dentists and this study aims to address this lacunae. Materials and Methods: Closed ended questionnaire was distributed through email to Indian dentists in July 2012. After inclusion/exclusion criteria, 1484 practitioners constituted the study group with a response rate of 52%. Statistics: SPSS® Version 17.0 (SPSS-IBM Inc., IL, USA) was used to carry out statistical analysis. Descriptive statistics were presented. Chi square test was used to identify the association between the parameters; P ≤ 0.05 was considered as statistically significant. Results: Males (80.8%), undergraduates (78%), exclusive practitioners (81.2%), urban practitioners (68.5%) were the predominant respondents. Predominant of the respondents (97%) used local anesthetic (LA) from bottles. Eight percent have encountered instances of injecting formalin instead of LA in their settings. Safe disposal rules and regulations (P ≤ 0.05), opinion on injecting the other fluids instead of LA as a severe negligent act (P ≤ 0.05) were statistically significant between age groups. Educational status did not appear to influence the outcome. Only a third of the respondents were aware of the rules and regulations for safe disposal of empty LA bottles while 49.1% were not aware of them and willing to learn. Discussion: The lacunae in responsible handling of toxic fluids need to be addressed to prevent inadvertent and negligence suits against dentists, highlighting the need through continuing dental education programmes. PMID:24255564

Shear shedding of drops and the use of superhydrophobic surfaces in microgravity: PFC and ground based results

NASA Astrophysics Data System (ADS)

Milne, Andrew; Amirfazli, Alidad

In free fall, the absence of gravity poses many challenges for fluid handling systems. One such example of this is condensers. On earth, the condensed liquid is removed from the tilted condenser plate by gravity forced shedding. In microgravity, proposed solutions include the use of surfaces with gradients in wettability [1], the use of electrowetting [2], and shearing airflow [3]. In this talk, shear shedding results for a variety of surface (hydrophilic to superhydrophobic (extremely water repelling)) will be presented. Surface science and aerodynamics are used to reveal fundamental parameters controlling incipient motion for drops exposed to shearing airflow. It is found that wetting parameters such as contact angle and surface tension are very influential in determining the minimum required air velocity for drop shedding. Based on experimental results for drops of water and hexadecane (0.5-100 l) on PMMA, Teflon, and a superhydrophobic aluminum surface, an exponential function is proposed that relates the critical air velocity for shedding to the ratio of drop base length to projected area. The results for the water systems can be collapsed to a self similar curve by normalization, which also explains results from other researchers. Since shedding from superhydrophobic surfaces (SHS) is seen to be easier compared to other surfaces, the behaviour of SHS is also probed in this talk. SHS have space-based applications to shedding, self cleaning, anti-icing (spacecraft launch/re-entry), anti-fouling, fluid actuation, and decreased fluid friction. The mechanism for SHS is understood to be the existence of an air layer between large portions of the drop and solid. The first concrete visual evidence of this was gained performing a parabolic flight experiment with the ESA. Results of this experi-ment will be discussed, showing the extreme water repelling potential of SHS in microgravity, and demonstrating how the wetting behaviours seen (partial penetration, transition of wetting states, unpredicted contact angle behaviour) affect models of superhydrophobicity and the use of SHS to both space and Earth based applications. 1) Darhuber, A. A.; Troian, S. M. Annual Review of Fluid Mechanics 2005, 425-455. 2) Berthier, J.; Dubois, P.; Clementz, P.; Claustre, P.; Peponnet, C.; Fouillet, Y. Sensors and Actuators A: Physical 2007, 134, 471-479. 3) Milne, A. J. B.; Amirfazli, A. Langmuir 2009, 25, 14155-14164.

Fluid handling and fabric handle profiles of hydroentangled greige cotton and spunbond polypropylene nonwoven topsheets

USDA-ARS?s Scientific Manuscript database

Absorbent nonwoven topsheets are traditionally spunbond (or spunbond-meltblown (SM)) polypropylene nonwoven fabrics, and are used for a wide range of incontinence applications. Here we describe how nonwoven greige cotton demonstrates positive incontinence performance indices suitable for top sheet ...

Ocean Wave Simulation Based on Wind Field

PubMed Central

2016-01-01

Ocean wave simulation has a wide range of applications in movies, video games and training systems. Wind force is the main energy resource for generating ocean waves, which are the result of the interaction between wind and the ocean surface. While numerous methods to handle simulating oceans and other fluid phenomena have undergone rapid development during the past years in the field of computer graphic, few of them consider to construct ocean surface height field from the perspective of wind force driving ocean waves. We introduce wind force to the construction of the ocean surface height field through applying wind field data and wind-driven wave particles. Continual and realistic ocean waves result from the overlap of wind-driven wave particles, and a strategy was proposed to control these discrete wave particles and simulate an endless ocean surface. The results showed that the new method is capable of obtaining a realistic ocean scene under the influence of wind fields at real time rates. PMID:26808718

Ocean Wave Simulation Based on Wind Field.

PubMed

Li, Zhongyi; Wang, Hao

2016-01-01

Ocean wave simulation has a wide range of applications in movies, video games and training systems. Wind force is the main energy resource for generating ocean waves, which are the result of the interaction between wind and the ocean surface. While numerous methods to handle simulating oceans and other fluid phenomena have undergone rapid development during the past years in the field of computer graphic, few of them consider to construct ocean surface height field from the perspective of wind force driving ocean waves. We introduce wind force to the construction of the ocean surface height field through applying wind field data and wind-driven wave particles. Continual and realistic ocean waves result from the overlap of wind-driven wave particles, and a strategy was proposed to control these discrete wave particles and simulate an endless ocean surface. The results showed that the new method is capable of obtaining a realistic ocean scene under the influence of wind fields at real time rates.

21 CFR 500.45 - Use of polychlorinated biphenyls (PCB's) in the production, handling, and storage of animal feed.

Code of Federal Regulations, 2014 CFR

2014-04-01

... include in the past, their use as electrical transformer and capacitor fluids, heat transfer fluids... electrical transformers and condensers containing PCB's in sealed containers. (d) For the purpose of this...

An assessment of computational fluid dynamic techniques in the analysis and design of turbomachinery - The 1990 Freeman Scholar Lecture

NASA Technical Reports Server (NTRS)

Lakshminarayana, B.

1991-01-01

Various computational fluid dynamic techniques are reviewed focusing on the Euler and Navier-Stokes solvers with a brief assessment of boundary layer solutions, and quasi-3D and quasi-viscous techniques. Particular attention is given to a pressure-based method, explicit and implicit time marching techniques, a pseudocompressibility technique for incompressible flow, and zonal techniques. Recommendations are presented with regard to the most appropriate technique for various flow regimes and types of turbomachinery, incompressible and compressible flows, cascades, rotors, stators, liquid-handling, and gas-handling turbomachinery.

Sample Handling and Chemical Kinetics in an Acoustically Levitated Drop Microreactor

PubMed Central

2009-01-01

Accurate measurement of enzyme kinetics is an essential part of understanding the mechanisms of biochemical reactions. The typical means of studying such systems use stirred cuvettes, stopped-flow apparatus, microfluidic systems, or other small sample containers. These methods may prove to be problematic if reactants or products adsorb to or react with the container’s surface. As an alternative approach, we have developed an acoustically-levitated drop reactor eventually intended to study enzyme-catalyzed reaction kinetics related to free radical and oxidative stress chemistry. Microliter-scale droplet generation, reactant introduction, maintenance, and fluid removal are all important aspects in conducting reactions in a levitated drop. A three capillary bundle system has been developed to address these needs. We report kinetic measurements for both luminol chemiluminescence and the reaction of pyruvate with nicotinamide adenine dinucleotide, catalyzed by lactate dehydrogenase, to demonstrate the feasibility of using a levitated drop in conjunction with the developed capillary sample handling system as a microreactor. PMID:19769373

Microfluidics on liquid handling stations (μF-on-LHS): a new industry-compatible microfluidic platform

NASA Astrophysics Data System (ADS)

Kittelmann, Jörg; Radtke, Carsten P.; Waldbaur, Ansgar; Neumann, Christiane; Hubbuch, Jürgen; Rapp, Bastian E.

2014-03-01

Since the early days microfluidics as a scientific discipline has been an interdisciplinary research field with a wide scope of potential applications. Besides tailored assays for point-of-care (PoC) diagnostics, microfluidics has been an important tool for large-scale screening of reagents and building blocks in organic chemistry, pharmaceutics and medical engineering. Furthermore, numerous potential marketable products have been described over the years. However, especially in industrial applications, microfluidics is often considered only an alternative technology for fluid handling, a field which is industrially mostly dominated by large-scale numerically controlled fluid and liquid handling stations. Numerous noteworthy products have dominated this field in the last decade and have been inhibited the widespread application of microfluidics technology. However, automated liquid handling stations and microfluidics do not have to be considered as mutually exclusive approached. We have recently introduced a hybrid fluidic platform combining an industrially established liquid handling station and a generic microfluidic interfacing module that allows probing a microfluidic system (such as an essay or a synthesis array) using the instrumentation provided by the liquid handling station. We term this technology "Microfluidic on Liquid Handling Stations (μF-on-LHS)" - a classical "best of both worlds"- approach that allows combining the highly evolved, automated and industry-proven LHS systems with any type of microfluidic assay. In this paper we show, to the best of our knowledge, the first droplet microfluidics application on an industrial LHS using the μF-on-LHS concept.

NASA's Cryogenic Fluid Management Technology Project

NASA Technical Reports Server (NTRS)

Tramel, Terri L.; Motil, Susan M.

2008-01-01

The Cryogenic Fluid Management (CFM) Project's primary objective is to develop storage, transfer, and handling technologies for cryogens that will support the enabling of high performance cryogenic propulsion systems, lunar surface systems and economical ground operations. Such technologies can significantly reduce propellant launch mass and required on-orbit margins, reduce or even eliminate propellant tank fluid boil-off losses for long term missions, and simplify vehicle operations. This paper will present the status of the specific technologies that the CFM Project is developing. The two main areas of concentration are analysis models development and CFM hardware development. The project develops analysis tools and models based on thermodynamics, hydrodynamics, and existing flight/test data. These tools assist in the development of pressure/thermal control devices (such as the Thermodynamic Vent System (TVS), and Multi-layer insulation); with the ultimate goal being to develop a mature set of tools and models that can characterize the performance of the pressure/thermal control devices incorporated in the design of an entire CFM system with minimal cryogen loss. The project does hardware development and testing to verify our understanding of the physical principles involved, and to validate the performance of CFM components, subsystems and systems. This database provides information to anchor our analytical models. This paper describes some of the current activities of the NASA's Cryogenic Fluid Management Project.

Mars aqueous chemistry experiment

NASA Technical Reports Server (NTRS)

Clark, Benton C.; Mason, Larry W.

1993-01-01

The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

Mars aqueous chemistry experiment

NASA Astrophysics Data System (ADS)

Clark, Benton C.; Mason, Larry W.

1993-06-01

The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

40 CFR Appendix 1 to Subpart A of... - Static Sheen Test

Code of Federal Regulations, 2010 CFR

2010-07-01

... drilling fluids, drill cuttings, produced sand, and well treatment, completion and workover fluids. “Free... drill cuttings or produced sand are introduced into ambient seawater in a container having an air-to... specified. 6. Quality Control Procedures None currently specified. 7. Sample Collection and Handling 7...

Microfluidic viscometers for shear rheology of complex fluids and biofluids

PubMed Central

Wang, William S.; Vanapalli, Siva A.

2016-01-01

The rich diversity of man-made complex fluids and naturally occurring biofluids is opening up new opportunities for investigating their flow behavior and characterizing their rheological properties. Steady shear viscosity is undoubtedly the most widely characterized material property of these fluids. Although widely adopted, macroscale rheometers are limited by sample volumes, access to high shear rates, hydrodynamic instabilities, and interfacial artifacts. Currently, microfluidic devices are capable of handling low sample volumes, providing precision control of flow and channel geometry, enabling a high degree of multiplexing and automation, and integrating flow visualization and optical techniques. These intrinsic advantages of microfluidics have made it especially suitable for the steady shear rheology of complex fluids. In this paper, we review the use of microfluidics for conducting shear viscometry of complex fluids and biofluids with a focus on viscosity curves as a function of shear rate. We discuss the physical principles underlying different microfluidic viscometers, their unique features and limits of operation. This compilation of technological options will potentially serve in promoting the benefits of microfluidic viscometry along with evincing further interest and research in this area. We intend that this review will aid researchers handling and studying complex fluids in selecting and adopting microfluidic viscometers based on their needs. We conclude with challenges and future directions in microfluidic rheometry of complex fluids and biofluids. PMID:27478521

Methods and apparatus for handling or treating particulate material

NASA Technical Reports Server (NTRS)

Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

2009-01-01

An improved draft tube spout fluid bed (DTSFB) mixing, handling, conveying, and treating apparatus and systems, and methods for operating are provided. The apparatus and systems can accept particulate material and pneumatically or hydraulically conveying the material to mix and/or treat the material. In addition to conveying apparatus, a collection and separation apparatus adapted to receive the conveyed particulate material is also provided. The collection apparatus may include an impaction plate against which the conveyed material is directed to improve mixing and/or treatment. The improved apparatus are characterized by means of controlling the operation of the pneumatic or hydraulic transfer to enhance the mixing and/or reacting by controlling the flow of fluids, for example, air, into and out of the apparatus. The disclosed apparatus may be used to mix particulate material, for example, mortar; react fluids with particulate material; coat particulate material, or simply convey particulate material.

High temperature UF6 RF plasma experiments applicable to uranium plasma core reactors

NASA Technical Reports Server (NTRS)

Roman, W. C.

1979-01-01

An investigation was conducted using a 1.2 MW RF induction heater facility to aid in developing the technology necessary for designing a self critical fissioning uranium plasma core reactor. Pure, high temperature uranium hexafluoride (UF6) was injected into an argon fluid mechanically confined, steady state, RF heated plasma while employing different exhaust systems and diagnostic techniques to simulate and investigate some potential characteristics of uranium plasma core nuclear reactors. The development of techniques and equipment for fluid mechanical confinement of RF heated uranium plasmas with a high density of uranium vapor within the plasma, while simultaneously minimizing deposition of uranium and uranium compounds on the test chamber peripheral wall, endwall surfaces, and primary exhaust ducts, is discussed. The material tests and handling techniques suitable for use with high temperature, high pressure, gaseous UF6 are described and the development of complementary diagnostic instrumentation and measurement techniques to characterize the uranium plasma, effluent exhaust gases, and residue deposited on the test chamber and exhaust system components is reported.

Numerical investigation on cryogenic liquid jet under transcritical and supercritical conditions

NASA Astrophysics Data System (ADS)

Li, Liang; Xie, Maozhao; Wei, Wu; Jia, Ming; Liu, Hongsheng

2018-01-01

Cryogenic fluid injection and mixing under transcritical and supercritical conditions is numerically investigated with emphasis on the difference of the mechanism and characteristics between the two injections. A new solver is developed which is capable of handling the nonideality of the equation of state and the anomalies in fluid transport properties and is incorporated into the CFD software OpenFOAM. The new solver has been validated against available experimental data and exhibits a good performance. Computational results indicates that the differences between transcritical and supercritical injections are mainly induced by the pseudo-boiling phenomenon, resulting in that the transcritical jet has a longer cold liquid core and an isothermal expansion occurs at the surface of the cold core. The thickness of the supercritical mixing layer and its increase value along the jet direction are greater than its transcritical counterpart. The high-temperature jet whose initial temperature is above the pseudo-boiling temperature has the ability of enhancing the mixing of the jet with the surrounding gas.

Fluid Acquisition and Resupply Experiment (FARE-I) flight results

NASA Astrophysics Data System (ADS)

Dominick, Sam M.; Driscoll, Susan L.

1993-06-01

The Fluid Acquisition and Resupply Experiment, (FARE) is a Shuttle middeck-mounted experiment to demonstrate techniques for handling liquids in zero gravity for operations such as refueling spacecraft in orbit. The first flight took place on STS 53 launched December 2, 1992. Eight tests were performed during the mission and the experiment achieved 100 percent mission success. The second flight will be on STS 57, scheduled for launch in June 1993. The objective of FARE I was to demonstrate techniques for controlling the position of the liquid and gas within a tank during refilling and to better understand the operation of screen-type surface tension devices used to drain tanks in zero gravity. Tests were performed to demonstrate tank refilling, low gravity propellant slosh, and expulsion efficiency of the screen device. Expulsion efficiencies of 97 percent - 98 percent were demonstrated under a variety of flowrates and accelerations. Final fill levels of 60 percent to 80 percent were achieved during the vented fill tests.

Feasibility study: Atmospheric general circulation experiment, volume 1

NASA Technical Reports Server (NTRS)

Homsey, R. J. (Editor)

1981-01-01

The atmospheric general circulation experiment (AGCE) uses a rotating fluid flow cell assembly. The key technical areas affecting the feasibility of the design and operation of the AGCE are investigated. The areas investigated include materials for the flow cell assembly, thermal design, high voltage power supply design, effective retrieval and handling of experiment data and apparatus configuration. Several materials, DMSO and m-tolunitrile, were selected as candidate fluids for the flow cell principally for their high dielectric constant which permits the high voltage power supply design to be held to 15 kV and still simulate terrestrial gravity. Achievement of a low dissipation factor in the fluid to minimize internal heating from the applied electrical field depends strongly on purification and handling procedures. The use of sapphire as the outer hemisphere for the flow cell provides excellent viewing conditions without a significant impact on attaining the desired thermal gradients. Birefringent effects from sapphire can be held to acceptably low limits. Visualization of flow fluid is achieved through the motion of a dot matrix formed by photochromic dyes. Two dyes found compatible with the candidate fluids are spiropyran and triarylmethane. The observation of the dot motion is accomplished using a flying spot scanner.

Current development in microfluidic immunosensing chip.

PubMed

Henares, Terence G; Mizutani, Fumio; Hisamoto, Hideaki

2008-03-17

This review accounts for the current development in microfluidic immunosensing chips. The basic knowledge of immunoassay in relation to its microfluidic material substrate, fluid handling and detection mode are briefly discussed. Here, we mainly focused on the surface modification, antibody immobilization, detection, signal enhancement and multiple analyte sensing. Some of the clinically important currently implemented on the microfluidic immunoassay chips are C-reactive protein (CRP), prostate specific antigen (PSA), ferritin, vascular endothelial growth factor (VEGF), myoglobin (Myo), cardiac troponin T (cTnT), cardiac troponin I (cTnI), and creatine kinase-cardiac muscle isoform (CK-MB). The emerging microfludic immunosensor technology may be a promising prospect that can propel the improvement of clinical and medical diagnosis.

Extension of Generalized Fluid System Simulation Program's Fluid Property Database

NASA Technical Reports Server (NTRS)

Patel, Kishan

2011-01-01

This internship focused on the development of additional capabilities for the General Fluid Systems Simulation Program (GFSSP). GFSSP is a thermo-fluid code used to evaluate system performance by a finite volume-based network analysis method. The program was developed primarily to analyze the complex internal flow of propulsion systems and is capable of solving many problems related to thermodynamics and fluid mechanics. GFSSP is integrated with thermodynamic programs that provide fluid properties for sub-cooled, superheated, and saturation states. For fluids that are not included in the thermodynamic property program, look-up property tables can be provided. The look-up property tables of the current release version can only handle sub-cooled and superheated states. The primary purpose of the internship was to extend the look-up tables to handle saturated states. This involves a) generation of a property table using REFPROP, a thermodynamic property program that is widely used, and b) modifications of the Fortran source code to read in an additional property table containing saturation data for both saturated liquid and saturated vapor states. Also, a method was implemented to calculate the thermodynamic properties of user-fluids within the saturation region, given values of pressure and enthalpy. These additions required new code to be written, and older code had to be adjusted to accommodate the new capabilities. Ultimately, the changes will lead to the incorporation of this new capability in future versions of GFSSP. This paper describes the development and validation of the new capability.

Discrete Element Modeling of Triboelectrically Charged Particles

NASA Technical Reports Server (NTRS)

Hogue, Michael D.; Calle, Carlos I.; Weitzman, Peter S.; Curry, David R.

2008-01-01

Tribocharging of particles is common in many processes including fine powder handling and mixing, printer toner transport and dust extraction. In a lunar environment with its high vacuum and lack of water, electrostatic forces are an important factor to consider when designing and operating equipment. Dust mitigation and management is critical to safe and predictable performance of people and equipment. The extreme nature of lunar conditions makes it difficult and costly to carry out experiments on earth which are necessary to better understand how particles gather and transfer charge between each other and with equipment surfaces. DEM (Discrete Element Modeling) provides an excellent virtual laboratory for studying tribocharging of particles as well as for design of devices for dust mitigation and for other purposes related to handling and processing of lunar regolith. Theoretical and experimental work has been performed pursuant to incorporating screened Coulombic electrostatic forces into EDEM, a commercial DEM software package. The DEM software is used to model the trajectories of large numbers of particles for industrial particulate handling and processing applications and can be coupled with other solvers and numerical models to calculate particle interaction with surrounding media and force fields. While simple Coulombic force between two particles is well understood, its operation in an ensemble of particles is more complex. When the tribocharging of particles and surfaces due to frictional contact is also considered, it is necessary to consider longer range of interaction of particles in response to electrostatic charging. The standard DEM algorithm accounts for particle mechanical properties and inertia as a function of particle shape and mass. If fluid drag is neglected, then particle dynamics are governed by contact between particles, between particles and equipment surfaces and gravity forces. Consideration of particle charge and any tribocharging and electric field effects requires calculation of the forces due to these effects.

Conceptual design of a closed loop nutrient solution delivery system for CELSS implementation in a micro-gravity environment

NASA Technical Reports Server (NTRS)

Schwartzkopf, Steven H.; Oleson, Mel W.; Cullingford, Hatice S.

1990-01-01

Described here are the results of a study to develop a conceptual design for an experimental closed loop fluid handling system capable of monitoring, controlling, and supplying nutrient solution to higher plants. The Plant Feeder Experiment (PFE) is designed to be flight tested in a microgravity environment. When flown, the PFX will provide information on both the generic problems of microgravity fluid handling and the specific problems associated with the delivery of the nutrient solution in a microgravity environment. The experimental hardware is designed to fit into two middeck lockers on the Space Shuttle, and incorporates several components that have previously been flight tested.

A deformable surface model for real-time water drop animation.

PubMed

Zhang, Yizhong; Wang, Huamin; Wang, Shuai; Tong, Yiying; Zhou, Kun

2012-08-01

A water drop behaves differently from a large water body because of its strong viscosity and surface tension under the small scale. Surface tension causes the motion of a water drop to be largely determined by its boundary surface. Meanwhile, viscosity makes the interior of a water drop less relevant to its motion, as the smooth velocity field can be well approximated by an interpolation of the velocity on the boundary. Consequently, we propose a fast deformable surface model to realistically animate water drops and their flowing behaviors on solid surfaces. Our system efficiently simulates water drop motions in a Lagrangian fashion, by reducing 3D fluid dynamics over the whole liquid volume to a deformable surface model. In each time step, the model uses an implicit mean curvature flow operator to produce surface tension effects, a contact angle operator to change droplet shapes on solid surfaces, and a set of mesh connectivity updates to handle topological changes and improve mesh quality over time. Our numerical experiments demonstrate a variety of physically plausible water drop phenomena at a real-time rate, including capillary waves when water drops collide, pinch-off of water jets, and droplets flowing over solid materials. The whole system performs orders-of-magnitude faster than existing simulation approaches that generate comparable water drop effects.

Handling and storage of human body fluids for analysis of extracellular vesicles

PubMed Central

Yuana, Yuana; Böing, Anita N.; Grootemaat, Anita E.; van der Pol, Edwin; Hau, Chi M.; Cizmar, Petr; Buhr, Egbert; Sturk, Auguste; Nieuwland, Rienk

2015-01-01

Because procedures of handling and storage of body fluids affect numbers and composition of extracellular vesicles (EVs), standardization is important to ensure reliable and comparable measurements of EVs in a clinical environment. We aimed to develop standard protocols for handling and storage of human body fluids for EV analysis. Conditions such as centrifugation, single freeze–thaw cycle, effect of time delay between blood collection and plasma preparation and storage were investigated. Plasma is the most commonly studied body fluid in EV research. We mainly focused on EVs originating from platelets and erythrocytes and investigated the behaviour of these 2 types of EVs independently as well as in plasma samples of healthy subjects. EVs in urine and saliva were also studied for comparison. All samples were analysed simultaneously before and after freeze–thawing by resistive pulse sensing, nanoparticle tracking analysis, conventional flow cytometry (FCM) and transmission (scanning) electron microscopy. Our main finding is that the effect of centrifugation markedly depends on the cellular origin of EVs. Whereas erythrocyte EVs remain present as single EVs after centrifugation, platelet EVs form aggregates, which affect their measured concentration in plasma. Single erythrocyte and platelet EVs are present mainly in the range of 100–200 nm, far below the lower limit of what can be measured by conventional FCM. Furthermore, the effects of single freeze–thaw cycle, time delay between blood collection and plasma preparation up to 1 hour and storage up to 1 year are insignificant (p>0.05) on the measured concentration and diameter of EVs from erythrocyte and platelet concentrates and EVs in plasma, urine and saliva. In conclusion, in standard protocols for EV studies, centrifugation to isolate EVs from collected body fluids should be avoided. Freezing and storage of collected body fluids, albeit their insignificant effects, should be performed identically for comparative EV studies and to create reliable biorepositories. PMID:26563735

Handling and storage of human body fluids for analysis of extracellular vesicles.

PubMed

Yuana, Yuana; Böing, Anita N; Grootemaat, Anita E; van der Pol, Edwin; Hau, Chi M; Cizmar, Petr; Buhr, Egbert; Sturk, Auguste; Nieuwland, Rienk

2015-01-01

Because procedures of handling and storage of body fluids affect numbers and composition of extracellular vesicles (EVs), standardization is important to ensure reliable and comparable measurements of EVs in a clinical environment. We aimed to develop standard protocols for handling and storage of human body fluids for EV analysis. Conditions such as centrifugation, single freeze-thaw cycle, effect of time delay between blood collection and plasma preparation and storage were investigated. Plasma is the most commonly studied body fluid in EV research. We mainly focused on EVs originating from platelets and erythrocytes and investigated the behaviour of these 2 types of EVs independently as well as in plasma samples of healthy subjects. EVs in urine and saliva were also studied for comparison. All samples were analysed simultaneously before and after freeze-thawing by resistive pulse sensing, nanoparticle tracking analysis, conventional flow cytometry (FCM) and transmission (scanning) electron microscopy. Our main finding is that the effect of centrifugation markedly depends on the cellular origin of EVs. Whereas erythrocyte EVs remain present as single EVs after centrifugation, platelet EVs form aggregates, which affect their measured concentration in plasma. Single erythrocyte and platelet EVs are present mainly in the range of 100-200 nm, far below the lower limit of what can be measured by conventional FCM. Furthermore, the effects of single freeze-thaw cycle, time delay between blood collection and plasma preparation up to 1 hour and storage up to 1 year are insignificant (p>0.05) on the measured concentration and diameter of EVs from erythrocyte and platelet concentrates and EVs in plasma, urine and saliva. In conclusion, in standard protocols for EV studies, centrifugation to isolate EVs from collected body fluids should be avoided. Freezing and storage of collected body fluids, albeit their insignificant effects, should be performed identically for comparative EV studies and to create reliable biorepositories.

Abnormal MRI in a patient with 'headache with neurological deficits and CSF lymphocytosis (HaNDL)'.

PubMed

Yilmaz, A; Kaleagasi, H; Dogu, O; Kara, E; Ozge, A

2010-05-01

A 27-year-old woman was admitted to the Emergency Department with right upper-extremity numbness and mild weakness followed by a bifrontal throbbing headache for 30 min, which was similar to a headache lasting for 12 h that had occurred 3 days ago. Laboratory tests were unremarkable except for cerebrospinal fluid (CSF) lymphocytic pleocytosis. On the following day, a headache episode with left hemiparesis and hemihypoaesthesia, left hemifield visio-spatial inattention, anosagnosia and confusion recurred. The headache was diagnosed as headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) syndrome according to the criteria of the second edition of the International Classification of Headache Disorders. Simultaneously performed magnetic resonance imaging (MRI) revealed swelling of the grey matter, CSF enhancement in the sulci of the right temporal and occipital regions and hypoperfusion of the same brain regions. During the following 10 days two more similar episodes recurred and during the ensuing 12 months the patient remained headache free. Neuroimaging findings of the HaNDL syndrome are always thought as virtually normal. MRI abnormalities in our patient have not been reported in HaNDL syndrome previously, although they have been reported in hemiplegic migraine patients before. The findings in our case suggest that hemiplegic migraine and HaNDL syndrome may share a common pathophysiological pathway resulting in similar imaging findings and neurological symptoms.

Development of liquid handling techniques in microgravity

NASA Technical Reports Server (NTRS)

Antar, Basil N.

1995-01-01

A large number of experiments dealing with protein crystal growth and also with growth of crystals from solution require complicated fluid handling procedures including filling of empty containers with liquids, mixing of solutions, and stirring of liquids. Such procedures are accomplished in a straight forward manner when performed under terrestrial conditions in the laboratory. However, in the low gravity environment of space, such as on board the Space Shuttle or an Earth-orbiting space station, these procedures sometimes produced entirely undesirable results. Under terrestrial conditions, liquids usually completely separate from the gas due to the buoyancy effects of Earth's gravity. Consequently, any gas pockets that are entrained into the liquid during a fluid handling procedure will eventually migrate towards the top of the vessel where they can be removed. In a low gravity environment any folded gas bubble will remain within the liquid bulk indefinitely at a location that is not known a priori resulting in a mixture of liquid and vapor.

The detection of blood on dental surgery surfaces and equipment following dental hygiene treatment.

PubMed

McColl, E; Bagg, J; Winning, S

1994-01-22

The Kastle-Meyer technique, a forensic test for blood, has been employed to assess the frequency and potential routes of contamination by blood between patients, staff and equipment during routine dental hygiene treatment. Fifty treatment sessions were studied and units were cleaned between patients according to the current hospital protocol. The surfaces most frequently contaminated after treatment were the 3-in-1 syringe buttons (40%), protective bibs (22%), tap handles (20%), light handles (18%) and operating cart handles (16%). Following cleaning of the units, the surfaces remaining contaminated were the 3-in-1 syringes (10%), tap handles (4%) and cart handles (2%). Modifications to the cross-infection control protocol have been made to eliminate these sources of contamination.

Bayesian Calibration of Thermodynamic Databases and the Role of Kinetics

NASA Astrophysics Data System (ADS)

Wolf, A. S.; Ghiorso, M. S.

2017-12-01

Self-consistent thermodynamic databases of geologically relevant materials (like Berman, 1988; Holland and Powell, 1998, Stixrude & Lithgow-Bertelloni 2011) are crucial for simulating geological processes as well as interpreting rock samples from the field. These databases form the backbone of our understanding of how fluids and rocks interact at extreme planetary conditions. Considerable work is involved in their construction from experimental phase reaction data, as they must self-consistently describe the free energy surfaces (including relative offsets) of potentially hundreds of interacting phases. Standard database calibration methods typically utilize either linear programming or least squares regression. While both produce a viable model, they suffer from strong limitations on the training data (which must be filtered by hand), along with general ignorance of many of the sources of experimental uncertainty. We develop a new method for calibrating high P-T thermodynamic databases for use in geologic applications. The model is designed to handle pure solid endmember and free fluid phases and can be extended to include mixed solid solutions and melt phases. This new calibration effort utilizes Bayesian techniques to obtain optimal parameter values together with a full family of statistically acceptable models, summarized by the posterior. Unlike previous efforts, the Bayesian Logistic Uncertain Reaction (BLUR) model directly accounts for both measurement uncertainties and disequilibrium effects, by employing a kinetic reaction model whose parameters are empirically determined from the experiments themselves. Thus, along with the equilibrium free energy surfaces, we also provide rough estimates of the activation energies, entropies, and volumes for each reaction. As a first application, we demonstrate this new method on the three-phase aluminosilicate system, illustrating how it can produce superior estimates of the phase boundaries by incorporating constraints from all available data, while automatically handling variable data quality due to a combination of measurement errors and kinetic effects.

Generating Inviscid and Viscous Fluid-Flow Simulations over an Aircraft Surface Using a Fluid-Flow Mesh

NASA Technical Reports Server (NTRS)

Rodriguez, David L. (Inventor); Sturdza, Peter (Inventor)

2013-01-01

Fluid-flow simulation over a computer-generated aircraft surface is generated using inviscid and viscous simulations. A fluid-flow mesh of fluid cells is obtained. At least one inviscid fluid property for the fluid cells is determined using an inviscid fluid simulation that does not simulate fluid viscous effects. A set of intersecting fluid cells that intersects the aircraft surface are identified. One surface mesh polygon of the surface mesh is identified for each intersecting fluid cell. A boundary-layer prediction point for each identified surface mesh polygon is determined. At least one boundary-layer fluid property for each boundary-layer prediction point is determined using the at least one inviscid fluid property of the corresponding intersecting fluid cell and a boundary-layer simulation that simulates fluid viscous effects. At least one updated fluid property for at least one fluid cell is determined using the at least one boundary-layer fluid property and the inviscid fluid simulation.

Programmable lab-on-a-chip system for single cell analysis

NASA Astrophysics Data System (ADS)

Thalhammer, S.

2009-05-01

The collection, selection, amplification and detection of minimum genetic samples became a part of everyday life in medical and biological laboratories, to analyze DNA-fragments of pathogens, patient samples and traces on crime scenes. About a decade ago, a handful of researchers began discussing an intriguing idea. Could the equipment needed for everyday chemistry and biology procedures be shrunk to fit on a chip in the size of a fingernail? Miniature devices for, say, analysing DNA and proteins should be faster and cheaper than conventional versions. Lab-on-a-chip is an advanced technology that integrates a microfluidic system on a microscale chip device. The "laboratory" is created by means of channels, mixers, reservoirs, diffusion chambers, integrated electrodes, pumps, valves and more. With lab-ona- chip technology, complete laboratories on a square centimetre can be created. Here, a multifunctional programmable Lab-on-a-Chip driven by nanofluidics and controlled by surface acoustic waves (SAW) is presented. This system combines serial DNA-isolation-, amplification- and array-detection-process on a modified glass-platform. The fluid actuation is controlled via SAW by interdigital transducers implemented in the chemical modified chip surface. The chemical surface modification allows fluid handling in the sub-microliter range. Minute amount of sample material is extracted by laser-based microdissection out of e.g. histological sections at the single cell level. A few picogram of genetic material are isolated and transferred via a low-pressure transfer system (SPATS) onto the chip. Subsequently the genetic material inside single droplets, which behave like "virtual" beaker, is transported to the reaction and analysis centers on the chip surface via surface acoustic waves, mainly known as noise dumping filters in mobile phones. At these "biological reactors" the genetic material is processed, e.g. amplified via polymerase chain reaction methods, and genetically characterized.

Simplified thermodynamic functions for vapor-liquid phase separation and fountain effect pumps

NASA Technical Reports Server (NTRS)

Yuan, S. W. K.; Hepler, W. A.; Frederking, T. H. K.

1984-01-01

He-4 fluid handling devices near 2 K require novel components for non-Newtonian fluid transport in He II. Related sizing of devices has to be based on appropriate thermophysical property functions. The present paper presents simplified equilibrium state functions for porous media components which serve as vapor-liquid phase separators and fountain effect pumps.

30 CFR 250.459 - What are the safety requirements for drilling fluid-handling areas?

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Drilling Fluid Requirements § 250.459 What are the safety... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What are the safety requirements for drilling...

30 CFR 250.459 - What are the safety requirements for drilling fluid-handling areas?

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Drilling Fluid Requirements § 250.459 What are the safety... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What are the safety requirements for drilling...

30 CFR 250.459 - What are the safety requirements for drilling fluid-handling areas?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Drilling Fluid Requirements § 250.459 What are... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What are the safety requirements for drilling...

30 CFR 250.459 - What are the safety requirements for drilling fluid-handling areas?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What are the safety requirements for drilling... OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Drilling Fluid Requirements § 250.459 What are the safety requirements for...

30 CFR 250.459 - What are the safety requirements for drilling fluid-handling areas?

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Drilling Fluid Requirements § 250.459 What are the safety... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What are the safety requirements for drilling...

Spray Combustion Modeling with VOF and Finite-Rate Chemistry

NASA Technical Reports Server (NTRS)

Chen, Yen-Sen; Shang, Huan-Min; Liaw, Paul; Wang, Ten-See

1996-01-01

A spray atomization and combustion model is developed based on the volume-of-fluid (VOF) transport equation with finite-rate chemistry model. The gas-liquid interface mass, momentum and energy conservation laws are modeled by continuum surface force mechanisms. A new solution method is developed such that the present VOF model can be applied for all-speed range flows. The objectives of the present study are: (1) to develop and verify the fractional volume-of-fluid (VOF) cell partitioning approach into a predictor-corrector algorithm to deal with multiphase (gas-liquid) free surface flow problems; (2) to implement the developed unified algorithm in a general purpose computational fluid dynamics (CFD) code, Finite Difference Navier-Stokes (FDNS), with droplet dynamics and finite-rate chemistry models; and (3) to demonstrate the effectiveness of the present approach by simulating benchmark problems of jet breakup/spray atomization and combustion. Modeling multiphase fluid flows poses a significant challenge because a required boundary must be applied to a transient, irregular surface that is discontinuous, and the flow regimes considered can range from incompressible to highspeed compressible flows. The flow-process modeling is further complicated by surface tension, interfacial heat and mass transfer, spray formation and turbulence, and their interactions. The major contribution of the present method is to combine the novel feature of the Volume of Fluid (VOF) method and the Eulerian/Lagrangian method into a unified algorithm for efficient noniterative, time-accurate calculations of multiphase free surface flows valid at all speeds. The proposed method reformulated the VOF equation to strongly couple two distinct phases (liquid and gas), and tracks droplets on a Lagrangian frame when spray model is required, using a unified predictor-corrector technique to account for the non-linear linkages through the convective contributions of VOF. The discontinuities within the sharp interface will be modeled as a volume force to avoid stiffness. Formations of droplets, tracking of droplet dynamics and modeling of the droplet breakup/evaporation, are handled through the same unified predictor-corrector procedure. Thus the new algorithm is non-iterative and is flexible for general geometries with arbitrarily complex topology in free surfaces. The FDNS finite-difference Navier-Stokes code is employed as the baseline of the current development. Benchmark test cases of shear coaxial LOX/H2 liquid jet with atomization/combustion and impinging jet test cases are investigated in the present work. Preliminary data comparisons show good qualitative agreement between data and the present analysis. It is indicative from these results that the present method has great potential to become a general engineering design analysis and diagnostics tool for problems involving spray combustion.

A sharp interface method for compressible liquid–vapor flow with phase transition and surface tension

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fechter, Stefan, E-mail: stefan.fechter@iag.uni-stuttgart.de; Munz, Claus-Dieter, E-mail: munz@iag.uni-stuttgart.de; Rohde, Christian, E-mail: Christian.Rohde@mathematik.uni-stuttgart.de

The numerical approximation of non-isothermal liquid–vapor flow within the compressible regime is a difficult task because complex physical effects at the phase interfaces can govern the global flow behavior. We present a sharp interface approach which treats the interface as a shock-wave like discontinuity. Any mixing of fluid phases is avoided by using the flow solver in the bulk regions only, and a ghost-fluid approach close to the interface. The coupling states for the numerical solution in the bulk regions are determined by the solution of local two-phase Riemann problems across the interface. The Riemann solution accounts for the relevantmore » physics by enforcing appropriate jump conditions at the phase boundary. A wide variety of interface effects can be handled in a thermodynamically consistent way. This includes surface tension or mass/energy transfer by phase transition. Moreover, the local normal speed of the interface, which is needed to calculate the time evolution of the interface, is given by the Riemann solution. The interface tracking itself is based on a level-set method. The focus in this paper is the description of the two-phase Riemann solver and its usage within the sharp interface approach. One-dimensional problems are selected to validate the approach. Finally, the three-dimensional simulation of a wobbling droplet and a shock droplet interaction in two dimensions are shown. In both problems phase transition and surface tension determine the global bulk behavior.« less

NASA Tech Briefs, November 2012

NASA Technical Reports Server (NTRS)

2012-01-01

The topics include: Visual System for Browsing, Analysis, and Retrieval of Data (ViSBARD); Time-Domain Terahertz Computed Axial Tomography NDE System; Adaptive Sampling of Time Series During Remote Exploration; A Tracking Sun Photometer Without Moving Parts; Surface Temperature Data Analysis; Modular, Autonomous Command and Data Handling Software with Built-In Simulation and Test; In-Situ Wire Damage Detection System; Amplifier Module for 260-GHz Band Using Quartz Waveguide Transitions; Wideband Agile Digital Microwave Radiometer; Buckyball Nucleation of HiPco Tubes; FACT, Mega-ROSA, SOLAROSA; An Integrated, Layered-Spinel Composite Cathode for Energy Storage Applications; Engineered Multifunctional Surfaces for Fluid Handling; Polyolefin-Based Aerogels; Adjusting Permittivity by Blending Varying Ratios of SWNTs; Gravity-Assist Mechanical Simulator for Outreach; Concept for Hydrogen-Impregnated Nanofiber/Photovoltaic Cargo Stowage System; DROP: Durable Reconnaissance and Observation Platform; Developing Physiologic Models for Emergency Medical Procedures Under Microgravity; Spectroscopic Chemical Analysis Methods and Apparatus; Low Average Sidelobe Slot Array Antennas for Radiometer Applications; Motion-Corrected 3D Sonic Anemometer for Tethersondes and Other Moving Platforms; Water Treatment Systems for Long Spaceflights; Microchip Non-Aqueous Capillary Electrophoresis (MicronNACE) Method to Analyze Long-Chain Primary Amines; Low-Cost Phased Array Antenna for Sounding Rockets, Missiles, and Expendable Launch Vehicles; Mars Science Laboratory Engineering Cameras; Seismic Imager Space Telescope; Estimating Sea Surface Salinity and Wind Using Combined Passive and Active L-Band Microwave Observations; A Posteriori Study of a DNS Database Describing Super critical Binary-Species Mixing; Scalable SCPPM Decoder; QuakeSim 2.0; HURON (HUman and Robotic Optimization Network) Multi-Agent Temporal Activity Planner/Scheduler; MPST Software: MoonKommand

Improved thermodynamic modeling of the no-vent fill process and correlation with experimental data

NASA Technical Reports Server (NTRS)

Taylor, William J.; Chato, David J.

1991-01-01

The United States' plans to establish a permanent manned presence in space and to explore the Solar System created the need to efficiently handle large quantities of subcritical cryogenic fluids, particularly propellants such as liquid hydrogen and liquid oxygen, in low- to zero-gravity environments. One of the key technologies to be developed for fluid handling is the ability to transfer the cryogens between storage and spacecraft tanks. The no-vent fill method was identified as one way to perform this transfer. In order to understand how to apply this method, a model of the no-vent fill process is being developed and correlated with experimental data. The verified models then can be used to design and analyze configurations for tankage and subcritical fluid depots. The development of an improved macroscopic thermodynamic model is discussed of the no-vent fill process and the analytical results from the computer program implementation of the model are correlated with experimental results for two different test tanks.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anthony Leonard; Phillippe Chatelain; Michael Rebel

Heavy ground vehicles, especially those involved in long-haul freight transportation, consume a significant part of our nation's energy supply. it is therefore of utmost importance to improve their efficiency, both to reduce emissions and to decrease reliance on imported oil. At highway speeds, more than half of the power consumed by a typical semi truck goes into overcoming aerodynamic drag, a fraction which increases with speed and crosswind. Thanks to better tools and increased awareness, recent years have seen substantial aerodynamic improvements by the truck industry, such as tractor/trailer height matching, radiator area reduction, and swept fairings. However, there remainsmore » substantial room for improvement as understanding of turbulent fluid dynamics grows. The group's research effort focused on vortex particle methods, a novel approach for computational fluid dynamics (CFD). Where common CFD methods solve or model the Navier-Stokes equations on a grid which stretches from the truck surface outward, vortex particle methods solve the vorticity equation on a Lagrangian basis of smooth particles and do not require a grid. They worked to advance the state of the art in vortex particle methods, improving their ability to handle the complicated, high Reynolds number flow around heavy vehicles. Specific challenges that they have addressed include finding strategies to accurate capture vorticity generation and resultant forces at the truck wall, handling the aerodynamics of spinning bodies such as tires, application of the method to the GTS model, computation time reduction through improved integration methods, a closest point transform for particle method in complex geometrics, and work on large eddy simulation (LES) turbulence modeling.« less

Optics-Integrated Microfluidic Platforms for Biomolecular Analyses

PubMed Central

Bates, Kathleen E.; Lu, Hang

2016-01-01

Compared with conventional optical methods, optics implemented on microfluidic chips provide small, and often much cheaper ways to interrogate biological systems from the level of single molecules up to small model organisms. The optical probing of single molecules has been used to investigate the mechanical properties of individual biological molecules; however, multiplexing of these measurements through microfluidics and nanofluidics confers many analytical advantages. Optics-integrated microfluidic systems can significantly simplify sample processing and allow a more user-friendly experience; alignments of on-chip optical components are predetermined during fabrication and many purely optical techniques are passively controlled. Furthermore, sample loss from complicated preparation and fluid transfer steps can be virtually eliminated, a particularly important attribute for biological molecules at very low concentrations. Excellent fluid handling and high surface area/volume ratios also contribute to faster detection times for low abundance molecules in small sample volumes. Although integration of optical systems with classical microfluidic analysis techniques has been limited, microfluidics offers a ready platform for interrogation of biophysical properties. By exploiting the ease with which fluids and particles can be precisely and dynamically controlled in microfluidic devices, optical sensors capable of unique imaging modes, single molecule manipulation, and detection of minute changes in concentration of an analyte are possible. PMID:27119629

Raman spectroscopic signature of vaginal fluid and its potential application in forensic body fluid identification.

PubMed

Sikirzhytskaya, Aliaksandra; Sikirzhytski, Vitali; Lednev, Igor K

2012-03-10

Traces of human body fluids, such as blood, saliva, sweat, semen and vaginal fluid, play an increasingly important role in forensic investigations. However, a nondestructive, easy and rapid identification of body fluid traces at the scene of a crime has not yet been developed. The obstacles have recently been addressed in our studies, which demonstrated the considerable potential of Raman spectroscopy. In this study, we continued to build a full library of body fluid spectroscopic signatures. The problems concerning vaginal fluid stain identification were addressed using Raman spectroscopy coupled with advanced statistical analysis. Calculated characteristic Raman and fluorescent spectral components were used to build a multidimensional spectroscopic signature of vaginal fluid, which demonstrated good specificity and was able to handle heterogeneous samples from different donors. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Traces of illegal drugs on body surfaces: indicator for consumption or dealing?

NASA Astrophysics Data System (ADS)

Aberl, Franz; Bonenberger, Johannes; Berg, Ralf-Peter; Zimmermann, Rudolph; Sachs, Hans W.

1997-01-01

Customs investigation and drug enforcement services are interest in a rapid and reliable identification of smugglers and dealers. In contrast workplace testing and traffic controls are aiming at the detection of intoxicated persons via the determination of illegal narcotics in body fluids like urine or blood. DRUGWIPE is a pen size, test strip based immunochemical detector for narcotic contaminations on surfaces. It is extremely simple to apply and takes about two minutes to read test results without depending upon any further technical means. This paper describes the applicability of DRUGWIPE to identify drug smugglers or dealers as well as consumers. With respect to the situation and the initial suspicion the test indicates handling as well as consumption. In cooperation with the Institute for Legal Medicine in Munich suspicious drivers were examined with DRUGWIPE for the abuse of illegal narcotics. Test results from this test series are presented and compared with the results from the blood or urine analysis. The question whether the detected traces of illegal narcotics on the body surface of suspicious drivers are combing transpiration or external contamination are discussed.

Comments on Frequency Swept Rotating Input Perturbation Techniques and Identification of the Fluid Force Models in Rotor/bearing/seal Systems and Fluid Handling Machines

NASA Technical Reports Server (NTRS)

Muszynska, Agnes; Bently, Donald E.

1991-01-01

Perturbation techniques used for identification of rotating system dynamic characteristics are described. A comparison between two periodic frequency-swept perturbation methods applied in identification of fluid forces of rotating machines is presented. The description of the fluid force model identified by inputting circular periodic frequency-swept force is given. This model is based on the existence and strength of the circumferential flow, most often generated by the shaft rotation. The application of the fluid force model in rotor dynamic analysis is presented. It is shown that the rotor stability is an entire rotating system property. Some areas for further research are discussed.

Water and sodium balance in space.

PubMed

Drummer, C; Norsk, P; Heer, M

2001-09-01

We have previously shown that fluid balances and body fluid regulation in microgravity (microG) differ from those on Earth (Drummer et al, Eur J Physiol 441:R66-R72, 2000). Arriving in microG leads to a redistribution of body fluid-composed of a shift of fluid to the upper part of the body and an exaggerated extravasation very early in-flight. The mechanisms for the increased vascular permeability are not known. Evaporation, oral hydration, and urinary fluid excretion, the major components of water balance, are generally diminished during space flight compared with conditions on Earth. Nevertheless, cumulative water balance and total body water content are stable during flight if hydration, nutritional energy supply, and protection of muscle mass are at an acceptable level. Recent water balance data disclose that the phenomenon of an absolute water loss during space flight, which has often been reported in the past, is not a consequence of the variable microG. The handling of sodium, however, is considerably affected by microG. Sodium-retaining endocrine systems, such as renin-aldosterone and catecholamines, are much more activated during microG than on Earth. Despite a comparable oral sodium supply, urinary sodium excretion is diminished and a considerable amount of sodium is retained-without accumulating in the intravascular space. An enormous storage capacity for sodium in the extravascular space and a mechanism that allows the dissociation between water and sodium handling likely contribute to the fluid balance adaptation in weightlessness.

Immersed boundary methods for simulating fluid-structure interaction

NASA Astrophysics Data System (ADS)

Sotiropoulos, Fotis; Yang, Xiaolei

2014-02-01

Fluid-structure interaction (FSI) problems commonly encountered in engineering and biological applications involve geometrically complex flexible or rigid bodies undergoing large deformations. Immersed boundary (IB) methods have emerged as a powerful simulation tool for tackling such flows due to their inherent ability to handle arbitrarily complex bodies without the need for expensive and cumbersome dynamic re-meshing strategies. Depending on the approach such methods adopt to satisfy boundary conditions on solid surfaces they can be broadly classified as diffused and sharp interface methods. In this review, we present an overview of the fundamentals of both classes of methods with emphasis on solution algorithms for simulating FSI problems. We summarize and juxtapose different IB approaches for imposing boundary conditions, efficient iterative algorithms for solving the incompressible Navier-Stokes equations in the presence of dynamic immersed boundaries, and strong and loose coupling FSI strategies. We also present recent results from the application of such methods to study a wide range of problems, including vortex-induced vibrations, aquatic swimming, insect flying, human walking and renewable energy. Limitations of such methods and the need for future research to mitigate them are also discussed.

Review on microfluidic paper-based analytical devices towards commercialisation.

PubMed

Akyazi, Tugce; Basabe-Desmonts, Lourdes; Benito-Lopez, Fernando

2018-02-25

Paper-based analytical devices introduce an innovative platform technology for fluid handling and analysis, with wide range of applications, promoting low cost, ease of fabrication/operation and equipment independence. This review gives a general overview on the fabrication techniques reported to date, revealing and discussing their weak points as well as the newest approaches in order to overtake current mass production limitations and therefore commercialisation. Moreover, this review aims especially to highlight novel technologies appearing in literature for the effective handling and controlling of fluids. The lack of flow control is the main problem of paper-based analytical devices, which generates obstacles for marketing and slows down the transition of paper devices from the laboratory into the consumers' hands. Copyright © 2017 Elsevier B.V. All rights reserved.

Cooling apparatus and couplings therefor

NASA Technical Reports Server (NTRS)

Lomax, Curtis (Inventor); Webbon, Bruce (Inventor)

1993-01-01

The present invention relates generally to the field of thermal transfer and, more specifically, to a direct-interface, fusible heat sink for non-venting, regenerable, and self-contained thermal regulation. A quick connect coupling includes a male and a female portion. The female portion is frozen in a container of solid-phase coolant fluid, i.e., water, so that passages in the housing are blocked by ice initially. The ice is melted by direct interface with liquid coolant fluid delivered from the male portion. The present invention has advantages in that the phase change material remains sealed at all times, including during regeneration. Also, it uses quick-disconnect couplings that allow the phase change material to completely fill the container and is easily handled in microgravity without spills, leakage, or handling of phase change material.

A Computational Model of Coupled Multiphase Flow and Geomechanics to Study Fault Slip and Induced Seismicity

NASA Astrophysics Data System (ADS)

Juanes, R.; Jha, B.

2014-12-01

The coupling between subsurface flow and geomechanical deformation is critical in the assessment of the environmental impacts of groundwater use, underground liquid waste disposal, geologic storage of carbon dioxide, and exploitation of shale gas reserves. In particular, seismicity induced by fluid injection and withdrawal has emerged as a central element of the scientific discussion around subsurface technologies that tap into water and energy resources. Here we present a new computational approach to model coupled multiphase flow and geomechanics of faulted reservoirs. We represent faults as surfaces embedded in a three-dimensional medium by using zero-thickness interface elements to accurately model fault slip under dynamically evolving fluid pressure and fault strength. We incorporate the effect of fluid pressures from multiphase flow in the mechanical stability of faults and employ a rigorous formulation of nonlinear multiphase geomechanics that is capable of handling strong capillary effects. We develop a numerical simulation tool by coupling a multiphase flow simulator with a mechanics simulator, using the unconditionally stable fixed-stress scheme for the sequential solution of two-way coupling between flow and geomechanics. We validate our modeling approach using several synthetic, but realistic, test cases that illustrate the onset and evolution of earthquakes from fluid injection and withdrawal. We also present the application of the coupled flow-geomechanics simulation technology to the post mortem analysis of the Mw=5.1, May 2011 Lorca earthquake in south-east Spain, and assess the potential that the earthquake was induced by groundwater extraction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This volume contains the interim change notice for the safety operation procedure for hot cell. It covers the master-slave manipulators, dry waste removal, cell transfers, hoists, cask handling, liquid waste system, and physical characterization of fluids.

Flexible Electrostatic Technology for Capture and Handling Project

NASA Technical Reports Server (NTRS)

Keys, Andrew; Bryan, Tom; Horwitz, Chris; Rakoczy, John; Waggoner, Jason

2015-01-01

To NASA unfunded & planned missions: This new capability to sense proximity, flexibly align to, and attractively grip and capture practically any object in space without any pre-designed physical features or added sensors or actuators will enable or enhance many of MSFC's strategic emphasis areas in space transportation, and space systems such as: 1. A Flexible Electrostatic gripper can enable the capture, gripping and releasing of an extraterrestrial sample of different minerals or a sample canister (metallic or composite) without requiring a handle or grapple fixture.(B) 2. Flexible self-aligning in-space capture/soft docking or berthing of ISS resupply vehicles, pressurized modules, or nodes for in-space assembly and shielding, radiator, and solar Array deployment for space habitats (C) 3. The flexible electrostatic gripper when combined with a simple steerable extendible boom can grip, position, and release objects of various shapes and materials with low mass and power without any prior handles or physical accommodations or surface contamination for ISS experiment experiments and in-situ repair.(F)(G) 4. The Dexterous Docking concept previously proposed to allow simple commercial resupply ships to station-keep and capture either ISS or an Exploration vehicle for supply or fluid transfer lacked a self-sensing, compliant, soft capture gripper like FETCH that could retract and attach to a CBM. (I) 5. To enable a soft capture and de-orbit of a piece of orbital debris will require self-aligning gripping and holding an object wherever possible (thermal coverings or shields of various materials, radiators, solar arrays, antenna dishes) with little or no residual power while adding either drag or active low level thrust.(K) 6. With the scalability of the FETCH technology, small satellites can be captured and handled or can incorporate FETCH gripper to dock to and handle other small vehicles and larger objects for de-orbiting or mitigating Orbital debris (L) 7. Many of previous MSFC and NASA proposals or concepts can now be realized or simplified by the development of the this initial and future FETCH grippers including commercial resupply, Exploration vehicle assembly, Satellite servicing, and orbital debris removal since a major part of these missions is to align to and capture some handle. Completed Project (2013 - 2014) Flexible Electrostatic Technology for Capture & Handling Project Center Innovation Fund: MSFC CIF Program | Space Technology Mission Directorate (STMD) For more information visit techport.nasa.gov Some NASA technology projects are smaller (for example SBIR/STTR, NIAC and Center Innovation Fund), and will have less content than other, larger projects. Newly created projects may not sensors or injection of permanent adhesives. With gripping forces estimated between 0.5 and 2.5 pounds per square inch or 70-300 lb./sq. ft. of surface contact, the FETCH can turn-on and turn-off rapidly and repeatedly to enable sample handling, soft docking, in-space assembly, and precision relocation for accurate anchor adhesion.

Computer code for gas-liquid two-phase vortex motions: GLVM

NASA Technical Reports Server (NTRS)

Yeh, T. T.

1986-01-01

A computer program aimed at the phase separation between gas and liquid at zero gravity, induced by vortex motion, is developed. It utilizes an explicit solution method for a set of equations describing rotating gas-liquid flows. The vortex motion is established by a tangential fluid injection. A Lax-Wendroff two-step (McCormack's) numerical scheme is used. The program can be used to study the fluid dynamical behavior of the rotational two-phase fluids in a cylindrical tank. It provides a quick/easy sensitivity test on various parameters and thus provides the guidance for the design and use of actual physical systems for handling two-phase fluids.

Ball assisted device for analytical surface sampling

DOEpatents

ElNaggar, Mariam S; Van Berkel, Gary J; Covey, Thomas R

2015-11-03

A system for sampling a surface includes a sampling probe having a housing and a socket, and a rolling sampling sphere within the socket. The housing has a sampling fluid supply conduit and a sampling fluid exhaust conduit. The sampling fluid supply conduit supplies sampling fluid to the sampling sphere. The sampling fluid exhaust conduit has an inlet opening for receiving sampling fluid carried from the surface by the sampling sphere. A surface sampling probe and a method for sampling a surface are also disclosed.

Controlled microfluidic interfaces for microsensors

NASA Astrophysics Data System (ADS)

Jiang, H.

2009-02-01

Lab on a chip has found many applications in biological and chemical analysis, including pathogen detections. Because these labs on chips involve handling of fluids at the microscale, surface tension profoundly affects the behavior and performance of these systems. Through careful engineering, controlled liquid-liquid or liquid-gas interfaces at the microscale can be formed and used in many interesting applications. In this talk, I will present our work on applying such interfaces to microsensing. These interfaces are created at hydrophobic-hydrophilic boundaries formed within microfluidic channels and pinned by surface tension. We have designed and fabricated a few microsensing techniques including chemical and biological sensing using dissolvable micromembranes in microchannels, chemical and biological sensing at liquid crystals interfacing either air or aqueous solutions, and collection of gaseous samples and aerosols through air-liquid microfludic interfaces. I will next introduce on-chip microlenses and microlens arrays for optical detection, including smart and adaptive liquid microlenses actuated by stimuli-responsive hydrogels, and liquid microlenses in situ formed within microfluidic channels via pneumatic control of droplets.

A new 3D immersed boundary method for non-Newtonian fluid-structure-interaction with application

NASA Astrophysics Data System (ADS)

Zhu, Luoding

2017-11-01

Motivated by fluid-structure-interaction (FSI) phenomena in life sciences (e.g., motions of sperm and cytoskeleton in complex fluids), we introduce a new immersed boundary method for FSI problems involving non-Newtonian fluids in three dimensions. The non-Newtonian fluids are modelled by the FENE-P model (including the Oldroyd-B model as an especial case) and numerically solved by a lattice Boltzmann scheme (the D3Q7 model). The fluid flow is modelled by the lattice Boltzmann equations and numerically solved by the D3Q19 model. The deformable structure and the fluid-structure-interaction are handled by the immersed boundary method. As an application, we study a FSI toy problem - interaction of an elastic plate (flapped at its leading edge and restricted nowhere else) with a non-Newtonian fluid in a 3D flow. Thanks to the support of NSF-DMS support under research Grant 1522554.

Hydrostatic bearings for a turbine fluid flow metering device

DOEpatents

Fincke, James R.

1982-01-01

A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

Hydrostatic bearings for a turbine fluid flow metering device

DOEpatents

Fincke, J.R.

1982-05-04

A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion. 3 figs.

Heterogeneous catalysis in complex, condensed reaction media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cantu, David C.; Wang, Yang-Gang; Yoon, Yeohoon

Many reactions required for the upgrading of biomass into fuels and chemicals—hydrogenation, hydrodeoxygenation, hydrocracking—are ostensibly similar to those practiced in the upgrading of petroleum into fuels. But, repurposing hydroprocessing catalysts from refinery operations to treat bio-oil has proved to be unsatisfactory. New catalysts are needed because the composition of the biogenic reactants differs from that of petroleum-derived feedstocks (e.g. the low concentration of sulfur in cellulose-derived biomass precludes use of metal sulfide catalysts unless sulfur is added to the reaction stream). New processes are needed because bio-oils oligomerize rapidly, forming intractable coke and “gunk”, at temperatures so low that themore » desired upgrading reactions are impractically slow, and so low that the bio-oil upgrading must be handled as a condensed fluid. Ideally, the new catalysts and processes would exploit the properties of the multiple phases present in condensed bio-oil, notably the polarizability and structure of the fluid near a catalyst’s surface in the cybotactic region. The results of preliminary modeling of the cybotactic region of different catalyst surfaces in the hydrogenation of phenol suggest that Pd catalysts supported on hydrophilic surfaces are more active than catalysts based on lipophilic supports because the former serve to enhance the concentration of the phenol in the vicinity of the Pd. The effect stems from thermodynamics, not the rate of mass transport. This work was supported by the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Bioenergy Technologies Office. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.« less

Hydrostatic bearings for a turbine fluid flow metering device

DOEpatents

Fincke, J.R.

1980-05-02

A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

Supercritical fluid extraction and direct fluid injection mass spectrometry for the determination of trichothecene mycotoxins in wheat samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalinoski, H.T.; Udseth, H.R.; Wright, B.W.

1986-10-01

The application of on-line supercritical fluid extraction with chemical ionization mass spectrometry and collision induced dissociation tandem mass spectrometry for the rapid identification of parts-per-million levels of several trichothecene mycotoxins is demonstrated. Supercritical carbon dioxide is shown to allow identification of mycotoxins with minimum sample handling in complex natural matrices (e.g., wheat). Tandem mass spectrometry techniques are employed for unambiguous identification of compounds of varying polarity, and false positives from isobaric compounds are avoided. Capillary column supercritical fluid chromatography-mass spectrometry of a supercritical fluid extract of the same sample was also performed and detection limits in the parts-per-billion range appearmore » feasible.« less

Large scale cryogenic fluid systems testing

NASA Technical Reports Server (NTRS)

1992-01-01

NASA Lewis Research Center's Cryogenic Fluid Systems Branch (CFSB) within the Space Propulsion Technology Division (SPTD) has the ultimate goal of enabling the long term storage and in-space fueling/resupply operations for spacecraft and reusable vehicles in support of space exploration. Using analytical modeling, ground based testing, and on-orbit experimentation, the CFSB is studying three primary categories of fluid technology: storage, supply, and transfer. The CFSB is also investigating fluid handling, advanced instrumentation, and tank structures and materials. Ground based testing of large-scale systems is done using liquid hydrogen as a test fluid at the Cryogenic Propellant Tank Facility (K-site) at Lewis' Plum Brook Station in Sandusky, Ohio. A general overview of tests involving liquid transfer, thermal control, pressure control, and pressurization is given.

Intravenous Fluid Mixing in Normal Gravity, Partial Gravity, and Microgravity: Down-Selection of Mixing Methods

NASA Technical Reports Server (NTRS)

Niederhaus, Charles E.; Miller, Fletcher J.

2008-01-01

The missions envisioned under the Vision for Space Exploration will require development of new methods to handle crew medical care. Medications and intravenous (IV) fluids have been identified as one area needing development. Storing certain medications and solutions as powders or concentrates can both increase the shelf life and reduce the overall mass and volume of medical supplies. The powders or concentrates would then be mixed in an IV bag with Sterile Water for Injection produced in situ from the potable water supply. Fluid handling in microgravity is different than terrestrial settings, and requires special consideration in the design of equipment. This document describes the analyses and down-select activities used to identify the IV mixing method to be developed that is suitable for ISS and exploration missions. The chosen method is compatible with both normal gravity and microgravity, maintains sterility of the solution, and has low mass and power requirements. The method will undergo further development, including reduced gravity aircraft experiments and computations, in order to fully develop the mixing method and associated operational parameters.

Supercritical fluid technology: concepts and pharmaceutical applications.

PubMed

Deshpande, Praful Balavant; Kumar, G Aravind; Kumar, Averineni Ranjith; Shavi, Gopal Venkatesh; Karthik, Arumugam; Reddy, Meka Sreenivasa; Udupa, Nayanabhirama

2011-01-01

In light of environmental apprehension, supercritical fluid technology (SFT) exhibits excellent opportunities to accomplish key objectives in the drug delivery sector. Supercritical fluid extraction using carbon dioxide (CO(2)) has been recognized as a green technology. It is a clean and versatile solvent with gas-like diffusivity and liquid-like density in the supercritical phase, which has provided an excellent alternative to the use of chemical solvents. The present commentary provides an overview of different techniques using supercritical fluids and their future opportunity for the drug delivery industry. Some of the emerging applications of SFT in pharmaceuticals, such as particle design, drug solubilization, inclusion complex, polymer impregnation, polymorphism, drug extraction process, and analysis, are also covered in this review. The data collection methods are based on the recent literature related to drug delivery systems using SFT platforms. SFT has become a much more versatile and environmentally attractive technology that can handle a variety of complicated problems in pharmaceuticals. This cutting-edge technology is growing predominantly to surrogate conventional unit operations in relevance to the pharmaceutical production process. Supercritical fluid technology has recently drawn attention in the field of pharmaceuticals. It is a distinct conception that utilizes the solvent properties of supercritical fluids above their critical temperature and pressure, where they exhibit both liquid-like and gas-like properties, which can enable many pharmaceutical applications. For example, the liquid-like properties provide benefits in extraction processes of organic solvents or impurities, drug solubilization, and polymer plasticization, and the gas-like features facilitate mass transfer processes. It has become a much more versatile and environmentally attractive technology that can handle a variety of complicated problems in pharmaceuticals. This review is focused on different techniques that use supercritical fluids and their opportunities for the pharmaceutical sector.

Supercritical fluids as alternative, safe, food-processing media: an overview.

PubMed

Da Cruz Francisco, José; Szwajcer Dey, Estera

2003-01-01

The continuous growth of world population and its concentration in the urban areas require food supplies that are continuous, sufficient and of good quality. To resolve this problem techniques have been developed for increasing food quantity and quality. The techniques are applied throughout the food chain from production, conservation and during distribution to the consumers (from "the field to the fork"). During handling of food, chemicals are often deliberately added to achieve improved processing and better quality. This is one of the main reasons food undergoes different kinds of contamination. This overview focuses on the application of supercritical fluids as media for handling food materials during processing with the perspective of reducing chemical contamination of food. Examples of developmental applications of this technique and on research work in process are presented. Emphasis is given to extraction and biotransformation techniques.

A scintillator purification plant and fluid handling system for SNO+

NASA Astrophysics Data System (ADS)

Ford, Richard J.

2015-08-01

A large capacity purification plant and fluid handling system has been constructed for the SNO+ neutrino and double-beta decay experiment, located 6800 feet underground at SNOLAB, Canada. SNO+ is a refurbishment of the SNO detector to fill the acrylic vessel with liquid scintillator based on Linear Alkylbenzene (LAB) and 2 g/L PPO, and also has a phase to load natural tellurium into the scintillator for a double-beta decay experiment with 130Te. The plant includes processes multi-stage dual-stream distillation, column water extraction, steam stripping, and functionalized silica gel adsorption columns. The plant also includes systems for preparing the scintillator with PPO and metal-loading the scintillator for double-beta decay exposure. We review the basis of design, the purification principles, specifications for the plant, and the construction and installations. The construction and commissioning status is updated.

Method and apparatus for monitoring and measuring the surface tension of a fluid using fiber optics

DOEpatents

Abraham, Bernard M.; Ketterson, John B.; Bohanon, Thomas M.; Mikrut, John M.

1994-01-01

A non-contact method and apparatus for measuring and monitoring the surface of a fluid using fiber optics and interferometric detection to permit measurement mechanical characteristics' fluid surfaces. The apparatus employs an alternating electric field gradient for generating a capillary wave on the surface of the fluid. A fiber optic coupler and optical fiber directs a portion of a laser beam onto the surface of the fluid, another portion of the laser beam onto the photo sensor, and directs light reflected from the surface of the fluid onto the photo sensor. The output of the photo sensor is processed and coupled to a phase sensitive detector to permit measurement of phase shift between the drive signal creating the capillary wave and the detected signal. This phase shift information is then used to determine mechanical properties of the fluid surface such as surface tension, surface elasticity, and surface inhomogeneity. The resulting test structure is easily made compact, portable, and easy to align and use.

Evolutionary space station fluids management strategies

NASA Technical Reports Server (NTRS)

1989-01-01

Results are summarized for an 11-month study to define fluid storage and handling strategies and requirements for various specific mission case studies and their associated design impacts on the Space Station. There are a variety of fluid users which require a variety of fluids and use rates. Also, the cryogenic propellants required for NASA's STV, Planetary, and Code Z missions are enormous. The storage methods must accommodate fluids ranging from a high pressure gas or supercritical state fluid to a sub-cooled liquid (and superfluid helium). These requirements begin in the year 1994, reach a maximum of nearly 1800 metric tons in the year 2004, and trail off to the year 2018, as currently planned. It is conceivable that the cryogenic propellant needs for the STV and/or Lunar mission models will be met by LTCSF LH2/LO2 tanksets attached to the SS truss structure. Concepts and corresponding transfer and delivery operations have been presented for STV propellant provisioning from the SS. A growth orbit maneuvering vehicle (OMV) and associated servicing capability will be required to move tanksets from delivery launch vehicles to the SS or co-orbiting platforms. Also, appropriate changes to the software used for OMV operation are necessary to allow for the combined operation of the growth OMV. To support fluid management activities at the Space Station for the experimental payloads and propellant provisioning, there must be truss structure space allocated for fluid carriers and propellant tanksets, and substantial beam strengthening may be required. The Station must have two Mobile Remote Manipulator Systems (MRMS) and the growth OMV propellant handling operations for the STV at the SS. Propellant needs for the Planetary Initiatives and Code Z mission models will most likely be provided by co-orbiting propellant platform(s). Space Station impacts for Code Z mission fluid management activities will be minimal.

SPH modeling of fluid-solid interaction for dynamic failure analysis of fluid-filled thin shells

NASA Astrophysics Data System (ADS)

Caleyron, F.; Combescure, A.; Faucher, V.; Potapov, S.

2013-05-01

This work concerns the prediction of failure of a fluid-filled tank under impact loading, including the resulting fluid leakage. A water-filled steel cylinder associated with a piston is impacted by a mass falling at a prescribed velocity. The cylinder is closed at its base by an aluminum plate whose characteristics are allowed to vary. The impact on the piston creates a pressure wave in the fluid which is responsible for the deformation of the plate and, possibly, the propagation of cracks. The structural part of the problem is modeled using Mindlin-Reissner finite elements (FE) and Smoothed Particle Hydrodynamics (SPH) shells. The modeling of the fluid is also based on an SPH formulation. The problem involves significant fluid-structure interactions (FSI) which are handled through a master-slave-based method and the pinballs method. Numerical results are compared to experimental data.

Microscale fluid transport using optically controlled marangoni effect

DOEpatents

Thundat, Thomas G [Knoxville, TN; Passian, Ali [Knoxville, TN; Farahi, Rubye H [Oak Ridge, TN

2011-05-10

Low energy light illumination and either a doped semiconductor surface or a surface-plasmon supporting surface are used in combination for manipulating a fluid on the surface in the absence of any applied electric fields or flow channels. Precise control of fluid flow is achieved by applying focused or tightly collimated low energy light to the surface-fluid interface. In the first embodiment, with an appropriate dopant level in the semiconductor substrate, optically excited charge carriers are made to move to the surface when illuminated. In a second embodiment, with a thin-film noble metal surface on a dispersive substrate, optically excited surface plasmons are created for fluid manipulation. This electrode-less optical control of the Marangoni effect provides re-configurable manipulations of fluid flow, thereby paving the way for reprogrammable microfluidic devices.

Magnetic heat pump flow director

NASA Technical Reports Server (NTRS)

Howard, Frank S. (Inventor)

1995-01-01

A fluid flow director is disclosed. The director comprises a handle body and combed-teeth extending from one side of the body. The body can be formed of a clear plastic such as acrylic. The director can be used with heat exchangers such as a magnetic heat pump and can minimize the undesired mixing of fluid flows. The types of heat exchangers can encompass both heat pumps and refrigerators. The director can adjust the fluid flow of liquid or gas along desired flow directions. A method of applying the flow director within a magnetic heat pump application is also disclosed where the comb-teeth portions of the director are inserted into the fluid flow paths of the heat pump.

Visual detection of nucleic acids based on Mie scattering and the magnetophoretic effect.

PubMed

Zhao, Zichen; Chen, Shan; Ho, John Kin Lim; Chieng, Ching-Chang; Chen, Ting-Hsuan

2015-12-07

Visual detection of nucleic acid biomarkers is a simple and convenient approach to point-of-care applications. However, issues of sensitivity and the handling of complex bio-fluids have posed challenges. Here we report on a visual method detecting nucleic acids using Mie scattering of polystyrene microparticles and the magnetophoretic effect. Magnetic microparticles (MMPs) and polystyrene microparticles (PMPs) were surface-functionalised with oligonucleotide probes, which can hybridise with target oligonucleotides in juxtaposition and lead to the formation of MMPs-targets-PMPs sandwich structures. Using an externally applied magnetic field, the magnetophoretic effect attracts the sandwich structure to the sidewall, which reduces the suspended PMPs and leads to a change in the light transmission via the Mie scattering. Based on the high extinction coefficient of the Mie scattering (∼3 orders of magnitude greater than that of the commonly used gold nanoparticles), our results showed the limit of detection to be 4 pM using a UV-Vis spectrometer or 10 pM by direct visual inspection. Meanwhile, we also demonstrated that this method is compatible with multiplex assays and detection in complex bio-fluids, such as whole blood or a pool of nucleic acids, without purification in advance. With a simplified operation procedure, low instrumentation requirement, high sensitivity and compatibility with complex bio-fluids, this method provides an ideal solution for visual detection of nucleic acids in resource-limited settings.

Data handling and representation of freeform surfaces

NASA Astrophysics Data System (ADS)

Steinkopf, Ralf; Dick, Lars; Kopf, Tino; Gebhardt, Andreas; Risse, Stefan; Eberhardt, Ramona

2011-10-01

Freeform surfaces enable innovative optics. They are not limited by axis symmetry and hence they are almost free in design. They are used to reduce the installation space and enhance the performance of optical elements. State of the art optical design tools are computing with powerful algorithms to simulate freeform surfaces. Even new mathematical approaches are under development /1/. In consequence, new optical designs /2/ are pushing the development of manufacturing processes consequently and novel types of datasets have to proceed through the process chain /3/. The complexity of these data is the huge challenge for the data handling. Because of the asymmetrical and 3-dimensional surfaces of freeforms, large data volumes have to be created, trimmed, extended and fitted. All these processes must be performed without losing the accuracy of the original design data. Additionally, manifold types of geometries results in different kinds of mathematical representations of freeform surfaces and furthermore the used CAD/CAM tools are dealing with a set of spatial transport formats. These are all reasons why manufacture-oriented approaches for the freeform data handling are not yet sufficiently developed. This paper suggests a classification of freeform surfaces based on the manufacturing methods which are offered by diamond machining. The different manufacturing technologies, ranging from servo-turning to shaping, require a differentiated approach for the data handling process. The usage of analytical descriptions in form of splines and polynomials as well as the application of discrete descriptions like point clouds is shown in relation to the previously made classification. Advantages and disadvantages of freeform representations are discussed. Aspects of the data handling in between different process steps are pointed out and suitable exchange formats for freeform data are proposed. The described approach offers the possibility for efficient data handling from optical design to systems in novel optics.

Hazards and Safeguards of High Pressure Hydraulic Fatigue Testing

DTIC Science & Technology

1990-07-01

rew e I&64aN neem mde tliF by block mumber) The creation and transfer of hydraulic pressure at the 690-MPa (100,000-psi) level is in itself hazardous...our hydraulic test systems using fluids capable of flow up to the test pressure. Up to 690 MPa (100,000 psi), synthetic oils especially formulated for...HANDLING Our most frequent injury problem has been in handling the large tubular specimens. These are inherently smooth, round, oil -coated, and heavy. For

Method and apparatus for monitoring and measuring the surface tension of a fluid using fiber optics

DOEpatents

Abraham, B.M.; Ketterson, J.B.; Bohanon, T.M.; Mikrut, J.M.

1994-04-12

A non-contact method and apparatus are described for measuring and monitoring the surface of a fluid using fiber optics and interferometric detection to permit measurement of mechanical characteristics of fluid surfaces. The apparatus employs an alternating electric field gradient for generating a capillary wave on the surface of the fluid. A fiber optic coupler and optical fiber directs a portion of a laser beam onto the surface of the fluid, another portion of the laser beam onto the photo sensor, and directs light reflected from the surface of the fluid onto the photo sensor. The output of the photo sensor is processed and coupled to a phase sensitive detector to permit measurement of phase shift between the drive signal creating the capillary wave and the detected signal. This phase shift information is then used to determine mechanical properties of the fluid surface such as surface tension, surface elasticity, and surface inhomogeneity. The resulting test structure is easily made compact, portable, and easy to align and use. 4 figures.

Adaptive particle-based pore-level modeling of incompressible fluid flow in porous media: a direct and parallel approach

NASA Astrophysics Data System (ADS)

Ovaysi, S.; Piri, M.

2009-12-01

We present a three-dimensional fully dynamic parallel particle-based model for direct pore-level simulation of incompressible viscous fluid flow in disordered porous media. The model was developed from scratch and is capable of simulating flow directly in three-dimensional high-resolution microtomography images of naturally occurring or man-made porous systems. It reads the images as input where the position of the solid walls are given. The entire medium, i.e., solid and fluid, is then discretized using particles. The model is based on Moving Particle Semi-implicit (MPS) technique. We modify this technique in order to improve its stability. The model handles highly irregular fluid-solid boundaries effectively. It takes into account viscous pressure drop in addition to the gravity forces. It conserves mass and can automatically detect any false connectivity with fluid particles in the neighboring pores and throats. It includes a sophisticated algorithm to automatically split and merge particles to maintain hydraulic connectivity of extremely narrow conduits. Furthermore, it uses novel methods to handle particle inconsistencies and open boundaries. To handle the computational load, we present a fully parallel version of the model that runs on distributed memory computer clusters and exhibits excellent scalability. The model is used to simulate unsteady-state flow problems under different conditions starting from straight noncircular capillary tubes with different cross-sectional shapes, i.e., circular/elliptical, square/rectangular and triangular cross-sections. We compare the predicted dimensionless hydraulic conductances with the data available in the literature and observe an excellent agreement. We then test the scalability of our parallel model with two samples of an artificial sandstone, samples A and B, with different volumes and different distributions (non-uniform and uniform) of solid particles among the processors. An excellent linear scalability is obtained for sample B that has more uniform distribution of solid particles leading to a superior load balancing. The model is then used to simulate fluid flow directly in REV size three-dimensional x-ray images of a naturally occurring sandstone. We analyze the quality and consistency of the predicted flow behavior and calculate absolute permeability, which compares well with the available network modeling and Lattice-Boltzmann permeabilities available in the literature for the same sandstone. We show that the model conserves mass very well and is stable computationally even at very narrow fluid conduits. The transient- and the steady-state fluid flow patterns are presented as well as the steady-state flow rates to compute absolute permeability. Furthermore, we discuss the vital role of our adaptive particle resolution scheme in preserving the original pore connectivity of the samples and their narrow channels through splitting and merging of fluid particles.

Influence on grip of knife handle surface characteristics and wearing protective gloves.

PubMed

Claudon, Laurent

2006-11-01

Ten subjects were asked to apply maximum torques on knife handles with either their bare hand or their hand wearing a Kevlar fibre protective glove. Four knife handles (2 roughnesses, 2 hardnesses) were tested. Surface electromyograms of 6 upper limb and shoulder muscles were recorded and subject opinions on both knife handle hardness and friction in the hand were also assessed. The results revealed the significant influence of wearing gloves (p<0.0001), knife type (p<0.0005) and handle hardness (p<0.005) on the applied torque. Wearing Kevlar fibre gloves greatly increased the torque independently of the other two parameters. Under the bare hand condition, a 90 degrees ShA slightly rough handle provided the greatest torque. Subject opinion agreed with the observed effects on recorded torque values except for the hardness factor, for which a preference for the 70 degrees ShA value over the 90 degrees ShA value emerged.

Magneto-rheological suspensions for improving ground vehicle's ride comfort, stability, and handling

NASA Astrophysics Data System (ADS)

Ahmadian, Mehdi

2017-10-01

A state-of-the-art discussion on the applications of magneto-rheological (MR) suspensions for improving ride comfort, handling, and stability in ground vehicles is discussed for both road and rail applications. A historical perspective on the discovery and engineering development of MR fluids is presented, followed by some of the common methods for modelling their non-Newtonian behaviour. The common modes of the MR fluids are discussed, along with the application of the fluid in valve mode for ground vehicles' dampers (or shock absorbers). The applications span across nearly all road vehicles, including automobiles, trains, semi-trucks, motorcycles, and even bicycles. For each type of vehicle, the results of some of the past studies is presented briefly, with reference to the originating study. It is discussed that Past experimental and modelling studies have indicated that MR suspensions provide clear advantages for ground vehicles that far surpasses the performance of passive suspension. For rail vehicles, the primary advantage is in terms of increasing the speed at which the onset of hunting occurs, whereas for road vehicles - mainly automobiles - the performance improvements are in terms of a better balance between vehicle ride, handling, and stability. To further elaborate on this point, a single-suspension model is used to develop an index-based approach for studying the compromise that is offered by vehicle suspensions, using the H2 optimisation approach. Evaluating three indices based on the sprung-mass acceleration, suspension rattlespace, and tyre deflection, it is clearly demonstrated that MR suspensions significantly improve road vehicle's ride comfort, stability, and handling in comparison with passive suspensions. For rail vehicles, the simulation results indicate that using MR suspensions with an on-off switching control can increase the speed at which the on-set of hunting occurs by as much as 50% to more than 300%.

Evaluation of handle design characteristics in a maximum screwdriving torque task.

PubMed

Kong, Y-K; Lowe, B D; Lee, S-J; Krieg, E F

2007-09-01

The purpose of this study was to evaluate the effects of screwdriver handle shape, surface material and workpiece orientation on torque performance, finger force distribution and muscle activity in a maximum screwdriving torque task. Twelve male subjects performed maximum screw-tightening exertions using screwdriver handles with three longitudinal shapes (circular, hexagonal and triangular), four lateral shapes (cylindrical, double frustum, cone and reversed double frustum) and two surfaces (rubber and plastic). The average finger force contributions to the total hand force were 28.1%, 39.3%, 26.5% and 6.2%, in order from index to little fingers; the average phalangeal segment force contributions were 47.3%, 14.0%, 20.5% and 18.1% for distal, middle, proximal and metacarpal phalanges, respectively. The plastic surface handles were associated with 15% less torque output (4.86 Nm) than the rubber coated handles (5.73 Nm). In general, the vertical workpiece orientation was associated with higher torque output (5.9 Nm) than the horizontal orientation (4.69 Nm). Analysis of handle shapes indicates that screwdrivers designed with a circular or hexagonal cross-sectional shape result in greater torque outputs (5.49 Nm, 5.57 Nm), with less total finger force (95 N, 105 N). In terms of lateral shape, reversed double frustum handles were associated with less torque output (5.23 Nm) than the double frustum (5.44 Nm) and cone (5.37 Nm) handles. Screwdriver handles designed with combinations of circular or hexagonal cross-sectional shapes with double frustum and cone lateral shapes were optimal in this study.

Intelligent herbicide application system for reduced herbicide vegetation control : phase II-commercialization

DOT National Transportation Integrated Search

2008-12-01

This report describes the development of a commercial prototype intelligent herbicide application system : (IHAS). The improved design incorporates a parallel add-on type fluid handling system to allow existing : variable-rate herbicide injecti...

Traffic Flow Density Distribution Based on FEM

NASA Astrophysics Data System (ADS)

Ma, Jing; Cui, Jianming

In analysis of normal traffic flow, it usually uses the static or dynamic model to numerical analyze based on fluid mechanics. However, in such handling process, the problem of massive modeling and data handling exist, and the accuracy is not high. Finite Element Method (FEM) is a production which is developed from the combination of a modern mathematics, mathematics and computer technology, and it has been widely applied in various domain such as engineering. Based on existing theory of traffic flow, ITS and the development of FEM, a simulation theory of the FEM that solves the problems existing in traffic flow is put forward. Based on this theory, using the existing Finite Element Analysis (FEA) software, the traffic flow is simulated analyzed with fluid mechanics and the dynamics. Massive data processing problem of manually modeling and numerical analysis is solved, and the authenticity of simulation is enhanced.

A scintillator purification plant and fluid handling system for SNO+

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ford, Richard J., E-mail: ford@snolab.ca

A large capacity purification plant and fluid handling system has been constructed for the SNO+ neutrino and double-beta decay experiment, located 6800 feet underground at SNOLAB, Canada. SNO+ is a refurbishment of the SNO detector to fill the acrylic vessel with liquid scintillator based on Linear Alkylbenzene (LAB) and 2 g/L PPO, and also has a phase to load natural tellurium into the scintillator for a double-beta decay experiment with {sup 130}Te. The plant includes processes multi-stage dual-stream distillation, column water extraction, steam stripping, and functionalized silica gel adsorption columns. The plant also includes systems for preparing the scintillator with PPOmore » and metal-loading the scintillator for double-beta decay exposure. We review the basis of design, the purification principles, specifications for the plant, and the construction and installations. The construction and commissioning status is updated.« less

Handling of hazardous drugs - Effect of an innovative teaching session for nursing students.

PubMed

Zimmer, Janine; Hartl, Stefanie; Standfuß, Katrin; Möhn, Till; Bertsche, Astrid; Frontini, Roberto; Neininger, Martina P; Bertsche, Thilo

2017-02-01

Imparting knowledge and practical skills in hazardous drug handling in nursing students' education is essential to prevent hazardous exposure and to preserve nurses' health. This study aimed at comparing routine nursing education with an additional innovative teaching session. A prospective controlled study in nursing students was conducted in two study periods: (i) a status-quo period (routine education on handling hazardous drugs) followed by (ii) an intervention period (additional innovative teaching session on handling hazardous drugs). Nursing students at a vocational school were invited to participate voluntarily. In both study periods (i) and (ii), the following factors were analysed: (a) knowledge of hazardous drug handling by questionnaire, (b) practical skills in hazardous drug handling (e.g. cleaning) by a simulated handling scenario, (c) contamination with drug residuals on the work surface by fluorescent imaging. Fifty-three nursing students were enrolled. (a) Median knowledge improved from status-quo (39% right answers) to intervention (65%, p<0.001), (b) practical skills improved from status-quo (53% of all participants cleaned the work surface) to intervention (92%, p<0.001). (c) Median number of particles/m 2 decreased from status-quo to intervention (932/97, p<0.001). Compared with routine education, knowledge and practical skills in hazardous drug handling were significantly improved after an innovative teaching session. Additionally, the amount of residuals on the work surface decreased. This indicates a lower risk for hazardous drug exposure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Presentation of flight control design and handling quality commonality by separate surface stability augmentation for the family of commuter airplanes

NASA Technical Reports Server (NTRS)

Hensley, Douglas; Creighton, Thomas; Haddad, Raphael; Hendrich, Louis; Morgan, Louise; Russell, Mark; Swift, Gerald

1987-01-01

The methodology and results for a flight control design and implementation for common handling qualities by Separate Surface Stability Augmentation (SSSA) for the family of commuter airplanes are contained. The open and closed loop dynamics and the design results of augmenting for common handling qualities are presented. The physical and technology requirements are presented for implementing the SSSA system. The conclusion of this report and recommendations for changes or improvement are discussed.

An interface capturing scheme for modeling atomization in compressible flows

NASA Astrophysics Data System (ADS)

Garrick, Daniel P.; Hagen, Wyatt A.; Regele, Jonathan D.

2017-09-01

The study of atomization in supersonic flow is critical to ensuring reliable ignition of scramjet combustors under startup conditions. Numerical methods incorporating surface tension effects have largely focused on the incompressible regime as most atomization applications occur at low Mach numbers. Simulating surface tension effects in compressible flow requires robust numerical methods that can handle discontinuities caused by both shocks and material interfaces with high density ratios. In this work, a shock and interface capturing scheme is developed that uses the Harten-Lax-van Leer-Contact (HLLC) Riemann solver while a Tangent of Hyperbola for INterface Capturing (THINC) interface reconstruction scheme retains the fluid immiscibility condition in the volume fraction and phasic densities in the context of the five equation model. The approach includes the effects of compressibility, surface tension, and molecular viscosity. One and two-dimensional benchmark problems demonstrate the desirable interface sharpening and conservation properties of the approach. Simulations of secondary atomization of a cylindrical water column after its interaction with a shockwave show good qualitative agreement with experimentally observed behavior. Three-dimensional examples of primary atomization of a liquid jet in a Mach 2 crossflow demonstrate the robustness of the method.

Dynamic, Hot Surface Ignition of Aircraft Fuels and Hydraulic Fluids

DTIC Science & Technology

1980-10-01

fuels on a heated stainless steel surface. Higher local surface air speeds necessitated higher surface temperatures for ignition of an applied fluid._-7...Aircraft Fuels ( stainless steel surface) 8. Air Speed and Surface Material Effects on Hot Surface 21 Ignition Temperature of Aircraft Fuels (Titanium...Material Effects on Hot Surface 26 Ignition Temperature of Aircraft Hydraulic Fluids ( Stainless steel surface) 11. Air Speed and Surface Material

[Analysis on accuracy and influencing factors of oral fluid-based rapid HIV self-testing among men who have sex with men].

PubMed

Li, Youfang; Wang, Yumiao; Zhang, Renzhong; Wang, Jue; Li, Zhiqing; Wang, Ling; Pan, Songfeng; Yang, Yanling; Ma, Yanling; Jia, Manhong

2016-01-01

To understood the accuracy of oral fluid-based rapid HIV self-testing among men who have sex with men (MSM) and related factors. Survey was conducted among MSM selected through non-probability sampling to evaluate the quality of their rapid HIV self-testing, and related information was analyzed. The most MSM were aged 21-30 years (57.0%). Among them, 45.7% had educational level of college or above, 78.5% were unmarried, 59.3% were casual laborers. The overall accuracy rate of oral fluid based self-testing was 95.0%, the handling of"inserting test paper into tube as indicated by arrow on it"had the highest accuracy rate (98.0%), and the handling of"gently upsetting tube for 3 times"had lowest accuracy rate (65.0%); Chi-square analysis showed that educational level, no touch with middle part of test paper, whether reading the instruction carefully, whether understanding the instruction and inserting test paper into tube as indicated by the arrow on it were associated with the accuracy of oral fluid-based rapid HIV self-testing, (P<0.05). Multivariate logistic regression analysis indicated that educational level, no touch with middle part of test paper and understanding instructions were associated with the accuracy of oral fluid-based rapid HIV self-testing. The accuracy of oral fluid-based rapid HIV self-testing was high among MSM, the accuracy varied with the educational level of the MSM. Touch with the middle part of test paper or not and understanding the instructions or not might influence the accuracy of the self-testing.

Generating Inviscid and Viscous Fluid Flow Simulations over a Surface Using a Quasi-simultaneous Technique

NASA Technical Reports Server (NTRS)

Sturdza, Peter (Inventor); Martins-Rivas, Herve (Inventor); Suzuki, Yoshifumi (Inventor)

2014-01-01

A fluid-flow simulation over a computer-generated surface is generated using a quasi-simultaneous technique. The simulation includes a fluid-flow mesh of inviscid and boundary-layer fluid cells. An initial fluid property for an inviscid fluid cell is determined using an inviscid fluid simulation that does not simulate fluid viscous effects. An initial boundary-layer fluid property a boundary-layer fluid cell is determined using the initial fluid property and a viscous fluid simulation that simulates fluid viscous effects. An updated boundary-layer fluid property is determined for the boundary-layer fluid cell using the initial fluid property, initial boundary-layer fluid property, and an interaction law. The interaction law approximates the inviscid fluid simulation using a matrix of aerodynamic influence coefficients computed using a two-dimensional surface panel technique and a fluid-property vector. An updated fluid property is determined for the inviscid fluid cell using the updated boundary-layer fluid property.

Preliminary Design Optimization For A Supersonic Turbine For Rocket Propulsion

NASA Technical Reports Server (NTRS)

Papila, Nilay; Shyy, Wei; Griffin, Lisa; Huber, Frank; Tran, Ken; McConnaughey, Helen (Technical Monitor)

2000-01-01

In this study, we present a method for optimizing, at the preliminary design level, a supersonic turbine for rocket propulsion system application. Single-, two- and three-stage turbines are considered with the number of design variables increasing from 6 to 11 then to 15, in accordance with the number of stages. Due to its global nature and flexibility in handling different types of information, the response surface methodology (RSM) is applied in the present study. A major goal of the present Optimization effort is to balance the desire of maximizing aerodynamic performance and minimizing weight. To ascertain required predictive capability of the RSM, a two-level domain refinement approach has been adopted. The accuracy of the predicted optimal design points based on this strategy is shown to he satisfactory. Our investigation indicates that the efficiency rises quickly from single stage to 2 stages but that the increase is much less pronounced with 3 stages. A 1-stage turbine performs poorly under the engine balance boundary condition. A portion of fluid kinetic energy is lost at the turbine discharge of the 1-stage design due to high stage pressure ratio and high-energy content, mostly hydrogen, of the working fluid. Regarding the optimization technique, issues related to the design of experiments (DOE) has also been investigated. It is demonstrated that the criteria for selecting the data base exhibit significant impact on the efficiency and effectiveness of the construction of the response surface.

sFIDA automation yields sub-femtomolar limit of detection for Aβ aggregates in body fluids.

PubMed

Herrmann, Yvonne; Kulawik, Andreas; Kühbach, Katja; Hülsemann, Maren; Peters, Luriano; Bujnicki, Tuyen; Kravchenko, Kateryna; Linnartz, Christina; Willbold, Johannes; Zafiu, Christian; Bannach, Oliver; Willbold, Dieter

2017-03-01

Alzheimer's disease (AD) is a neurodegenerative disorder with yet non-existent therapeutic and limited diagnostic options. Reliable biomarker-based AD diagnostics are of utmost importance for the development and application of therapeutic substances. We have previously introduced a platform technology designated 'sFIDA' for the quantitation of amyloid β peptide (Aβ) aggregates as AD biomarker. In this study we implemented the sFIDA assay on an automated platform to enhance robustness and performance of the assay. In sFIDA (surface-based fluorescence intensity distribution analysis) Aβ species are immobilized by a capture antibody to a glass surface. Aβ aggregates are then multiply loaded with fluorescent antibodies and quantitated by high resolution fluorescence microscopy. As a model system for Aβ aggregates, we used Aβ-conjugated silica nanoparticles (Aβ-SiNaPs) diluted in PBS buffer and cerebrospinal fluid, respectively. Automation of the assay was realized on a liquid handling system in combination with a microplate washer. The automation of the sFIDA assay results in improved intra-assay precision, linearity and sensitivity in comparison to the manual application, and achieved a limit of detection in the sub-femtomolar range. Automation improves the precision and sensitivity of the sFIDA assay, which is a prerequisite for high-throughput measurements and future application of the technology in routine AD diagnostics. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Secondary electroosmotic flow in microchannels with nonuniform and asymmetric Zeta potential

NASA Astrophysics Data System (ADS)

Zhang, Jinbai; He, Guowei; Liu, Feng

2004-11-01

Microfluidics has a broad range of applications in biotechnology, such as sample injection, drug delivering, solution mixing, and separations. All of these techniques require handling fluids in the low Reynolds number (Re) regime. Electroosmotic flow (EOF) or electroosmocitcs is the bulk movement of liquid relative to a stationary surface due to an externally applied electronic field. It is an alternative to pressure-driven flows with convenient implementation The driving force for EOF is dependent on the zeta potential. Previous reseraches focus on the nonuniform Zeta potential. In the present work, we consider nonuniform and asymmetric Zeta potential. The effects of asymmetric Zeta potential on the EOF are investigated analytically and simulated numerically. It is demonstrated that the nonuniform and asymmetric Zeta potential can generate more flow patterns for microfluidic control compared to symmetric Zeta potential.

Direct and Inverse Scattering Problem Associated with the Elliptic Sinh-Gordon Equation

DTIC Science & Technology

1989-11-14

the simple matter of an ambiguity in the quantization of two dimensional Hamiltonian systems, a problem that is easily handled. Our notation is as...siderable evidence has been found in support of a dark- matter fluctuation equations on a background satisfying an expansion hypothesis: suppose the... matter that does porate the case in which one of the fluids is a photon fluid. Of not interact directly with ordinary matter and in particular with

Easy-To-Use Connector-Assembly Tool

NASA Technical Reports Server (NTRS)

Redmon, John W., Jr.; Jankowski, Fred

1988-01-01

Tool compensates for user's loss of dexterity under awkward conditions. Has jaws that swivel over 180 degree so angle adjusts with respect to handles. Oriented and held in position most comfortable and effective for user in given situation. Jaws lined with rubber pads so they conform to irregularly shaped parts and grips firmly but gently. Once tool engages part, it locks on it so user can release handles without losing part. Ratchet mechanism in tool allows user to work handles back and forth in confined space to connect or disconnect part. Quickly positioned, locked, and released. Gives user feel of its grip on part. Frees grasping muscles from work during part of task, giving user greater freedom to move hand. Operates with only one hand, leaving user's other hand free to manipulate wiring or other parts. Also adapts to handling and positioning extremely-hot or extremely-cold fluid lines, contaminated objects, abrasive or sharp objects, fragile items, and soft objects.

Coupled multiphase flow and geomechanics analysis of the 2011 Lorca earthquake

NASA Astrophysics Data System (ADS)

Jha, B.; Hager, B. H.; Juanes, R.; Bechor, N.

2013-12-01

We present a new approach for modeling coupled multiphase flow and geomechanics of faulted reservoirs. We couple a flow simulator with a mechanics simulator using the unconditionally stable fixed-stress sequential solution scheme [Kim et al, 2011]. We model faults as surfaces of discontinuity using interface elements [Aagaard et al, 2008]. This allows us to model stick-slip behavior on the fault surface for dynamically evolving fault strength. We employ a rigorous formulation of nonlinear multiphase geomechanics [Coussy, 1995], which is based on the increment in mass of fluid phases instead of the traditional, and less accurate, scheme based on the change in porosity. Our nonlinear formulation is capable of handling strong capillarity and large changes in saturation in the reservoir. To account for the effect of surface stresses along fluid-fluid interfaces, we use the equivalent pore pressure in the definition of the multiphase effective stress [Coussy et al, 1998; Kim et al, 2013]. We use our simulation tool to study the 2011 Lorca earthquake [Gonzalez et al, 2012], which has received much attention because of its potential anthropogenic triggering (long-term groundwater withdrawal leading to slip along the regional Alhama de Murcia fault). Our coupled fluid flow and geomechanics approach to model fault slip allowed us to take a fresh look at this seismic event, which to date has only been analyzed using simple elastic dislocation models and point source solutions. Using a three-dimensional model of the Lorca region, we simulate the groundwater withdrawal and subsequent unloading of the basin over the period of interest (1960-2010). We find that groundwater withdrawal leads to unloading of the crust and changes in the stress across the impermeable fault plane. Our analysis suggests that the combination of these two factors played a critical role in inducing the fault slip that ultimately led to the Lorca earthquake. Aagaard, B. T., M. G. Knepley, and C. A. Williams (2013), Journal of Geophysical Research, Solid Earth, 118, 3059-3079 Coussy, O. (1995), Mechanics of Porous Continua, John Wiley and Sons, England. Coussy, O., R. Eymard, and T. Lassabatere (1998), J. Eng. Mech., 124(6), 658-557. Kim, J., H. A. Tchelepi, and R. Juanes (2011), Comput. Methods Appl. Mech. Eng., 200, 1591-1606. Gonzalez, P. J., K. F. Tiampo, M. Palano, F. Cannavo, and J. Fernandez (2012), Nature Geoscience.

Fluidics cube for biosensor miniaturization

NASA Technical Reports Server (NTRS)

Dodson, J. M.; Feldstein, M. J.; Leatzow, D. M.; Flack, L. K.; Golden, J. P.; Ligler, F. S.

2001-01-01

To create a small, portable, fully automated biosensor, a compact means of fluid handling is required. We designed, manufactured, and tested a "fluidics cube" for such a purpose. This cube, made of thermoplastic, contains reservoirs and channels for liquid samples and reagents and operates without the use of any internal valves or meters; it is a passive fluid circuit that relies on pressure relief vents to control fluid movement. We demonstrate the ability of pressure relief vents to control fluid movement and show how to simply manufacture or modify the cube. Combined with the planar array biosensor developed at the Naval Research Laboratory, it brings us one step closer to realizing our goal of a handheld biosensor capable of analyzing multiple samples for multiple analytes.

Impact on a Compressible Fluid

NASA Technical Reports Server (NTRS)

Egorov, L. T.

1958-01-01

Upon impact of a solid body on the plane surface of a fluid, there occurs on the vetted surface of the body an abrupt pressure rise which propagates into both media with the speed of sound. Below, we assume the case where the speed of propagation of sound in the body which falls on the surface of the fluid may be regarded as infinitely large in comparison with the speed of propagation of sound in the fluid; that is, we shall assume that the falling body is absolutely rigid. IN this case, the entire relative speed of the motion which takes place at the beginning of the impact is absorbed by the fluid. The hydrodynamic pressures arising thereby are propagated from the contact surface within the fluid with the speed of sound in the form of compression and expansion waves and are gradually damped. After this, they are dispersed like impact pressures, reach ever larger regions of the fluid remote fran the body and became equal to zero; in the fluid there remain hydrodynamic pressures corresponding to the motion of the body after the impact. Neglecting the forces of viscosity and taking into account, furthermore, that the motion of the fluid begins from a state of rest, according to Thomson's theorem, we may consider the motion of an ideal compressible fluid in the process of impact to be potential. We examine the case of impact upon the surface of a ccmpressible fluid of a flat plate of infinite extent or of a body, the immersed part of the surface of which may be called approximately flat. In this report we discuss the first phase of the impact pressure on the surface of a fluid, prior to the appearance of a cavity, since at this stage the hydrodynamic pressures reach their maximum values. Observations, after the fall of the bodies on the surface of the fluid, show that the free surface of the fluid at this stage is almost completely at rest if one does not take into account the small rise in the neighborhood of the boundaries of the impact surface.

Hydraulic Fracturing for Oil and Gas: Impacts from the ...

EPA Pesticide Factsheets

This final report provides a review and synthesis of available scientific information concerning the relationship between hydraulic fracturing activities and drinking water resources in the United States. The report is organized around activities in the hydraulic fracturing water cycle and their potential to impact drinking water resources.  The stages include: (1) acquiring water to be used for hydraulic fracturing (Water Acquisition), (2) mixing the water with chemical additives to prepare hydraulic fracturing fluids (Chemical Mixing), (3) injecting the hydraulic fracturing fluids into the production well to create fractures in the targeted production zone (Well Injection), (4) collecting the wastewater that returns through the well after injection (Produced Water Handling), and (5) managing the wastewater via disposal or reuse methods (Wastewater Disposal and Reuse). EPA found scientific evidence that hydraulic fracturing activities can impact drinking water resources under some circumstances. The report identifies certain conditions under which impacts from hydraulic fracturing activities can be more frequent or severe: Water withdrawals for hydraulic fracturing in times or areas of low water availability, particularly in areas with limited or declining groundwater resources; Spills during the handling of hydraulic fracturing fluids and chemicals or produced water that result in large volumes or high concentrations of chem

Multiscale Universal Interface: A concurrent framework for coupling heterogeneous solvers

NASA Astrophysics Data System (ADS)

Tang, Yu-Hang; Kudo, Shuhei; Bian, Xin; Li, Zhen; Karniadakis, George Em

2015-09-01

Concurrently coupled numerical simulations using heterogeneous solvers are powerful tools for modeling multiscale phenomena. However, major modifications to existing codes are often required to enable such simulations, posing significant difficulties in practice. In this paper we present a C++ library, i.e. the Multiscale Universal Interface (MUI), which is capable of facilitating the coupling effort for a wide range of multiscale simulations. The library adopts a header-only form with minimal external dependency and hence can be easily dropped into existing codes. A data sampler concept is introduced, combined with a hybrid dynamic/static typing mechanism, to create an easily customizable framework for solver-independent data interpretation. The library integrates MPI MPMD support and an asynchronous communication protocol to handle inter-solver information exchange irrespective of the solvers' own MPI awareness. Template metaprogramming is heavily employed to simultaneously improve runtime performance and code flexibility. We validated the library by solving three different multiscale problems, which also serve to demonstrate the flexibility of the framework in handling heterogeneous models and solvers. In the first example, a Couette flow was simulated using two concurrently coupled Smoothed Particle Hydrodynamics (SPH) simulations of different spatial resolutions. In the second example, we coupled the deterministic SPH method with the stochastic Dissipative Particle Dynamics (DPD) method to study the effect of surface grafting on the hydrodynamics properties on the surface. In the third example, we consider conjugate heat transfer between a solid domain and a fluid domain by coupling the particle-based energy-conserving DPD (eDPD) method with the Finite Element Method (FEM).

Multiscale Universal Interface: A concurrent framework for coupling heterogeneous solvers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, Yu-Hang, E-mail: yuhang_tang@brown.edu; Kudo, Shuhei, E-mail: shuhei-kudo@outlook.jp; Bian, Xin, E-mail: xin_bian@brown.edu

2015-09-15

Graphical abstract: - Abstract: Concurrently coupled numerical simulations using heterogeneous solvers are powerful tools for modeling multiscale phenomena. However, major modifications to existing codes are often required to enable such simulations, posing significant difficulties in practice. In this paper we present a C++ library, i.e. the Multiscale Universal Interface (MUI), which is capable of facilitating the coupling effort for a wide range of multiscale simulations. The library adopts a header-only form with minimal external dependency and hence can be easily dropped into existing codes. A data sampler concept is introduced, combined with a hybrid dynamic/static typing mechanism, to create anmore » easily customizable framework for solver-independent data interpretation. The library integrates MPI MPMD support and an asynchronous communication protocol to handle inter-solver information exchange irrespective of the solvers' own MPI awareness. Template metaprogramming is heavily employed to simultaneously improve runtime performance and code flexibility. We validated the library by solving three different multiscale problems, which also serve to demonstrate the flexibility of the framework in handling heterogeneous models and solvers. In the first example, a Couette flow was simulated using two concurrently coupled Smoothed Particle Hydrodynamics (SPH) simulations of different spatial resolutions. In the second example, we coupled the deterministic SPH method with the stochastic Dissipative Particle Dynamics (DPD) method to study the effect of surface grafting on the hydrodynamics properties on the surface. In the third example, we consider conjugate heat transfer between a solid domain and a fluid domain by coupling the particle-based energy-conserving DPD (eDPD) method with the Finite Element Method (FEM)« less

A fast numerical method for ideal fluid flow in domains with multiple stirrers

NASA Astrophysics Data System (ADS)

Nasser, Mohamed M. S.; Green, Christopher C.

2018-03-01

A collection of arbitrarily-shaped solid objects, each moving at a constant speed, can be used to mix or stir ideal fluid, and can give rise to interesting flow patterns. Assuming these systems of fluid stirrers are two-dimensional, the mathematical problem of resolving the flow field—given a particular distribution of any finite number of stirrers of specified shape and speed—can be formulated as a Riemann-Hilbert (R-H) problem. We show that this R-H problem can be solved numerically using a fast and accurate algorithm for any finite number of stirrers based around a boundary integral equation with the generalized Neumann kernel. Various systems of fluid stirrers are considered, and our numerical scheme is shown to handle highly multiply connected domains (i.e. systems of many fluid stirrers) with minimal computational expense.

Observation of a new surface mode on a fluid-saturated permeable solid

NASA Astrophysics Data System (ADS)

Nagy, Peter B.

1992-06-01

Almost ten years ago, S. Feng and D. L. Johnson predicted the presence of a new surface mode on a fluid/fluid-saturated porous solid interface with closed surface pores [J. Acoust. Soc. Am. 74, 906 (1983)]. We found that, due to surface tension, practically closed-pore boundary conditions can prevail at an interface between a nonwetting fluid (e.g., air) and a porous solid saturated with a wetting fluid (e.g., water or alcohol). Surface wave velocity and attenuation measurements were made on alcohol-saturated porous sintered glass at 100 kHz. The experimental results show clear evidence of the new ``slow'' surface mode predicted by Feng and Johnson.

Measurements of acoustic surface waves on fluid-filled porous rocks

NASA Astrophysics Data System (ADS)

Adler, Laszlo; Nagy, Peter B.

1994-09-01

Novel experimental techniques to measure ultrasonic velocity and attenuation of surface waves on fluid-filled porous natural rocks are presented. Our experimental results are consistent with the theoretical predictions of Feng and Johnson (1983). Depending on the interface conditions, i.e., whether the surface pores are open or closed, pseudo-Rayleigh, pseudo-Stoneley, and/or Stoneley surface waves may exist on fluid-saturated rocks with closed 'slow' surface wave (true Stoneley mode) on fluid-filled porous rocks with closed surface pores. The velocity and attenuation of the 'slow' surface mode may be used to assess the dynamic permeabilty of porous formations.

Fluid-structure interaction simulations of deformable structures with non-linear thin shell elements

NASA Astrophysics Data System (ADS)

Asgharzadeh, Hafez; Hedayat, Mohammadali; Borazjani, Iman; Scientific Computing; Biofluids Laboratory Team

2017-11-01

Large deformation of structures in a fluid is simulated using a strongly coupled partitioned fluid-structure interaction (FSI) approach which is stabilized with under-relaxation and the Aitken acceleration technique. The fluid is simulated using a recently developed implicit Newton-Krylov method with a novel analytical Jacobian. Structures are simulated using a triangular thin-shell finite element formulation, which considers only translational degrees of freedom. The thin-shell method is developed on the top of a previously implemented membrane finite element formulation. A sharp interface immersed boundary method is used to handle structures in the fluid domain. The developed FSI framework is validated against two three-dimensional experiments: (1) a flexible aquatic vegetation in the fluid and (2) a heaving flexible panel in fluid. Furthermore, the developed FSI framework is used to simulate tissue heart valves, which involve large deformations and non-linear material properties. This work was supported by American Heart Association (AHA) Grant 13SDG17220022 and the Center of Computational Research (CCR) of University at Buffalo.

30 CFR 75.1709 - Accumulations of methane and coal dust on surface coal-handling facilities.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Accumulations of methane and coal dust on surface coal-handling facilities. 75.1709 Section 75.1709 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

30 CFR 75.1709 - Accumulations of methane and coal dust on surface coal-handling facilities.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Accumulations of methane and coal dust on surface coal-handling facilities. 75.1709 Section 75.1709 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

30 CFR 75.1709 - Accumulations of methane and coal dust on surface coal-handling facilities.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Accumulations of methane and coal dust on surface coal-handling facilities. 75.1709 Section 75.1709 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

30 CFR 75.1709 - Accumulations of methane and coal dust on surface coal-handling facilities.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Accumulations of methane and coal dust on surface coal-handling facilities. 75.1709 Section 75.1709 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...

Gas turbine engine exhaust diffuser including circumferential vane

DOEpatents

Orosa, John A.; Matys, Pawel

2015-05-19

A flow passage defined between an inner and an outer boundary for guiding a fluid flow in an axial direction. A flow control vane is supported at a radial location between the inner and outer boundaries. A fluid discharge opening is provided for discharging a flow of the compressed fluid from a trailing edge of the vane, and a fluid control surface is provided adjacent to the fluid discharge opening and extends in the axial direction at the trailing edge of the vane. The fluid control surface has a curved trailing edge forming a Coanda surface. The fluid discharge opening is selectively provided with a compressed fluid to produce a Coanda effect along the control surface. The Coanda effect has a component in the radial direction effecting a turning of the fluid flow in the flow path radially inward or outward toward one of the inner and outer boundaries.

Thermal energy management process experiment

NASA Technical Reports Server (NTRS)

Ollendorf, S.

1984-01-01

The thermal energy management processes experiment (TEMP) will demonstrate that through the use of two-phase flow technology, thermal systems can be significantly enhanced by increasing heat transport capabilities at reduced power consumption while operating within narrow temperature limits. It has been noted that such phenomena as excess fluid puddling, priming, stratification, and surface tension effects all tend to mask the performance of two-phase flow systems in a 1-g field. The flight experiment approach would be to attack the experiment to an appropriate mounting surface with a 15 to 20 meter effective length and provide a heat input and output station in the form of heaters and a radiator. Using environmental data, the size, location, and orientation of the experiment can be optimized. The approach would be to provide a self-contained panel and mount it to the STEP through a frame. A small electronics package would be developed to interface with the STEP avionics for command and data handling. During the flight, heaters on the evaporator will be exercised to determine performance. Flight data will be evaluated against the ground tests to determine any anomalous behavior.

Systems and methods for thermal imaging technique for measuring mixing of fluids

DOEpatents

Booten, Charles; Tomerlin, Jeff; Winkler, Jon

2016-06-14

Systems and methods for thermal imaging for measuring mixing of fluids are provided. In one embodiment, a method for measuring mixing of gaseous fluids using thermal imaging comprises: positioning a thermal test medium parallel to a direction gaseous fluid flow from an outlet vent of a momentum source, wherein when the source is operating, the fluid flows across a surface of the medium; obtaining an ambient temperature value from a baseline thermal image of the surface; obtaining at least one operational thermal image of the surface when the fluid is flowing from the outlet vent across the surface, wherein the fluid has a temperature different than the ambient temperature; and calculating at least one temperature-difference fraction associated with at least a first position on the surface based on a difference between temperature measurements obtained from the at least one operational thermal image and the ambient temperature value.

High precision high flow range control valve

DOEpatents

McCray, J.A.

1999-07-13

A fluid control valve is described having a valve housing having first and second valve housing openings for the ingress and egress of fluid through the control valve. Disposed within a void formed by the control valve is a sleeve having at least one sleeve opening to permit the flow of fluid therethrough. A flow restricter travels within the sleeve to progressively block off the sleeve opening and thereby control flow. A fluid passageway is formed between the first valve housing opening and the outer surface of the sleeve. A second fluid passageway is formed between the inside of the sleeve and the second valve housing opening. Neither fluid passageway contains more than one 90 [degree] turn. In the preferred embodiment only one of the two fluid passageways contains a 90[degree] turn. In another embodiment, the control valve housing is bifurcated by a control surface having control surface opening disposed therethrough. A flow restricter is in slidable contact with the control surface to restrict flow of fluid through the control surface openings. 12 figs.

High precision high flow range control valve

DOEpatents

McCray, John A.

1999-01-01

A fluid control valve is described having a valve housing having first and second valve housing openings for the ingress and egress of fluid through the control valve. Disposed within a void formed by the control valve is a sleeve having at least one sleeve opening to permit the flow of fluid therethrough. A flow restricter travels within the sleeve to progressively block off the sleeve opening and thereby control flow. A fluid passageway is formed between the first valve housing opening and the outer surface of the sleeve. A second fluid passageway is formed between the inside of the sleeve and the second valve housing opening. Neither fluid passageway contains more than one 90.degree. turn. In the preferred embodiment only one of the two fluid passageways contains a 90.degree. turn. In another embodiment, the control valve housing is bifurcated by a control surface having control surface opening disposed therethrough. A flow restricter is in slidable contact with the control surface to restrict flow of fluid through the control surface openings.

Surface tension in human pathophysiology and its application as a medical diagnostic tool

PubMed Central

Fathi-Azarbayjani, Anahita; Jouyban, Abolghasem

2015-01-01

Introduction: Pathological features of disease appear to be quite different. Despite this diversity, the common feature of various disorders underlies physicochemical and biochemical factors such as surface tension. Human biological fluids comprise various proteins and phospholipids which are capable of adsorption at fluid interfaces and play a vital role in the physiological function of human organs. Surface tension of body fluids correlates directly to the development of pathological states. Methods: In this review, the variety of human diseases mediated by the surface tension changes of biological phenomena and the failure of biological fluids to remain in their native state are discussed. Results: Dynamic surface tension measurements of human biological fluids depend on various parameters such as sex, age and changes during pregnancy or certain disease. It is expected that studies of surface tension behavior of human biological fluids will provide additional information and might become useful in medical practice. Theoretical background on surface tension measurement and surface tension values of reference fluids obtained from healthy and sick patients are depicted. Conclusion: It is well accepted that no single biomarker will be effective in clinical diagnosis. The surface tension measurement combined with routine lab tests may be a novel non-invasive method which can not only facilitate the discovery of diagnostic models for various diseases and its severity, but also be a useful tool for monitoring treatment efficacy. We therefore expect that studies of surface tension behavior of human biological fluids will provide additional useful information in medical practice. PMID:25901295

Robotics

NASA Technical Reports Server (NTRS)

Ambrose, Robert O.

2007-01-01

Lunar robotic functions include: 1. Transport of crew and payloads on the surface of the moon; 2. Offloading payloads from a lunar lander; 3. Handling the deployment of surface systems; with 4. Human commanding of these functions from inside a lunar vehicle, habitat, or extravehicular (space walk), with Earth-based supervision. The systems that will perform these functions may not look like robots from science fiction. In fact, robotic functions may be automated trucks, cranes and winches. Use of this equipment prior to the crew s arrival or in the potentially long periods without crews on the surface, will require that these systems be computer controlled machines. The public release of NASA's Exploration plans at the 2nd Space Exploration Conference (Houston, December 2006) included a lunar outpost with as many as four unique mobility chassis designs. The sequence of lander offloading tasks involved as many as ten payloads, each with a unique set of geometry, mass and interface requirements. This plan was refined during a second phase study concluded in August 2007. Among the many improvements to the exploration plan were a reduction in the number of unique mobility chassis designs and a reduction in unique payload specifications. As the lunar surface system payloads have matured, so have the mobility and offloading functional requirements. While the architecture work continues, the community can expect to see functional requirements in the areas of surface mobility, surface handling, and human-systems interaction as follows: Surface Mobility 1. Transport crew on the lunar surface, accelerating construction tasks, expanding the crew s sphere of influence for scientific exploration, and providing a rapid return to an ascent module in an emergency. The crew transport can be with an un-pressurized rover, a small pressurized rover, or a larger mobile habitat. 2. Transport Extra-Vehicular Activity (EVA) equipment and construction payloads. 3. Transport habitats and power modules over long distances, pre-positioning them for the arrival of crew on a subsequent lander. Surface Handling 1. Offload surface system payloads from the lander, breaking launch restraints and power/data connections. Payloads may be offloaded to a wheeled vehicle for transport. 2. Deploy payloads from a wheeled vehicle at a field site, placing the payloads in their final use site on the ground or mating them with existing surface systems. 3. Support regolith collection, site preparation, berm construction, or other civil engineering tasks using tools and implements attached to rovers. Human-Systems Interaction 1. Provide a safe command and control interface for suited EVA to ride on and drive the vehicles, making sure that the systems are also safe for working near dismounted crew. 2. Provide an effective control system for IV crew to tele-operate vehicles, cranes and other equipment from inside the surface habitats with evolving independence from Earth. .. Provide a supervisory system that allows machines to be commanded from the ground, working across the Earth-Lunar time delays on the order of 5-10 seconds (round trip) to support operations when crew are not resident on the surface. Technology Development Needs 1. Surface vehicles that can dock, align and mate with outpost equipment such as landers, habitats and fluid/power interfaces. 2. Long life motors, drive trains, seals, motor electronics, sensors, processors, cable harnesses, and dash board displays. 3. Active suspension control, localization, high speed obstacle avoidance, and safety systems for operating near dismounted crew. 4. High specific energy and specific power batteries that are safe, rechargeable, and long lived.

Swirling structure for mixing two concentric fluid flows at nozzle outlet

DOEpatents

Mensink, Daniel L.

1993-01-01

A nozzle device for causing two fluids to mix together. In particular, a spray nozzle comprise two hollow, concentric housings, an inner housing and an outer housing. The inner housing has a channel formed therethrough for a first fluid. Its outer surface cooperates with the interior surface of the outer housing to define the second channel for a second fluid. The outer surface of the inner housing and the inner surface of the outer housing each carry a plurality of vanes that interleave but do not touch, each vane of one housing being between two vanes of the other housing. The vanes are curved and the inner surface of the outer housing and the outer surface of the inner housing converge to narrow the second channel. The shape of second channel results in a swirling, accelerating second fluid that will impact the first fluid just past the end of the nozzle where mixing will take place.

Physical sciences: Thermodynamics, cryogenics, and vacuum technology: A compilation

NASA Technical Reports Server (NTRS)

1974-01-01

Technological developments which have potential application outside the aerospace community are reported. A variety of thermodynamic devices including heat pipes and cooling systems are described along with methods of handling cryogenic fluids. Vacuum devices are also described. Pata et information is included.

30 CFR 57.12014 - Handling energized power cables.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...

30 CFR 57.12014 - Handling energized power cables.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...

30 CFR 57.12014 - Handling energized power cables.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...

30 CFR 57.12014 - Handling energized power cables.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...

30 CFR 57.12014 - Handling energized power cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...

78 FR 41993 - Transport Handling Specialists, Inc.-Continuance in Control Exemption-RSL Railroad, LLC

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-12

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35726] Transport Handling Specialists, Inc.--Continuance in Control Exemption--RSL Railroad, LLC Transport Handling Specialists, Inc. (THS), has filed a verified notice of exemption (Notice) under 49 CFR 1180.2(d)(2) to continue in...

76 FR 63714 - Big Spring Rail System, Inc.;Operation Exemption;Transport Handling Specialists, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-13

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35553] Big Spring Rail System, Inc.;Operation Exemption;Transport Handling Specialists, Inc. Big Spring Rail System, Inc. (BSRS...., owned by the City of Big Spring, Tex. (City). BSRS will be operating the line for Transport Handling...

30 CFR 75.1709 - Accumulations of methane and coal dust on surface coal-handling facilities.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Accumulations of methane and coal dust on... Miscellaneous § 75.1709 Accumulations of methane and coal dust on surface coal-handling facilities. [Statutory Provisions] Adequate measures shall be taken to prevent methane and coal dust from accumulating in excessive...

Mechanics of couple-stress fluid coatings

NASA Technical Reports Server (NTRS)

Waxman, A. M.

1982-01-01

The formal development of a theory of viscoelastic surface fluids with bending resistance - their kinematics, dynamics, and rheology are discussed. It is relevant to the mechanics of fluid drops and jets coated by a thin layer of immiscible fluid with rather general rheology. This approach unifies the hydrodynamics of two-dimensional fluids with the mechanics of an elastic shell in the spirit of a Cosserat continuum. There are three distinct facets to the formulation of surface continuum mechanics. Outlined are the important ideas and results associated with each: the kinematics of evolving surface geometries, the conservation laws governing the mechanics of surface continua, and the rheological equations of state governing the surface stress and moment tensors.

Fluid Compressibility Effects on the Dynamic Response of Hydrostatic Journal Bearings

NASA Technical Reports Server (NTRS)

Sanandres, Luis A.

1991-01-01

A theoretical analysis for the dynamic performance characteristics of laminar flow, capillar/orifice compensated hydrostatic journal bearings is presented. The analysis considers in detail the effect of fluid compressibility in the bearing recesses. At high frequency excitations beyond a break frequency, the bearing hydrostatic stiffness increases sharply and it is accompanied by a rapid decrease in direct damping. Also, the potential of pneumatic hammer instability (negative damping) at low frequencies is likely to occur in hydrostatic bearing applications handling highly compressible fluids. Useful design criteria to avoid undesirable dynamic operating conditions at low and high frequencies are determined. The effect of fluid recess compressibility is brought into perspective, and found to be of utmost importance on the entire frequency spectrum response and stability characteristics of hydrostatic/hybrid journal bearings.

Control of Thermal Convection in Layered Fluids Using Magnetic fields

NASA Technical Reports Server (NTRS)

Ramachandran, N.; Leslie, F. W.

2003-01-01

Immiscible fluid layers are found in a host of applications ranging from materials processing, for example the use of encapsulants in float zone crystal growth technique and a buffer layer in industrial Czochralski growth of crystals to prevent Marangoni convection, to heat transfer phenomena in day-to-day processes like the presence of air pockets in heat exchangers. In the microgravity and space processing realm, the exploration of other planets requires the development of enabling technologies in several fronts. The reduction in the gravity level poses unique challenges for fluid handling and heat transfer applications. The present work investigates the efficacy of controlling thermal convective flow using magnetic fluids and magnetic fields. The setup is a two-layer immiscible liquids system with one of the fluids being a diluted ferrofluid (super paramagnetic nano particles dispersed in carrier fluid). Using an external magnetic field one can essentially dial in a volumetric force - gravity level, on the magnetic fluid and thereby affect the system thermo-fluid behavior. The paper will describe the experimental and numerical modeling approach to the problem and discuss results obtained to date.

Does more favourable handling of the cerebrospinal fluid increase the diagnostic sensitivity of Borrelia burgdorferi sensu lato-specific PCR in Lyme neuroborreliosis?

PubMed

Forselv, Kristine J N; Lorentzen, Åslaug R; Ljøstad, Unn; Mygland, Åse; Eikeland, Randi; Kjelland, Vivian; Noraas, Sølvi; Quarsten, Hanne

2018-04-01

Tests for direct detection of Borrelia burgdorferi sensu lato (Bb) in Lyme neuroborreliosis (LNB) are needed. Detection of Bb DNA using PCR is promising, but clinical utility is hampered by low diagnostic sensitivity. We aimed to examine whether diagnostic sensitivity can be improved by the use of larger cerebrospinal fluid (CSF) volumes and faster handling of samples. Patients who underwent CSF examination for LNB were included. We collected two millilitres of CSF for PCR analysis, extracted DNA from the pellets within 24 h and analysed the eluate by two real-time PCR protocols (16S rRNA and OspA). Patients who fulfilled diagnostic criteria for LNB were classified as LNB cases and the rest as controls. Bb DNA in CSF was detected by PCR in seven of 28 adults with LNB. Two were Bb antibody negative. No Bb DNA was detected in CSF from 137 controls. Diagnostic sensitivity was 25% and specificity 100%. There was a non-significant trend towards larger CSF sample volume, faster handling of the sample, shorter duration of symptoms, and higher CSF cell count in the PCR-positive cases. We did not find that optimized handling of CSF increased diagnostic sensitivity of PCR in adults with LNB. However, our case series is small and we hypothesize that the importance of these factors will be clarified in further studies with larger case series and altered study design. PCR for diagnosis of LNB may be useful in cases without Bb antibodies due to short duration of symptoms.

Relativistic analogue of the Newtonian fluid energy equation with nucleosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cardall, Christian Y.

In Newtonian fluid dynamics simulations in which composition has been tracked by a nuclear reaction network, energy generation due to composition changes has generally been handled as a separate source term in the energy equation. Here, a relativistic equation in conservative form for total fluid energy, obtained from the spacetime divergence of the stress-energy tensor, in principle encompasses such energy generation; but it is not explicitly manifest. An alternative relativistic energy equation in conservative form—in which the nuclear energy generation appears explicitly, and that reduces directly to the Newtonian internal+kinetic energy in the appropriate limit—emerges naturally and self-consistently from themore » difference of the equation for total fluid energy and the equation for baryon number conservation multiplied by the average baryon mass m, when m is expressed in terms of contributions from the nuclear species in the fluid, and allowed to be mutable.« less

Rational design of capillary-driven flows for paper-based microfluidics.

PubMed

Elizalde, Emanuel; Urteaga, Raúl; Berli, Claudio L A

2015-05-21

The design of paper-based assays that integrate passive pumping requires a precise programming of the fluid transport, which has to be encoded in the geometrical shape of the substrate. This requirement becomes critical in multiple-step processes, where fluid handling must be accurate and reproducible for each operation. The present work theoretically investigates the capillary imbibition in paper-like substrates to better understand fluid transport in terms of the macroscopic geometry of the flow domain. A fluid dynamic model was derived for homogeneous porous substrates with arbitrary cross-sectional shapes, which allows one to determine the cross-sectional profile required for a prescribed fluid velocity or mass transport rate. An extension of the model to slit microchannels is also demonstrated. Calculations were validated by experiments with prototypes fabricated in our lab. The proposed method constitutes a valuable tool for the rational design of paper-based assays.

Optical trapping for complex fluid microfluidics

NASA Astrophysics Data System (ADS)

Vestad, Tor; Oakey, John; Marr, David W. M.

2004-10-01

Many proposed applications of microfluidics involve the manipulation of complex fluid mixtures such as blood or bacterial suspensions. To sort and handle the constituent particles within these suspensions, we have developed a miniaturized automated cell sorter using optical traps. This microfluidic cell sorter offers the potential to perform chip-top microbiology more rapidly and with less associated hardware and preparation time than other techniques currently available. To realize the potential of this technology in practical clinical and consumer lab-on-a-chip devices however, microscale control of not only particulates but also the fluid phase must be achieved. To address this, we have developed a mechanical fluid control scheme that integrates well with our optical separations approach. We demonstrate here a combined technique, one that employs both mechanical actuation and optical trapping for the precise control of complex suspensions. This approach enables both cell and particle separations as well as the subsequent fluid control required for the completion of complex analyses.

Relativistic analogue of the Newtonian fluid energy equation with nucleosynthesis

DOE PAGES

Cardall, Christian Y.

2017-12-15

In Newtonian fluid dynamics simulations in which composition has been tracked by a nuclear reaction network, energy generation due to composition changes has generally been handled as a separate source term in the energy equation. Here, a relativistic equation in conservative form for total fluid energy, obtained from the spacetime divergence of the stress-energy tensor, in principle encompasses such energy generation; but it is not explicitly manifest. An alternative relativistic energy equation in conservative form—in which the nuclear energy generation appears explicitly, and that reduces directly to the Newtonian internal+kinetic energy in the appropriate limit—emerges naturally and self-consistently from themore » difference of the equation for total fluid energy and the equation for baryon number conservation multiplied by the average baryon mass m, when m is expressed in terms of contributions from the nuclear species in the fluid, and allowed to be mutable.« less

When sticky fluids don't stick: yield-stress fluid drops on heated surfaces

NASA Astrophysics Data System (ADS)

Blackwell, Brendan; Wu, Alex; Ewoldt, Randy

2016-11-01

Yield-stress fluids, including gels and pastes, are effectively fluid at high stress and solid at low stress. In liquid-solid impacts, these fluids can stick and accumulate where they impact; this sticky behavior motivates several applications of these rheologically-complex materials. Here we describe experiments with aqueous yield stress fluids that are more 'sticky' than water at room temperature (e.g. supporting larger coating thicknesses), but are less 'sticky' at higher temperatures. Specifically, we study the conditions for aqueous yield stress fluids to bounce and slide on heated surfaces when water sticks. Here we present high-speed imaging and color interferometry to observe the thickness of the vapor layer between the drop and the surface during both stick and non-stick events. We use these data to gain insight into the physics behind the phenomenon of the yield-stress fluids bouncing and sliding, rather than sticking, on hot surfaces.

Surface catalytic degradation study of two linear perfluoropolyalkylethers at 345 C

NASA Technical Reports Server (NTRS)

Morales, Wilfredo

1987-01-01

Thin-liquid-film degradation studies of two commercially available perfluoropolyalkylether fluids (PFAE) were performed at 345 C, in nitrogen and air atmospheres, on iron and 440 C stainless steel surfaces. It was found that one fluid degraded on both iron and 440 C stainless steel surfaces in an air atmosphere, whereas the other fluid did not degrade. Chemical analysis revealed that the test fluid degraded to lower molecular weight products and that the degradation was accompanied by the formation of a brownish deposit on both the iron and 440 C stainless steel surfaces. Surface analysis of the deposit revealed a susbstantial amount of iron oxide (Fe2O3). It was hypothesized that the fluid which degraded did so because of its acetal structure. The other fluid, lacking the acetal structure, did not degrade.

Flexible Electrostatic Technologies for Capture and Handling, Phase 1

NASA Technical Reports Server (NTRS)

Bryan, Thomas

2015-01-01

Fundamental to many of NASA's in-space transportation missions is the capture and handling of various objects and vehicles in various orbits for servicing, debris disposal, sample retrieval, and assembly without the benefit of sufficient grapple fixtures and docking ports. To perform similar material handling tasks on Earth, pincher grippers, suction grippers, or magnetic chucks are used, but are unable to reliably grip aluminum and composite spacecraft, insulation, radiators, solar arrays, or extra-terrestrial objects in the vacuum of outer space without dedicated handles in the right places. The electronic Flexible Electrostatic Technologies for space Capture and Handling (FETCH) will enable reliable and compliant gripping (soft dock) of practically any object in various orbits or surfaces without dedicated mechanical features, very low impact capture, and built-in proximity sensing without any conventional actuators. Originally developed to handle semiconductor and glass wafers during vacuum chamber processing without contamination, the normal rigid wafer handling chucks are replaced with thin metal foil segments laminated in flexible insulation driven by commercial off-the-shelf solid state, high-voltage power supplies. Preliminary testing in NASA Marshall Space Flight Center's (MSFC's) Flat Floor Robotics Lab demonstrated compliant alignment and gripping with a full-sized, 150-lb microsat mockup and translation before a clean release with a flip of a switch. The flexible electrostatic gripper pads can be adapted to various space applications with different sizes, shapes, and foil electrode layouts even with openings through the gripper pads for addition of guidance sensors or injection of permanent adhesives. With gripping forces estimated between 0.5 and 2.5 lb/in2 or 70-300 lb/ft2 of surface contact, the FETCH can turn on and off rapidly and repeatedly to enable sample handling, soft docking, in-space assembly, precision relocation, and surface translation for accurate anchoring.

Principles of fluid management and stewardship in septic shock: it is time to consider the four D's and the four phases of fluid therapy.

PubMed

Malbrain, Manu L N G; Van Regenmortel, Niels; Saugel, Bernd; De Tavernier, Brecht; Van Gaal, Pieter-Jan; Joannes-Boyau, Olivier; Teboul, Jean-Louis; Rice, Todd W; Mythen, Monty; Monnet, Xavier

2018-05-22

In patients with septic shock, the administration of fluids during initial hemodynamic resuscitation remains a major therapeutic challenge. We are faced with many open questions regarding the type, dose and timing of intravenous fluid administration. There are only four major indications for intravenous fluid administration: aside from resuscitation, intravenous fluids have many other uses including maintenance and replacement of total body water and electrolytes, as carriers for medications and for parenteral nutrition. In this paradigm-shifting review, we discuss different fluid management strategies including early adequate goal-directed fluid management, late conservative fluid management and late goal-directed fluid removal. In addition, we expand on the concept of the "four D's" of fluid therapy, namely drug, dosing, duration and de-escalation. During the treatment of patients with septic shock, four phases of fluid therapy should be considered in order to provide answers to four basic questions. These four phases are the resuscitation phase, the optimization phase, the stabilization phase and the evacuation phase. The four questions are "When to start intravenous fluids?", "When to stop intravenous fluids?", "When to start de-resuscitation or active fluid removal?" and finally "When to stop de-resuscitation?" In analogy to the way we handle antibiotics in critically ill patients, it is time for fluid stewardship.

Heat exchanger with intermediate evaporating and condensing fluid

DOEpatents

Fraas, Arthur P.

1978-01-01

A shell and tube-type heat exchanger, such as a liquid sodium-operated steam generator for use in nuclear reactors, comprises a shell containing a primary fluid tube bundle, a secondary fluid tube bundle at higher elevation, and an intermediate fluid vaporizing at the surface of the primary fluid tubes and condensing at the surface of the secondary fluid tubes.

7 CFR 1124.10 - Producer-handler.

Code of Federal Regulations, 2012 CFR

2012-01-01

... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order... which total route disposition and packaged sales of fluid milk products to other plants during the month... (b)(1) of this section necessary to produce all Class I milk handled (excluding receipts from...

7 CFR 1124.10 - Producer-handler.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order... which total route disposition and packaged sales of fluid milk products to other plants during the month... (b)(1) of this section necessary to produce all Class I milk handled (excluding receipts from...

7 CFR 1124.10 - Producer-handler.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order... which total route disposition and packaged sales of fluid milk products to other plants during the month... (b)(1) of this section necessary to produce all Class I milk handled (excluding receipts from...

7 CFR 1131.10 - Producer-handler.

Code of Federal Regulations, 2012 CFR

2012-01-01

... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating... route disposition and packaged sales of fluid milk products to other plants during the month does not... (b)(1) of this section necessary to produce all Class I milk handled (excluding receipts from...

7 CFR 1131.10 - Producer-handler.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating... route disposition and packaged sales of fluid milk products to other plants during the month does not... (b)(1) of this section necessary to produce all Class I milk handled (excluding receipts from...

7 CFR 1131.10 - Producer-handler.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating... route disposition and packaged sales of fluid milk products to other plants during the month does not... (b)(1) of this section necessary to produce all Class I milk handled (excluding receipts from...

METHODOLOGY TO EVALUATE THE POTENTIAL FOR GROUND WATER CONTAMINATION FROM GEOTHERMAL FLUID RELEASES

EPA Science Inventory

This report provides analytical methods and graphical techniques to predict potential ground water contamination from geothermal energy development. Overflows and leaks from ponds, pipe leaks, well blowouts, leaks from well casing, and migration from injection zones can be handle...

Surface effects on friction-induced fluid heating in nanochannel flows.

PubMed

Li, Zhigang

2009-02-01

We investigate the mechanism of friction-induced fluid heating under the influence of surfaces. The temperature distributions of liquid argon and helium in nanoscale Poiseuille flows are studied through molecular dynamics simulations. It is found that the fluid heating is mainly caused by the viscous friction in the fluid when the external force is small and there is no slip at the fluid-solid interface. When the external force is larger than the fluid-surface binding force, the friction at the fluid-solid interface dominates over the internal friction of the fluid and is the major contribution to fluid heating. An asymmetric temperature gradient in the fluid is developed in the case of nonidentical walls and the general temperature gradient may change sign as the dominant heating factor changes from internal to interfacial friction with increasing external force. The effect of temperature on the fluid heating is also discussed.

The Role of Nano-TiO2 Lubricating Fluid on the Hot Rolled Surface and Metallographic Structure of SS41 Steel

PubMed Central

Meng, Yanan; Sun, Jianlin; Wu, Ping; Dong, Chang; Yan, Xudong

2018-01-01

In this paper, nano-TiO2lubricating fluid was chosen as an advanced rolling lubricant to investigate its effect on the hot rolled surface and metallographic structure of SS41 steel strips. The tribological performances of nano-TiO2 lubricating fluid were measured by a four-ball tribotester. The hot rolling experiments under different lubrication conditions were carried out by a four-high rolling mill. The surface morphology, oxide scales and metallographic structure after hot rolling were observed using a confocal laser scanning microscope and scanning electron microscope (SEM), respectively. The composition of surface attachments was analyzed with X-ray photoelectron spectroscopy (XPS). The results indicate that the nano-TiO2 lubricating fluid has a better tribological performance. The surface defects on the hot rolled surface could be decreased. The phase composition of the surface still appears as a mixture of ferrite and pearlite. The surface of steel strips is not micro-alloyed with titanium as predicted. Additionally, the grain size of rolled steel strips which were lubricated with the nano-TiO2lubricating fluid decreased by nearly 50%, compared with traditional lubricating fluid. Furthermore, it was found that the thickness of the oxide layers on the surface reduced, whilst the Rockwell hardness of the oxide layers was enhanced as nano-TiO2 lubricating fluid was applied. PMID:29462937

The Role of Nano-TiO2 Lubricating Fluid on the Hot Rolled Surface and Metallographic Structure of SS41 Steel.

PubMed

Meng, Yanan; Sun, Jianlin; Wu, Ping; Dong, Chang; Yan, Xudong

2018-02-16

In this paper, nano-TiO2lubricating fluid was chosen as an advanced rolling lubricant to investigate its effect on the hot rolled surface and metallographic structure of SS41 steel strips. The tribological performances of nano-TiO2 lubricating fluid were measured by a four-ball tribotester. The hot rolling experiments under different lubrication conditions were carried out by a four-high rolling mill. The surface morphology, oxide scales and metallographic structure after hot rolling were observed using a confocal laser scanning microscope and scanning electron microscope (SEM), respectively. The composition of surface attachments was analyzed with X-ray photoelectron spectroscopy (XPS). The results indicate that the nano-TiO2 lubricating fluid has a better tribological performance. The surface defects on the hot rolled surface could be decreased. The phase composition of the surface still appears as a mixture of ferrite and pearlite. The surface of steel strips is not micro-alloyed with titanium as predicted. Additionally, the grain size of rolled steel strips which were lubricated with the nano-TiO2lubricating fluid decreased by nearly 50%, compared with traditional lubricating fluid. Furthermore, it was found that the thickness of the oxide layers on the surface reduced, whilst the Rockwell hardness of the oxide layers was enhanced as nano-TiO2 lubricating fluid was applied.

Ultrasound for non-invasive fluid droplet detection inside a sealed container

NASA Astrophysics Data System (ADS)

Glass, S. W.; Good, M. S.; Roy, S.; Luzi, F.

2017-02-01

Ultrasound has long been known to be capable of measuring water level. Zero-degree ultrasound transducers may be used to send an L-wave through the fluid and receive a reflected signal from the fluid/gas interface surface. The level of the fluid is proportional to the sound wave time of flight to traverse the water path. This approach may even be used from outside the fluid containment wall by sending the wave through the tank or pipe bottom. The approach, however, does not work well if there is only a thin layer of fluid consisting of one or two millimeters or even only a few droplets. Surface waves are also known to be sensitive to the presence or absence of fluid on a surface. A surface wave may be transmitted a significant distance by a transmitting transducer and then received by a similar transducer. If the surface along the wave path is wet with even a few droplets of fluid, the surface wave may be significantly attenuated. Generating and measuring such a surface wave from the opposite side of a tank or pipe containment wall and separating the near-wall surface wave from the far-wall surface wave, however, is more challenging. The feasibility of an approach for producing a surface wave on the opposite side of a steel plate to sense the presence or absence of fluid is discussed. This approach is supported by 2-D finite element modeling of the measurement configuration and by empirical demonstration of the technique's sensitivity. This technique was developed for measurement of a very small amount of fluid that may condense within a used nuclear fuel canister after it cools for several years. Early detection of fluid would provide advance warning of potential degradation to internal components in time for mitigation or management of the waste inside that container. Other potential applications include non-intrusive detection of trace liquids within any sealed container, within inaccessible plena of aircrafts or within other inaccessible complex welded skin structures.

Deformation of Fluid Column by Action of Axial Vibration and Some Aspects of High-Rate Thermocapillary Convection

NASA Technical Reports Server (NTRS)

Feonychev, Alexander I.; Kalachinskaya, Irina S.; Pokhilko, Victor I.

1996-01-01

The deformation of the fluid column by an action of a low-frequency vibration is considered. It is shown that behavior of the free fluid surface depends on the frequency of applied vibration and its amplitude. In the area of very low frequencies when fluid has time to comment on travel of bounding solid walls limiting column, the harmonical oscillations of free surface with given frequency are observed. With increase of vibration frequency the steady-state relief on free fluid surface is formed. If the amplitude of vibration is very small and the frequency corresponding to the first peak in the vibration spectrum on the Mir orbital station, the deformation of free surface tends to zero. Fluid flow induced thermocapillary effect on deformed free surface is more unstable as in the case of smooth cylindrical surface. It was shown that width of heating zone affects very essentially the flow pattern and transition to oscillatory regime of thermocapillary convection.

Swirling structure for mixing two concentric fluid flows at nozzle outlet

DOEpatents

Mensink, D.L.

1993-07-20

A nozzle device is described for causing two fluids to mix together. In particular, a spray nozzle comprises two hollow, concentric housings, an inner housing and an outer housing. The inner housing has a channel formed therethrough for a first fluid. Its outer surface cooperates with the interior surface of the outer housing to define the second channel for a second fluid. The outer surface of the inner housing and the inner surface of the outer housing each carry a plurality of vanes that interleave but do not touch, each vane of one housing being between two vanes of the other housing. The vanes are curved and the inner surface of the outer housing and the outer surface of the inner housing converge to narrow the second channel. The shape of second channel results in a swirling, accelerating second fluid that will impact the first fluid just past the end of the nozzle where mixing will take place.

Direct numerical simulation of variable surface tension flows using a Volume-of-Fluid method

NASA Astrophysics Data System (ADS)

Seric, Ivana; Afkhami, Shahriar; Kondic, Lou

2018-01-01

We develop a general methodology for the inclusion of a variable surface tension coefficient into a Volume-of-Fluid based Navier-Stokes solver. This new numerical model provides a robust and accurate method for computing the surface gradients directly by finding the tangent directions on the interface using height functions. The implementation is applicable to both temperature and concentration dependent surface tension coefficient, along with the setups involving a large jump in the temperature between the fluid and its surrounding, as well as the situations where the concentration should be strictly confined to the fluid domain, such as the mixing of fluids with different surface tension coefficients. We demonstrate the applicability of our method to the thermocapillary migration of bubbles and the coalescence of drops characterized by a different surface tension coefficient.

Dropwise Condensation of Low Surface Tension Fluids on Omniphobic Surfaces

PubMed Central

Rykaczewski, Konrad; Paxson, Adam T.; Staymates, Matthew; Walker, Marlon L.; Sun, Xiaoda; Anand, Sushant; Srinivasan, Siddarth; McKinley, Gareth H.; Chinn, Jeff; Scott, John Henry J.; Varanasi, Kripa K.

2014-01-01

Compared to the significant body of work devoted to surface engineering for promoting dropwise condensation heat transfer of steam, much less attention has been dedicated to fluids with lower interfacial tension. A vast array of low-surface tension fluids such as hydrocarbons, cryogens, and fluorinated refrigerants are used in a number of industrial applications, and the development of passive means for increasing their condensation heat transfer coefficients has potential for significant efficiency enhancements. Here we investigate condensation behavior of a variety of liquids with surface tensions in the range of 12 to 28 mN/m on three types of omniphobic surfaces: smooth oleophobic, re-entrant superomniphobic, and lubricant-impregnated surfaces. We demonstrate that although smooth oleophobic and lubricant-impregnated surfaces can promote dropwise condensation of the majority of these fluids, re-entrant omniphobic surfaces became flooded and reverted to filmwise condensation. We also demonstrate that on the lubricant-impregnated surfaces, the choice of lubricant and underlying surface texture play a crucial role in stabilizing the lubricant and reducing pinning of the condensate. With properly engineered surfaces to promote dropwise condensation of low-surface tension fluids, we demonstrate a four to eight-fold improvement in the heat transfer coefficient. PMID:24595171

Dropwise condensation of low surface tension fluids on omniphobic surfaces.

PubMed

Rykaczewski, Konrad; Paxson, Adam T; Staymates, Matthew; Walker, Marlon L; Sun, Xiaoda; Anand, Sushant; Srinivasan, Siddarth; McKinley, Gareth H; Chinn, Jeff; Scott, John Henry J; Varanasi, Kripa K

2014-03-05

Compared to the significant body of work devoted to surface engineering for promoting dropwise condensation heat transfer of steam, much less attention has been dedicated to fluids with lower interfacial tension. A vast array of low-surface tension fluids such as hydrocarbons, cryogens, and fluorinated refrigerants are used in a number of industrial applications, and the development of passive means for increasing their condensation heat transfer coefficients has potential for significant efficiency enhancements. Here we investigate condensation behavior of a variety of liquids with surface tensions in the range of 12 to 28 mN/m on three types of omniphobic surfaces: smooth oleophobic, re-entrant superomniphobic, and lubricant-impregnated surfaces. We demonstrate that although smooth oleophobic and lubricant-impregnated surfaces can promote dropwise condensation of the majority of these fluids, re-entrant omniphobic surfaces became flooded and reverted to filmwise condensation. We also demonstrate that on the lubricant-impregnated surfaces, the choice of lubricant and underlying surface texture play a crucial role in stabilizing the lubricant and reducing pinning of the condensate. With properly engineered surfaces to promote dropwise condensation of low-surface tension fluids, we demonstrate a four to eight-fold improvement in the heat transfer coefficient.

Fundamental Degradation Mechanisms of Multi-Functional Nanoengineered Surfaces

DTIC Science & Technology

2018-04-08

surface tension fluids with widely used lubricants for designing LIS. We considered a wide range of low surface tension fluids (12 to 48 mN/m) and...selection in designing stable LIS for the low surface tension fluids. Lastly, using steady state condensation experiments, we show that polymeric...polymeric coating to the high surface energy substrate and mechanical delamination of the coating. This finding will be key to future design

Thermodynamic processes associated with frostbite in the handling of liquid nitrogen

NASA Astrophysics Data System (ADS)

Johnson, W. L.; Cook, C. R.

2014-01-01

It is often taught that exposure to liquid nitrogen will cause frostbite or more severe damage to exposed skin tissue. However, it is also demonstrated that a full hand can be briefly immersed in liquid nitrogen without damage. To better understand and possibly visualize the effects of human tissue exposure to liquid nitrogen, a series of tests were conducted using simulated hands and arms composed of molded gelatin forms. The simulated hands and arms were immersed, sprayed, or splashed with liquid nitrogen both with and without state of the art personal protective equipment. Thermocouples were located within the test articles to allow for thermal mapping during the freezing process. The study is aimed to help understand frostbite hazards and the time constants involved with the handling of liquid nitrogen to improve future safety protocols for the safe handling of cryogenic fluids. Results of the testing also show the limits to handling liquid nitrogen while using various means of protection.

Sodium Handling Technology and Engineering Design of the Madison Dynamo Experiment.

NASA Astrophysics Data System (ADS)

Kendrick, R.; Forest, C. B.; O'Connell, R.; Wright, A.; Robinson, K.

1998-11-01

A new liquid metal MHD experiment is being constructed at the University of Wisconsin to test several key predictions of dynamo theory: magnetic instabilities driven by sheared flow, the effects of turbulence on current generation, and the back-reaction of the self-generated magnetic field on the fluid motion which brings saturation. This presentation describes the engineering design of the experiment, which is a 0.5 m radius spherical vessel, filled with liquid sodium at 150 degrees Celsius. The experiment is designed to achieve a magnetic Reynolds number in excess of 100, which requires approximately 80 Hp of mechanical drive, producing flow velocities in sodium of 15 m/s through impellers. Handling liquid sodium offers a number of technical challenges, but routine techniques have been developed over the past several decades for safely handling large quantities for the fast breeder reactor. The handling strategy is discussed, technical details concerning seals and pressurazation are presented, and safety elements are highlighted.

Preliminary design of two Space Shuttle fluid physics experiments

NASA Technical Reports Server (NTRS)

Gat, N.; Kropp, J. L.

1984-01-01

The mid-deck lockers of the STS and the requirements for operating an experiment in this region are described. The design of the surface tension induced convection and the free surface phenomenon experiments use a two locker volume with an experiment unique structure as a housing. A manual mode is developed for the Surface Tension Induced Convection experiment. The fluid is maintained in an accumulator pre-flight. To begin the experiment, a pressurized gas drives the fluid into the experiment container. The fluid is an inert silicone oil and the container material is selected to be comparable. A wound wire heater, located axisymmetrically above the fluid can deliver three wattages to a spot on the fluid surface. These wattages vary from 1-15 watts. Fluid flow is observed through the motion of particles in the fluid. A 5 mw He/Ne laser illuminates the container. Scattered light is recorded by a 35mm camera. The free surface phenomena experiment consists of a trapezoidal cell which is filled from the bottom. The fluid is photographed at high speed using a 35mm camera which incorporated the entire cell length in the field of view. The assembly can incorporate four cells in one flight. For each experiment, an electronics block diagram is provided. A control panel concept is given for the surface induced convection. Both experiments are within the mid-deck locker weight and c-g limits.

Dynamics of viscous liquid bridges inside microchannels subject to external oscillatory flow

NASA Astrophysics Data System (ADS)

Ahmadlouydarab, Majid; Azaiez, Jalel; Chen, Zhangxin

2015-02-01

We report on two-dimensional simulations of liquid bridges' dynamics inside microchannels of uniform wettability and subject to an external oscillatory flow rate. The oscillatory flow results in a zero net flow rate and its effects are compared to those of a stationary system. To handle the three phase contact lines motion, Cahn-Hilliard diffuse-interface formulation was used and the flow equations were solved using the finite element method with adaptively refined unstructured grids. The results indicate that the liquid bridge responds in three different ways depending on the substrate wettability properties and the frequency of the oscillatory flow. In particular below a critical frequency, the liquid bridge will rupture when the channel walls are philic or detach from the surface when they are phobic. However, at high frequencies, the liquid bridge shows a perpetual periodic oscillatory motion for both philic and phobic surfaces. Furthermore, an increase in the frequency of the flow velocity results in stabilization effects and a behavior approaching that of the stationary system where no rupture or detachment can be observed. This stable behavior is the direct result of less deformation of the liquid bridge due to the fast flow direction change and motion of contact lines on the solid substrate. Moreover, it was found that the flow velocity is out of phase with the footprint and throat lengths and that the latter two also show a phase difference. These differences were explained in terms of the motion of the two contact lines on the solid substrates and the deformation of the two fluid-fluid interfaces.

Dynamics of viscous liquid bridges inside microchannels subject to external oscillatory flow.

PubMed

Ahmadlouydarab, Majid; Azaiez, Jalel; Chen, Zhangxin

2015-02-01

We report on two-dimensional simulations of liquid bridges' dynamics inside microchannels of uniform wettability and subject to an external oscillatory flow rate. The oscillatory flow results in a zero net flow rate and its effects are compared to those of a stationary system. To handle the three phase contact lines motion, Cahn-Hilliard diffuse-interface formulation was used and the flow equations were solved using the finite element method with adaptively refined unstructured grids. The results indicate that the liquid bridge responds in three different ways depending on the substrate wettability properties and the frequency of the oscillatory flow. In particular below a critical frequency, the liquid bridge will rupture when the channel walls are philic or detach from the surface when they are phobic. However, at high frequencies, the liquid bridge shows a perpetual periodic oscillatory motion for both philic and phobic surfaces. Furthermore, an increase in the frequency of the flow velocity results in stabilization effects and a behavior approaching that of the stationary system where no rupture or detachment can be observed. This stable behavior is the direct result of less deformation of the liquid bridge due to the fast flow direction change and motion of contact lines on the solid substrate. Moreover, it was found that the flow velocity is out of phase with the footprint and throat lengths and that the latter two also show a phase difference. These differences were explained in terms of the motion of the two contact lines on the solid substrates and the deformation of the two fluid-fluid interfaces.

Human pathogens, nosocomial infections, heat-sensitive textile implants, and an innovative approach to deal with them.

PubMed

Cinquemani, Claudio

2011-01-01

Implantable polymers, as used for biomedical applications, inherently have to be sterile. Nonetheless, most implants, particularly those comprised of biomaterials developed in recent years for tissue engineering, are heat sensitive. Therefore, use of hazardous (radio)chemicals--due to lack of alternative methods--is still state of the art for sterilization processes. The drawbacks of these techniques, both drastic and well known, lead to the demand for an alternative sterilization method, which is equally obvious and urgent. High-pressure fluid treatment is a low-temperature technique that is already in use for pasteurization of liquid food products. This paper explores inactivation of vegetative microorganisms, spores, and endotoxins adherent to solid surfaces using compressed CO(2). Pressures ranging from 50 to 100 bar and temperatures from 25 °C to 50 °C were explored to investigate liquid, gaseous or supercritical state. Analysis of variance (ANOVA) and statistical modeling were used to identify the optimum parameter settings for inactivation of pathogenic bacteria and fungi (Candida albicans, Staphylococcus aureus). The addition of small amounts of ozone ensures inactivation of persistent spores (Bacillus stearothermophilus, B. subtilis) up to 10(6) cfu/ml, while endotoxins remain in practically unchanged concentration on the polymer surface. We then discuss environmental issues of the process and inactivation mechanisms. The replacement of conventional chemicals with nonpersistent ones resolves organizational and safety-related issues and protects natural resources as well as handling staff. The pressurized-fluid-based method exhibits mild treatment parameters, thus protecting sensitive textures. Finally, an outlook on possible applications of this innovative technique is presented.

Measurement of tritium with plastic scintillator surface improvement with plasma treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoshihara, Y.; Furuta, E.; Ohyama, R.I.

2015-03-15

Tritium is usually measured by using a liquid scintillation counter. However, liquid scintillator used for measurement will become radioactive waste fluid. To solve this issue, we have developed a method of measuring tritium samples with plasma-treated plastic scintillator (PS)sheets (Plasma method). The radioactive sample is held between 2 PS sheets and the whole is enclosed in a a low-potassium glass vial. With the Plasma method of 2-min plasma treatment, we have obtained measurement efficiency of 48 ± 2 % for 2 min measurement of tritium except for tritiated water. The plasma treatment makes the PS surface rough and hydrophilic whichmore » contributes to improve the contact between tritium and PS. On the other hand, it needed almost 6 hours to obtain constant measurement efficiency. The reason was that the dry-up handling in the vial needed longer time to vaporize H{sub 2}O molecules than in the air. We tried putting silica gel beads into vials to remove H{sub 2}O molecules from PS sheet surface quickly. The silica gel beads worked well and we got constant measurement efficiency within 1-3 hours. Also, we tried using other kinds of PS treated with plasma to obtain higher measurement efficiencies of tritium samples.« less

Oscillatory motion based measurement method and sensor for measuring wall shear stress due to fluid flow

DOEpatents

Armstrong, William D [Laramie, WY; Naughton, Jonathan [Laramie, WY; Lindberg, William R [Laramie, WY

2008-09-02

A shear stress sensor for measuring fluid wall shear stress on a test surface is provided. The wall shear stress sensor is comprised of an active sensing surface and a sensor body. An elastic mechanism mounted between the active sensing surface and the sensor body allows movement between the active sensing surface and the sensor body. A driving mechanism forces the shear stress sensor to oscillate. A measuring mechanism measures displacement of the active sensing surface relative to the sensor body. The sensor may be operated under periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor measurably changes the amplitude or phase of the motion of the active sensing surface, or changes the force and power required from a control system in order to maintain constant motion. The device may be operated under non-periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor change the transient motion of the active sensor surface or change the force and power required from a control system to maintain a specified transient motion of the active sensor surface.

46 CFR 56.30-3 - Piping joints (reproduces 110).

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 2 2011-10-01 2011-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... joint tightness, mechanical strength and the nature of the fluid handled. ...

46 CFR 56.30-3 - Piping joints (reproduces 110).

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 2 2013-10-01 2013-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... joint tightness, mechanical strength and the nature of the fluid handled. ...

46 CFR 56.30-3 - Piping joints (reproduces 110).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... joint tightness, mechanical strength and the nature of the fluid handled. ...

46 CFR 56.30-3 - Piping joints (reproduces 110).

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 2 2012-10-01 2012-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... joint tightness, mechanical strength and the nature of the fluid handled. ...

46 CFR 56.30-3 - Piping joints (reproduces 110).

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 2 2014-10-01 2014-10-01 false Piping joints (reproduces 110). 56.30-3 Section 56.30-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND... joint tightness, mechanical strength and the nature of the fluid handled. ...

Magnetic field dependent measurement techniques of surface tension of magnetic fluid at an air interface

NASA Astrophysics Data System (ADS)

Nair, Nishant; Virpura, Hiral; Patel, Rajesh

2015-06-01

We describe here two measurement techniques to determine surface tension of magnetic fluid. (i) magneti c field dependent capillary rise method and (ii) Taylor wavelength method in which the distance between the consecutive stable spikes was measured and then surface tension was calculated. The surface tension measurements from both the methods are compared. It is observed that surface tension of magnetic fluid increases with increase in magnetic field due to field dependent structure formation in magnetic fluid at an air interface. We have also measured magnetic susceptibility and surface tension for different volume fractions. The measurement of magnetic susceptibility is carried out using Quincke's experimental techniques.

Neural Control Mechanisms and Body Fluid Homeostasis

NASA Technical Reports Server (NTRS)

Johnson, Alan Kim

1998-01-01

The goal of the proposed research was to study the nature of afferent signals to the brain that reflect the status of body fluid balance and to investigate the central neural mechanisms that process this information for the activation of response systems which restore body fluid homeostasis. That is, in the face of loss of fluids from intracellular or extracellular fluid compartments, animals seek and ingest water and ionic solutions (particularly Na(+) solutions) to restore the intracellular and extracellular spaces. Over recent years, our laboratory has generated a substantial body of information indicating that: (1) a fall in systemic arterial pressure facilitates the ingestion of rehydrating solutions and (2) that the actions of brain amine systems (e.g., norepinephrine; serotonin) are critical for precise correction of fluid losses. Because both acute and chronic dehydration are associated with physiological stresses, such as exercise and sustained exposure to microgravity, the present research will aid in achieving a better understanding of how vital information is handled by the nervous system for maintenance of the body's fluid matrix which is critical for health and well-being.

A classical density functional theory for the asymmetric restricted primitive model of ionic liquids

NASA Astrophysics Data System (ADS)

Lu, Hongduo; Nordholm, Sture; Woodward, Clifford E.; Forsman, Jan

2018-05-01

A new three-parameter (valency, ion size, and charge asymmetry) model, the asymmetric restricted primitive model (ARPM) of ionic liquids, has recently been proposed. Given that ionic liquids generally are composed of monovalent species, the ARPM effectively reduces to a two-parameter model. Monte Carlo (MC) simulations have demonstrated that the ARPM is able to reproduce key properties of room temperature ionic liquids (RTILs) in bulk and at charged surfaces. The relatively modest complexity of the model raises the possibility, which is explored here, that a classical density functional theory (DFT) could resolve its properties. This is relevant because it might generate great improvements in terms of both numerical efficiency and understanding in the continued research of RTILs and their applications. In this report, a DFT for rod-like molecules is proposed as an approximate theoretical tool for an ARPM fluid. Borrowing data on the ion pair fraction from a single bulk simulation, the ARPM is modelled as a mixture of dissociated ions and connected ion pairs. We have specifically studied an ARPM where the hard-sphere diameter is 5 Å, with the charge located 1 Å from the hard-sphere centre. We focus on fluid structure and electrochemical behaviour of this ARPM fluid, into which a model electrode is immersed. The latter is modelled as a perfect conductor, and surface polarization is handled by the method of image charges. Approximate methods, which were developed in an earlier study, to take image interactions into account, are also incorporated in the DFT. We make direct numerical comparisons between DFT predictions and corresponding simulation data. The DFT theory is implemented both in the normal mean field form with respect to the electrostatic interactions and in a correlated form based on hole formation by both steric repulsions and ion-ion Coulomb interactions. The results clearly show that ion-ion correlations play a very important role in the screening of the charged surfaces by our ARPM ionic liquid. We have studied electrostatic potentials and ion density profiles as well the differential capacitance. The mean-field DFT fails to reproduce these properties, but the inclusion of ion-ion correlation by a simple approximate treatment yields quite reasonable agreement with the corresponding simulation results. An interesting finding is that there appears to be a surface phase transition at relatively low surface charge which is readily explored by DFT, but seen also in the MC simulations at somewhat higher asymmetry.

THE PASSAGE OF MARKED IONS INTO TISSUES AND FLUIDS OF THE REPRODUCTIVE TRACT OF PREGNANT RABBITS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, J.P.; Boursnell, J.C.; Lutwak-Mann, C.

1959-10-31

Rapid changes were demonstrated in the uptake of labeled ions both in the developing embryo and in the endometrium, mesodermal placental folds, and other closely associated tissues and fluids following the intravenous injection of labeled ions in pregnant rabbits. Phosphorus-32, sulfur-85, sodium-24, iodine- 131, and potassium-42 were used as tracers. A number of new techniques were developed to obtain, weigh, and handle the extremely small samples. The influence of exogenous materials on the early development of fetuses is discussed briefly. (C.R.)

Physically-Based Rendering of Particle-Based Fluids with Light Transport Effects

NASA Astrophysics Data System (ADS)

Beddiaf, Ali; Babahenini, Mohamed Chaouki

2018-03-01

Recent interactive rendering approaches aim to efficiently produce images. However, time constraints deeply affect their output accuracy and realism (many light phenomena are poorly or not supported at all). To remedy this issue, in this paper, we propose a physically-based fluid rendering approach. First, while state-of-the-art methods focus on isosurface rendering with only two refractions, our proposal (1) considers the fluid as a heterogeneous participating medium with refractive boundaries, and (2) supports both multiple refractions and scattering. Second, the proposed solution is fully particle-based in the sense that no particles transformation into a grid is required. This interesting feature makes it able to handle many particle types (water, bubble, foam, and sand). On top of that, a medium with different fluids (color, phase function, etc.) can also be rendered.

Surface tension driven flow in glass melts and model fluids

NASA Technical Reports Server (NTRS)

Mcneil, T. J.; Cole, R.; Subramanian, R. S.

1982-01-01

Surface tension driven flow has been investigated analytically and experimentally using an apparatus where a free column of molten glass or model fluids was supported at its top and bottom faces by solid surfaces. The glass used in the experiments was sodium diborate, and the model fluids were silicone oils. In both the model fluid and glass melt experiments, conclusive evidence was obtained to prove that the observed flow was driven primarily by surface tension forces. The experimental observations are in qualitative agreement with predictions from the theoretical model.

Study of the flow field past dimpled aerodynamic surfaces: numerical simulation and experimental verification

NASA Astrophysics Data System (ADS)

Binci, L.; Clementi, G.; D'Alessandro, V.; Montelpare, S.; Ricci, R.

2017-11-01

This work presents the study of the flow field past of dimpled laminar airfoil. Fluid dynamic behaviour of these elements has been not still deeply studied in the scientific community. Therefore Computational Fluid-Dynamics (CFD) is here used to analyze the flow field induced by dimples on the NACA 64-014A laminar airfoil at Re = 1.75 · 105 at α = 0°. Reynolds Averaged Navier-Stokes (RANS) equations and Large-Eddy Simulations (LES) were compared with wind tunnel measurements in order to evaluate their effectiveness in the modeling this kind of flow field. LES equations were solved using a specifically developed OpenFOAM solver adopting an L-stable Singly Diagonally Implicit Runge-Kutta (SDIRK) technique with an iterated PISO-like procedure for handling pressure-velocity coupling within each RK stage. Dynamic Smagorinsky subgrid model was employed. LES results provided good agreement with experimental data, while RANS equations closed with \\[k-ω -γ -\\overset{}{\\mathop{{{\\operatorname{Re}}θ, \\text{t}}}} \\] approach overstimates laminar separation bubble (LSB) extension of dimpled and un-dimpled configurations. Moreover, through skin friction coefficient analysis, we found a different representation of the turbulent zone between the numerical models; indeed, with RANS model LSB seems to be divided in two different parts, meanwhile LES model shows a LSB global reduction.

[Pre-analytical quality in fluid samples cytopathology: Results of a survey from the French Society of Clinical Cytology].

PubMed

Courtade-Saïdi, Monique; Fleury Feith, Jocelyne

2015-10-01

The pre-analytical step includes sample collection, preparation, transportation and storage in the pathology unit where the diagnosis is performed. The pathologist ensures that pre-analytical conditions are in line with expectations. The lack of standardization for handling cytological samples makes this pre-analytical step difficult to harmonize. Moreover, this step depends on the nature of the sample: fresh liquid or fixed material, air-dried smears, liquid-based cytology. The aim of the study was to review the different practices in French structures of pathology on the pre-analytical phase concerning cytological fluids such as broncho-alveolar lavage (BALF), serous fluids and urine. A survey was conducted on the basis of the pre-analytical chapter of the ISO 15189 and sent to 191 French pathological structures (105 public and 86 private). Fifty-six laboratories replied to the survey. Ninety-five per cent have a computerized management system and 70% a manual on sample handling. The general instructions requested for the patients and sample identification were highly correctly filled with a short time routing and additional tests prescription. By contrast, information are variable concerning the clinical information requested and the type of tubes for collecting fluids and the volumes required as well as the actions taken in case of non-conformity. For the specific items concerning BALF, serous fluids and urine, this survey has shown a great heterogeneity according to sample collection, fixation and of clinical information. This survey demonstrates that the pre-analytical quality for BALF, serous fluids and urine is not optimal and that some corrections of the practices are recommended with a standardization of numerous steps in order to increase the reproducibility of additional tests such as immunocytochemistry, cytogenetic and molecular biology. Some recommendations have been written. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Bacterial Contamination and Disinfection Status of Laryngoscopes Stored in Emergency Crash Carts

PubMed Central

Lee, Jung Won; Shin, Hee Bong; Lee, In Kyung

2017-01-01

Objectives To identify bacterial contamination rates of laryngoscope blades and handles stored in emergency crash carts by hospital and area according to the frequency of intubation attempts. Methods One hundred forty-eight handles and 71 blades deemed ready for patient use from two tertiary hospitals were sampled with sterile swabs using a standardized rolling technique. Samples were considered negative (not contaminated) if no colonies were present on the blood agar plate after an 18-hour incubation period. Samples were stratified by hospital and according to the frequency of intubation attempts (10 attempts per year) using the χ2-test and Fisher exact test. Results One or more species of bacteria were isolated from 4 (5.6%) handle tops, 20 (28.2%) handles with knurled surfaces, and 27 (18.2%) blades. No significant differences were found in microbial contamination levels on the handle tops and blades between the two hospitals and two areas according to the frequency of intubation attempts. However, significant differences were found between the two hospitals and two areas in the level of microbial contamination on the handles with knurled surfaces (p<0.05). Conclusions Protocols and policies must be reviewed to standardize procedures to clean and disinfect laryngoscope blades and handles; handles should be re-designed to eliminate points of contact with the blade; and single-use, one-piece laryngoscopes should be introduced. PMID:28605891

Performance of journal bearings with semi-compressible fluids

NASA Technical Reports Server (NTRS)

Carpino, M.; Peng, J.-P.

1991-01-01

Cryogenic fluids in isothermal rigid surface and foil type journal bearings can sometimes be treated as semicompressible fluids. In these applications, the fluid density is a function of the pressure. At low pressures, the fluids can change from a liquid to a saturated liquid-vapor phase. The performance of a rigid surface journal bearing with an idealized semicompressible fluid is discussed. Pressure solutions are based upon a Reynolds equation which includes the effects of a compressibility via the bulk modulus of the fluid. Results are contrasted with the performance of isothermal constant property incompressible fluids.

Study of Surface Wave Propagation in Fluid-Saturated Porous Solids.

NASA Astrophysics Data System (ADS)

Azcuaga, Valery Francisco Godinez

1995-01-01

This study addresses the surface wave propagation phenomena on fluid-saturated porous solids. The analytical method for calculation of surface wave velocities (Feng and Johnson, JASA, 74, 906, 1983) is extended to the case of a porous solid saturated with a wetting fluid in contact with a non-wetting fluid, in order to study a material combination suitable for experimental investigation. The analytical method is further extended to the case of a non-wetting fluid/wetting fluid-saturated porous solid interface with an arbitrary finite surface stiffness. These extensions of the analytical method allows to theoretically study surface wave propagation phenomena during the saturation process. A modification to the 2-D space-time reflection Green's function (Feng and Johnson, JASA, 74, 915, 1983) is introduced in order to simulate the behavior of surface wave signals detected during the experimental investigation of surface wave propagation on fluid-saturated porous solids (Nagy, Appl. Phys. Lett., 60, 2735, 1992). This modification, together with the introduction of an excess attenuation for the Rayleigh surface mode, makes it possible to explain the apparent velocity changes observed on the surface wave signals during saturation. Experimental results concerning the propagation of surface waves on an alcohol-saturated porous glass are presented. These experiments were performed at frequencies of 500 and 800 kHz and show the simultaneous propagation of the two surface modes predicted by the extended analytical method. Finally an analysis of the displacements associated with the different surface modes is presented. This analysis reveals that it is possible to favor the generation of the Rayleigh surface mode or of the slow surface mode, simply by changing the type of transducer used in the generation of surface waves. Calculations show that a shear transducer couples more energy into the Rayleigh mode, whereas a longitudinal transducer couples more energy into the slow surface mode. Experimental results obtained with the modified experimental system show a qualitative agreement with the theoretical predictions.

Dry deposition of pollutant and marker particles onto live mouse airway surfaces enhances monitoring of individual particle mucociliary transit behaviour.

PubMed

Donnelley, Martin; Morgan, Kaye S; Siu, Karen K W; Parsons, David W

2012-07-01

Particles suspended in the air are inhaled during normal respiration and unless cleared by airway defences, such as the mucociliary transit (MCT) system, they can remain and affect lung and airway health. Synchrotron phase-contrast X-ray imaging (PCXI) methods have been developed to non-invasively monitor the behaviour of individual particles in live mouse airways and in previous studies the MCT behaviour of particles and fibres in the airways of live mice after deposition in a saline carrier fluid have been examined. In this study a range of common respirable pollutant particles (lead dust, quarry dust and fibreglass fibres) as well as marker particles (hollow glass micro-spheres) were delivered into the trachea of live mice using a dry powder insufflator to more accurately mimic normal environmental particulate exposure and deposition via inhalation. The behaviour of the particles once delivered onto the airway surface was tracked over a five minute period via PCXI. All particles were visible after deposition. Fibreglass fibres remained stationary throughout while all other particle types transited the tracheal surface throughout the imaging period. In all cases the majority of the particle deposition and any airway surface activity was located close to the dorsal tracheal wall. Both the individual and bulk motions of the glass bead marker particles were visible and their behaviour enabled otherwise hidden MCT patterns to be revealed. This study verified the value of PCXI for examining the post-deposition particulate MCT behaviour in the mouse trachea and highlighted that MCT is not a uniform process as suggested by radiolabel studies. It also directly revealed the advantages of dry particle delivery for establishing adequate particulate presence for visualizing MCT behaviour. The MCT behaviour and rate seen after dry particle delivery was different from that in previous carrier-fluid studies. It is proposed that dry particle delivery is essential for producing environmentally realistic particle deposition and studying how living airway surfaces handle different types of inhaled particles by MCT processes.

Effects of surface tension and intraluminal fluid on mechanics of small airways.

PubMed

Hill, M J; Wilson, T A; Lambert, R K

1997-01-01

Airway constriction is accompanied by folding of the mucosa to form ridges that run axially along the inner surface of the airways. The mucosa has been modeled (R. K. Lambert. J. Appl. Physiol. 71:666-673, 1991) as a thin elastic layer with a finite bending stiffness, and the contribution of its bending stiffness to airway elastance has been computed. In this study, we extend that work by including surface tension and intraluminal fluid in the model. With surface tension, the pressure on the inner surface of the elastic mucosa is modified by the pressure difference across the air-liquid interface. As folds form in the mucosa, intraluminal fluid collects in pools in the depressions formed by the folds, and the curvature of the air-liquid interface becomes nonuniform. If the amount of intraluminal fluid is small, < 2% of luminal volume, the pools of intraluminal fluid are small, the air-liquid interface nearly coincides with the surface of the mucosa, and the area of the air-liquid interface remains constant as airway cross-sectional area decreases. In that case, surface energy is independent of airway area, and surface tension has no effect on airway mechanics. If the amount of intraluminal fluid is > 2%, the area of the air-liquid interface decreases as airway cross-sectional area decreases. and surface tension contributes to airway compression. The model predicts that surface tension plus intraluminal fluid can cause an instability in the area-pressure curve of small airways. This instability provides a mechanism for abrupt airway closure and abrupt reopening at a higher opening pressure.

Encapsulated proppants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.

2018-01-30

A capsule for carrying a proppant for emplaced in a formation containing formation fluid by a hydraulic fracture operation using a fracturing fluid. The capsule includes a capsule body. The capsule body includes a proppant. There is a surface layer on the capsule body that is permeable to the formation fluid or the fracturing fluid or is permeable to both the formation fluid and the fracturing fluid. The proppant material is dry cement that interacts with the formation fluid or the fracturing fluid or both the formation fluid and the fracturing fluid that migrate through the surface layer and ismore » taken up by the dry cement causing the dry cement to harden.« less

Encapsulated proppants

DOEpatents

Aines, Roger D.; Bourcier, William L.; Duoss, Eric B.; Roberts, Jeffery James; Spadaccini, Christopher M.; Stolaroff, Joshuah K.

2018-01-09

A capsule for carrying a proppant for emplaced in a formation containing formation fluid by a hydraulic fracture operation using a fracturing fluid. The capsule includes a capsule body. The capsule body includes a proppant. There is a surface layer on the capsule body that is permeable to the formation fluid or the fracturing fluid or is permeable to both the formation fluid and the fracturing fluid. The proppant material is dry cement that interacts with the formation fluid or the fracturing fluid or both the formation fluid and the fracturing fluid that migrate through the surface layer and is taken up by the dry cement causing the dry cement to harden.

Fluid lubricated bearing construction

DOEpatents

Dunning, John R.; Boorse, Henry A.; Boeker, Gilbert F.

1976-01-01

1. A fluid lubricated thrust bearing assembly comprising, in combination, a first bearing member having a plain bearing surface, a second bearing member having a bearing surface confronting the bearing surface of said first bearing member and provided with at least one spiral groove extending inwardly from the periphery of said second bearing member, one of said bearing members having an axial fluid-tight well, a source of fluid lubricant adjacent to the periphery of said second bearing member, and means for relatively rotating said bearing members to cause said lubricant to be drawn through said groove and to flow between said bearing surfaces, whereby a sufficient pressure is built up between said bearing surfaces and in said well to tend to separate said bearing surfaces.

Droplet-Surface Impingement Dynamics for Intelligent Spray Design

NASA Technical Reports Server (NTRS)

Wal, Randy L. Vander; Kizito, John P.; Tryggvason, Gretar

2004-01-01

Spray cooling has high potential in thermal management and life support systems by overcoming the deleterious effect of microgravity upon two-phase heat transfer. In particular spray cooling offers several advantages in heat flux removal that include the following: 1) By maintaining a wetted surface, spray droplets impinge upon a thin fluid film rather than a dry solid surface; 2. Most heat transfer surfaces will not be smooth but rough. Roughness can enhance conductive cooling, aid liquid removal by flow channeling; and 3. Spray momentum can be used to a) substitute for gravity delivering fluid to the surface, b) prevent local dryout and potential thermal runaway and c) facilitate liquid and vapor removal. Yet high momentum results in high We and Re numbers characterizing the individual spray droplets. Beyond an impingement threshold, droplets splash rather than spread. Heat flux declines and spray cooling efficiency can markedly decrease. Accordingly we are investigating droplet impingement upon a) dry solid surfaces, b) fluid films, c) rough surfaces and determining splashing thresholds and relationships for both dry surfaces and those covered by fluid films. We are presently developing engineering correlations delineating the boundary between splashing and non-splashing regions. Determining the splash/non-splash boundary is important for many practical applications. Coating and cooling processes would each benefit from near-term empirical relations and subsequent models. Such demonstrations can guide theoretical development by providing definitive testing of its predictive capabilities. Thus, empirical relations describing the boundary between splash and non-splash are given for drops impinging upon a dry solid surface and upon a thin fluid film covering a similar surface. Analytical simplification of the power laws describing the boundary between the splash and non-splash regions yields insight into the engineering parameters governing the splash and non-splash outcomes of the fluid droplets. The power law correlation is shown separating the splashing versus non-splashing regions as developed for droplets impinging upon a dry solid surface. Splashing upon a dry surface is reasonably described by Ca greater than 0.85, reflecting the competing roles of surface tension and viscosity. The power law correlation is shown separating the splashing versus non-splashing regions as developed for droplets impinging upon a thin fluid film covering the solid surface. Splashing upon a thin fluid film, as described by v (pd/s) greater than 63, is governed by fluid density and surface tension, but is rather independent of viscosity. Finally, the data presented here suggests that a more direct dependence upon the surface tension and viscosity, given a better understanding of their interplay, would allow accurate description of the droplet-surface impacts for more complicated situations involving non-Newtonian fluids, specifically those exhibiting viscoelastic behavior.

Pressure Roller For Tape-Lift Tests

NASA Technical Reports Server (NTRS)

Abrams, Eve

1991-01-01

Rolling device applies nearly constant, uniform pressure to surface. Simple tool exerts nearly constant pressure via compression of sheath by fixed amount. Pins hold wheels on cylinder and cylinder on tangs of handle. Cylinder and handle made of metal or plastic. Sheath press-fit or glued to cylinder. End pins attached to cylinder by adhesive or screw threads. Device intended for use in taking tape-lift samples of particulate contamination on surface.

Applications of Modern Hydrodynamics to Aeronautics. Part 1: Fundamental Concepts and the Most Important Theorems. Part 2: Applications

NASA Technical Reports Server (NTRS)

Prandtl, L.

1979-01-01

A discussion of the principles of hydrodynamics of nonviscous fluids in the case of motion of solid bodies in a fluid is presented. Formulae are derived to demonstrate the transition from the fluid surface to a corresponding 'control surface'. The external forces are compounded of the fluid pressures on the control surface and the forces which are exercised on the fluid by any solid bodies which may be inside of the control surfaces. Illustrations of these formulae as applied to the acquisition of transformations from a known simple flow to new types of flow for other boundaries are given. Theoretical and experimental investigations of models of airship bodies are presented.

Vasospasm After Craniopharyngioma Surgery: Can We Prevent It?

PubMed

Singh, Apinderpreeet; Salunke, Pravin; Rangan, Vasundhara; Ahuja, Chirag K; Bhadada, Sanjay

2017-05-01

Vasospasm after craniopharyngioma surgery, although rare, has been reported. Hypotheses regarding possible causative factors, including major vessel handling during surgery and tumor cyst fluid spillage, do not explain vasospasm occurring in the late postoperative period. We have attempted to consider the probable pathogenic mechanisms of this complication and measures to prevent it. Of 60 patients operated for craniopharyngiomas over a period of 4 years, 6 who had clinical and radiologically demonstrable vasospasm were identified. Each case was analyzed retrospectively, and relevant variables were studied. Five of the 6 patients developed vasospasm in the second or third week after surgery. Only 2 of these patients had a favorable outcome. There was significant altered fluid balance during this period; however, patients remained misleadingly eunatremic. This most often coincided with the transition period from syndrome of inappropriate antidiuretic hormone to diabetes insipidus (DI) and the period after steroid taper to minimal dose. Major vessel handling during radical craniopharyngioma surgery is likely to predispose them to spasm, accentuated by rapid shifts of fluid and electrolytes during different phases of DI. This is further complicated by a relative hypocortisolic state caused by tendency to taper off steroids early. Hypocortisolism masks DI leading to dehydration and possibly vasospasm. Once vasospasm develops, it is not easy to reverse. Radiologic reversal with intra-arterial nimodipine may not translate into a good clinical response. Therefore, prudence lies in its prevention. Close monitoring of fluids and electrolytes with optimal steroid cover is necessary until stabilization of DI to prevent this complication. Copyright © 2017 Elsevier Inc. All rights reserved.

Near-Surface Wind Predictions in Complex Terrain with a CFD Approach Optimized for Atmospheric Boundary Layer Flows

NASA Astrophysics Data System (ADS)

Wagenbrenner, N. S.; Forthofer, J.; Butler, B.; Shannon, K.

2014-12-01

Near-surface wind predictions are important for a number of applications, including transport and dispersion, wind energy forecasting, and wildfire behavior. Researchers and forecasters would benefit from a wind model that could be readily applied to complex terrain for use in these various disciplines. Unfortunately, near-surface winds in complex terrain are not handled well by traditional modeling approaches. Numerical weather prediction models employ coarse horizontal resolutions which do not adequately resolve sub-grid terrain features important to the surface flow. Computational fluid dynamics (CFD) models are increasingly being applied to simulate atmospheric boundary layer (ABL) flows, especially in wind energy applications; however, the standard functionality provided in commercial CFD models is not suitable for ABL flows. Appropriate CFD modeling in the ABL requires modification of empirically-derived wall function parameters and boundary conditions to avoid erroneous streamwise gradients due to inconsistences between inlet profiles and specified boundary conditions. This work presents a new version of a near-surface wind model for complex terrain called WindNinja. The new version of WindNinja offers two options for flow simulations: 1) the native, fast-running mass-consistent method available in previous model versions and 2) a CFD approach based on the OpenFOAM modeling framework and optimized for ABL flows. The model is described and evaluations of predictions with surface wind data collected from two recent field campaigns in complex terrain are presented. A comparison of predictions from the native mass-consistent method and the new CFD method is also provided.

Surface cleanliness of fluid systems, specification for

NASA Technical Reports Server (NTRS)

1995-01-01

This specification establishes surface cleanliness levels, test methods, cleaning and packaging requirements, and protection and inspection procedures for determining surface cleanliness. These surfaces pertain to aerospace parts, components, assemblies, subsystems, and systems in contact with any fluid medium.

A finite difference method for a coupled model of wave propagation in poroelastic materials.

PubMed

Zhang, Yang; Song, Limin; Deffenbaugh, Max; Toksöz, M Nafi

2010-05-01

A computational method for time-domain multi-physics simulation of wave propagation in a poroelastic medium is presented. The medium is composed of an elastic matrix saturated with a Newtonian fluid, and the method operates on a digital representation of the medium where a distinct material phase and properties are specified at each volume cell. The dynamic response to an acoustic excitation is modeled mathematically with a coupled system of equations: elastic wave equation in the solid matrix and linearized Navier-Stokes equation in the fluid. Implementation of the solution is simplified by introducing a common numerical form for both solid and fluid cells and using a rotated-staggered-grid which allows stable solutions without explicitly handling the fluid-solid boundary conditions. A stability analysis is presented which can be used to select gridding and time step size as a function of material properties. The numerical results are shown to agree with the analytical solution for an idealized porous medium of periodically alternating solid and fluid layers.

Acoustically excited surface waves on empty or fluid-filled cylindrical and spherical shells

NASA Astrophysics Data System (ADS)

Ahyi, A. Claude; Cao, H.; Raju, P. K.; Werby, M. F.; Bao, X. L.; Überall, H.

2002-05-01

A comparative study is presented of the acoustical excitation of circumferential (surface) waves on fluid-immersed cylindrical or spherical metal shells, which may be either evacuated, or filled with the same or a different fluid. The excited surface waves can manifest themselves by the resonances apparent in the sound scattering amplitude, which they cause upon phase matching following repeated circumnavigations of the target object, or by their re-radiation into the external fluid in the manner of head waves. We plot dispersion curves versus frequency of the surface waves, which for evacuated shells have a generally rising character, while the fluid filling adds an additional set of circumferential waves that descend with frequency. The resonances of these latter waves may also be interpreted as being due to phase matching, but they may alternately be interpreted as constituting the eigenfrequencies of the internal fluid contained in an elastic enclosure.

Free-Surface Fluid-Object Interaction for the Large-Scale Computation of Ship Hydrodynamics Phenomena

DTIC Science & Technology

2014-05-21

simulating air-water free -surface flow, fluid-object interaction (FOI), and fluid-structure interaction (FSI) phenomena for complex geometries, and...with no limitations on the motion of the free surface, and with particular emphasis on ship hydrodynamics. The following specific research objectives...were identified for this project: 1) Development of a theoretical framework for free -surface flow, FOI and FSI that is a suitable starting point

Introduction to Generalized Functions with Applications in Aerodynamics and Aeroacoustics

NASA Technical Reports Server (NTRS)

Farassat, F.

1994-01-01

Generalized functions have many applications in science and engineering. One useful aspect is that discontinuous functions can be handled as easily as continuous or differentiable functions and provide a powerful tool in formulating and solving many problems of aerodynamics and acoustics. Furthermore, generalized function theory elucidates and unifies many ad hoc mathematical approaches used by engineers and scientists. We define generalized functions as continuous linear functionals on the space of infinitely differentiable functions with compact support, then introduce the concept of generalized differentiation. Generalized differentiation is the most important concept in generalized function theory and the applications we present utilize mainly this concept. First, some results of classical analysis, are derived with the generalized function theory. Other applications of the generalized function theory in aerodynamics discussed here are the derivations of general transport theorems for deriving governing equations of fluid mechanics, the interpretation of the finite part of divergent integrals, the derivation of the Oswatitsch integral equation of transonic flow, and the analysis of velocity field discontinuities as sources of vorticity. Applications in aeroacoustics include the derivation of the Kirchhoff formula for moving surfaces, the noise from moving surfaces, and shock noise source strength based on the Ffowcs Williams-Hawkings equation.

Autonomous selection of PDE inpainting techniques vs. exemplar inpainting techniques for void fill of high resolution digital surface models

NASA Astrophysics Data System (ADS)

Rahmes, Mark; Yates, J. Harlan; Allen, Josef DeVaughn; Kelley, Patrick

2007-04-01

High resolution Digital Surface Models (DSMs) may contain voids (missing data) due to the data collection process used to obtain the DSM, inclement weather conditions, low returns, system errors/malfunctions for various collection platforms, and other factors. DSM voids are also created during bare earth processing where culture and vegetation features have been extracted. The Harris LiteSite TM Toolkit handles these void regions in DSMs via two novel techniques. We use both partial differential equations (PDEs) and exemplar based inpainting techniques to accurately fill voids. The PDE technique has its origin in fluid dynamics and heat equations (a particular subset of partial differential equations). The exemplar technique has its origin in texture analysis and image processing. Each technique is optimally suited for different input conditions. The PDE technique works better where the area to be void filled does not have disproportionately high frequency data in the neighborhood of the boundary of the void. Conversely, the exemplar based technique is better suited for high frequency areas. Both are autonomous with respect to detecting and repairing void regions. We describe a cohesive autonomous solution that dynamically selects the best technique as each void is being repaired.

Mixed variational formulations of finite element analysis of elastoacoustic/slosh fluid-structure interaction

NASA Technical Reports Server (NTRS)

Felippa, Carlos A.; Ohayon, Roger

1991-01-01

A general three-field variational principle is obtained for the motion of an acoustic fluid enclosed in a rigid or flexible container by the method of canonical decomposition applied to a modified form of the wave equation in the displacement potential. The general principle is specialized to a mixed two-field principle that contains the fluid displacement potential and pressure as independent fields. This principle contains a free parameter alpha. Semidiscrete finite-element equations of motion based on this principle are displayed and applied to the transient response and free-vibrations of the coupled fluid-structure problem. It is shown that a particular setting of alpha yields a rich set of formulations that can be customized to fit physical and computational requirements. The variational principle is then extended to handle slosh motions in a uniform gravity field, and used to derive semidiscrete equations of motion that account for such effects.

The Role of Flight Experiments in the Development of Cryogenic Fluid Management Technologies

NASA Technical Reports Server (NTRS)

Chato, David J.

2006-01-01

This paper reviews the history of cryogenic fluid management technology development and infusion into both the Saturn and Centaur vehicles. Ground testing and analysis proved inadequate to demonstrate full scale performance. As a consequence flight demonstration with a full scale vehicle was required by both the Saturn and Centaur programs to build confidence that problems were addressed. However; the flight vehicles were highly limited on flight instrumentation and the flight demonstration locked-in the design without challenging the function of design elements. Projects reviewed include: the Aerobee Sounding Rocket Cryogenic Fluid Management (CFM) tests which served as a valuable stepping stone to flight demonstration and built confidence in the ability to handle hydrogen in low gravity; the Saturn IVB Fluid Management Qualification flight test; the Atlas Centaur demonstration flights to develop two burn capability; and finally the Titan Centaur two post mission flight tests.

Wafer bonded epitaxial templates for silicon heterostructures

DOEpatents

Atwater, Jr., Harry A.; Zahler, James M [Pasadena, CA; Morral, Anna Fontcubera I [Paris, FR

2008-03-11

A heterostructure device layer is epitaxially grown on a virtual substrate, such as an InP/InGaAs/InP double heterostructure. A device substrate and a handle substrate form the virtual substrate. The device substrate is bonded to the handle substrate and is composed of a material suitable for fabrication of optoelectronic devices. The handle substrate is composed of a material suitable for providing mechanical support. The mechanical strength of the device and handle substrates is improved and the device substrate is thinned to leave a single-crystal film on the virtual substrate such as by exfoliation of a device film from the device substrate. An upper portion of the device film exfoliated from the device substrate is removed to provide a smoother and less defect prone surface for an optoelectronic device. A heterostructure is epitaxially grown on the smoothed surface in which an optoelectronic device may be fabricated.

Wafer bonded epitaxial templates for silicon heterostructures

NASA Technical Reports Server (NTRS)

Atwater, Harry A., Jr. (Inventor); Zahler, James M. (Inventor); Morral, Anna Fontcubera I (Inventor)

2008-01-01

A heterostructure device layer is epitaxially grown on a virtual substrate, such as an InP/InGaAs/InP double heterostructure. A device substrate and a handle substrate form the virtual substrate. The device substrate is bonded to the handle substrate and is composed of a material suitable for fabrication of optoelectronic devices. The handle substrate is composed of a material suitable for providing mechanical support. The mechanical strength of the device and handle substrates is improved and the device substrate is thinned to leave a single-crystal film on the virtual substrate such as by exfoliation of a device film from the device substrate. An upper portion of the device film exfoliated from the device substrate is removed to provide a smoother and less defect prone surface for an optoelectronic device. A heterostructure is epitaxially grown on the smoothed surface in which an optoelectronic device may be fabricated.

Morphology-Patterned Anisotropic Wetting Surface for Fluid Control and Gas-Liquid Separation in Microfluidics.

PubMed

Wang, Shuli; Yu, Nianzuo; Wang, Tieqiang; Ge, Peng; Ye, Shunsheng; Xue, Peihong; Liu, Wendong; Shen, Huaizhong; Zhang, Junhu; Yang, Bai

2016-05-25

This article shows morphology-patterned stripes as a new platform for directing flow guidance of the fluid in microfluidic devices. Anisotropic (even unidirectional) spreading behavior due to anisotropic wetting of the underlying surface is observed after integrating morphology-patterned stripes with a Y-shaped microchannel. The anisotropic wetting flow of the fluid is influenced by the applied pressure, dimensions of the patterns, including the period and depth of the structure, and size of the channels. Fluids with different surface tensions show different flowing anisotropy in our microdevice. Moreover, the morphology-patterned surfaces could be used as a microvalve, and gas-water separation in the microchannel was realized using the unidirectional flow of water. Therefore, benefiting from their good performance and simple fabrication process, morphology-patterned surfaces are good candidates to be applied in controlling the fluid behavior in microfluidics.

Magnetically Actuated Propellant Orientation Experiment, Controlling Fluid Motion With Magnetic Fields in a Low-Gravity Environment

NASA Technical Reports Server (NTRS)

Martin, J. J.; Holt, J. B.

2000-01-01

This report details the results of a series of fluid motion experiments to investigate the use of magnets to orient fluids in a low-gravity environment. The fluid of interest for this project was liquid oxygen (LO2) since it exhibits a paramagnetic behavior (is attracted to magnetic fields). However, due to safety and handling concerns, a water-based ferromagnetic mixture (produced by Ferrofluidics Corporation) was selected to simplify procedures. Three ferromagnetic fluid mixture strengths and a nonmagnetic water baseline were tested using three different initial fluid positions with respect to the magnet. Experiment accelerometer data were used with a modified computational fluid dynamics code termed CFX-4 (by AEA Technologies) to predict fluid motion. These predictions compared favorably with experiment video data, verifying the code's ability to predict fluid motion with and without magnetic influences. Additional predictions were generated for LO2 with the same test conditions and geometries used in the testing. Test hardware consisted of a cylindrical Plexiglas tank (6-in. bore with 10-in. length), a 6,000-G rare Earth magnet (10-in. ring), three-axis accelerometer package, and a video recorder system. All tests were conducted aboard the NASA Reduced-Gravity Workshop, a KC-135A aircraft.

Working Fluids for Increasing Capacities of Heat Pipes

NASA Technical Reports Server (NTRS)

Chao, David F.; Zhang, Nengli

2004-01-01

A theoretical and experimental investigation has shown that the capacities of heat pipes can be increased through suitable reformulation of their working fluids. The surface tensions of all of the working fluids heretofore used in heat pipes decrease with temperature. As explained in more detail below, the limits on the performance of a heat pipe are associated with the decrease in the surface tension of the working fluid with temperature, and so one can enhance performance by reformulating the working fluid so that its surface tension increases with temperature. This improvement is applicable to almost any kind of heat pipe in almost any environment. The heat-transfer capacity of a heat pipe in its normal operating-temperature range is subject to a capillary limit and a boiling limit. Both of these limits are associated with the temperature dependence of surface tension of the working fluid. In the case of a traditional working fluid, the decrease in surface tension with temperature causes a body of the liquid phase of the working fluid to move toward a region of lower temperature, thus preventing the desired spreading of the liquid in the heated portion of the heat pipe. As a result, the available capillary-pressure pumping head decreases as the temperature of the evaporator end of the heat pipe increases, and operation becomes unstable. Water has widely been used as a working fluid in heat pipes. Because the surface tension of water decreases with increasing temperature, the heat loads and other aspects of performance of heat pipes that contain water are limited. Dilute aqueous solutions of long-chain alcohols have shown promise as substitutes for water that can offer improved performance, because these solutions exhibit unusual surface-tension characteristics: Experiments have shown that in the cases of an aqueous solution of an alcohol, the molecules of which contain chains of more than four carbon atoms, the surface tension increases with temperature when the temperature exceeds a certain value. There are also other liquids that have surface tensions that increase with temperature and could be used as working fluids in heat pipes. For example, as a substitute for ammonia, which is the working fluid in some heat pipes, one could use a solution of ammonia and an ionic surfactant.

Micromachined force-balance feedback accelerometer with optical displacement detection

DOEpatents

Nielson, Gregory N.; Langlois, Eric; Baker, Michael; Okandan, Murat; Anderson, Robert

2014-07-22

An accelerometer includes a proof mass and a frame that are formed in a handle layer of a silicon-on-an-insulator (SOI). The proof mass is separated from the frame by a back-side trench that defines a boundary of the proof mass. The accelerometer also includes a reflector coupled to a top surface of the proof mass. An optical detector is located above the reflector at the device side. The accelerometer further includes at least one suspension spring. The suspension spring has a handle anchor that extends downwards from the device side to the handle layer to mechanically support upward and downward movement of the proof mass relative to a top surface of the proof mass.

The Sample Handling System for the Mars Icebreaker Life Mission: from Dirt to Data

NASA Technical Reports Server (NTRS)

Dave, Arwen; Thompson, Sarah J.; McKay, Christopher P.; Stoker, Carol R.; Zacny, Kris; Paulsen, Gale; Mellerowicz, Bolek; Glass, Brian J.; Wilson, David; Bonaccorsi, Rosalba;

Manufacture, distribution, and handling of nitrate salts for solar-thermal applications

NASA Astrophysics Data System (ADS)

Fiorucci, L. C.; Goldstein, S. L.

1982-11-01

The low cost and attractive physical properties of molten sodium/potassium nitrate salts were shown to be one of the most cost effective fluids for heat absorption and thermal energy storage in Solar Central Receiver (SCR) systems. Information related to the availability, transport, handling, and utilization of these salts for commercial size SCR applications is provided. The following items are reviewed: existing manufacturing processes for natural and synthetic nitrates; the upstream availability of raw materials; downstream existing and projected demand for these products in other sectors of the economy; and relevant handling and distribution technologies. Safety considerations and issues more directly related to the SCR facility, such as initial system charging, salt maintenance and regeneration, and disposal are also reviewed. Options for supply, surge storage, and initial charging are discussed for the 1 MWt to 300 MWe range of solar plant sizes.

A density functional theory for association of fluid molecules with a functionalized surface: fluid-wall single and double bonding.

PubMed

Haghmoradi, Amin; Wang, Le; Chapman, Walter G

2017-02-01

In this manuscript we extend Wertheim's two-density formalism beyond its first order to model a system of fluid molecules with a single association site close to a planar hard wall with association sites on its surface in a density functional theory framework. The association sites of the fluid molecules are small enough that they can form only one bond, while the wall association sites are large enough to bond with more than one fluid molecule. The effects of temperature and of bulk fluid and wall site densities on the fluid density profile, extent of association, and competition between single and double bonding of fluid segments at the wall sites versus distance from the wall are presented. The theory predictions are compared with new Monte Carlo simulation results and they are in good agreement. The theory captures the surface coverage over wide ranges of temperature and bulk density by introducing the effect of steric hindrance in fluid association at a wall site.

Viscoelastic drops moving on hydrophilic and superhydrophobic surfaces.

PubMed

Xu, H; Clarke, A; Rothstein, J P; Poole, R J

2018-03-01

So-called "superhydrophobic" surfaces are strongly non-wetting such that fluid droplets very easily roll off when the surface is tilted. Our interest here is in understanding if this is also true, all else held equal, for viscoelastic fluid drops. We study the movement of Newtonian and well-characterised constant-viscosity elastic liquids when various surfaces, including hydrophilic (smooth glass), weakly hydrophobic (embossed polycarbonate) and superhydrophobic surfaces (embossed PTFE), are impulsively tilted. Digital imaging is used to record the motion and extract drop velocity. Optical and SEM imaging is used to probe the surfaces. In comparison with "equivalent" Newtonian fluids (same viscosity, density surface tension and contact angles), profound differences for the elastic fluids are only observed on the superhydrophobic surfaces: the elastic drops slide at a significantly reduced rate and complex branch-like patterns are left on the surface by the drop's wake including, on various scales, beads-on-a-string-like phenomena. The strong viscoelastic effect is caused by stretching filaments of fluid from isolated islands, residing at pinning sites on the surface pillars, of order ∼30 µm in size. On this scale, the local strain rates are sufficient to extend the polymer chains, locally increasing the extensional viscosity of the solution, retarding the drop. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Fluid assisted installation of electrical cable accessories

DOEpatents

Mayer, Robert W.; Silva, Frank A.

1977-01-01

An electrical cable accessory includes a generally tubular member of elastomeric material which is to be installed by placement over a cylindrical surface to grip the cylindrical surface, when in appropriate assembled relation therewith, with a predetermined gripping force established by dilation of the tubular member, the installation being facilitated by introducing fluid under pressure, through means provided in the tubular member, between the tubular member and the cylindrical surface, and simultaneously impeding the escape of the fluid under pressure from between the tubular member and the cylindrical surface by means adjacent one of the ends of the tubular member to cause dilation of the tubular member and establish a fluid layer between the tubular member and the cylindrical surface, thereby reducing the gripping force during installation.

Hierarchial parallel computer architecture defined by computational multidisciplinary mechanics

NASA Technical Reports Server (NTRS)

Padovan, Joe; Gute, Doug; Johnson, Keith

1989-01-01

The goal is to develop an architecture for parallel processors enabling optimal handling of multi-disciplinary computation of fluid-solid simulations employing finite element and difference schemes. The goals, philosphical and modeling directions, static and dynamic poly trees, example problems, interpolative reduction, the impact on solvers are shown in viewgraph form.

The Magnetic Reconnection Code: an AMR-based fully implicit simulation suite

NASA Astrophysics Data System (ADS)

Germaschewski, K.; Bhattacharjee, A.; Ng, C.-S.

2006-12-01

Extended MHD models, which incorporate two-fluid effects, are promising candidates to enhance understanding of collisionless reconnection phenomena in laboratory, space and astrophysical plasma physics. In this paper, we introduce two simulation codes in the Magnetic Reconnection Code suite which integrate reduced and full extended MHD models. Numerical integration of these models comes with two challenges: Small-scale spatial structures, e.g. thin current sheets, develop and must be well resolved by the code. Adaptive mesh refinement (AMR) is employed to provide high resolution where needed while maintaining good performance. Secondly, the two-fluid effects in extended MHD give rise to dispersive waves, which lead to a very stringent CFL condition for explicit codes, while reconnection happens on a much slower time scale. We use a fully implicit Crank--Nicholson time stepping algorithm. Since no efficient preconditioners are available for our system of equations, we instead use a direct solver to handle the inner linear solves. This requires us to actually compute the Jacobian matrix, which is handled by a code generator that calculates the derivative symbolically and then outputs code to calculate it.

Quartz ball valve

NASA Technical Reports Server (NTRS)

Goetz, C.; Ingle, W. M. (Inventor)

1980-01-01

A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports.

[Pseudomigraine with pleocytosis].

PubMed

Pariso, Gabriela S; Parisi, Virginia L; Persi, Gabriel G; Canto, Lucila; Rugilo, Carlos A; Gatto, Emilia M

2006-01-01

The syndrome of transient headache and neurological deficits with cerebrospinal fluid lymphocytosis or pseudomigraine with temporary neurological symptoms and lymphocytic pleocytosis (HaNDL) is a syndrome consisting of recurrent headaches, reversible neurological deficit, lymphocytic pleocytosis in cerebrospinal fluid (CSF), variable duration over time and spontaneous resolution. Although several etiopathogenic mechanisms have been suggested (vascular, infectous, immunological and calcium channelopthy), its etiology remains unknown. We describe a 28 year old female, with recurrent migraine with pleocytosis, confusional syndrome and transient neurological deficit. The clinical remission was achieved within two months. Although its etiology remains unknown the differential diagnosis is discussed in order to keep in mind this syndrome.

White blood cell counting system

NASA Technical Reports Server (NTRS)

1972-01-01

The design, fabrication, and tests of a prototype white blood cell counting system for use in the Skylab IMSS are presented. The counting system consists of a sample collection subsystem, sample dilution and fluid containment subsystem, and a cell counter. Preliminary test results show the sample collection and the dilution subsystems are functional and fulfill design goals. Results for the fluid containment subsystem show the handling bags cause counting errors due to: (1) adsorption of cells to the walls of the container, and (2) inadequate cleaning of the plastic bag material before fabrication. It was recommended that another bag material be selected.

A Modular, Reusable Latch and Decking System for Securing Payloads During Launch and Planetary Surface Transport

NASA Technical Reports Server (NTRS)

Doggett, William R.; Dorsey, John T.; Jones, Thomas C.; King, Bruce D.; Mikulas, Martin M.

2011-01-01

Efficient handling of payloads destined for a planetary surface, such as the moon or mars, requires robust systems to secure the payloads during transport on the ground, in space and on the planetary surface. In addition, mechanisms to release the payloads need to be reliable to ensure successful transfer from one vehicle to another. An efficient payload handling strategy must also consider the devices available to support payload handling. Cranes used for overhead lifting are common to all phases of payload handling on Earth. Similarly, both recent and past studies have demonstrated that devices with comparable functionality will be needed to support lunar outpost operations. A first generation test-bed of a new high performance device that provides the capabilities of both a crane and a robotic manipulator, the Lunar Surface Manipulation System (LSMS), has been designed, built and field tested and is available for use in evaluating a system to secure payloads to transportation vehicles. A payload handling approach must address all phases of payload management including: ground transportation, launch, planetary transfer and installation in the final system. In addition, storage may be required during any phase of operations. Each of these phases requires the payload to be lifted and secured to a vehicle, transported, released and lifted in preparation for the next transportation or storage phase. A critical component of a successful payload handling approach is a latch and associated carrier system. The latch and carrier system should minimize requirements on the: payload, carrier support structure and payload handling devices as well as be able to accommodate a wide range of payload sizes. In addition, the latch should; be small and lightweight, support a method to apply preload, be reusable, integrate into a minimal set of hard-points and have manual interfaces to actuate the latch should a problem occur. A latching system which meets these requirements has been designed and fabricated and will be described in detail. This latching system works in conjunction with a payload handling device such as the LSMS, and the LSMS has been used to test first generation latch and carrier hardware. All tests have been successful during the first phase of operational evaluations. Plans for future tests of first generation latch and carrier hardware with the LSMS are also described.

A Modular, Reusable Latch and Decking System for Securing Payloads During Launch and Planetary Surface Transport

NASA Technical Reports Server (NTRS)

Doggett, William R.; Dorsey, John T.; Jones, Thomas C.; King, Bruce D.; Mikulas, Martin M.

2010-01-01

Efficient handling of payloads destined for a planetary surface, such as the moon or Mars, requires robust systems to secure the payloads during transport on the ground, in-space and on the planetary surface. In addition, mechanisms to release the payloads need to be reliable to ensure successful transfer from one vehicle to another. An efficient payload handling strategy must also consider the devices available to support payload handling. Cranes used for overhead lifting are common to all phases of payload handling on Earth. Similarly, both recent and past studies have demonstrated that devices with comparable functionality will be needed to support lunar outpost operations. A first generation test-bed of a new high performance device that provides the capabilities of both a crane and a robotic manipulator, the Lunar Surface Manipulation System (LSMS), has been designed, built and field tested and is available for use in evaluating a system to secure payloads to transportation vehicles. National Institute of Aerospace, Hampton Va 23662 A payload handling approach must address all phases of payload management including: ground transportation, launch, planetary transfer and installation in the final system. In addition, storage may be required during any phase of operations. Each of these phases requires the payload to be lifted and secured to a vehicle, transported, released and lifted in preparation for the next transportation or storage phase. A critical component of a successful payload handling approach is a latch and associated carrier system. The latch and carrier system should minimize requirements on the: payload, carrier support structure and payload handling devices as well as be able to accommodate a wide range of payload sizes. In addition, the latch should; be small and lightweight, support a method to apply preload, be reusable, integrate into a minimal set of hard-points and have manual interfaces to actuate the latch should a problem occur. A latching system which meets these requirements has been designed and fabricated and will be described in detail. This latching system works in conjunction with a payload handling device such as the LSMS, and the LSMS has been used to test first generation latch and carrier hardware. All tests have been successful during the first phase of operational evaluations. Plans for future tests of first generation latch and carrier hardware with the LSMS are also described.

Nucleate Boiling Heat Transfer Studied Under Reduced-Gravity Conditions

NASA Technical Reports Server (NTRS)

Chao, David F.; Hasan, Mohammad M.

2000-01-01

Boiling is known to be a very efficient mode of heat transfer, and as such, it is employed in component cooling and in various energy-conversion systems. In space, boiling heat transfer may be used in thermal management, fluid handling and control, power systems, and on-orbit storage and supply systems for cryogenic propellants and life-support fluids. Recent interest in the exploration of Mars and other planets and in the concept of in situ resource utilization on the Martian and Lunar surfaces highlights the need to understand how gravity levels varying from the Earth's gravity to microgravity (1g = or > g/g(sub e) = or > 10(exp -6)g) affect boiling heat transfer. Because of the complex nature of the boiling process, no generalized prediction or procedure has been developed to describe the boiling heat transfer coefficient, particularly at reduced gravity levels. Recently, Professor Vijay K. Dhir of the University of California at Los Angeles proposed a novel building-block approach to investigate the boiling phenomena in low-gravity to microgravity environments. This approach experimentally investigates the complete process of bubble inception, growth, and departure for single bubbles formed at a well-defined and controllable nucleation site. Principal investigator Professor Vijay K. Dhir, with support from researchers from the NASA Glenn Research Center at Lewis Field, is performing a series of pool boiling experiments in the low-gravity environments of the KC 135 microgravity aircraft s parabolic flight to investigate the inception, growth, departure, and merger of bubbles from single- and multiple-nucleation sites as a function of the wall superheat and the liquid subcooling. Silicon wafers with single and multiple cavities of known characteristics are being used as test surfaces. Water and PF5060 (an inert liquid) were chosen as test liquids so that the role of surface wettability and the magnitude of the effect of interfacial tension on boiling in reduced gravity can be investigated.

Effect of Spreading Time on Contact Angle of Nanofluid on the Surface of Stainless Steel AISI 316 and Zircalloy 4

NASA Astrophysics Data System (ADS)

Prajitno, D. H.; Trisnawan, V.; Syarif, D. G.

2017-05-01

The solid surface tension plays an important role in the heat and mass transfer system for heat exchanger equipment. In the nuclear power plant industry, the stainless steel AISI 316 and Zircalloy 4 have been used for long time as structure materials. The purpose of the experimental is to study solid state surface tension behavior by measure contact angle Nano fluid contain nano particle alumina on metal surface of stainless steel AISI 316 and Zircalloy 4 by sessile drop method. The experiment is to measure the static contact angle and drop nano fluid contains nano particle alumina on stainless steel 316 and zircalloy 4 with different spreading time from 1 to 30 minute. It was observed that stainless steel 316 and zircalloy 4 lose their hydrophobic properties with increasing elapsed time during drop of nano fluid on the surface of alloy. As a result the contact angle of nano fluid on surface of metal is decrease with increasing elapsed time. While the magnitude diameter of drop nano fluid and wetting surface is increase with increasing elapsed time on the surface of the stainless steel SS 316 and Zircalloy 4.

Surface tension of dilute alcohol-aqueous binary fluids: n-Butanol/water, n-Pentanol/water, and n-Hexanol/water solutions

NASA Astrophysics Data System (ADS)

Cheng, Kuok Kong; Park, Chanwoo

2017-07-01

Surface tension of pure fluids, inherently decreasing with regard to temperature, creates a thermo-capillary-driven (Marangoni) flow moving away from a hot surface. It has been known that few high-carbon alcohol-aqueous solutions exhibit an opposite behavior of the surface tension increasing with regard to temperature, such that the Marangoni flow moves towards the hot surface (self-rewetting effect). We report the surface tensions of three dilute aqueous solutions of n-Butanol, n-Pentanol and n-Hexanol as self-rewetting fluids measured for ranges of alcohol concentration (within solubility limits) and fluid temperatures (25-85 °C). A maximum bubble pressure method using a leak-tight setup was used to measure the surface tension without evaporation losses of volatile components. It was found from this study that the aqueous solutions with higher-carbon alcohols exhibit a weak self-rewetting behavior, such that the surface tensions remain constant or slightly increases above about 60 °C. These results greatly differ from the previously reported results showing a strong self-rewetting behavior, which is attributed to the measurement errors associated with the evaporation losses of test fluids during open-system experiments.

Fluid cooled electrical assembly

DOEpatents

Rinehart, Lawrence E.; Romero, Guillermo L.

2007-02-06

A heat producing, fluid cooled assembly that includes a housing made of liquid-impermeable material, which defines a fluid inlet and a fluid outlet and an opening. Also included is an electrical package having a set of semiconductor electrical devices supported on a substrate and the second major surface is a heat sink adapted to express heat generated from the electrical apparatus and wherein the second major surface defines a rim that is fit to the opening. Further, the housing is constructed so that as fluid travels from the fluid inlet to the fluid outlet it is constrained to flow past the opening thereby placing the fluid in contact with the heat sink.

Generating a Simulated Fluid Flow over a Surface Using Anisotropic Diffusion

NASA Technical Reports Server (NTRS)

Rodriguez, David L. (Inventor); Sturdza, Peter (Inventor)

2016-01-01

A fluid-flow simulation over a computer-generated surface is generated using a diffusion technique. The surface is comprised of a surface mesh of polygons. A boundary-layer fluid property is obtained for a subset of the polygons of the surface mesh. A gradient vector is determined for a selected polygon, the selected polygon belonging to the surface mesh but not one of the subset of polygons. A maximum and minimum diffusion rate is determined along directions determined using the gradient vector corresponding to the selected polygon. A diffusion-path vector is defined between a point in the selected polygon and a neighboring point in a neighboring polygon. An updated fluid property is determined for the selected polygon using a variable diffusion rate, the variable diffusion rate based on the minimum diffusion rate, maximum diffusion rate, and the gradient vector.

Study on Controls of Fluids in Nanochannel via Hybrid Surface

NASA Astrophysics Data System (ADS)

Ye, Ziran

This thesis contributes to the investigation of controls of nanofluidic fluids by utilizing hybrid surface patterns in nanochannel. Nanofluidics is a core and interdisciplinary research field which manipulates, controls and analyzes fluids in nanoscale and develop potential bio/chemical applications. This thesis studies the surface-induced phenomena in nanofluidics, we use surface decoration on nanochannel walls to investigate the influences on fluid motion and further explore the fundamental physical principle of this behavior. To begin with, we designed and fabricated the nanofluidic mixer for the first time, which comprised hybrid surface patterns with different wettabilities on both top and bottom walls of nanochannel. Although microfluidic mixers have been intensively investigated, nanofluidic mixer has never been reported. Without any inside geometric structure of nanochannel, the mixing phenomenon can be achieved by the surface patterns and the mixing length can be significantly shortened comparing with micromixer. We attribute this achievement to the chaotic flows of two fluids induced by the patterned surface. The surface-related phenomena may not be so prominent on large scale, however, it is pronounced when the scale shrinks down to nanometer due to the large surface-to-volume ratio in nanochannel. In the second part of this work, based on the technology of nanofabrication and similar principle, we built up another novel method to control the speed of capillary flow in nanochannel in a quantitative manner. Surface patterns were fabricated on the nanochannel walls to slow down the capillary flow. The flow speed can be precisely controlled by modifying hydrophobicity ratio. Under the extreme surface-to-volume ratio in nanochannel, the significant surface effect on the fluid effectively reduced the speed of capillary flow without any external energy source and equipment. Such approach may be adopted for a wide variety of nanofluidicsbased biochemical analysis systems.

Global Design Optimization for Aerodynamics and Rocket Propulsion Components

NASA Technical Reports Server (NTRS)

Shyy, Wei; Papila, Nilay; Vaidyanathan, Rajkumar; Tucker, Kevin; Turner, James E. (Technical Monitor)

2000-01-01

Modern computational and experimental tools for aerodynamics and propulsion applications have matured to a stage where they can provide substantial insight into engineering processes involving fluid flows, and can be fruitfully utilized to help improve the design of practical devices. In particular, rapid and continuous development in aerospace engineering demands that new design concepts be regularly proposed to meet goals for increased performance, robustness and safety while concurrently decreasing cost. To date, the majority of the effort in design optimization of fluid dynamics has relied on gradient-based search algorithms. Global optimization methods can utilize the information collected from various sources and by different tools. These methods offer multi-criterion optimization, handle the existence of multiple design points and trade-offs via insight into the entire design space, can easily perform tasks in parallel, and are often effective in filtering the noise intrinsic to numerical and experimental data. However, a successful application of the global optimization method needs to address issues related to data requirements with an increase in the number of design variables, and methods for predicting the model performance. In this article, we review recent progress made in establishing suitable global optimization techniques employing neural network and polynomial-based response surface methodologies. Issues addressed include techniques for construction of the response surface, design of experiment techniques for supplying information in an economical manner, optimization procedures and multi-level techniques, and assessment of relative performance between polynomials and neural networks. Examples drawn from wing aerodynamics, turbulent diffuser flows, gas-gas injectors, and supersonic turbines are employed to help demonstrate the issues involved in an engineering design context. Both the usefulness of the existing knowledge to aid current design practices and the need for future research are identified.

Damping effects of magnetic fluids of various saturation magnetization (abstract)

NASA Astrophysics Data System (ADS)

Chagnon, Mark

1990-05-01

Magnetic fluids have been widely accepted for use in loudspeaker voice coil gaps as viscous dampers and liquid coolants. When applied properly to a voice coil in manufacturing of the loudspeaker, dramatic improvement in frequency response and power handling is observed. Over the past decade, a great deal of study has been given to the effects of damping as a function of fluid viscosity. It is known that the apparent viscosity of a magnetic fluid increases as a function of applied magnetic field, and that the viscosity versus field relationship approximate that of the magnetization versus applied field. At applied magnetic field strength sufficient to cause magnetic saturation of the fluid, no further increase in viscosity with increased magnetic field is observed. In order to provide a better understanding of the second order magnetoviscous damping effects in magnetic fluids used in voice coils and to provide a better loudspeaker design criterion using magnetic fluids, we have studied the effect on damping of several magnetic fluids of the same O field viscosity and of varying saturation magnetization. Magnetic fluids with saturation magnetization ranging from 50 to 450 G and 100 cps viscosity at O applied field were injected into the voice coil gap of a standard midrange loudspeaker. The frequency response over the entire dynamic range of the speaker was measured. The changes in frequency response versus fluid magnetization are reported.

Simulated molecular-scale interaction of supercritical fluid mobile and stationary phases.

PubMed

Siders, Paul D

2017-12-08

In supercritical fluid chromatography, molecules from the mobile phase adsorb on the stationary phase. Stationary-phase alkylsilane-terminated silica surfaces might adsorb molecules at the silica, among the silanes, on a silane layer, or in pore space between surfaces. Mobile phases of carbon dioxide, pure and modified with methanol, and stationary phases were simulated at the molecular scale. Classical atomistic force fields were used in Gibbs-ensemble hybrid Monte Carlo calculations. Excess adsorption of pure carbon dioxide mobile phase peaked at fluid densities of 0.002-0.003Å -3 . Mobile phase adsorption from 7% methanol in carbon dioxide peaked at lower fluid density. Methanol was preferentially adsorbed from the mixed fluid. Surface silanes prevented direct interaction of fluid-phase molecules with silica. Some adsorbed molecules mixed with tails of bonded silanes; some formed layers above the silanes. Much adsorption occurred by filling the space between surfaces in the stationary-phase model. The distribution in the stationary phase of methanol molecules from a modified fluid phase varied with pressure. Copyright © 2017 Elsevier B.V. All rights reserved.

Manipulation of fluids in three-dimensional porous photonic structures with patterned surface properties

DOEpatents

Aizenberg, Joanna; Burgess, Ian B.; Mishchenko, Lidiya; Hatton, Benjamin; Loncar, Marko

2016-03-08

A three-dimensional porous photonic structure, whose internal pore surfaces can be provided with desired surface properties in a spatially selective manner with arbitrary patterns, and methods for making the same are described. When exposed to a fluid (e.g., via immersion or wicking), the fluid can selectively penetrate the regions of the structure with compatible surface properties. Broad applications, for example in security, encryption and document authentication, as well as in areas such as simple microfluidics and diagnostics, are anticipated.

Manipulation of fluids in three-dimensional porous photonic structures with patterned surface properties

DOEpatents

Aizenberg, Joanna; Burgess, Ian; Mishchenko, Lidiya; Hatton, Benjamin; Loncar, Marko

2017-12-26

A three-dimensional porous photonic structure, whose internal pore surfaces can be provided with desired surface properties in a spatially selective manner with arbitrary patterns, and methods for making the same are described. When exposed to a fluid (e.g., via immersion or wicking), the fluid can selectively penetrate the regions of the structure with compatible surface properties. Broad applications, for example in security, encryption and document authentication, as well as in areas such as simple microfluidics and diagnostics, are anticipated.

Generalized Boussinesq-Scriven surface fluid model with curvature dissipation for liquid surfaces and membranes.

PubMed

Aguilar Gutierrez, Oscar F; Herrera Valencia, Edtson E; Rey, Alejandro D

2017-10-01

Curvature dissipation is relevant in synthetic and biological processes, from fluctuations in semi-flexible polymer solutions, to buckling of liquid columns, tomembrane cell wall functioning. We present a micromechanical model of curvature dissipation relevant to fluid membranes and liquid surfaces based on a parallel surface parameterization and a stress constitutive equation appropriate for anisotropic fluids and fluid membranes.The derived model, aimed at high curvature and high rate of change of curvature in liquid surfaces and membranes, introduces additional viscous modes not included in the widely used 2D Boussinesq-Scriven rheological constitutive equation for surface fluids.The kinematic tensors that emerge from theparallel surface parameterization are the interfacial rate of deformation and the surface co-rotational Zaremba-Jaumann derivative of the curvature, which are used to classify all possibledissipative planar and non-planar modes. The curvature dissipation function that accounts for bending, torsion and twist rates is derived and analyzed under several constraints, including the important inextensional bending mode.A representative application of the curvature dissipation model to the periodic oscillation in nano-wrinkled outer hair cells show how and why curvature dissipation decreases with frequency, and why the 100kHz frequency range is selected. These results contribute to characterize curvature dissipation in membranes and liquid surfaces. Copyright © 2017 Elsevier Inc. All rights reserved.

Coupling MHD and PIC models in 2 dimensions

NASA Astrophysics Data System (ADS)

Daldorff, L.; Toth, G.; Sokolov, I.; Gombosi, T. I.; Lapenta, G.; Brackbill, J. U.; Markidis, S.; Amaya, J.

2013-12-01

Even for extended fluid plasma models, like Hall, anisotropic ion pressure and multi fluid MHD, there are still many plasma phenomena that are not well captured. For this reason, we have coupled the Implicit Particle-In-Cell (iPIC3D) code with the BATSRUS global MHD code. The PIC solver is applied in a part of the computational domain, for example, in the vicinity of reconnection sites, and overwrites the MHD solution. On the other hand, the fluid solver provides the boundary conditions for the PIC code. To demonstrate the use of the coupled codes for magnetospheric applications, we perform a 2D magnetosphere simulation, where BATSRUS solves for Hall MHD in the whole domain except for the tail reconnection region, which is handled by iPIC3D.

Harmonic oscillations of laminae in non-Newtonian fluids: A lattice Boltzmann-Immersed Boundary approach

NASA Astrophysics Data System (ADS)

De Rosis, Alessandro

2014-11-01

In this paper, the fluid dynamics induced by a rigid lamina undergoing harmonic oscillations in a non-Newtonian calm fluid is investigated. The fluid is modelled through the lattice Boltzmann method and the flow is assumed to be nearly incompressible. An iterative viscosity-correction based procedure is proposed to properly account for the non-Newtonian fluid feature and its accuracy is evaluated. In order to handle the mutual interaction between the lamina and the encompassing fluid, the Immersed Boundary method is adopted. A numerical campaign is performed. In particular, the effect of the non-Newtonian feature is highlighted by investigating the fluid forces acting on a harmonically oscillating lamina for different values of the Reynolds number. The findings prove that the non-Newtonian feature can drastically influence the behaviour of the fluid and, as a consequence, the forces acting upon the lamina. Several considerations are carried out on the time history of the drag coefficient and the results are used to compute the added mass through the hydrodynamic function. Moreover, the computational cost involved in the numerical simulations is discussed. Finally, two applications concerning water resources are investigated: the flow through an obstructed channel and the particle sedimentation. Present findings highlight a strong coupling between the body shape, the Reynolds number, and the flow behaviour index.

Kuipers during replacement of the Marangoni Surface Fluid Dynamics Experiment

NASA Image and Video Library

2012-03-15

ISS030-E-142827 (15 March 2012) --- European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, works to remove the Marangoni Surface fluid physics experiment from the Fluid Physics Experiment Facility (FPEF) in the Kibo laboratory of the International Space Station.

Relativistic elasticity of stationary fluid branes

NASA Astrophysics Data System (ADS)

Armas, Jay; Obers, Niels A.

2013-02-01

Fluid mechanics can be formulated on dynamical surfaces of arbitrary codimension embedded in a background space-time. This has been the main object of study of the blackfold approach in which the emphasis has primarily been on stationary fluid configurations. Motivated by this approach we show under certain conditions that a given stationary fluid configuration living on a dynamical surface of vanishing thickness and satisfying locally the first law of thermodynamics will behave like an elastic brane when the surface is subject to small deformations. These results, which are independent of the number of space-time dimensions and of the fluid arising from a gravitational dual, reveal the (electro)elastic character of (charged) black branes when considering extrinsic perturbations.

Behavior of fluids in a weightless environment

NASA Technical Reports Server (NTRS)

Fester, D. A.; Eberhardt, R. N.; Tegart, J. R.

1977-01-01

Fluid behavior in a low-g environment is controlled primarily by surface tension forces. Certain fluid and system characteristics determine the magnitude of these forces for both a free liquid surface and liquid in contact with a solid. These characteristics, including surface tension, wettability or contact angle, system geometry, and the relationships governing their interaction, are discussed. Various aspects of fluid behavior in a low-g environment are then presented. This includes the formation of static interface shapes, oscillation and rotation of drops, coalescence, the formation of foams, tendency for cavitation, and diffusion in liquids which were observed during the Skylab fluid mechanics science demonstrations. Liquid reorientation and capillary pumping to establish equilibrium configurations for various system geometries, observed during various free-fall (drop-tower) low-g tests, are also presented. Several passive low-g fluid storage and transfer systems are discussed. These systems use surface tension forces to control the liquid/vapor interface and provide gas-free liquid transfer and liquid-free vapor venting.

Numerical Modelling of Three-Fluid Flow Using The Level-set Method

NASA Astrophysics Data System (ADS)

Li, Hongying; Lou, Jing; Shang, Zhi

2014-11-01

This work presents a numerical model for simulation of three-fluid flow involving two different moving interfaces. These interfaces are captured using the level-set method via two different level-set functions. A combined formulation with only one set of conservation equations for the whole physical domain, consisting of the three different immiscible fluids, is employed. Numerical solution is performed on a fixed mesh using the finite volume method. Surface tension effect is incorporated using the Continuum Surface Force model. Validation of the present model is made against available results for stratified flow and rising bubble in a container with a free surface. Applications of the present model are demonstrated by a variety of three-fluid flow systems including (1) three-fluid stratified flow, (2) two-fluid stratified flow carrying the third fluid in the form of drops and (3) simultaneous rising and settling of two drops in a stationary third fluid. The work is supported by a Thematic and Strategic Research from A*STAR, Singapore (Ref. #: 1021640075).

A binomial modeling approach for upscaling colloid transport under unfavorable conditions: Emergent prediction of extended tailing

NASA Astrophysics Data System (ADS)

Hilpert, Markus; Rasmuson, Anna; Johnson, William P.

2017-07-01

Colloid transport in saturated porous media is significantly influenced by colloidal interactions with grain surfaces. Near-surface fluid domain colloids experience relatively low fluid drag and relatively strong colloidal forces that slow their downgradient translation relative to colloids in bulk fluid. Near-surface fluid domain colloids may reenter into the bulk fluid via diffusion (nanoparticles) or expulsion at rear flow stagnation zones, they may immobilize (attach) via primary minimum interactions, or they may move along a grain-to-grain contact to the near-surface fluid domain of an adjacent grain. We introduce a simple model that accounts for all possible permutations of mass transfer within a dual pore and grain network. The primary phenomena thereby represented in the model are mass transfer of colloids between the bulk and near-surface fluid domains and immobilization. Colloid movement is described by a Markov chain, i.e., a sequence of trials in a 1-D network of unit cells, which contain a pore and a grain. Using combinatorial analysis, which utilizes the binomial coefficient, we derive the residence time distribution, i.e., an inventory of the discrete colloid travel times through the network and of their probabilities to occur. To parameterize the network model, we performed mechanistic pore-scale simulations in a single unit cell that determined the likelihoods and timescales associated with the above colloid mass transfer processes. We found that intergrain transport of colloids in the near-surface fluid domain can cause extended tailing, which has traditionally been attributed to hydrodynamic dispersion emanating from flow tortuosity of solute trajectories.

Aseptic Handling of the MOMA Mass Spectrometer After Dry Heat Microbial Reduction

NASA Technical Reports Server (NTRS)

Lalime, Erin

2017-01-01

Mars Organic Molecule Analyzer Mass Spectrometer (MOMA-MS) is an instrument in the larger MOMA instrument suite for the European Space Agency (ESA) ExoMars 2020 Rover. As a life-detection instrument on a Mars landing mission, MOMA-MS has very stringent Planetary Protection (PP) bioburden requirements. Within the MOMA instrument suite, the hardware surfaces of the sample path must be cleaned to a level of 0.03 spore/sq m. To meet this requirement, a process called Dry Heat Microbial Reduction (DHMR) is used to decrease the number of viable spores by 4 orders of magnitude. Before DHMR, the hardware is handled using standard cleanroom practices, while after DHMR, all sample path surfaces must be handled aseptically when exposed. Aseptic handling of the sample path involves a number of strategies and protocols including working only in an aseptic ISO class 5 work space, limiting the amount of time of exposure, using sterile garmenting with sterile gloves, and using sterile tools. Before work begins, the aseptic workspace will be tested for bioburden and particle fallout, and all tools that will contact sample path surfaces must be sterilized. During the exposure activity, sterile garments will be worn, sterile tools will be handled in a 2 person set up so that the operator touches only the sterile tool and not the exterior surfaces of the sterile pouch, and the environment will be monitored with active and passive fallout for bioburden and particle levels. Any breach in the planetary protection cleanliness can necessitate repeating DHMR, which not only has significant cost and schedule implications, it also become a risk to hardware that is not rated for repeated long exposures to high temperatures.

Sample handling in surface sensitive chemical and biological sensing: a practical review of basic fluidics and analyte transport.

PubMed

Orgovan, Norbert; Patko, Daniel; Hos, Csaba; Kurunczi, Sándor; Szabó, Bálint; Ramsden, Jeremy J; Horvath, Robert

2014-09-01

This paper gives an overview of the advantages and associated caveats of the most common sample handling methods in surface-sensitive chemical and biological sensing. We summarize the basic theoretical and practical considerations one faces when designing and assembling the fluidic part of the sensor devices. The influence of analyte size, the use of closed and flow-through cuvettes, the importance of flow rate, tubing length and diameter, bubble traps, pressure-driven pumping, cuvette dead volumes, and sample injection systems are all discussed. Typical application areas of particular arrangements are also highlighted, such as the monitoring of cellular adhesion, biomolecule adsorption-desorption and ligand-receptor affinity binding. Our work is a practical review in the sense that for every sample handling arrangement considered we present our own experimental data and critically review our experience with the given arrangement. In the experimental part we focus on sample handling in optical waveguide lightmode spectroscopy (OWLS) measurements, but the present study is equally applicable for other biosensing technologies in which an analyte in solution is captured at a surface and its presence is monitored. Explicit attention is given to features that are expected to play an increasingly decisive role in determining the reliability of (bio)chemical sensing measurements, such as analyte transport to the sensor surface; the distorting influence of dead volumes in the fluidic system; and the appropriate sample handling of cell suspensions (e.g. their quasi-simultaneous deposition). At the appropriate places, biological aspects closely related to fluidics (e.g. cellular mechanotransduction, competitive adsorption, blood flow in veins) are also discussed, particularly with regard to their models used in biosensing. Copyright © 2014 Elsevier B.V. All rights reserved.

Multi-Fluid Moment Simulations of Ganymede using the Next-Generation OpenGGCM

NASA Astrophysics Data System (ADS)

Wang, L.; Germaschewski, K.; Hakim, A.; Bhattacharjee, A.; Raeder, J.

2015-12-01

We coupled the multi-fluid moment code Gkeyll[1,2] to the next-generation OpenGGCM[3], and studied the reconnection dynamics at the Ganymede. This work is part of our effort to tackle the grand challenge of integrating kinetic effects into global fluid models. The multi-fluid moment model integrates kinetic effects in that it can capture crucial kinetic physics like pressure tensor effects by evolving moments of the Vlasov equations for each species. This approach has advantages over previous models: desired kinetic effects, together with other important effects like the Hall effect, are self-consistently embedded in the moment equations, and can be efficiently implemented, while not suffering from severe time-step restriction due to plasma oscillation nor artificial whistler modes. This model also handles multiple ion species naturally, which opens up opportunties in investigating the role of oxygen in magnetospheric reconnection and improved coupling to ionosphere models. In this work, the multi-fluid moment solver in Gkeyll was wrapped as a time-stepping module for the high performance, highly flexible next-generation OpenGGCM. Gkeyll is only used to provide the local plasma solver, while computational aspects like parallelization and boundary conditions are handled entirely by OpenGGCM, including interfacing to other models like ionospheric boundary conditions provided by coupling with CTIM [3]. The coupled code is used to study the dynamics near Ganymede, and the results are compared with MHD and Hall MHD results by Dorelli et al. [4]. Hakim, A. (2008). Journal of Fusion Energy, 27, 36-43. Hakim, A., Loverich, J., & Shumlak, U. (2006). Journal of Computational Physics, 219, 418-442. Raeder, J., Larson, D., Li, W., Kepko, E. L., & Fuller-Rowell, T. (2008). Space Science Reviews, 141(1-4), 535-555. Dorelli, J. C., Glocer, A., Collinson, G., & Tóth, G. (2015). Journal of Geophysical Research: Space Physics, 120.

Adsorption losses from urine-based cannabinoid calibrators during routine use.

PubMed

Blanc, J A; Manneh, V A; Ernst, R; Berger, D E; de Keczer, S A; Chase, C; Centofanti, J M; DeLizza, A J

1993-08-01

The major metabolite of cannabis found in urine, 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid (delta 9-THC), is the compound most often used to calibrate cannabinoid immunoassays. The hydrophobic delta 9-THC molecule is known to adsorb to solid surfaces. This loss of analyte from calibrator solutions can lead to inaccuracy in the analytical system. Because the calibrators remain stable when not used, analyte loss is most probably caused by handling techniques. In an effort to develop an effective means of overcoming adsorption losses, we quantified cannabinoid loss from calibrators during the testing process. In studying handling of these solutions, we found noticeable, significant losses attributable to both the kind of pipette used for transfer and the contact surface-to-volume ratio of calibrator solution in the analyzer cup. Losses were quantified by immunoassay and by radioactive tracer. We suggest handling techniques that can minimize adsorption of delta 9-THC to surfaces. Using the appropriate pipette and maintaining a minimum surface-to-volume ratio in the analyzer cup effectively reduces analyte loss.

Generating a Simulated Fluid Flow Over an Aircraft Surface Using Anisotropic Diffusion

NASA Technical Reports Server (NTRS)

Rodriguez, David L. (Inventor); Sturdza, Peter (Inventor)

2013-01-01

A fluid-flow simulation over a computer-generated aircraft surface is generated using a diffusion technique. The surface is comprised of a surface mesh of polygons. A boundary-layer fluid property is obtained for a subset of the polygons of the surface mesh. A pressure-gradient vector is determined for a selected polygon, the selected polygon belonging to the surface mesh but not one of the subset of polygons. A maximum and minimum diffusion rate is determined along directions determined using a pressure gradient vector corresponding to the selected polygon. A diffusion-path vector is defined between a point in the selected polygon and a neighboring point in a neighboring polygon. An updated fluid property is determined for the selected polygon using a variable diffusion rate, the variable diffusion rate based on the minimum diffusion rate, maximum diffusion rate, and angular difference between the diffusion-path vector and the pressure-gradient vector.

Tribology Experiment in Zero Gravity

NASA Technical Reports Server (NTRS)

Pan, C. H. T.; Gause, R. L.; Whitaker, A. F.; Finckenor, M. M.

2015-01-01

A tribology experiment in zero gravity was performed during the orbital flight of Spacelab 1 to study the motion of liquid lubricants over solid surfaces. The absence of a significant gravitational force facilitates observation of such motions as controlled by interfacial and capillary forces. Two experimental configurations were used. One deals with the liquid on one solid surface, and the other with the liquid between a pair of closed spaced surfaces. Time sequence photographs of fluid motion on a solid surface yielded spreading rate data of several fluid-surface combinations. In general, a slow spreading process as governed by the tertiary junction can be distinguished from a more rapid process which is driven by surface tension controlled internal fluid pressure. Photographs were also taken through the transparent bushings of several experimental journal bearings. Morphology of incomplete fluid films and its fluctuation with time suggest the presence or absence of unsteady phenomena of the bearing-rotor system in various arrangements.

Permian paleoclimate data from fluid inclusions in halite

USGS Publications Warehouse

Benison, K.C.; Goldstein, R.H.

1999-01-01

This study has yielded surface water paleotemperatures from primary fluid inclusions in mid Permian Nippewalla Group halite from western Kansas. A 'cooling nucleation' method is used to generate vapor bubbles in originally all-liquid primary inclusions. Then, surface water paleotemperatures are obtained by measuring temperatures of homogenization to liquid. Homogenization temperatures ranged from 21??C to 50??C and are consistent along individual fluid inclusion assemblages, indicating that the fluid inclusions have not been altered by thermal reequilibration. Homogenization temperatures show a range of up to 26??C from base to top of individual cloudy chevron growth bands. Petrographic and fluid inclusion evidence indicate that no significant pressure correction is needed for the homogenization temperature data. We interpret these homogenization temperatures to represent shallow surface water paleotemperatures. The range in temperatures from base to top of single chevron bands may reflect daily temperatures variations. These Permian surface water temperatures fall within the same range as some modern evaporative surface waters, suggesting that this Permian environment may have been relatively similar to its modern counterparts. Shallow surface water temperatures in evaporative settings correspond closely to local air temperatures. Therefore, the Permian surface water temperatures determined in this study may be considered proxies for local Permian air temperatures.

An immersed boundary method for two-phase fluids and gels and the swimming of Caenorhabditis elegans through viscoelastic fluids

PubMed Central

Lee, Pilhwa; Wolgemuth, Charles W.

2016-01-01

The swimming of microorganisms typically involves the undulation or rotation of thin, filamentary objects in a fluid or other medium. Swimming in Newtonian fluids has been examined extensively, and only recently have investigations into microorganism swimming through non-Newtonian fluids and gels been explored. The equations that govern these more complex media are often nonlinear and require computational algorithms to study moderate to large amplitude motions of the swimmer. Here, we develop an immersed boundary method for handling fluid-structure interactions in a general two-phase medium, where one phase is a Newtonian fluid and the other phase is viscoelastic (e.g., a polymer melt or network). We use this algorithm to investigate the swimming of an undulating, filamentary swimmer in 2D (i.e., a sheet). A novel aspect of our method is that it allows one to specify how forces produced by the swimmer are distributed between the two phases of the fluid. The algorithm is validated by comparing theoretical predictions for small amplitude swimming in gels and viscoelastic fluids. We show how the swimming velocity depends on material parameters of the fluid and the interaction between the fluid and swimmer. In addition, we simulate the swimming of Caenorhabditis elegans in viscoelastic fluids and find good agreement between the swimming speeds and fluid flows in our simulations and previous experimental measurements. These results suggest that our methodology provides an accurate means for exploring the physics of swimming through non-Newtonian fluids and gels. PMID:26858520

A new technique for surface and shallow subsurface paleobarometry using fluid inclusions: An example from the Upper Ordovician Viola Formation, Kansas, USA

USGS Publications Warehouse

Newell, K.D.; Goldstein, R.H.

1999-01-01

This research illustrates a new approach for paleobarometry employing heterogeneously entrapped fluid inclusions to determine timing and depth of diagenesis. Heterogeneously entrapped fluid inclusions (gas + water) in vug-filling quartz from the Upper Ordovician Viola Formation in the Midcontinent of the United States were analyzed for their internal pressure with a fluid-inclusion crushing stage. The free gas in fluid inclusions was entrapped at near-surface temperature, as indicated by the presence of all-liquid fluid inclusions and fluid inclusions with low homogenization temperatures ( <40??C). Crushing the crystal and measuring the change in bubble size determines the pressure of entrapment directly. Heterogeneous trapping is indicated by widely varying L:V ratios, from all-liquid to vapor-rich. Gas bubbles in most fluid inclusions analyzed expanded upon release to atmospheric pressure, but some collapsed. A mode of 1.5 to 2.0 atm internal pressure was indicated by the crushing runs, but pressures up to 42.9 atm were recorded. Quartz precipitation and associated fluid-inclusion entrapment therefore occurred over a wide depth-range, but principally at depths of approximately 10 m. Crushing runs done in kerosene confirmed the presence of hydrocarbon gases in most of these inclusions, and bulk analyses of gases in the quartz by quadrupole mass spectrometer revealed methane, ethane, and atmospheric gases. The hydrocarbon gases may have originated in deeper thermogenically mature sedimentary strata, and then leaked to the near-surface where they were entrapped in the precipitating quartz cement. Freezing data indicate an event of quartz precipitation from fluids of marine-fresh water intermediate salinity and other events of precipitation from more saline fluids. Considering the determined pressures, the precipitating fluids probably originated at surfaces of subaerial exposure (unconformities) and surfaces of evaporite precipitation in the overlying Silurian strata. Thus, saline inclusions most likely originated from sinking of saline surface waters during Silurian time. Lower-salinity fluids record fluxes of meteoric water during development of unconformities in the Silurian. This type of paleobarometric study may have application in many other sedimentary systems, provided low-temperature and heterogeneous entrapment of an immiscible gas phase can be demonstrated for the fluid-inclusion assemblages studied.

21 CFR 660.45 - Labeling.

Code of Federal Regulations, 2012 CFR

2012-04-01

... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.45 Labeling. In... capable of transmitting hepatitis and should be handled accordingly. (d) The package shall include a... test methods, and (3) warnings as to possible hazards, including hepatitis transmitted in handling the...

21 CFR 660.45 - Labeling.

Code of Federal Regulations, 2014 CFR

2014-04-01

... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.45 Labeling. In... capable of transmitting hepatitis and should be handled accordingly. (d) The package shall include a... test methods, and (3) warnings as to possible hazards, including hepatitis transmitted in handling the...

21 CFR 660.45 - Labeling.

Code of Federal Regulations, 2013 CFR

2013-04-01

... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.45 Labeling. In... capable of transmitting hepatitis and should be handled accordingly. (d) The package shall include a... test methods, and (3) warnings as to possible hazards, including hepatitis transmitted in handling the...

21 CFR 660.45 - Labeling.

Code of Federal Regulations, 2011 CFR

2011-04-01

... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.45 Labeling. In... capable of transmitting hepatitis and should be handled accordingly. (d) The package shall include a... test methods, and (3) warnings as to possible hazards, including hepatitis transmitted in handling the...

21 CFR 660.45 - Labeling.

Code of Federal Regulations, 2010 CFR

2010-04-01

... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.45 Labeling. In... capable of transmitting hepatitis and should be handled accordingly. (d) The package shall include a... test methods, and (3) warnings as to possible hazards, including hepatitis transmitted in handling the...

Drag penalty due to the asperities in the substrate of super-hydrophobic and liquid infused surfaces

NASA Astrophysics Data System (ADS)

Garcia Cartagena, Edgardo J.; Arenas, Isnardo; Leonardi, Stefano

2017-11-01

Direct numerical simulations of two superposed fluids in a turbulent channel with a textured surface made of pinnacles of random height have been performed. The viscosity ratio between the two fluids are N =μo /μi = 50 (μo and μi are the viscosities of outer and inner fluid respectively) mimicking a super-hydrophobic surface (water over air) and N=2.5 (water over heptane) resembling a liquid infused surface. Two set of simulations have been performed varying the Reynolds number, Reτ = 180 and Reτ = 390 . The interface between the two fluids is flat simulating infinite surface tension. The position of the interface between the two fluids has been varied in the vertical direction from the base of the substrate (what would be a rough wall) to the highest point of the roughness. Drag reduction is very sensitive to the position of the interface between the two fluids. Asperities above the interface induce a large form drag and diminish considerably the drag reduction. When the mean height of the surface measured from the interface in the outer fluid is greater than one wall unit, k+ > 1 , the drag increases with respect to a smooth wall. Present results provide a guideline to the accuracy required in manufacturing super-hydrophobic and liquid infused surfaces. This work was supported under ONR MURI Grants N00014-12-0875 and N00014-12- 1-0962, Program Manager Dr. Ki-Han Kim. Numerical simulations were performed on the Texas Advanced Computer Center.

Valves and other mechanical components and equipment: A compilation

NASA Technical Reports Server (NTRS)

1976-01-01

The articles in this Compilation will be of interest to mechanical engineers, users and designers of machinery, and to those engineers and manufacturers specializing in fluid handling systems. Section 1 describes a number of valves and valve systems. Section 2 contains articles on machinery and mechanical devices that may have applications in a number of different areas.

A Better Method for Filling Pasteur Pipet Chromatography Columns

ERIC Educational Resources Information Center

Ruekberg, Ben

2006-01-01

An alternative method for the preparation of Pasteur pipet chromatography columns is presented that allows the column to be filled with solvent without bubbles and allows greater control of fluid flow while the materials to be separated are added. Students are required to wear gloves and goggles and caution should be used while handling glass…

Physics-based animation of large-scale splashing liquids, elastoplastic solids, and model-reduced flow

NASA Astrophysics Data System (ADS)

Gerszewski, Daniel James

Physical simulation has become an essential tool in computer animation. As the use of visual effects increases, the need for simulating real-world materials increases. In this dissertation, we consider three problems in physics-based animation: large-scale splashing liquids, elastoplastic material simulation, and dimensionality reduction techniques for fluid simulation. Fluid simulation has been one of the greatest successes of physics-based animation, generating hundreds of research papers and a great many special effects over the last fifteen years. However, the animation of large-scale, splashing liquids remains challenging. We show that a novel combination of unilateral incompressibility, mass-full FLIP, and blurred boundaries is extremely well-suited to the animation of large-scale, violent, splashing liquids. Materials that incorporate both plastic and elastic deformations, also referred to as elastioplastic materials, are frequently encountered in everyday life. Methods for animating such common real-world materials are useful for effects practitioners and have been successfully employed in films. We describe a point-based method for animating elastoplastic materials. Our primary contribution is a simple method for computing the deformation gradient for each particle in the simulation. Given the deformation gradient, we can apply arbitrary constitutive models and compute the resulting elastic forces. Our method has two primary advantages: we do not store or compare to an initial rest configuration and we work directly with the deformation gradient. The first advantage avoids poor numerical conditioning and the second naturally leads to a multiplicative model of deformation appropriate for finite deformations. One of the most significant drawbacks of physics-based animation is that ever-higher fidelity leads to an explosion in the number of degrees of freedom. This problem leads us to the consideration of dimensionality reduction techniques. We present several enhancements to model-reduced fluid simulation that allow improved simulation bases and two-way solid-fluid coupling. Specifically, we present a basis enrichment scheme that allows us to combine data-driven or artistically derived bases with more general analytic bases derived from Laplacian Eigenfunctions. Additionally, we handle two-way solid-fluid coupling in a time-splitting fashion---we alternately timestep the fluid and rigid body simulators, while taking into account the effects of the fluid on the rigid bodies and vice versa. We employ the vortex panel method to handle solid-fluid coupling and use dynamic pressure to compute the effect of the fluid on rigid bodies. Taken together, these contributions have advanced the state-of-the art in physics-based animation and are practical enough to be used in production pipelines.

Experimental and numerical CHT-investigations of cooling structures formed by lost cores in cast housings for optimal heat transfer

NASA Astrophysics Data System (ADS)

Kohlstädt, S.; Vynnycky, M.; Gebauer-Teichmann, A.

2018-05-01

This paper investigates the cooling performance of six different lost core designs for automotive cast houses with regard to their cooling efficiency. For this purpose, the conjugate heat transfer (CHT) solver, chtMultiregion, of the freely available CFD-toolbox OpenFOAM in its implementation of version 2.3.1 is used. The turbulence contribution to the Navier-Stokes equations is accounted for by using the RANS Menter SST k - ω model. The results are validated for one of the geometries by comparing with experimental data. Of the six investigated cooling structures, the one that forces the fluid flow to change its direction the most produces the lowest temperatures on the surface of the cast housing. This good cooling performance comes at the price of the highest pressure loss in the cooling fluid and hence increased pump power. It is also found that the relationship between performance and pressure drop is by no means generally linear. Slight changes in the design can lead to a structure which cools almost as well, but at much decreased pressure loss. Regarding the absolute values, the simulations showed that the designed cooling structures are suitable for handling the cooling requirements in the particular applications and that the maximum temperature stays below the critical limits of the electronic components.

Towards building a robust computational framework to simulate multi-physics problems - a solution technique for three-phase (gas-liquid-solid) interactions

NASA Astrophysics Data System (ADS)

Zhang, Lucy

In this talk, we show a robust numerical framework to model and simulate gas-liquid-solid three-phase flows. The overall algorithm adopts a non-boundary-fitted approach that avoids frequent mesh-updating procedures by defining independent meshes and explicit interfacial points to represent each phase. In this framework, we couple the immersed finite element method (IFEM) and the connectivity-free front tracking (CFFT) method that model fluid-solid and gas-liquid interactions, respectively, for the three-phase models. The CFFT is used here to simulate gas-liquid multi-fluid flows that uses explicit interfacial points to represent the gas-liquid interface and for its easy handling of interface topology changes. Instead of defining different levels simultaneously as used in level sets, an indicator function naturally couples the two methods together to represent and track each of the three phases. Several 2-D and 3-D testing cases are performed to demonstrate the robustness and capability of the coupled numerical framework in dealing with complex three-phase problems, in particular free surfaces interacting with deformable solids. The solution technique offers accuracy and stability, which provides a means to simulate various engineering applications. The author would like to acknowledge the supports from NIH/DHHS R01-2R01DC005642-10A1 and the National Natural Science Foundation of China (NSFC) 11550110185.

A moving control volume method for smooth computation of hydrodynamic forces and torques on immersed bodies

NASA Astrophysics Data System (ADS)

Nangia, Nishant; Patankar, Neelesh A.; Bhalla, Amneet P. S.

2017-11-01

Fictitious domain methods for simulating fluid-structure interaction (FSI) have been gaining popularity in the past few decades because of their robustness in handling arbitrarily moving bodies. Often the transient net hydrodynamic forces and torques on the body are desired quantities for these types of simulations. In past studies using immersed boundary (IB) methods, force measurements are contaminated with spurious oscillations due to evaluation of possibly discontinuous spatial velocity of pressure gradients within or on the surface of the body. Based on an application of the Reynolds transport theorem, we present a moving control volume (CV) approach to computing the net forces and torques on a moving body immersed in a fluid. The approach is shown to be accurate for a wide array of FSI problems, including flow past stationary and moving objects, Stokes flow, and high Reynolds number free-swimming. The approach only requires far-field (smooth) velocity and pressure information, thereby suppressing spurious force oscillations and eliminating the need for any filtering. The proposed moving CV method is not limited to a specific IB method and is straightforward to implement within an existing parallel FSI simulation software. This work is supported by NSF (Award Numbers SI2-SSI-1450374, SI2-SSI-1450327, and DGE-1324585), the US Department of Energy, Office of Science, ASCR (Award Number DE-AC02-05CH11231), and NIH (Award Number HL117163).

Challenging dyke ascent models using novel laboratory experiments: Implications for reinterpreting evidence of magma ascent and volcanism

NASA Astrophysics Data System (ADS)

Kavanagh, Janine L.; Burns, Alec J.; Hilmi Hazim, Suraya; Wood, Elliot P.; Martin, Simon A.; Hignett, Sam; Dennis, David J. C.

2018-04-01

Volcanic eruptions are fed by plumbing systems that transport magma from its source to the surface, mostly fed by dykes. Here we present laboratory experiments that model dyke ascent to eruption using a tank filled with a crust analogue (gelatine, which is transparent and elastic) that is injected from below by a magma analogue (dyed water). This novel experimental setup allows, for the first time, the simultaneous measurement of fluid flow, sub-surface and surface deformation during dyke ascent. During injection, a penny-shaped fluid-filled crack is formed, intrudes, and traverses the gelatine slab vertically to then erupt at the surface. Polarised light shows the internal stress evolution as the dyke ascends, and an overhead laser scanner measures the surface elevation change in the lead-up to dyke eruption. Fluorescent passive-tracer particles that are illuminated by a laser sheet are monitored, and the intruding fluid's flow dynamics and gelatine's sub-surface strain evolution is measured using particle image velocimetry and digital image correlation, respectively. We identify 4 previously undescribed stages of dyke ascent. Stage 1, early dyke growth: the initial dyke grows from the source, and two fluid jets circulate as the penny-shaped crack is formed. Stage 2, pseudo-steady dyke growth: characterised by the development of a rapidly uprising, central, single pseudo-steady fluid jet, as the dyke grows equally in length and width, and the fluid down-wells at the dyke margin. Sub-surface host strain is localised at the head region and the tail of the dyke is largely static. Stage 3, pre-eruption unsteady dyke growth: an instability in the fluid flow appears as the central fluid jet meanders, the dyke tip accelerates towards the surface and the tail thins. Surface deformation is only detected in the immediate lead-up to eruption and is characterised by an overall topographic increase, with axis-symmetric topographic highs developed above the dyke tip. Stage 4 is the onset of eruption, when fluid flow is projected outwards and focused towards the erupting fissure as the dyke closes. A simultaneous and abrupt decrease in sub-surface strain occurs as the fluid pressure is released. Our results provide a comprehensive physical framework upon which to interpret evidence of dyke ascent in nature, and suggest dyke ascent models need to be re-evaluated to account for coupled intrusive and extrusive processes and improve the recognition of monitoring signals that lead to volcanic eruptions in nature.

Multilevel fluidic flow control in a rotationally-driven polyester film microdevice created using laser print, cut and laminate.

PubMed

Ouyang, Yiwen; Li, Jingyi; Phaneuf, Christopher; Riehl, Paul S; Forest, Craig; Begley, Matthew; Haverstick, Doris M; Landers, James P

2016-01-21

This paper presents a simple and cost-effective polyester toner microchip fabricated with laser print and cut lithography (PCL) to use with a battery-powered centrifugal platform for fluid handling. The combination of the PCL microfluidic disc and centrifugal platform: (1) allows parallel aliquoting of two different reagents of four different volumes ranging from nL to μL with an accuracy comparable to a piston-driven air pipette; (2) incorporates a reciprocating mixing unit driven by a surface-tension pump for further dilution of reagents, and (3) is amenable to larger scale integration of assay multiplexing (including all valves and mixers) without substantially increasing fabrication cost and time. For a proof of principle, a 10 min colorimetric assay for the quantitation of the protein level in the human blood plasma samples is demonstrated on chip with a limit of detection of ∼5 mg mL(-1) and coefficient of variance of ∼7%.

Pneumatic System for Concentration of Micrometer-Size Lunar Soil

NASA Technical Reports Server (NTRS)

McKay, David; Cooper, Bonnie

2012-01-01

A report describes a size-sorting method to separate and concentrate micrometer- size dust from a broad size range of particles without using sieves, fluids, or other processes that may modify the composition or the surface properties of the dust. The system consists of four processing units connected in series by tubing. Samples of dry particulates such as lunar soil are introduced into the first unit, a fluidized bed. The flow of introduced nitrogen fluidizes the particulates and preferentially moves the finer grain sizes on to the next unit, a flat plate impactor, followed by a cyclone separator, followed by a Nuclepore polycarbonate filter to collect the dust. By varying the gas flow rate and the sizes of various orifices in the system, the size of the final and intermediate particles can be varied to provide the desired products. The dust can be collected from the filter. In addition, electron microscope grids can be placed on the Nuclepore filter for direct sampling followed by electron microscope characterization of the dust without further handling.

Dynamic analysis of ultrasonically levitated droplet with moving particle semi-implicit and distributed point source method

NASA Astrophysics Data System (ADS)

Wada, Yuji; Yuge, Kohei; Nakamura, Ryohei; Tanaka, Hiroki; Nakamura, Kentaro

2015-07-01

Numerical analysis of an ultrasonically levitated droplet with a free surface boundary is discussed. The droplet is known to change its shape from sphere to spheroid when it is suspended in a standing wave owing to the acoustic radiation force. However, few studies on numerical simulation have been reported in association with this phenomenon including fluid dynamics inside the droplet. In this paper, coupled analysis using the distributed point source method (DPSM) and the moving particle semi-implicit (MPS) method, both of which do not require grids or meshes to handle the moving boundary with ease, is suggested. A droplet levitated in a plane standing wave field between a piston-vibrating ultrasonic transducer and a reflector is simulated with the DPSM-MPS coupled method. The dynamic change in the spheroidal shape of the droplet is successfully reproduced numerically, and the gravitational center and the change in the spheroidal aspect ratio are discussed and compared with the previous literature.

Super Clean, Super Safe

NASA Technical Reports Server (NTRS)

2002-01-01

The Supersonic Gas/Liquid Cleaning System (SS-GLCS) has applications ranging from cleaning circuit boards to scouring building exteriors. The system does not abrade the surface of the hardware being cleaned, and it requires much lower levels of pressure while using very little water. An alternative to CFC-based solvents, the system mixes air and water from separate pressurized tanks, ejecting the gas- liquid mixture at supersonic speeds from a series of nozzles at the end of a hand-held wand. The water droplets have the kinetic energy to forcibly remove the contaminant material. The system leaves very little fluid that must be handled as contaminated waste. It can be applied in the aerospace, automotive, and medical industries, as well as to circuit boards, electronics, machinery, metals, plastics, and optics. With a nozzle that can be oriented in any direction, the system is adjustable to allow all sides of a part to be cleaned without reorientation. It requires minimal training and is easily moved on built-in casters

Electronic Publishing or Electronic Information Handling?

NASA Astrophysics Data System (ADS)

Heck, A.

The current dramatic evolution in information technology is bringing major modifications in the way scientists communicate. The concept of 'electronic publishing' is too restrictive and has often different, sometimes conflicting, interpretations. It is thus giving way to the broader notion of 'electronic information handling' encompassing the diverse types of information, the different media, as well as the various communication methodologies and technologies. New problems and challenges result also from this new information culture, especially on legal, ethical, and educational grounds. The procedures for validating 'published material' and for evaluating scientific activities will have to be adjusted too. 'Fluid' information is becoming a common concept. Electronic publishing cannot be conceived without link to knowledge bases nor without intelligent information retrieval tools.

Acoustic waveform of continuous bubbling in a non-Newtonian fluid.

PubMed

Vidal, Valérie; Ichihara, Mie; Ripepe, Maurizio; Kurita, Kei

2009-12-01

We study experimentally the acoustic signal associated with a continuous bubble bursting at the free surface of a non-Newtonian fluid. Due to the fluid rheological properties, the bubble shape is elongated, and, when bursting at the free surface, acts as a resonator. For a given fluid concentration, at constant flow rate, repetitive bubble bursting occurs at the surface. We report a modulation pattern of the acoustic waveform through time. Moreover, we point out the existence of a precursor acoustic signal, recorded on the microphone array, previous to each bursting. The time delay between this precursor and the bursting signal is well correlated with the bursting signal frequency content. Their joint modulation through time is driven by the fluid rheology, which strongly depends on the presence of small satellite bubbles trapped in the fluid due to the yield stress.

Magnetically Actuated Propellant Orientation, Controlling Fluids in a Low-Gravity Environment

NASA Technical Reports Server (NTRS)

Martin, James J.; Holt, James B.

2000-01-01

Cryogenic fluid management (CFM) is a technology area common to virtually every space transportation propulsion concept envisioned. Storage, supply, transfer and handling of sub-critical cryogenic fluids are basic capabilities that have long been needed by multiple programs and the need is expected to continue in the future. The use of magnetic fields provides another method, which could replace or augment current/traditional approaches, potentially simplifying vehicle operational constraints. The magnetically actuated propellant orientation (MAPO) program effort focused on the use of magnetic fields to control fluid motion as it relates to positioning (i.e. orientation and acquisition) of a paramagnetic substance such as LO2. Current CFM state- of-the-art systems used to control and acquire propellant in low gravity environments rely on liquid surface tension devices which employ vanes, fine screen mesh channels and baskets. These devices trap and direct propellant to areas where it's needed and have been used routinely with storable (non-cryogenic) propellants. However, almost no data exists r,egarding their operation in cryogenics and the use of such devices confronts designers with a multitude of significant technology issues. Typical problems include a sensitivity to screen dry out (due to thermal loads and pressurant gas) and momentary adverse accelerations (generated from either internal or external sources). Any of these problems can potentially cause the acquisition systems to ingest or develop vapor and fail. The use of lightweight high field strength magnets may offer a valuable means of augmenting traditional systems potentially mitigating or at least easing operational requirements. Two potential uses of magnetic fields include: 1) strategically positioning magnets to keep vent ports clear of liquid (enabling low G vented fill operations), and 2) placing magnets in the center or around the walls of the tank to create an insulating vapor pocket (between the liquid and the tank wall) which could effectively lower heat transfer to the liquid (enabling increased storage time).

Mesoscopic modeling of structural and thermodynamic properties of fluids confined by rough surfaces.

PubMed

Terrón-Mejía, Ketzasmin A; López-Rendón, Roberto; Gama Goicochea, Armando

2015-10-21

The interfacial and structural properties of fluids confined by surfaces of different geometries are studied at the mesoscopic scale using dissipative particle dynamics simulations in the grand canonical ensemble. The structure of the surfaces is modeled by a simple function, which allows us to simulate readily different types of surfaces through the choice of three parameters only. The fluids we have modeled are confined either by two smooth surfaces or by symmetrically and asymmetrically structured walls. We calculate structural and thermodynamic properties such as the density, temperature and pressure profiles, as well as the interfacial tension profiles for each case and find that a structural order-disorder phase transition occurs as the degree of surface roughness increases. However, the magnitude of the interfacial tension is insensitive to the structuring of the surfaces and depends solely on the magnitude of the solid-fluid interaction. These results are important for modern nanotechnology applications, such as in the enhanced recovery of oil, and in the design of porous materials with specifically tailored properties.

Evaluating a vessel for suitability for containing fluid

DOEpatents

Barefield, II, James E.; Judge, Elizabeth J.; Le, Loan A.; Lopez, Leon N.; Beveridge, Andrew C.; Chapman, Daniel R.; Taylor, Seth T.

2017-05-30

A method for evaluating a vessel for suitability to contain a fluid includes providing a vessel and forming a polished surface portion of the vessel by removing oxidation and/or contaminants from a portion of the vessel. The method further includes applying a focused laser to the polished surface portion to form plasma on the polished surface portion, and determining whether the vessel is suitable for containing a fluid based on silicon content of the polished surface portion. The silicon content is estimated based on light emitted from the plasma.

High resolution printing of charge

DOEpatents

Rogers, John; Park, Jang-Ung

2015-06-16

Provided are methods of printing a pattern of charge on a substrate surface, such as by electrohydrodynamic (e-jet) printing. The methods relate to providing a nozzle containing a printable fluid, providing a substrate having a substrate surface and generating from the nozzle an ejected printable fluid containing net charge. The ejected printable fluid containing net charge is directed to the substrate surface, wherein the net charge does not substantially degrade and the net charge retained on the substrate surface. Also provided are functional devices made by any of the disclosed methods.

Deionization and desalination using electrostatic ion pumping

DOEpatents

Bourcier, William L.; Aines, Roger D.; Haslam, Jeffery J.; Schaldach, Charlene M.; O& #x27; Brien, Kevin C.; Cussler, Edward

2013-06-11

The present invention provides a new method and apparatus/system for purifying ionic solutions, such as, for example, desalinating water, using engineered charged surfaces to sorb ions from such solutions. Surface charge is applied externally, and is synchronized with oscillatory fluid movements between substantially parallel charged plates. Ions are held in place during fluid movement in one direction (because they are held in the electrical double layer), and released for transport during fluid movement in the opposite direction by removing the applied electric field. In this way the ions, such as salt, are "ratcheted" across the charged surface from the feed side to the concentrate side. The process itself is very simple and involves only pumps, charged surfaces, and manifolds for fluid collection.

Deionization and desalination using electrostatic ion pumping

DOEpatents

Bourcier, William L [Livermore, CA; Aines, Roger D [Livermore, CA; Haslam, Jeffery J [Livermore, CA; Schaldach, Charlene M [Pleasanton, CA; O'Brien, Kevin C [San Ramon, CA; Cussler, Edward [Edina, MN

2011-07-19

The present invention provides a new method and apparatus/system for purifying ionic solutions, such as, for example, desalinating water, using engineered charged surfaces to sorb ions from such solutions. Surface charge is applied externally, and is synchronized with oscillatory fluid movements between substantially parallel charged plates. Ions are held in place during fluid movement in one direction (because they are held in the electrical double layer), and released for transport during fluid movement in the opposite direction by removing the applied electric field. In this way the ions, such as salt, are "ratcheted" across the charged surface from the feed side to the concentrate side. The process itself is very simple and involves only pumps, charged surfaces, and manifolds for fluid collection.

Effects of Surface Roughness on Conical Squeeze Film Bearings with Micropolar fluid

NASA Astrophysics Data System (ADS)

Rajani, C. B.; Hanumagowda, B. N.; Shigehalli, Vijayalaxmi S.

2018-04-01

In the current paper, a hypothetical analysis of the impact of surface roughness on squeeze film lubrication of rough conical bearing using Micropolar fluid is examined using Eringen’sMicropolar fluid model. The generalized averaged Reynolds type equation for roughness has been determined analytically using the Christensen’s stochastic theory of roughness effects and the closed form expressions are obtained for the fluid film pressure, load carrying capacity and squeezing time. Further, the impacts of surface roughness using micropolar fluids on the squeeze film lubrication of rough conical bearings has been discussed and according to the outcomes arrived, pressure, load carrying capacity and squeezing time increases for azimuthal roughness pattern and decreases for radial roughness patterns comparatively to the smooth case.

On the inclusion of mass source terms in a single-relaxation-time lattice Boltzmann method

NASA Astrophysics Data System (ADS)

Aursjø, Olav; Jettestuen, Espen; Vinningland, Jan Ludvig; Hiorth, Aksel

2018-05-01

We present a lattice Boltzmann algorithm for incorporating a mass source in a fluid flow system. The proposed mass source/sink term, included in the lattice Boltzmann equation, maintains the Galilean invariance and the accuracy of the overall method, while introducing a mass source/sink term in the fluid dynamical equations. The method can, for instance, be used to inject or withdraw fluid from any preferred lattice node in a system. This suggests that injection and withdrawal of fluid does not have to be introduced through cumbersome, and sometimes less accurate, boundary conditions. The method also suggests that, through a chosen equation of state relating mass density to pressure, the proposed mass source term will render it possible to set a preferred pressure at any lattice node in a system. We demonstrate how this model handles injection and withdrawal of a fluid. And we show how it can be used to incorporate pressure boundaries. The accuracy of the algorithm is identified through a Chapman-Enskog expansion of the model and supported by the numerical simulations.

Automated Extraction of Flow Features

NASA Technical Reports Server (NTRS)

Dorney, Suzanne (Technical Monitor); Haimes, Robert

2005-01-01

Computational Fluid Dynamics (CFD) simulations are routinely performed as part of the design process of most fluid handling devices. In order to efficiently and effectively use the results of a CFD simulation, visualization tools are often used. These tools are used in all stages of the CFD simulation including pre-processing, interim-processing, and post-processing, to interpret the results. Each of these stages requires visualization tools that allow one to examine the geometry of the device, as well as the partial or final results of the simulation. An engineer will typically generate a series of contour and vector plots to better understand the physics of how the fluid is interacting with the physical device. Of particular interest are detecting features such as shocks, re-circulation zones, and vortices (which will highlight areas of stress and loss). As the demand for CFD analyses continues to increase the need for automated feature extraction capabilities has become vital. In the past, feature extraction and identification were interesting concepts, but not required in understanding the physics of a steady flow field. This is because the results of the more traditional tools like; isc-surface, cuts and streamlines, were more interactive and easily abstracted so they could be represented to the investigator. These tools worked and properly conveyed the collected information at the expense of a great deal of interaction. For unsteady flow-fields, the investigator does not have the luxury of spending time scanning only one "snapshot" of the simulation. Automated assistance is required in pointing out areas of potential interest contained within the flow. This must not require a heavy compute burden (the visualization should not significantly slow down the solution procedure for co-processing environments). Methods must be developed to abstract the feature of interest and display it in a manner that physically makes sense.

Automated Extraction of Flow Features

NASA Technical Reports Server (NTRS)

Dorney, Suzanne (Technical Monitor); Haimes, Robert

2004-01-01

Computational Fluid Dynamics (CFD) simulations are routinely performed as part of the design process of most fluid handling devices. In order to efficiently and effectively use the results of a CFD simulation, visualization tools are often used. These tools are used in all stages of the CFD simulation including pre-processing, interim-processing, and post-processing, to interpret the results. Each of these stages requires visualization tools that allow one to examine the geometry of the device, as well as the partial or final results of the simulation. An engineer will typically generate a series of contour and vector plots to better understand the physics of how the fluid is interacting with the physical device. Of particular interest are detecting features such as shocks, recirculation zones, and vortices (which will highlight areas of stress and loss). As the demand for CFD analyses continues to increase the need for automated feature extraction capabilities has become vital. In the past, feature extraction and identification were interesting concepts, but not required in understanding the physics of a steady flow field. This is because the results of the more traditional tools like; iso-surface, cuts and streamlines, were more interactive and easily abstracted so they could be represented to the investigator. These tools worked and properly conveyed the collected information at the expense of a great deal of interaction. For unsteady flow-fields, the investigator does not have the luxury of spending time scanning only one "snapshot" of the simulation. Automated assistance is required in pointing out areas of potential interest contained within the flow. This must not require a heavy compute burden (the visualization should not significantly slow down the solution procedure for (co-processing environments). Methods must be developed to abstract the feature of interest and display it in a manner that physically makes sense.

Physically-Based Modelling and Real-Time Simulation of Fluids.

NASA Astrophysics Data System (ADS)

Chen, Jim Xiong

1995-01-01

Simulating physically realistic complex fluid behaviors presents an extremely challenging problem for computer graphics researchers. Such behaviors include the effects of driving boats through water, blending differently colored fluids, rain falling and flowing on a terrain, fluids interacting in a Distributed Interactive Simulation (DIS), etc. Such capabilities are useful in computer art, advertising, education, entertainment, and training. We present a new method for physically-based modeling and real-time simulation of fluids in computer graphics and dynamic virtual environments. By solving the 2D Navier -Stokes equations using a CFD method, we map the surface into 3D using the corresponding pressures in the fluid flow field. This achieves realistic real-time fluid surface behaviors by employing the physical governing laws of fluids but avoiding extensive 3D fluid dynamics computations. To complement the surface behaviors, we calculate fluid volume and external boundary changes separately to achieve full 3D general fluid flow. To simulate physical activities in a DIS, we introduce a mechanism which uses a uniform time scale proportional to the clock-time and variable time-slicing to synchronize physical models such as fluids in the networked environment. Our approach can simulate many different fluid behaviors by changing the internal or external boundary conditions. It can model different kinds of fluids by varying the Reynolds number. It can simulate objects moving or floating in fluids. It can also produce synchronized general fluid flows in a DIS. Our model can serve as a testbed to simulate many other fluid phenomena which have never been successfully modeled previously.

Interaction of Strong Turbulence With Free Surfaces

NASA Astrophysics Data System (ADS)

Dalrymple, Robert A.

Spray from a nozzle, spilling breakers, and “rooster tails” from speeding boats are all examples of a turbulent flow with a free surface. In many cases like these, the free surface is difficult to discern as the volume of air in the fluid can exceed that of the water.In traditional studies, the free surface is simply defined as a continuous surface separating the fluid from air. The pressure at the surface is assumed to be atmospheric pressure and the fluid comprising the surface moves with the surface. While these conditions are sufficient for non-turbulent flows, such as nonbreaking water waves, and lead to the (albeit non-linear) dynamic and kinematic free surface boundary conditions that serve to provide sufficient conditions to determine the surface, they are not valid descriptions for a bubbly free surface in a highly turbulent regime, such as the roller in front of a spilling breaker or the propeller wash behind a ship.

Effective slip identities for viscous flow over arbitrary patterned surfaces

NASA Astrophysics Data System (ADS)

Kamrin, Ken; Six, Pierre

2012-11-01

For a variety of applications, most recently microfluidics, the ability to control fluid motions using surface texturing has been an area of ongoing interest. In this talk, we will develop several identities relating to the construction of effective slip boundary conditions for patterned surfaces. The effective slip measures the apparent slip of a fluid layer flowing over a patterned surface when viewing the flow far from the surface. In specific, shear flows of tall fluid layers over periodic surfaces (surfaces perturbed from a planar no-slip boundary by height and/or hydrophobicity fluctuations) are governed by an effective slip matrix that relates the vector of far-field shear stress (applied to the top of the fluid layer) to the effective slip velocity vector that emerges from the flow. Of particular note, we will demonstrate several general rules that describe the effective slip matrix: (1) that the effective slip matrix is always symmetric, (2) that the effective slip over any hydrophobically striped surface implies a family of related results for slip over other striped surfaces, and (3) that when height or hydrophobicity fluctuations are small, the slip matrix can be approximated directly using a simple formula derived from the surface pattern.

Electrolyte-Sensing Transistor Decals Enabled by Ultrathin Microbial Nanocellulose

PubMed Central

Yuen, Jonathan D.; Walper, Scott A.; Melde, Brian J.; Daniele, Michael A.; Stenger, David A.

2017-01-01

We report an ultra-thin electronic decal that can simultaneously collect, transmit and interrogate a bio-fluid. The described technology effectively integrates a thin-film organic electrochemical transistor (sensing component) with an ultrathin microbial nanocellulose wicking membrane (sample handling component). As far as we are aware, OECTs have not been integrated in thin, permeable membrane substrates for epidermal electronics. The design of the biocompatible decal allows for the physical isolation of the electronics from the human body while enabling efficient bio-fluid delivery to the transistor via vertical wicking. High currents and ON-OFF ratios were achieved, with sensitivity as low as 1 mg·L−1. PMID:28102316

Electrolyte-Sensing Transistor Decals Enabled by Ultrathin Microbial Nanocellulose

NASA Astrophysics Data System (ADS)

Yuen, Jonathan D.; Walper, Scott A.; Melde, Brian J.; Daniele, Michael A.; Stenger, David A.

2017-01-01

We report an ultra-thin electronic decal that can simultaneously collect, transmit and interrogate a bio-fluid. The described technology effectively integrates a thin-film organic electrochemical transistor (sensing component) with an ultrathin microbial nanocellulose wicking membrane (sample handling component). As far as we are aware, OECTs have not been integrated in thin, permeable membrane substrates for epidermal electronics. The design of the biocompatible decal allows for the physical isolation of the electronics from the human body while enabling efficient bio-fluid delivery to the transistor via vertical wicking. High currents and ON-OFF ratios were achieved, with sensitivity as low as 1 mg·L-1.

Modeling for free surface flow with phase change and its application to fusion technology

NASA Astrophysics Data System (ADS)

Luo, Xiaoyong

The development of predictive capabilities for free surface flow with phase change is essential to evaluate liquid wall protection schemes for various fusion chambers. With inertial fusion energy (IFE) concepts such as HYLIFE-II, rapid condensation into cold liquid surfaces is required when using liquid curtains for protecting reactor walls from blasts and intense neutron radiation. With magnetic fusion energy (MFE) concepts, droplets are injected onto the free surface of the liquid to minimize evaporation by minimizing the surface temperature. This dissertation presents a numerical methodology for free surface flow with phase change to help resolve feasibility issues encountered in the aforementioned fusion engineering fields, especially spray droplet condensation efficiency in IFE and droplet heat transfer enhancement on free surface liquid divertors in MFE. The numerical methodology is being conducted within the framework of the incompressible flow with the phase change model. A new second-order projection method is presented in conjunction with Approximate-Factorization techniques (AF method) for incompressible Navier-Stokes equations. A sub-cell conception is introduced and the Ghost Fluid Method in extended in a modified mass transfer model to accurately calculate the mass transfer across the interface. The Crank-Nicholson method is used for the diffusion term to eliminate the numerical viscous stability restriction. The third-order ENO scheme is used for the convective term to guarantee the accuracy of the method. The level set method is used to capture accurately the free surface of the flow and the deformation of the droplets. This numerical investigation identifies the physics characterizing transient heat and mass transfer of the droplet and the free surface flow. The results show that the numerical methodology is quite successful in modeling the free surface with phase change even though some severe deformations such as breaking and merging occur. The versatility of the numerical methodology shows that the work can easily handle complex physical conditions that occur in the fusion science and engineering.

30 CFR 56.12014 - Handling energized power cables.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...

30 CFR 56.12014 - Handling energized power cables.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...

30 CFR 56.12014 - Handling energized power cables.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...

30 CFR 56.12014 - Handling energized power cables.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...

30 CFR 56.12014 - Handling energized power cables.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...

On Energy Inequality for the Problem on the Evolution of Two Fluids of Different Types Without Surface Tension

NASA Astrophysics Data System (ADS)

Denisova, Irina Vlad.

2015-03-01

The paper deals with the motion of two immiscible viscous fluids in a container, one of the fluids being compressible while another one being incompressible. The interface between the fluids is an unknown closed surface where surface tension is neglected. We assume the compressible fluid to be barotropic, the pressure being given by an arbitrary smooth increasing function. This problem is considered in anisotropic Sobolev-Slobodetskiǐ spaces. We show that the L 2-norms of the velocity and deviation of compressible fluid density from the mean value decay exponentially with respect to time. The proof is based on a local existence theorem (Denisova, Interfaces Free Bound 2:283-312, 2000) and on the idea of constructing a function of generalized energy, proposed by Padula (J Math Fluid Mech 1:62-77, 1999). In addition, we eliminate the restrictions for the viscosities which appeared in Denisova (Interfaces Free Bound 2:283-312, 2000).

Influence of a thin compressible insoluble liquid film on the eddy currents generated by interacting surface waves

NASA Astrophysics Data System (ADS)

Parfenyev, Vladimir M.; Vergeles, Sergey S.

2018-06-01

Recently the generation of eddy currents by interacting surface waves was observed experimentally. The phenomenon provides the possibility for manipulation of particles which are immersed in the fluid. The analysis shows that the amplitude of the established eddy currents produced by stationary surface waves does not depend on the fluid viscosity in the free surface case. The currents become parametrically larger, being inversely proportional to the square root of the fluid viscosity in the case when the fluid surface is covered by an almost incompressible thin liquid (i.e., shear elasticity is zero) film formed by an insoluble agent with negligible internal viscous losses as compared to the dissipation in the fluid bulk. Here we extend the theory for a thin insoluble film with zero shear elasticity and small shear and dilational viscosities on the case of an arbitrary elastic compression modulus. We find both contributions into the Lagrangian motion of passive tracers, which are the advection by the Eulerian vertical vorticity and the Stokes drift. Whereas the Stokes drift contribution preserves its value for the free surface case outside a thin viscous sublayer, the Eulerian vertical vorticity strongly depends on the fluid viscosity at high values of the film compression modulus. The Stokes drift acquires a strong dependence on the fluid viscosity inside the viscous sublayer; however, the change is compensated by an opposite change in the Eulerian vertical vorticity. As a result, the vertical dependence of the intensity of eddy currents is given by a sum of two decaying exponents with both decrements being of the order of the wave number. The decrements are numerically different, so the Eulerian contribution becomes dominant at some depth for the surface film with any compression modulus.

Anomalous sorption of supercritical fluids on polymer thin films.

PubMed

Wang, Xiaochu; Sanchez, Isaac C

2006-10-24

Unusual sorption has been reported in thin polymer films exposed to near-critical CO2. When the supercritical fluid approaches the critical point, the film appears to thicken, but it is not clear whether the film swells or there is an adsorption layer on the film surface. A combination of the gradient theory of inhomogeneous systems and the Sanchez-Lacombe equation of state has been used to investigate this phenomenon. It is shown analytically that surface adsorption on an attractive surface is proportional to the compressibility of the fluid. We have also investigated numerically the sorption of supercritical CO2 on poly(dimethylsiloxane) and polyisobutylene, and supercritical 1,1-difluoroethane on polystyrene. By calculating the Gibbs adsorption and adsorption layer thickness of the supercritical fluids, we found in all cases (different substrates, different supercritical fluids) that maximum adsorption occurs when the supercritical fluid is near its compressibility maximum.

Interfacial gauge methods for incompressible fluid dynamics

PubMed Central

Saye, Robert

2016-01-01

Designing numerical methods for incompressible fluid flow involving moving interfaces, for example, in the computational modeling of bubble dynamics, swimming organisms, or surface waves, presents challenges due to the coupling of interfacial forces with incompressibility constraints. A class of methods, denoted interfacial gauge methods, is introduced for computing solutions to the corresponding incompressible Navier-Stokes equations. These methods use a type of “gauge freedom” to reduce the numerical coupling between fluid velocity, pressure, and interface position, allowing high-order accurate numerical methods to be developed more easily. Making use of an implicit mesh discontinuous Galerkin framework, developed in tandem with this work, high-order results are demonstrated, including surface tension dynamics in which fluid velocity, pressure, and interface geometry are computed with fourth-order spatial accuracy in the maximum norm. Applications are demonstrated with two-phase fluid flow displaying fine-scaled capillary wave dynamics, rigid body fluid-structure interaction, and a fluid-jet free surface flow problem exhibiting vortex shedding induced by a type of Plateau-Rayleigh instability. The developed methods can be generalized to other types of interfacial flow and facilitate precise computation of complex fluid interface phenomena. PMID:27386567

Triple electrical channels on a triple fluid swivel and its use to monitor intracranial temperature with a thermocouple.

PubMed

Parada, M A; Puig de Parada, M; Hernandez, L; Hoebel, B G

1995-08-01

A low-torque, bubble-free and multiple-channel fluid swivel of easy construction was recently described. This paper describes the design, construction and testing of 3 electrical channels added to the original fluid swivel. The new channels were tested monitoring intrahypothalamic temperature (T(hy)) by means of a copper-constantan thermocouple in freely moving rats, before and after a single intraperitoneal (i.p.) amphetamine injection (3 mg/kg). This test showed an increase in T(hy) after the injection and the maintenance of the electrical continuity along the whole testing period, even when the animals were hyperactive. With this improvement the original swivel was transformed in a more versatile device for experiments requiring fluid handlings and electrophysiological manipulations. Electrical stimulation as in kindling or brain self-stimulation, and electrophysiological recordings as in electroencephalography, electromiography, electrocardiography, in vivo voltammetry and even neuronal unit recording, are just examples of the electrophysiological methods that can be combined with drug self-administration and microdialysis using the present device.

Flexible Inhibitor Fluid-Structure Interaction Simulation in RSRM.

NASA Astrophysics Data System (ADS)

Wasistho, Bono

2005-11-01

We employ our tightly coupled fluid/structure/combustion simulation code 'Rocstar-3' for solid propellant rocket motors to study 3D flows past rigid and flexible inhibitors in the Reusable Solid Rocket Motor (RSRM). We perform high resolution simulations of a section of the rocket near the center joint slot at 100 seconds after ignition, using inflow conditions based on less detailed 3D simulations of the full RSRM. Our simulations include both inviscid and turbulent flows (using LES dynamic subgrid-scale model), and explore the interaction between the inhibitor and the resulting fluid flow. The response of the solid components is computed by an implicit finite element solver. The internal mesh motion scheme in our block-structured fluid solver enables our code to handle significant changes in geometry. We compute turbulent statistics and determine the compound instabilities originated from the natural hydrodynamic instabilities and the inhibitor motion. The ultimate goal is to studdy the effect of inhibitor flexing on the turbulent field.

The surface diffusion coefficient for an arbitrarily curved fluid-fluid interface. (I). General expression

NASA Astrophysics Data System (ADS)

M. C. Sagis, Leonard

2001-03-01

In this paper, we develop a theory for the calculation of the surface diffusion coefficient for an arbitrarily curved fluid-fluid interface. The theory is valid for systems in hydrodynamic equilibrium, with zero mass-averaged velocities in the bulk and interfacial regions. We restrict our attention to systems with isotropic bulk phases, and an interfacial region that is isotropic in the plane parallel to the dividing surface. The dividing surface is assumed to be a simple interface, without memory effects or yield stresses. We derive an expression for the surface diffusion coefficient in terms of two parameters of the interfacial region: the coefficient for plane-parallel diffusion D (AB)aa(ξ) , and the driving force d(B)I||(ξ) . This driving force is the parallel component of the driving force for diffusion in the interfacial region. We derive an expression for this driving force using the entropy balance.

Dynamics of skirting droplets

NASA Astrophysics Data System (ADS)

Akers, Caleb; Hale, Jacob

2014-11-01

It has been observed that non-coalescence between a droplet and pool of like fluid can be prolonged or inhibited by sustained relative motion between the two fluids. In this study, we quantitatively describe the motion of freely moving droplets that skirt across the surface of a still pool of like fluid. Droplets of different sizes and small Weber number were directed horizontally onto the pool surface. After stabilization of the droplet shape after impact, the droplets smoothly moved across the surface, slowing until coalescence. Using high-speed imaging, we recorded the droplet's trajectory from a top-down view as well as side views both slightly above and below the fluid surface. The droplets' speed is observed to decrease exponentially, with the smaller droplets slowing down at a greater rate. Droplets infused with neutral density micro beads showed that the droplet rolls along the surface of the pool. A qualitative model of this motion is presented.

Wave propagation in fluid-conveying viscoelastic single-walled carbon nanotubes with surface and nonlocal effects

NASA Astrophysics Data System (ADS)

Zhen, Ya-Xin

2017-02-01

In this paper, the transverse wave propagation in fluid-conveying viscoelastic single-walled carbon nanotubes is investigated based on nonlocal elasticity theory with consideration of surface effect. The governing equation is formulated utilizing nonlocal Euler-Bernoulli beam theory and Kelvin-Voigt model. Explicit wave dispersion relation is developed and wave phase velocities and frequencies are obtained. The effect of the fluid flow velocity, structural damping, surface effect, small scale effects and tube diameter on the wave propagation properties are discussed with different wave numbers. The wave frequency increases with the increase of fluid flow velocity, but decreases with the increases of tube diameter and wave number. The effect of surface elasticity and residual surface tension is more significant for small wave number and tube diameter. For larger values of wave number and nonlocal parameters, the real part of frequency ratio raises.

Method of separating organic contaminants from fluid feedstreams with polyphosphazene membranes

DOEpatents

McCaffrey, Robert R.; Cummings, Daniel G.

1991-01-01

A method is provided for separating halogenated hydrocarbons from a fluid feedstream. The fluid feedstream is flowed across a first surface of a polyphosphazene semipermeable membrane. At least one halogenated hydrocarbon from the fluid feedstream permeates through the polyphosphazene semipermeable membrane to a second opposed surface of the semipermeable membrane. Then the permeated polar hydrocarbon is removed from the second opposed surface of the polyphosphazene semipermeable membrane. Outstanding and unexpected separation selectivities on the order of 10,000 were obtained for methylene chloride when a methylene chloride in water feedstream was flowed across the polyphosphazene semipermeable membrane in the invented method.

Relation between boundary slip mechanisms and waterlike fluid behavior.

PubMed

Ternes, Patricia; Salcedo, Evy; Barbosa, Marcia C

2018-03-01

The slip of a fluid layer in contact with a solid confining surface is investigated for different temperatures and densities using molecular dynamic simulations. We show that for an anomalous waterlike fluid the slip goes as follows: for low levels of shear, defect slip appears and is related to the particle exchange between the fluid layers; at high levels of shear, global slip occurs and is related to the homogeneous distribution of the fluid in the confining surfaces. The oscillations in the transition velocity from defect to global slip are shown to be associated with changes in the layering distribution in the anomalous fluid.

Modular robot

DOEpatents

Ferrante, Todd A.

1997-01-01

A modular robot may comprise a main body having a structure defined by a plurality of stackable modules. The stackable modules may comprise a manifold, a valve module, and a control module. The manifold may comprise a top surface and a bottom surface having a plurality of fluid passages contained therein, at least one of the plurality of fluid passages terminating in a valve port located on the bottom surface of the manifold. The valve module is removably connected to the manifold and selectively fluidically connects the plurality of fluid passages contained in the manifold to a supply of pressurized fluid and to a vent. The control module is removably connected to the valve module and actuates the valve module to selectively control a flow of pressurized fluid through different ones of the plurality of fluid passages in the manifold. The manifold, valve module, and control module are mounted together in a sandwich-like manner and comprise a main body. A plurality of leg assemblies are removably connected to the main body and are removably fluidically connected to the fluid passages in the manifold so that each of the leg assemblies can be selectively actuated by the flow of pressurized fluid in different ones of the plurality of fluid passages in the manifold.

Surface finishing. [for aircraft wings

NASA Technical Reports Server (NTRS)

Kinzler, J. A.; Heffernan, J. T.; Fehrenkamp, L. G.; Lee, W. S. (Inventor)

1977-01-01

A surface of an article adapted for relative motion with a fluid environment is finished by coating the surface with a fluid adhesive. The adhesive is covered with a sheet of flexible film material under tension, and the adhesive is set while maintaining tension on the film material.

Software Surface Modeling and Grid Generation Steering Committee

NASA Technical Reports Server (NTRS)

Smith, Robert E. (Editor)

1992-01-01

It is a NASA objective to promote improvements in the capability and efficiency of computational fluid dynamics. Grid generation, the creation of a discrete representation of the solution domain, is an essential part of computational fluid dynamics. However, grid generation about complex boundaries requires sophisticated surface-model descriptions of the boundaries. The surface modeling and the associated computation of surface grids consume an extremely large percentage of the total time required for volume grid generation. Efficient and user friendly software systems for surface modeling and grid generation are critical for computational fluid dynamics to reach its potential. The papers presented here represent the state-of-the-art in software systems for surface modeling and grid generation. Several papers describe improved techniques for grid generation.

BIGHORN Computational Fluid Dynamics Theory, Methodology, and Code Verification & Validation Benchmark Problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xia, Yidong; Andrs, David; Martineau, Richard Charles

This document presents the theoretical background for a hybrid finite-element / finite-volume fluid flow solver, namely BIGHORN, based on the Multiphysics Object Oriented Simulation Environment (MOOSE) computational framework developed at the Idaho National Laboratory (INL). An overview of the numerical methods used in BIGHORN are discussed and followed by a presentation of the formulation details. The document begins with the governing equations for the compressible fluid flow, with an outline of the requisite constitutive relations. A second-order finite volume method used for solving the compressible fluid flow problems is presented next. A Pressure-Corrected Implicit Continuous-fluid Eulerian (PCICE) formulation for timemore » integration is also presented. The multi-fluid formulation is being developed. Although multi-fluid is not fully-developed, BIGHORN has been designed to handle multi-fluid problems. Due to the flexibility in the underlying MOOSE framework, BIGHORN is quite extensible, and can accommodate both multi-species and multi-phase formulations. This document also presents a suite of verification & validation benchmark test problems for BIGHORN. The intent for this suite of problems is to provide baseline comparison data that demonstrates the performance of the BIGHORN solution methods on problems that vary in complexity from laminar to turbulent flows. Wherever possible, some form of solution verification has been attempted to identify sensitivities in the solution methods, and suggest best practices when using BIGHORN.« less

Initial operation with sodium in the Madison Dynamo Experiment.

NASA Astrophysics Data System (ADS)

Kendrick, R.; Spence, Ej; Forest, C. B.; O'Connell, R.; Nornberg, Md; Canary, Hw; Wright, A.; Robinson, K.

1999-11-01

A new liquid metal MHD experiment has been constructed at the University of Wisconsin to test several key predictions of dynamo theory: magnetic instabilities driven by sheared flow, the effects of turbulence on current generation, and the back-reaction of the self-generated magnetic field on the fluid motion which brings saturation. This presentation describes the engineering design of the experiment, which is a 0.5 m radius spherical vessel, filled with liquid sodium at 150 ^circC. The experiment is designed to achieve a magnetic Reynolds number in excess of 100, which requires approximately 80 Hp of mechanical drive, producing flow velocities in sodium of 15 m/s through impellers. Handling liquid sodium offers a number of technical challenges, but routine techniques have been developed over the past several decades for safely handling large quantities for the fast breeder reactor. The handling strategy is discussed, technical details concerning seals and pressurization are presented, and safety elements are highlighted.

Expression of pericardial fluid T-cells and related inflammatory cytokines in patients with chronic heart failure.

PubMed

Iskandar, Reinard; Liu, Shengchen; Xiang, Fei; Chen, Wen; Li, Liangpeng; Qin, Wei; Huang, Fuhua; Chen, Xin

2017-05-01

Pericardial fluid, as a biochemical indicator of heart status, directly indicates pathological alteration to the heart. The accumulation of pericardial fluid can be attributed to an underlying systemic or local inflammatory process. However, the pericardial fluid expression of cellular surface markers, as well as several cytokines in chronic heart failure (CHF), remain unclear. In order to evaluate these issues further the pericardial fluid expression of several cytokines and the surface expression of activity markers between CHF patients and non-heart failure (NHF) patients were analyzed. The pericardial fluid expression of cytokines was measured by immunofluorescence and biomarker of plasma N-terminal propeptide of B-type natriuretic peptide (NT-proBNP), while pericardial fluid levels of soluble glycoprotein 130 (sgp130) were analyzed by ELISA in 50 CHF and 24 NHF patients. In addition, the surface expression of activation markers for T-cells was measured by immunohistochemistry. Patients with CHF demonstrated increased levels of plasma NT-proBNP and pericardial fluid sgp130. Surface expression of cellular activation markers CD25 and Foxp3 in the pericardial fluid was increased in patients with CHF. Moreover, the pro- and anti-inflammatory cytokines interferon (IFN)-γ, interleukin (IL)-6 and IL-10 in patients with CHF also demonstrated an increased expression within its pericardial fluid. In addition, there was infiltration of inflammatory cells and enhanced expression of inflammatory cytokines in the pericardial fluid of patients with CHF, which may reflect T cell activation, suggesting that systemic inflammation is important in the progression of CHF. This evidence could indicate a possible novel target for future therapeutics and prevention of CHF.

PESTICIDE SURFACE RESIDUE MEASUREMENTS BY A PRESS SAMPLER

EPA Science Inventory

Pesticides on household surfaces are a source of exposure to children. Accurate measurements of residues on surfaces are needed to determine amounts available for transfer to foods and other objects handled or eaten by a child. Wiping the surface with a solvent has been the acc...

Enhancement of Boiling Heat Transfer in Di-Electric Fluids

DTIC Science & Technology

1991-09-01

working fluid of R-I13. Maddox and Mudawar [Ref. 8] studied the effect of subcooling and surface aug- mentation on values of Critical Heat Flux (CHF). They...Enhanced Surfaces to Dielectric Fluids," A SME Journal of Heat Transfer, v.104, pp.292-299, May 1982. 8. Maddox D.E., and Mudawar ,I., "Single and Two

Environmental and biological monitoring on an oncology ward during a complete working week.

PubMed

Koller, Michael; Böhlandt, Antje; Haberl, Christopher; Nowak, Dennis; Schierl, Rudolf

2018-05-05

Workplace exposure to antineoplastic drugs (AD) is still of evident concern to all occupationally exposed persons in the healthcare sector as residues in relevant concentrations continue to be present. With respect to the carcinogenic and mutagenic potential of ADs and their toxicity on reproduction, occupational exposure should be kept as low as reasonably achievable (ALARA). In the oncology patient care, the medical staff is involved both in chemotherapy administration and handling of AD-contaminated body fluids of the patients. For this purpose, in this study, surface monitoring on an oncology ward and concurrent urine monitoring of the complete healthcare staff was performed during five consecutive days for 5-fluorouracil (5-FU), cyclophosphamide (CP) and platinum (Pt). Contamination was detected on all surfaces in various ranges (5-FU 0.7-12,600 pg/cm 2 , Pt 0.2-181,800 pg/cm 2 , CP (

Walkaway-VSP survey using distributed optical fiber in China oilfield

NASA Astrophysics Data System (ADS)

Wu, Junjun; Yu, Gang; Zhang, Qinghong; Li, Yanpeng; Cai, Zhidong; Chen, Yuanzhong; Liu, Congwei; Zhao, Haiying; Li, Fei

2017-10-01

Distributed acoustic sensing (DAS) is a new type of replacement technology for geophysical geophone. DAS system is similar to high-density surface seismic geophone array. In the stage of acquisition, DAS can obtain the full well data with one shot. And it can provide enhanced vertical seismic profile (VSP) imaging and monitor fluids and pressures changes in the hydrocarbon production reservoir. Walkaway VSP data acquired over a former producing well in north eastern China provided a rich set of very high quality data. A standard VSP data pre-processing workflow was applied, followed by pre-stack Kirchhoff time migration. In the DAS pre-processing step we were faced with additional and special challenges: strong coherent noise due to cable slapping and ringing along the borehole casing. The single well DAS Walkaway VSP images provide a good result with higher vertical and lateral resolution than the surface seismic in the objective area. This paper reports on lessons learned in the handling of the wireline cable and subsequent special DAS data processing steps developed to remediate some of the practical wireline deployment issues. Optical wireline cable as a conveyance of fiber optic cables for VSP in vertical wells will open the use of the DAS system to much wider applications.

Low-leakage and low-instability labyrinth seal

NASA Technical Reports Server (NTRS)

Rhode, David L. (Inventor)

1997-01-01

Improved labyrinth seal designs are disclosed. The present invention relates to labyrinth seal systems with selected sealing surfaces and seal geometry to optimize flow deflection and produce maximum turbulent action. Optimum seal performance is generally accomplished by providing sealing surfaces and fluid cavities formed to dissipate fluid energy as a function of the geometry of the sealing surfaces along with the position and size of the fluid cavities formed between members of the labyrinth seal system. Improved convex surfaces, annular flow reversal grooves, flow deflection blocks and rough, machined surfaces cooperate to enhance the performance of the labyrinth seal systems. For some labyrinth seal systems a mid-cavity throttle and either rigid teeth or flexible spring teeth may be included.

Surface capillary currents: Rediscovery of fluid-structure interaction by forced evolving boundary theory

NASA Astrophysics Data System (ADS)

Wang, Chunbai; Mitra, Ambar K.

2016-01-01

Any boundary surface evolving in viscous fluid is driven with surface capillary currents. By step function defined for the fluid-structure interface, surface currents are found near a flat wall in a logarithmic form. The general flat-plate boundary layer is demonstrated through the interface kinematics. The dynamics analysis elucidates the relationship of the surface currents with the adhering region as well as the no-slip boundary condition. The wall skin friction coefficient, displacement thickness, and the logarithmic velocity-defect law of the smooth flat-plate boundary-layer flow are derived with the advent of the forced evolving boundary method. This fundamental theory has wide applications in applied science and engineering.

A distributed analysis and visualization system for model and observational data

NASA Technical Reports Server (NTRS)

Wilhelmson, Robert B.

1994-01-01

Software was developed with NASA support to aid in the analysis and display of the massive amounts of data generated from satellites, observational field programs, and from model simulations. This software was developed in the context of the PATHFINDER (Probing ATmospHeric Flows in an Interactive and Distributed EnviRonment) Project. The overall aim of this project is to create a flexible, modular, and distributed environment for data handling, modeling simulations, data analysis, and visualization of atmospheric and fluid flows. Software completed with NASA support includes GEMPAK analysis, data handling, and display modules for which collaborators at NASA had primary responsibility, and prototype software modules for three-dimensional interactive and distributed control and display as well as data handling, for which NSCA was responsible. Overall process control was handled through a scientific and visualization application builder from Silicon Graphics known as the Iris Explorer. In addition, the GEMPAK related work (GEMVIS) was also ported to the Advanced Visualization System (AVS) application builder. Many modules were developed to enhance those already available in Iris Explorer including HDF file support, improved visualization and display, simple lattice math, and the handling of metadata through development of a new grid datatype. Complete source and runtime binaries along with on-line documentation is available via the World Wide Web at: http://redrock.ncsa.uiuc.edu/ PATHFINDER/pathre12/top/top.html.

Application research of 3D additive manufacturing technology in the nail shell

NASA Astrophysics Data System (ADS)

Xiao, Shanhua; Yan, Ruiqiang; Song, Ning

2018-04-01

Based on the analysis of hierarchical slicing algorithm, 3D scanning of enterprise product nailing handle case file is carried out, point cloud data processing is performed on the source file, and the surface modeling and innovative design of nail handling handle case are completed. Using MakerBot Replicator2X-based 3D printer for layered 3D print samples, for the new nail product development to provide reverse modeling and rapid prototyping technical support.

Flow accelerated organic coating degradation

NASA Astrophysics Data System (ADS)

Zhou, Qixin

Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as well as promotes the migration of coating materials from the coating into the working fluid, where coatings experience more severe deterioration in their barrier property under flowing conditions. Pure water has shown to be a much more aggressive working fluid than electrolyte solutions. The flowing fluid over the coating surface could be used as an effective acceleration method.

Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

NASA Astrophysics Data System (ADS)

Davtyan, D.; Machluf, S.; Soudijn, M. L.; Naber, J. B.; van Druten, N. J.; van Linden van den Heuvell, H. B.; Spreeuw, R. J. C.

2018-02-01

Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than 0.2 V /cm at 78 μ m from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.

Development of EUV mask handling technology at MIRAI-Selete

NASA Astrophysics Data System (ADS)

Ota, Kazuya; Amemiya, Mitsuaki; Taguchi, Takao; Kamono, Takashi; Kubo, Hiroyoshi; Takikawa, Tadahiko; Usui, Yoichi; Suga, Osamu

2007-03-01

We, MIRAI-Selete, started a new EUV mask program in April, 2006. Development of EUV mask handling technology is one of the key areas of the program. We plan to develop mask handling technology and to evaluate EUV mask carriers using Lasertec M3350, a particle inspection tool with the defect sensitivity less than 50nm PSL, and Mask Protection Engineering Tool (named "MPE Tool"). M3350 is a newly developed tool based on a conventional M1350 for EUV blanks inspection. Since our M3350 has a blank flipping mechanism in it, we can inspect the front and the back surface of the blank automatically. We plan to use the M3350 for evaluating particle adders during mask shipping, storage and handling. MPE Tool is a special tool exclusively developed for demonstration of pellicleless mask handling. It can handle a mask within a protective enclosure, which Canon and Nikon have been jointly proposing1, and also, can be modified to handle other type of carrier as the need arises.

Thermal Analysis of Cryogenic Hydrogen Liquid Separator

NASA Technical Reports Server (NTRS)

Congiardo, Jared F.; Fortier, Craig R. (Editor)

2014-01-01

During launch for the new Space Launch System (SLS) liquid hydrogen is bleed through the engines during replenish, pre-press, and extended pre-press to condition the engines prior to launch. The predicted bleed flow rates are larger than for the shuttle program. A consequence of the increased flow rates is having liquif hydrogen in the vent system, which the facilities was never designed to handle. To remedy the problem a liquid separator is being designed in the system to accumulated the liquid propellant and protect the facility flare stack (which can only handle gas). The attached document is a presentation of the current thermalfluid analysis performed for the separator and will be presented at the Thermal and Fluid Analysis Workshop (NASA workshop) next week in Cleveland, Ohio.

Electronic publishing and information handling: Plenty of roses, but also some thorns

NASA Astrophysics Data System (ADS)

Heck, André

The current dramatic evolution in information technology is bringing major modifications in the way scientists communicate. The concept of 'electronic publishing' is too restrictive and has often different, sometimes conflicting, interpretations. It is giving way to the broader notion of 'electronic information handling' encompassing the diverse types of information, the different media, as well as the various communication methodologies and technologies. New problems and challenges result also from this new information culture, especially on legal, ethical, and educational grounds. The procedures for validating 'published material' and for evaluating scientific activities will have to be adjusted too. 'Fluid' information is becoming an omnipresent reality. Electronic publishing cannot be conceived without link to knowledge bases and information resources, nor without intelligent information retrieval tools.

Curved film cooling admission tube

NASA Astrophysics Data System (ADS)

Graham, R. W.; Papell, S. S.

1980-10-01

Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

Curved film cooling admission tube

NASA Technical Reports Server (NTRS)

Graham, R. W.; Papell, S. S. (Inventor)

1980-01-01

Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

Grid generation on trimmed Bezier and NURBS quilted surfaces

NASA Technical Reports Server (NTRS)

Woan, Chung-Jin; Clever, Willard C.; Tam, Clement K.

1995-01-01

This paper presents some recently added capabilities to RAGGS, Rockwell Automated Grid Generation System. Included are the trimmed surface handling and display capability and structures and unstructured grid generation on trimmed Bezier and NURBS (non-uniform rational B-spline surfaces) quilted surfaces. Samples are given to demonstrate the new capabilities.

Droplet-surface Impingement Dynamics for Intelligent Spray Design

NASA Technical Reports Server (NTRS)

VanderWal, Randy L.; Kizito, John P.; Tryggvason, Gretar; Berger, Gordon M.; Mozes, Steven D.

2004-01-01

Spray cooling has high potential in thermal management and life support systems by overcoming the deleterious effect of microgravity upon two-phase heat transfer. In particular spray cooling offers several advantages in heat flux removal that include the following: 1. By maintaining a wetted surface, spray droplets impinge upon a thin fluid film rather than a dry solid surface 2. Most heat transfer surfaces will not be smooth but rough. Roughness can enhance conductive cooling, aid liquid removal by flow channeling. 3. Spray momentum can be used to a) substitute for gravity delivering fluid to the surface, b) prevent local dryout and potential thermal runaway and c) facilitate liquid and vapor removal. Yet high momentum results in high We and Re numbers characterizing the individual spray droplets. Beyond an impingement threshold, droplets splash rather than spread. Heat flux declines and spray cooling efficiency can markedly decrease. Accordingly we are investigating droplet impingement upon a) dry solid surfaces, b) fluid films, c) rough surfaces and determining splashing thresholds and relationships for both dry surfaces and those covered by fluid films. We are presently developing engineering correlations delineating the boundary between splashing and non-splashing regions.

Heat Transfer Enhancement During Water and Hydrocarbon Condensation on Lubricant Infused Surfaces.

PubMed

Preston, Daniel J; Lu, Zhengmao; Song, Youngsup; Zhao, Yajing; Wilke, Kyle L; Antao, Dion S; Louis, Marcel; Wang, Evelyn N

2018-01-11

Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Dropwise condensation, where discrete droplets form on the condenser surface, offers a potential improvement in heat transfer of up to an order of magnitude compared to filmwise condensation, where a liquid film covers the surface. Low surface tension fluid condensates such as hydrocarbons pose a unique challenge since typical hydrophobic condenser coatings used to promote dropwise condensation of water often do not repel fluids with lower surface tensions. Recent work has shown that lubricant infused surfaces (LIS) can promote droplet formation of hydrocarbons. In this work, we confirm the effectiveness of LIS in promoting dropwise condensation by providing experimental measurements of heat transfer performance during hydrocarbon condensation on a LIS, which enhances heat transfer by ≈450% compared to an uncoated surface. We also explored improvement through removal of noncondensable gases and highlighted a failure mechanism whereby shedding droplets depleted the lubricant over time. Enhanced condensation heat transfer for low surface tension fluids on LIS presents the opportunity for significant energy savings in natural gas processing as well as improvements in thermal management, heating and cooling, and power generation.

Fundamentals of fluid sealing

NASA Technical Reports Server (NTRS)

Zuk, J.

1976-01-01

The fundamentals of fluid sealing, including seal operating regimes, are discussed and the general fluid-flow equations for fluid sealing are developed. Seal performance parameters such as leakage and power loss are presented. Included in the discussion are the effects of geometry, surface deformations, rotation, and both laminar and turbulent flows. The concept of pressure balancing is presented, as are differences between liquid and gas sealing. Mechanisms of seal surface separation, fundamental friction and wear concepts applicable to seals, seal materials, and pressure-velocity (PV) criteria are discussed.

Electroosmosis of viscoelastic fluids over charge modulated surfaces in narrow confinements

NASA Astrophysics Data System (ADS)

Ghosh, Uddipta; Chakraborty, Suman

2015-06-01

In the present work, we attempt to analyze the electroosmotic flow of a viscoelastic fluid, following quasi-linear constitutive behavior, over charge modulated surfaces in narrow confinements. We obtain analytical solutions for the flow field for thin electrical double layer (EDL) limit through asymptotic analysis for small Deborah numbers. We show that a combination of matched and regular asymptotic expansion is needed for the thin EDL limit. We subsequently determine the modified Smoluchowski slip velocity for viscoelastic fluids and show that the quasi-linear nature of the constitutive behavior adds to the periodicity of the flow. We also obtain the net throughput in the channel and demonstrate its relative decrement as compared to that of a Newtonian fluid. Our results may have potential implications towards augmenting microfluidic mixing by exploiting electrokinetic transport of viscoelastic fluids over charge modulated surfaces.

Pin stack array for thermoacoustic energy conversion

DOEpatents

Keolian, Robert M.; Swift, Gregory W.

1995-01-01

A thermoacoustic stack for connecting two heat exchangers in a thermoacoustic energy converter provides a convex fluid-solid interface in a plane perpendicular to an axis for acoustic oscillation of fluid between the two heat exchangers. The convex surfaces increase the ratio of the fluid volume in the effective thermoacoustic volume that is displaced from the convex surface to the fluid volume that is adjacent the surface within which viscous energy losses occur. Increasing the volume ratio results in an increase in the ratio of transferred thermal energy to viscous energy losses, with a concomitant increase in operating efficiency of the thermoacoustic converter. The convex surfaces may be easily provided by a pin array having elements arranged parallel to the direction of acoustic oscillations and with effective radial dimensions much smaller than the thicknesses of the viscous energy loss and thermoacoustic energy transfer volumes.

Spiral groove seal. [for rotating shaft

NASA Technical Reports Server (NTRS)

Ludwig, L. P.; Strom, T. N. (Inventor)

1974-01-01

Mating flat surfaces inhibit leakage of a fluid around a stationary shaft. A spiral groove produces a pumping action toward the fluid when the shaft rotates. This prevents leakage while a generated hydraulic lifting force separates the mating surfaces to minimize wear. Provision is made for placing these spiral grooves in communication with the fluid to accelerate the generation of the hydraulic lifting force.

The fluid property dependency on micro-fluidic characteristics in the deposition process for microfabrication.

PubMed

Chau, S W; Hsu, K L; Chen, S C; Liou, T M; Shih, K C

2004-07-30

The droplet impingement into a cavity at micrometer-scale is one of important fluidic issues for microfabrications, e.g. the inkjet deposition process in the PLED display manufacturing. The related micro-fluidic behaviors in the deposition process should be carefully treated to ensure the desired quality of microfabrication. The droplets generally dispensing from an inkjet head, which contains an array of nozzles, have a volume in several picoliters, while each nozzle responds very quickly and jets the droplets into cavities on substrates with micrometer size. The nature of droplet impingement depends on the fluid properties, the initial state of droplet, the impact parameters and the surface characteristics. The commonly chosen non-dimensional numbers to describe this process are the Weber number, the Reynolds number, the Ohnesorge number, and the Bond number. This paper discusses the influences of fluid properties of a Newtonian fluid, such as surface tension and fluid viscosity, on micro-fluidic characteristics for a certain jetting speed in the deposition process via a numerical approach, which indicates the impingement process consists of four different phases. In the first phase, the droplet stretching outwards rapidly, where inertia force is dominated. In the second phase, the recoiling of droplet is observed, where surface tension becomes the most important force. In the third phase, the gravitational force pulls the droplet surface towards cavity walls. The fourth phase begins when the droplet surface touches cavity walls and ends when the droplet obtains a stable shape. If the fluid viscosity is relatively small, the droplet surface touches cavity walls in the second phase. A stable fluid layer would not form if the viscosity is relatively small.

Translational and rotational diffusion of Janus nanoparticles at liquid interfaces

NASA Astrophysics Data System (ADS)

Rezvantalab, Hossein; Shojaei-Zadeh, Shahab

2014-11-01

We use molecular dynamics simulations to understand the thermal motion of nanometer-sized Janus particles at the interface between two immiscible fluids. We consider spherical nanoparticles composed of two sides with different affinity to fluid phases, and evaluate their dynamics and changes in fluid structure as a function of particle size and surface chemistry. We show that as the amphiphilicity increases upon enhancing the wetting of each side with its favored fluid, the in-plane diffusivity at the interface becomes slower. Detail analysis of the fluid structure reveals that this is mainly due to formation of a denser adsorption layer around more amphiphilic particles, which leads to increased drag acting against nanoparticle motion. Similarly, the rotational thermal motion of Janus particles is reduced compared to their homogeneous counterparts as a result of the higher resistance of neighboring fluid species against rotation. We also incorporate the influence of fluid density and surface tension on the interfacial dynamics of such Janus nanoparticles. Our findings may have implications in understanding the adsorption mechanism of drugs and protein molecules with anisotropic surface properties to biological interfaces including cell membranes.

Interfacial gauge methods for incompressible fluid dynamics

DOE PAGES

Saye, R.

2016-06-10

Designing numerical methods for incompressible fluid flow involving moving interfaces, for example, in the computational modeling of bubble dynamics, swimming organisms, or surface waves, presents challenges due to the coupling of interfacial forces with incompressibility constraints. A class of methods, denoted interfacial gauge methods, is introduced for computing solutions to the corresponding incompressible Navier-Stokes equations. These methods use a type of "gauge freedom" to reduce the numerical coupling between fluid velocity, pressure, and interface position, allowing high-order accurate numerical methods to be developed more easily. Making use of an implicit mesh discontinuous Galerkin framework, developed in tandem with this work,more » high-order results are demonstrated, including surface tension dynamics in which fluid velocity, pressure, and interface geometry are computed with fourth-order spatial accuracy in the maximum norm. Applications are demonstrated with two-phase fluid flow displaying fine-scaled capillary wave dynamics, rigid body fluid-structure interaction, and a fluid-jet free surface flow problem exhibiting vortex shedding induced by a type of Plateau-Rayleigh instability. The developed methods can be generalized to other types of interfacial flow and facilitate precise computation of complex fluid interface phenomena.« less

SE-FIT

NASA Technical Reports Server (NTRS)

Chen, Yongkang; Weislogel, Mark; Schaeffer, Ben; Semerjian, Ben; Yang, Lihong; Zimmerli, Gregory

2012-01-01

The mathematical theory of capillary surfaces has developed steadily over the centuries, but it was not until the last few decades that new technologies have put a more urgent demand on a substantially more qualitative and quantitative understanding of phenomena relating to capillarity in general. So far, the new theory development successfully predicts the behavior of capillary surfaces for special cases. However, an efficient quantitative mathematical prediction of capillary phenomena related to the shape and stability of geometrically complex equilibrium capillary surfaces remains a significant challenge. As one of many numerical tools, the open-source Surface Evolver (SE) algorithm has played an important role over the last two decades. The current effort was undertaken to provide a front-end to enhance the accessibility of SE for the purposes of design and analysis. Like SE, the new code is open-source and will remain under development for the foreseeable future. The ultimate goal of the current Surface Evolver Fluid Interface Tool (SEFIT) development is to build a fully integrated front-end with a set of graphical user interface (GUI) elements. Such a front-end enables the access to functionalities that are developed along with the GUIs to deal with pre-processing, convergence computation operation, and post-processing. In other words, SE-FIT is not just a GUI front-end, but an integrated environment that can perform sophisticated computational tasks, e.g. importing industry standard file formats and employing parameter sweep functions, which are both lacking in SE, and require minimal interaction by the user. These functions are created using a mixture of Visual Basic and the SE script language. These form the foundation for a high-performance front-end that substantially simplifies use without sacrificing the proven capabilities of SE. The real power of SE-FIT lies in its automated pre-processing, pre-defined geometries, convergence computation operation, computational diagnostic tools, and crash-handling capabilities to sustain extensive computations. SE-FIT performance is enabled by its so-called file-layer mechanism. During the early stages of SE-FIT development, it became necessary to modify the original SE code to enable capabilities required for an enhanced and synchronized communication. To this end, a file-layer was created that serves as a command buffer to ensure a continuous and sequential execution of commands sent from the front-end to SE. It also establishes a proper means for handling crashes. The file layer logs input commands and SE output; it also supports user interruption requests, back and forward operation (i.e. undo and redo), and others. It especially enables the batch mode computation of a series of equilibrium surfaces and the searching of critical parameter values in studying the stability of capillary surfaces. In this way, the modified SE significantly extends the capabilities of the original SE.

Surface-texture evolution of different chemical-vapor-deposited zinc sulfide flats polished with various magnetorheological fluids

DOE PAGES

Salzman, S.; Romanofsky, H. J.; Jacobs, S. D.; ...

2015-08-19

The macro-structure of chemical-vapor-deposited (CVD) zinc sulfide (ZnS) substrates is characterizedby cone-like structures that start growing at the early stages of deposition. As deposition progresses,these cones grow larger and reach centimeter size in height and millimeter size in width. It is challengingto polish out these features from the top layer, particularly for the magnetorheological finishing (MRF)process. A conventional MR fluid tends to leave submillimeter surface artifacts on the finished surface,which is a direct result of the cone-like structure. Here we describe the MRF process of polishing four CVD ZnS substrates, manufactured by four differentvendors, with conventional MR fluid at pHmore » 10 and zirconia-coated-CI (carbonyl iron) MR fluids at pH 4, 5,and 6. We report on the surface–texture evolution of the substrates as they were MRF polished with thedifferent fluids. We show that performances of the zirconia-coated-CI MR fluid at pH 4 are significantlyhigher than that of the same fluid at pH levels of 5 and 6 and moderately higher than that of a conventionalMR fluid at pH 10. An improvement in surface–texture variability from part to part was also observedwith the pH 4 MR fluid.« less

Particles at fluid-fluid interfaces: A new Navier-Stokes-Cahn-Hilliard surface- phase-field-crystal model.

PubMed

Aland, Sebastian; Lowengrub, John; Voigt, Axel

2012-10-01

Colloid particles that are partially wetted by two immiscible fluids can become confined to fluid-fluid interfaces. At sufficiently high volume fractions, the colloids may jam and the interface may crystallize. The fluids together with the interfacial colloids form an emulsion with interesting material properties and offer an important route to new soft materials. A promising approach to simulate these emulsions was presented in Aland et al. [Phys. Fluids 23, 062103 (2011)], where a Navier-Stokes-Cahn-Hilliard model for the macroscopic two-phase fluid system was combined with a surface phase-field-crystal model for the microscopic colloidal particles along the interface. Unfortunately this model leads to spurious velocities which require very fine spatial and temporal resolutions to accurately and stably simulate. In this paper we develop an improved Navier-Stokes-Cahn-Hilliard-surface phase-field-crystal model based on the principles of mass conservation and thermodynamic consistency. To validate our approach, we derive a sharp interface model and show agreement with the improved diffuse interface model. Using simple flow configurations, we show that the new model has much better properties and does not lead to spurious velocities. Finally, we demonstrate the solid-like behavior of the crystallized interface by simulating the fall of a solid ball through a colloid-laden multiphase fluid.

Modular robot

DOEpatents

Ferrante, T.A.

1997-11-11

A modular robot may comprise a main body having a structure defined by a plurality of stackable modules. The stackable modules may comprise a manifold, a valve module, and a control module. The manifold may comprise a top surface and a bottom surface having a plurality of fluid passages contained therein, at least one of the plurality of fluid passages terminating in a valve port located on the bottom surface of the manifold. The valve module is removably connected to the manifold and selectively fluidically connects the plurality of fluid passages contained in the manifold to a supply of pressurized fluid and to a vent. The control module is removably connected to the valve module and actuates the valve module to selectively control a flow of pressurized fluid through different ones of the plurality of fluid passages in the manifold. The manifold, valve module, and control module are mounted together in a sandwich-like manner and comprise a main body. A plurality of leg assemblies are removably connected to the main body and are removably fluidically connected to the fluid passages in the manifold so that each of the leg assemblies can be selectively actuated by the flow of pressurized fluid in different ones of the plurality of fluid passages in the manifold. 12 figs.

Waste Water Treatment Apparatus and Methods

NASA Technical Reports Server (NTRS)

Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor); Littman, Howard (Inventor)

2014-01-01

An improved draft tube spout fluid bed (DTSFB) mixing, handling, conveying, and treating apparatus and systems, and methods for operating are provided. The apparatus and systems can accept particulate material and pneumatically or hydraulically conveying the material to mix and/or treat the material. In addition to conveying apparatus, a collection and separation apparatus adapted to receive the conveyed particulate material is also provided. The collection apparatus may include an impaction plate against which the conveyed material is directed to improve mixing and/or treatment. The improved apparatus are characterized by means of controlling the operation of the pneumatic or hydraulic transfer to enhance the mixing and/or reacting by controlling the flow of fluids, for example, air, into and out of the apparatus. The disclosed apparatus may be used to mix particulate material, for example, mortar; react fluids with particulate material; coat particulate material, or simply convey particulate material.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sierra Thermal/Fluid Team

SIERRA/Aero is a compressible fluid dynamics program intended to solve a wide variety compressible fluid flows including transonic and hypersonic problems. This document describes the commands for assembling a fluid model for analysis with this module, henceforth referred to simply as Aero for brevity. Aero is an application developed using the SIERRA Toolkit (STK). The intent of STK is to provide a set of tools for handling common tasks that programmers encounter when developing a code for numerical simulation. For example, components of STK provide field allocation and management, and parallel input/output of field and mesh data. These services alsomore » allow the development of coupled mechanics analysis software for a massively parallel computing environment. In the definitions of the commands that follow, the term Real_Max denotes the largest floating point value that can be represented on a given computer. Int_Max is the largest such integer value.« less

Electrochemical Orbital Energy Storage (ECOES) technology program. [regenerative fuel cell system

NASA Technical Reports Server (NTRS)

Mcbryar, H.

1980-01-01

The versatility and flexibility of a regenerative fuel cell power and energy storage system is considered. The principal elements of a Regenerative Fuel Cell System combine the fuel cell and electrolysis cell with a photovoltaic solar cell array, along with fluid storage and transfer equipment. The power output of the array (for LEO) must be roughly triple the load requirements of the vehicle since the electrolyzers must receive about double the fuel cell output power in order to regenerate the reactants (2/3 of the array power) while 1/3 of the array power supplies the vehicle base load. The working fluids are essentially recycled indefinitely. Any resupply requirements necessitated by leakage or inefficient reclamation is water - an ideal material to handle and transport. Any variation in energy storage capacity impacts only the fluid storage portion, and the system is insensitive to use of reserve reactant capacity.

Milestone Deliverable: FY18-Q1: Deploy production sliding mesh capability with linear solver benchmarking.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Domino, Stefan P.

2017-12-01

This milestone was focused on deploying and verifying a “sliding-mesh interface,” and establishing baseline timings for blade-resolved simulations of a sub-MW-scale turbine. In the ExaWind project, we are developing both sliding-mesh and overset-mesh approaches for handling the rotating blades in an operating wind turbine. In the sliding-mesh approach, the turbine rotor and its immediate surrounding fluid are captured in a “disk” that is embedded in the larger fluid domain. The embedded fluid is simulated in a coordinate system that rotates with the rotor. It is important that the coupling algorithm (and its implementation) between the rotating and inertial discrete modelsmore » maintains the accuracy of the numerical methods on either side of the interface, i.e., the interface is “design order.”« less

Free Surface Flows and Extensional Rheology of Polymer Solutions

NASA Astrophysics Data System (ADS)

Dinic, Jelena; Jimenez, Leidy Nallely; Biagioli, Madeleine; Estrada, Alexandro; Sharma, Vivek

Free-surface flows - jetting, spraying, atomization during fuel injection, roller-coating, gravure printing, several microfluidic drop/particle formation techniques, and screen-printing - all involve the formation of axisymmetric fluid elements that spontaneously break into droplets by a surface-tension-driven instability. The growth of the capillary-driven instability and pinch-off dynamics are dictated by a complex interplay of inertial, viscous and capillary stresses for simple fluids. Additional contributions by elasticity, extensibility and extensional viscosity play a role for complex fluids. We show that visualization and analysis of capillary-driven thinning and pinch-off dynamics of the columnar neck in an asymmetric liquid bridge created by dripping-onto-substrate (DoS) can be used for characterizing the extensional rheology of complex fluids. Using a wide variety of complex fluids, we show the measurement of the extensional relaxation time, extensional viscosity, power-law index and shear viscosity. Lastly, we elucidate how polymer composition, flexibility, and molecular weight determine the thinning and pinch-off dynamics of polymeric complex fluids.

Analysis of cannabis in oral fluid specimens by GC-MS with automatic SPE.

PubMed

Choi, Hyeyoung; Baeck, Seungkyung; Kim, Eunmi; Lee, Sooyeun; Jang, Moonhee; Lee, Juseon; Choi, Hwakyung; Chung, Heesun

2009-12-01

Methamphetamine (MA) is the most commonly abused drug in Korea, followed by cannabis. Traditionally, MA analysis is carried out on both urine and hair samples and cannabis analysis in urine samples only. Despite the fact that oral fluid has become increasingly popular as an alternative specimen in the field of driving under the influence of drugs (DUID) and work place drug testing, its application has not been expanded to drug analysis in Korea. Oral fluid is easy to collect and handle and can provide an indication of recent drug abuse. In this study, we present an analytical method using GC-MS to determine tetrahydrocannabinol (THC) and its main metabolite 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in oral fluid. The validated method was applied to oral fluid samples collected from drug abuse suspects and the results were compared with those in urine. The stability of THC and THC-COOH in oral fluid stored in different containers was also investigated. Oral fluid specimens from 12 drug abuse suspects, submitted by the police, were collected by direct expectoration. The samples were screened with microplate ELISA. For confirmation they were extracted using automated SPE with mixed-mode cation exchange cartridge, derivatized and analyzed by GC-MS using selective ion monitoring (SIM). The concentrations ofTHC and THC-COOH in oral fluid showed a large variation and the results from oral fluid and urine samples from cannabis abusers did not show any correlation. Thus, detailed information about time interval between drug use and sample collection is needed to interpret the oral fluid results properly. In addition, further investigation about the detection time window ofTHC and THC-COOH in oral fluid is required to substitute oral fluid for urine in drug testing.

Fluid Film Bearing Code Development

NASA Technical Reports Server (NTRS)

1995-01-01

The next generation of rocket engine turbopumps is being developed by industry through Government-directed contracts. These turbopumps will use fluid film bearings because they eliminate the life and shaft-speed limitations of rolling-element bearings, increase turbopump design flexibility, and reduce the need for turbopump overhauls and maintenance. The design of the fluid film bearings for these turbopumps, however, requires sophisticated analysis tools to model the complex physical behavior characteristic of fluid film bearings operating at high speeds with low viscosity fluids. State-of-the-art analysis and design tools are being developed at the Texas A&M University under a grant guided by the NASA Lewis Research Center. The latest version of the code, HYDROFLEXT, is a thermohydrodynamic bulk flow analysis with fluid compressibility, full inertia, and fully developed turbulence models. It can predict the static and dynamic force response of rigid and flexible pad hydrodynamic bearings and of rigid and tilting pad hydrostatic bearings. The Texas A&M code is a comprehensive analysis tool, incorporating key fluid phenomenon pertinent to bearings that operate at high speeds with low-viscosity fluids typical of those used in rocket engine turbopumps. Specifically, the energy equation was implemented into the code to enable fluid properties to vary with temperature and pressure. This is particularly important for cryogenic fluids because their properties are sensitive to temperature as well as pressure. As shown in the figure, predicted bearing mass flow rates vary significantly depending on the fluid model used. Because cryogens are semicompressible fluids and the bearing dynamic characteristics are highly sensitive to fluid compressibility, fluid compressibility effects are also modeled. The code contains fluid properties for liquid hydrogen, liquid oxygen, and liquid nitrogen as well as for water and air. Other fluids can be handled by the code provided that the user inputs information that relates the fluid transport properties to the temperature.

Personnel emergency carrier vehicle

NASA Technical Reports Server (NTRS)

Owens, Lester J. (Inventor); Fedor, Otto H. (Inventor)

1987-01-01

A personnel emergency carrier vehicle is disclosed which includes a vehicle frame supported on steerable front wheels and driven rear wheels. A supply of breathing air is connected to quick connect face mask coupling and umbilical cord couplings for supplying breathing air to an injured worker or attendant either with or without a self-contained atmospheric protection suit for protection against hazardous gases at an accident site. A non-sparking hydraulic motion is utilized to drive the vehicle and suitable direction and throttling controls are provided for controlling the delivery of a hydraulic driving fluid from a pressurized hydraulic fluid accumulator. A steering axis is steerable through a handle to steer the front wheels through a linkage assembly.

Handling, storage, and preparation of human tissues.

PubMed

Dressler, L G; Visscher, D

2001-05-01

Human tissue for flow cytometry must be prepared as an adequate single-cell suspension. The appropriate methods for tissue collection, transport, storage, and dissociation depend on the cell parameters being measured and the localization of the markers. This unit includes a general method for collecting and transporting human tissue and preparing a tissue imprint. Protocols are supplied for tissue disaggregation by either mechanical or enzymatic means and for preparation of single-cell suspensions of whole cells from fine-needle aspirates, pleural effusions, abdominal fluids, or other body fluids. Other protocols detail preparation of intact nuclei from fresh, frozen, or paraffin-embedded tissue. Support protocols cover fixation, cryospin preparation, cryopreservation, and removal of debris.

Theoretical fluid dynamics

NASA Astrophysics Data System (ADS)

Shivamoggi, B. K.

This book is concerned with a discussion of the dynamical behavior of a fluid, and is addressed primarily to graduate students and researchers in theoretical physics and applied mathematics. A review of basic concepts and equations of fluid dynamics is presented, taking into account a fluid model of systems, the objective of fluid dynamics, the fluid state, description of the flow field, volume forces and surface forces, relative motion near a point, stress-strain relation, equations of fluid flows, surface tension, and a program for analysis of the governing equations. The dynamics of incompressible fluid flows is considered along with the dynamics of compressible fluid flows, the dynamics of viscous fluid flows, hydrodynamic stability, and dynamics of turbulence. Attention is given to the complex-variable method, three-dimensional irrotational flows, vortex flows, rotating flows, water waves, applications to aerodynamics, shock waves, potential flows, the hodograph method, flows at low and high Reynolds numbers, the Jeffrey-Hamel flow, and the capillary instability of a liquid jet.

Development of a high-performance boiling heat exchanger by improved liquid supply to narrow channels.

PubMed

Ohta, Haruhiko; Ohno, Toshiyuki; Hioki, Fumiaki; Shinmoto, Yasuhisa

2004-11-01

A two-phase flow loop is a promising method for application to thermal management systems for large-scale space platforms handling large amounts of energy. Boiling heat transfer reduces the size and weight of cold plates. The transportation of latent heat reduces the mass flow rate of working fluid and pump power. To develop compact heat exchangers for the removal of waste heat from electronic devices with high heat generation density, experiments on a method to increase the critical heat flux for a narrow heated channel between parallel heated and unheated plates were conducted. Fine grooves are machined on the heating surface in a transverse direction to the flow and liquid is supplied underneath flattened bubbles by the capillary pressure difference from auxiliary liquid channels separated by porous metal plates from the main heated channel. The critical heat flux values for the present heated channel structure are more than twice those for a flat surface at gap sizes 2 mm and 0.7 mm. The validity of the present structure with auxiliary liquid channels is confirmed by experiments in which the liquid supply to the grooves is interrupted. The increment in the critical heat flux compared to those for a flat surface takes a maximum value at a certain flow rate of liquid supply to the heated channel. The increment is expected to become larger when the length of the heated channel is increased and/or the gravity level is reduced.

Ancient microbes from halite fluid inclusions: optimized surface sterilization and DNA extraction.

PubMed

Sankaranarayanan, Krithivasan; Timofeeff, Michael N; Spathis, Rita; Lowenstein, Tim K; Lum, J Koji

2011-01-01

Fluid inclusions in evaporite minerals (halite, gypsum, etc.) potentially preserve genetic records of microbial diversity and changing environmental conditions of Earth's hydrosphere for nearly one billion years. Here we describe a robust protocol for surface sterilization and retrieval of DNA from fluid inclusions in halite that, unlike previously published methods, guarantees removal of potentially contaminating surface-bound DNA. The protocol involves microscopic visualization of cell structures, deliberate surface contamination followed by surface sterilization with acid and bleach washes, and DNA extraction using Amicon centrifugal filters. Methods were verified on halite crystals of four different ages from Saline Valley, California (modern, 36 ka, 64 ka, and 150 ka), with retrieval of algal and archaeal DNA, and characterization of the algal community using ITS1 sequences. The protocol we developed opens up new avenues for study of ancient microbial ecosystems in fluid inclusions, understanding microbial evolution across geological time, and investigating the antiquity of life on earth and other parts of the solar system.

Fluid-structure interaction of turbulent boundary layer over a compliant surface

NASA Astrophysics Data System (ADS)

Anantharamu, Sreevatsa; Mahesh, Krishnan

2016-11-01

Turbulent flows induce unsteady loads on surfaces in contact with them, which affect material stresses, surface vibrations and far-field acoustics. We are developing a numerical methodology to study the coupled interaction of a turbulent boundary layer with the underlying surface. The surface is modeled as a linear elastic solid, while the fluid follows the spatially filtered incompressible Navier-Stokes equations. An incompressible Large Eddy Simulation finite volume flow approach based on the algorithm of Mahesh et al. is used in the fluid domain. The discrete kinetic energy conserving property of the method ensures robustness at high Reynolds number. The linear elastic model in the solid domain is integrated in space using finite element method and in time using the Newmark time integration method. The fluid and solid domain solvers are coupled using both weak and strong coupling methods. Details of the algorithm, validation, and relevant results will be presented. This work is supported by NSWCCD, ONR.

Influence of the softness of the parietal pleura on respiratory sliding mechanisms

PubMed Central

Kim, Jae Hun; Butler, James P.; Loring, Stephen H.

2011-01-01

The pleural surfaces of the lung and chest wall slide against each other with low friction. Normal load support can be effected either by a combination of quasi-static fluid pressure and solid-solid contacts of relatively stiff asperities, or by shear-induced hydrodynamic pressures in the pleural fluid layer. To distinguish between these mechanisms, we measured surface topography and spatial distribution of stiffness of rat parietal pleura using atomic force microscopy. The topography of the pleural surface has unevenness at length scales smaller than the thickness of pleural fluid, similar to mesothelial cell diameters. The estimated maximum normal contact pressure that could be borne by asperities of the soft pleura is much less than that required to support a substantial difference between pleural fluid pressure and the pleural surface pressure. These results suggest that during sliding motion, unevenness of the pleural surface is smoothed by local hydrodynamic pressure, preventing any significant contribution of solid-solid contacts. PMID:21473935

Sabkha Trafficability,

DTIC Science & Technology

1981-01-01

Meteorological Parameters at Meteorological Station 1, 31 May 1980 ........................ 68 $24 Relationship of Jubai. Port Datum to Tide Table Datum. .70 25...around which was a circular weight with two handles. Once assembled, the device was nositioned vertically at the point to be sampled and manually...limited use for sampling very fluid or unconsolidated sand or shell. In the former case, the upper few centimeters of cohesive sediment became embedded

Theoretical Calculations on Sediment Transport on Titan, and the Possible Production of Streamlined Forms

NASA Technical Reports Server (NTRS)

Burr, D. M.; Emery, J. P.; Lorenz, R. D.

2005-01-01

The Cassini Imaging Science System (ISS) has been returning images of Titan, along with other Saturnian satellites. Images taken through the 938 nm methane window see down to Titan's surface. One of the purposes of the Cassini mission is to investigate possible fluid cycling on Titan. Lemniscate features shown recently and radar evidence of surface flow prompted us to consider theoretically the creation by methane fluid flow of streamlined forms on Titan. This follows work by other groups in theoretical consideration of fluid motion on Titan's surface.

Ebola Virus Stability on Surfaces and in Fluids in Simulated Outbreak Environments.

PubMed

Fischer, Robert; Judson, Seth; Miazgowicz, Kerri; Bushmaker, Trenton; Prescott, Joseph; Munster, Vincent J

2015-07-01

We evaluated the stability of Ebola virus on surfaces and in fluids under simulated environmental conditions for the climate of West Africa and for climate-controlled hospitals. This virus remains viable for a longer duration on surfaces in hospital conditions than in African conditions and in liquid than in dried blood.

Impact of microstructure evolution on the difference between geometric and reactive surface areas in natural chalk

NASA Astrophysics Data System (ADS)

Yang, Y.; Bruns, S.; Stipp, S. L. S.; Sørensen, H. O.

2018-05-01

The coupling between flow and mineral dissolution drives the evolution of many natural and engineered flow systems. Pore surface changes as microstructure evolves but this transient behaviour has traditionally been difficult to model. We combined a reactor network model with experimental, greyscale tomography data to establish the morphological grounds for differences among geometric, reactive and apparent surface areas in dissolving chalk. This approach allowed us to study the effects of initial geometry and macroscopic flow rate independently. The simulations showed that geometric surface, which represents a form of local transport heterogeneity, increases in an imposed flow field, even when the porous structure is chemically homogeneous. Hence, the fluid-reaction coupling leads to solid channelisation, which further results in fluid focusing and an increase in geometric surface area. Fluid focusing decreases the area of reactive surface and the residence time of reactant, both contribute to the over-normalisation of reaction rate. In addition, the growing and merging of microchannels, near the fluid entrance, contribute to the macroscopic, fast initial dissolution rate of rocks.

Far-Field Noise Induced by Bubble near Free Surface

NASA Astrophysics Data System (ADS)

Ye, Xi; Li, Jiang-tao; Liu, Jian-hua; Chen, Hai-long

2018-03-01

The motion of a bubble near the free surface is solved by the boundary element method based on the linear wave equation, and the influence of fluid compressibility on bubble dynamics is analyzed. Based on the solution of the bubble motion, the far-field radiation noise induced by the bubble is calculated using Kirchhoff moving boundary integral equation, and the influence of free surface on far-field noise is researched. As the results, the oscillation amplitude of the bubble is weakened in compressible fluid compared with that in incompressible fluid, and the free surface amplifies the effect of fluid compressibility. When the distance between the bubble and an observer is much larger than that between the bubble and free surface, the sharp wave trough of the sound pressure at the observer occurs. With the increment of the distance between the bubble and free surface, the time of the wave trough appearing is delayed and the value of the wave trough increase. When the distance between the observer and the bubble is reduced, the sharp wave trough at the observer disappears.

A sampling device with a capped body and detachable handle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jezek, Gerd-Rainer

1997-12-01

The present invention relates to a device for sampling radioactive waste and more particularly to a device for sampling radioactive waste which prevents contamination of a sampled material and the environment surrounding the sampled material. During vitrification of nuclear wastes, it is necessary to remove contamination from the surfaces of canisters filled with radioactive glass. After removal of contamination, a sampling device is used to test the surface of the canister. The one piece sampling device currently in use creates a potential for spreading contamination during vitrification operations. During operations, the one piece sampling device is transferred into and outmore » of the vitrification cell through a transfer drawer. Inside the cell, a remote control device handles the sampling device to wipe the surface of the canister. A one piece sampling device can be contaminated by the remote control device prior to use. Further, the sample device can also contaminate the transfer drawer producing false readings for radioactive material. The present invention overcomes this problem by enclosing the sampling pad in a cap. The removable handle is reused which reduces the amount of waste material.« less

Orbital maneuvering vehicle end effectors

NASA Technical Reports Server (NTRS)

Myers, W. Neill (Inventor); Forbes, John C. (Inventor); Barnes, Wayne L. (Inventor)

1988-01-01

An end effector device (A) for grasping and holding an article such as a handle (18) of a space telescope is disclosed. The device includes a V-shaped capture window (74) defined as inclined surfaces (76, 78) in parallel face plates (22, 24) which converge toward a retainer recess (54) in which the handle is retained. A pivotal finger (30) meshes with a pair of pivoted fingers (26, 28) which rotate in counterrotation. The fingers rotate to pull a handle within the capture window into recess (54) where latches (50) lock handle (18) in the recess. To align the capture window, plates (22, 24) may be cocked plus or minus five degrees on base (64).

Fluid to fluid contact heat exchanger

NASA Technical Reports Server (NTRS)

Clark, W. E.

1986-01-01

Heat transfer and pressure drop test results for a fluid to fluid contact heat exchanger are reported. The heat exchanger, fabricated and tested to demonstrate one method of transferring heat between structures in space, had a total contact area of 0.18 sq m. It utilized contact surfaces which were flexible and conformed to the mating contact surfaces upon pressurization of the fluid circulating within the heat exchanger. During proof-of-concept performance tests, the heat exchanger was operated in a typical earth environment. It demonstrated a contact conductance of 3.8 kW/sq m C at contact pressures in the 15 to 70 kPa range.

Numerical study of soap-film flow by nonuniform alternating electric fields

NASA Astrophysics Data System (ADS)

Nasiri, M.; Shirsavar, R.; Mollaei, S.; Ramos, A.

2017-02-01

Fluid flow of suspended liquid films induced by non-uniform alternating electric fields has been reported. The electric fields were generated by two rod-like electrodes perpendicular to the fluid surface. The observed fluid flow was explained qualitatively by considering a charge induction mechanism, where the electric field actuates on the charge induced on the film surface. In this paper we perform a numerical study of this fluid flow taking into account the charge induction mechanism. The numerical results are compared with experiments and good agreement is found. Finally, we propose the application of the device as a new kind of two dimensional fluid pump.

Numerical study of soap-film flow by nonuniform alternating electric fields.

PubMed

Nasiri, M; Shirsavar, R; Mollaei, S; Ramos, A

2017-02-01

Fluid flow of suspended liquid films induced by non-uniform alternating electric fields has been reported. The electric fields were generated by two rod-like electrodes perpendicular to the fluid surface. The observed fluid flow was explained qualitatively by considering a charge induction mechanism, where the electric field actuates on the charge induced on the film surface. In this paper we perform a numerical study of this fluid flow taking into account the charge induction mechanism. The numerical results are compared with experiments and good agreement is found. Finally, we propose the application of the device as a new kind of two dimensional fluid pump.

Method for noninvasive determination of acoustic properties of fluids inside pipes

DOEpatents

None

2016-08-02

A method for determining the composition of fluids flowing through pipes from noninvasive measurements of acoustic properties of the fluid is described. The method includes exciting a first transducer located on the external surface of the pipe through which the fluid under investigation is flowing, to generate an ultrasound chirp signal, as opposed to conventional pulses. The chirp signal is received by a second transducer disposed on the external surface of the pipe opposing the location of the first transducer, from which the transit time through the fluid is determined and the sound speed of the ultrasound in the fluid is calculated. The composition of a fluid is calculated from the sound speed therein. The fluid density may also be derived from measurements of sound attenuation. Several signal processing approaches are described for extracting the transit time information from the data with the effects of the pipe wall having been subtracted.

The Impact of Solid Surface Features on Fluid-Fluid Interface Configuration

NASA Astrophysics Data System (ADS)

Araujo, J. B.; Brusseau, M. L. L.

2017-12-01

Pore-scale fluid processes in geological media are critical for a broad range of applications such as radioactive waste disposal, carbon sequestration, soil moisture distribution, subsurface pollution, land stability, and oil and gas recovery. The continued improvement of high-resolution image acquisition and processing have provided a means to test the usefulness of theoretical models developed to simulate pore-scale fluid processes, through the direct quantification of interfaces. High-resolution synchrotron X-ray microtomography is used in combination with advanced visualization tools to characterize fluid distributions in natural geologic media. The studies revealed the presence of fluid-fluid interface associated with macroscopic features on the surfaces of the solids such as pits and crevices. These features and respective fluid interfaces, which are not included in current theoretical or computational models, may have a significant impact on accurate simulation and understanding of multi-phase flow, energy, heat and mass transfer processes.

Flow metering valve

DOEpatents

Blaedel, K.L.

1983-11-03

An apparatus for metering fluids at high pressures of about 20,000 to 60,000 psi is disclosed. The apparatus includes first and second plates which are positioned adjacent each other to form a valve chamber. The plates are made of materials which have substantially equal elastic properties. One plate has a planar surface area, and the other a recessed surface area defined by periphery and central lips. When the two plates are positioned in adjacent contacting relationship, a valve chamber is formed between the planar surface area and the recessed surface area. Fluid is introduced into the chamber and exits therefrom when a deformation occurs at positions where they no longer form a valve seat. This permits the metering of fluids at high pressures and at slow variable rates. Fluid then exits from the chamber until an applied external force becomes large enough to bring the valve seats back into contact.

A new model for fluid velocity slip on a solid surface.

PubMed

Shu, Jian-Jun; Teo, Ji Bin Melvin; Chan, Weng Kong

2016-10-12

A general adsorption model is developed to describe the interactions between near-wall fluid molecules and solid surfaces. This model serves as a framework for the theoretical modelling of boundary slip phenomena. Based on this adsorption model, a new general model for the slip velocity of fluids on solid surfaces is introduced. The slip boundary condition at a fluid-solid interface has hitherto been considered separately for gases and liquids. In this paper, we show that the slip velocity in both gases and liquids may originate from dynamical adsorption processes at the interface. A unified analytical model that is valid for both gas-solid and liquid-solid slip boundary conditions is proposed based on surface science theory. The corroboration with the experimental data extracted from the literature shows that the proposed model provides an improved prediction compared to existing analytical models for gases at higher shear rates and close agreement for liquid-solid interfaces in general.

Method and system for providing cooling for turbine components

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morgan, Victor John; Lacy, Benjamin Paul

2016-08-16

A system for providing cooling for a turbine component that includes an outer surface exposed to combustion gases is provided. A component base includes at least one fluid supply passage coupleable to a source of cooling fluid. At least one feed passage communicates with the at least one fluid supply passage. At least one delivery channel communicates with the at least one feed passage. At least one cover layer covers the at least one feed passage and the at least one delivery channel, defining at least in part the component outer surface. At least one discharge passage extends to themore » outer surface. A diffuser section is defined in at least one of the at least one delivery channel and the at least one discharge passage, such that a fluid channeled through the system is diffused prior to discharge adjacent the outer surface.« less

Flow metering valve

DOEpatents

Blaedel, Kenneth L.

1985-01-01

An apparatus for metering fluids at high pressures of about 20,000 to 60,000 psi is disclosed. The apparatus includes first and second plates which are positioned adjacent each other to form a valve chamber. The plates are made of materials which have substantially equal elastic properties. One plate has a planar surface area, and the other a recessed surface area defined by periphery and central lips. When the two plates are positioned in adjacent contacting relationship, a valve chamber is formed between the planar surface area and the recessed surface area. Fluid is introduced into the chamber and exits therefrom when a deformation occurs at positions where they no longer form a valve seat. This permits the metering of fluids at high pressures and at slow variable rates. Fluid then exits from the chamber until an applied external force becomes large enough to bring the valve seats back into contact.

Impact of a complex fluid droplet on wettable and non wettable surfaces

NASA Astrophysics Data System (ADS)

Bolleddula, Daniel; Aliseda, Alberto

2008-11-01

The impact of liquid droplets is a phenomenon prevalent in many natural and industrial processes. Such events include rain drops, fuel injection, and ink-jet printing. To date, research in atomization and droplet impact has been focused on Newtonian fluids. In the coating of pharmaceutical tablets, the coating solutions contain polymers, surfactants, and large concentrations of insoluble solids in suspension which inherently exhibit non-Newtonian behavior. In this work, we will present ongoing droplet impact experiments using complex rheology fluids under a wide range of Weber and Ohnesorge numbers. Both hydrophilic and hydrophobic surfaces are been studied, and the effect of surface roughness has also been considered. We will describe the limits of bouncing, spreading, and splashing for these complex fluids. We will also discuss quantitative information such as spreading rates and contact angle measurements on wettable and non-wettable surfaces obtained from high speed images.

Methods for producing films using supercritical fluid

DOEpatents

Yonker, Clement R.; Fulton, John L.

2004-06-15

A method for forming a continuous film on a substrate surface that involves depositing particles onto a substrate surface and contacting the particle-deposited substrate surface with a supercritical fluid under conditions sufficient for forming a continuous film from the deposited particles. The particles may have a mean particle size of less 1 micron. The method may be performed by providing a pressure vessel that can contain a compressible fluid. A particle-deposited substrate is provided in the pressure vessel and the compressible fluid is maintained at a supercritical or sub-critical state sufficient for forming a film from the deposited particles. The T.sub.g of particles may be reduced by subjecting the particles to the methods detailed in the present disclosure.

Papain incorporated chitin dressings for wound debridement sterilized by gamma radiation

NASA Astrophysics Data System (ADS)

Singh, Durgeshwer; Singh, Rita

2012-11-01

Wound debridement is essential for the removal of necrotic or nonviable tissue from the wound surface to create an environment conducive to healing. Nonsurgical enzymatic debridement is an attractive method due to its effectiveness and ease of use. Papain is a proteolytic enzyme derived from the fruit of Carica papaya and is capable of breaking down a variety of necrotic tissue substrates. The present study was focused on the use of gamma radiation for sterilization of papain dressing with wound debriding activity. Membranes with papain were prepared using 0.5% chitin in lithium chloride/dimethylacetamide solvent and sterilized by gamma radiation. Fluid absorption capacity of chitin-papain membranes without glycerol was 14.30±6.57% in 6 h. Incorporation of glycerol resulted in significant (p<0.001) increase in the absorption capacity. Moisture vapour transmission rate of the membranes was 4285.77±455.61 g/m2/24 h at 24 h. Gamma irradiation at 25 kGy was found suitable for sterilization of the dressings. Infrared (IR) spectral scanning has shown that papain was stable on gamma irradiation at 25-35 kGy. The irradiated chitin-papain membranes were impermeable to different bacterial strains and also exhibited strong bactericidal action against both Gram-positive and Gram-negative bacteria. The fluid handling characteristics and the antimicrobial properties of chitin-papain membranes sterilized by gamma radiation were found suitable for use as wound dressing with debriding activity.

Fluid-structure interaction modeling of clusters of spacecraft parachutes with modified geometric porosity

NASA Astrophysics Data System (ADS)

Takizawa, Kenji; Tezduyar, Tayfun E.; Boben, Joseph; Kostov, Nikolay; Boswell, Cody; Buscher, Austin

2013-12-01

To increase aerodynamic performance, the geometric porosity of a ringsail spacecraft parachute canopy is sometimes increased, beyond the "rings" and "sails" with hundreds of "ring gaps" and "sail slits." This creates extra computational challenges for fluid-structure interaction (FSI) modeling of clusters of such parachutes, beyond those created by the lightness of the canopy structure, geometric complexities of hundreds of gaps and slits, and the contact between the parachutes of the cluster. In FSI computation of parachutes with such "modified geometric porosity," the flow through the "windows" created by the removal of the panels and the wider gaps created by the removal of the sails cannot be accurately modeled with the Homogenized Modeling of Geometric Porosity (HMGP), which was introduced to deal with the hundreds of gaps and slits. The flow needs to be actually resolved. All these computational challenges need to be addressed simultaneously in FSI modeling of clusters of spacecraft parachutes with modified geometric porosity. The core numerical technology is the Stabilized Space-Time FSI (SSTFSI) technique, and the contact between the parachutes is handled with the Surface-Edge-Node Contact Tracking (SENCT) technique. In the computations reported here, in addition to the SSTFSI and SENCT techniques and HMGP, we use the special techniques we have developed for removing the numerical spinning component of the parachute motion and for restoring the mesh integrity without a remesh. We present results for 2- and 3-parachute clusters with two different payload models.

Lunar vertical-shaft mining system

NASA Technical Reports Server (NTRS)

Introne, Steven D. (Editor); Krause, Roy; Williams, Erik; Baskette, Keith; Martich, Frederick; Weaver, Brad; Meve, Jeff; Alexander, Kyle; Dailey, Ron; White, Matt

1994-01-01

This report proposes a method that will allow lunar vertical-shaft mining. Lunar mining allows the exploitation of mineral resources imbedded within the surface. The proposed lunar vertical-shaft mining system is comprised of five subsystems: structure, materials handling, drilling, mining, and planning. The structure provides support for the exploration and mining equipment in the lunar environment. The materials handling subsystem moves mined material outside the structure and mining and drilling equipment inside the structure. The drilling process bores into the surface for the purpose of collecting soil samples, inserting transducer probes, or locating ore deposits. Once the ore deposits are discovered and pinpointed, mining operations bring the ore to the surface. The final subsystem is planning, which involves the construction of the mining structure.

Generation of long subharmonic internal waves by surface waves

NASA Astrophysics Data System (ADS)

Tahvildari, Navid; Kaihatu, James M.; Saric, William S.

2016-10-01

A new set of Boussinesq equations is derived to study the nonlinear interactions between long waves in a two-layer fluid. The fluid layers are assumed to be homogeneous, inviscid, incompressible, and immiscible. Based on the Boussinesq equations, an analytical model is developed using a second-order perturbation theory and applied to examine the transient evolution of a resonant triad composed of a surface wave and two oblique subharmonic internal waves. Wave damping due to weak viscosity in both layers is considered. The Boussinesq equations and the analytical model are verified. In contrast to previous studies which focus on short internal waves, we examine long waves and investigate some previously unexplored characteristics of this class of triad interaction. In viscous fluids, surface wave amplitudes must be larger than a threshold to overcome viscous damping and trigger internal waves. The dependency of this critical amplitude as well as the growth and damping rates of internal waves on important parameters in a two-fluid system, namely the directional angle of the internal waves, depth, density, and viscosity ratio of the fluid layers, and surface wave amplitude and frequency is investigated.

Coherent structures over Super Hydrophobic and Liquid Infused Surfaces

NASA Astrophysics Data System (ADS)

Arenas, Isnardo; Bernardini, Matteo; Leonardi, Stefano

2017-11-01

Numerical Simulations of two superposed fluids in a turbulent channel have been performed. Both walls of the channel are made of longitudinal riblets with a gas fractions of 0.5 and several pitch values p+ = 18 , 36 , 72 , 144 . For Liquid Infused Surfaces, LIS, with a viscosity ratio m =μ1 /μ2 = 0.4 (where the subscripts 1 and 2 indicate the fluid in the cavities and the overlying fluid respectively) two cases have been considered varying the Weber number: We = 0 , implying an interface sustained by the surface tension and We = 1000 with the dynamics of the interface between the two fluids modeled with a Level Set Approach. Results are compared to the case mimicking water over air (Super hydrophobic Surface SHS m = 0.02) and We = 0 . A smooth channel with one fluid only at Reτ = 180 is used as reference and to assess how the LIS and SHS modify coherent structures near the wall. Numerical simulations were performed on XSEDE TACC under Grant CTS070066. This work was supported by ONR MURI Grants N00014-12-01-0875 and N00014-12-01-0962.

Improvement of MRR and surface roughness during electrical discharge machining (EDM) using aluminum oxide powder mixed dielectric fluid

NASA Astrophysics Data System (ADS)

Khan, A. A.; Mohiuddin, A. K. M.; Latif, M. A. A.

2018-01-01

This paper discusses the effect of aluminium oxide (Al203) addition to dielectric fluid during electrical discharge machining (EDM). Aluminium oxide was added to the dielectric used in the EDM process to improve its performance when machining the stainless steel AISI 304, while copper was used as the electrode. Effect of the concentration of Al203 (0.3 mg/L) in dielectric fluid was compared with EDM without any addition of Al203. Surface quality of stainless steel and the material removal rate were investigated. Design of the experiment (DOE) was used for the experimental plan. Statistical analysis was done using ANOVA and then appropriate model was designated. The experimental results show that with dispersing of aluminium oxide in dielectric fluid surface roughness was improved while the material removal rate (MRR) was increased to some extent. These indicate the improvement of EDM performance using aluminium oxide in dielectric fluid. It was also found that with increase in pulse on time both MRR and surface roughness increase sharply.

Particle-bearing currents in uniform density and two-layer fluids

NASA Astrophysics Data System (ADS)

Sutherland, Bruce R.; Gingras, Murray K.; Knudson, Calla; Steverango, Luke; Surma, Christopher

2018-02-01

Lock-release gravity current experiments are performed to examine the evolution of a particle bearing flow that propagates either in a uniform-density fluid or in a two-layer fluid. In all cases, the current is composed of fresh water plus micrometer-scale particles, the ambient fluid is saline, and the current advances initially either over the surface as a hypopycnal current or at the interface of the two-layer fluid as a mesopycnal current. In most cases the tank is tilted so that the ambient fluid becomes deeper with distance from the lock. For hypopycnal currents advancing in a uniform density fluid, the current typically slows as particles rain out of the current. While the loss of particles alone from the current should increase the current's buoyancy and speed, in practice the current's speed decreases because the particles carry with them interstitial fluid from the current. Meanwhile, rather than settling on the sloping bottom of the tank, the particles form a hyperpycnal (turbidity) current that advances until enough particles rain out that the relatively less dense interstitial fluid returns to the surface, carrying some particles back upward. When a hypopycnal current runs over the surface of a two-layer fluid, the particles that rain out temporarily halt their descent as they reach the interface, eventually passing through it and again forming a hyperpycnal current. Dramatically, a mesopycnal current in a two-layer fluid first advances along the interface and then reverses direction as particles rain out below and fresh interstitial fluid rises above.

Using Ozone To Clean and Passivate Oxygen-Handling Hardware

NASA Technical Reports Server (NTRS)

Torrance, Paul; Biesinger, Paul

2009-01-01

A proposed method of cleaning, passivating, and verifying the cleanliness of oxygen-handling hardware would extend the established art of cleaning by use of ozone. As used here, "cleaning" signifies ridding all exposed surfaces of combustible (in particular, carbon-based) contaminants. The method calls for exposing the surfaces of the hardware to ozone while monitoring the ozone effluent for carbon dioxide. The ozone would passivate the hardware while oxidizing carbon-based residues, converting the carbon in them to carbon dioxide. The exposure to ozone would be continued until no more carbon dioxide was detected, signifying that cleaning and passivation were complete.

Modeling of Waves Propagating in Water with a Crushed Ice Layer on the Free Surface

NASA Astrophysics Data System (ADS)

Szmidt, Kazimierz

2017-12-01

A transformation of gravitational waves in fluid of constant depth with a crushed ice layer floating on the free fluid surface is considered. The propagating waves undergo a slight damping along their path of propagation. The main goal of the study is to construct an approximate descriptive model of this phenomenon.With regard to small displacements of the free surface, a viscous type model of damping is considered, which corresponds to a continuous distribution of dash-pots at the free surface of the fluid. A constant parameter of the dampers is assumed in advance as known parameter of damping. This parameter may be obtained by means of experiments in a laboratory flume.

Exact analytical solution to a transient conjugate heat-transfer problem

NASA Technical Reports Server (NTRS)

Sucec, J.

1973-01-01

An exact analytical solution is found for laminar, constant-property, slug flow over a thin plate which is also convectively cooled from below. The solution is found by means of two successive Laplace transformations when a transient in the plate and the fluid is initiated by a step change in the fluid inlet temperature. The exact solution yields the transient fluid temperature, surface heat flux, and surface temperature distributions. The results of the exact transient solution for the surface heat flux are compared to the quasi-steady values, and a criterion for the validity of the quasi-steady results is found. Also the effect of the plate coupling parameter on the surface heat flux are investigated.

Engine having a variable valve actuation system

DOEpatents

Hefler, Gregory W [Chillicothe, IL

2004-10-12

An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

Engine having a variable valve actuation system

DOEpatents

Hefler, Gregory W.

2005-10-12

An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

Microfluidic hubs, systems, and methods for interface fluidic modules

DOEpatents

Bartsch, Michael S; Claudnic, Mark R; Kim, Hanyoup; Patel, Kamlesh D; Renzi, Ronald F; Van De Vreugde, James L

2015-01-27

Embodiments of microfluidic hubs and systems are described that may be used to connect fluidic modules. A space between surfaces may be set by fixtures described herein. In some examples a fixture may set substrate-to-substrate spacing based on a distance between registration surfaces on which the respective substrates rest. Fluidic interfaces are described, including examples where fluid conduits (e.g. capillaries) extend into the fixture to the space between surfaces. Droplets of fluid may be introduced to and/or removed from microfluidic hubs described herein, and fluid actuators may be used to move droplets within the space between surfaces. Continuous flow modules may be integrated with the hubs in some examples.

Rindler fluid with weak momentum relaxation

NASA Astrophysics Data System (ADS)

Khimphun, Sunly; Lee, Bum-Hoon; Park, Chanyong; Zhang, Yun-Long

2018-01-01

We realize the weak momentum relaxation in Rindler fluid, which lives on the time-like cutoff surface in an accelerating frame of flat spacetime. The translational invariance is broken by massless scalar fields with weak strength. Both of the Ward identity and the momentum relaxation rate of Rindler fluid are obtained, with higher order correction in terms of the strength of momentum relaxation. The Rindler fluid with momentum relaxation could also be approached through the near horizon limit of cutoff AdS fluid with momentum relaxation, which lives on a finite time-like cutoff surface in Anti-de Sitter(AdS) spacetime, and further could be connected with the holographic conformal fluid living on AdS boundary at infinity. Thus, in the holographic Wilson renormalization group flow of the fluid/gravity correspondence with momentum relaxation, the Rindler fluid can be considered as the Infrared Radiation(IR) fixed point, and the holographic conformal fluid plays the role of the ultraviolet(UV) fixed point.

Dropping macadamia nuts-in-shell reduces kernel roasting quality.

PubMed

Walton, David A; Wallace, Helen M

2010-10-01

Macadamia nuts ('nuts-in-shell') are subjected to many impacts from dropping during postharvest handling, resulting in damage to the raw kernel. The effect of dropping on roasted kernel quality is unknown. Macadamia nuts-in-shell were dropped in various combinations of moisture content, number of drops and receiving surface in three experiments. After dropping, samples from each treatment and undropped controls were dry oven-roasted for 20 min at 130 °C, and kernels were assessed for colour, mottled colour and surface damage. Dropping nuts-in-shell onto a bed of nuts-in-shell at 3% moisture content or 20% moisture content increased the percentage of dark roasted kernels. Kernels from nuts dropped first at 20%, then 10% moisture content, onto a metal plate had increased mottled colour. Dropping nuts-in-shell at 3% moisture content onto nuts-in-shell significantly increased surface damage. Similarly, surface damage increased for kernels dropped onto a metal plate at 20%, then at 10% moisture content. Postharvest dropping of macadamia nuts-in-shell causes concealed cellular damage to kernels, the effects not evident until roasting. This damage provides the reagents needed for non-enzymatic browning reactions. Improvements in handling, such as reducing the number of drops and improving handling equipment, will reduce cellular damage and after-roast darkening. Copyright © 2010 Society of Chemical Industry.

Kitchen practices used in handling broiler chickens and survival of Campylobacter spp. on cutting surfaces in Kampala, Uganda.

PubMed

Wanyenya, Irene; Muyanja, Charles; Nasinyama, George William

2004-09-01

Cross-contamination during food preparation has been identified as an important factor associated with foodborne illnesses. Handling practices used during preparation of broiler chickens in 31 fast-food restaurants and 86 semisettled street stands (street vendors) were assessed by use of a standard checklist. These establishments used wood, plastic, or metal cutting surfaces during the preparation of broiler chickens. The survival of Campylobacter spp. on kitchen cutting surfaces was determined by inoculating approximately 10(6) CFU of Campylobacter jejuni onto sterile plastic, wooden, and metal cutting boards. The concentrations of the organisms were then assessed in triplicate on each type of cutting board over a 3-h period using standard microbiological methods for thermophilic Campylobacter spp. In 87% of food establishments, the same work area was used for preparation of raw and cooked chicken, and in 68% of these establishments the same cutting boards were used for raw and cooked chicken. None of the establishments applied disinfectants or sanitizers when washing contact surfaces. Campylobacter spp. survived on wooden and plastic but not on metal cutting boards after 3 h of exposure. The handling practices in food preparation areas, therefore, provide an opportunity for cross-contamination of Campylobacter spp. to ready-to-eat foods.

Surface thermodynamics, surface stress, equations at surfaces and triple lines for deformable bodies.

PubMed

Olives, Juan

2010-03-03

The thermodynamics and mechanics of the surface of a deformable body are studied here, following and refining the general approach of Gibbs. It is first shown that the 'local' thermodynamic variables of the state of the surface are only the temperature, the chemical potentials and the surface strain tensor (true thermodynamic variables, for a viscoelastic solid or a viscous fluid). A new definition of the surface stress is given and the corresponding surface thermodynamics equations are presented. The mechanical equilibrium equation at the surface is then obtained. It involves the surface stress and is similar to the Cauchy equation for the volume. Its normal component is a generalization of the Laplace equation. At a (body-fluid-fluid) triple contact line, two equations are obtained, which represent: (i) the equilibrium of the forces (surface stresses) for a triple line fixed on the body; (ii) the equilibrium relative to the motion of the line with respect to the body. This last equation leads to a strong modification of Young's classical capillary equation.

Handling of thermal paper: Implications for dermal exposure to bisphenol A and its alternatives

PubMed Central

Bernier, Meghan R.

2017-01-01

Bisphenol A (BPA) is an endocrine disrupting chemical used in a wide range of consumer products including photoactive dyes used in thermal paper. Recent studies have shown that dermal absorption of BPA can occur when handling these papers. Yet, regulatory agencies have largely dismissed thermal paper as a major source of BPA exposure. Exposure estimates provided by agencies such as the European Food Safety Authority (EFSA) are based on assumptions about how humans interact with this material, stating that ‘typical’ exposures for adults involve only one handling per day for short periods of time (<1 minute), with limited exposure surfaces (three fingertips). The objective of this study was to determine how individuals handle thermal paper in one common setting: a cafeteria providing short-order meals. We observed thermal paper handling in a college-aged population (n = 698 subjects) at the University of Massachusetts’ dining facility. We find that in this setting, individuals handle receipts for an average of 11.5 min, that >30% of individuals hold thermal paper with more than three fingertips, and >60% allow the paper to touch their palm. Only 11% of the participants we observed were consistent with the EFSA model for time of contact and dermal surface area. Mathematical modeling based on handling times we measured and previously published transfer coefficients, concentrations of BPA in paper, and absorption factors indicate the most conservative estimated intake from handling thermal paper in this population is 51.1 ng/kg/day, similar to EFSA’s estimates of 59 ng/kg/day from dermal exposures. Less conservative estimates, using published data on concentrations in thermal paper and transfer rates to skin, indicate that exposures are likely significantly higher. Based on our observational data, we propose that the current models for estimating dermal BPA exposures are not consistent with normal human behavior and should be reevaluated. PMID:28570582

Handling of thermal paper: Implications for dermal exposure to bisphenol A and its alternatives.

PubMed

Bernier, Meghan R; Vandenberg, Laura N

2017-01-01

Bisphenol A (BPA) is an endocrine disrupting chemical used in a wide range of consumer products including photoactive dyes used in thermal paper. Recent studies have shown that dermal absorption of BPA can occur when handling these papers. Yet, regulatory agencies have largely dismissed thermal paper as a major source of BPA exposure. Exposure estimates provided by agencies such as the European Food Safety Authority (EFSA) are based on assumptions about how humans interact with this material, stating that 'typical' exposures for adults involve only one handling per day for short periods of time (<1 minute), with limited exposure surfaces (three fingertips). The objective of this study was to determine how individuals handle thermal paper in one common setting: a cafeteria providing short-order meals. We observed thermal paper handling in a college-aged population (n = 698 subjects) at the University of Massachusetts' dining facility. We find that in this setting, individuals handle receipts for an average of 11.5 min, that >30% of individuals hold thermal paper with more than three fingertips, and >60% allow the paper to touch their palm. Only 11% of the participants we observed were consistent with the EFSA model for time of contact and dermal surface area. Mathematical modeling based on handling times we measured and previously published transfer coefficients, concentrations of BPA in paper, and absorption factors indicate the most conservative estimated intake from handling thermal paper in this population is 51.1 ng/kg/day, similar to EFSA's estimates of 59 ng/kg/day from dermal exposures. Less conservative estimates, using published data on concentrations in thermal paper and transfer rates to skin, indicate that exposures are likely significantly higher. Based on our observational data, we propose that the current models for estimating dermal BPA exposures are not consistent with normal human behavior and should be reevaluated.