WorldWideScience

Sample records for reduced ekman pumping

  1. Role of Ekman Transport Versus Ekman Pumping in Driving Summer Upwelling in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Dakui; WANG Hui; LI Ming; LIU Guimei; WU Xiangyu

    2013-01-01

    Relative roles of Ekman transport and Ekman pumping in driving summer upwelling in the South China Sea (SCS) are examined using QuikSCAT scatterometer wind data.The major upwelling regions in the SCS are the coastal regions east and southeast of Vietnam (UESEV),east and southeast of Hainan Island (UESEH),and southeast of Guangdong province (USEG).It is shown that the Ekman transport due to alongshore winds and Ekman pumping due to offshore wind stress curl play different roles in the three upwelling systems.In UESEV,Ekman pumping and Ekman transport are equally important in generating upwelling.The Ekman transport increases linearly from 0.49 Sv in May to 1.23 Sv in August,while the Ekman pumping increases from 0.36 to 1.22 Sv during the same period.In UESEH,the mean estimates of Ekman transport and Ekman pumping are 0.14 and 0.07 Sv,respectively,indicating that 33% of the total wind-driven upwelling is due to Ekman pumping.In USEG,the mean Ekman transport is 0.041 Sv with the peak occurring in July,while Ekman pumping is much smaller (0.003 on average),indicating that the upwelling in this area is primarily driven by Ekman transport.In the summers of 2003 and 2007 following E1 Ni(n)o-Southem Oscillation (ENSO) events,both Ekman transport and Ekman pumping decrease in UESEV due to the abnormally weak southwest monsoon.During the same events,however,Ekman transport is slightly enhanced and Ekman pumping is weakened in UESEH and USEG.

  2. A nonlinear model for rotationally constrained convection with Ekman pumping

    CERN Document Server

    Julien, Keith; Calkins, Michael A; Knobloch, Edgar; Marti, Philippe; Stellmach, Stephan; Vasil, Geoffrey M

    2016-01-01

    It is a well established result of linear theory that the influence of differing mechanical boundary conditions, i.e., stress-free or no-slip, on the primary instability in rotating convection becomes asymptotically small in the limit of rapid rotation. This is accounted for by the diminishing impact of the viscous stresses exerted within Ekman boundary layers and the associated vertical momentum transport by Ekman pumping. By contrast, in the nonlinear regime recent experiments and supporting simulations are now providing evidence that the efficiency of heat transport remains strongly influenced by Ekman pumping in the rapidly rotating limit. In this paper, a reduced model is developed for the case of low Rossby number convection in a plane layer geometry with no-slip upper and lower boundaries held at fixed temperatures. A complete description of the dynamics requires the existence of three distinct regions within the fluid layer: a geostrophically balanced interior where fluid motions are predominately ali...

  3. Eddy-Induced Ekman Pumping from Sea-Surface Temperature and Surface Current Effects

    Science.gov (United States)

    Gaube, P.; Chelton, D. B.; O'Neill, L. W.

    2011-12-01

    , Ekman pumping from the wind stress curl associated with eddy-induced SST variations depends strongly on both the magnitudes of the SST anomalies and on the ambient wind direction. In some regions within the eddy interiors, the SST-induced wind stress curl acts to reduce the magnitude of the Ekman pumping from surface currents while in other regions it acts to reinforce the current induced Ekman pumping. In midlatitude regions, the Ekman pumping from eddy-induced SST variations is shown to be nearly an order of magnitude smaller than that associated with eddy-induced surface currents. Eddy-induced SST effects on Ekman pumping become more comparable to surface current effects at high latitudes, especially over the Antarctic Circumpolar Current

  4. Oscillatory superfluid Ekman pumping in Helium II and neutron stars

    CERN Document Server

    van Eysden, C Anthony

    2015-01-01

    The linear response of a superfluid, rotating uniformly in a cylindrical container and threaded with a large number of vortex lines, to an impulsive increase in the angular velocity of the container is investigated. At zero temperature and with perfect pinning of vortices to the top and bottom of the container, we demonstrate that the system oscillates persistently with a frequency proportional to the vortex line tension parameter to the quarter power. This low-frequency mode is generated by a secondary flow analogous to classical Ekman pumping that is periodically reversed by the vortex tension in the boundary layers. We compare analytic solutions to the two-fluid equations of Chandler & Baym (1986) with the spin-up experiments of Tsakadze & Tsakadze (1980) in helium II and find the frequency agrees within a factor of four, although the experiment is not perfectly suited to the application of the linear theory. We argue that this oscillatory Ekman pumping mode, and not Tkachenko modes provide a natur...

  5. A global comparision of Ekman pumping from satellite scatterometers and ocean data assimilation estimates

    Science.gov (United States)

    Lee, T.; Polito, P.; Fukumori, I.

    2002-01-01

    Ekman pumping obtained from various scaterometers are compared with those derived from ECCO model which assimilate TOPEX-derived sea level anomalies using the adjoint and Kalman filter/smoother methods.

  6. Seasonal Variability of Extratropical North Pacific Wind Stress, Ekman Pumping and Sverdrup Transport

    Science.gov (United States)

    2001-12-01

    The annual cycle of the North Pacific wind stress , Ekman pumping and Sverdrup transport is investigated by means of empirical orthogonal function... stress components. These wind stress components are averaged to 624 monthly mean fields from which monthly mean Ekman pumping and Sverdrup transport...Research (NCAR) Reanalysis daily averaged surface wind components covering the extratropical North Pacific are used to calculate daily averaged wind

  7. The effects of Ekman pumping on quasi-geostrophic Rayleigh-Benard convection

    CERN Document Server

    Plumley, Meredith; Marti, Philippe; Stellmach, Stephan

    2016-01-01

    Numerical simulations of 3D, rapidly rotating Rayleigh-Benard convection are performed using an asymptotic quasi-geostrophic model that incorporates the effects of no-slip boundaries through (i) parameterized Ekman pumping boundary conditions, and (ii) a thermal wind boundary layer that regularizes the enhanced thermal fluctuations induced by pumping. The fidelity of the model, obtained by an asymptotic reduction of the Navier-Stokes equations that implicitly enforces a pointwise geostrophic balance, is explored for the first time by comparisons of simulations against the findings of direct numerical simulations and laboratory experiments. Results from these methods have established Ekman pumping as the mechanism responsible for significantly enhancing the vertical heat transport. This asymptotic model demonstrates excellent agreement over a range of thermal forcing for Pr ~1 when compared with results from experiments and DNS at maximal values of their attainable rotation rates, as measured by the Ekman numb...

  8. The effects of latent heat release on the waves with Ekman pumping

    Science.gov (United States)

    Tang, C. M.

    1984-01-01

    The problem of the effects of the latent heat release on the waves with both upper and lower boundary frictional effects is investigated. The influence of the vertical shear of the basic wind in these models will be investigated. These investigations will shed some light on the method of solution to the problem of including the effect of Ekman pumping on the moist baroclinic waves in the model of Tang and Fichtl.

  9. Dynamics of the east India coastal current. 1. Analytic solutions forced by interior Ekman pumping and local alongshore winds

    Digital Repository Service at National Institute of Oceanography (India)

    Shankar, D.; McCreary, J.P.; Han, W.; Shetye, S.R.

    OF GEOPHYSICAL RESEARCH, VOL. 101, NO. C6, PAGES 13,975-13,991, JUNE 15, 1996 Dynamics of the East India Coastal Current 1. Analytic solutions forced by interior Ekman pumping and local alongshore winds D. Snankar Centre for Mathematical Modelling... linear, continuously stratified model is used to investigate how forcing by interior Ekman pumping and local alongshore winds affects the East India Coastal Current (EICC). Solutions are found analytically to an approximate version of the equations...

  10. Is Ekman pumping responsible for the seasonal variation of warm circumpolar deep water in the Amundsen Sea?

    Science.gov (United States)

    Kim, T. W.; Ha, H. K.; Wåhlin, A. K.; Lee, S. H.; Kim, C. S.; Lee, J. H.; Cho, Y. K.

    2017-01-01

    Ekman pumping induced by horizontally varying wind and sea ice drift is examined as an explanation for observed seasonal variation of the warm layer thickness of circumpolar deep water on the Amundsen Sea continental shelf. Spatial and temporal variation of the warm layer thickness in one of the deep troughs on the shelf (Dotson Trough) was measured during two oceanographic surveys and a two-year mooring deployment. A hydrographic transect from the deep ocean, across the shelf break, and into the trough shows a local elevation of the warm layer at the shelf break. On the shelf, the water flows south-east along the trough, gradually becoming colder and fresher due to mixing with cold water masses. A mooring placed in the trough shows a thicker and warmer layer in February and March (late summer/early autumn) and thinner and colder layer in September, October and November (late winter/early spring). The amplitude of this seasonal variation is up to 60 m. In order to investigate the effects of Ekman pumping, remotely sensed wind (Antarctic Mesoscale Prediction System wind data) and sea ice velocity and concentration (EASE Polar Pathfinder) were used. From the estimated surface stress field, the Ekman transport and Ekman pumping were calculated. At the shelf break, where the warm layer is elevated, the Ekman pumping shows a seasonal variation correlating with the mooring data. Previous studies have not been able to show a correlation between observed wind and bottom temperature, but it is shown here that when sea ice drift is taken into account the Ekman pumping at the outer shelf correlates with bottom temperature in Dotson Trough. The reason why the Ekman pumping varies seasonally at the shelf break appears to be the migration of the ice edge in the expanding polynya in combination with the wind field which on average is westward south of the shelf break.

  11. Gravitational Wave transient signal emission via Ekman Pumping in Neutron Stars during post-glitch relaxation phase

    CERN Document Server

    Singh, Avneet

    2016-01-01

    Glitches in the rotational frequency of a spinning neutron star could be promising sources of gravitational wave signals lasting between a few {\\mu}s to a few weeks. The emitted signals and their properties depend upon the internal properties of the neutron star. In stellar models that assume a super-fluid core for the neutron star, the most important physical properties are the viscosity of the super-fluid, the stratification of flow in the equilibrium state and the adiabatic sound speed. Such models were previously studied by van Eysden and Melatos (2008) and Bennett et al. (2010) following simple assumptions on all contributing factors, in which the post-glitch relaxation phase could be driven by the well-known process of 'Ekman pumping'. We explore the hydrodynamic properties of the flow of super-fluid during this phase following more relaxed assumptions on the stratification of flow and/or the pressure-density gradients within the neutron star than previously studied. We calculate the time-scales of dura...

  12. Gravitational wave transient signal emission via Ekman pumping in neutron stars during post-glitch relaxation phase

    Science.gov (United States)

    Singh, Avneet

    2017-01-01

    Glitches in the rotational frequency of a spinning neutron star could be promising sources of gravitational wave signals lasting between a few microseconds to a few weeks. The emitted signals and their properties depend upon the internal properties of the neutron star. In neutron stars, the most important physical properties of the fluid core are the viscosity of the fluid, the stratification of flow in the equilibrium state, and the adiabatic sound speed. Such models were previously studied [C. A. van Eysden and A. Melatos, Classical Quantum Gravity 25, 225020 (2008, 10.1088/0264-9381/25/22/225020); M. F. Bennett, C. A. van Eysden, and A. Melatos, Mon. Not. R. Astron. Soc. 409, 1705 (2010), 10.1111/j.1365-2966.2010.17416.x] following simple assumptions on all contributing factors, in which the post-glitch relaxation phase could be driven by the well-known process of Ekman pumping [G. Walin, J. Fluid Mech. 36, 289 (1969, 10.1017/S0022112069001662); M. Abney and R. I. Epstein, J. Fluid Mech. 312, 327 (1996), 10.1017/S0022112096002030]. We explore the hydrodynamic properties of the flow of fluid during this phase following more relaxed assumptions on the stratification of flow and the pressure-density gradients within the neutron star than previously studied. We calculate the time scales of duration as well as the amplitudes of the resulting gravitational wave signals, and we detail their dependence on the physical properties of the fluid core. We find that it is possible for the neutron star to emit gravitational wave signals in a wide range of decay time scales and within the detection sensitivity of aLIGO for selected domains of physical parameters.

  13. Seasonal variability of the Ekman transport and pumping in the upwelling system off central-northern Chile (˜ 30° S) based on a high-resolution atmospheric regional model (WRF)

    Science.gov (United States)

    Bravo, Luis; Ramos, Marcel; Astudillo, Orlando; Dewitte, Boris; Goubanova, Katerina

    2016-09-01

    Two physical mechanisms can contribute to coastal upwelling in eastern boundary current systems: offshore Ekman transport due to the predominant alongshore wind stress and Ekman pumping due to the cyclonic wind stress curl, mainly caused by the abrupt decrease in wind stress (drop-off) in a cross-shore band of 100 km. This wind drop-off is thought to be an ubiquitous feature in coastal upwelling systems and to regulate the relative contribution of both mechanisms. It has been poorly studied along the central-northern Chile region because of the lack in wind measurements along the shoreline and of the relatively low resolution of the available atmospheric reanalysis. Here, the seasonal variability in Ekman transport, Ekman pumping and their relative contribution to total upwelling along the central-northern Chile region (˜ 30° S) is evaluated from a high-resolution atmospheric model simulation. As a first step, the simulation is validated from satellite observations, which indicates a realistic representation of the spatial and temporal variability of the wind along the coast by the model. The model outputs are then used to document the fine-scale structures in the wind stress and wind curl in relation to the topographic features along the coast (headlands and embayments). Both wind stress and wind curl had a clear seasonal variability with annual and semiannual components. Alongshore wind stress maximum peak occurred in spring, second increase was in fall and minimum in winter. When a threshold of -3 × 10-5 s-1 for the across-shore gradient of alongshore wind was considered to define the region from which the winds decrease toward the coast, the wind drop-off length scale varied between 8 and 45 km. The relative contribution of the coastal divergence and Ekman pumping to the vertical transport along the coast, considering the estimated wind drop-off length, indicated meridional alternation between both mechanisms, modulated by orography and the intricate

  14. The Equatorial Ekman Layer

    CERN Document Server

    Marcotte, Florence; Soward, Andrew

    2016-01-01

    The steady incompressible viscous flow in the wide gap between spheres rotating about a common axis at slightly different rates (small Ekman number E) has a long and celebrated history. The problem is relevant to the dynamics of geophysical and planetary core flows, for which, in the case of electrically conducting fluids, the possible operation of a dynamo is of considerable interest. A comprehensive asymptotic study, in the limit E<<1, was undertaken by Stewartson (J. Fluid Mech. 1966, vol. 26, pp. 131-144). The mainstream flow, exterior to the E^{1/2} Ekman layers on the inner/outer boundaries and the shear layer on the inner sphere tangent cylinder C, is geostrophic. Stewartson identified a complicated nested layer structure on C, which comprises relatively thick quasi-geostrophic E^{2/7} (inside C) and E^{1/4} (outside C) layers. They embed a thinner E^{1/3} ageostrophic shear layer (on C), which merges with the inner sphere Ekman layer to form the E^{2/5} Equatorial Ekman layer of axial length E^{...

  15. (abstract) Ekman Pumping/Suction and Wind-Driven Ocean Circulation from ERS-1 Scatterometer Measurements Over the Arabian Sea During October 1994-October 1995

    Science.gov (United States)

    Halpern, D.; Freilich, M. H.; Weller, R. A.

    1996-01-01

    Spatial variations of the east-west and north-south components of surface wind stress are critical in studies of ocean circulation and biological-physical interactions because surface wind stress curl produces a vertical velocity in the upper ocean at the bottom of the Ekman Layer.The ERS-1 scatterometer provides reasonable coverage and direct measurements of vector of winds. Three schemes are evaluated relative to high-quality moored-bouy wind observations recorded in the central Arabian Sea, where high surface waves and high atmospheric water content during the southeast monsoon adversely affect the estimation of satellite-derived winds.

  16. On time dependent Ekman transports

    National Research Council Canada - National Science Library

    Roed, L.P

    1973-01-01

    One of the most cited papers in ocean current theories is the paper by Ekman (1905). Here we take his paper as a starting point for computing time dependent solutions for the integrated velocities or the transports.

  17. Method for Reducing Pumping Damage to Blood

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George Arthur (Inventor); Bacak, James W. (Inventor); Svejkovsky, Robert J. (Inventor); Benkowski, Robert J. (Inventor)

    1997-01-01

    Methods are provided for minimizing damage to blood in a blood pump wherein the blood pump comprises a plurality of pump components that may affect blood damage such as clearance between pump blades and housing, number of impeller blades, rounded or flat blade edges, variations in entrance angles of blades, impeller length, and the like. The process comprises selecting a plurality of pump components believed to affect blood damage such as those listed herein before. Construction variations for each of the plurality of pump components are then selected. The pump components and variations are preferably listed in a matrix for easy visual comparison of test results. Blood is circulated through a pump configuration to test each variation of each pump component. After each test, total blood damage is determined for the blood pump. Preferably each pump component variation is tested at least three times to provide statistical results and check consistency of results. The least hemolytic variation for each pump component is preferably selected as an optimized component. If no statistical difference as to blood damage is produced for a variation of a pump component, then the variation that provides preferred hydrodynamic performance is selected. To compare the variation of pump components such as impeller and stator blade geometries, the preferred embodiment of the invention uses a stereolithography technique for realizing complex shapes within a short time period.

  18. Wave energy input into the Ekman layer

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper is concerned with the wave energy input into the Ekman layer, based on 3 observational facts that surface waves could significantly affect the profile of the Ekman layer. Under the assumption of constant vertical diffusivity, the analytical form of wave energy input into the Ekman layer is derived. Analysis of the energy balance shows that the energy input to the Ekman layer through the wind stress and the interaction of the Stokes-drift with planetary vorticity can be divided into two kinds. One is the wind energy input, and the other is the wave energy input which is dependent on wind speed, wave characteristics and the wind direction relative to the wave direction. Estimates of wave energy input show that wave energy input can be up to 10% in high-latitude and high-wind speed areas and higher than 20% in the Antarctic Circumpolar Current, compared with the wind energy input into the classical Ekman layer. Results of this paper are of significance to the study of wave-induced large scale effects.

  19. Nonlinear Ekman Layer Theories and Their Applications

    Institute of Scientific and Technical Information of China (English)

    TAN Zhemin; FANG Juan; WU Rongsheng

    2006-01-01

    Based on the classical Ekman theory, a series of intermediate boundary layer models, which retain the nonlinear advective process while discard embellishments, have been proposed with the intention to understand the complex nonlinear features of the atmospheric boundary layer and its interaction with the free atmosphere. In this paper, the recent advances in the intermediate boundary-layer dynamic models are reviewed. Several intermediate models such as the boundary-layer models incorporating geostrophic momentum approximation, Ekman momentum approximation, and the weak nonlinear Ekman-layer model are a major theme.With inspection of the theoretical frameworks, the physical meaning and the limitations of each intermediate model are discussed. It is found that the qualitative descriptions of the nonlinear nature in Ekman layer made by the intermediate models are fairly consistent though the details may be different. As the application of the intermediate models is concerned, the application of the intermediate models to the study of the topographic boundary layer, frontogenesis, low-level frontal structure, and low-level jet are especially summarized in this paper. It is shown that the intermediate boundary-layer models have great potential in illustrating the low-level structures of the weather and climate systems as they are coupled with the free atmospheric models.In addition, the important remaining scientific challenges and a prospectus for future research on the intermediate model are also discussed.

  20. Ekman Spiral in Horizontally Inhomogeneous Ocean with Varying Eddy Viscosity

    Science.gov (United States)

    2015-01-01

    1 Ekman Spiral in Horizontally Inhomogeneous Ocean with Varying Eddy Viscosity...Oceanography Naval Postgraduate School, Monterey, California, USA Manuscript Click here to download Manuscript: Ekman -chu-pageoph-rev.docx 1...currently valid OMB control number. 1. REPORT DATE 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Ekman Spiral

  1. Laminar Flow in the Ocean Ekman Layer

    Science.gov (United States)

    Woods, J. T. H.

    INTRODUCTION THE EFFECT OF A STABLE DENSITY GRADIENT THE FATAL FLAW FLOW VISUALIZATION THE DISCOVERY OF LAMINAR FLOW FINE STRUCTURE WAVE-INDUCED SHEAR INSTABILITY BILLOW TURBULENCE REVERSE TRANSITION REVISED PARADIGM ONE-DIMENSIONAL MODELLING OF THE UPPER OCEAN DIURNAL VARIATION BUOYANT CONVECTION BILLOW TURBULENCE IN THE DIURNAL THERMOCLINE CONSEQUENCES FOR THE EKMAN CURRENT PROFILE SOLAR RADIATION APPLICATIONS Slippery Seas of Acapulco Pollution Afternoon Effect in Sonar Patchiness Fisheries Climate DISCUSSION CONCLUSION REFERENCES

  2. Magnetized Ekman Layer and Stewartson Layer in a Magnetized Taylor-Couette Flow

    CERN Document Server

    Liu, Wei

    2007-01-01

    In this paper we present axisymmetric nonlinear simulations about magnetized Ekman and Stewartson layers in a magnetized Taylor-Couette flow with a centrifugally stable angular-momemtum profile. The magnetic field is found to inhibit the Ekman suction. The width of the Ekman layer is reduced with increased magnetic field normal to the end plate. A uniformly-rotating region forms near the outer cylinder. A strong magnetic field leads to a steady Stewartson layer emanating from the junction between differentially rotating rings at the endcaps. The Stewartson layer becomes thinner with larger Reynolds number and penetrates deeper into the bulk flow with stronger magnetic field and larger Reynolds number. However, at Reynolds number larger than a critical value $\\sim 600$, axisymmetric, and perhaps also nonaxisymmetric, instabilities occur and result in a less prominent Stewartson layer that extends less far from the boundary.

  3. Reducing Raman noise in parametric frequency conversion by varying the input pump power

    DEFF Research Database (Denmark)

    Friis, Søren Michael Mørk; Andersen, Lasse Mejling; Rottwitt, Karsten

    2014-01-01

    The phase-matching condition of parametric frequency conversion and the impact of Raman scattering depend on the power of two separate pumps. We show that Raman noise is reduced by asymmetrically varying the pump powers.......The phase-matching condition of parametric frequency conversion and the impact of Raman scattering depend on the power of two separate pumps. We show that Raman noise is reduced by asymmetrically varying the pump powers....

  4. The role of Ekman flow and planetary waves in the oceanic cross-equatorial heat transport

    Science.gov (United States)

    Schopf, P. S.

    1980-01-01

    A numerical model is used to mechanistically simulate the oceans' seasonal cross-equatorial heat transport. The basic process of Ekman pumping and drift is able to account for a large amount of the cross-equatorial flux. Increased easterly wind stress in the winter hemisphere causes Ekman surface drift poleward, while decreased easterly stress allows a reduction in the poleward drift in the summer hemisphere. The addition of planetary and gravity waves to this model does not alter the net cross-equatorial flow, although the planetary waves are clearly seen. On comparison with Oort and Vonder Haar (1976), this adiabatic advective redistribution of heat is seen to be plausible up to 10-20 deg N, beyond which other dynamics and thermodynamics are indicated.

  5. An averaging method for nonlinear laminar Ekman layers

    DEFF Research Database (Denmark)

    Andersen, Anders Peter; Lautrup, B.; Bohr, T.

    2003-01-01

    We study steady laminar Ekman boundary layers in rotating systems using,an averaging method similar to the technique of von Karman and Pohlhausen. The method allows us to explore nonlinear corrections to the standard Ekman theory even at large Rossby numbers. We consider both the standard self...

  6. Sea surface temperature and Ekman transport in the Persian Gulf

    Directory of Open Access Journals (Sweden)

    E. H.

    2002-12-01

    Full Text Available   The wind drift motion of the water which is produced by the stress of the wind exerted upon the surface of the ocean is described by Ekmans theory (1905. Using the mean monthly values for the wind stress and SST, seasonal Ekman transport for the Persian Gulf was computed and contoured. The geostrophic winds have combined with the SST to estimate the effect of cooling due to Ekman transport of colder northern waters and inflow from the Oman Sea. The monthly SST mainly obtained from the 10 10 grided data of Levitus atlas and Hormuz Cruis Experiment for 1997.   Analyses show a NW to SE Ekman transport due to wind stress and significant interannual variability of SST on sea surface in the Persian Gulf. The seasonal variation of SST shows a continental pattern due to severe interaction between the land and sea. But these variations somehow moderates because of Ekman transport in Persian Gulf.

  7. Effects of stratification on an ocean surface Ekman layer

    Science.gov (United States)

    Pham, Hieu; Sarkar, Sutanu

    2014-11-01

    Large-eddy simulations are used to investigate the effects of stratification on structural and turbulent dynamics of an upper-ocean Ekman layer that is driven by a constant wind stress (friction velocity u*) at low latitude with Coriolis parameter f. The surface layer evolves in the presence of interior stratification whose buoyancy frequency varies among cases, taking three values: N / f = 19 , 60 and 192. At quasi-steady state, a stratified turbulent Ekman layer forms with a surface current veering to the right of the wind direction. The thickness of the Ekman layer decreases with increasing N and is found to scale with u*, f, and N, similar to the neutral atmospheric boundary layer of Zilitinkevich & Esau (2002) that is capped by a stratified layer with buoyancy frequency, N. As N increases, the speed of the Ekman current increases but the Ekman transport is invariant. The surface veering angle also increases with larger N. The shear rate and buoyancy frequency are elevated at the base of the Ekman layer. The peak of down-wind Reynolds stress occurs near the surface and scales with u*2 in all cases while the peak of cross-wind Reynolds stress occurs in the middle of the Ekman layer and decreases with increasing N.

  8. The sensitivity of rotating Rayleigh-Bénard convection to the Ekman number

    Science.gov (United States)

    Plumley, Meredith; Julien, Keith; Marti, Philippe; Stellmach, Stephan; Aurnou, Jonathan; Hawkins, Emily

    2016-11-01

    Many geophysical and astrophysical applications of rotating Rayleigh-Bénard convection require no-slip boundaries. These boundaries lead to Ekman pumping, which has a dominant impact on the heat transport and affects the transfer of energy within the system. Here I present the 2D surface of the Nusselt number as a function of the Rayleigh number (Ra) and the Ekman number (E) for no-slip boundaries, generated through a combination of results from experiments, DNS, rescaled DNS, and asymptotic simulations. The Ra - E space is mapped from the transition of the weakly-rotating into the rotation-dominated regime (E 10-7) to lower E in the rapidly-rotating regime (E 10-11). This exploration provides insight into the sensitivity of the flow to the Ekman number, specifically the effect of the boundaries on the types and ranges of flow structures and the difference between stress-free and no-slip boundaries at low E, a regime of interest for modeling planetary interiors.

  9. Reduced energy and volume air pump for a seat cushion

    Energy Technology Data Exchange (ETDEWEB)

    Vaughn, Mark R. (Albuquerque, NM); Constantineau, Edward J. (Albuquerque, NM); Groves, Gordon E. (Tijeras, NM)

    1997-01-01

    An efficient pump system for transferring air between sets of bladders in a cushion. The pump system utilizes a reversible piston within a cylinder in conjunction with an equalizing valve in the piston which opens when the piston reaches the end of travel in one direction. The weight of a seated user then forces air back across the piston from an inflated bladder to the previously deflated bladder until the pressure is equalized. In this fashion the work done by the pump is cut in half. The inflation and deflation of the different bladders is controlled to vary the pressure on the several pressure points of a seated user. A principal application is for wheel chair use to prevent pressure ulcers.

  10. Reduced energy and volume air pump for a seat cushion

    Energy Technology Data Exchange (ETDEWEB)

    Vaughn, M.R.; Constantineau, E.J.; Groves, G.E.

    1997-08-19

    An efficient pump system is described for transferring air between sets of bladders in a cushion. The pump system utilizes a reversible piston within a cylinder in conjunction with an equalizing valve in the piston which opens when the piston reaches the end of travel in one direction. The weight of a seated user then forces air back across the piston from an inflated bladder to the previously deflated bladder until the pressure is equalized. In this fashion the work done by the pump is cut in half. The inflation and deflation of the different bladders is controlled to vary the pressure on the several pressure points of a seated user. A principal application is for wheel chair use to prevent pressure ulcers. 12 figs.

  11. An investigation of Ekman upwelling in the North Atlantic

    Science.gov (United States)

    Mcclain, Charles R.; Firestone, James

    1993-01-01

    The spatial and temporal variability of the North Atlantic Ekman upwelling fields on seasonal and interannual time scales is investigated on the basis of surface winds from the Fleet Numerical Oceanography Center for 1979-1986. A pronounced minimum in the basin-wide monthly mean vertical Ekman velocities during 1981-1982 is found. It is shown that the primary source of the interannual signal was the region off NW Africa in the vicinity of the Guinea Dome. Other sectors of the basin experienced no significant interannual trends. Hydrographic data and SST data from the NW Africa sector for 1981-1986 indicate a cooling trend beginning in late 1982, consistent with increased upwelling. The fall and winter seasons' mixed layers at the center of the Guinea Dome were deeper in 1984 and 1985 than in previous years. The potential impact of large interannual variations in Ekman upwelling on basin-wide primary productivity is discussed.

  12. A numerical study of the turbulent Ekman layer

    Science.gov (United States)

    Coleman, G. N.; Ferziger, J. H.; Spalart, P. R.

    1990-01-01

    The three-dimensional time-dependent turbulent flow in a neutrally stratified Ekman layer over a smooth flat surface was numerically simulated by directly solving the Navier-Stokes equations. Issues addressed using the direct numerical simulation (DNS) fields include the presence or absence of large-scale coherent structures ('longitudinal' or 'roll' vortices) in neutrally stratified Ekman-layer turbulence, the effects of the horizontal component of the angular velocity vector (i.e., latitude), and implications for models of the PBL. Experimental and DNS profiles are compared.

  13. Eigenvalues of a baroclinic stability problem with Ekman damping

    Science.gov (United States)

    Antar, B. N.; Fowlis, W. W.

    1980-01-01

    An analytical solution is presented for the baroclinic stability problem of a Boussinesq fluid in a beta-plane channel with Ekman suction boundary conditions. All of the modes, stable and unstable, belonging to this problem are identified. It is found that an unstable mode exists for only a certain range of values of the Burger number. The value of the Burger number at the upper limit of this range increases as the Ekman number decreases. Beyond this upper limit only a damped mode exists. It is also found that this transition in parameter space from the unstable to the stable mode occurs in a discontinuous manner.

  14. PUMPS

    Science.gov (United States)

    Thornton, J.D.

    1959-03-24

    A pump is described for conveving liquids, particure it is not advisable he apparatus. The to be submerged in the liquid to be pumped, a conduit extending from the high-velocity nozzle of the injector,and means for applying a pulsating prcesure to the surface of the liquid in the conduit, whereby the surface oscillates between positions in the conduit. During the positive half- cycle of an applied pulse liquid is forced through the high velocity nozzle or jet of the injector and operates in the manner of the well known water injector and pumps liquid from the main intake to the outlet of the injector. During the negative half-cycle of the pulse liquid flows in reverse through the jet but no reverse pumping action takes place.

  15. Rotating convection-driven dynamos at low Ekman number.

    Science.gov (United States)

    Rotvig, Jon; Jones, Chris A

    2002-11-01

    We present a fully 3D self-consistent convection-driven dynamo model with reference to the geodynamo. A relatively low Ekman number regime is reached, with the aim of investigating the dynamical behavior at low viscosity. This regime is computationally very demanding, which has prompted us to adopt a plane layer model with an inclined rotation vector, and to make use of efficiently parallelized code. No hyperdiffusion is used, all diffusive operators are in the classical form. Our model has infinite Prandtl number, a Rayleigh number that scales as E(-1/3) (E being the Ekman number), and a constant Roberts number. The optimized model allows us to study dynamos with Ekman numbers in the range [10(-5),10(-4)]. In this regime we find strong-field dynamos where the induced magnetic fields satisfy Taylor's constraint to good accuracy. The solutions are characterized by (i) a MAC balance within the bulk, i.e., Coriolis, pressure, Lorentz, and buoyancy forces are of comparable magnitude, while viscous forces are only significant in thin boundary layers, (ii) the Elsasser number is O(10), (iii) the strong magnetic fields cannot prevent small-scale structures from becoming dominant over the large-scale components, (iv) the Taylor-Proudman effect is detectable, (v) the Taylorization decreases as the Ekman number is lowered, and (vi) the ageostrophic velocity component makes up 80% of the flow.

  16. New Configurations of Micro Plate-Fin Heat Sink to Reduce Coolant Pumping Power

    DEFF Research Database (Denmark)

    Kolaei, Alireza Rezania; Rosendahl, Lasse

    2012-01-01

    The thermal resistance of heat exchangers has a strong influence on the electric power produced by a thermoelectric generator (TEG). In this work, a real TEG device is applied to three configurations of micro plate-fin heat sink. The distance between certain microchannels is varied to find...... the optimum heat sink configuration. The particular focus of this study is to reduce the coolant mass flow rate by considering the thermal resistances of the heat sinks and, thereby, to reduce the coolant pumping power in the system. The threedimensional governing equations for the fluid flow and the heat...... heat sink configurations reduces the coolant pumping power in the system....

  17. Ekman Upwelling, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality Ekman current (in zonal, meridional, and modulus sets) and Ekman upwelling data. This data begins with wind velocity...

  18. Ekman Upwelling, METOP ASCAT, 0.25 degrees, Global, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time Ekman current (in zonal, meridional, and modulus sets) and Ekman upwelling data. This data begins with wind velocity...

  19. Ekman Upwelling, METOP ASCAT, 0.25 degrees, Global, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time Ekman current (in zonal, meridional, and modulus sets) and Ekman upwelling data. This data begins with wind velocity...

  20. Ekman Upwelling, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality Ekman current (in zonal, meridional, and modulus sets) and Ekman upwelling data. This data begins with wind velocity...

  1. Terbutaline pump maintenance therapy after threatened preterm labour for reducing adverse neonatal outcomes.

    Science.gov (United States)

    Chawanpaiboon, Saifon; Laopaiboon, Malinee; Lumbiganon, Pisake; Sangkomkamhang, Ussanee S; Dowswell, Therese

    2014-03-23

    After successful inhibition of threatened preterm labour women are at high risk of recurrent preterm labour. Terbutaline pump maintenance therapy has been used to reduce adverse neonatal outcomes. This review replaces an earlier Cochrane review, published in 2002, which is no longer being updated by the team. To determine the effectiveness of terbutaline pump maintenance therapy after threatened preterm labour in reducing adverse neonatal outcomes. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2014) and reference lists of retrieved studies. Randomised controlled trials comparing terbutaline pump therapy with alternative therapy, placebo, or no therapy after arrest of threatened preterm labour. Two review authors independently assessed the studies for inclusion and then extracted data as eligible for inclusion in qualitative and quantitative synthesis (meta-analysis). Four studies were included with a total of 234 women randomised. The overall methodological quality of the included studies was mixed; two studies provided very little information on study methods, there was high sample attrition in one study and in three studies the risk of performance bias was high. We found no strong evidence that terbutaline maintenance therapy offered any advantages over saline placebo or oral terbutaline maintenance therapy in reducing adverse neonatal outcomes by prolonging pregnancy among women with arrested preterm labour. The mean difference (MD) for gestational age at birth was -0.14 weeks (95% confidence interval (CI) -1.66 to 1.38) for terbutaline pump therapy compared with saline placebo pump for two trials combined. One trial reported a risk ratio (RR) of 1.17 (95% CI 0.79 to 1.73) for preterm birth (less than 37 completed weeks) and a RR of 0.97 (95% CI 0.51 to 1.84) of very preterm birth (less than 34 completed weeks) for terbutaline pump compared with saline placebo pump. We found no evidence that terbutaline pump therapy was

  2. The effects of oppositely sloping boundaries with Ekman dissipation in a nonlinear baroclinic system

    Science.gov (United States)

    Weng, H.-Y.

    1990-01-01

    The present analytical and numerical examination of the effect of the slope Delta with dissipation delta on baroclinic flows in linear and nonlinear systems uses a modified Eady channel model with oppositely sloping top and bottom Ekman layers, and truncates the spectral wave solution up to six components. Comparisons are made wherever possible with results from beta-plane dissipative systems. In the linear system, the combined effect of Delta and delta strongly stabilizes long waves. In a nonlinear system without wave-wave interaction, Delta stabilizes the flow even for small delta and reduces the domain of vacillation while enlarging the domain of single-wave steady state.

  3. Variable enstrophy flux and energy spectrum in two-dimensional turbulence with Ekman friction

    CERN Document Server

    Verma, Mahendra K

    2012-01-01

    Experiments and numerical simulations reveal that in the forward cascade regime, the energy spectrum of two-dimensional turbulence with Ekman friction deviates from Kraichnan's prediction of $k^{-3}$ power spectrum. In this letter we explain this observation using an analytic model based on variable enstrophy flux arising due to Ekman friction. We derive an expression for the enstrophy flux which exhibits a logarithmic dependence in the inertial range for the Ekman-friction dominated flows. The energy spectrum obtained using this enstrophy flux shows a power law scaling for large Reynolds number and small Ekman friction, but has an exponential behaviour for large Ekman friction and relatively small Reynolds number.

  4. Reducing Thermal Effect in End-Diode-Pumped Laser Crystal by Using a Novel Resonator

    Institute of Scientific and Technical Information of China (English)

    YAO Ai-Yun; HOU Wei; LI Hui-Qing; BI Yong; LIN Xue-Chun; GENG Ai-Cong; KONG Yu-Peng; CUI Da-Fu; XU Zu-Yan

    2005-01-01

    @@ We report a new way, i.e. double-end-pumping, to extend the stability range of a laser resonator, in advantage of making the thermal loading be effectively divided between the ends of the laser crystal to reduce the thermal effect, thus to extend the stability range.

  5. Cyclone–anticyclone vortex asymmetry mechanism and linear Ekman friction

    Energy Technology Data Exchange (ETDEWEB)

    Chefranov, S. G., E-mail: schefranov@mail.ru [Russian Academy of Sciences, Obukhov Institute of Atmospheric Physics (Russian Federation)

    2016-04-15

    Allowance for the linear Ekman friction has been found to ensure a threshold (in rotation frequency) realization of the linear dissipative–centrifugal instability and the related chiral symmetry breaking in the dynamics of Lagrangian particles, which leads to the cyclone–anticyclone vortex asymmetry. An excess of the fluid rotation rate ω{sub 0} over some threshold value determined by the fluid eigenfrequency ω (i.e., ω{sub 0} > ω) is shown to be a condition for the realization of such an instability. A new generalization of the solution of the Karman problem to determine the steady-state velocity field in a viscous incompressible fluid above a rotating solid disk of large radius, in which the linear Ekman friction was additionally taken into account, has been obtained. A correspondence of this solution and the conditions for the realization of the dissipative–centrifugal instability of a chiral-symmetric vortex state and the corresponding cyclone–anticyclone vortex asymmetry has been shown. A generalization of the well-known spiral velocity distribution in an “Ekman layer” near a solid surface has been established for the case where the fluid rotation frequency far from the disk ω differs from the disk rotation frequency ω{sub 0}.

  6. Reducing Pumping Power in Hydronic Heating and Cooling Systems with Microencapsulated Phase Change Material Slurries

    Science.gov (United States)

    Karas, Kristoffer Jason

    Phase change materials (PCMs) are being used increasingly in a variety of thermal transfer and thermal storage applications. This thesis presents the results of a laboratory study into the feasibility of improving the performance of hydronic heating and cooling systems by adding microcapsules filled with a PCM to the water used as heat transport media in these systems. Microencapsulated PCMs (MPCMs) increase the heat carrying capacity of heat transport liquids by absorbing or releasing heat at a constant temperature through a change of phase. Three sequences of tests and their results are presented: 1) Thermal cycling tests conducted to determine the melting temperatures and extent of supercooling associated with the MPCMs tested. 2) Hydronic performance tests in which MPCM slurries were pumped through a fin-and-tube, air-to-liquid heat exchanger and their thermal transfer performance compared against that of ordinary water. 3) Mechanical stability tests in which MPCM slurries were pumped in a continuous loop in order to gauge the extent of rupture due to pumping. It is shown that slurries consisting of water and MPCMs ˜ 14-24 mum in diameter improve thermal performance and offer the potential for power savings in the form of reduced pumping requirements. In addition, it is shown that while slurries of MPCMs 2-5 mum in diameter appear to exhibit better mechanical stability than slurries of larger diameter MPCMs, the smaller MPCMs appear to reduce the thermal performance of air-to-liquid heat exchangers.

  7. Intermittent Turbulence in the Very Stable Ekman Layer

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, James C.

    2001-01-05

    INTERMITTENT TURBULENCE IN THE VERY STABLE EKMAN LAYER This study describes a Direct Numerical Simulation (DNS) of a very stable Ekman layer in which a constant downward heat flux is applied at the lower boundary, thus cooling the fluid above. Numerical experiments were performed in which the strength of the imposed heat flux was varied. For downward heat fluxes above a certain critical value the turbulence becomes intermittent and, as the heat flux increases beyond this value, the flow tends to relaminarize because of the very strong ambient stratification. We adopt Mahrt?s (1999) definition of the very stable boundary layer as a boundary layer in which intermittent, rather than continuous turbulence, is observed. Numerical experiments were used to test various hypothesis of where in ?stability parameter space? the very stable boundary layer is found. These experiments support the findings of Howell and Sun (1999) that the boundary layer will exhibit intermittency and therefore be categorized as ?very stable?, when the stability parameter, z/L, exceeds unity. Another marker for the very stable boundary layer, Derbyshire?s (1990) maximum heat flux criterion, was also examined. Using a case study drawn from the simulations where turbulence intermittency was observed, the mechanism that causes the intermittence was investigated. It was found that patchy turbulence originates from a vigorous inflectional, Ekman-like instability -- a roll cell -- that lifts colder air over warmer air. The resulting convective instability causes an intense burst of turbulence. This turbulence is short-lived because the lifting motion of the roll cell, as well as the roll cell itself, is partially destroyed after the patchy turbulence is generated. Examples of intermittent turbulence obtained from the simulations appear to be consistent with observations of intermittency even though the Reynolds number of the DNS is relatively low (400).

  8. Magnetohydrodynamic Ekman layers with field-aligned flow

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, Manuel, E-mail: mnjmhd@am.uva.es [Departamento de Analisis Matematico, Universidad de Valladolid, 47005 Valladolid (Spain)

    2011-05-01

    The Ekman layer in a conducting fluid with constant angular velocity, provided with a magnetic field aligned with the flow, is studied here. The existence of solutions to the magnetohydrodynamic linearized equations depends on the balance between viscosity and resistivity, on the one hand, and the angular and Alfven velocities, on the other. In most cases, exponentially decreasing solutions exist, although their longitudinal oscillations do not need to be periodic. One of the instances without a solution is explained by the presence of Alfven waves traveling backwards along the streamlines.

  9. A PARADOX OF TRANSIENT EKMAN DRIFT MODEL AND ITS EXPLAINATION

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In view of the fact that the simple analytic model is important both in acquiring the dynamic rule of Ocean and in understanding its mechanical essence, a unified solution of transient Ekman drift model encompassing the Fredholm’s solution with constant wind and the hidaka, Nomitsu, and Defant’s solution with unsteady wind is provided, and the paradox that it is uncertain if the solution satisfies the boundary condition is pointed out and explained. The present study shows that a simply mathematical treatment is able to remove this paradox, hoping to call for the mathematicians’ notice.

  10. Reducing temperature dependence of the output energy of a quasi-continuous wave diode-pumped Nd:YAG laser.

    Science.gov (United States)

    Lee, Kangin; Kim, Youngjung; Lee, Sijin; Kwon, Jin Hyuk; Gwak, Jin Seog; Yi, Jonghoon

    2013-08-20

    It is demonstrated by numerical modeling that spectrally dispersed compound pumping diodes and low-loss pumping chamber reduced the temperature dependence of the output energy of quasi-continuous wave diode-pumped Nd:YAG lasers considerably. Several compound diodes with different spectral profiles were tested for pumping. The laser energy was calculated as a function of diode temperature from -30°C to 60°C. When a compound diode with a flat-top spectrum was used for pumping, the mean laser energy was 83% of the maximum energy of a Nd:YAG laser pumped by a diode with a narrow bandwidth. In addition, a compound diode with three emission lines was tested for pumping. When the wavelength gap between the adjacent emission lines of the pumping diode was in the range of 3-10 nm, the mean energy of the Nd:YAG laser became similar to that of a Nd:YAG laser pumped by a diode with a flat-top spectrum.

  11. Direct simulation of the stably stratified turbulent Ekman layer

    Science.gov (United States)

    Coleman, G. N.; Ferziger, J. H.; Spalart, P. R.

    1992-01-01

    The Navier-Stokes equations and the Boussinesq approximation were used to compute a 3D time-dependent turbulent flow in the stably stratified Ekman layer over a smooth surface. The simulation data are found to be in very good agreement with atmospheric measurements when nondimensionalized according to Nieuwstadt's local scaling scheme. Results suggest that, when Reynolds number effects are taken into account, the 'constant Froud number' stable layer model (Brost and Wyngaard, 1978) and the 'shearing length' stable layer model (Hunt, 1985) for the dissipitation rate of turbulent kinetic energy are both valid. It is concluded that there is good agreement between the direct numerical simulation results and large-eddy simulation results obtained by Mason and Derbyshire (1990).

  12. Intermittent Turbulence in the Very Stable Ekman Layer

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, James C [Univ. of Washington, Seattle, WA (United States)

    2001-01-01

    This study describes a Direct Numerical Simulation (DNS) of a very stable Ekman layer in which a constant downward heat flux is applied at the lower boundary, thus cooling the fluid above. Numerical experiments were performed in which the strength of the imposed heat flux was varied. For downward heat fluxes above a certain critical value the turbulence becomes intermittent and, as the heat flux increases beyond this value, the flow tends to relaminarize because of the very strong ambient stratification. We adopt Mahrt?s (1999) definition of the very stable boundary layer as a boundary layer in which intermittent, rather than continuous turbulence, is observed. Numerical experiments were used to test various hypothesis of where in ?stability parameter space? the very stable boundary layer is found. These experiments support the findings of Howell and Sun (1999) that the boundary layer will exhibit intermittency and therefore be categorized as ?very stable?, when the stability parameter, z/L, exceeds unity. Another marker for the very stable boundary layer, Derbyshire?s (1990) maximum heat flux criterion, was also examined. Using a case study drawn from the simulations where turbulence intermittency was observed, the mechanism that causes the intermittence was investigated. It was found that patchy turbulence originates from a vigorous inflectional, Ekman-like instability -- a roll cell -- that lifts colder air over warmer air. The resulting convective instability causes an intense burst of turbulence. This turbulence is short-lived because the lifting motion of the roll cell, as well as the roll cell itself, is partially destroyed after the patchy turbulence is generated. Examples of intermittent turbulence obtained from the simulations appear to be consistent with observations of intermittency even though the Reynolds number of the DNS is relatively low (400).

  13. Slow sand filters effectively reduce Phytophthora after a pathogen switch from Fusarium and a simulated pump failure.

    Science.gov (United States)

    Lee, Eric; Oki, Lorence R

    2013-09-15

    Slow sand filtration has been shown to effectively reduce Phytophthora zoospores in irrigation water. This experiment tested the reduction of Phytophthora colony forming units (CFUs) by slow sand filtration systems after switching the pathogen contaminating plant leachate from Fusarium to Phytophthora and the resilience of the system to a short period without water, as might be caused by a pump failure. The slow sand filtration system greatly reduced Phytophthora CFUs and transmission after switching the pathogens. In addition, Phytophthora reduction by the slow sand filter was equally effective before and after the simulated pump failure. Reduction of Fusarium was not seen by the SSFs, before or after the simulated pump failure. The results suggest that slow sand filters are effective at reducing larger organisms, such as Phytophthora zoospores, even after a pump failure or a change in pathogens.

  14. Inherent safety analysis of the KALIMER under a LOFA with a reduced primary pump halving time

    Energy Technology Data Exchange (ETDEWEB)

    Chang, W. P.; Kwon, Y. M.; Jeong, H. Y.; Suk, S. D.; Lee, Y. B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-02-15

    The 600 MWe, pool-type, sodium-cooled, metallic fuel loaded KALIMER-600 (Korea Advanced LiquId MEtal Reactor, 600 MWe) has been conceptually designed with an emphasis on safety by self-regulating (inherent/intrinsic) negative reactivity feedback in the core. Its inherent safety under the ATWS (Anticipated Transient Without Scram) events was demonstrated in an earlier study. Initiating events of an HCDA (Hypothetical Core Disruptive Accident), however, also need to be analyzed for assessment of the margins in the current design. In this study, a hypothetical triple-fault accident, ULOF (Unprotected Loss Of Flow) with a reduced pump halving time, is investigated as an initiator of a core disruptive accident. A ULOF with insufficient primary pump inertia may cause core sodium boiling due to a power-to-flow mismatch. If the positive sodium reactivity resulting from this boiling is not compensated for by other intrinsic negative reactivity feedbacks, the resulting core power burst would challenge the fuel integrity. The present study focuses on determination of the limit of the pump inertia for assuring inherent reactivity feedback and behavior of the core after sodium boiling as well. Transient analyses are performed with the safety analysis code SSC-K, which now incorporates a new sodium boiling model. The results show that a halving time of more than 6.0 s does not allow sodium boiling even with very conservative assumptions. Boiling takes place for a halving time of 1.8 s, and its behavior can be predicted reasonably by the SSC-K

  15. Proton pump inhibitors exert anti-allergic effects by reducing TCTP secretion.

    Directory of Open Access Journals (Sweden)

    Sunghee Choi

    Full Text Available BACKGROUND: Extracellular translationally controlled tumor protein (TCTP is known to play a role in human allergic responses. TCTP has been identified outside of macrophages, in activated mononuclear cells, and in biological fluids from allergic patients. Even TCTP devoid of signal sequences, is secreted to extracellular environment by an yet undefined mechanism. This study is aimed at understanding the mechanism of TCTP release and its regulation. A secondary goal is to see if inhibitors of TCTP release can serve as potential anti-allergic asthmatic drugs. METHODOLOGY/PRINCIPAL FINDINGS: Using Western blotting assay in HEK293 and U937 cells, we found that TCTP secretion is reduced by omeprazole and pantoprazole, both of which are proton pump inhibitors. We then transfected HEK293 cells with proton pump expression vectors to search for the effects of exogeneously overexpressed H(+/K(+-ATPase on the TCTP secretion. Based on these in vitro data we checked the in vivo effects of pantoprazole in a murine model of ovalbumin-induced allergy. Omeprazole and pantoprazole reduced TCTP secretion from HEK293 and U937 cells in a concentration-dependent fashion and the secretion of TCTP from HEK293 cells increased when they over-expressed H(+/K(+-ATPase. In a murine model of ovalbumin-induced allergy, pretreatment with pantoprazole reduced infiltration of inflammatory cells, increased goblet cells, and increased TCTP secretion induced by OVA challenge. CONCLUSION: Since Omeprazole and pantoprazole decrease the secretion of TCTP which is associated with the development of allergic reaction, they may have the potential to serve as anti-allergic (asthmatic drugs.

  16. The Ekman 60 Faces Test as a diagnostic instrument in frontotemporal dementia

    National Research Council Canada - National Science Library

    Diehl-Schmid, Janine; Pohl, Corina; Ruprecht, Carolin; Wagenpfeil, Stefan; Foerstl, Hans; Kurz, Alexander

    2007-01-01

    .... The aim of the present study was to investigate if the Ekman 60 Faces Test, an instrument to test the recognition of basic facial emotions, enables the differentiation between patients with mild FTD...

  17. Modal behavior of a reduced scale pump turbine impeller. Part II: Numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Valero, C; Huang, X; Egusquiza, E [Center for Industrial Diagnostics, Technical University of Catalonia, Av. Diagonal 647, 08028 Barcelona (Spain); Farhat, M; Avellan, F, E-mail: egusquiza@mf.upc.ed [Laboratory for Hydraulic Machines, Ecole Polytechnique Federale de Lausanne Av. De Cour 33 bis, CH-1007 Lausanne (Switzerland)

    2010-08-15

    A numerical simulation has been carried out to analyze the modal behavior of a reduced scale pump-turbine impeller. The simulation has been done using FEM method, in air and in water. The same boundary conditions than in the experiment were considered: free body in air and free body submerged in a reservoir of water. A sensitivity analysis to determine the influence of the number of elements was done. The influence of the input parameters was also taken into account. Finally, a mesh with 165000 elements for the impeller in air and of 508676 for the impeller in water was used. The results obtained with the simulation have been compared with the experimental ones (paper 1). Both the natural frequency values and the mode-shapes were compared. The numerical results showed small deviation from experiment in the first modes in modes with low modal density. In some coupled modes been found. With the updated model the mode-shapes have been analyzed. Some modes with high modal density have been found. As indicated in the experiment, the effect of the added mass reduces the natural frequencies and also changes the characteristics of the coupled modes.

  18. Numerical simulation on the "S" characteristics and pressure fluctuation of reduced pump-turbine at start-up condition

    Science.gov (United States)

    Liu, D. M.; Zheng, J. S.; Wen, G. Z.; Zhao, Y. Z.; Shi, Q. H.

    2012-11-01

    The performance of a reversible pump turbine with S-shaped characteristics is of great importance to the transition processes such as start-up and load rejection. In order to improve the "S" characteristics of reduced pump-turbine, several MGV (misaligned guide vane) schemes are calculated. The SST (shear stress turbulence) model is added to the N-S (Navier-strokes) governing equation. In order to predict the S-shaped curve accurately and develop a reliable tool for design improvement, the "S" characteristic is investigated in a whole pump-turbine including spiral casing, stay vanes, guide vanes, runner and draft tube. To validate the scheme reasonable, the mesh independent is tested. Comparison of unit discharge and unit speed performance showed that good correspondence is obtained between experimental data and calculated results. The "S shape" of reduced pump-turbine is eliminated with MGV schemes. Based on this, internal flow analysis is carried out adopting six typical MGV schemes at the same working condition. Through the calculation, we find that, first the pressure fluctuation is different between the guide vane and runner among the five MGV schemes, second the pressure fluctuation amplitude of MGV schemes D (4*35° and 16*6° average installed) is smallest, third the main frequency is the blade passing frequency and guide vane passing frequency at vane-less space and head cover, respectively. The conclusion is the "S shape" of pump-turbine can be improved with the average installed scheme.

  19. Proton Pump Inhibitor Use Is Associated With a Reduced Risk of Infection with Intestinal Protozoa.

    Science.gov (United States)

    Sheele, Johnathan M

    2017-09-11

    Proton pump inhibitors (PPIs) can kill some human protozoan parasites in cell culture better than the drug metronidazole. Clinical data showing an antiprotozoal effect for PPIs are lacking. The objective of the study is to determine if PPI use is associated with a reduced risk of having intestinal parasites. We obtained electronic medical record data for all persons who received a stool ova and parasite (O & P) examination at our tertiary care academic medical center in Cleveland, Ohio, between January 2000 and September 2014. We obtained the person's age, whether they were taking a PPI at the time of the O & P examination, and whether the pathology report indicated the presence of any parasites. χ(2) with Yates correction was used to determine if PPI use was associated with stool protozoa. Three intestinal protozoa were identified in 1199 patients taking a PPI (0.3%), and 551 intestinal parasites were identified in the 14,287 patients not taking a PPI (3.9%). There was a statistically significant lower likelihood of finding protozoa in the stool of a person taking a PPI compared with those not taking a PPI (P protozoa reported on stool O & P examination compared with those not taking a PPI. Copyright © 2017 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  20. Optimizing Blendstock Composition and Ethanol Feedstock to Reduce Gasoline Well-to-Pump CO 2 Emission

    KAUST Repository

    Zhang, Bo

    2017-06-02

    Lifecycle CO2 emission of ethanol blended gasoline was simulated to investigate how fuel properties and composition affect overall emission. Fuel research octane number (RON), octane sensitivity and ethanol content (derived from sugarcane and corn) were varied in the simulations to formulate blended fuels that economically achieve target specifications. The well-to-pump (WTP) simulation results were then analyzed to understand the effects of fuel composition on emission. Elevated ethanol content displaces aromatics and olefins required in gasoline blendstock to reach a target fuel specification. The addition of greater sugarcane-based ethanol percentage in constant aromatics and olefins fuel reduces its WTP CO2 emission. Corn-based ethanol blending does not offer CO2 emission offset due to its high production emissions. The mixing of sugarcane-based with corn-based ethanol is shown to be a potentially effective method for achieving a blended fuel with a lower lifecycle CO2 emission. Besides CO2 emission, the total greenhouse gas (GHG) emission from land-use conversions (LUC), CH4, and N2O are also significant in determining the optimal fuel blend. Herein, we present preliminary results showing that total GHG emissions significantly increase when either corn or sugarcane ethanol is blended at even small percentages; detailed results will be addressed in future communications.

  1. Reduced models and design principles for half-harmonic generation in synchronously-pumped optical parametric oscillators

    CERN Document Server

    Hamerly, Ryan; Jankowski, Marc; Fejer, Martin M; Yamamoto, Yoshihisa; Mabuchi, Hideo

    2016-01-01

    We develop reduced models that describe half-harmonic generation in a synchronously-pumped optical parametric oscillator above threshold, where nonlinearity, dispersion, and group-velocity mismatch are all relevant. These models are based on (1) an eigenmode expansion for low pump powers, (2) a simulton-like sech-pulse ansatz for intermediate powers, and (3) dispersionless box-shaped pulses for high powers. Analytic formulas for pulse compression, degenerate vs. nondegenerate operation, and stability are derived and compared to numerical and experimental results.

  2. Modal behavior of a reduced scale pump-turbine impeller. Part 1: Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Escaler, X; Huetter, J K; Egusquiza, E [Center for Industrial Diagnostics, Technical University of Catalonia, Av. Diagonal 647, Barcelona, 08028 (Spain); Farhat, M; Avellan, F, E-mail: escaler@mf.upc.ed [Laboratory for Hydraulic Machines, Ecole Polytechnique Federale de Lausanne, Av. de Cour 33 bis, Lausanne, CH-1007 (Switzerland)

    2010-08-15

    An experimental investigation has been carried out to quantify the effects of surrounding fluid on the modal behavior of a reduced scale pump-turbine impeller. The modal properties of the fluid-structure system have been obtained by Experimental Modal Analysis (EMA) with the impeller suspended in air and inside a water reservoir. The impeller has been excited with an instrumented hammer and the response has been measured by means of miniature accelerometers. The Frequency Response Functions (FRF's) have been obtained from a large number of impacting positions in order to ensure the identification of the main mode shapes. As a result, the main modes of vibration have been well characterized both in air and in water in terms of natural frequency, damping ratio and mode shape. The first mode is the 2 Nodal Diameter (ND), the second one is the 0ND and the following ones are the 3ND coupled with the 1ND. The visual observation of the animated mode shapes and the level of the Modal Assurance Criterion (MAC) have permitted to correlate the homologous modes of vibration of the fluid-structure system in air and in water. From this comparison the added mass effect on the natural frequencies and the fluid effect on the damping ratios have been quantified for the most significant modes. With the surrounding water, the natural frequencies decrease in average by 10%. On the other hand, the damping ratios increase in average by 0.5%. In any case, the damping ratio appears to decrease with the frequency value of the mode.

  3. The Influence of Horizontal Boundaries on Ekman Circulation and Angular Momentum Transport in a Cylindrical Annulus

    CERN Document Server

    Obabko, Aleksandr V; Fischer, Paul F

    2008-01-01

    We present numerical simulations of circular Couette flow in axisymmetric and fully three-dimensional geometry of a cylindrical annulus inspired by Princeton MRI liquid gallium experiment. The incompressible Navier-Stokes equations are solved with the spectral element code Nek5000 incorporating realistic horizontal boundary conditions of differentially rotating rings. We investigate the effect of changing rotation rates (Reynolds number) and of the horizontal boundary conditions on flow structure, Ekman circulation and associated transport of angular momentum through the onset of unsteadiness and three-dimensionality. A mechanism for the explanation of the dependence of the Ekman flows and circulation on horizontal boundary conditions is proposed.

  4. The influence of horizontal boundaries on Ekman circulation and angular momentum transport in a cylindrical annulus

    Energy Technology Data Exchange (ETDEWEB)

    Obabko, Aleksandr V; Cattaneo, Fausto [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); F Fischer, Paul [Division of Mathematics and Computer Science, Argonne National Laboratory, Argonne, IL 60439 (United States)], E-mail: obabko@uchicago.edu

    2008-12-15

    We present numerical simulations of circular Couette flow in axisymmetric and fully three-dimensional geometry of a cylindrical annulus inspired by Princeton magnetorotational instability (MRI) liquid gallium experiment. The incompressible Navier-Stokes equations are solved with the spectral element code Nek5000 incorporating realistic horizontal boundary conditions of differentially rotating rings. We investigate the effect of changing rotation rates (Reynolds number) and of the horizontal boundary conditions on flow structure, Ekman circulation and associated transport of angular momentum through the onset of unsteadiness and three-dimensionality. A mechanism for the explanation of the dependence of the Ekman flows and circulation on horizontal boundary conditions is proposed.

  5. Oral characteristics of a patient with Ekman-Westborg-Julin trait: a case history.

    Science.gov (United States)

    Komatsu, Tomoko; Kurihara, Tae; Ito, Yumi; Lee, Masaichi-Chang-Il; Miyagi, Atsushi; Ikeda, Masakazu

    2012-03-01

    This article presents the case of a Japanese woman who had Ekman-Westborg-Julin trait. She had general macrodontia with multituberculism, evagination of the premolar, single conical roots, shovel-shaped incisors, enamel hypoplasia, impacted tooth, dental crowding, and an open bite. The oral and general characteristics of this patient are described and include the histological and radiographic findings of the mandibular third molars. We suggest that the distinctive oral features with macrodontia of the permanent teeth, multituberculism, evagination, single conical roots, and impaction of the tooth could be defined as the Ekman-Westborg-Julin trait. © 2012 Special Care Dentistry Association and Wiley Periodicals, Inc.

  6. WASTE HEAT RECOVERY IN HEAT PUMP SYSTEMS: SOLUTION TO REDUCE GLOBAL WARMING

    Directory of Open Access Journals (Sweden)

    Y. Baradey

    2015-11-01

    Full Text Available Energy conversion technologies, where waste heat recovery systems are included, have received significant attention in recent years due to reasons that include depletion of fossil fuel, increasing oil prices, changes in climatic conditions, and global warming. For low temperature applications, there are many sources of thermal waste heat, and several recovery systems and potential useful applications have been proposed by researchers [1-4]. In addition, many types of equipment are used to recover waste thermal energy from different systems at low, medium, and high temperature applications, such as heat exchangers, waste heat recovery boiler, thermo-electric generators, and recuperators. In this paper, the focus is on waste heat recovery from air conditioners, and an efficient application of these energy resources. Integration of solar energy with heat pump technologies and major factors that affect the feasibility of heat recovery systems have been studied and reviewed as well. KEYWORDS: waste heat recovery; heat pump.

  7. Turbulent Pumping of Magnetic Flux Reduces Solar Cycle Memory and thus Impacts Predictability of the Sun's Activity

    CERN Document Server

    Karak, Bidya Binay

    2012-01-01

    Prediction of the Sun's magnetic activity is important because of its effect on space environmental conditions and climate. However, recent efforts to predict the amplitude of the solar cycle have resulted in diverging forecasts with no consensus. It is understood that the dynamical memory of the solar dynamo mechanism governs predictability and this memory is different for advection- and diffusion-dominated solar convection zones. By utilizing stochastically forced, kinematic dynamo simulations, we demonstrate that the inclusion of downward turbulent pumping of magnetic flux reduces the memory of both advection- and diffusion-dominated solar dynamos to only one cycle; stronger pumping degrades this memory further. We conclude that reliable predictions for the maximum of solar activity can be made only at the preceding minimum and for more accurate predictions, sequential data assimilation would be necessary in forecasting models to account for the Sun's short memory.

  8. The Ekman Layer and Why Tea Leaves Go to the Center of the Cup

    Science.gov (United States)

    Heavers, Richard M.; Dapp, Rachel M.

    2010-01-01

    Consider a transparent, cylindrical container filled with water and sitting in the center of a record player turntable. When the turntable is started suddenly, the container rotates with the turntable, but the bulk of the fluid initially remains at rest. A thin ([approximately]1 mm) viscous boundary layer (Ekman layer) forms almost immediately at…

  9. The Ekman Layer and Why Tea Leaves Go to the Center of the Cup

    Science.gov (United States)

    Heavers, Richard M.; Dapp, Rachel M.

    2010-01-01

    Consider a transparent, cylindrical container filled with water and sitting in the center of a record player turntable. When the turntable is started suddenly, the container rotates with the turntable, but the bulk of the fluid initially remains at rest. A thin ([approximately]1 mm) viscous boundary layer (Ekman layer) forms almost immediately at…

  10. Successful Partnering to Transform the College Library: An Interview with Richard Ekman

    Science.gov (United States)

    Hardesty, Larry; Ekman, Richard

    2004-01-01

    In recent years academic librarians have sought to partner with other organizations of higher education to establish areas of mutual interest and to work together to further these areas. Richard Ekman, as president of the Council of Independent Colleges (CIC), has involved librarians in various CIC programs. This past year, under Richard's…

  11. Anthropogenic carbon dioxide transport in the Southern Ocean driven by Ekman flow.

    Science.gov (United States)

    Ito, T; Woloszyn, M; Mazloff, M

    2010-01-07

    The Southern Ocean, with its large surface area and vigorous overturning circulation, is potentially a substantial sink of anthropogenic CO(2) (refs 1-4). Despite its importance, the mechanism and pathways of anthropogenic CO(2) uptake and transport are poorly understood. Regulation of the Southern Ocean carbon sink by the wind-driven Ekman flow, mesoscale eddies and their interaction is under debate. Here we use a high-resolution ocean circulation and carbon cycle model to address the mechanisms controlling the Southern Ocean sink of anthropogenic CO(2). The focus of our study is on the intra-annual variability in anthropogenic CO(2) over a two-year time period. We show that the pattern of carbon uptake is correlated with the oceanic vertical exchange. Zonally integrated carbon uptake peaks at the Antarctic polar front. The carbon is then advected away from the uptake regions by the circulation of the Southern Ocean, which is controlled by the interplay among Ekman flow, ocean eddies and subduction of water masses. Although lateral carbon fluxes are locally dominated by the imprint of mesoscale eddies, the Ekman transport is the primary mechanism for the zonally integrated, cross-frontal transport of anthropogenic CO(2). Intra-annual variability of the cross-frontal transport is dominated by the Ekman flow with little compensation from eddies. A budget analysis in the density coordinate highlights the importance of wind-driven transport across the polar front and subduction at the subtropical front. Our results suggest intimate connections between oceanic carbon uptake and climate variability through the temporal variability of Ekman transport.

  12. GHz-bandwidth upconversion detector using a unidirectional ring cavity to reduce multilongitudinal mode pump effects

    DEFF Research Database (Denmark)

    Meng, Lichun; Høgstedt, Lasse; Tidemand-Lichtenberg, Peter

    2017-01-01

    narrow-linewidth lasers in a fiber coupler while tuning their wavelength difference down to 10 pm or less. The SFG crystal is placed inside an Nd:YVO4 ring cavity that provides 1064 nm circulating pump powers of up to 150 W in unidirectional operation. Measured Fabry-Perot spectrum at 1064 nm confirms...... for cooling, the GHz-bandwidth upconverter can readily be extended to the mid-IR (2 - 5 mu m) as an alternative to cooled low-bandgap semiconductor detectors for applications such as high-speed free-space optical communications. (C) 2017 Optical Society of America...

  13. Potential of Demand Side Management to Reduce Carbon Dioxide Emissions Associated with the Operation of Heat Pumps

    Directory of Open Access Journals (Sweden)

    Samuel J. G. Cooper

    2013-06-01

    Full Text Available This work considers the potential reduction in the carbon dioxide emissions associated with the operation of Air Source Heat Pump which could be achieved by using demand side management. In order to achieve significant reductions in carbon dioxide emissions, it is widely envisioned that electrification of the heating sector will need to be combined with decarbonisation of the electrical supply. By influencing the times at when electric heat pumps operate such that they coincide more with electricity generation which has a low marginal carbon emissions factor, it has been suggested that these emissions could be reduced further. In order to investigate this possibility, models of the UK electrical grid based on scenarios for 2020 to 2050 have been combined with a dynamic model of an air source heat pump unit and thermal models of a population of dwellings. The performance and carbon dioxide emissions associated with the heat pumps are compared both with and without demand side management interventions intended to give preference to operation when the marginal emissions factor of the electricity being generated is low. It is found that these interventions are unlikely to be effective at achieving further reductions in emissions. A reduction of around 3% was observed in scenarios based around 2035 but in other scenarios the reduction was insignificant. In the scenarios with high wind generation (2050, the DSM scheme considered here tends to improve thermal comfort (with minimal increases in emissions rather than achieving a decrease in emissions. The reasons for this are discussed and further recommendations are made.

  14. Reducing galvanomagnetic effects in spin pumping measurement with Co{sub 75}Fe{sub 25} as a spin injector

    Energy Technology Data Exchange (ETDEWEB)

    Haidar, S. M., E-mail: haidar@imr.tohoku.ac.jp; Iguchi, R.; Yagmur, A.; Lustikova, J. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Shiomi, Y. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577 (Japan); Saitoh, E. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577 (Japan); WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); CREST, Japan Science and Technology Agency, Tokyo 102-0076 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, Tokai 319-1195 (Japan)

    2015-05-14

    We have investigated dc voltage generation induced by ferromagnetic resonance in a Co{sub 75}Fe{sub 25}/Pt film. In order to reduce rectification effects of anisotropic magnetoresistance and the planar Hall effect, which may be observed simultaneously with the inverse spin Hall effect, we selected Co{sub 75}Fe{sub 25} with extremely small anisotropic magnetoresistance as a spin injector. Using the difference in the spectral shape of voltage and in the angle dependence of in-plane magnetization among the effects, we demonstrated that the generated dc voltage is governed by the inverse spin Hall effect induced by spin pumping.

  15. The Origin of Ekman Flow in a Cavity Subject to Impulsive Rotational Motions

    Directory of Open Access Journals (Sweden)

    Wen-Jei Yang

    2001-01-01

    Full Text Available An experimental study is performed to disclose the origin of Ekman flow on the surfaces of a rotating drum resulting from fluid-structure interaction after an impulsive start of motion (referred to as the spin-up process or an impulsive stop (the spin-down process. Laser Doppler velocimetry (LDV is employed to determine instantaneous distribution of both the radial and angular velocity components in the flow field inside the rotating drum. From these results, the secondary flow and the time history of the Ekman boundary layer thickness are determined. The tracer/light sheet method is also engaged to enable real-time visualization of flow patterns. Fluid viscosity, drum size and rotational speed are varied to determine their effects on fluid-structure interactions. Results may be applied to cavity flow in rotating machinery.

  16. An analysis of the stability of the compressible Ekman boundary layer

    Science.gov (United States)

    Spall, J. R.; Wood, H. G., III

    1984-01-01

    The linear stability problem for the compressible Ekman boundary layer common to rotating fluids is formulated and the stability properties determined numerically. Three classes of unstable waves are identified (called class A, B, and C), their properties are described. The class C waves have only recently been reported in the literature and are present only in compressible Ekman boundary layers. Most of the calculations presented here are for uranium hexafluoride gas; however, critical Reynolds numbers are also computed for air and ammonia gas. Compressibility is generally found to decrease the critical Reynolds number for each class of wave. A comparison of results for the three different gases shows the stability to be largely unaffected by changes in the gas properties. Maximum growth rate calculations for each wave show the class A and B waves to be the dominant instabilities.

  17. The Ekman 60 Faces Test as a diagnostic instrument in frontotemporal dementia.

    Science.gov (United States)

    Diehl-Schmid, Janine; Pohl, Corina; Ruprecht, Carolin; Wagenpfeil, Stefan; Foerstl, Hans; Kurz, Alexander

    2007-05-01

    Frontotemporal dementia (FTD) is characterized by dramatic changes of personality and behaviour. Impaired ability of emotional processing could contribute to these symptoms, as it may lead to misinterpretation of emotional cues that would normally guide behaviour. The aim of the present study was to investigate if the Ekman 60 Faces Test, an instrument to test the recognition of basic facial emotions, enables the differentiation between patients with mild FTD and cognitively healthy subjects (HC). We found that compared to 33 cognitively healthy subjects, 25 patients with mild FTD were impaired in the recognition of basic emotions. At a cut-off score from 46 out of 60 points, the Ekman 60 Faces Test discriminated between patients with mild FTD and HC with 97% diagnostic accuracy (sensitivity: 94%; specificity: 100%). The results of the present study were consistent with the findings of prior studies on smaller patient samples.

  18. Theory and observations of Ekman flux in the chlorophyll distribution downstream of South Georgia.

    OpenAIRE

    Venables, Hugh; Meredith, Michael Paul

    2009-01-01

    A large phytoplankton bloom occurs downstream of South Georgia, an island on the northern edge of the Scotia Sea, Atlantic sector of the Southern Ocean. This is due to natural iron fertilisation being advected downstream in the Antarctic Circumpolar Current. Mapping of SeaWiFS chl-a in dynamic height/longitude space reveals the trajectory of surface water under the dual influences of geostrophic flow and Ekman flux. A theoretical estimate of the trajectory shows good agreement with observatio...

  19. USING CABLE SUSPENDED SUBMERSIBLE PUMPS TO REDUCE PRODUCTION COSTS TO INCREASE ULTIMATE RECOVERY IN THE RED MOUNTAIN FIELD IN SAN JUAN BASIN REGION

    Energy Technology Data Exchange (ETDEWEB)

    Pat Fort; Don L. Hanosh

    2003-11-01

    A joint venture between Enerdyne LLC, a small independent oil and gas producer, and Pumping Solutions Inc., developer of a low volume electric submersible pump, suspended from a cable, both based in Albuquerque, New Mexico, has re-established marginal oil production from the Red Mountain Oil Field, located in the San Juan Basin, New Mexico by working over 17 existing wells and installing submersible pumps. Resume marginal oil production operations in the Red Mountain oil fields located in McKinley County, New Mexico by installing a cable suspended electric submersible pumping system (HDESP), determine if this system can reduce lift costs making it a more cost effective production system for similar oil fields within the region, and if warranted, drill additional wells to improved the economics. Three Phases of work have been defined in the DOE Form 4600.1 Notice of Financial Assistance Award for this project, in which the project objectives are to be attained through a joint venture between Enerdyne LLC (Enerdyne), owner and operator of the fields and Pumping Solutions Inc. (PSI), developer of the submersible pumping system. Upon analysis of the results of each Phase, the DOE will determine if the results justify the continuation of the project and approve the next Phase to proceed or terminate the project and request that the wells be plugged. This topical report shall provide the DOE with Phase I results and conclusions reached by Enerdyne and PSI.

  20. Proton pump inhibitors

    Science.gov (United States)

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This ...

  1. Letter to the Editor: First direct observations of the reduced striations at pump frequencies close to the electron gyroharmonics

    Directory of Open Access Journals (Sweden)

    M. T. Rietveld

    Full Text Available It is well known that the ionospheric plasma response to high-power HF radio waves changes drastically as the heater frequency approaches harmonics of the electron gyrofrequency. These include changes in the spectrum of the stimulated electromagnetic emission, reduction in the anomalous absorption of low-power diagnostic waves propagating through the heated volume, and reduction in the large scale F-region heating. Theoretical models as well as previous experimental evidence point towards the absence of small-scale field-aligned plasma density irregularities at pump frequencies close to electron gyroharmonics as the main cause of these changes. Results presented in this paper are the first direct observations of the reduced striations at the 3rd gyroharmonic made by the CUTLASS radar. In addition, simultaneous EISCAT observations have revealed that the "enhanced ion-line" usually present in the EISCAT ion-line spectrum during the first few seconds after heater switch on, persisted at varying strengths while the heater was transmitting at frequencies close to the 3rd electron gyroharmonics.Key words. Ionosphere (active experiments; ionospheric irregularities · Radio science (ionospheric physics

  2. In situ measurements of Krypton in Xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    CERN Document Server

    Brown, Ethan; Huhmann, Christian; Weinheimer, Christian; Kettling, Hans

    2012-01-01

    A new method for measuring trace amounts of krypton in xenon using a cold trap with a residual gas analyzer has been developed, which achieves an increased sensitivity by temporarily reducing the pumping speed while expending a minimal amount of xenon. By partially closing a custom built butterfly valve between the measurement chamber and the turbomolecular pump, a sensitivity of 40 ppt has been reached. This method has been tested on an ultra-pure gas sample from Air Liquide with an unknown intrinsic krypton concentration, yielding a krypton concentration of $330 \\pm 200$ ppt.

  3. In situ measurements of krypton in xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    Science.gov (United States)

    Brown, E.; Rosendahl, S.; Huhmann, C.; Weinheimer, C.; Kettling, H.

    2013-02-01

    A new method for measuring trace amounts of krypton in xenon using a cold trap with a residual gas analyzer has been developed, which achieves an increased sensitivity by temporarily reducing the pumping speed while expending a minimal amount of xenon. By partially closing a custom built butterfly valve between the measurement chamber and the turbomolecular pump, a sensitivity of 40 ppt has been reached. This method has been tested on an ultra-pure gas sample from Air Liquide with an unknown intrinsic krypton concentration, yielding a krypton concentration of 330±200 ppt.

  4. Heparin-coated circuit during cardiopulmonary bypass. A clinical study using closed circuit, centrifugal pump and reduced heparinization.

    Science.gov (United States)

    Sellevold, O F; Berg, T M; Rein, K A; Levang, O W; Iversen, O J; Bergh, K

    1994-05-01

    A prospective randomized study was performed to investigate the effect of surface coating with covalently endpoint-attached heparin (Carmeda Bio Active Surface) and reduced general heparinization on haematological indices and complement C5 activation. Care was taken to optimize the rheological design of the system using centrifugal pump and a closed system without venting or machine suction. Twenty patients scheduled for aortocoronary bypass grafting (EF > 0.5) participated in the study. Ten patients were randomized to be treated with heparin-coated equipment (CBAS) and reduced i.v. heparin (1.5 mg.kg-1) while 10 patients treated with identical but noncoated equipment and full heparinization (3 mg.kg-1) served in a Control group. A vacuum suction was used to collect the blood from the operating field and it was autotransfused at weaning from extracorporeal circulation (ECC). Blood samples were obtained from the venous (precircuit) and arterial (postcircuit) side. We used a new and very specific method for detection of C5a based on monoclonal antibodies. The concentration of C5a was low in both groups during the operation but a significant increase was seen on days 1 and 2. In the Control group there was an increase from 10.2 ng.ml-1 +/- 1.2 to 27.5 ng.ml-1 +/- 4.8 on day 2 and in the CBAS group from 10.7 ng.ml-1 +/- 1.2 to 35.6 ng.ml-1 +/- 11.6 on day 2 (NS between groups). The granulocytes and total leukocyte count increased at the end of ECC and was maintained at the elevated level throughout the study period. The amount of free haemoglobin was high in the autotransfused blood in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. CLEAN-AIR heat pump. Reduced energy consumption for ventilation in buildings by integrating air cleaning and heat pump. Final Report; CLEAN-AIR heat pump - Reduceret energiforbrug til ventilation af bygninger ved luftrensning integreret med luft varmepumpe. Slut rapport

    Energy Technology Data Exchange (ETDEWEB)

    Fang, L.; Olesen, Bjarne W.; Molinaro, G.; Simmonsen, P.; Skocajic, S. [Danmarks Tekniske Univ. Institut for Byggeri og Anlaeg, Lyngby (Denmark); Hummelshoej, R.M.; Carlassara, L. [COWI A/S, Lyngby, (Denmark); Groenbaek, H.; Hansen, Ole R. [Exhausto A/S, Langeskov (Denmark)

    2011-07-01

    This report summarizes task 1 of the Clean Air Heat Pump project - modelling and simulation on energy savings when using the clean air heat pump for ventilation, air cleaning and energy recovery. The total energy consumption of the proposed ventilation systems using clean air heat pump technology was calculated by a theoretical model and compared with the reference ventilation systems (conventional ventilation systems). The energy compared between the two systems includes energy used for heating, cooling and fan. The simulation and energy saving calculation was made for the application of the clean air heat pump in three typical climate conditions, i.e. mild-cold, mild-hot and hot and wet climates. Real climate data recorded from three cities in 2002 was used for the calculation. The three cities were Copenhagen (Denmark), Milan (Italy) and Colombo (Sir Lanka) which represent the above three typical climate zones. For the Danish climate (the mild cold climate), the calculations show that the ventilation system using clean air heat pump technology can save up to 42% of energy cost in winter compared to the conventional ventilation system. The energy saving in summer can be as high as 66% for the ventilation system with humidity control and 9% for the ventilation system without the requirement of humidity control. Since the Danish summer climate is very mild, over 80% of the yearly energy consumption for ventilation is used during winter season. It is, therefore, estimated that more than 35% annual energy saving for ventilation is expected in Denmark using the clean air heat pump ventilation technology. For the mild hot climate, e.g. the Italian climate, the calculations show that up to 63% of the energy saving can be achieved in summer season. For the winter mode, 17% reduction of the energy cost can be expected for the domestic use. For industrial use, the energy cost of the clean air heat pump may not be favourable due to the industrial price of gas in Italy is

  6. Ekman layers in the Southern Ocean: spectral models and observations, vertical viscosity and boundary layer depth

    Directory of Open Access Journals (Sweden)

    S. Elipot

    2009-02-01

    Full Text Available Spectral characteristics of the oceanic boundary-layer response to wind stress forcing are assessed by comparing surface drifter observations from the Southern Ocean to a suite of idealized models that parameterize the vertical flux of horizontal momentum using a first-order turbulence closure scheme. The models vary in their representation of vertical viscosity and boundary conditions. Each is used to derive a theoretical transfer function for the spectral linear response of the ocean to wind stress.

    The transfer functions are evaluated using observational data. The ageostrophic component of near-surface velocity is computed by subtracting altimeter-derived geostrophic velocities from observed drifter velocities (nominally drogued to represent motions at 15-m depth. Then the transfer function is computed to link these ageostrophic velocities to observed wind stresses. The traditional Ekman model, with infinite depth and constant vertical viscosity is among the worst of the models considered in this study. The model that most successfully describes the variability in the drifter data has a shallow layer of depth O(30–50 m, in which the viscosity is constant and O(100–1000 m2 s−1, with a no-slip bottom boundary condition. The second best model has a vertical viscosity with a surface value O(200 m2 s−1, which increases linearly with depth at a rate O(0.1–1 cm s−1 and a no-slip boundary condition at the base of the boundary layer of depth O(103m. The best model shows little latitudinal or seasonal variability, and there is no obvious link to wind stress or climatological mixed-layer depth. In contrast, in the second best model, the linear coefficient and the boundary layer depth seem to covary with wind stress. The depth of the boundary layer for this model is found to be unphysically large at some latitudes and seasons, possibly a consequence of the inability of

  7. Recursive approach of EEG-segment-based principal component analysis substantially reduces cryogenic pump artifacts in simultaneous EEG-fMRI data.

    Science.gov (United States)

    Kim, Hyun-Chul; Yoo, Seung-Schik; Lee, Jong-Hwan

    2015-01-01

    Electroencephalography (EEG) data simultaneously acquired with functional magnetic resonance imaging (fMRI) data are preprocessed to remove gradient artifacts (GAs) and ballistocardiographic artifacts (BCAs). Nonetheless, these data, especially in the gamma frequency range, can be contaminated by residual artifacts produced by mechanical vibrations in the MRI system, in particular the cryogenic pump that compresses and transports the helium that chills the magnet (the helium-pump). However, few options are available for the removal of helium-pump artifacts. In this study, we propose a recursive approach of EEG-segment-based principal component analysis (rsPCA) that enables the removal of these helium-pump artifacts. Using the rsPCA method, feature vectors representing helium-pump artifacts were successfully extracted as eigenvectors, and the reconstructed signals of the feature vectors were subsequently removed. A test using simultaneous EEG-fMRI data acquired from left-hand (LH) and right-hand (RH) clenching tasks performed by volunteers found that the proposed rsPCA method substantially reduced helium-pump artifacts in the EEG data and significantly enhanced task-related gamma band activity levels (p=0.0038 and 0.0363 for LH and RH tasks, respectively) in EEG data that have had GAs and BCAs removed. The spatial patterns of the fMRI data were estimated using a hemodynamic response function (HRF) modeled from the estimated gamma band activity in a general linear model (GLM) framework. Active voxel clusters were identified in the post-/pre-central gyri of motor area, only from the rsPCA method (uncorrected p<0.001 for both LH/RH tasks). In addition, the superior temporal pole areas were consistently observed (uncorrected p<0.001 for the LH task and uncorrected p<0.05 for the RH task) in the spatial patterns of the HRF model for gamma band activity when the task paradigm and movement were also included in the GLM.

  8. Association of Proton Pump Inhibitors With Reduced Risk of Warfarin-Related Serious Upper Gastrointestinal Bleeding.

    Science.gov (United States)

    Ray, Wayne A; Chung, Cecilia P; Murray, Katherine T; Smalley, Walter E; Daugherty, James R; Dupont, William D; Stein, C Michael

    2016-12-01

    Proton pump inhibitors (PPIs) might reduce the risk of serious warfarin-related upper gastrointestinal bleeding, but the evidence of their efficacy for this indication is limited. A gastroprotective effect of PPIs would be particularly important for patients who take warfarin with antiplatelet drugs or nonselective nonsteroidal anti-inflammatory drugs (NSAIDs), which further increase the risk of gastrointestinal bleeding. This retrospective cohort study of patients beginning warfarin treatment in Tennessee Medicaid and the 5% National Medicare Sample identified 97,430 new episodes of warfarin treatment with 75,720 person-years of follow-up. The study end points were hospitalizations for upper gastrointestinal bleeding potentially preventable by PPIs and for bleeding at other sites. Patients who took warfarin without PPI co-therapy had 119 hospitalizations for upper gastrointestinal bleeding per 10,000 person-years of treatment. The risk decreased by 24% among patients who received PPI co-therapy (adjusted hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.63-0.91). There was no significant reduction in the risk of other gastrointestinal bleeding hospitalizations (HR, 1.07; 95% CI, 0.94-1.22) or non-gastrointestinal bleeding hospitalizations (HR, 0.98; 95% CI, 0.84-1.15) in this group. Among patients concurrently using antiplatelet drugs or NSAIDs, those without PPI co-therapy had 284 upper gastrointestinal bleeding hospitalizations per 10,000 person-years of warfarin treatment. The risk decreased by 45% (HR, 0.55; 95% CI, 0.39-0.77) with PPI co-therapy. PPI co-therapy had no significant protective effect for warfarin patients not using antiplatelet drugs or NSAIDs (HR, 0.86; 95% CI, 0.70-1.06). Findings were similar in both study populations. In an analysis of patients beginning warfarin treatment in Tennessee Medicaid and the 5% National Medicare Sample, PPI co-therapy was associated with reduced risk of warfarin-related upper gastrointestinal bleeding; the

  9. New Directions for Higher Education: Q&A with Richard Ekman on Challenges, Misconceptions Facing Independent Colleges

    Science.gov (United States)

    DiSalvio, Philip

    2014-01-01

    In April 2013, "NEJHE" launched its "New Directions for Higher Education series" to examine emerging issues, trends and ideas that have an impact on higher education policies, programs and practices. In this installment, DiSalvio interviews Richard Ekman, president of the Council of Independent Colleges (CIC), an association of…

  10. New Directions for Higher Education: Q&A with Richard Ekman on Challenges, Misconceptions Facing Independent Colleges

    Science.gov (United States)

    DiSalvio, Philip

    2014-01-01

    In April 2013, "NEJHE" launched its "New Directions for Higher Education series" to examine emerging issues, trends and ideas that have an impact on higher education policies, programs and practices. In this installment, DiSalvio interviews Richard Ekman, president of the Council of Independent Colleges (CIC), an association of…

  11. High biological productivity in the central Arabian Sea during the summer monsoon driven by Ekman pumping and lateral advection

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Madhupratap, M.; DileepKumar, M.; Muraleedharan, P.M.; DeSouza, S.N.; Gauns, M.; Sarma, V.V.S.S.

    ., Oecol o gia , 1988, 75 , 110 ? 113. 23. Ravishankar, K. V., Uma Shaanker, R. and Gan e shaiah, K. N., J. Biol. Sci ., 1995, 20 , 89 ? 103. 24. Charnov, E. L., in The Theory of Sex Allocation , Princeton Un i v e r s ity Press, New...

  12. Reduced dimer production in solar-simulator-pumped continuous wave iodine lasers based on model simulations and scaling and pumping studies

    Science.gov (United States)

    Costen, Robert C.; Heinbockel, John H.; Miner, Gilda A.; Meador, Willard E., Jr.; Tabibi, Bagher M.; Lee, Ja H.; Williams, Michael D.

    1995-01-01

    A numerical rate equation model for a continuous wave iodine laser with longitudinally flowing gaseous lasant is validated by approximating two experiments that compare the perfluoroalkyl iodine lasants n-C3F7I and t-C4F9I. The salient feature of the simulations is that the production rate of the dimer (C4F9)2 is reduced by one order of magnitude relative to the dimer (C3F7)2. The model is then used to investigate the kinetic effects of this reduced dimer production, especially how it improves output power. Related parametric and scaling studies are also presented. When dimer production is reduced, more monomer radicals (t-C4F9) are available to combine with iodine ions, thus enhancing depletion of the laser lower level and reducing buildup of the principal quencher, molecular iodine. Fewer iodine molecules result in fewer downward transitions from quenching and more transitions from stimulated emission of lasing photons. Enhanced depletion of the lower level reduces the absorption of lasing photons. The combined result is more lasing photons and proportionally increased output power.

  13. BIOMATERIALS FOR ROTARY BLOOD PUMPS

    NARCIS (Netherlands)

    VANOEVEREN, W

    1995-01-01

    Rotary blood pumps are used for cardiac assist and cardiopulmonary support since mechanical blood damage is less than with conventional roller pumps. The high shear rate in the rotary pump and the reduced anticoagulation of the patient during prolonged pumping enforces high demands on the biocompati

  14. Operative strategies to reduce cerebral embolic events during on- and off-pump coronary artery bypass surgery: A stratified, prospective randomized trial.

    Science.gov (United States)

    Halkos, Michael E; Anderson, Aaron; Binongo, Jose Nilo G; Stringer, Anthony; Lasanajak, Yi; Thourani, Vinod H; Lattouf, Omar M; Guyton, Robert A; Baio, Kim T; Sarin, Eric; Keeling, William B; Cook, N Renee; Carssow, Katherine; Neill, Alexis; Glas, Kathryn E; Puskas, John D

    2017-10-01

    To determine the impact of different aortic clamping strategies on the incidence of cerebral embolic events during coronary artery bypass grafting (CABG). Between 2012 and 2015, 142 patients with low-grade aortic disease (epiaortic ultrasound grade I/II) undergoing primary isolated CABG were studied. Those undergoing off-pump CABG were randomized to a partial clamp (n = 36) or clampless facilitating device (CFD; n = 36) strategy. Those undergoing on-pump CABG were randomized to a single-clamp (n = 34) or double-clamp (n = 36) strategy. Transcranial Doppler ultrasonography (TCD) was performed to identify high-intensity transient signals (HITS) in the middle cerebral arteries during periods of aortic manipulation. Neurocognitive testing was performed at baseline and 30-days postoperatively. The primary endpoint was total number of HITS detected by TCD. Groups were compared using the Mann-Whitney U test. In the off-pump group, the median number of total HITS were higher in the CFD subgroup (30.0; interquartile range [IQR], 22-43) compared with the partial clamp subgroup (7.0; IQR, 0-16; P 1 CFD (12.5 [IQR, 4-19] vs 36.0 [IQR, 25-47]; P = .001). In the on-pump group, the median number of total HITS was 10.0 (IQR, 3-17) in the single-clamp group, compared with 16.0 (IQR, 4-49) in the double-clamp group (P = .10). There were no differences in neurocognitive outcomes across the groups. For patients with low-grade aortic disease, the use of CFDs was associated with an increased rate of cerebral embolic events compared with partial clamping during off-pump CABG. A single-clamp strategy during on-pump CABG did not significantly reduce embolic events compared with a double-clamp strategy. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  15. Reduced anesthetic requirements, diminished brain plasma membrane Ca(2+)-ATPase pumping, and enhanced brain synaptic plasma membrane phospholipid methylation in diabetic rats: effects of insulin.

    Science.gov (United States)

    Janicki, P K; Horn, J L; Singh, G; Janson, V E; Franks, W T; Franks, J J

    1995-01-01

    We have recently reported that streptozocin (STZ)-induced diabetes in rats was associated with i) reduced Ca2+ pumping by rat brain synaptic plasma membrane Ca(2+)-ATPase (PMCA) and ii) a substantial reduction in the partial pressures of halothane and xenon required to prevent movement in response to stimulation (minimum effective dose or MED). MED for both agents correlated well with the degree of hemoglobin glycation and with PMCA activity. We now report that MEDs for isoflurane, enflurane, and desflurane were also substantially reduced in STZ-diabetic rats, compared with placebo-injected controls. In addition, we examined the effect of insulin treatment, begun 2 weeks after induction of diabetes and continued for 3 more weeks, on isoflurane MED and on brain synaptic PMCA and phospholipid-N-methyltransferase I (PLMT I), another enzyme altered by inhalation anesthetics (IA). Partial treatment of diabetes, as indicated by decreased glycated hemoglobin (GHb) compared to untreated diabetic rats, was associated with an isoflurane MED of 1.05 vol%, intermediate between a control mean of 1.57 vol% and an untreated diabetic mean of 0.82 vol% (p SPM from diabetic rats did not differ from control values, but PMCA pumping in SPM from the D-M was reduced to about 85% of control levels. Good correlation (r = 0.89, p < 0.01) was found between isoflurane MED and GHb in all treatment groups. These findings provide further evidence for an important role for PMCA in IA action. They also suggest that anesthetic effects on the calcium pump at specific anatomic sites may be of major importance in producing anesthesia.

  16. Consecutive salinomycin treatment reduces doxorubicin resistance of breast tumor cells by diminishing drug efflux pump expression and activity.

    Science.gov (United States)

    Hermawan, Adam; Wagner, Ernst; Roidl, Andreas

    2016-03-01

    Chemoresistance is a major challenge for the successful therapy of breast cancer. The discovery of salinomycin as an anticancer stem cell drug provides progress in overcoming chemoresistance. However, it remains to be elucidated whether salinomycin treatment is able to sensitize cancer cells to chemotherapeutic drugs. In the present study, we consecutively treated epithelial MCF-7 and BT-474 breast cancer cells as well as mesenchymal MDA-MB 231 and MDA-MB 436 cells with salinomycin, and analyzed the gene expression of the two prominent multiple drug resistance (MDR) genes, MDR1 and BCRP1. We found that repeated treatment with salinomycin generated resistance against this drug in all cell lines and increased the chemosensitivity towards doxorubicin. Drug efflux pump gene expression and pump activity of MDR1 and BCRP1 were downregulated in almost all cell lines, except for MDR1 in the MDA-MB 231 cells. Consequently, the intracellular doxorubicin accumulation was increased compared to the respective parental cells. Our findings suggest a novel treatment option for MDR tumors by sensitizing these tumors via salinomycin pretreatment.

  17. In situ measurements of krypton in xenon gas with a quadrupole mass spectrometer following a cold-trap at a temporarily reduced pumping speed

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Ethan; Rosendahl, Stephan; Huhmann, Christian; Kettling, Hans; Schlak, Martin; Weinheimer, Christian [Muenster Univ. (Germany). Inst. fuer Kernphysik

    2013-07-01

    Liquid xenon detectors have risen to be extremely competitive for dark matter and neutrinoless double-beta decay searches. In order to achieve the required sensitivity, backgrounds must be reduced substantially. One important background is the beta-decay of {sup 85}Kr, which constitutes a uniform internal background in liquid xenon detectors. Cryogenic distillation can be used to reduce the krypton concentration to acceptable levels, but gas diagnostics become incredibly difficult at these ultra-pure levels. A new method for measuring the concentration of krypton in xenon has been developed, expanding on the existing technique of a cold trap and a Residual Gas Analyzer (RGA). By using a liquid nitrogen cold trap, one can take advantage of the difference in vapor pressures of krypton in xenon to freeze most of the xenon gas while allowing the krypton to pass to the measurement chamber. Here, only a few milliliters of xenon is expended in the measurement, while achieving a sensitivity of sub ppb (parts per billion). The key change is the use of a butterfly valve to partially close the opening in front of the turbomolecular pump, thereby reducing the effective pumping speed and enhancing the RGA signal.

  18. 非经典Ekman方程的解和演化条件%The Developing Conditions and Solutions of Non-classical Ekman's Equation

    Institute of Scientific and Technical Information of China (English)

    林振山

    2003-01-01

    An approximate equation of non-classical Ekman's flow and stochastic equations about Ekman's flow are set up in this paper.The developing conditions,solutions and the frequency response of the non-classical Ekman's flow are studied.The results show that the non-classicalEkman's flow will develop when the classical Ekman's flow shear is large enough and the non-classical Ekman's flow will tend to the most probable state (Us,Vs) or to (-fVe,fUe),respectively,in a similar condition or in a general condition.%建立了一个Ekman边界层的随机方程和非经典Ekman方程,研究了非经典Ekman流的频率响应、解和演化条件.有关研究结果表明,当经典Ekman流的切变足够大时,非经典Ekman流将发展起来,而且在相似条件和普适条件下,非经典Ekman流将分别朝最可几态(Us,Vs)或(-fVe,fU2)演化.

  19. Structuring of turbulence and its impact on basic features of Ekman boundary layers

    Directory of Open Access Journals (Sweden)

    I. Esau

    2013-08-01

    Full Text Available The turbulent Ekman boundary layer (EBL has been studied in a large number of theoretical, laboratory and modeling works since F. Nansen's observations during the Norwegian Polar Expedition 1893–1896. Nevertheless, the proposed analytical models, analysis of the EBL instabilities, and turbulence-resolving numerical simulations are not fully consistent. In particular, the role of turbulence self-organization into longitudinal roll vortices in the EBL and its dependence on the meridional component of the Coriolis force remain unclear. A new set of large-eddy simulations (LES are presented in this study. LES were performed for eight different latitudes (from 1° N to 90° N in the domain spanning 144 km in the meridional direction. Geostrophic winds from the west and from the east were used to drive the development of EBL turbulence. The emergence and growth of longitudinal rolls in the EBL was simulated. The simulated rolls are in good agreement with EBL stability analysis given in Dubos et al. (2008. The destruction of rolls in the westerly flow at low latitude was observed in simulations, which agrees well with the action of secondary instability on the rolls in the EBL. This study quantifies the effect of the meridional component of the Coriolis force and the effect of rolls in the EBL on the internal EBL parameters such as friction velocity, cross-isobaric angle, parameters of the EBL depth and resistance laws. A large impact of the roll development or destruction is found. The depth of the EBL in the westerly flow is about five times less than it is in the easterly flow at low latitudes. The EBL parameters, which depend on the depth, also exhibit large difference in these two types of the EBL. Thus, this study supports the need to include the horizontal component of the Coriolis force into theoretical constructions and parameterizations of the boundary layer in models.

  20. Reduced aeration affects the expression of the NorB efflux pump of Staphylococcus aureus by posttranslational modification of MgrA.

    Science.gov (United States)

    Truong-Bolduc, Que Chi; Hsing, Liao Chun; Villet, Regis; Bolduc, Gilles R; Estabrooks, Zoe; Taguezem, G Florent; Hooper, David C

    2012-04-01

    We previously showed that at acid pH, the transcription of norB, encoding the NorB efflux pump, increases due to a reduction in the phosphorylation level of MgrA, which in turn leads to a reduction in bacterial killing by moxifloxacin, a substrate of the NorB efflux pump. In this study, we demonstrated that reduced oxygen levels did not affect the transcript levels of mgrA but modified the dimerization of the MgrA protein, which remained mostly in its monomeric form. Under reduced aeration, we also observed a 21.7-fold increase in the norB transcript levels after 60 min of growth that contributed to a 4-fold increase in the MICs of moxifloxacin and sparfloxacin for Staphylococcus aureus RN6390. The relative proportions of MgrA in monomeric and dimeric forms were altered by treatment with H(2)O(2), but incubation of purified MgrA with extracts of cells grown under reduced but not normal aeration prevented MgrA from being converted to its dimeric DNA-binding form. This modification was associated with cleavage of a fragment of the dimerization domain of MgrA without change in MgrA phosphorylation and an increase in transcript levels of genes encoding serine proteases in cells incubated at reduced aeration. Taken together, these data suggest that modification of MgrA by proteases underlies the reversal of its repression of norB and increased resistance to NorB substrates in response to reduced-aeration conditions, illustrating a third mechanism of posttranslational modification, in addition to oxidation and phosphorylation, that modulates the regulatory activities of MgrA.

  1. USING CABLE SUSPENDED SUBMERSIBLE PUMPS TO REDUCE PRODUCTION COSTS TO INCREASE ULTIMATE RECOVERY IN THE RED MOUNTAIN FIELD OF THE SAN JUAN BASIN REGION

    Energy Technology Data Exchange (ETDEWEB)

    Don L. Hanosh

    2004-11-01

    This report discusses: (1) being able to resume marginal oil production operations in the Red Mountain Oil Field, located in McKinley County, New Mexico by installing a cable suspended electric submersible pumping system (HDESP); (2) determining if this system can reduce life costs making it a more cost effective production system for similar oil fields within the region, and if warranted, drill additional wells to improve the economics. In April 2003, a cooperative 50% cost share agreement between Enerdyne and the DOE was executed to investigate the feasibility of using cable suspended electric submersible pumps to reduce the life costs and increase the ultimate oil recovery of the Red Mountain Oil Field, located on the Chaco Slope of the San Juan Basin, New Mexico. The field was discovered in 1934 and has produced approximately 55,650 cubic meters (m{sup 3}), (350,000 barrels, 42 gallons) of oil. Prior to April 2003, the field was producing only a few cubic meters of oil each month; however, the reservoir characteristics suggest that the field retains ample oil to be economic. This field is unique, in that, the oil accumulations, above fresh water, occur at depths from 88-305 meters, (290 feet to 1000 feet), and serves as a relatively good test area for this experiment.

  2. Centrifugal pumps

    CERN Document Server

    Anderson, HH

    1981-01-01

    Centrifugal Pumps describes the whole range of the centrifugal pump (mixed flow and axial flow pumps are dealt with more briefly), with emphasis on the development of the boiler feed pump. Organized into 46 chapters, this book discusses the general hydrodynamic principles, performance, dimensions, type number, flow, and efficiency of centrifugal pumps. This text also explains the pumps performance; entry conditions and cavitation; speed and dimensions for a given duty; and losses. Some chapters further describe centrifugal pump mechanical design, installation, monitoring, and maintenance. The

  3. Pumping life

    DEFF Research Database (Denmark)

    Sitsel, Oleg; Dach, Ingrid; Hoffmann, Robert Daniel

    2012-01-01

    of membrane proteins: P-type ATPase pumps. This article takes the reader on a tour from Aarhus to Copenhagen, from bacteria to plants and humans, and from ions over protein structures to diseases caused by malfunctioning pump proteins. The magazine Nature once titled work published from PUMPKIN ‘Pumping ions......’. Here we illustrate that the pumping of ions means nothing less than the pumping of life....

  4. Theoretical Prediction of the Pumping Performance of Dry Pumps (Taking the Scroll Pump and the Screw Pump by Way of Example)

    Science.gov (United States)

    Sawada, Tadashi; Ohbayashi, Tetsuro

    Since almost all commercially provided dry pumps are of the positive displacement type, the leak flow through clearance between displacement chambers in the pump is a dominant factor which determines pumping performance. Prediction methods for the pumping performance of dry pumps are explained by comparing it to the scroll pump and the screw pump. The scroll pump has long clearances, but the screw pump has relatively short ones, and the volume of the chambers reduces from the inlet toward the outlet in the scroll pump, but that in the screw pump is kept constant throughout the pumping process. Such a structural difference produces a small difference in the way of treating leak flow. These two methods can be applied to the other dry pumps requiring only minor modification.

  5. Reduced volume and increased training intensity elevate muscle Na+/K+ pump {alpha}2-subunit expression as well as short- and long-term work capacity in humans

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Gunnarsson, Thomas Petursson; Wendell, Jesper;

    2009-01-01

    The present study examined muscle adaptations and alterations in work capacity in endurance-trained runners as a result of a reduced amount of training combined with speed endurance training. Seventeen runners were for a 6- to 9-wk period assigned to either a speed endurance group with a 25......% reduction in the amount of training but including speed endurance training consisting of 6-12 30-s sprint runs 3-4 times a week (SET, n=12) or a control group (CON, n=5), which continued the endurance training (about 55 km(.)wk(-1)). For SET the expression of the muscle Na(+)/K(+) pump alpha2-subunit was 68......% higher (Ptraining period. In SET, VO2-max...

  6. Magnetocaloric pump

    Science.gov (United States)

    Brown, G. V.

    1973-01-01

    Very cold liquids and gases such as helium, neon, and nitrogen can be pumped by using magnetocaloric effect. Adiabatic magnetization and demagnetization are used to alternately heat and cool slug of pumped fluid contained in closed chamber.

  7. Emotion recognition from facial expressions: a normative study of the Ekman 60-Faces Test in the Italian population.

    Science.gov (United States)

    Dodich, Alessandra; Cerami, Chiara; Canessa, Nicola; Crespi, Chiara; Marcone, Alessandra; Arpone, Marta; Realmuto, Sabrina; Cappa, Stefano F

    2014-07-01

    The Ekman 60-Faces (EK-60F) Test is a well-known neuropsychological tool assessing emotion recognition from facial expressions. It is the most employed task for research purposes in psychiatric and neurological disorders, including neurodegenerative diseases, such as the behavioral variant of Frontotemporal Dementia (bvFTD). Despite its remarkable usefulness in the social cognition research field, to date, there are still no normative data for the Italian population, thus limiting its application in a clinical context. In this study, we report procedures and normative data for the Italian version of the test. A hundred and thirty-two healthy Italian participants aged between 20 and 79 years with at least 5 years of education were recruited on a voluntary basis. They were administered the EK-60F Test from the Ekman and Friesen series of Pictures of Facial Affect after a preliminary semantic recognition test of the six basic emotions (i.e., anger, fear, sadness, happiness, disgust, surprise). Data were analyzed according to the Capitani procedure [1]. The regression analysis revealed significant effects of demographic variables, with younger, more educated, female subjects showing higher scores. Normative data were then applied to a sample of 15 bvFTD patients which showed global impaired performance in the task, consistently with the clinical condition. We provided EK-60F Test normative data for the Italian population allowing the investigation of global emotion recognition ability as well as selective impairment of basic emotions recognition, both for clinical and research purposes.

  8. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  9. Meat batter production in an extended vane pump-grinder injecting curing salt solutions to reduce energy requirements: variation of curing salt amount injected with the solution.

    Science.gov (United States)

    Irmscher, Stefan B; Terjung, Eva-Maria; Gibis, Monika; Herrmann, Kurt; Kohlus, Reinhard; Weiss, Jochen

    2017-01-01

    The integration of a nozzle in an extended vane pump-grinder system may enable the continuous injection of curing salt solutions during meat batter production. The purpose of this work was to examine the influence of the curing salt amount injected with the solution (0-100%) on protein solubilisation, water-binding, structure, colour and texture of emulsion-type sausages. The amount of myofibrillar protein solubilised during homogenisation varied slightly from 33 to 36 g kg(-1) . Reddening was not noticeably impacted by the later addition of nitrite. L(*) ranged from 66.9 ± 0.3 to 67.8 ± 0.3, a(*) from 10.9 ± 0.1 to 11.2 ± 0.1 and b(*) from 7.7 ± 0.1 to 8.0 ± 0.1. Although softer sausages were produced when only water was injected, firmness increased with increasing curing salt amount injected and was similar to the control when the full amount of salt was used. The substitution of two-thirds of ice with a liquid brine may enable energy savings due to reduced power consumptions of the extended vane pump-grinder system by up to 23%. The injection of curing salt solutions is feasible without affecting structure and colour negatively. This constitutes a first step towards of an 'ice-free' meat batter production allowing for substantial energy savings due to lower comminution work. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Heat pumps

    CERN Document Server

    Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

    2013-01-01

    Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

  11. USING CABLE SUSPENDED SUBMERSIBLE PUMPS TO REDUCE PRODUCTION COSTS TO INCREASE ULTIMATE RECOVERY IN THE RED MOUNTAIN FIELD IN SAM JUAN BASIN REGION

    Energy Technology Data Exchange (ETDEWEB)

    Don L. Hanosh

    2004-08-01

    A joint venture between Enerdyne LLC, a small independent oil and gas producer, and Pumping Solutions Inc., developer of a low volume electric submersible pump, suspended from a cable, both based in Albuquerque, New Mexico, has re-established marginal oil production from the Red Mountain Oil Field, located in the San Juan Basin, New Mexico by working over 17 existing wells and installing submersible pumps.

  12. Reduced anesthetic requirements in aged rats: association with altered brain synaptic plasma membrane Ca(2+)-ATPase pump and phospholipid methyltransferase I activities.

    Science.gov (United States)

    Horn, J L; Janicki, P K; Singh, G; Wamil, A W; Franks, J J

    1996-01-01

    Aging is associated with a decrease in anesthetic requirements. Animal models of aging manifest alteration of brain Ca2+ homeostasis and increased methyltransferase I (PLMTI) activity. In this study we evaluated concurrently anesthetic requirements and brain plasma membrane Ca(2+)-ATPase (PMCA) and PLMTI activities in young and aged rats. Halothane, desflurane, isoflurane and xenon MEDs (lowest partial pressures that suppress a pain response) were measured in 2 and 25 month old, male Fisher-344 rats. Halothane MED was also measured in 2 and 30 month old F344/BNF1 rats, a strain that undergoes aging with less debilitation. PMCA pumping and PLMTI activities were measured in synaptic plasma membranes (SPM) prepared from the cortex and diencephalon-mesencephalon (DM). For aged Fisher-344 rats, MEDs for halothane, desflurane, isoflurane and xenon were reduced to 81%, 82%, 67% and 86%, respectively, of young controls; PMCA activity was diminished to 91% in cortical SPM and 82% in DM SPM; and cortical and DM PLMTI activities were increased to 131% and 114% of young control. For F344/BNF1 rats, MED for halothane was reduced to 87%, PMCA activity was diminished to 90% in cortical SPM and 72% DM SPM, and PLMTI activity was increased to 133% in cortical SPM and 112% in DM SPM. The strong association between age and reduced anesthetic requirements for inhalational agents on the one hand and altered PMCA and PLMTI activity on the other lends support to the underlying hypothesis that PMCA and PLMTI may be involved in the production of the anesthetic state.

  13. Centrifugal pumps

    CERN Document Server

    Gülich, Johann Friedrich

    2014-01-01

    This book gives an unparalleled, up-to-date, in-depth treatment of all kinds of flow phenomena encountered in centrifugal pumps including the complex interactions of fluid flow with vibrations and wear of materials. The scope includes all aspects of hydraulic design, 3D-flow phenomena and partload operation, cavitation, numerical flow calculations, hydraulic forces, pressure pulsations, noise, pump vibrations (notably bearing housing vibration diagnostics and remedies), pipe vibrations, pump characteristics and pump operation, design of intake structures, the effects of highly viscous flows, pumping of gas-liquid mixtures, hydraulic transport of solids, fatigue damage to impellers or diffusers, material selection under the aspects of fatigue, corrosion, erosion-corrosion or hydro-abrasive wear, pump selection, and hydraulic quality criteria. As a novelty, the 3rd ed. brings a fully analytical design method for radial impellers, which eliminates the arbitrary choices inherent to former design procedures. The d...

  14. Studies on reducing the thermal loads of solar-pumped solid state lasers; Taiyoko reiki laser no netsufuka teigen ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, K.; Yugami, H.; Naito, H.; Arashi, H. [Tohoku University, Sendai (Japan)

    1997-11-25

    It was intended to reduce the thermal loads of solar-pumped solid state lasers (highly densified solar light is irradiated directly onto a laser medium to cause excitation. No electric power is required for the excitation.). For this purpose, experiments were performed by using a selective permeation film. Solar light includes wavelengths not effective for excitation, which causes heat generation and thermal loads such as lens heating effect and thermal stress compounded refraction, degrading the laser beam quality. The Nd:YAG was used as a laser medium, and a multi-layered film (composed of SiO2 and TiO2) which cuts wavelength below 500 nm as a selective permeation film to cut light having wavelengths not required for excitation. A laser transmitting experiment revealed that the slope efficiency is improved by 27% as compared to not using the film. Beam fluctuation was improved to 45%. Using the selective permeation film has realized more efficient conversion of the solar light into a beam with better quality. The results for calculation of heat lens effect by using temperature distribution simulation showed good agreement with experimental values. Using the selective permeation film can suppress the maximum temperature of a laser rod to 68%, as well as the thermal stress. 9 figs., 2 tabs.

  15. Multiple macrodonts with odontoma in a mother and son--a variant of Ekman-Westborg-Julin syndrome. Report of a case.

    Science.gov (United States)

    Yoda, T; Ishii, Y; Honma, Y; Sakai, E; Enomoto, S

    1998-03-01

    A case of multiple macrodonts with a complex odontoma in a mother and son is reported. This condition is thought to represent a variant of the Ekman-Westborg-Julin syndrome. The authors discuss the relationship between macrodontia and odontoma, and the involvement of hereditary factors is suggested.

  16. On the seasonal cycles and variability of Florida Straits, Ekman and Sverdrup transports at 26° N in the Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    C. P. Atkinson

    2010-10-01

    Full Text Available Since April 2004 the RAPID array has made continuous measurements of the Atlantic Meridional Overturning Circulation (AMOC at 26° N. Two key components of this system are Ekman transport zonally integrated across 26° N and western boundary current transport in the Florida Straits. Whilst measurements of the AMOC as a whole are somewhat in their infancy, this study investigates what useful information can be extracted on the variability of the Ekman and Florida Straits transports using the decadal timeseries already available. Analysis is also presented for Sverdrup transports zonally integrated across 26° N.

    The seasonal cycles of Florida Straits, Ekman and Sverdrup transports are quantified at 26° N using harmonic analysis of annual and semi-annual constituents. Whilst Sverdrup transport shows clear semi-annual periodicity, calculations of seasonal Florida Straits and Ekman transports show substantial interannual variability due to contamination by variability at non-seasonal frequencies; the mean seasonal cycle for these transports only emerges from decadal length observations. The Florida Straits and Ekman mean seasonal cycles project on the AMOC with a combined peak-to-peak seasonal range of 3.5 Sv. The combined seasonal range for heat transport is 0.40 PW.

    The Florida Straits seasonal cycle possesses a smooth annual periodicity in contrast with previous studies suggesting a more asymmetric structure. No clear evidence is found to support significant changes in the Florida Straits seasonal cycle at sub-decadal periods. Whilst evidence of wind driven Florida Straits transport variability is seen at sub-seasonal and annual periods, a model run from the 1/4° eddy-permitting ocean model NEMO is used to identify an important contribution from internal oceanic variability at sub-annual and interannual periods. The Ekman transport seasonal cycle possesses less symmetric structure, due in part to different seasonal transport

  17. Ferroelectric Pump

    Science.gov (United States)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    2000-01-01

    A ferroelectric pump has one or more variable volume pumping chambers internal to a housing. Each chamber has at least one wall comprising a dome shaped internally prestressed ferroelectric actuator having a curvature and a dome height that varies with an electric voltage applied between an inside and outside surface of the actuator. A pumped medium flows into and out of each pumping chamber in response to displacement of the ferroelectric actuator. The ferroelectric actuator is mounted within each wall and isolates each ferroelectric actuator from the pumped medium, supplies a path for voltage to be applied to each ferroelectric actuator, and provides for positive containment of each ferroelectric actuator while allowing displacement of the entirety of each ferroelectric actuator in response to the applied voltage.

  18. Jarvik 2000 pump technology and miniaturization.

    Science.gov (United States)

    Jarvik, Robert

    2014-01-01

    Blood-pump miniaturization has made amazing progress, reducing the pump diameter to one-tenth of the size of previous positive displacement pumps. In particular, axial-flow-pump technology allows tiny pumps running at high speeds to deliver from 2 to 10 L/min. A review of the background inventions of the Jarvik 2000 technology is presented, together with the reason that making pumps smaller than demanded by the particular application for which they are designed is counterproductive. Pump miniaturization is nearing its practical limit. The optimization of performance and patient outcomes should remain our primary design goal.

  19. Underground pumped hydroelectric storage

    Science.gov (United States)

    Allen, R. D.; Doherty, T. J.; Kannberg, L. D.

    1984-07-01

    Underground pumped hydroelectric energy storage was conceived as a modification of surface pumped storage to eliminate dependence upon fortuitous topography, provide higher hydraulic heads, and reduce environmental concerns. A UPHS plant offers substantial savings in investment cost over coal-fired cycling plants and savings in system production costs over gas turbines. Potential location near load centers lowers transmission costs and line losses. Environmental impact is less than that for a coal-fired cycling plant. The inherent benefits include those of all pumped storage (i.e., rapid load response, emergency capacity, improvement in efficiency as pumps improve, and capacity for voltage regulation). A UPHS plant would be powered by either a coal-fired or nuclear baseload plant. The economic capacity of a UPHS plant would be in the range of 1000 to 3000 MW. This storage level is compatible with the load-velocity requirements of a greater metropolitan area with population of 1 million or more.

  20. 加装减载器的有杆抽油系统的平衡调节%Balance Adjustment of Sucker-rod Pumping System with Load Reducer

    Institute of Scientific and Technical Information of China (English)

    孟亚; 王金东; 于振东; 赵海洋

    2012-01-01

    Load reducer is a subsurface tool in the oil well. The load reducer can reduce sucker rod stress and polished rod load of pumping unit horse head by hydraulic pressure. The power charac-teristics and the balance of sucker-rod pumping system were changed with the reduced force pro-duced by the load reducer. According to the system motion law and the balance principle,the pum-ping system and the counter weight was analyzed with theory. The theoretical calculation combi-ning with the actual working condition, the system balance was adjusted by the result of numerical analysis again. As a result,the energy consumption of rod pumping system is reduced,the produc-tion cost is saved and the economic efficiency is improved.%减载器是采油井内配置的一种井下工具,可以通过自身产生的液压反馈力来降低抽油机驴头悬点载荷和抽油杆应力.加装减载器后,使有杆抽油系统的动力特性发生改变,原有系统平衡被打破.根据有杆抽油系统运动规律和平衡准则,对抽油系统及平衡重力进行分析.将理论计算与实际工况相结合,通过数值分析计算,对系统平衡进行调节,使有杆抽油系统能耗降低,达到节约生产成本、提高经济效益的目的.

  1. Penis Pump

    Science.gov (United States)

    ... claim that they can be used to increase penis size, but there's no evidence that they work for ... circumstances, using a penis pump might help your penis maintain its natural size and shape after prostate surgery or if you ...

  2. Energy saving by reducing the diameter of the impeller for water pumping in the dilution stage of honey in alcohol production. Distillery "Paradise."

    Directory of Open Access Journals (Sweden)

    Edelvy Bravo Amarante

    2014-06-01

    Full Text Available The sugar industry is a big consumer of the resource water in all its processes, including the alcohol production industry, one of the derivatives of its main process. Associated to water consumption there are important energetic expenses mainly for the necessity of using electro-pumps for its transfer. In the alcohol production the highest values of water consumed are concentrated in the fermentation stage. In the industry, object of study the highest consumptions are associated to the molasses dilution stage in alcohol production. This is the reason why this investigation is developed with the objective of assessing the water pumping system in the dilution stage in the distillery "Paradise", located in Sancti Spiritus, Cuba. As a result of this analysis it is proposed the reduction of the diameter of the pump impeller, it would make possible to save 38 249 kW-h per year, equivalent to $ 8 315, 67 per year.

  3. USING CABLE SUSPENDED SUBMERSIBLE PUMPS TO REDUCE PRODUCTION COSTS TO INCREASE ULTIMATE RECOVERY IN THE RED MOUNTAIN FIELD IN SAN JUAN BASIN REGION

    Energy Technology Data Exchange (ETDEWEB)

    Don L. Hanosh

    2004-01-01

    A joint venture between Enerdyne LLC, a small independent oil and gas producer, and Pumping Solutions Inc., developer of a low volume electric submersible pump, suspended from a cable, both based in Albuquerque, New Mexico, has re-established marginal oil production from the Red Mountain Oil Field, located in the San Juan Basin, New Mexico by working over 17 existing wells and installing submersible pumps. The project was funded through a cooperative 50% cost sharing agreement between Enerdyne LLC and the National Energy Technology Laboratory (NETL), United States Department of Energy, executed on April 16, 2003. The total estimated cost for this first phase of the agreement was $386,385.00 as detailed in Phase I Authorization For Expenditure (AFE). This report describes the tasks performed, the results, and conclusions for the first phase (Phase I) of the cooperative agreement.

  4. Influence of frontal cyclones evolution on the 2009 (Ekman and 2010 (Franklin Loop Current Eddy detachment events

    Directory of Open Access Journals (Sweden)

    Y. S. Androulidakis

    2014-07-01

    Full Text Available The anticyclonic Loop Current Eddy (LCE shedding events are strongly associated with the evolution of Loop Current Frontal Eddies (LCFEs over the eastern Gulf of Mexico (GoM. A numerical simulation, in tandem with in situ measurements and satellite data, was used to investigate the Loop Current (LC evolution and the surrounding LCFEs formation, structure, growth and migration during the Eddy Ekman and Eddy Franklin shedding events in the summers of 2009 and 2010, respectively. During both events, Northern GoM LCFEs appeared vertically coherent to at least 1500 m in temperature observations. They propagated towards the base of the LC where, together with the migration of Campeche Bank eddies from south of the LC, contributed to its "necking down". Growth of Campeche Bank LCFEs involved in Eddy Franklin was partially attributed to Campeche Bank waters following upwelling events. Slope processes associated with such upwelling include offshore exports of high positive vorticity that may trigger cyclone formation and growth. The advection and growth of LCFEs, originating from the northern and southern GoM, and their interaction with the LC over the LCE detachment area favor shedding conditions and may lead to the final separation of the LCE.

  5. Pulsed differential pumping system

    Energy Technology Data Exchange (ETDEWEB)

    Antipov, G.N.; Bagautdinov, F.A.; Rybalov, S.V.

    1985-06-01

    A pulsed differential pumping system is described for extracting an electron beam from a shaping region at a pressure of 10/sup -5/ torr into a volume with a pressure of 10-100 torr. A fast valve is used with appropriate geometrical parameters to reduce the length of the outlet channel considerable while increasing its diameter. Test results are given. The pumping system has two sections which communicate one with the other and with the volume at the elevated pressure which is produced by gasdynamic nozzles.

  6. A theoretical, two-layer, reduced-gravity model for descending dense water flow on continental shelves/slopes

    Science.gov (United States)

    Wang, Jia; Ikeda, Moto; Saucier, Francois J.

    2003-05-01

    A theoretical, two-layer, reduced-gravity model for descending dense water flow on continental shelves/slopes has been developed to investigate the dynamics of bottom dense water plumes. The model is nonsteady state and includes vertical viscosity, the Coriolis force, and bottom friction. An integral solution rather than a perfect analytical expression is derived and, thus, the Simpson's 1/3 rule to approximate the integral is applied. At the very bottom, the dense water plume moves about 45° to the right (left) in the Northern (Southern) Hemisphere, looking downslope. From the bottom, the velocity vector rotates anticyclonically upward, indicating a bottom Ekman spiral that mimics the atmospheric Ekman boundary layer. The dense water within the bottom Ekman layer obeys a three-force balance, while the dense water above the bottom Ekman layer is governed by a two-force balance, which is a geostrophic flow with superimposed cycloidal inertial oscillations oriented from about 25° to 140° to the right (left) of the downslope direction in the Northern (Southern) Hemisphere. The transport within the bottom Ekman layer is directed about 60-70° to the right (left) of the downslope direction in the Northern (Southern) Hemisphere, forming an offshore (cross-isobath) transport in the absence of eddy flux and wind-forcing. The ratio of offshore transport to alongshore transport within the bottom Ekman layer is about 0.19 (19%), while the ratio above the bottom Ekman layer (i.e., geostrophic layer of the dense water) is only 3% (negligible compared to its alongshore transport), which, however, is equivalent in magnitude to its counterpart in the bottom Ekman layer if O(DE/h) ˜ 0.1 (where DE is the bottom Ekman layer thickness and h is the dense water layer thickness). In other words, the bottom Ekman layer and the geostrophic (dense) layer contribute equivalent dense water offshore (each contributes 50%). The magnitude of the descending dense water velocity depends

  7. Using Cable Suspended Submersible Pumps to Reduce Production Costs to Increase Ultimate Recovery in the Red Mountain Field of the San Juan Basin Region

    Energy Technology Data Exchange (ETDEWEB)

    Don L. Hanosh

    2006-08-15

    A joint venture between Enerdyne LLC, a small independent oil and gas producer, and Pumping Solutions Inc., developer of a low volume electric submersible pump, suspended from a cable, both based in Albuquerque, New Mexico, has re-established marginal oil production from Red Mountain Oil Field, located in the San Juan Basin, New Mexico by working over 17 existing wells, installing cable suspended submersible pumps ( Phase I ) and operating the oil field for approximately one year ( Phase II ). Upon the completion of Phases I and II ( Budget Period I ), Enerdyne LLC commenced work on Phase III which required additional drilling in an attempt to improve field economics ( Budget Period II ). The project was funded through a cooperative 50% cost sharing agreement between Enerdyne LLC and the National Energy Technology Laboratory (NETL), United States Department of Energy, executed on April 16, 2003. The total estimated cost for the two Budget Periods, of the Agreement, was $1,205,008.00 as detailed in Phase I, II & III Authorization for Expenditures (AFE). This report describes tasks performed and results experienced by Enerdyne LLC during the three phases of the cooperative agreement.

  8. Coherent optical pumping of semiconductor lasers

    Energy Technology Data Exchange (ETDEWEB)

    Pfister, M.; Dupertuis, M.A. [Inst. de Micro- et Optoelectronique, Lausanne (Switzerland). Dept. de Physique

    1995-01-01

    The influence of coherent optical pumping in semiconductor lasers is investigated theoretically. In particular the mathematical conditions under which an optically pumped system behaves like an electrically (incoherently) pumped system are derived. The authors show that it is practically impossible to reach the interesting regime where coherent effects are important because of the inherent constraints to absorb photons at the pump frequency and to reach threshold gain at the lasing frequency. The effects of changing the temperature and of reduced dimensionality are discussed.

  9. Pumps; Pumpen

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, H. [Gesellschaft fuer Praktische Energiekunde e.V., Muenchen (Germany). Forschungsstelle fuer Energiewirtschaft; Hellriegel, E. [Gesellschaft fuer Praktische Energiekunde e.V., Muenchen (Germany). Forschungsstelle fuer Energiewirtschaft; Pfitzner, G. [Gesellschaft fuer Praktische Energiekunde e.V., Muenchen (Germany). Forschungsstelle fuer Energiewirtschaft

    1994-11-01

    The technical features of commercial pump types are described with regard to their technical, energy-related and economic parameters, and characteristic data are presented in the form of data sheets. This is to provide a basis for a comparative assessment of different technologies and technical variants. The chapter `System specifications` describes the various fields of application of pumps and the resulting specific requirements. The design and function of the different pump types are described in `Technical description`. `System and plant description dscribes the design and adaptation of pumps, i.e. the adaptation of the plant data to the system requirements. `Data compilation` provides a survey of the types and systematics of the compiled data as well as a decision aid for selecting the pumps best suited to the various applications. The `Data sheet` section describes the structure and handling of the data sheets as well as the data contained therein. The data sheets are contained in the apapendix of this report. The section `General analysis` compares typical technical, energy-related and economic characteristics of the different pump types. This is to enable a rough comparison of pump types and to facilitate decisions. The chapter `Example` illustrates the use of the data sheets by means of a selected example. (orig./GL) [Deutsch] Die vorliegende Arbeit hat zum Ziel, Technik seriengefertigter und marktgaengiger Pumpen in typisierter Form hinsichtlich ihrer technischen, energetischen und wirtschaftlichen Parameter zu beschreiben und ihre charakteristischen Kennwerte in Datenblaettern abzubilden. Damit wird ein grundlegendes Instrument fuer die vergleichende Beurteilung unterschiedlicher Techniken bzw. Technikvarianten hinsichtlich energetischer und wirtschaftlicher Kriterien geschaffen. Im Abschnitt `Systemanforderungen` erfolgt die Beschreibung der einzelnen Anwendungsbereiche fuer Pumpen mit den speziellen daraus resultierenden Anforderungen. Der Aufbau und

  10. Types of Breast Pumps

    Science.gov (United States)

    ... Devices Consumer Products Breast Pumps Types of Breast Pumps Share Tweet Linkedin Pin it More sharing options ... used for feeding a baby. Types of Breast Pumps There are three basic types of breast pumps: ...

  11. High Temperature Thermoacoustic Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, H.; Spoelstra, S. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-07-15

    Thermoacoustic technology can provide new types of heat pumps that can be deployed in different applications. Thermoacoustic heat pumps can for example be applied in dwellings to generate cooling or heating. Typically, space and water heating makes up about 60% of domestic and office energy consumption. The application of heat pumps can contribute to achieve energy savings and environmental benefits by reducing CO2 and NOx emissions. This paper presents the study of a laboratory scale thermoacoustic-Stirling heat pump operating between 10C and 80C which can be applied in domestics and offices. The heat pump is driven by a thermoacoustic-Stirling engine. The experimental results show that the heat pump pumps 250 W of heat at 60C at a drive ratio of 3.6 % and 200 W at 80C at a drive ratio of 3.5 %. The performance for both cases is about 40% of the Carnot performance. The design, construction, and performance measurements of the heat pump will be presented and discussed.

  12. Importance of Ekman transport and gyre circulation change on seasonal variation of surface dissolved iron in the western subarctic North Pacific

    Science.gov (United States)

    Nakanowatari, Takuya; Nakamura, Tomohiro; Uchimoto, Keisuke; Nishioka, Jun; Mitsudera, Humio; Wakatsuchi, Masaaki

    2017-05-01

    Iron (Fe) is an essential nutrient for marine phytoplankton and it constitutes an important element in the marine carbon cycle in the ocean. This study examined the mechanisms controlling seasonal variation of dissolved Fe (dFe) in the western subarctic North Pacific (WSNP), using an ocean general circulation model coupled with a simple biogeochemical model incorporating a dFe cycle fed by two major sources (atmospheric dust and continental shelf sediment). The model reproduced the seasonal cycle of observed concentrations of dFe and macronutrients at the surface in the Oyashio region with maxima in winter (February-March) and minima in summer (July-September), although the simulated seasonal amplitudes are a half of the observed values. Analysis of the mixed-layer dFe budget indicated that both local vertical entrainment and lateral advection are primary contributors to the wintertime increase in dFe concentration. In early winter, strengthened northwesterly winds excite southward Ekman transport and Ekman upwelling over the western subarctic gyre, transporting dFe-rich water southward. In mid to late winter, the southward western boundary current of the subarctic gyre and the outflow from the Sea of Okhotsk also bring dFe-rich water to the Oyashio region. The contribution of atmospheric dust to the dFe budget is several times smaller than these ocean transport processes in winter. These results suggest that the westerly wind-induced Ekman transport and gyre circulation systematically influence the seasonal cycle of WSNP surface dFe concentration.

  13. Heat pumps for the home

    CERN Document Server

    Cantor, John

    2013-01-01

    In recent years, heat pumps have emerged as a promising new form of technology with a relatively low environmental impact. Moreover, they have presented householders with an opportunity to reduce their heating bills. Heat pumps can heat a building by 'pumping' heat from either the ground or the air outside: an intriguing process which utilizes principles that are somewhat analogous to those employed in the domestic refrigerator. Armed with the practical information contained in these pages, homeowners will have the necessary knowledge to take advantage of this potentially low-carbon t

  14. Drug delivery device including electrolytic pump

    KAUST Repository

    Foulds, Ian G.

    2016-03-31

    Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

  15. Water Pump Development for the EVA PLSS

    Science.gov (United States)

    Schuller, Michael; Kurwitz, Cable; Goldman, Jeff; Morris, Kim; Trevino, Luis

    2009-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design, fabricate, and test a preflight prototype pump for use in the Extravehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump will accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting noncondensable gas without becoming "air locked." The chosen pump design consists of a 28 V DC, brushless, sealless, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. Although the planned flight unit will use a sensorless motor with custom designed controller, the preflight prototype to be provided for this project incorporates Hall effect sensors, allowing an interface with a readily available commercial motor controller. This design approach reduced the cost of this project and gives NASA more flexibility in future PLSS laboratory testing. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES will simulate the vacuum environment in which the flight pump will operate. Testing will verify that the pump meets design requirements for range of flow rates, pressure rise, power consumption, working fluid temperature, operating time, and restart capability. Pump testing is currently

  16. Pump characteristics and applications

    CERN Document Server

    Volk, Michael

    2013-01-01

    Providing a wealth of information on pumps and pump systems, Pump Characteristics and Applications, Third Edition details how pump equipment is selected, sized, operated, maintained, and repaired. The book identifies the key components of pumps and pump accessories, introduces the basics of pump and system hydraulics as well as more advanced hydraulic topics, and details various pump types, as well as special materials on seals, motors, variable frequency drives, and other pump-related subjects. It uses example problems throughout the text, reinforcing the practical application of the formulae

  17. LMFBR with booster pump in pumping loop

    Science.gov (United States)

    Rubinstein, H.J.

    1975-10-14

    A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation.

  18. Heat pump technology

    CERN Document Server

    Von Cube, Hans Ludwig; Goodall, E G A

    2013-01-01

    Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

  19. Reciprocating Pump Systems for Space Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2004-06-10

    Small propellant pumps can reduce rocket hardware mass, while increasing chamber pressure to improve specific impulse. The maneuvering requirements for planetary ascent require an emphasis on mass, while those of orbiting spacecraft indicate that I{sub SP} should be prioritized during pump system development. Experimental efforts include initial testing with prototype lightweight components while raising pump efficiency to improve system I{sub SP}.

  20. Dry vacuum pumps

    Science.gov (United States)

    Sibuet, R.

    2008-05-01

    For decades and for ultimate pressure below 1 mbar, oil-sealed Rotary Vane Pumps have been the most popular solution for a wide range of vacuum applications. In the late 80ies, Semiconductor Industry has initiated the development of the first dry roughing pumps. Today SC applications are only using dry pumps and dry pumping packages. Since that time, pumps manufacturers have developed dry vacuum pumps technologies in order to make them attractive for other applications. The trend to replace lubricated pumps by dry pumps is now spreading over many other market segments. For the Semiconductor Industry, it has been quite easy to understand the benefits of dry pumps, in terms of Cost of Ownership, process contamination and up-time. In this paper, Technology of Dry pumps, its application in R&D/industries, merits over conventional pumps and future growth scope will be discussed.

  1. Opened Proton Pump Inhibitor Capsules Reduce Time to Healing Compared With Intact Capsules for Marginal Ulceration Following Roux-en-Y Gastric Bypass.

    Science.gov (United States)

    Schulman, Allison R; Chan, Walter W; Devery, Aiofe; Ryan, Michele B; Thompson, Christopher C

    2017-04-01

    Marginal ulceration, or ulceration at the gastrojejunal anastomosis, is a common complication of Roux-en-Y gastric bypass (RYGB). Acidity likely contributes to the pathophysiology, and proton pump inhibitors (PPIs) frequently are prescribed for treatment. However, patients with gastric bypass only have a small gastric pouch and rapid small-bowel transit, which limits the opportunity for capsule breakdown and PPI absorption. Soluble PPIs (open capsules [OCs]) might be absorbed more easily than intact capsules (ICs). We compared time to ulcer healing, number of endoscopic procedures, and use of health care for patients with marginal ulceration who received PPIs in OC vs IC form. We performed a retrospective study of 164 patients diagnosed with marginal ulceration who underwent RYGB at the Brigham and Women's Hospital from 2000 through 2015. Patients received high-dose PPIs and underwent repeat endoscopy every 3 months until ulcer healing was confirmed. We used time-to-event analysis with a Cox proportional hazards model to evaluate the association between mode of PPI administration and time to ulcer healing, in addition to Cox multivariate regression analysis. Total charge (procedural and maintenance) was determined by comparison of categorized charges incurred from time of ulcer diagnosis to resolution. The primary outcome was time to healing of marginal ulceration in RYGB patients receiving high-dose PPIs in OC vs IC form. A total of 162 patients were included (115 received OC and 49 received IC). All patients were followed up until ulcer healing was confirmed. The median time to ulcer healing was 91.0 days for the OC group vs 342.0 days for the IC group (P < .001). OC was the only independent predictor of time to ulcer healing (P < .001) when we controlled for known risk factors. The number of endoscopic procedures (P = .02) and overall health care utilization (P = .05) were lower in the OC than the IC group. Patients with marginal ulceration after RYGB who

  2. A straight path centrifugal blood pump concept in the Capiox centrifugal pump.

    Science.gov (United States)

    Kijima, T; Oshiyama, H; Horiuchi, K; Nogawa, A; Hamasaki, H; Amano, N; Nojiri, C; Fukasawa, H; Akutsu, T

    1993-07-01

    This article describes comparative studies of a newly developed "straight path" centrifugal pump (Capiox centrifugal pump) targeted for open-heart surgery and circulatory support. A unique straight path design of the rotor was very effective in reducing the pump's rotational speed and prime volume. This pump was evaluated for hydraulics, hemolysis, depriming characteristics, cavitation, and heat generation. Two commercially available centrifugal pumps, the Biomedicus cone-type pump and the Sarns 3M impeller-type pump, were used as controls. The new pump required the lowest pump speed to produce the same flow rates under the same pressure loads and demonstrated the lowest hemolysis and the lowest temperature rise with the outlet clamped. The air volume required to deprime the new pump was one-third to one-half that for the other pumps, and no sign of cavitation was observed even if a small amount of air was introduced to the pump inlet under a negative pressure of 200 mm Hg.

  3. Centrifugal pump handbook

    CERN Document Server

    Pumps, Sulzer

    2010-01-01

    This long-awaited new edition is the complete reference for engineers and designers working on pump design and development or using centrifugal pumps in the field. This authoritative guide has been developed with access to the technical expertise of the leading centrifugal pump developer, Sulzer Pumps. In addition to providing the most comprehensive centrifugal pump theory and design reference with detailed material on cavitation, erosion, selection of materials, rotor vibration behavior and forces acting on pumps, the handbook also covers key pumping applications topics and operational

  4. Magnetic Heat Pump Containing Flow Diverters

    Science.gov (United States)

    Howard, Frank S.

    1995-01-01

    Proposed magnetic heat pump contains flow diverters for suppression of undesired flows. If left unchecked, undesired flows mix substantial amounts of partially heated and partially cooled portions of working fluid, effectively causing leakage of heat from heated side to cooled side. By reducing leakage of heat, flow diverters increase energy efficiency of magnetic heat pump, potentially offering efficiency greater than compressor-driven refrigerator.

  5. Magnetic Heat Pump Containing Flow Diverters

    Science.gov (United States)

    Howard, Frank S.

    1995-01-01

    Proposed magnetic heat pump contains flow diverters for suppression of undesired flows. If left unchecked, undesired flows mix substantial amounts of partially heated and partially cooled portions of working fluid, effectively causing leakage of heat from heated side to cooled side. By reducing leakage of heat, flow diverters increase energy efficiency of magnetic heat pump, potentially offering efficiency greater than compressor-driven refrigerator.

  6. [Off-pump coronary revascularization. Late survival].

    Science.gov (United States)

    Espinoza, Juan; Camporrontondo, Mariano; Vrancic, Mariano; Piccinini, Fernando; Camou, Juan; Navia, Daniel

    2017-01-01

    Although randomized clinical trials have compared the short-term results of coronary revascularization with on-pump vs. off-pump, the long-term survival effect of off-pump coronary surgery has not been analyzed. The aim of this study was to compare the long-term survival of patients with coronary surgery with off-pump technique. All patients that underwent coronary revascularization from November 1996 to March 2015 were included (n = 4687). We analyzed the long-term survival and the incidence of cardiac events between patients who received off-pump coronary revascularization (n = 3402) against those revascularized with on-pump technique (n = 1285). The primary endpoint was defined as death from any cause. To reduce potential biases, risk-adjusted analysis was performed (propensity score). In-hospital mortality and during follow-up (10 years) for both groups were analyzed. The overall hospital mortality was 3.1%. A statistically significant difference between groups in favor of off-pump surgery was observed (2.3% vs. 5.2%, p < 0.0001). In the survival analysis, off-pump surgery proved to have similar long-term survival as on-pump surgery (off-pump vs. on-pump: 77.9% ± 1.2% vs. 80.2% ± 1.3%, p log rank = 0.361); even in the adjusted survival analysis (84.2% ± 2.9% vs. 80.3% ± 2.4%, p = 0.169). In conclusion, off-pump coronary surgery was associated with lower in-hospital mortality; and it was not associated with increased long-term survival compared with on-pump surgery.

  7. Alternative backing up pump for turbomolecular pumps

    Science.gov (United States)

    Myneni, Ganapati Rao

    2003-04-22

    As an alternative to the use of a mechanical backing pump in the application of wide range turbomolecular pumps in ultra-high and extra high vacuum applications, palladium oxide is used to convert hydrogen present in the evacuation stream and related volumes to water with the water then being cryo-pumped to a low pressure of below about 1.e.sup.-3 Torr at 150.degree. K. Cryo-pumping is achieved using a low cost Kleemenco cycle cryocooler, a somewhat more expensive thermoelectric cooler, a Venturi cooler or a similar device to achieve the required minimization of hydrogen partial pressure.

  8. An improved charge pump with suppressed charge sharing effect

    Directory of Open Access Journals (Sweden)

    Na Bai

    2013-09-01

    Full Text Available A differential charge pump with reduced charge sharing effect is presented. The current-steering topology is adopted for fast switching. A replica charge pump is added to provide a current path for the complementary branch of the master charge pump in the current switching. Through the replica charge pump, the voltage at the complementary node of the master charge pump keeps stable during switching, and the dynamic charge sharing effect is avoided. Apply the charge pump to a 4.8 GHz band integer-N PLL, the measured reference spur is -49.7dBc with a 4-MHz reference frequency.

  9. Effect of pumping chamber on performance of non-overload centrifugal pump

    Institute of Scientific and Technical Information of China (English)

    谷云庆; 吴登昊; 牟介刚; 蒋兰芳; 代东顺; 施瀚昱; 郑水华

    2015-01-01

    In order to specify the characteristics of un-overloaded centrifugal pumps, the IH100-65-200 pump was chosen as the model pump. Different calculation models for centrifugal pumps were established under different pumping chamber sectional parameters. In the numerical simulation of the centrifugal pumps flow field, the shaft power, head, efficiency, and the changes of the internal flow field under different sectional areas and sectional shapes were studied with the RNGk−εturbulence model, and the influence of the pumping chamber section characteristics of the non-overloaded centrifugal pumps were analyzed. The results show that sectional areas have a significant impact on the non-overload characteristics of centrifugal pumps. The shaft power and head of centrifugal pump are increasing with a lager sectional area, by which the gradient of head curves decreases. The efficiency is improved under a large flow rate condition, but the head and the efficiency are reduced at a small flow rate. It is also observed that the sectional shapes have less influence on the shaft power, the hydraulic performance and flow field characteristics of a centrifugal pump.

  10. Large electromagnetic pumps. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Kilman, G.B.

    1976-01-01

    The development of large electromagnetic pumps for the liquid metal heat transfer systems of fission reactors has progressed for a number of years. Such pumps are now planned for fusion reactors and solar plants as well. The Einstein-Szilard (annular) pump has been selected as the preferred configuration. Some of the reasons that electromagnetic pumps may be preferred over mechanical pumps and why the annular configuration was selected are discussed. A detailed electromagnetic analysis of the annular pump, based on slug flow, is presented. The analysis is then used to explore the implications of large size and power on considerations of electromagnetic skin effect, geometric skin effect and the cylindrical geometry.

  11. Clinical use of centrifugal pumps and the roller pump in open heart surgery: a comparative evaluation.

    Science.gov (United States)

    Yoshikai, M; Hamada, M; Takarabe, K; Okazaki, Y; Ito, T

    1996-06-01

    Centrifugal pumps have been used widely as the main pump in open heart surgery to reduce damage to blood elements and to reduce the activation of the coagulation system. The purpose of this study was the evaluation and comparison of the effects of two types of centrifugal pumps and of one type of roller pump on blood elements, the coagulation system, complements, and immunoglobulins. Two types of centrifugal pumps (Lifestream; St. Jude Medical, Chelmsford, Massachusetts; and BP-80: Medtronic, BioMedicus, Inc., Eden Prairie, Minnesota, U.S.A.) and one roller pump (Mera Co.) were used separately as the main pump for cardiopulmonary bypass (CPB) in 29 patients. Platelet counts, lactate dehydrogenase, antithrombin III, thrombin-antithrombin complex (TAT), complements (C3, C4, and CH50) and immunoglobulins G, A, and M values were measured before and after CPB and compared. Values, except those for TAT, showed no significant difference among the three groups. The TAT values increased less in each of the centrifugal pump groups than in the roller pump group. This finding suggests that thrombin synthesis might be suppressed by the use of a centrifugal pump.

  12. Pump element for a tube pump

    DEFF Research Database (Denmark)

    2011-01-01

    The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction rela...... to a part of the tube. The invention further relates to a method for creating a flow of a fluid within an at least partly flexible tube by means of a pump element as mentioned above.......The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction...... portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube...

  13. Pump for Saturated Liquids

    Science.gov (United States)

    Elliott, D. G.

    1986-01-01

    Boiling liquids pumped by device based on proven components. Expanding saturated liquid in nozzle and diverting its phases along separate paths in liquid/vapor separator raises pressure of liquid. Liquid cooled in process. Pump makes it unnecessary to pressurize cryogenic liquids in order to pump them. Problems of introducing noncondensable pressurizing gas avoided.

  14. PLT rotating pumped limiter

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, S.A.; Budny, R.V.; Corso, V.; Boychuck, J.; Grisham, L.; Heifetz, D.; Hosea, J.; Luyber, S.; Loprest, P.; Manos, D.

    1984-07-01

    A limiter with a specially contoured front face and the ability to rotate during tokamak discharges has been installed in a PLT pump duct. These features have been selected to handle the unique particle removal and heat load requirements of ICRF heating and lower-hybrid current-drive experiments. The limiter has been conditioned and commissioned in an ion-beam test stand by irradiation with 1 MW power, 200 ms duration beams of 40 keV hydrogen ions. Operation in PLT during ohmic discharges has proven the ability of the limiter to reduce localized heating caused by energetic electron bombardment and to remove about 2% of the ions lost to the PLT walls and limiters.

  15. Flow Characteristics of the PHTS Mechanical Pump in PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jung; Lee, Tae-Hoo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Hwi-Seob [CD-adapco, Seoul (Korea, Republic of)

    2014-10-15

    The PHTS (Primary Heat Transfer System) mechanical pump is one of the most important parts in the PGSFR. The objective of the PHTS pump is to circulate a sodium coolant to transfer the heat generated in the core to the IHTS (Intermediate Heat Transfer System). Therefore, it is important to verify the performance of the PHTS pump under various flow conditions. The flow inside the pump is a very complex multi-dimensional phenomenon that depends on the rotation speed of the pump, and the geometry of the impeller and diffuser. In particular, the pump performance and flow characteristics can be evaluated using a homologous curve represented by normalized variables of the head and torque. Using a homologous curve obtained by a real pump or model pump reduced by the same specific speed is reasonable, but the detailed design procedure about the prototype PHTS pump has not been completed at this point. In this study, the flow characteristics and homologous curve of the PHTS pump are evaluated by CFD. The flow characteristic of the PHTS pump is evaluated by the CFD. The head and torque are calculated at several flow rates and rotation speeds, and these values are substituted with normalized pump parameters. Also, the homologous head and torque curve is plotted using normalized pump parameters. This curve is used as the input of the safety analysis.

  16. Energy Savings Potential for Pumping Water in District Heating Stations

    Directory of Open Access Journals (Sweden)

    Ioan Sarbu

    2015-05-01

    Full Text Available In district heating stations, the heat carrier is circulated between the energy source and consumers by a pumping system. Fluid handling systems, such as pumping systems, are responsible for a significant portion of the total electrical energy use. Significant opportunities exist to reduce pumping energy through smart design, retrofitting, and operating practices. Most existing systems requiring flow control make use of bypass lines, throttling valves or pump speed adjustments. The most efficient of these options is pump speed control. One of the issues in using variable-speed pumping systems, however, is the total efficiency of the electric motor/pump arrangement under a given operating condition. This paper provides a comprehensive discussion about pump control in heating stations and analyzes the energy efficiency of flow control methods. Specific attention is also given to the selection of motor types, sizing and pump duty cycle. A comparative energy analysis is performed on the hot water discharge adjustment using throttling control valves and variable-speed drives in a district heating station constructed in Romania. To correlate the pumped flow rate with the heat demand and to ensure the necessary pressure using minimum energy, an automatic system has been designed. The performances of these control methods are evaluated in two practical applications. The results show that approximately 20%–50% of total pumping energy could be saved by using the optimal control method with variable-speed pumps. Additionally, some modernization solutions to reduce the environmental impact of heating stations are described.

  17. Development of liquid nitrogen Centrifugal Pump

    Energy Technology Data Exchange (ETDEWEB)

    Abe, M; Sagiyama, R; Tsuchiya, H [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Takayama, T [Institute for Molecular Science, National Institutes of Natural Sciences, 38 Nishigo-Naka, Myodaiji, Okazaki, Aichi 444-8585 (Japan); Torii, Y [OMNIX, 1-15-3 Nishishinjuku, Shinjuku, Tokyo, 160-0023 (Japan); Nakamura, M [YN Nakamura Ltd, 3-9-25 Ohjima, Koto, Tokyo, 136-0072 (Japan); Hoshino, Y [JECC TORISHA Co. Ltd, 2-8-52 Yoshinodai, Kawagoe-shi, Saitama, 350-0833 (Japan); Odashima, Y [Department of Basic Sciences, University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8902 (Japan)], E-mail: mirei@issp.u-tokyo.ac.jp

    2009-02-01

    Usually liquid nitrogen (LN{sub 2}) transfer from a container to a laboratory equipment takes place by applying pressure to the container to push out liquid or pouring liquid into the cryostat directly by lifting the container. In order to overcome inconvenience of pressuring or lifting containers, we have been developing the Liquid Nitrogen Centrifugal Pump of a small electric turbine pump. Significant advantages that both reducing time to fill LN{sub 2}and controlling the flow rate of liquid into the cryostat are obtained by introducing this pump. We have achieved the lift of about 800mm with the vessel's opening diameter of 28mm.

  18. Engine room cooling system using jet pump

    Energy Technology Data Exchange (ETDEWEB)

    Lim, J.W.; Lee, S.H. [Daewoo Heavy Industries Ltd. (Korea)

    2000-04-01

    Construction machinery includes an engine enclosure separated from a cooling system enclosure by a wall to reduce noise and advance cooling system performance. For this structure, however, the axial fan cannot be of benefit to the engine room, and so the temperature rise in the engine room makes several bad conditions. This paper proposes that hot air in engine room is evacuated by secondary pipe using jet pump. This paper demonstrates the structure and the effect of jet pump and useful guideline on design of area, length, and shape of secondary pipe to maximize the effect of jet pump. (author). 4 refs., 7 figs., 5 tabs.

  19. Detection of pump degradation

    Energy Technology Data Exchange (ETDEWEB)

    Greene, R.H.; Casada, D.A.; Ayers, C.W. [and others

    1995-08-01

    This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

  20. Energy Saving in a Water Supply Network by Coupling a Pump and a Pump As Turbine (PAT) in a Turbopump

    OpenAIRE

    Armando Carravetta; Lauro Antipodi; Umberto Golia; Oreste Fecarotta

    2017-01-01

    The management of a water distribution network (WDN) is performed by valve and pump control, to regulate both the pressure and the discharge between certain limits. The energy that is usually merely dissipated by valves can instead be converted and used to partially supply the pumping stations. Pumps used as turbines (PAT) can be used in order to both reduce pressure and recover energy, with proven economic benefits. The direct coupling of the PAT shaft with the pump shaft in a PAT-pump turbo...

  1. Detection of pump degradation

    Energy Technology Data Exchange (ETDEWEB)

    Casada, D. [Oak Ridge National Lab., TN (United States)

    1995-04-01

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous special vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Pump head and flow rate are also monitored, per code requirements. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition; advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  2. Optically pumped atoms

    CERN Document Server

    Happer, William; Walker, Thad

    2010-01-01

    Covering the most important knowledge on optical pumping of atoms, this ready reference is backed by numerous examples of modelling computation for optical pumped systems. The authors show for the first time that modern scientific computing software makes it practical to analyze the full, multilevel system of optically pumped atoms. To make the discussion less abstract, the authors have illustrated key points with sections of MATLAB codes. To make most effective use of contemporary mathematical software, it is especially useful to analyze optical pumping situations in the Liouville spa

  3. Champagne Heat Pump

    Science.gov (United States)

    Jones, Jack A.

    2004-01-01

    The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

  4. Resonance wave pumping: wave mass transport pumping

    Science.gov (United States)

    Carmigniani, Remi; Violeau, Damien; Gharib, Morteza

    2016-11-01

    It has been previously reported that pinching at intrinsic resonance frequencies a valveless pump (or Liebau pump) results in a strong pulsating flow. A free-surface version of the Liebau pump is presented. The experiment consists of a closed tank with a submerged plate separating the water into a free-surface and a recirculation section connected through two openings at each end of the tank. A paddle is placed at an off-centre position at the free-surface and controlled in a heaving motion with different frequencies and amplitudes. Near certain frequencies identified as resonance frequencies through a linear potential theory analysis, the system behaves like a pump. Particle Image Velocimetry (PIV) is performed in the near free surface region and compared with simulations using Volume of Fluid (VOF) method. The mean eulerian mass flux field (ρ) is extracted. It is observed that the flow is located in the vicinity of the surface layer suggesting Stokes Drift (or Wave Mass Transport) is the source of the pumping. A model is developped to extend the linear potential theory to the second order to take into account these observations. The authors would like to acknowledge the Gordon and Betty Moore Foundation for their generous support.

  5. FIELD TRIALS OF NEWLY DEVELOPED POSITIVE DISPLACEMENT SUBMERSIBLE PUMP

    Energy Technology Data Exchange (ETDEWEB)

    Rob Beard

    2003-10-01

    The purpose of this grant was to evaluate under real world conditions the performance of a new type of downhole pump, the hydraulically driven submersible diaphragm pump. This pump is supplied by Pumping Solutions Incorporated, Albuquerque NM. The original scope of the project was to install 10 submersible pumps, and compare that to 10 similar installations of rod pumps. As an operator, the system as tested was not ready for prime time, but has shown the ability to reduce costs, and increase production, if run times can be improved. The PSI group did improve the product and offered excellent service. The latest design appears to be much better, but more test data is needed to show short run life is not a problem. PSI and Beard Oil intend to continue testing the pump with non-government funding. The testing to date did not uncover any fundamental problems that would preclude the widespread use of this pump, and as an operator, I believe that with further improvement and testing, the pump can have a significant impact on stripper well costs. On the positive side, the pump was easy to run, was more power efficient then a rod pump, and is the only submersible that could handle the large quantities of solids typical of the production environment found at the Weber field and in CMB production. The product shows much promise for the future, and with continued design and testing, this type of submersible pump has the potential to become the standard of the industry.

  6. Custom Unit Pump Development for the EVA PLSS

    Science.gov (United States)

    Schuller, Michael; Kurwitz, Cable; Little, Frank; Oinuma, Ryoji; Larsen, Ben; Goldman, Jeff; Reinis, Filip; Trevino, Luis

    2010-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design and test a pre-flight prototype pump for use in the Extra-vehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump must accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting non-condensable gas without becoming air locked. The chosen pump design consists of a 28 V DC, brushless, seal-less, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES verified that the pump meets the design requirements for range of flow rates, pressure drop, power consumption, working fluid temperature, operating time, gas ingestion, and restart capability under both ambient and vacuum conditions. The pump operated at 40 to 240 lbm/hr flow rate, 35 to 100 oF pump temperature, and 5 to 10 psid pressure rise. Power consumption of the pump controller at the nominal operating point in both ambient and vacuum conditions was 9.5 W, which was less than the 12 W predicted. Gas ingestion capabilities were tested by injecting 100 cc of air into the fluid line; the pump operated normally throughout this test.

  7. Potential of the heat pump; Potenziale der Waermepumpe

    Energy Technology Data Exchange (ETDEWEB)

    Flade, F. [Bundesverband WaermePumpe (BWP) e.V., Muenchen (Germany)

    2005-07-01

    Heat pumps have been around for years. They are a mature and economically efficient heating technology which will reduce primary energy consumption and CO2 emissions quickly and sustainably. In 2002, 251,000 million l of heating oil and 289,000 million cubic metres of gas were consumed for heating in Germany, which might have been greatly reduced with heat pumps. At a seasonal performance factor of 4.5 as is common in groundwater and ground source heat pumps, heat pumps will produce 40 percent less CO2 than gas-fuelled high-efficiency boilers. At 'normal' values of 3.5 which are more or less standard values for air-to-water heat pumps, CO2 emissions will be reduced by 30 percent. The heat pump is an ecologically effective and economically efficient alternative to conventional heating systems. (orig.)

  8. Procesamiento emocional en maltratadores de género mediante el Test de Expresiones Faciales de Ekman y la Tarea Stroop Emocional

    Directory of Open Access Journals (Sweden)

    Natalia Bueso-Izquierdo

    2015-01-01

    Full Text Available La investigación actual en el campo de la violencia de pareja es escasa en lo que se re - fiere al papel del procesamiento emocional de los maltratadores. Sin embargo, ningún estudio ha investigado en la misma muestra la capacidad de reconocer las emociones y la influencia de las emociones en los aspectos atencionales. El objetivo de este estudio es investigar en una muestra de maltratadores la capacidad de reconocer las emociones de fotografías estandarizadas y analizar la interferencia de las palabras con contenido emocional en una tarea atencional. La muestra consistió en 90 hombres condenados por violencia de pareja y 77 hombres condenados por otros delitos. Se evaluaron las caracte - rísticas sociodemográficas asociadas a nuestra muestra y el procesamiento emocional de las expresiones faciales con la prueba de Ekman y la Tarea Stroop Emocional, diseñada específicamente para evaluar el procesamiento emocional en situaciones de violencia contra la pareja. Los resultados mostraron un mejor reconocimiento emocional de los maltratadores en las emociones faciales de enfado y sorpresa. Para el procesamiento de palabras con contenido emocional, las diferencias no fueron estadísticamente significa - tivas. © 2015, Fundación Universitaria Konrad Lorenz. Publicado por Elsevier España, S.L.U. Este es un artículo de acceso abierto distribuido bajo los términos de la Licencia Creative Commons CC BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/4.0/.

  9. Demanding pump power; Krevende pumpekraft

    Energy Technology Data Exchange (ETDEWEB)

    Lie, Oeyvind

    2011-07-01

    The potential for pump power in Norway is huge, but it is difficult to exploit it. Norway has some pumping plants, but these are built for seasonal pumping (pumping up to the magazine in the summer, and production in the winter). Pump power plants for short periods do not exist in Norway. (AG)

  10. Pump element for a tube pump

    DEFF Research Database (Denmark)

    2011-01-01

    relative to the rod element so as to allow for a fluid flow in the tube through the first valve member, along the rod element, and through the second valve member. The tube comprises an at least partly flexible tube portion between the valve members such that a repeated deformation of the flexible tube...... portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube...... pump as mentioned above, thereby acting to generate a fluid flow through the tube upon repeated deformation of the tube between the two valve members. The pump element may comprise a connecting part for coupling to another tube and may comprise a sealing part establishing a fluid tight connection...

  11. Reduced volume but increased training intensity elevates muscle Na+-K+ pump alpha1-subunit and NHE1 expression as well as short-term work capacity in humans

    DEFF Research Database (Denmark)

    Iaia, F. Marcello; Thomassen, Martin; Kolding, Helle;

    2008-01-01

    by 30-s sprint runs three to four times a week, whereas CON continued the endurance training ( approximately 45 km/wk). After the 4-wk sprint period, the expression of the muscle Na(+)-K(+) pump alpha(1)-subunit and Na(+)/H(+)-exchanger isoform 1 was 29 and 30% higher (P ... pulmonary maximum oxygen uptake and 10-k time were unchanged. No changes in CON were observed. The present data suggest a role of the Na(+)-K(+) pump in the control of K(+) homeostasis and in the development of fatigue during repeated high-intensity exercise. Furthermore, performance during intense exercise...

  12. Energy efficient ammonia heat pump. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, Claus; Pijnenburg, B.; Schumann Grindorf, H. [Danish Technological Institute, Aarhus (Denmark); Christensen, Rolf [Alfa Laval, Lund (Sweden); Rasmussen, Bjarne D. [Grundfos, Bjerringbro (Denmark); Gram, S.; Fredborg Jakobsen, D. [Svedan Industri Koeleanlaeg, Greve (Denmark)

    2013-09-15

    The report describes the development of a highly effective ammonia heat pump. Heat pumps play an increasingly important role in the search for more effective use of energy in our society. Highly efficient heat pumps can contribute to reduced energy consumption and improved economy of the systems which they are a part of. An ammonia heat pump with high pressure reciprocating compressor and a novel split condenser was developed to prove potential for efficiency optimization. The split of the condenser in two parts can be utilized to obtain smaller temperature approaches and, thereby, improved heat pump efficiency at an equal heat exchanger area, when compared to the traditional solution with separate condenser and de-superheater. The split condenser design can also be exploited for heating a significant share of the total heating capacity to a temperature far above the condensing temperature. Furthermore, the prototype heat pump was equipped with a plate type evaporator combined with a U-turn separator with a minimum liquid height and a liquid pump with the purpose of creating optimum liquid circulation ratio for the highest possible heat transfer coefficients at the lowest possible pressure drop. The test results successfully confirmed the highest possible efficiency; a COP of 4.3 was obtained when heating water from 40 deg. C to 80 deg. C while operating with evaporating/condensing temperatures of +20 deg C/+73 deg C. (Author)

  13. Polarization-insensitive fiber optical parametric amplifier based on polarization diversity technique with dual parallel pumps

    Institute of Scientific and Technical Information of China (English)

    YIN Lu; SANG Xin-zhu; ZHANG Qi; XIN Xiang-jun; YU Chong-xiu; Da-xiong

    2011-01-01

    By analyzing the principle of dual-pump parametric amplification and the polarization dependent gain of fiber optical parametric amplifier (FOPA), a polarization-insensitive FOPA based on polarization-diversity technique with dual parallel pumps is presented. The performances of polarization-insensitivity, gain and BER are theoretically analyzed and numerically simulated by comparing the proposed scheme with parallel pump solution and orthogonal pump solution. The presented solution can reduce the complexity of state of polarization (SoP) of pumps.

  14. New turbomolecular pump with central opening for free axial access

    CERN Document Server

    Mokler, P H

    2004-01-01

    Standard turbomolecular pumps show typically one annular active intake area on the high vacuum flange side (single-flow pumps). The central circular part of the inlet of the compressor turbine is blind for pumping. The new design proposes a central opening of a turbomolecular pump all along the axis. This central bore can be used e.g. for mounting of feed throughs, manipulators, windows or for coupling to further vacuum devices, in particular also for enclosing tube-like vacuum systems. This design allows a multi-use of a pumping port at a vacuum vessel without reducing there the pumping speed. Moreover, the new design is ideal for axial or radial differential pumping arrangements as e.g. needed for all gas jet like set-ups or other pressure reduction stages.

  15. A Shocking New Pump

    Science.gov (United States)

    2000-01-01

    Hydro Dynamics, Inc. received a technical helping hand from NASA that made their Hydrosonic Pump (HPump) a reality. Marshall engineers resolved a bearing problem in the rotor of the pump and recommended new bearings, housings and mounting hardware as a solution. The resulting HPump is able to heat liquids with greater energy efficiency using shock waves to generate heat.

  16. Water Treatment Technology - Pumps.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on pumps provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pumps in plant and distribution systems, pump…

  17. Review of magnetohydrodynamic pump applications

    National Research Council Canada - National Science Library

    Al-Habahbeh, O.M; Al-Saqqa, M; Safi, M; Abo Khater, T

    2016-01-01

    Magneto-hydrodynamic (MHD) principle is an important interdisciplinary field. One of the most important applications of this effect is pumping of materials that are hard to pump using conventional pumps...

  18. Similar Efficacy of Proton-Pump Inhibitors vs H2-Receptor Antagonists in Reducing Risk of Upper Gastrointestinal Bleeding or Ulcers in High-Risk Users of Low-Dose Aspirin.

    Science.gov (United States)

    Chan, Francis K L; Kyaw, Moe; Tanigawa, Tetsuya; Higuchi, Kazuhide; Fujimoto, Kazuma; Cheong, Pui Kuan; Lee, Vivian; Kinoshita, Yoshikazu; Naito, Yuji; Watanabe, Toshio; Ching, Jessica Y L; Lam, Kelvin; Lo, Angeline; Chan, Heyson; Lui, Rashid; Tang, Raymond S Y; Sakata, Yasuhisa; Tse, Yee Kit; Takeuchi, Toshihisa; Handa, Osamu; Nebiki, Hiroko; Wu, Justin C Y; Abe, Takashi; Mishiro, Tsuyoshi; Ng, Siew C; Arakawa, Tetsuo

    2017-01-01

    It is not clear whether H2-receptor antagonists (H2RAs) reduce the risk of gastrointestinal (GI) bleeding in aspirin users at high risk. We performed a double-blind randomized trial to compare the effects of a proton pump inhibitor (PPI) vs a H2RA antagonist in preventing recurrent upper GI bleeding and ulcers in high-risk aspirin users. We studied 270 users of low-dose aspirin (≤325 mg/day) with a history of endoscopically confirmed ulcer bleeding at 8 sites in Hong Kong and Japan. After healing of ulcers, subjects with negative results from tests for Helicobacter pylori resumed aspirin (80 mg) daily and were assigned randomly to groups given a once-daily PPI (rabeprazole, 20 mg; n = 138) or H2RA (famotidine, 40 mg; n = 132) for up to 12 months. Subjects were evaluated every 2 months; endoscopy was repeated if they developed symptoms of upper GI bleeding or had a reduction in hemoglobin level greater than 2 g/dL and after 12 months of follow-up evaluation. The adequacy of upper GI protection was assessed by end points of recurrent upper GI bleeding and a composite of recurrent upper GI bleeding or recurrent endoscopic ulcers at month 12. During the 12-month study period, upper GI bleeding recurred in 1 patient receiving rabeprazole (0.7%; 95% confidence interval [CI], 0.1%-5.1%) and in 4 patients receiving famotidine (3.1%; 95% CI, 1.2%-8.1%) (P = .16). The composite end point of recurrent bleeding or endoscopic ulcers at month 12 was reached by 9 patients receiving rabeprazole (7.9%; 95% CI, 4.2%-14.7%) and 13 patients receiving famotidine (12.4%; 95% CI, 7.4%-20.4%) (P = .26). In a randomized controlled trial of users of low-dose aspirin at risk for recurrent GI bleeding, a slightly lower proportion of patients receiving a PPI along with aspirin developed recurrent bleeding or ulcer than of patients receiving an H2RA with the aspirin, although this difference was not statistically significant. ClincialTrials.gov no: NCT01408186. Copyright © 2017 AGA

  19. Proton-pump inhibitors are associated with a reduced risk for bleeding and perforated gastroduodenal ulcers attributable to non-steroidal anti-inflammatory drugs : a nested case-control study

    NARCIS (Netherlands)

    Vonkeman, Harald E; Fernandes, Robert W; van der Palen, Job; van Roon, Eric N; van de Laar, Mart A F J

    2007-01-01

    Treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is hampered by gastrointestinal ulcer complications, such as ulcer bleeding and perforation. The efficacy of proton-pump inhibitors in the primary prevention of ulcer complications arising from the use of NSAIDs remains unproven. Selectiv

  20. [Hemodynamic analysis of a centrifugal blood pump].

    Science.gov (United States)

    Wang, Yang; Yang, Ming; Xu, Zihao; Zhuang, Xiaoqi; Li, Qilei; Xu, Liang

    2015-01-01

    This paper built the mathematical model of a centrifugal blood pump, which was designed by ourselves, combined it with that of the human cardiovascular system and simulated the coupling system using Matlab. Then we set up the experiment platform, linked the blood pump to mock human cardiovascular system in case of three-stage heart failure, and measured aortic pressure and flow under different speed. The comparison between experiment results and simulation results not only indicates the coupling model is correct and the blood pump works well, but also shows that with the increase of blood pump speed, the pulsation of aortic pressure and flow will be reduced, this situation will affect the structure and function of blood vessels.

  1. Advanced performance of small diaphragm vacuum pumps through the use of mechatronics

    Science.gov (United States)

    Lachenmann, R.; Dirscherl, J.

    Oil-free diaphragm vacuum pumps have proven to be the best way in vacuum generation for the chemical laboratory and they also find increasing use as backing pumps for modern wide-range turbo molecular pumps. The majority of vacuum pumps in practical use pump only a rather small percentage of their lifetime at full gas load. A pump backing a turbo molecular pump does not have to pump a significant gas load when the high-vacuum pump is running at ultimate vacuum pressure. Also, for a vacuum distillation the vacuum pump has to operate at full speed only at the beginning to lower the pressure inside the system to a vacuum level where evaporation starts. In a rather leak-tight system the distillation process continues by evaporating from the hot liquid and condensing at the cold condenser without the need of a mechanical vacuum pump. Rotational speed controlled diaphragm pumps are now available through progress in mechatronics and offer high pumping speed capability for fast pump-down cycles and precise pressure control for distillations. At low gas load the rotational speed can be reduced, improving maintenance intervals, power consumption, noise, vibration and - surprisingly - also ultimate pressure. The different behaviour in pumping speed and ultimate pressure of rotational speed controlled diaphragm pumps in comparison to constant-speed pumps is related to the mechanical properties of the valves and gas dynamics .

  2. Pumping machinery theory and practice

    CERN Document Server

    Badr, Hassan M

    2014-01-01

    Pumping Machinery Theory and Practice comprehensively covers the theoretical foundation and applications of pumping machinery. Key features: Covers characteristics of centrifugal pumps, axial flow pumps and displacement pumpsConsiders pumping machinery performance and operational-type problemsCovers advanced topics in pumping machinery including multiphase flow principles, and two and three-phase flow pumping systemsCovers different methods of flow rate control and relevance to machine efficiency and energy consumptionCovers different methods of flow rate control and relevance to machine effi

  3. Pumps used as turbines power recovery, energy efficiency, CFD analysis

    OpenAIRE

    Bogdanović-Jovanović Jasmina B.; Milenković Dragica R.; Svrkota Dragan M.; Bogdanović Božidar; Spasić Živan T.

    2014-01-01

    As the global demand for energy grows, numerous studies in the field of energy efficiency are stimulated, and one of them is certainly the use of pumps in turbine operating mode. In order to reduce time necessary to determine pump characteristic in turbine operating mode problem was studied by computational fluid dynamics approach. The paper describes various problems faced during modeling (pump and turbine mode) and the approaches used to resolve the probl...

  4. Fluidized Bed Air-to-Air Heat Pump Evaporator Evaluation.

    Science.gov (United States)

    1983-07-01

    Frost formation of air-to-air heat pump evaporator surfaces reduces unit efficiency and restricts application. The use of a fluidized bed heat...exchanger as an air-to- heat pump evaporator was investigated to determine if frost accumulation could be eliminated. Experimental investigations were...evaluated, with no practical solution being developed. The use of a fluidized bed heat exchanger for air-to-air heat pump evaporators was determined not feasible. (Author)

  5. Solar Assisted Ground Source Heat Pump Performance in Nearly Zero Energy Building in Baltic Countries

    National Research Council Canada - National Science Library

    Karolis Januševičius; Giedrė Streckienė

    2013-01-01

    .... Heat pump systems are a widespread solution to reduce energy use. A combination of heat pump and solar thermal collectors helps to meet standard requirements and increases the share of renewable energy use in total energy balance of country...

  6. Trade-Offs in Improving Biofuel Tolerance Using Combinations of Efflux Pumps.

    Science.gov (United States)

    Turner, William J; Dunlop, Mary J

    2015-10-16

    Microbes can be engineered to produce next-generation biofuels; however, the accumulation of toxic biofuels can limit yields. Previous studies have shown that efflux pumps can increase biofuel tolerance and improve production. Here, we asked whether expressing multiple pumps in combination could further increase biofuel tolerance. Pump overexpression inhibits cell growth, suggesting a trade-off between biofuel and pump toxicity. With multiple pumps, it is unclear how the fitness landscape is impacted. To address this, we measured tolerance of Escherichia coli to the biojet fuel precursor α-pinene in one-pump and two-pump strains. To support our experiments, we developed a mathematical model describing toxicity due to biofuel and overexpression of pumps. We found that data from one-pump strains can accurately predict the performance of two-pump strains. This result suggests that it may be possible to dramatically reduce the number of experiments required for characterizing the effects of combined biofuel tolerance mechanisms.

  7. Results of Investigations of Failures of Geothermal Direct Use Well Pumps

    Energy Technology Data Exchange (ETDEWEB)

    Culver, G.

    1994-12-01

    Failures of 13 geothermal direct-use well pumps were investigated and information obtained about an additional 5 pumps that have been in service up to 23 years, but have not failed. Pumps with extra long lateral and variable-speed drives had the highest correlation with reduced time in service. There appears to be at least circumstantial evidence that recirculation may be a cause of reduced pump life. If recirculation is a cause of pump failures, pump specifiers will need to be more aware of minimum flow conditions as well as maximum flow conditions when specifying pumps. Over-sizing pumps and the tendency to specify pumps with high flow and low Net Positive Suction Head (NPSH) could lead to increased problems with recirculation.

  8. Results of investigations of failures of geothermal direct-use well pumps

    Energy Technology Data Exchange (ETDEWEB)

    Culver, G.

    1994-12-01

    Failures of 13 geothermal direct-use well pumps were investigated and information obtained about an additional 5 pumps that have been in service up to 23 years, but have not failed. Pumps with extra long lateral and variable-speed drives had the highest correlation with reduced time in service. There appears to be at least circumstantial evidence that recirculation may be a cause of reduced pump life. If recirculation is a cause of pump failures, pump specifiers will need to be more aware of minimum flow conditions as well as maximum flow conditions when specifying pumps. Over-sizing pumps and the tendency to specify pumps with high flow and low Net Positive Suction Head (NPSH) could lead to increased problems with recirculation.

  9. Nuclear-pumped lasers

    CERN Document Server

    Prelas, Mark

    2016-01-01

    This book focuses on Nuclear-Pumped Laser (NPL) technology and provides the reader with a fundamental understanding of NPLs, a review of research in the field, and exploration of large scale NPL system design and applications. Early chapters look at the fundamental properties of lasers, nuclear-pumping and nuclear reactions that may be used as drivers for nuclear-pumped lasers. The book goes on to explore the efficient transport of energy from the ionizing radiation to the laser medium and then the operational characteristics of existing nuclear-pumped lasers. Models based on Mathematica, explanations and a tutorial all assist the reader’s understanding of this technology. Later chapters consider the integration of the various systems involved in NPLs and the ways in which they can be used, including beyond the military agenda. As readers will discover, there are significant humanitarian applications for high energy/power lasers, such as deflecting asteroids, space propulsion, power transmission and mining....

  10. Absorption heat pump system

    Science.gov (United States)

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  11. High Voltage Charge Pump

    KAUST Repository

    Emira, Ahmed A.

    2014-10-09

    Various embodiments of a high voltage charge pump are described. One embodiment is a charge pump circuit that comprises a plurality of switching stages each including a clock input, a clock input inverse, a clock output, and a clock output inverse. The circuit further comprises a plurality of pumping capacitors, wherein one or more pumping capacitors are coupled to a corresponding switching stage. The circuit also comprises a maximum selection circuit coupled to a last switching stage among the plurality of switching stages, the maximum selection circuit configured to filter noise on the output clock and the output clock inverse of the last switching stage, the maximum selection circuit further configured to generate a DC output voltage based on the output clock and the output clock inverse of the last switching stage.

  12. Regenerative Hydride Heat Pump

    Science.gov (United States)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  13. Chiral brownian heat pump.

    Science.gov (United States)

    van den Broek, M; Van den Broeck, C

    2008-04-04

    We present the exact analysis of a chiral Brownian motor and heat pump. Optimization of the construction predicts, for a nanoscale device, frequencies of the order of kHz and cooling rates of the order of femtojoule per second.

  14. Chiral Brownian heat pump

    OpenAIRE

    Van Den Broek, Martijn; Van Den Broeck, Christian

    2007-01-01

    We present the exact analysis of a chiral Brownian motor and heat pump. Optimization of the construction predicts, for a nanoscale device, frequencies of the order of kHz and cooling rates of the order of femtojoule per second.

  15. Regenerative Hydride Heat Pump

    Science.gov (United States)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  16. Remotely Adjustable Hydraulic Pump

    Science.gov (United States)

    Kouns, H. H.; Gardner, L. D.

    1987-01-01

    Outlet pressure adjusted to match varying loads. Electrohydraulic servo has positioned sleeve in leftmost position, adjusting outlet pressure to maximum value. Sleeve in equilibrium position, with control land covering control port. For lowest pressure setting, sleeve shifted toward right by increased pressure on sleeve shoulder from servovalve. Pump used in aircraft and robots, where hydraulic actuators repeatedly turned on and off, changing pump load frequently and over wide range.

  17. Velocity selective optical pumping

    OpenAIRE

    Aminoff, C. G.; Pinard, M.

    1982-01-01

    We consider optical pumping with a quasi monochromatic tunable light beam, in the low intensity limit where a rate equation regime is obtained The velocity selective optical pumping (V.S.O.P.) introduces a correlation between atomic velocity and internal variables in the ground (or metastable) state. The aim of this article is to evaluate these atomic observables (orientation, alignment, population) as a function of velocity, using a phenomenological description of the relaxation effect of co...

  18. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  19. Pumping a playground swing.

    Science.gov (United States)

    Post, Auke A; de Groot, Gert; Daffertshofer, Andreas; Beek, Peter J

    2007-04-01

    In mechanical studies of pumping a playground swing, two methods of energy insertion have been identified: parametric pumping and driven oscillation. While parametric pumping involves the systematic raising and lowering of the swinger's center of mass (CM) along the swing's radial axis (rope), driven oscillation may be conceived as rotation of the CM around a pivot point at a fixed distance to the point of suspension. We examined the relative contributions of those two methods of energy insertion by inviting 18 participants to pump a swing from standstill and by measuring and analyzing the swing-swinger system (defined by eight markers) in the sagittal plane. Overall, driven oscillation was found to play a major role and parametric pumping a subordinate role, although the relative contribution of driven oscillation decreased as swinging amplitude increased, whereas that of parametric pumping increased slightly. Principal component analysis revealed that the coordination pattern of the swing-swinger system was largely determined (up to 95%) by the swing's motion, while correlation analysis revealed that (within the remaining 5% of variance) trunk and leg rotations were strongly coupled.

  20. Pump shaft failures - a compendium of case studies

    CSIR Research Space (South Africa)

    Bernt, F

    2001-04-01

    Full Text Available of failure. Pump shafts are generally exposed to the liquid being pumped either on a continual basis or at certain locations along the length of the shaft. Specialised sealing arrangements comprising sleeves and o-rings can be used to reduce the amount...

  1. Vacuum Pump System Optimization Saves Energy at a Dairy Farm

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-08-01

    In 1998, S&S Dairy optimized the vacuum pumping system at their dairy farm in Modesto, California. In an effort to reduce energy costs, S&S Dairy evaluated their vacuum pumping system to determine if efficiency gains and energy savings were possible.

  2. Antiplatelet agents and proton pump inhibitors – personalizing treatment

    Directory of Open Access Journals (Sweden)

    Eugene Lin

    2010-06-01

    Full Text Available Eugene Lin, Rajiv Padmanabhan, Majaz MoonisDepartment of Neurology, University of Massachusetts Medical School and UMass Memorial Medical Center, Worcester, Massachusetts, USAIntroduction: Antiplatelet therapy remains one of the cornerstones in the management of noncardioembolic ischemic stroke. However, a significant percentage of patients have concomitant gastroesophageal reflux or peptic ulcer disease that requires acid-reducing medications, the most powerful and effective being the proton pump inhibitors (PPIs. Antiplatelet efficacy, at least in vivo, and particularly for clopidogrel, has been shown to be reduced with concomitant proton pump inhibitor use. Whether this is clinically relevant is not clear from the limited studies available.Methods: We conducted an extensive review of studies available on Medline related to pharmacodynamic interactions between the antiplatelet medications and proton pump inhibitors as well as clinical studies that addressed this potential interaction.Results: Based on the present pharmacodynamic and clinical studies we did not find a significant interaction that would reduce the efficacy of antiplatelet agents with concomitant user of proton pump inhibitors.Conclusions: Patients on antiplatelet agents after a transient ischemic attack or ischemic stroke can safely use aspirin, and extended release dipyridamole/aspirin with proton pump inhibitors. Patients on clopidogrel may use other acid-reducing drugs besides proton pump inhibitors. In rare cases where proton pump inhibitors and clopidogrel have to be used concurrently, careful close monitoring for recurrent vascular events is required.Keywords: proton pump inhibitors, antiplatelet medications, clopidogrel, ischemic stroke, cardiovascular events

  3. Thermally Actuated Hydraulic Pumps

    Science.gov (United States)

    Jones, Jack; Ross, Ronald; Chao, Yi

    2008-01-01

    Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research

  4. Assessing variable speed pump efficiency in water distribution systems

    Directory of Open Access Journals (Sweden)

    A. Marchi

    2012-07-01

    Full Text Available Energy savings and greenhouse gas emission reductions are increasingly becoming important design targets in many industrial systems where fossil fuel based electrical energy is heavily utilised. In water distribution systems (WDSs a significant portion of operational cost is related to pumping. Recent studies have considered variable speed pumps (VSPs which aim to vary the operating point of the pump to match demand to pumping rate. Depending on the system characteristics, this approach can lead to considerable savings in operational costs. In particular, cost reductions can take advantage of the demand variability and can decrease energy consumption significantly. One of the issues in using variable speed pumping systems, however, is the total efficiency of the electric motor/pump arrangement under a given operating condition. This paper aims to provide a comprehensive discussion about the components of WDS that incorporate variable speed pumps (including electric motors, variable frequency drives and the pumps themselves to provide an insight of ways of increasing the system efficiency and hence to reduce energy consumption. In addition, specific attention is given to selection of motor types, sizing, duty cycle of pump (ratio of on-time and time period, losses due to installation and motor faults. All these factors affect the efficiency of motor drive/pump system.

  5. Assessing variable speed pump efficiency in water distribution systems

    Directory of Open Access Journals (Sweden)

    A. Marchi

    2012-03-01

    Full Text Available Energy savings and greenhouse gas emission reductions are increasingly becoming important design targets in many industrial systems where fossil fuel based electrical energy is heavily utilised. In water distribution systems (WDSs a significant portion of operational cost is related to pumping. Recent studies have considered variable speed pumps (VSPs which aim to vary the operating point of the pump to match demand to pumping rate. Depending on the system characteristics, this approach can lead to considerable savings in operational costs. In particular, cost reductions can take advantage of the demand variability and can decrease energy consumption significantly. One of the issues in using variable speed pumping systems, however, is the total efficiency of the electric motor/pump arrangement under a given operating condition. This paper aims to provide a comprehensive discussion about the components of WDS that incorporate variable speed pumps (including electric motors, inverters and the pumps themselves to provide an insight of ways of increasing the system efficiency and hence to reduce energy consumption. In addition, specific attention is given to selection of motor types, sizing, duty cycle of pump (ratio of on-time and time period, losses due to installation and motor faults. All these factors affect the efficiency of motor drive/pump system.

  6. Feasibility of a TinyPump system for pediatric CPB, ECMO, and circulatory assistance: hydrodynamic performances of the modified pump housing for implantable TinyPump.

    Science.gov (United States)

    Yokoyama, Naoyuki; Suzuki, Masaaki; Hoshi, Hideo; Ohuchi, Katsuhiro; Fujimoto, Tetsuo; Takatani, Setsuo

    2007-01-01

    The TinyPump is a miniature centrifugal blood pump with an extremely small priming volume of 5 ml, allowing blood transfusion free cardiopulmonary bypass as well as extracorporeal membrane oxygenation in pediatric patients. In this study, a new pump housing with the angled inlet port (25 degrees toward impeller center with respect to the flow axis) was designed to optimize the pump displaced volume and to extend the application of the TinyPump to implantable support The fluid dynamic performance analysis revealed that the head pressure losses increased from 3 to 17 mm Hg in comparison with straight port design as the pump rotational speed increased from 2,000 to 4,000 rpm. This was probably caused by perturbed flow patterns at the site of the inlet bent port area and streamline hitting the off-center of the impeller. No significant effect on pumping efficiency was observed because of modification in inlet port design. Modification in the inflow and outflow port designs together with the drive mechanism reduces the height of the pump system, including the motor, to 27 mm yielding the displaced volume of 68 ml in comparison with 40 mm of the paracorporeal system with the displaced volume of 105 ml. Further analysis in terms of hemolytic as well as antithrombogenic performance will be carried out to finalize the housing design for the implantable version of the TinyPump.

  7. Variations in battery life of a heart-lung machine using different pump speeds, pressure loads, boot material, centrifugal pump head, multiple pump usage, and battery age.

    LENUS (Irish Health Repository)

    Marshall, Cornelius

    2012-02-03

    Electrical failure during cardiopulmonary bypass (CPB) has previously been reported to occur in 1 of every 1500 cases. Most heart-lung machine pump consoles are equipped with built-in battery back-up units. Battery run times of these devices are variable and have not been reported. Different conditions of use can extend battery life in the event of electrical failure. This study was designed to examine the run time of a fully charged battery under various conditions of pump speed, pressure loads, pump boot material, multiple pump usage, and battery life. Battery life using a centrifugal pump also was examined. The results of this study show that battery life is affected by pump speed, circuit pressure, boot stiffness, and the number of pumps in service. Centrifugal pumps also show a reduced drain on battery when compared with roller pumps. These elements affect the longevity and performance of the battery. This information could be of value to the individual during power failure as these are variables that can affect the battery life during such a challenging scenario.

  8. Development and test of a plastic deep-well pump

    Science.gov (United States)

    Zhang, Q. H.; Gao, X. F.; Xu, Y.; Shi, W. D.; Lu, W. G.; Liu, W.

    2013-12-01

    To develop a plastic deep-well pump, three methods are proposed on structural and forming technique. First, the major hydraulic components are constructed by plastics, and the connection component is constructed by steel. Thus the pump structure is more concise and slim, greatly reducing its weight and easing its transportation, installation, and maintenance. Second, the impeller is designed by maximum diameter method. Using same pump casing, the stage head is greatly increased. Third, a sealing is formed by impeller front end face and steel end face, and two slots are designed on the impeller front end face, thus when the two end faces approach, a lubricating pair is formed, leading to an effective sealing. With above methods, the pump's axial length is greatly reduced, and its stage head is larger and more efficient. Especially, the pump's axial force is effectively balanced. To examine the above proposals, a prototype pump is constructed, and its testing results show that the pump efficiency exceeds the national standard by 6%, and the stage head is improved by 41%, meanwhile, its structure is more concise and ease of transportation. Development of this pump would provide useful experiences for further popularity of plastic deep-well pumps.

  9. Electronic Unit Pump Test Bench Development and Pump Properties Research

    Institute of Scientific and Technical Information of China (English)

    LIU Bo-lan; HUANG Ying; ZHANG Fu-jun; ZHAO Chang-lu

    2006-01-01

    A unit pump test bench is developed on an in-line pump test platform. The bench is composed of pump adapting assembly, fuel supply subsystem, lubricating subsystem and a control unit. A crank angle domain injection control method is given out and the control accuracy can be 0.1° crank degree. The bench can test bot h mechanical unit pump and electronic unit pump. A test model-PLD12 electronic unit pump is tested. Full pump delivery map and some influence factors test is d one. Experimental results show that the injection quantity is linear with the de livery angle. The quantity change rate is 15% when fuel temperature increases 30℃. The delivery quantity per cycle increases 30mg at 28V drive voltage. T he average delivery difference for two same type pumps is 5%. Test results show that the bench can be used for unit pump verification.

  10. Modified host cells with efflux pumps

    Science.gov (United States)

    Dunlop, Mary J.; Keasling, Jay D.; Mukhopadhyay, Aindrila

    2016-08-30

    The present invention provides for a modified host cell comprising a heterologous expression of an efflux pump capable of transporting an organic molecule out of the host cell wherein the organic molecule at a sufficiently high concentration reduces the growth rate of or is lethal to the host cell.

  11. Heat driven pulse pump

    Science.gov (United States)

    Benner, Steve M (Inventor); Martins, Mario S. (Inventor)

    2000-01-01

    A heat driven pulse pump includes a chamber having an inlet port, an outlet port, two check valves, a wick, and a heater. The chamber may include a plurality of grooves inside wall of the chamber. When heated within the chamber, a liquid to be pumped vaporizes and creates pressure head that expels the liquid through the outlet port. As liquid separating means, the wick, disposed within the chamber, is to allow, when saturated with the liquid, the passage of only liquid being forced by the pressure head in the chamber, preventing the vapor from exiting from the chamber through the outlet port. A plurality of grooves along the inside surface wall of the chamber can sustain the liquid, which is amount enough to produce vapor for the pressure head in the chamber. With only two simple moving parts, two check valves, the heat driven pulse pump can effectively function over the long lifetimes without maintenance or replacement. For continuous flow of the liquid to be pumped a plurality of pumps may be connected in parallel.

  12. PCM Vulcain : a pumping revolution in the thermal recovery of heavy oil

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-01-15

    Nearly half of the world's oil reserves are made up of unconventional heavy oil that requires thermal recovery methods. Since the oil pumped to the surface is extremely hot (350 degrees C), traditional pumps such as standard progressing cavity pumps, sucker rod pumps and electrical submersible pumps are limited in terms of maximum operating temperature. For that reason, PCM developed the PCM Vulcain, a revolutionary all-metal pump that is capable of extracting heavy oil and aggressive fluids during thermal recovery. The applications include artificial lifting in SAGD processes and artificial lifting in cyclic steam stimulation processes. The pump withstands the extreme downhole temperatures of thermal oil recovery and can pump extremely hot and extremely viscous fluids. PCM Vulcain provides all the advantages and flexibility of progressing cavity pump technology at extreme temperatures. The rotary action of PCM Vulcain outperforms beam pumps in overall system efficiency and it is less fragile than electric submersible pumps. PCM Vulcain provides extremely low submergence production capability and can operate at low downhole pressures and higher viscosities. PCM Vulcain also has lower capital expenditure than comparable submersible and rod pumps. In addition, it offers lower workover costs and reduced installation and operational complexity. The pump's seals reduce the risk of on-site leakage, thereby reducing environmental impact. PCM Vulcain has field-proven performance in some of the world's major unconventional oilfields, including the Athabasca oil sands in northern Alberta. 1 fig.

  13. Membrane pumping technology for helium and hydrogen isotope separation in the fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Pistunovich, V.I. [Kurchatov Inst., Moscow (Russian Federation). NFI RRC; Pigarov, A.Yu. [Kurchatov Inst., Moscow (Russian Federation). NFI RRC; Busnyuk, A.O. [Bonch-Bruyevich University, St. Petersburg (Russian Federation); Livshits, A.I. [Bonch-Bruyevich University, St. Petersburg (Russian Federation); Notkin, M.E. [Bonch-Bruyevich University, St. Petersburg (Russian Federation); Samartsev, A.A. [Bonch-Bruyevich University, St. Petersburg (Russian Federation); Borisenko, K.L. [Efremov Institute, St. Petersburg (Russian Federation); Darmogray, V.V. [Efremov Institute, St. Petersburg (Russian Federation); Ershov, B.D. [Efremov Institute, St. Petersburg (Russian Federation); Filippova, L.V. [Efremov Institute, St. Petersburg (Russian Federation); Mudugin, B.G. [Efremov Institute, St. Petersburg (Russian Federation); Odintsov, V.N. [Efremov Institute, St. Petersburg (Russian Federation); Saksagansky, G.L. [Efremov Institute, St. Petersburg (Russian Federation); Serebrennikov, D.V. [Efremov Institute, St. Petersburg (Russian Federation)

    1995-03-01

    A gas pumping system for ITER, improved by implementation of superpermeable membranes for selective hydrogen isotope exhaust, is considered. A study of the pumping capability of a niobium membrane for a hydrogen-helium mixture has been performed.Monte Carlo simulations of gas behaviour for the experimental facility and fusion reactor have been done.The scheme of the ITER pumping system with the membranes and membrane pumping technology was considered. The conceptual study the membrane pump for the ITER was done. This work gives good prospects for the membrane pumping use in ITER to reduce the total inventory of tritium necessary for reactor operation. (orig.).

  14. Comparison of peristaltic and Venturi pumps in bimanual microincisional cataract surgery.

    Science.gov (United States)

    Karaguzel, Hande; Karalezli, Aylin; Aslan, Bekir Sitki

    2009-12-01

    Comparison of peristaltic and Venturi pumps in bimanual microincision phacoemulsification on the success of the cataract surgery by using sleeveless phaco tip. Bimanual microincision phacoemulsification was done in 49 eyes using a 1.4-mm temporal clear corneal incision. A peristaltic pump was used in 23 eyes, and a Venturi pump was used in 26 eyes for phacoemulsification. Intraoperative complications, anterior chamber stability, and mean duration of surgery were recorded. Duration of surgery was shorter in the Venturi pump group. Anterior chamber stability could not be established in 17 eyes in the peristaltic pump group; it was established in all eyes in the Venturi pump group. Corneal burns were observed in two eyes in the peristaltic pump group and no eyes in the Venturi pump group. Use of a Venturi pump system and a vented gas-forced infusion system can significantly shorten surgery time and reduce risk of thermal burns.

  15. Heat pump planning handbook

    CERN Document Server

    Bonin, Jürgen

    2015-01-01

    The Heat Pump Planning Handbook contains practical information and guidance on the design, planning and selection of heat pump systems, allowing engineers, designers, architects and construction specialists to compare a number of different systems and options. Including detailed descriptions of components and their functions and reflecting the current state of technology this guide contains sample tasks and solutions as well as new model calculations and planning evaluations. Also economic factors and alternative energy sources are covered, which are essential at a time of rising heat costs. T

  16. Sorption product heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Antonini, G.; Francois, O.; Gendarme, J.P.; Guilleminot, J.J.; Meunier, F.

    1988-07-15

    A continuous operating, and thus with enhanced performance, heat pump is presented. In this heat pump, the heat transfer between the hot source and the output system or network is realized through a solid adsorbent-refrigerant couple having endothermal desorption properties and exothermal adsorption or absorption properties. The sorption products are carried in a closed cycle movement between the two parts of the reactor. Each side of the reactor is assuming always the same function and the thermal inertia have to be overcome only when starting the reactor.

  17. Regenerative adsorbent heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  18. Geothermal Heat Pump Performance

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, Tonya L.; Lienau, Paul J.

    1995-01-01

    Geothermal heat pump systems are a promising new energy technology that has shown rapid increase in usage over the past ten years in the United States. These systems offer substantial benefits to customers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data was available mainly from electric utilities on heat pump performance, energy savings and demand reduction for residential, school, and commercial building applications. Information was developed on the status of electric utility marketing programs, barriers to market penetration, incentive programs, and benefits.

  19. Geothermal heat pump performance

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, Tonya L.; Lienau, Paul J.

    1995-01-01

    Geothermal heat pump systems are a promising new energy technology that has shown rapid increase in usage over the past ten years in the United States. These systems offer substantial benefits to customers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data was available mainly from electric utilities on heat pump performance, energy savings and demand reduction for residential, school, and commercial building applications. Information was developed on the status of electric utility marketing programs, barriers to market penetration, incentive programs, and benefits.

  20. Molecular heat pump.

    Science.gov (United States)

    Segal, Dvira; Nitzan, Abraham

    2006-02-01

    We propose a molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation wave forms, thus making it possible to optimize the device performance.

  1. Compact High Efficiency Adsorption Heat Pump

    OpenAIRE

    TeGrotenhuis, Ward E; Humble, Paul H; Sweeney, Josh B

    2012-01-01

    An innovative adsorption cycle heat pump technology is presented that is compact and capable of achieving high energy efficiency for integrated space heating, air conditioning, and water heating. High energy efficiency is accomplished by effectively recuperating heat within the system to minimize energy consumption. This substantially reduces the thermodynamic losses that occur when the sorbent beds are thermally cycled without effective heat recuperation. Furthermore, equipment cost is reduc...

  2. Solar assisted heat pumps: a possible wave of the future

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, F.O.

    1976-12-01

    With the higher costs of electric power and the widespread interest to use solar energy to reduce the national dependence on fossil fuels, heat pumps are examined to determine their suitability for use with solar energy systems.

  3. Solar assisted heat pumps: A possible wave of the future

    Science.gov (United States)

    Smetana, F. O.

    1976-01-01

    With the higher costs of electric power and the widespread interest to use solar energy to reduce the national dependence on fossil fuels, heat pumps are examined to determine their suitability for use with solar energy systems.

  4. A mathematical model of the distillation units with heat pump

    Directory of Open Access Journals (Sweden)

    A. V. Zhuchkov

    2013-01-01

    Full Text Available Efficient hardware design of the rectification process and reduce energy costs for their implementation is an urgent task. The mathematical description of the alcohol distillation process using a heat pump was obtained in this study.

  5. Elevator was Worked by Water and Water Pump

    National Research Council Canada - National Science Library

    Mohammad Mehdi Masoumi; Soheila Naderinezhad

    2012-01-01

    In this research, it has been attempted to show that some elevators work with water and their energy consumption could be reduced because of water pump usage instead of powerful gear motor of the present day elevators...

  6. East Mesa geothermal pump test facility (EMPTF). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Olander, R.G.; Roberts, G.K.

    1984-11-28

    The design, fabrication and installation of a geothermal pump test facility (EMPFT) at the DOE geothermal site at East Mesa, California which is capable of testing 70 to 750 horsepower downwell pumps in a controlled geothermal environment were completed. The facility consists of a skid-mounted brine control module, a 160 foot below test well section, a hydraulic turbine for power recovery, a gantry-mounted hoist for pump handling and a 3-phase, 480 VAC, 1200 amp power supply to handle pump electric requirements. Geothermal brine is supplied to the EMPTF from one of the facility wells at East Mesa. The EMPTF is designed with a great amount of flexibility. The 20-inch diameter test well can accommodate a wide variety of pumps. The controls are interactive and can be adjusted to obtain a full complement of pump operation data, or set to maintain constant conditions to allow long-term testing with a minimum of operator support. The hydraulic turbine allows the EMPTF user to recover approximately 46% of the input pump power to help defray the operating cost of the unit. The hoist is provided for material handling and pump servicing and reduces the equipment that the user must supply for pump installation, inspection and removal.

  7. East Mesa geothermal pump test facility (EMPTF). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Olander, R.G.; Roberts, G.K.

    1984-11-28

    Barber-Nichols has completed the design, fabrication and installation of a geothermal pump test facility at the DOE geothermal site at East Mesa, California which is capable of testing 70 to 750 horsepower downwell pumps in a controlled geothermal environment. The facility consists of a skid-mounted brine control module, a 160 foot below ground test well section, a hydraulic turbine for power recovery, a gantry-mounted hoist for pump handling and a 3-phase, 480 VAC, 1200 amp power supply to handle pump electric requirements. Geothermal brine is supplied to the EMPTF from one of the facility wells at East Mesa. The EMPTF is designed with a great amount of flexibility to attract the largest number of potential users. The 20-inch diameter test well can accommodate a wide variety of pumps. The controls are interactive and can be adjusted to obtain a full complement of pump operation data, or set to maintain constant conditions to allow long-term testing with a minimum of operator support. The hydraulic turbine allows the EMPTF user to recover approximately 46% of the input pump power to help defray the operating cost of the unit. The hoist is provided for material handling and pump servicing and reduces the equipment that the user must supply for pump installation, inspection and removal.

  8. Influence Analysis of Wuhan Energy-economizing and Pollution reducing Actions by Adopting Ground Source Heat Pump System%地源热泵对武汉节能减排的影响分析

    Institute of Scientific and Technical Information of China (English)

    王宇波; 周戎

    2009-01-01

    Ground source heat pump (GSHP), a new technology to realize the temperature control by using superficial geothermal energy, plays an important role in the conservation of energy resource as well as environment protection. The unique geographical and climatic conditions enlarge the field to which GSHPs can be introduced. Adding to the possibility of promoting newly-born system on a large scale is the successful operation of demonstration project Wuhan government might as well promote and develop the ground source heat pump system in the process of contributing a resource-saving and environment friendly society, by way of overall planning and special supporting.%地源热泵是利用浅表地热能实现空气温度调节的新技术,具有节能、环保的明显效应.武汉独特的地理气候条件和丰富的地下水资源使得地源热泵系统具有广阔的发展空间,示范工程的成功运行为大规模推广地源热泵技术提供了可靠依据.在武汉建设"两型社会"北进程中,应采取总体规划、集中管理、专项扶持和鼓励创新等措施,以充分发挥地源热泵技术对武汉"节能减排"的重要作用.

  9. Pressurized Vessel Slurry Pumping

    Energy Technology Data Exchange (ETDEWEB)

    Pound, C.R.

    2001-09-17

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air.

  10. Microfluidic "blinking" bubble pump

    NARCIS (Netherlands)

    Yin, Zhizhong; Prosperetti, Andrea

    2005-01-01

    The paper reports data obtained on a simple micropump, suitable for electrolytes, based on the periodic growth and collapse of a single vapor bubble in a microchannel. With a channel diameter of the order of 100 µm, pumping rates of several tens of µl/min and pressure differences of several kPa are

  11. Cold Climate Heat Pump

    Science.gov (United States)

    2013-08-01

    12. Data set 7 – energy consumption of heat pump and furnace ................................ 22 Figure 13. Experimentally adjusted TRNSYS model...minute SCF standard cubic feet SEER seasonal energy efficiency ratio SH superheated TMY Typical Meteorological Year TRNSYS Transient Systems...Simulation Program ( TRNSYS ), to generate an experimentally adjusted, simulation heating seasonal performance. 6.4.1 Simulation Results The TRNSYS model

  12. The Osmotic Pump

    Science.gov (United States)

    Levenspiel, Octave; de Nevers, Noel

    1974-01-01

    Describes the principle involved in an osmotic pump used to extract fresh water from the oceans and in an osmotic power plant used to generate electricity. Although shown to be thermodynamically feasible, the osmotic principle is not likely to be used commerically for these purposes in the near future. (JR)

  13. Optimization of compound gear pump

    Institute of Scientific and Technical Information of China (English)

    栾振辉

    2002-01-01

    This paper introduces the performances of compound gear pump. Based on the target of having the smallest mass per unit volume, the paper established a mathematical model of optimization, and obtained the results of optimization of the pump.

  14. RSES heat pump technician certification

    Energy Technology Data Exchange (ETDEWEB)

    Zeiner, J.

    1996-06-01

    In 1987 the National Heat Pump certification test was developed by the Refrigeration Service Engineers Society (RSES), and in 1994, the program was more specifically named Heat Pump Service Technician Certification. This report describes the benefits of certification.

  15. Orbital Liquid Oxygen Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed work will develop a pump, which is based on two novel and unique design features. The first feature is a lobed pumping mechanism which operates with...

  16. VIRTUAL FUEL-PUMP DESIGN

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Some concepts of virtual product are discussed. The key technologies of virtual fuel-pump development are in detail analysed, which include virtual fuel-pump product modeling, intelligent simulation, distributed design environment, and virtual assembly. The virtual fuel-pump development prototype system considers requirement analysis, concept design, injection preferment analysis, detailed design, and assembly analysis.

  17. Small Scroll Pump for Cryogenic Liquids Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a compact, reliable, light weight, electrically driven pump capable of pumping cryogenic liquids, based on scroll pump technology. This pump will...

  18. Improving pumping system efficiency at coal plants

    Energy Technology Data Exchange (ETDEWEB)

    Livoti, W.C.; McCandless, S.; Poltorak, R. [Baldor Electric Co. (United States)

    2009-03-15

    The industry must employ ultramodern technologies when building or upgrading power plant pumping systems thereby using fuels more efficiently. The article discusses the uses and efficiencies of positive displacement pumps, centrifugal pumps and multiple screw pumps. 1 ref., 4 figs.

  19. Pumping characteristics of roots blower pumps for light element gases

    Energy Technology Data Exchange (ETDEWEB)

    Hiroki, Seiji; Abe, Tetsuya; Tanzawa, Sadamitsu; Nakamura, Jun-ichi; Ohbayashi, Tetsuro [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2002-07-01

    The pumping speed and compression ratio of the two-stage roots blower pumping system were measured for light element gases (H{sub 2}, D{sub 2} and He) and for N{sub 2}, in order to assess validity of the ITER torus roughing system as an ITER R and D task (T234). The pumping system of an Edwards EH1200 (nominal pumping speed of 1200 m{sup 3}/s), two EH250s (ibid. 250 m{sup 3}/s) and a backing pump (ibid. 100 m{sup 3}/s) in series connection was tested under PNEUROP standards. The maximum pumping speeds of the two-stage system for D{sub 2} and N{sub 2} were 1200 and 1300 m{sup 3}/h, respectively at 60 Hz, which satisfied the nominal pumping speed. These experimental data support the design validity of the ITER torus roughing system. (author)

  20. Graphical user interface simplifies infusion pump programming and enhances the ability to detect pump-related faults.

    Science.gov (United States)

    Syroid, Noah; Liu, David; Albert, Robert; Agutter, James; Egan, Talmage D; Pace, Nathan L; Johnson, Ken B; Dowdle, Michael R; Pulsipher, Daniel; Westenskow, Dwayne R

    2012-11-01

    Drug administration errors are frequent and are often associated with the misuse of IV infusion pumps. One source of these errors may be the infusion pump's user interface. We used failure modes-and-effects analyses to identify programming errors and to guide the design of a new syringe pump user interface. We designed the new user interface to clearly show the pump's operating state simultaneously in more than 1 monitoring location. We evaluated anesthesia residents in laboratory and simulated environments on programming accuracy and error detection between the new user interface and the user interface of a commercially available infusion pump. With the new user interface, we observed the number of programming errors reduced by 81%, the number of keystrokes per task reduced from 9.2 ± 5.0 to 7.5 ± 5.5 (mean ± SD), the time required per task reduced from 18.1 ± 14.1 seconds to 10.9 ± 9.5 seconds and significantly less perceived workload. Residents detected 38 of 70 (54%) of the events with the new user interface and 37 of 70 (53%) with the existing user interface, despite no experience with the new user interface and extensive experience with the existing interface. The number of programming errors and workload were reduced partly because it took less time and fewer keystrokes to program the pump when using the new user interface. Despite minimal training, residents quickly identified preexisting infusion pump problems with the new user interface. Intuitive and easy-to-program infusion pump interfaces may reduce drug administration errors and infusion pump-related adverse events.

  1. SHINE Vacuum Pump Test Verification

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Gregg A; Peters, Brent

    2013-09-30

    Normetex pumps used world-wide for tritium service are no longer available. DOE and other researchers worldwide have spent significant funds characterizing this pump. Identification of alternate pumps is required for performance and compatibility with tritium gas. Many of the pumps that could be used to meet the functional performance requirements (e.g. pressure and flow conditions) of the Normetex pump have features that include the use of polymers or oils and greases that are not directly compatible with tritium service. This study assembles a test system to determine the flow characteristics for candidate alternate pumps. These tests are critical to the movement of tritium through the SHINE Tritium Purification System (TPS). The purpose of the pump testing is two-fold: (1) obtain baseline vacuum pump characteristics for an alternate (i.e. ''Normetex replacement'') pump intended for use in tritium service; and (2) verify that low pressure hydrogen gas can be transported over distances up to 300 feet by the candidate pumps. Flow rates and nominal system pressures have been identified for the SHINE Mo-99 production process Tritium Purification System (TPS). To minimize the line sizes for the transfer of low pressure tritium from the Neutron Driver Accelerator System (NDAS) to the primary processing systems in the TPS, a ''booster'' pump has been located near the accelerator in the design. A series of pump tests were performed at various configurations using hydrogen gas (no tritium) to ensure that this concept is practical and maintains adequate flow rates and required pressures. This report summarizes the results of the tests that have been performed using various pump configurations. The current design of the Tritium Purification System requires the ''booster'' pump to discharge to or to be backed by another vacuum pump. Since Normetex pumps are no longer manufactured, a commercially available Edwards

  2. 14 CFR 23.991 - Fuel pumps.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel pumps. 23.991 Section 23.991... § 23.991 Fuel pumps. (a) Main pumps. For main pumps, the following apply: (1) For reciprocating engine installations having fuel pumps to supply fuel to the engine, at least one pump for each engine must be...

  3. Pocket pumped image analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kotov, I.V., E-mail: kotov@bnl.gov [Brookhaven National Laboratory, Upton, NY 11973 (United States); O' Connor, P. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Murray, N. [Centre for Electronic Imaging, Open University, Milton Keynes, MK7 6AA (United Kingdom)

    2015-07-01

    The pocket pumping technique is used to detect small electron trap sites. These traps, if present, degrade CCD charge transfer efficiency. To reveal traps in the active area, a CCD is illuminated with a flat field and, before image is read out, accumulated charges are moved back and forth number of times in parallel direction. As charges are moved over a trap, an electron is removed from the original pocket and re-emitted in the following pocket. As process repeats one pocket gets depleted and the neighboring pocket gets excess of charges. As a result a “dipole” signal appears on the otherwise flat background level. The amplitude of the dipole signal depends on the trap pumping efficiency. This paper is focused on trap identification technique and particularly on new methods developed for this purpose. The sensor with bad segments was deliberately chosen for algorithms development and to demonstrate sensitivity and power of new methods in uncovering sensor defects.

  4. Wavy tube heat pumping

    Energy Technology Data Exchange (ETDEWEB)

    Haldeman, C. W.

    1985-12-03

    A PVC conduit about 4'' in diameter and a little more than 40 feet long is adapted for being seated in a hole in the earth and surrounds a coaxial copper tube along its length that carries Freon between a heat pump and a distributor at the bottom. A number of wavy conducting tubes located between the central conducting tube and the wall of the conduit interconnect the distributor with a Freon distributor at the top arranged for connection to the heat pump. The wavy conducting tubing is made by passing straight soft copper tubing between a pair of like opposed meshing gears each having four convex points in space quadrature separated by four convex recesses with the radius of curvature of each point slightly less than that of each concave recess.

  5. Advanced heat pump cycle

    Energy Technology Data Exchange (ETDEWEB)

    Groll, E.A.; Radermacher, R.

    1993-07-01

    The desorption and absorption process of a vapor compression heat pump with a solution circuit (VCHSC) proceeds at gliding temperature intervals, which can be adjusted over a wide range. In case that the gliding temperature intervals in the desorber and the absorber overlap, a modification of the VCHSC employing a desorber/absorber heat exchange (DAHX) can be introduced, which results in an extreme reduction of the pressure ratio. Although the DAHX-cycle has features of a two-stage cycle, it still requires only one solution pump, one separator and one compressor. Such a cycle for the working pair ammonia/water is built in the Energy Laboratory of the Center for Environmental Energy Engineering at the University of Maryland. The experimental results obtained with the research plant are discussed and compared to those calculated with a simulation program. The possible temperature lift between heat source and heat sink depending on the achievable COP are presented.

  6. Inertial microfluidic pump

    Science.gov (United States)

    Kornilovitch, Pavel; Govyadinov, Alexander; Markel, David; Torniainen, Erik

    2015-11-01

    The inertial pump is powered by a microheater positioned near one end of a fluidic microchannel. As the microheater explosively boils the surrounding fluid, a vapor bubble expands and then collapses asymmetrically, resulting in net flow. Such devices become an effective means of transporting fluids at microscale. They have no moving parts and can be manufactured in large numbers using standard batch fabrication processes. In this presentation, physical principles behind pump operation are described, in particular the role of reservoirs in dissipating mechanical momentum and the expansion-collapse asymmetry. An effective one-dimensional dynamic model is formulated and solved. The model is compared with full three-dimensional CFD simulations and available experimental data. Potential applications of inertial micropumps are described.

  7. Technology assessment heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, R.; Purper, G. (Battelle-Institut e.V., Frankfurt am Main (Germany, F.R.))

    Technology assessment for an increased application of heat pumps is carried out in four areas: Effects in the economics area, i.e. effects on the economic goals which are defined in the Stability Law, on the goals of the power supply policy which result from the energy programme and its projections, and on the economic structure as a whole. The whole range of social problems concerning the use of heat pumps, i.e. the questions which social groups are affected, how they react, and what consequences are they expected to have on energy conservation as an object of social policy. Consequences in the governmental and administrative sectors, i.e. effects on legislation, administration and government budgets. Effects on the ecological systems; of prime interest in this context are the utilisation of environmental energy, changes in the heat balance, and emmission of pollutants.

  8. Hydrodynamics of Pumps

    OpenAIRE

    Brennen, Christopher Earls

    1994-01-01

    The subject of this monograph is the fluid dynamics of liquid turbomachines, particularly pumps. Rather than attempt a general treatise on turbomachines, we shall focus attention on those special problems and design issues associated with the flow of liquid through a rotating machine. There are two characteristics of a liquid that lead to these special problems, and cause a significantly different set of concerns than would occur in, say, a gas turbine. These are the potential for cavitation ...

  9. Pioneering Heat Pump Project

    Energy Technology Data Exchange (ETDEWEB)

    Aschliman, Dave [Indiana Inst. of Technology, Inc., Fort Wayne, IN (United States); Lubbehusen, Mike [Indiana Inst. of Technology, Inc., Fort Wayne, IN (United States)

    2015-06-30

    This project was initiated at a time when ground coupled heat pump systems in this region were limited in size and quantity. There were economic pressures with costs for natural gas and electric utilities that had many organizations considering ground coupled heat pumps; The research has added to the understanding of how ground temperatures fluctuate seasonally and how this affects the performance and operation of the heat pumps. This was done by using a series of temperature sensors buried within the middle of one of the vertical bore fields with sensors located at various depths below grade. Trending of the data showed that there is a lag in ground temperature with respect to air temperatures in the shoulder months, however as full cooling and heating season arrives, the heat rejection and heat extraction from the ground has a significant effect on the ground temps; Additionally it is better understood that while a large community geothermal bore field serving multiple buildings does provide a convenient central plant to use, it introduces complexity of not being able to easily model and predict how each building will contribute to the loads in real time. Additional controllers and programming were added to provide more insight into this real time load profile and allow for intelligent shedding of load via a dry cooler during cool nights in lieu of rejecting to the ground loop. This serves as a means to ‘condition’ the ground loop and mitigate thermal creep of the field, as is typically observed; and It has been observed when compared to traditional heating and cooling equipment, there is still a cost premium to use ground source heat pumps that is driven mostly by the cost for vertical bore holes. Horizontal loop systems are less costly to install, but do not perform as well in this climate zone for heating mode

  10. Positive displacement rotary pump

    Science.gov (United States)

    Moody, Paul E.

    1994-04-01

    An eccentric drive rotates inside a ring that is hinged to a plate and an elastomeric curtain is wrapped around the ring and across an articulated plate. The curtain moves along a cylindrical wall inside the pump cavity to move fluid from an inlet to an outlet end of the chamber. Two or more chambers can be coupled in series or in parallel with one another.

  11. Nonazeotropic Heat Pump

    Science.gov (United States)

    Ealker, David H.; Deming, Glenn

    1991-01-01

    Heat pump collects heat from water circulating in heat-rejection loop, raises temperature of collected heat, and transfers collected heat to water in separate pipe. Includes sealed motor/compressor with cooling coils, evaporator, and condenser, all mounted in outer housing. Gradients of temperature in evaporator and condenser increase heat-transfer efficiency of vapor-compression cycle. Intended to recover relatively-low-temperature waste heat and use it to make hot water.

  12. Nonazeotropic Heat Pump

    Science.gov (United States)

    Ealker, David H.; Deming, Glenn

    1991-01-01

    Heat pump collects heat from water circulating in heat-rejection loop, raises temperature of collected heat, and transfers collected heat to water in separate pipe. Includes sealed motor/compressor with cooling coils, evaporator, and condenser, all mounted in outer housing. Gradients of temperature in evaporator and condenser increase heat-transfer efficiency of vapor-compression cycle. Intended to recover relatively-low-temperature waste heat and use it to make hot water.

  13. Introduction to Pump Rotordynamics

    Science.gov (United States)

    2006-11-01

    RTO-EN-AVT-143 9 - 1 Introduction to Pump Rotordynamics Luis San Andrés Mast-Childs Tribology Professor Turbomachinery Laboratory Texas A... rotordynamics of turbomachinery, excessive vibration and instability. The acceptable performance of a turbomachine depends on the adequate design and operation...on rotordynamics . The basic equations for the modeling of linear rotor-bearing systems are given along with an example for the rotordynamics of a

  14. On-Pump Versus Off-Pump Coronary Artery Bypass Surgery in Elderly Patients

    DEFF Research Database (Denmark)

    Holme, Susanne Juel; Houlind, Kim; Kjeldsen, Bo Juul;

    2012-01-01

    Conventional coronary artery bypass grafting performed with the use of cardiopulmonary bypass is a well-validated treatment for patients with ischemic heart disease. Off-pump coronary artery bypass grafting (OPCAB) has been suggested to reduce the number of perioperative complications, especially...... in elderly patients....

  15. Electrocentrifugal pumping; Bombeo electrocentrifugo

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Perez, Guillermo; Medellin Otero, Hector [Instituto Mexicano del Peroleo (Mexico)

    1996-07-01

    The exploitation of isolated oil deposits, in losing their own energy, enter a phase of secondary recovery. One of the technologies of new development in Mexico is the one of electrocentrifugal pumping , which consists of introducing the motor-pump as an integral part of the production pipe down to the well bottom and pumping directly up to central complexes, from where it is sent inland. In the present paper is intended to explain what this type of secondary recovery consists of. [Spanish] La explotacion de yacimientos aislados de petroleo, al perder su energia propia, entran en una fase de recuperacion secundaria. Una de las tecnologias de nuevo desarrollo en Mexico es la de bombeo electrocentrifugo, la cual consiste en introducir la motobomba como parte integral de la tuberia de produccion hasta el fondo del pozo y bombearlo directamente hasta los complejos centrales, de donde se envia a tierra. En el presente trabajo se pretende explicar en que consiste este tipo de recuperacion secundaria.

  16. Stirling Engine Heat Pump

    Science.gov (United States)

    Kagawa, Noboru

    Recent advances in the feasibility studies related to the Stirling engines and Stirling engine heat pumps which have been considered attractive due to their promising role in helping to solve the global environmental and energy problems,are reviewed. This article begins to describe the brief history of the Stirling engines and theoretical thermodynamic analysis of the Stirling cycle in order to understand several advantages on the Stirling engine. Furthermore,they could throw light on our question why the dream engines had not been promoted to practical applications during two hundred years. The present review shows that the Stirling engines with several unique advantages including 30 to 40% thermal efficiency and preferable exhaust characteristics,had been designed and constructed by recent tackling for the development of the advanced automobile and other applications using them. Based on the current state of art,it is being provided to push the Stirling engines combined with heat pumps based on the reversed Rankine cycle to the market. At present,however, many problems, especially for the durability, cost, and delicate engine parts must be enforced to solve. In addition,there are some possibilities which can increase the attractiveness of the Stirling engines and heat pumps. The review closes with suggestions for further research.

  17. A Magnetically Coupled Cryogenic Pump

    Science.gov (United States)

    Hatfield, Walter; Jumper, Kevin

    2011-01-01

    Historically, cryogenic pumps used for propellant loading at Kennedy Space Center (KSC) and other NASA Centers have a bellows mechanical seal and oil bath ball bearings, both of which can be problematic and require high maintenance. Because of the extremely low temperatures, the mechanical seals are made of special materials and design, have wearing surfaces, are subject to improper installation, and commonly are a potential leak path. The ball bearings are non-precision bearings [ABEC-1 (Annular Bearing Engineering Council)] and are lubricated using LOX compatible oil. This oil is compatible with the propellant to prevent explosions, but does not have good lubricating properties. Due to the poor lubricity, it has been a goal of the KSC cryogenics community for the last 15 years to develop a magnetically coupled pump, which would eliminate these two potential issues. A number of projects have been attempted, but none of the pumps was a success. An off-the-shelf magnetically coupled pump (typically used with corrosive fluids) was procured that has been used for hypergolic service at KSC. The KSC Cryogenics Test Lab (CTL) operated the pump in cryogenic LN2 as received to determine a baseline for modifications required. The pump bushing, bearings, and thrust rings failed, and the pump would not flow liquid (this is a typical failure mode that was experienced in the previous attempts). Using the knowledge gained over the years designing and building cryogenic pumps, the CTL determined alternative materials that would be suitable for use under the pump design conditions. The CTL procured alternative materials for the bearings (bronze, aluminum bronze, and glass filled PTFE) and machined new bearing bushings, sleeves, and thrust rings. The designed clearances among the bushings, sleeves, thrust rings, case, and case cover were altered once again using experience gained from previous cryogenic pump rebuilds and designs. The alternative material parts were assembled into

  18. Enhanced efficiency of AlGaInP disk laser by in-well pumping.

    Science.gov (United States)

    Mateo, C M N; Brauch, U; Schwarzbäck, T; Kahle, H; Jetter, M; Abdou Ahmed, M; Michler, P; Graf, T

    2015-02-09

    The performance of a 665-nm GaInP disk laser operated continuous-wave at 15°C both in-well-pumped at 640 nm and barrier pumped at 532 nm is reported. The efficiency with respect to the absorbed power was enhanced by 3.5 times when using a 640-nm pump instead of a 532-nm pump. In-well pumping which is based on the absorption of the pump photons within the quantum-well heterostructures of the gain region instead of short-wavelength absorption in the barrier and spacer regions reduces the quantum defect between pump and laser photon and hence the heat generation. A slope efficiency of 60% with respect to the absorbed pump power was obtained by in-well pumping at 15°C. Continuous-wave laser operation was further demonstrated at heat sink temperatures of up to 55°C. Both the measurement of photoluminescence and COMSOL simulation show that the overall heat load in the in-well pumped laser is smaller than in the barrier-pumped laser. These results demonstrate the potential of optical in-well pumping for the operation of red AlGaInP disk lasers if combined with means for efficient pump-light absorption.

  19. Engineering microbial biofuel tolerance and export using efflux pumps.

    Science.gov (United States)

    Dunlop, Mary J; Dossani, Zain Y; Szmidt, Heather L; Chu, Hou Cheng; Lee, Taek Soon; Keasling, Jay D; Hadi, Masood Z; Mukhopadhyay, Aindrila

    2011-05-10

    Many compounds being considered as candidates for advanced biofuels are toxic to microorganisms. This introduces an undesirable trade-off when engineering metabolic pathways for biofuel production because the engineered microbes must balance production against survival. Cellular export systems, such as efflux pumps, provide a direct mechanism for reducing biofuel toxicity. To identify novel biofuel pumps, we used bioinformatics to generate a list of all efflux pumps from sequenced bacterial genomes and prioritized a subset of targets for cloning. The resulting library of 43 pumps was heterologously expressed in Escherichia coli, where we tested it against seven representative biofuels. By using a competitive growth assay, we efficiently distinguished pumps that improved survival. For two of the fuels (n-butanol and isopentanol), none of the pumps improved tolerance. For all other fuels, we identified pumps that restored growth in the presence of biofuel. We then tested a beneficial pump directly in a production strain and demonstrated that it improved biofuel yields. Our findings introduce new tools for engineering production strains and utilize the increasingly large database of sequenced genomes.

  20. Kinematic modeling, analysis and test on a quiet spherical pump

    Science.gov (United States)

    Guan, Dong; Wu, Jiu Hui; Jing, Li; Hilton, Harry H.; Lu, Kuan

    2016-11-01

    In this paper, design and modeling of a novel spherical pump are undertaken. Both sound and vibration properties of the pump are studied experimentally. The working mechanism of the pump is analyzed firstly, and then structural design and kinematic theory are modeled by using two different coordinate systems. Nonlinear kinematic constraint equations are developed using a generalized computational method for spatial kinematic analysis. These equations are solved to yield the displacement, angular velocity and acceleration properties of motion parts with different structural parameters. Sound and vibration characteristics of the spherical pump and traditional solenoid pumps are studied experimentally at different rotating speeds of 1000, 1500, 2000, 2500 and 3000 rev/min. Results indicate that sound pressure levels of the proposed spherical are reduced to 40.7 dB(A), which are 11.1 dB(A) lower than the traditional solenoid pump's 51.8 dB(A) at the rated operating conditions. The sound spectra are analyzed in detail in order to investigate the causes, which are structural pattern and working mechanisms. The proposed spherical pump has many advantages and can be utilized as a substitute for other pumps in some special fields, such as hospital facilities and household appliances.

  1. Engineering microbial biofuel tolerance and export using efflux pumps

    Science.gov (United States)

    Dunlop, Mary J; Dossani, Zain Y; Szmidt, Heather L; Chu, Hou Cheng; Lee, Taek Soon; Keasling, Jay D; Hadi, Masood Z; Mukhopadhyay, Aindrila

    2011-01-01

    Many compounds being considered as candidates for advanced biofuels are toxic to microorganisms. This introduces an undesirable trade-off when engineering metabolic pathways for biofuel production because the engineered microbes must balance production against survival. Cellular export systems, such as efflux pumps, provide a direct mechanism for reducing biofuel toxicity. To identify novel biofuel pumps, we used bioinformatics to generate a list of all efflux pumps from sequenced bacterial genomes and prioritized a subset of targets for cloning. The resulting library of 43 pumps was heterologously expressed in Escherichia coli, where we tested it against seven representative biofuels. By using a competitive growth assay, we efficiently distinguished pumps that improved survival. For two of the fuels (n-butanol and isopentanol), none of the pumps improved tolerance. For all other fuels, we identified pumps that restored growth in the presence of biofuel. We then tested a beneficial pump directly in a production strain and demonstrated that it improved biofuel yields. Our findings introduce new tools for engineering production strains and utilize the increasingly large database of sequenced genomes. PMID:21556065

  2. Recent Development in Hydrogen Peroxide Pumped Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Ledebuhr, A G; Antelman, D R; Dobie, D W; Gorman, T S; Jones, M S; Kordas, J F; McMahon, D H; Ng, L C; Nielsen, D P; Ormsby, A E; Pittenger, L C; Robinson, J A; Skulina, K M; Taylor, W G; Urone, D A; Wilson, B A

    2004-03-22

    This paper describes the development of a lightweight high performance pump-fed divert and attitude control system (DACS). Increased kinetic Kill Vehicles (KV) capabilities (higher .v and acceleration capability) will especially be needed for boost phase engagements where a lower mass KV DACS enables smaller overall interceptors. To increase KV performance while reducing the total DACS dry mass (<10 kg), requires a design approach that more closely emulates those found in large launch vehicles, where pump-fed propulsion enables high propellant-mass-fraction systems. Miniaturized reciprocating pumps, on a scale compatible with KV applications, offer the potential of a lightweight DACS with both high {Delta}v and acceleration capability, while still enabling the rapid pulsing of the divert thrusters needed in the end-game fly-in. Pumped propulsion uses lightweight low-pressure propellant tanks, as the main vehicle structure and eliminates the need for high-pressure gas bottles, reducing mass and increasing the relative propellant load. Prior work used hydrazine and demonstrated a propellant mass fraction >0.8 and a vehicle propulsion dry mass of {approx}3 kg. Our current approach uses the non-toxic propellants 90% hydrogen peroxide and kerosene. This approach enables faster development at lower costs due to the ease of handling. In operational systems these non-toxic propellants can simplify the logistics for manned environments including shipboard applications. This DACS design configuration is expected to achieve sufficient mass flows to support divert thrusters in the 1200 N to 1330 N (270 lbf to 300 lbf) range. The DACS design incorporates two pairs of reciprocating differential piston pumps (oxidizer and fuel), a warm-gas drive system, compatible bi-propellant thrusters, lightweight valves, and lightweight low-pressure propellant tanks. This paper summarizes the current development status and plans.

  3. Proton pumping accompanies calcification in foraminifera

    Science.gov (United States)

    Toyofuku, Takashi; Matsuo, Miki Y.; de Nooijer, Lennart Jan; Nagai, Yukiko; Kawada, Sachiko; Fujita, Kazuhiko; Reichart, Gert-Jan; Nomaki, Hidetaka; Tsuchiya, Masashi; Sakaguchi, Hide; Kitazato, Hiroshi

    2017-01-01

    Ongoing ocean acidification is widely reported to reduce the ability of calcifying marine organisms to produce their shells and skeletons. Whereas increased dissolution due to acidification is a largely inorganic process, strong organismal control over biomineralization influences calcification and hence complicates predicting the response of marine calcifyers. Here we show that calcification is driven by rapid transformation of bicarbonate into carbonate inside the cytoplasm, achieved by active outward proton pumping. Moreover, this proton flux is maintained over a wide range of pCO2 levels. We furthermore show that a V-type H+ ATPase is responsible for the proton flux and thereby calcification. External transformation of bicarbonate into CO2 due to the proton pumping implies that biomineralization does not rely on availability of carbonate ions, but total dissolved CO2 may not reduce calcification, thereby potentially maintaining the current global marine carbonate production.

  4. Experimental analysis of the flow pattern of a pump turbine model in pump mode

    Science.gov (United States)

    Guggenberger, Mark; Senn, Florian; Jaberg, Helmut; Gehrer, Arno; Sallaberger, Manfred; Widmer, Christian

    2016-11-01

    Reversible pump turbines are the only means to store primary energy in an highly efficient way. Within a short time their operation can be switched between the different operational regimes thus enhancing the stabilization of the electric grid. These qualities in combination with the operation even at off-design conditions offer a high flexibility to the energy market. However, pump turbines pass through operational regimes where their behaviour becomes unstable. One of these effects occurs when the flowrate is decreased continuously down to a minimum. This point is the physical limitation of the pump operation and is very difficult to predict properly by numerical design without a model test. The purpose of the present study is to identify the fluid mechanical phenomena leading to the occurrence of instabilities of pump turbines in pump mode. A reduced scale model of a ANDRITZ pump turbine was installed on a 4-quadrant test rig for the experimental investigation of unstable conditions in pump mode. The performed measurements are based on the IEC60193-standard. Characteristic measurements at a single guide vane opening were carried out to get a detailed insight into the instabilities in pump mode. The interaction between runner and guide vane was analysed by Particle Image Velocimetry. Furthermore, high-speed visualizations of the suction side part load flow and the suction recirculation were performed. Like never before the flow pattern in the draft tube cone became visible with the help of a high-speed camera by intentionally caused cavitation effects which allow a qualitative view on the flow pattern in the draft tube cone. Suction recirculation is observed in form of single vortices separating from each runner blade and stretching into the draft tube against the main flow direction. To find an explanation for the flow phenomena responsible for the appearance of the unstable head curve also characteristic velocity distributions on the pressure side were combined

  5. Pumping Optimization Model for Pump and Treat Systems - 15091

    Energy Technology Data Exchange (ETDEWEB)

    Baker, S.; Ivarson, Kristine A.; Karanovic, M.; Miller, Charles W.; Tonkin, M.

    2015-01-15

    Pump and Treat systems are being utilized to remediate contaminated groundwater in the Hanford 100 Areas adjacent to the Columbia River in Eastern Washington. Design of the systems was supported by a three-dimensional (3D) fate and transport model. This model provided sophisticated simulation capabilities but requires many hours to calculate results for each simulation considered. Many simulations are required to optimize system performance, so a two-dimensional (2D) model was created to reduce run time. The 2D model was developed as a equivalent-property version of the 3D model that derives boundary conditions and aquifer properties from the 3D model. It produces predictions that are very close to the 3D model predictions, allowing it to be used for comparative remedy analyses. Any potential system modifications identified by using the 2D version are verified for use by running the 3D model to confirm performance. The 2D model was incorporated into a comprehensive analysis system (the Pumping Optimization Model, POM) to simplify analysis of multiple simulations. It allows rapid turnaround by utilizing a graphical user interface that: 1 allows operators to create hypothetical scenarios for system operation, 2 feeds the input to the 2D fate and transport model, and 3 displays the scenario results to evaluate performance improvement. All of the above is accomplished within the user interface. Complex analyses can be completed within a few hours and multiple simulations can be compared side-by-side. The POM utilizes standard office computing equipment and established groundwater modeling software.

  6. Supercritical waste oxidation pump investigation

    Energy Technology Data Exchange (ETDEWEB)

    Thurston, G.; Garcia, K.

    1993-02-01

    This report investigates the pumping techniques and pumping equipment that would be appropriate for a 5,000 gallon per day supercritical water oxidation waste disposal facility. The pumps must boost water, waste, and additives from atmospheric pressure to approximately 27.6 MPa (4,000 psia). The required flow ranges from 10 gpm to less than 0.1 gpm. For the higher flows, many commercial piston pumps are available. These pumps have packing and check-valves that will require periodic maintenance; probably at 2 to 6 month intervals. Several commercial diaphragm pumps were also discovered that could pump the higher flow rates. Diaphragm pumps have the advantage of not requiring dynamic seals. For the lower flows associated with the waste and additive materials, commercial diaphragm pumps. are available. Difficult to pump materials that are sticky, radioactive, or contain solids, could be injected with an accumulator using an inert gas as the driving mechanism. The information presented in this report serves as a spring board for trade studies and the development of equipment specifications.

  7. Tank farms pump critical characteristic and specification guide

    Energy Technology Data Exchange (ETDEWEB)

    Titzler, P.A.

    1997-01-17

    The Design Authority group for Tank Farms, in conjunction with the Construction Projects organization, have recognized that there is a need to provide consistency in the procurement and testing of pumps and to assure that known critical attributes and features are included with each pump order as well as to reduce potential confusion by pump suppliers. As a result, a panel of pump experts representing Lockheed Martin Hanford Company (LMHC), Fluor Daniel Northwest (FDNW), Numatec Hanford Corporation (NHC), SGN Eurisys Services Corporation (SESC), and ARES Corporation has been assembled to prepare a guide for pump specifications. This document contains the consensus listing of critical characteristics and procurement recommendations of the panel. It is intended to be used as a guide for future pump procurement activities. If followed, it will help reduce cleanup costs at the Hanford Site and promote prompt approval of pumping system designs and procurement specifications. Alternate criteria may be specified on a case by case basis if deviation from the requirements contained herein is merited due to special circumstances.

  8. A magnetically levitated centrifugal blood pump with a simple-structured disposable pump head.

    Science.gov (United States)

    Hijikata, Wataru; Shinshi, Tadahiko; Asama, Junichi; Li, Lichuan; Hoshi, Hideo; Takatani, Setsuo; Shimokohbe, Akira

    2008-07-01

    A magnetically levitated centrifugal blood pump (MedTech Dispo) has been developed for use in a disposable extracorporeal system. The design of the pump is intended to eliminate mechanical contact with the impeller, to facilitate a simple disposable mechanism, and to reduce the blood-heating effects that are caused by motors and magnetic bearings. The bearing rotor attached to the impeller is suspended by a two degrees-of-freedom controlled radial magnetic bearing stator, which is situated outside the rotor. In the space inside the ringlike rotor, a magnetic coupling disk is placed to rotate the rotor and to ensure that the pump head is thermally isolated from the motor. In this system, the rotor can exhibit high passive stiffness due to the novel design of the closed magnetic circuits. The disposable pump head, which has a priming volume of 23 mL, consists of top and bottom housings, an impeller, and a rotor with a diameter of 50 mm. The pump can provide a head pressure of more than 300 mm Hg against a flow of 5 L/min. The normalized index of hemolysis of the MedTech Dispo is 0.0025 +/- 0.0005 g/100 L at 5 L/min against 250 mm Hg. This is one-seventh of the equivalent figure for a Bio Pump BPX-80 (Medtronic, Inc., Minneapolis, MN, USA), which has a value of 0.0170 +/- 0.0096 g/100 L. These results show that the MedTech Dispo offers high pumping performance and low blood trauma.

  9. Synchronous Optical Pumping of Quantum Revival Beats for Atomic Magnetometery

    CERN Document Server

    Seltzer, S J; Romalis, M V

    2006-01-01

    We observe quantum beats with periodic revivals due to non-linear spacing of Zeeman levels in the ground state of potassium atoms and demonstrate their synchronous optical pumping by double modulation of the pumping light at the Larmor frequency and the revival frequency. We show that synchronous pumping increases the degree of spin polarization by a factor of 4. As a practical example, we explore the application of this double-modulation technique to atomic magnetometers operating in the geomagnetic field range and find that it can increase the sensitivity and reduce magnetic field orientation-dependent measurement errors endemic to alkali-metal magnetometers.

  10. Tapered diode laser pumped 946 nm Nd:YAG laser

    DEFF Research Database (Denmark)

    Cheng, Haynes Pak Hay; Jensen, Ole Bjarlin; Petersen, Paul Michael

    2009-01-01

    We successfully implemented a 946 nm Nd:YAG laser based on a 808 nm tapered diode pump laser. The tapered diode is developed at the Ferdinand-Braun-Institute fur Hochstfrequenztechnik in Germany. Figure 2 shows the experimental setup and results of each pump source coupled into a 1.5 mm crystal...... laser, we show that tapered diode laser pumping potentially increase the power of 946 nm lasers by a factor of two and reduce the threshold by a factor of three....

  11. Elevator was Worked by Water and Water Pump

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Masoumi

    2012-12-01

    Full Text Available In this research, it has been attempted to show that some elevators work with water and their energy consumption could be reduced because of water pump usage instead of powerful gear motor of the present day elevators. Power of gear motor elevators is between 3.7 to 7.5 kw and the power of water pump elevator is 1.5 kw. Water, a tank of counter weight and water pumps operate this elevator. Consequently, it can save energy especially when two or more elevators are placed adjacent to each other. The discussion of this study concentrates on the dynamic simulation and physics of this type of elevators.

  12. Ultra high vacuum pumping system and high sensitivity helium leak detector

    Science.gov (United States)

    Myneni, Ganapati Rao

    1997-01-01

    An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10.sup.-13 atm cc s.sup.-1. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces backstreaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium.

  13. Direct pumping of four levels lasing materials

    Science.gov (United States)

    Goldring, Sharone; Lavi, Raphael; Tal, Alon; Jackel, Steven M.; Lebiush, Eyal; Tzuk, Yitshak; Azoulay, Ehud

    2003-06-01

    Heat generation and laser performance were studied in Nd:YAG oscillators pumped with a Ti:Sapphire laser in two regimes: band pumping at 802nm and direct pumping at 885nm. Slope efficiencies of 52% and 57%, when pumped at 802nm and 885nm, were obtained, respectively. Heat per unit laser output was found to be 27% lower when pumped at 885nm (direct pumping regime) as compared to traditional band pumping around 808nm.

  14. Optimizing the pumping configuration for the power scaling of in-band pumped erbium doped fiber amplifiers.

    Science.gov (United States)

    Lim, Ee-Leong; Alam, Shaif-ul; Richardson, David J

    2012-06-18

    A highly efficient (~80%), high power (18.45 W) in-band, core pumped erbium/ytterbium co-doped fiber laser is demonstrated. To the best of our knowledge, this is the highest reported efficiency from an in-band pumped 1.5 µm fiber laser operating in the tens of watts regime. Using a fitted simulation model, we show that the significantly sub-quantum limit conversion efficiency of in-band pumped erbium doped fiber amplifiers observed experimentally can be explained by concentration quenching. We then numerically study and experimentally validate the optimum pumping configuration for power scaling of in-band, cladding pumped erbium doped fiber amplifiers. Our simulation results indicate that a ~77% power conversion efficiency with high output power should be possible through cladding pumping of current commercially available pure Erbium doped active fibers providing the loss experienced by the cladding guided 1535 nm pump due to the coating absorption can be reduced to an acceptable level by better coating material choice. The power conversion efficiency has the potential to exceed 90% if concentration quenching of erbium ions can be reduced via improvements in fiber design and fabrication.

  15. Proper Sizing of Circulation Pumps

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Nørgaard, Jørgen

    2007-01-01

    , but the results can be applied to Europe in general. Despite the small sample of houses involved in the test, 15 houses, some rather safe conclusions can be drawn from the results, which showed that newly developed pumps with power consumption around 5-8 W, can perform the task of circulating the water...... sufficiently to keep the houses satisfactorily warm during the heating season of the test. The old replaced pumps used 5-10 times more power. In Europe alone, a gradual replacement of the present vastly oversized pumps with such small but sufficient pumps can save the construction of 17 large power plants...... as well as their pollution during operation. Policy measures are proposed of how to ensure that in the future only such energy saving pumps are installed. Furthermore, on the basis of the historic experiences with circulation pumps some con¬clusions are drawn on how to investigate, develop and market new...

  16. Computational fluid dynamics analysis of the pediatric tiny centrifugal blood pump (TinyPump).

    Science.gov (United States)

    Kido, Kazuyuki; Hoshi, Hideo; Watanabe, Nobuo; Kataoka, Hiroyuki; Ohuchi, Katsuhiro; Asama, Junichi; Shinshi, Tadahiko; Yoshikawa, Masaharu; Takatani, Setsuo

    2006-05-01

    We have developed a tiny rotary centrifugal blood pump for the purpose of supporting circulation of children and infants. The pump is designed to provide a flow of 0.1-4.0 L/min against a head pressure of 50-120 mm Hg. The diameter of the impeller is 30 mm with six straight vanes. The impeller is supported by a hydrodynamic bearing at its center and rotated with a radial coupled magnetic driver. The bearing that supports rotation of the impeller of the tiny centrifugal blood pump is very critical to achieve durability, and clot-free and antihemolytic performance. In this study, computational fluid dynamics (CFD) analysis was performed to quantify the secondary flow through the hydrodynamic bearing at the center of the impeller and investigated the effects of bearing clearance on shear stress to optimize hemolytic performance of the pump. Two types of bearing clearance (0.1 and 0.2 mm) were studied. The wall shear stress of the 0.1-mm bearing clearance was lower than that of 0.2-mm bearing clearance at 2 L/min and 3000 rpm. This was because the axial component of the shear rate significantly decreased due to the narrower clearance even though the circumferential component of the shear rate increased. Hemolysis tests showed that the normalized index of hemolysis was reduced to 0.0076 g/100 L when the bearing clearance was reduced to 0.1 mm. It was found that the CFD prediction supported the experimental trend. The CFD is a useful tool for optimization of the hydrodynamic bearing design of the centrifugal rotary blood pump to optimize the performance of the pump in terms of mechanical effect on blood cell elements, durability of the bearing, and antithrombogenic performance.

  17. Transverse Mode Formation in Longitudinally Pumped Miniature Slab Lasers

    Institute of Scientific and Technical Information of China (English)

    XU Jian-Qiu; YE Xin; FANG Tao

    2006-01-01

    The formation of transverse modes in longitudinally pumped miniature slab lasers is investigated theoretically and experimentally. The longitudinally non-uniform gain-guiding is studied by expanding the electric field into the Hermite-Gaussian functions that satisfy boundary conditions of the resonator. Non-Gaussian transversal beam profiles in the near field are found and the beam diameter is reduced when the pump spot becomes smaller. The experimental observation agrees with the theoretical calculation.

  18. Ground coupled solar heat pumps: analysis of four options

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.W.

    1981-01-01

    Heat pump systems which utilize both solar energy and energy withdrawn from the ground are analyzed using a simplified procedure which optimizes the solar storage temperature on a monthly basis. Four ways of introducing collected solar energy to the system are optimized and compared. These include use of actively collected thermal input to the heat pump; use of collected solar energy to heat the load directly (two different ways); and use of a passive option to reduce the effective heating load.

  19. Improved reliability of residential heat pumps; Foerbaettrad driftsaekerhet hos villavaermepumpar

    Energy Technology Data Exchange (ETDEWEB)

    Haglund Stignor, Caroline; Larsson, Kristin; Jensen, Sara; Larsson, Johan; Berg, Johan; Lidbom, Peter; Rolfsman, Lennart

    2012-07-01

    Today, heat pump heating systems are common in Swedish single-family houses. Many owners are pleased with their installation, but statistics show that a certain number of heat pumps break every year, resulting in high costs for both insurance companies and owners. On behalf of Laensfoersaekringars Forskningsfond, SP Energy Technology has studied the cause of the most common failures for residential heat pumps. The objective of the study was to suggest what measures to be taken to reduce the number of failures, i.e. improving the reliability of heat pumps. The methods used were analysis of public failure statistics and sales statistics and interviews with heat pump manufacturers, installers, service representatives and assessors at Laensfoersaekringar. In addition, heat pump manuals have been examined and literature searches for various methods for durability tests have been performed. Based on the outcome from the interviews the most common failures were categorized by if they; 1. Could have been prevented by better operation and maintenance of the heat pump. 2. Caused by a poorly performed installation. 3. Could have been prevented if certain parameters had been measured, recorded and followed up. 4. Are due to poor quality of components or systems. However, the results show that many of the common failures fall into several different categories and therefore, different types of measures must be taken to improve the operational reliability of residential heat pumps. The interviews tell that failures often are caused by poor installation, neglected maintenance and surveillance, and poor quality of standard components or that components are used outside their declared operating range. The quality of the installations could be improved by increasing installers' knowledge about heat pumps and by requiring that an installation protocol shall be filled-in. It is also important that the owner of the heat pump performs the preventive maintenance recommended by the

  20. Research on synchronous gear pump

    Institute of Scientific and Technical Information of China (English)

    LUAN Zhen-hui

    2010-01-01

    Based on a comprehensive analysis of the structure and existing problems of the gear pump, provided a structure principle of a synchronous gear pump. The discussions focused on the working principle, construction features and finite element analysis of the hydraulic gear. The research indicates that the new pump has such advantages as lower noise, better distributed flow and a high work pressure, and it can be widely used in hydraulic systems.

  1. Centrifugal pumps and allied machinery

    CERN Document Server

    Anderson, HH

    1994-01-01

    This book will be of vital interest to all engineers and designers concerned with centrifugal pumps and turbines. Including statistical information derived from 20000 pumps and 700 turbines with capacities of 5gpm to 5000000gpm, this book offers the widest range and scope of information currently available. Statistical analyses suggest practical methods of increasing pump performance and provide valuable data for new design aspects.

  2. A method of applying two-pump system in automatic transmissions for energy conservation

    Directory of Open Access Journals (Sweden)

    Peng Dong

    2015-06-01

    Full Text Available In order to improve the hydraulic efficiency, modern automatic transmissions tend to apply electric oil pump in their hydraulic system. The electric oil pump can support the mechanical oil pump for cooling, lubrication, and maintaining the line pressure at low engine speeds. In addition, the start–stop function can be realized by means of the electric oil pump; thus, the fuel consumption can be further reduced. This article proposes a method of applying two-pump system (one electric oil pump and one mechanical oil pump in automatic transmissions based on the forward driving simulation. A mathematical model for calculating the transmission power loss is developed. The power loss transfers to heat which requires oil flow for cooling and lubrication. A leakage model is developed to calculate the leakage of the hydraulic system. In order to satisfy the flow requirement, a flow-based control strategy for the electric oil pump is developed. Simulation results of different driving cycles show that there is a best combination of the size of electric oil pump and the size of mechanical oil pump with respect to the optimal energy conservation. Besides, the two-pump system can also satisfy the requirement of the start–stop function. This research is extremely valuable for the forward design of a two-pump system in automatic transmissions with respect to energy conservation and start–stop function.

  3. Custom Unit Pump Design and Testing for the EVA PLSS

    Science.gov (United States)

    Schuller, Michael; Kurwitz, Cable; Goldman, Jeff; Morris, Kim; Trevino, Luis

    2009-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design and test a pre-flight prototype pump for use in the Extra-vehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump must accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting non-condensable gas without becoming air locked. The chosen pump design consists of a 28 V DC, brushless, sealless, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. Although the planned flight unit will use a sensorless motor with custom designed controller, the pre-flight prototype to be provided for this project incorporates Hall effect sensors, allowing an interface with a readily available commercial motor controller. This design approach reduced the cost of this project and gives NASA more flexibility in future PLSS laboratory testing. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES verified that the pump meets the design requirements for range of flow rates, pressure drop, power consumption, working fluid temperature, operating time, gas ingestion , and restart capability under both ambient and vacuum conditions. The pump operated between 40 and 240 lbm/hr flowrate, 35 to 100 F

  4. Lasers with nuclear pumping

    CERN Document Server

    Melnikov, S P; Sizov, A N; Miley, George H

    2015-01-01

    This book covers the history of lasers with nuclear pumping (Nuclear Pumped Lasers, NPLs). This book showcases the most important results and stages of NPL development in The Russian Federal Nuclear Center (VNIIEF) as well as other Russian and international laboratories, including laboratories in the United States. The basic science and technology behind NPLs along with potential applications are covered throughout the book. As such, this book: ·         Contains a historical overview of the extensive information developed over the past 40 years of work on NPLs ·         Covers the most important results and stages of NPL development, not just in the Russian Federal Nuclear Center, VNIIEF, but also in other laboratories in Russia, the United States , and some other scattered international laboratories ·         Systematizes the fragmented information accumulated over these years of very active research and development As the first comprehensive discussion of NPLs, students, research...

  5. The terrestrial silica pump.

    Directory of Open Access Journals (Sweden)

    Joanna C Carey

    Full Text Available Silicon (Si cycling controls atmospheric CO(2 concentrations and thus, the global climate, through three well-recognized means: chemical weathering of mineral silicates, occlusion of carbon (C to soil phytoliths, and the oceanic biological Si pump. In the latter, oceanic diatoms directly sequester 25.8 Gton C yr(-1, accounting for 43% of the total oceanic net primary production (NPP. However, another important link between C and Si cycling remains largely ignored, specifically the role of Si in terrestrial NPP. Here we show that 55% of terrestrial NPP (33 Gton C yr(-1 is due to active Si-accumulating vegetation, on par with the amount of C sequestered annually via marine diatoms. Our results suggest that similar to oceanic diatoms, the biological Si cycle of land plants also controls atmospheric CO(2 levels. In addition, we provide the first estimates of Si fixed in terrestrial vegetation by major global biome type, highlighting the ecosystems of most dynamic Si fixation. Projected global land use change will convert forests to agricultural lands, increasing the fixation of Si by land plants, and the magnitude of the terrestrial Si pump.

  6. Diode-pumped laser with improved pumping system

    Science.gov (United States)

    Chang, Jim J.

    2004-03-09

    A laser wherein pump radiation from laser diodes is delivered to a pump chamber and into the lasing medium by quasi-three-dimensional compound parabolic concentrator light channels. The light channels have reflective side walls with a curved surface and reflective end walls with a curved surface. A flow tube between the lasing medium and the light channel has a roughened surface.

  7. 33 CFR 157.126 - Pumps.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Pumps. 157.126 Section 157.126... Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.126 Pumps. (a) Crude oil must be supplied to the COW machines by COW system pumps or cargo pumps. (b) The pumps under...

  8. Design of Pumps for Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Klit, Peder; Olsen, Stefan; Bech, Thomas Nørgaard

    1999-01-01

    This paper considers the development of two pumps for water hydraulic applications. The pumps are based on two different working principles: The Vane-type pump and the Gear-type pump. Emphasis is put on the considerations that should be made to account for water as the hydraulic fluid.......KEYWORDS: water, pump, design, vane, gear....

  9. About Variable Speed Heating and Cooling Pumps

    OpenAIRE

    Cătălin Popovici; Jan Ignat

    2009-01-01

    The present work has the purpose of underlying the advantages of variable speed heating and cooling pumps use for the perspective of general and particular pumping costs and efficiency. The study approaches comparisons between constant flow pumps and variable flow pumps in different given situations and comparatively analyses the pumping costs.

  10. 46 CFR 119.520 - Bilge pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Bilge pumps. 119.520 Section 119.520 Shipping COAST... Ballast Systems § 119.520 Bilge pumps. (a) Each vessel must be provided with bilge pumps in accordance... have a portable hand bilge pump that must be: (1) Capable of pumping water, but not...

  11. 46 CFR 154.1135 - Pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pumps. 154.1135 Section 154.1135 Shipping COAST GUARD... Pumps. (a) Water to the water spray system must be supplied by: (1) A pump that is only for the use of the system; (2) A fire pump; or (3) A pump specially approved by the Commandant (CG-522)....

  12. Heat-Powered Pump for Liquid Metals

    Science.gov (United States)

    Campana, R. J.

    1986-01-01

    Proposed thermoelectromagnetic pump for liquid metal powered by waste heat; needs no battery, generator, or other external energy source. Pump turns part of heat in liquid metal into pumping energy. In combination with primary pump or on its own, thermoelectric pump circulates coolant between reactor and radiator. As long as there is decay heat to be removed, unit performs function.

  13. Heat-Powered Pump for Liquid Metals

    Science.gov (United States)

    Campana, R. J.

    1986-01-01

    Proposed thermoelectromagnetic pump for liquid metal powered by waste heat; needs no battery, generator, or other external energy source. Pump turns part of heat in liquid metal into pumping energy. In combination with primary pump or on its own, thermoelectric pump circulates coolant between reactor and radiator. As long as there is decay heat to be removed, unit performs function.

  14. Pumps in wearable ultrafiltration devices: pumps in wuf devices.

    Science.gov (United States)

    Armignacco, Paolo; Garzotto, Francesco; Bellini, Corrado; Neri, Mauro; Lorenzin, Anna; Sartori, Marco; Ronco, Claudio

    2015-01-01

    The wearable artificial kidney (WAK) is a device that is supposed to operate like a real kidney, which permits prolonged, frequent, and continuous dialysis treatments for patients with end-stage renal disease (ESRD). Its functioning is mainly related to its pumping system, as well as to its dialysate-generating and alarm/shutoff ones. A pump is defined as a device that moves fluids by mechanical action. In such a context, blood pumps pull blood from the access side of the dialysis catheter and return the blood at the same rate of flow. The main aim of this paper is to review the current literature on blood pumps, describing the way they have been functioning thus far and how they are being engineered, giving details about the most important parameters that define their quality, thus allowing the production of a radar comparative graph, and listing ideal pumps' features.

  15. Pumps used as turbines power recovery, energy efficiency, CFD analysis

    Directory of Open Access Journals (Sweden)

    Bogdanović-Jovanović Jasmina B.

    2014-01-01

    Full Text Available As the global demand for energy grows, numerous studies in the field of energy efficiency are stimulated, and one of them is certainly the use of pumps in turbine operating mode. In order to reduce time necessary to determine pump characteristic in turbine operating mode problem was studied by computational fluid dynamics approach. The paper describes various problems faced during modeling (pump and turbine mode and the approaches used to resolve the problems. Since in the majority of applications, the turbine is a pump running in reverse, many attempts have been made to predict the turbine performance from the known pump performance, but only for best efficiency point. This approach does not provide reliable data for the design of the system with maximum energy efficiency and does not allow the determination of the head for a wide range of flow rates. This paper presents an example of centrifugal norm pump operating in both (pump and turbine regime and comparison of experimentally obtained results and computational fluid dynamics simulations. [Projekat Ministarstva nauke Republike Srbije, br. TR33040: Revitalization of existing and designing new micro and mini hydropower plants (from 100 to 1000 kW in the territory of South and Southeast Serbia

  16. Affordable Hybrid Heat Pump Clothes Dryer

    Energy Technology Data Exchange (ETDEWEB)

    TeGrotenhuis, Ward E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Butterfield, Andrew [Jabil, St. Petersburg, FL (United States); Caldwell, Dustin D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Crook, Alexander [Jabil, St. Petersburg, FL (United States)

    2016-06-30

    This project was successful in demonstrating the feasibility of a step change in residential clothes dryer energy efficiency by demonstrating heat pump technology capable of 50% energy savings over conventional standard-size electric dryers with comparable drying times. A prototype system was designed from off-the-shelf components that can meet the project’s efficiency goals and are affordable. An experimental prototype system was built based on the design that reached 50% energy savings. Improvements have been identified that will reduce drying times of over 60 minutes to reach the goal of 40 minutes. Nevertheless, the prototype represents a step change in efficiency over heat pump dryers recently introduced to the U.S. market, with 30% improvement in energy efficiency at comparable drying times.

  17. Miniature reciprocating heat pumps and engines

    Science.gov (United States)

    Thiesen, Jack H. (Inventor); Willen, Gary S. (Inventor); Mohling, Robert A. (Inventor)

    2003-01-01

    The present invention discloses a miniature thermodynamic device that can be constructed using standard micro-fabrication techniques. The device can be used to provide cooling, generate power, compress gases, pump fluids and reduce pressure below ambient (operate as a vacuum pump). Embodiments of the invention relating to the production of a cooling effect and the generation of electrical power, change the thermodynamic state of the system by extracting energy from a pressurized fluid. Energy extraction is attained using an expansion process, which is as nearly isentropic as possible for the appropriately chosen fluid. An isentropic expansion occurs when a compressed gas does work to expand, and in the disclosed embodiments, the gas does work by overcoming either an electrostatic or a magnetic force.

  18. Constant-Pressure Hydraulic Pump

    Science.gov (United States)

    Galloway, C. W.

    1982-01-01

    Constant output pressure in gas-driven hydraulic pump would be assured in new design for gas-to-hydraulic power converter. With a force-multiplying ring attached to gas piston, expanding gas would apply constant force on hydraulic piston even though gas pressure drops. As a result, pressure of hydraulic fluid remains steady, and power output of the pump does not vary.

  19. [Treatment by external insulin pump].

    Science.gov (United States)

    Clavel, Sylvaine

    2010-12-01

    Since the recent recommendations by the French speaking association for research on diabetes and metabolic illnesses (Alfediam), treatment by insulin pump has found itself in competition with basal-bolus, a procedure using similar injections of insulin which has become a benchmark treatment. The latest Alfediam guidelines focus on defining ways of treating diabetics with an external insulin pump.

  20. Ion-Pumping Microbial Rhodopsins

    Directory of Open Access Journals (Sweden)

    Hideki eKandori

    2015-09-01

    Full Text Available Rhodopsins are light-sensing proteins used in optogenetics. The word rhodopsin originates from the Greek words rhodo and opsis, indicating rose and sight, respectively. Although the classical meaning of rhodopsin is the red-colored pigment in our eyes, the modern meaning of rhodopsin encompasses photoactive proteins containing a retinal chromophore in animals and microbes. Animal and microbial rhodopsins possess 11-cis and all-trans retinal, respectively, to capture light in seven transmembrane α-helices, and photoisomerizations into all-trans and 13-cis forms, respectively, initiate each function. Ion-transporting proteins can be found in microbial rhodopsins, such as light-gated channels and light-driven pumps, which are the main tools in optogenetics. Light-driven pumps, such as archaeal H+ pump bacteriorhodopsin (BR and Cl- pump halorhodopsin (HR, were discovered in the 1970s, and their mechanism has been extensively studied. On the other hand, different kinds of H+ and Cl- pumps have been found in marine bacteria, such as proteorhodopsin (PR and Fulvimarina pelagi rhodopsin (FR, respectively. In addition, a light-driven Na+ pump was found, Krokinobacter eikastus rhodopsin 2 (KR2. These light-driven ion-pumping microbial rhodopsins are classified as DTD, TSA, DTE, NTQ and NDQ rhodopsins for BR, HR, PR, FR and KR2, respectively. Recent understanding of ion-pumping microbial rhodopsins is reviewed in this paper.

  1. Thermostat-controlled coolant pump - a new concept for fuel saving

    Energy Technology Data Exchange (ETDEWEB)

    Etemad, S. [Volvo Car Components Corp., Gothenburg (Sweden); Anderson, A. [Volvo Truck Corp., Gothenburg (Sweden)

    1999-07-01

    A new coolant pump concept has been developed for better fuel economy. The flow returning from the radiator is fed coaxially into the pump. The by-pass flow is fed tangentially into the pump, generating a pre-swirl with the same direction of rotation as the coolant pump impeller. The relative velocity between the flow and the impeller decreases. This reduces the transferred momentum from the impeller to the fluid, reducing the power consumption. The flow split between the radiator and the by-pass channel is controlled by the ordinary thermostat. Results from analysis and measurements are presented. (author)

  2. Insulin pump therapy in pregnancy.

    Science.gov (United States)

    Kesavadev, Jothydev

    2016-09-01

    Control of blood glucose during pregnancy is difficult because of wide variations, ongoing hormonal changes and mood swings. The need for multiple injections, pain at the injection site, regular monitoring and skillful handling of the syringes/pen further makes insulin therapy inconvenient. Insulin pump is gaining popularity in pregnancy because it mimics the insulin delivery of a healthy human pancreas. Multiple guidelines have also recommended the use of insulin pump in pregnancy to maintain the glycaemic control. The pump can release small doses of insulin continuously (basal), or a bolus dose close to mealtime to control the spike in blood glucose after a meal and the newer devices can shut down insulin delivery before the occurrence of hypoglycaemia. Pump insulin of choice is rapid acting analogue insulin. This review underscores the role of insulin pump in pregnancy, their usage, advantages and disadvantages in the light of existing literature and clinic experience.

  3. A data pump for communication

    Science.gov (United States)

    Kang, Myong H.; Moskowitz, Ira S.

    1995-09-01

    As computer systems become more open and interconnected, the need for reliable and secure communication also increases. In this paper, we introduce a communication device, the Pump, that balances the requirements of reliability and security. The Pump provides acknowledgements (ACK's) to the message source to insure reliability. These ACK's are also used to regulate the source to prevent the Pump's buffer from becoming/staying full. This is desirable because once the buffer is filled there exists a huge covert communication channel. The Pump controls the input rate from the source by attempting to slave the input rate to the service rate through the randomized ACK back to the source. An analysis of the covert channel is also presented. The purpose of the covert channel analysis is to provide guidelines for the designer of the Pump to choose appropriate design parameters (e.g., size of buffer) dependent upon the analysis presented in this paper and system requirements.

  4. Peltier heat pumps. Peltiervaermepumpar

    Energy Technology Data Exchange (ETDEWEB)

    Torstensson, H. (Studsvik Energy, Nykoeping (SE))

    1990-06-01

    Todays Peltier devices in heat pump applications gives a low coeffificent of performance. A temperature difference of 40 deg C results in a COP-value of approx. 1.3. Peltier devices are manufactured of alloys composed of heavy elements like tellurium, selenium, bismuth and antimony. These elements thermoelectrical properties, figure of merit are decisive to the performance of the Peltier devices. An upper limit for the figure of merit, ZT, is said to be 2, which at {Delta}T=40 deg C would yield a COP of 2.0 as a maximum. Organic compounds have been investigated with regard to the electric conductivity. Thin film technique have been used for Peltier devices in micro-scale. There are no large-scale applications. The method does not give enhanced termoelectrical properties, but more rational and cheaper manufacturing. (author) (47 refs., 26 figs.).

  5. Self pumping magnetic cooling

    Science.gov (United States)

    Chaudhary, V.; Wang, Z.; Ray, A.; Sridhar, I.; Ramanujan, R. V.

    2017-01-01

    Efficient thermal management and heat recovery devices are of high technological significance for innovative energy conservation solutions. We describe a study of a self-pumping magnetic cooling device, which does not require external energy input, employing Mn-Zn ferrite nanoparticles suspended in water. The device performance depends strongly on magnetic field strength, nanoparticle content in the fluid and heat load temperature. Cooling (ΔT) by ~20 °C and ~28 °C was achieved by the application of 0.3 T magnetic field when the initial temperature of the heat load was 64 °C and 87 °C, respectively. These experiments results were in good agreement with simulations performed with COMSOL Multiphysics. Our system is a self-regulating device; as the heat load increases, the magnetization of the ferrofluid decreases; leading to an increase in the fluid velocity and consequently, faster heat transfer from the heat source to the heat sink.

  6. Electric fluid pump

    Science.gov (United States)

    Van Dam, Jeremy Daniel; Turnquist, Norman Arnold; Raminosoa, Tsarafidy; Shah, Manoj Ramprasad; Shen, Xiaochun

    2015-09-29

    An electric machine is presented. The electric machine includes a hollow rotor; and a stator disposed within the hollow rotor, the stator defining a flow channel. The hollow rotor includes a first end portion defining a fluid inlet, a second end portion defining a fluid outlet; the fluid inlet, the fluid outlet, and the flow channel of the stator being configured to allow passage of a fluid from the fluid inlet to the fluid outlet via the flow channel; and wherein the hollow rotor is characterized by a largest cross-sectional area of hollow rotor, and wherein the flow channel is characterized by a smallest cross-sectional area of the flow channel, wherein the smallest cross-sectional area of the flow channel is at least about 25% of the largest cross-sectional area of the hollow rotor. An electric fluid pump and a power generation system are also presented.

  7. Heat pumps in industry. Pt. 2: Applications

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M. [Padova Univ., Vicenza (Italy). Ist. di Ingegneria Gestionale

    1995-04-01

    A selection of applications of heat pumps in industry is described, reporting plant lay-outs and performances. The selection includes compression heat pumps at different temperatures, vapour recompression systems, absorption heat pumps and heat transformers. (author)

  8. Inactivation of Efflux Pumps Abolishes Bacterial Biofilm Formation

    DEFF Research Database (Denmark)

    Kvist, Malin; Hancock, Viktoria; Klemm, Per

    2008-01-01

    Bacterial biofilms cause numerous problems in health care and industry; notably, biofilms are associated with a large number of infections. Biofilm-dwelling bacteria are particularly resistant to antibiotics, making it hard to eradicate biofilm-associated infections. Bacteria rely on efflux pumps...... to get rid of toxic substances. We discovered that efflux pumps are highly active in bacterial biofilms, thus making efflux pumps attractive targets for antibiofilm measures. A number of efflux pump inhibitors (EPIs) are known. EPIs were shown to reduce biofilm formation, and in combination they could...... abolish biofilm formation completely. Also, EPIs were able to block the antibiotic tolerance of biofilms. The results of this feasibility study might pave the way for new treatments for biofilm-related infections and may be exploited for prevention of biofilms in general....

  9. Automatic Control of Water Pumping Stations

    Institute of Scientific and Technical Information of China (English)

    Muhannad Alrheeh; JIANG Zhengfeng

    2006-01-01

    Automatic Control of pumps is an interesting proposal to operate water pumping stations among many kinds of water pumping stations according to their functions.In this paper, our pumping station is being used for water supply system. This paper is to introduce the idea of pump controller and the important factors that must be considering when we want to design automatic control system of water pumping stations. Then the automatic control circuit with the function of all components will be introduced.

  10. Technical and Economic Working Domains of Industrial Heat Pumps: Part 2 - Ammonia-Water Hybrid Absorption-Compression Heat Pumps

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2014-01-01

    The ammonia-water hybrid absorption-compression heat pump (HACHP) is a relevant technology for industrial heat supply, especially for high sink temperatures and high temperature glides in the sink and source. This is due to the reduced vapour pressure and the non-isothermal phase change...... of the zeotropic mixture, ammonia-water. To evaluate to which extent these advantages can be translated into feasible heat pump solutions, the working domain of the HACHP is investigated based on technical and economic constraints. The HACHP working domain is compared to that of the best possible vapour...... compression heat pump with natural working fluids. This shows that the HACHP increases the temperature lifts and heat supply temperatures that are feasible to produce with a heat pump. The HACHP is shown to be capable of delivering heat supply temperatures as high as 140 XC and temperature lifts up to 60 K...

  11. Technical and economic working domains of industrial heat pumps: Part 2 - ammonia-water hybrid absorption-compression heat pumps

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2015-01-01

    The ammonia-water hybrid absorption-compression heat pump (HACHP) has been proposed as a relevant technology for industrial heat supply, especially for high sink temperatures and high temperature glides in the sink and source. This is due to the reduced vapour pressure and the non-isothermal phase...... change of the zeotropic mixture, ammonia-water. To evaluate to which extent these advantages can be translated into feasible heat pump solutions, the working domain of the HACHP is investigated based on technical and economic constraints. The HACHP working domain is compared to that of the best available...... vapour compression heat pump with natural working fluids. This shows that the HACHP increases the temperature lifts and heat supply temperatures that are feasible to produce with a heat pump. The HACHP is shown to be capable of delivering heat supply temperatures as high as 150 °C and temperature lifts...

  12. Pumping of titanium sapphire laser

    Science.gov (United States)

    Jelínková, H.; Vaněk, P.; Valach, P.; Hamal, K.; Kubelka, J.; Škoda, V.; Jelínek, M.

    1993-02-01

    Two methods of Ti:Sapphire pumping for the generation of tunable laser radiation in the visible region were studied. For coherent pumping, the radiation of the second harmonic of a Nd:YAP laser was used and a maximum output energy of E out=4.5 mJ was reached from the Ti:Sapphire laser. For noncoherent pumping, two different lengths of flashlamp pulses were used and a maximum of E out=300 mJ was obtained. Preliminary estimations of the wavelength range of tunability were made.

  13. Industrial heat pump assessment study

    Science.gov (United States)

    Chappell, R. N.; Priebe, S. J.; Wilfert, G. L.

    1989-03-01

    This report summarizes preliminary studies that assess the potential of industrial heat pumps for reduction of process heating requirements in industries receiving power from the Bonneville Power Administration (BPA). This project was initiated at the request of BPA to determine the potential of industrial heat pumps in BPA's service area. Working from known heat pump principles and from a list of BPA's industrial customers, the authors estimated the fuel savings potential for six industries. Findings indicate that the pulp and paper industry would yield the greatest fuel savings and increased electrical consumption. Assessments presented in this report represent a cooperative effort between The Idaho National Engineering Laboratory (INEL), and Battelle-Northwest Laboratories.

  14. Performance of a solar augmented heat pump

    Science.gov (United States)

    Bedinger, A. F. G.; Tomlinsin, J. J.; Reid, R. L.; Chaffin, D. J.

    Performance results from a test house equipped with a parallel solar augmented heat pump system with off-peak storage and a utility interconnection back-up, are presented. The collector array consisted of 12 air heating flat plates with a 9 l/sec flow. Thermal storage was consigned to a 260 cu ft crushed limestone pebble bed, with an 8.8 kW heat pump used to draw heat from storage during off-peak hours and a 15 kW electrical resistance heater used to charge the pebble bed. Monitoring and data recording were carried out on all energy inputs and outputs of the systems, and a modified TRNSYS program was employed to model the system performance. The data indicate that although the system offered the possibility of reducing the utility capacity, the addition of the solar system did not significantly augment the performance of the heat-pump system, at least in terms of the cost of supplementary electricity.

  15. Pump Cavitation Noise Estimation from Acceleration Signals

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Hwan; Ha, Che Woong [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    The cavitation noise can be measured directly by using pressure sensing devices. However, penetration of pipes or pump casings is inevitable to install the devices. This increases the risk of leaks. In an effort to reduce that risk, a cavitation noise estimation model based on vibration signals has been proposed. In the present study, the applicability of cavitation noise estimation methods including the previously proposed model is investigated. In order to assess the severity of cavitation, the cavitation noise estimation is necessary. In the present study, the cavitation noise is estimated by using acceleration signals measured outside of pumps and the theory of the statistical energy analysis. The applicability and limit of the cavitation noise estimation from the acceleration signals are examined by comparing the cavitation noise obtained from the pressure signal. The results suggest that the acoustic cavitation inception can be detected by the cavitation noise estimation from acceleration signals. The accuracy of the cavitation noise estimates is highly dependent on the locations of the pump casing that accelerometers attached on and the cut-off frequency of high pass filtering.

  16. Reduced facial expressiveness in Parkinson's disease: A pure motor disorder?

    Science.gov (United States)

    Ricciardi, Lucia; Bologna, Matteo; Morgante, Francesca; Ricciardi, Diego; Morabito, Bruno; Volpe, Daniele; Martino, Davide; Tessitore, Alessandro; Pomponi, Massimiliano; Bentivoglio, Anna Rita; Bernabei, Roberto; Fasano, Alfonso

    2015-11-15

    Impaired emotional facial expressiveness is an important feature in Parkinson's disease (PD). Although there is evidence of a possible relationship between reduced facial expressiveness and altered emotion recognition or imagery in PD, it is unknown whether other aspects of the emotional processing, such as subjective emotional experience (alexithymia), might influence hypomimia in this condition. In this study wee aimed to investigate possible relationship between reduced facial expressiveness and altered emotion processing (including facial recognition and alexithymia) in patients with PD. Forty PD patients and seventeen healthy controls were evaluated. Facial expressiveness was rated on video recordings, according to the UPDRS-III item 19 and using an ad hoc scale assessing static and dynamic facial expression and posed emotions. Six blind raters evaluated the patients' videos. Emotion facial recognition was tested using the Ekman Test; alexithymia was assessed using Toronto Alexithymia Scale (TAS-20). PD patients had a significantly reduced static and dynamic facial expressiveness and a deficit in posing happiness and surprise. They performed significantly worse than healthy controls in recognizing surprise (p=0.03). The Ekman total score positively correlated with the global expressiveness (R^2=0.39, p=0.01) and with the expressiveness of disgust (R^2=0.32, p=0.01). The occurrence of alexithymia was not different between PD patients and HC; however, a significant negative correlation between the expressiveness of disgust was found for a subscore of TAS (R^2=-.447, p=0.007). Reduced facial expressiveness in PD may be in part related to difficulties with emotional recognition in a context of an unimpaired subjective emotional experience. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Smart Markets for Transferable Pumping Rights

    Science.gov (United States)

    Brozovic, N.; Young, R.

    2016-12-01

    While no national policy on groundwater use exists in the United States, local groundwater management is emerging across the country in response to concerns and conflicts over declining well yields, land subsidence, and the depletion of hydrologically connected surface waters. Management strategies include well drilling moratoria, pumping restrictions, and restrictions on the expansion of irrigated land. To provide flexibility to groundwater users, local regulatory authorities increasingly have begun to allow the transfer of groundwater rights as a cost-effective management tool. Markets can be a versatile risk management tool, helping communities to cope with scarcity, to meet goals for sustainability, and to grow resilient local economies. For example, active groundwater rights transfers exist in the High Plains region of the United States. Yet, several barriers to trade exist: high search costs for interested parties, complicated requirements for regulatory compliance, and reluctance to share sensitive financial information. Additionally, groundwater pumping leads to several kinds of spatial and intertemporal externalities such as stream depletion. Indeed, groundwater management schemes that reallocate water between alternate pumping locations are often explicitly designed to change the distribution and magnitude of pumping externalities. Reallocation may be designed to minimize unwanted impacts on third parties or to encourage trades that reduce the magnitude of externalities. We discuss how smart markets can deal with complex biophysical constraints while also encouraging active trading, therefore ensuring local goals for aquifer sustainability while growing local economies. Smart markets address these issues by providing a centralized hub for trading, automating the process of regulatory compliance by only matching buyers and sellers eligible to trade as specified in the regulations, and maintaining anonymous, confidential bidding.

  18. A magnetocaloric pump for microfluidic applications.

    Science.gov (United States)

    Love, Lonnie J; Jansen, John F; McKnight, Timothy E; Roh, Yul; Phelps, Tommy J

    2004-06-01

    A magnetocaloric pump provides a simple means of pumping fluid using only external thermal and magnetic fields. The principle, which can be traced back to the early work of Rosensweig, is straightforward. Magnetic materials tend to lose their magnetization as the temperature approaches the material's Curie point. Exposing a column of magnetic fluid to a uniform magnetic field coincident with a temperature gradient produces a pressure gradient in the magnetic fluid. As the fluid heats up, it loses its attraction to the magnetic field and is displaced by cooler fluid. The impact of such a phenomenon is obvious: fluid propulsion with no moving mechanical parts. Until recently, limitations in the magnetic and thermal properties of conventional materials severely limited practical operating pressure gradients. However, recent advancements in the design of metal substituted magnetite enable fine control over both the magnetic and thermal properties of magnetic nanoparticles, a key element in colloidal-based magnetic fluids (ferrofluids). This paper begins with a basic description of the process and previous limitations due to material properties. This is followed by a review of existing methods of synthesizing magnetic nanoparticles as well as an introduction to a new approach based on thermophilic metal-reducing bacteria. We compare two compounds and show, experimentally, significant variation in specific magnetic and thermal properties. We develop the constitutive thermal, magnetic, and fluid dynamic equations associated with a magnetocaloric pump and validate our finite-element model with a series of experiments. Preliminary results show a good match between the model and experiment as well as approximately an order of magnitude increase in the fluid flow rate over conventional magnetite-based ferrofluids operating below 80 degrees C. Finally, as a practical demonstration, we describe a novel application of this technology: pumping fluids at the "lab

  19. Method for controlling powertrain pumps

    Science.gov (United States)

    Sime, Karl Andrew; Spohn, Brian L; Demirovic, Besim; Martini, Ryan D; Miller, Jean Marie

    2013-10-22

    A method of controlling a pump supplying a fluid to a transmission includes sensing a requested power and an excess power for a powertrain. The requested power substantially meets the needs of the powertrain, while the excess power is not part of the requested power. The method includes sensing a triggering condition in response to the ability to convert the excess power into heat in the transmission, and determining that an operating temperature of the transmission is below a maximum. The method also includes determining a calibrated baseline and a dissipation command for the pump. The calibrated baseline command is configured to supply the fluid based upon the requested power, and the dissipation command is configured to supply additional fluid and consume the excess power with the pump. The method operates the pump at a combined command, which is equal to the calibrated baseline command plus the dissipation command.

  20. High Performance Space Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — PDT is proposing a High Performance Space Pump based upon an innovative design using several technologies. The design will use a two-stage impeller, high temperature...

  1. Heat pumps at the maltings

    Energy Technology Data Exchange (ETDEWEB)

    1987-11-01

    Heat pumps have halved the energy costs of producing finished malt at two of the country's maltsters. The fuel-fired kilning processes described are now performed by heat pumps with considerable energy and production benefits at the maltings of J.P. Simpson and Co. (Alnwick) Ltd, in Tivetshall St Margaret, Norfolk, and of Munton and Fison Plc of Stowmarket, Suffolk. The heat pump system installed at the Station Malting of J.P. Simpson was devised by the Electricity Council Research Centre at Capenhurst near Chester. Energy cost benefits of Pound 6,000 a month are being realised at Simpsons, but there is the added benefit that the system has been designed to provide conditioned air to the germination cycle to ensure that the correct temperature is maintained throughout the year. At the Cedars factory of Munton and Fison, heat pumps were used on a trial basis for plant micropropagation and for a fish farming unit.

  2. Magnetic heat pump flow director

    Science.gov (United States)

    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.

  3. Transverse pumped laser amplifier architecture

    Science.gov (United States)

    Bayramian, Andrew James; Manes, Kenneth; Deri, Robert; Erlandson, Al; Caird, John; Spaeth, Mary

    2013-07-09

    An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

  4. Novel maglev pump with a combined magnetic bearing.

    Science.gov (United States)

    Onuma, Hiroyuki; Murakami, Michiko; Masuzawa, Toru

    2005-01-01

    The newly developed pump is a magnetically levitated centrifugal blood pump in which active and passive magnetic bearings are integrated to construct a durable ventricular assist device. The developed maglev centrifugal pump consists of an active magnetic bearing, a passive magnetic bearing, a levitated impeller, and a motor stator. The impeller is set between the active magnetic bearing and the motor stator. The active magnetic bearing uses four electromagnets to control the tilt and the axial position of the impeller. The radial movement of the levitated impeller is restricted with the passive stability dependent upon the top stator and the passive permanent magnetic bearing to reduce the energy consumption and the control system complexity. The top stator was designed based upon a magnetic field analysis to develop the maglev pump with sufficient passive stability in the radial direction. By implementing this analysis design, the oscillating amplitude of the impeller in the radial direction was cut in half when compared with the simple shape stator. This study concluded that the newly developed maglev centrifugal pump displayed excellent levitation performance and sufficient pump performance as a ventricular assist device.

  5. History of heat pumps - Swiss contributions and international milestones

    Energy Technology Data Exchange (ETDEWEB)

    Zogg, M.

    2008-05-15

    Compared to conventional boilers, heating by heat pumps cuts down fuel consumption and CO{sub 2} emissions to about 50%. Compared to electric resistance heating, the energy consumption is even reduced up to 80%. Therefore, the impressive market penetration growth of heat pumps will continue. Swiss pioneers were the first to realize functioning vapour recompression plants. The first European heat pumps were realized in Switzerland. To date it remains one of the heat pump champions. Swiss pioneering work in the development of borehole heat exchangers, sewage heat recovery, oil free piston compressors and turbo compressors is well known. The biggest heat pump ever built comes from Switzerland. Although there is a fairly comprehensive natural gas distribution grid, 75% of the new single-family homes built in Switzerland are currently heated by heat pumps. This paper presents some of the highlights of this success story focusing on Swiss developments and relating them to the international milestones. In order to indicate the direction in which the future development might go to, some recent Swiss research projects are presented as well. (author)

  6. Heavy oil pumping : a method to the madness?

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, D. [SAIC Canada Ltd., Ottawa, ON (Canada); MacKay, R. [Canadian Coast Guard, Charlottetown, PE (Canada)

    2002-07-01

    One of the main challenges facing spill response efforts is the pumping of heavy, viscous oils, particularly since most oils tend to weather quickly and form emulsion products at sea. This paper presents the results of an ongoing project which examines new and innovative ways to pump extremely viscous oils. In particular, it describes the heavy oil program experiments at Environment Canada's Environmental Technology Centre, and details recent testing involving skimmers that rely on positive displacement pumping systems to move viscous oil through a test loop. Each run tested parameters such as pressure, flow rate, temperature, viscosity and injection ratios. The effect of simple pumping versus steam injection was also compared. The first phase of the program involved the refloatation of spilled Orimulsion in a specialized tank in which temperature, time, salinity, and concentration of bitumen could be measured. The second phase of testing involved 2 GT skimmers with positive displacement pumps rated for heavy oil processing to recover bitumen through annular water injection. Initial runs through a test loop indicated that the system was capable of producing annular flow and that the addition of steam and hot water injection were having a positive impact on the flow rates. Annular water injection also reduced the pressure requirements during pumping. Several recommendations were made for studies involving the use of steam and hot water injection to improve pumpability of viscous oils. 6 refs., 2 tabs., 3 figs.

  7. Pressure pulsation in roller pumps: a validated lumped parameter model.

    Science.gov (United States)

    Moscato, Francesco; Colacino, Francesco M; Arabia, Maurizio; Danieli, Guido A

    2008-11-01

    During open-heart surgery roller pumps are often used to keep the circulation of blood through the patient body. They present numerous key features, but they suffer from several limitations: (a) they normally deliver uncontrolled pulsatile inlet and outlet pressure; (b) blood damage appears to be more than that encountered with centrifugal pumps. A lumped parameter mathematical model of a roller pump (Sarns 7000, Terumo CVS, Ann Arbor, MI, USA) was developed to dynamically simulate pressures at the pump inlet and outlet in order to clarify the uncontrolled pulsation mechanism. Inlet and outlet pressures obtained by the mathematical model have been compared with those measured in various operating conditions: different rollers' rotating speed, different tube occlusion rates, and different clamping degree at the pump inlet and outlet. Model results agree with measured pressure waveforms, whose oscillations are generated by the tube compression/release mechanism during the rollers' engaging and disengaging phases. Average Euclidean Error (AEE) was 20mmHg and 33mmHg for inlet and outlet pressure estimates, respectively. The normalized AEE never exceeded 0.16. The developed model can be exploited for designing roller pumps with improved performances aimed at reducing the undesired pressure pulsation.

  8. Pump control system for windmills

    Science.gov (United States)

    Avery, Don E.

    1983-01-01

    A windmill control system having lever means, for varying length of stroke of the pump piston, and a control means, responsive to the velocity of the wind to operate the lever means to vary the length of stroke and hence the effective displacement of the pump in accordance with available wind energy, with the control means having a sensing member separate from the windmill disposed in the wind and displaceable thereby in accordance with wind velocity.

  9. Diode-pumped dye laser

    Science.gov (United States)

    Burdukova, O. A.; Gorbunkov, M. V.; Petukhov, V. A.; Semenov, M. A.

    2016-10-01

    This letter reports diode pumping for dye lasers. We offer a pulsed dye laser with an astigmatism-compensated three-mirror cavity and side pumping by blue laser diodes with 200 ns pulse duration. Eight dyes were tested. Four dyes provided a slope efficiency of more than 10% and the highest slope efficiency (18%) was obtained for laser dye Coumarin 540A in benzyl alcohol.

  10. Optical Pumping of Molecular Gases

    Science.gov (United States)

    1976-04-01

    in Hg, excimer system. IV. OPTICALLY PUMPED Na Ř The details of our optical pumping studies of Na2 are presented in Appendix I. The study showed that...inversitot In IM -Second set of linesn have. tentatively been Identified ats D asid A btuu~t-sa A-band tratsitiwts termiuiatitig, oilt*n 3,4,5 for J0 TO HELIUM

  11. Biochemistry of Bacterial Multidrug Efflux Pumps

    Directory of Open Access Journals (Sweden)

    Sanath Kumar

    2012-04-01

    Full Text Available Bacterial pathogens that are multi-drug resistant compromise the effectiveness of treatment when they are the causative agents of infectious disease. These multi-drug resistance mechanisms allow bacteria to survive in the presence of clinically useful antimicrobial agents, thus reducing the efficacy of chemotherapy towards infectious disease. Importantly, active multi-drug efflux is a major mechanism for bacterial pathogen drug resistance. Therefore, because of their overwhelming presence in bacterial pathogens, these active multi-drug efflux mechanisms remain a major area of intense study, so that ultimately measures may be discovered to inhibit these active multi-drug efflux pumps.

  12. 33 CFR 183.524 - Fuel pumps.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Fuel pumps. 183.524 Section 183... SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Equipment Standards § 183.524 Fuel pumps. (a) Each diaphragm pump must not leak fuel from the pump if the primary diaphragm fails. (b) Each...

  13. 14 CFR 29.991 - Fuel pumps.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel pumps. 29.991 Section 29.991... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Fuel System Components § 29.991 Fuel pumps. (a) Compliance with § 29.955 must not be jeopardized by failure of— (1) Any one pump except pumps that...

  14. 46 CFR 181.300 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Fire pumps. 181.300 Section 181.300 Shipping COAST GUARD... EQUIPMENT Fire Main System § 181.300 Fire pumps. (a) A self priming, power driven fire pump must be..., the minimum capacity of the fire pump must be 189 liters (50 gallons) per minute at a pressure of...

  15. 14 CFR 27.991 - Fuel pumps.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel pumps. 27.991 Section 27.991... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Fuel System Components § 27.991 Fuel pumps. Compliance with § 27.955 may not be jeopardized by failure of— (a) Any one pump except pumps that are approved...

  16. 46 CFR 182.520 - Bilge pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Bilge pumps. 182.520 Section 182.520 Shipping COAST...) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.520 Bilge pumps. (a) A vessel must be provided with bilge pumps in accordance with Table 182.520(a). A second power pump is an acceptable alternative to...

  17. 46 CFR 105.20-10 - Pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pumps. 105.20-10 Section 105.20-10 Shipping COAST GUARD... DISPENSING PETROLEUM PRODUCTS Specific Requirements-Cargo Tanks § 105.20-10 Pumps. (a) Pumps for cargo... discharge side of pump if the pressure under shutoff conditions exceeds 60 pounds. When a relief valve...

  18. 14 CFR 25.991 - Fuel pumps.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel pumps. 25.991 Section 25.991... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Fuel System Components § 25.991 Fuel pumps. (a) Main pumps. Each fuel pump required for proper engine operation, or required to meet the fuel...

  19. 46 CFR 118.300 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Fire pumps. 118.300 Section 118.300 Shipping COAST GUARD... Fire pumps. (a) A self priming, power driven fire pump must be installed on each vessel. (b) On a..., the fire pump must be capable of delivering a single hose stream from the highest hydrant, through...

  20. 46 CFR 169.559 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Fire pumps. 169.559 Section 169.559 Shipping COAST GUARD... Firefighting Equipment Firefighting Equipment § 169.559 Fire pumps. (a) Each sailing school vessel must be equipped with fire pumps as required in Table 169.559(a). Table 169.559(a)—Fire Pumps Length Exposed...

  1. METHOD FOR OPTIMIZING THE ENERGY OF PUMPS

    NARCIS (Netherlands)

    Skovmose Kallesøe, Carsten; De Persis, Claudio

    2013-01-01

    The device for energy-optimization on operation of several centrifugal pumps controlled in rotational speed, in a hydraulic installation, begins firstly with determining which pumps as pilot pumps are assigned directly to a consumer and which pumps are hydraulically connected in series upstream of t

  2. Method for optimising the energy of pumps

    NARCIS (Netherlands)

    Skovmose Kallesøe, Carsten; De Persis, Claudio

    2011-01-01

    The method involves determining whether pumps (pu1, pu5) are directly assigned to loads (v1, v3) as pilot pumps (pu2, pu3) and hydraulically connected upstream of the pilot pumps. The upstream pumps are controlled with variable speed for energy optimization. Energy optimization circuits are selected

  3. Numerical Studies On Bubble Pump With Alternate Working Fluids

    Directory of Open Access Journals (Sweden)

    L. Bruno Augustin

    2013-10-01

    Full Text Available The importance of energy conservation in the context of growing global population and dwindling fossil fuel resources cannot be overemphasized. Energy can be conserved by using it more efficiently. The energy spent for an application should be of the correct amount and type. It would make more sense to spend heat energy for heating rather than the high grade electricity as most of the electric power in the world is generated from driving heat engines, for which heat is supplied from the combustion of fossil fuels. At the same time, depletion of these conventional resources also poses a serious problem in meeting energy requirements. In this paper, the bubble pump, which is an integral part of diffusion- absorption refrigeration system, has been investigated numerically .A thermally driven bubble pump, which can be powered by solar thermal energy, is used to lift the liquid. The bubble pump runs on solar energy and reduces the amount of energy spent by replacing the compressor in conventional vapour absorption refrigeration system. As a result of the absence of any mechanical moving part, the refrigerator is silent and very reliable in addition to an economical and environmental friendly device. The concept of such a pump is already in existence but optimization studies are yet to be extensively investigated. This paper deals with the comparison of various parameters of the bubble pump using water and Nonane as the working fluid. Numerical simulation of the bubble pump is carried out using simple numerical equations which assume slug flow in the bubble pump. The mass flow rate, the sensible heating time and position of heating element are varied and the effect it has on diameter of the pipe, pumping ratio and the heat required is studied for both the working fluids

  4. Electron beam pumped semiconductor laser

    Science.gov (United States)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor)

    2009-01-01

    Electron-beam-pumped semiconductor ultra-violet optical sources (ESUVOSs) are disclosed that use ballistic electron pumped wide bandgap semiconductor materials. The sources may produce incoherent radiation and take the form of electron-beam-pumped light emitting triodes (ELETs). The sources may produce coherent radiation and take the form of electron-beam-pumped laser triodes (ELTs). The ELTs may take the form of electron-beam-pumped vertical cavity surface emitting lasers (EVCSEL) or edge emitting electron-beam-pumped lasers (EEELs). The semiconductor medium may take the form of an aluminum gallium nitride alloy that has a mole fraction of aluminum selected to give a desired emission wavelength, diamond, or diamond-like carbon (DLC). The sources may be produced from discrete components that are assembled after their individual formation or they may be produced using batch MEMS-type or semiconductor-type processing techniques to build them up in a whole or partial monolithic manner, or combination thereof.

  5. Investigation of pump and pump switch failures in rainwater harvesting systems

    Science.gov (United States)

    Moglia, Magnus; Gan, Kein; Delbridge, Nathan; Sharma, Ashok K.; Tjandraatmadja, Grace

    2016-07-01

    Rainwater harvesting is an important technology in cities that can contribute to a number of functions, such as sustainable water management in the face of demand growth and drought as well as the detention of rainwater to increase flood protection and reduce damage to waterways. The objective of this article is to investigate the integrity of residential rainwater harvesting systems, drawing on the results of the field inspection of 417 rainwater systems across Melbourne that was combined with a survey of householders' situation, maintenance behaviour and attitudes. Specifically, the study moves beyond the assumption that rainwater systems are always operational and functional and draws on the collected data to explore the various reasons and rates of failure associated with pumps and pump switches, leaving for later further exploration of the failure in other components such as the collection area, gutters, tank, and overflows. To the best of the authors' knowledge, there is no data like this in academic literature or in the water sector. Straightforward Bayesian Network models were constructed in order to analyse the factors contributing to various types of failures, including system age, type of use, the reason for installation, installer, and maintenance behaviour. Results show that a number of issues commonly exist, such as failure of pumps (5% of systems), automatic pump switches that mediate between the tank and reticulated water (9% of systems), and systems with inadequate setups (i.e. no pump) limiting their use. In conclusion, there appears to be a lack of enforcement or quality controls in both installation practices by sometimes unskilled contractors and lack of ongoing maintenance checks. Mechanisms for quality control and asset management are required, but difficult to promote or enforce. Further work is needed into how privately owned assets that have public benefits could be better managed.

  6. Winter coastal upwelling off northwest Borneo in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    YAN Yunwei; LING Zheng; CHEN Changlin

    2015-01-01

    Winter coastal upwelling off northwest Borneo in the South China Sea (SCS) is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem-ber, matures in January, starts to decay in February and almost disappears in March. Both Ekman trans-port induced by the alongshore winter monsoon and Ekman pumping due to orographic wind stress curl are favorable for the upwelling. Transport estimates demonstrate that the month-to-month variability of Ekman transport and Ekman pumping are both consistent with that of winter coastal upwelling, but Ek-man transport is two times larger than Ekman pumping in January and February. Under the influence of El Niño-Southern Oscillation (ENSO), the upwelling shows remarkable interannual variability: during winter of El Niño (La Niña) years, an anticyclonic (a cyclonic) wind anomaly is established in the SCS, which behaves a northeasterly (southwesterly) anomaly and a positive (negative) wind stress curl anomaly off the north-west Borneo coast, enhancing (reducing) the upwelling and causing anomalous surface cooling (warming) and higher (lower) chlorophyll concentration. The sea surface temperature anomaly (SSTA) associated with ENSO off the northwest Borneo coast has an opposite phase to that off southeast Vietnam, resulting in a SSTA seesaw pattern in the southern SCS in winter.

  7. Comparison of solar powered water pumping systems which use diaphragm pumps

    Science.gov (United States)

    Four solar photovoltaic (PV) powered diaphragm pumps were tested at different simulated pumping depths at the USDA-ARS Conservation and Production Research Laboratory near Bushland, Texas. Two of the pumps were designed for intermediate pumping depths (30 to 70 meters), and the other two pumps were...

  8. Measure Guideline. Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States); Easley, S. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States)

    2012-05-01

    This measure guideline evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provides a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  9. Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A.; Easley, S.

    2012-05-01

    The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  10. "Diode Pumped Solid State Lasers At 2 And 3 µm"

    Science.gov (United States)

    Esterowitz, Leon

    1988-06-01

    The most attractive alternative to flashlamp pumping of solid state lasers is the diode laser. In the past two decades numerous laboratory devices have been assembled which incorporated single diode lasers, small laser diode arrays or LED's for pumping of Nd:YAG, Nd:glass and a host of other Nd lasers. The low power output, low packaging density, and extremely high cost of diode lasers prevented any serious applications for laser pumping in the past. The reason for the continued interest in this area stems from the potential dramatic increase in system efficiency and component lifetime, and reduction of thermal load of the solid-state laser material. The latter not only will reduce thereto-optic effects and therefore lead to better beam quality but also will enable an increase in pulse repetition frequency. The attractive operating parameters combined with low voltage operation and the compactness of an all solid-state laser system have a potential high payoff. The high pumping efficiency compared to flashlamps stems from the good spectral match between the laser diode emission and the rare earth activator absorption bands. A significant advantage of laser diode pumping compared to arc lamps is system lifetime and reliability. Laser diode arrays have exhibited lifetimes on the order of 10,000 hours in cw operation and 109 shots in the pulsed mode. Flashlamp life is on the order of 107 shots, and about 200 hours for cw operation. In addition, the high pump flux combined with a substantial UV content in lamp pumped systems causes material degradation in the pump cavity and in the coolant. Such problems are virtually eliminated with laser diode pump sources. The absence of high voltage pulses, high temperatures and UV radiation encountered with arc lamps leads to much more benign operating features for solid state laser systems employing laser diode pumps. Laser diode technology dates back to 1962 when laser action in GaAs diodes was first demonstrated. However, it

  11. The optimisation and analysis of a centrifugal slurry pump impeller with 2 blades

    Directory of Open Access Journals (Sweden)

    Mehmet Salih Cellek

    2013-08-01

    Full Text Available With FLUENT, which is Computational Fluid Dynamics (CFD software, it becomes possible to define the performance of complicated flow in turbo machines like pumps and blowers. It is not only reduced costs but also saves time. This study is aimed to optimize a commercial slurry pump impeller. Therefore, four different types of impellers were designed with using various blade angles, blade length and splitter blade on the impeller, which is the most crucial component of the pump. As a result of analysis it was seen that every impeller affected on the pump performance at different flow rate.

  12. Properties of cat mutually pumped phase conjugation and two-wave mixing gain in doped KNSBN

    Institute of Scientific and Technical Information of China (English)

    Xinguang Xu(许心光); Zongshu Shao(邵宗书); Zhengping Wang(王正平); Junhai Liu(刘均海); Guibao Xu(许贵宝); Dawei Hu(胡大伟)

    2003-01-01

    Cat mutually pumped phase conjugation configuration is discovered and investigated by using two-wavemixing in (KyNa1-y)2z(SrxBa1-x)1-zNb2O6 (KNSBN) crystal. When only one signal or pumped beamdoes not give birth to phase conjugation, the maximum reflectivity of signal and pumped beam attain140% and 30% due to two-wave mixing, respectively. The experimental results show that the two-wavemixing can reduce the threshold of incident beams power, extend the incident angle range, and shortenresponse rate in the process of self-pumped phase conjugator (SPPC) in KNSBN crystal.

  13. Accuracy of a New Patch Pump Based on a Microelectromechanical System (MEMS) Compared to Other Commercially Available Insulin Pumps

    Science.gov (United States)

    Borot, Sophie; Franc, Sylvia; Cristante, Justine; Penfornis, Alfred; Benhamou, Pierre-Yves; Guerci, Bruno; Hanaire, Hélène; Renard, Eric; Reznik, Yves; Simon, Chantal

    2014-01-01

    The JewelPUMP™ (JP) is a new patch pump based on a microelectromechanical system that operates without any plunger. The study aimed to evaluate the infusion accuracy of the JP in vitro and in vivo. For the in vitro studies, commercially available pumps meeting the ISO standard were compared to the JP: the MiniMed® Paradigm® 712 (MP), Accu-Chek® Combo (AC), OmniPod® (OP), Animas® Vibe™ (AN). Pump accuracy was measured over 24 hours using a continuous microweighing method, at 0.1 and 1 IU/h basal rates. The occlusion alarm threshold was measured after a catheter occlusion. The JP, filled with physiological serum, was then tested in 13 patients with type 1 diabetes simultaneously with their own pump for 2 days. The weight difference was used to calculate the infused insulin volume. The JP showed reduced absolute median error rate in vitro over a 15-minute observation window compared to other pumps (1 IU/h): ±1.02% (JP) vs ±1.60% (AN), ±1.66% (AC), ±2.22% (MP), and ±4.63% (OP), P pumps: 21 (19; 25) minutes vs 90 (85; 95), 58 (42; 74), and 143 (132; 218) minutes (AN, AC, MP), P pumps (–2.2 ± 5.6% vs –0.37 ± 4.0%, P = .25). The JP was found to be easier to wear than conventional pumps. The JP is more precise over a short time period, more sensitive to catheter occlusion, well accepted by patients, and consequently, of potential interest for a closed-loop insulin delivery system. PMID:25079676

  14. Dietary Inulin Fibers Prevent Proton-Pump Inhibitor (PPI)-Induced Hypocalcemia in Mice

    NARCIS (Netherlands)

    Hess, M.W.; Baaij, J.H.F. de; Gommers, L.M.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2015-01-01

    BACKGROUND: Proton-pump inhibitor-induced hypomagnesemia (PPIH) is the most recognized side effect of proton-pump inhibitors (PPIs). Additionally, PPIH is associated with hypocalcemia and hypokalemia. It is hypothesized that PPIs reduce epithelial proton secretion and thereby increase the pH in the

  15. Dietary Inulin Fibers Prevent Proton-Pump Inhibitor (PPI)-Induced Hypocalcemia in Mice

    NARCIS (Netherlands)

    Hess, M.W.; Baaij, J.H.F. de; Gommers, L.M.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2015-01-01

    BACKGROUND: Proton-pump inhibitor-induced hypomagnesemia (PPIH) is the most recognized side effect of proton-pump inhibitors (PPIs). Additionally, PPIH is associated with hypocalcemia and hypokalemia. It is hypothesized that PPIs reduce epithelial proton secretion and thereby increase the pH in the

  16. The big squeeze : multi-phase pumping technology aims to increase recovery rates from aging fields

    Energy Technology Data Exchange (ETDEWEB)

    Ross, E.

    2008-04-15

    New technologies developed to assist with offshore oil and gas activities were discussed. The BP King multi-phase pumping project in the Gulf of Mexico is now expecting to enhance production by 20 per cent and extend the life of its field by 5 years through the use of multibooster pumps installed in 2007. The subsea boosting technology has reduced back pressure on the wells and increased oil recovery rates. Multi-phase pumping increased the distance over which the wellstream could be transported. The pump consisted of 4 main components: (1) a motor barrel; (2) a motor cartridge; (3) a pump barrel; and (4) a twin screw pump cartridge. The twin screw product has the ability to pump oil and gas streams with a range of gas void fractions. The pump is self-priming and runs at a relatively low rate. Changes to the pitch and diameter of the screw are used to control the volume of flow and the pressure. The project is also using a long-distance, high voltage distribution system to control multiple pumps at different speeds. The power umbilical system was developed to provide delivery lines for hydraulic fluids, and the umbilical cords also house a fibre-optic communications system to ensure high speed pump response. 3 figs.

  17. Experimental Realization of a Quantum Spin Pump

    DEFF Research Database (Denmark)

    Watson, Susan; Potok, R.; M. Marcus, C.;

    2003-01-01

    We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic fluctuations of pumped current, made spin......-dependent by the application of an in-plane Zeeman field. Spin currents are measured by placing the pump in a focusing geometry with a spin-selective collector....

  18. Adjustment of the basin-scale circulation at 26° N to variations in Gulf Stream, deep western boundary current and Ekman transports as observed by the Rapid array

    Directory of Open Access Journals (Sweden)

    S. A. Cunningham

    2009-04-01

    Full Text Available The Rapid instrument array across the Atlantic Ocean along 26° N provides unprecedented monitoring of the basin-scale circulation. A unique feature of the Rapid array is the combination of full-depth moorings with instruments measuring temperature, salinity, pressure time series at many depths with co-located bottom pressure measurements so that dynamic pressure can be measured from surface to bottom. Bottom pressure measurements show a zonally uniform rise (and fall of bottom pressure of 0.015 dbar on a 5 to 10 day time scale, suggesting that the Atlantic basin is filling and draining on a short time scale. After removing the zonally uniform bottom pressure fluctuations, bottom pressure variations at 4000 m depth against the western boundary compensate instantaneously for baroclinic fluctuations in the strength and structure of the deep western boundary current so there is no basin-scale mass imbalance resulting from variations in the deep western boundary current. After removing the mass compensating bottom pressure, residual bottom pressure fluctuations at the western boundary just east of the Bahamas balance variations in Gulf Stream transport. Again the compensation appears to be especially confined close to the western boundary. Thus, fluctuations in either Gulf Stream or deep western boundary current transports are compensated in a depth independent (barotropic manner very close to the continental slope off the Bahamas. In contrast, compensation for variations in wind-driven surface Ekman transport appears to involve fluctuations in both western basin and eastern basin bottom pressures, though the bottom pressure difference fluctuations appear to be a factor of 3 too large, perhaps due to an inability to resolve small bottom pressure fluctuations after removal of larger zonal average, baroclinic, and Gulf Stream pressure components. For 4 tall moorings where time series dynamic height (geostrophic pressure profiles can be estimated from

  19. Optimal design of multi-conditions for axial flow pump

    Science.gov (United States)

    Shi, L. J.; Tang, F. P.; Liu, C.; Xie, R. S.; Zhang, W. P.

    2016-11-01

    Passage components of the pump device will have a negative flow state when axial pump run off the design condition. Combined with model tests of axial flow pump, this paper use numerical simulation and numerical optimization techniques, and change geometric design parameters of the impeller to optimal design of multi conditions for Axial Flow Pump, in order to improve the efficiency of non-design conditions, broad the high efficient district and reduce operating cost. The results show that, efficiency curve of optimized significantly wider than the initial one without optimization. The efficiency of low flow working point increased by about 2.6%, the designed working point increased by about 0.5%, and the high flow working point increased the most, about 7.4%. The change range of head is small, so all working point can meet the operational requirements. That will greatly reduce operating costs and shorten the period of optimal design. This paper adopted the CFD simulation as the subject analysis, combined with experiment study, instead of artificial way of optimization design with experience, which proves the reliability and efficiency of the optimization design of multi-operation conditions of axial-flow pump device.

  20. Experimental Investigation and Passive Flow Control of a Cavitating Centrifugal Pump

    Directory of Open Access Journals (Sweden)

    Spyridon D. Kyparissis

    2012-01-01

    Full Text Available Passive flow control techniques are used to improve the flow field and efficiency of centrifugal pumps and turbomachines, in general. An important phenomenon that mechanical engineers have to take into account is cavitation. It leads to the decrease of the pump performance and total head. In the present experimental study, a centrifugal pump is investigated in cavitating conditions. A passive flow control is realized using three different blade leading edge angles in order to reduce the cavitation development and enhance the pump performance. The experiments are carried out in a pump test rig specially designed and constructed, along with the impellers. The head drop and total efficiency curves are presented in order to examine the effect of the blade leading edge angle on the cavitation and pump performance. Finally, the vapour distribution along with the blades is illustrated for the tested blade leading edge angles.

  1. Development of the Floating Centrifugal Pump by Use of Non Contact Magnetic Drive and Its Performance

    Directory of Open Access Journals (Sweden)

    Mitsuo Uno

    2004-01-01

    Full Text Available This article focuses on the impeller construction, non contact driving method and performance of a newly developed shaftless floating pump with centrifugal impeller. The drive principle of the floating impeller pump used the magnet induction method similar to the levitation theory of the linear motor. In order to reduce the axial thrust by the pressure different between shroud and disk side, the balance hole and the aileron blade were installed in the floating impeller. Considering the above effect, floating of an impeller in a pump was realized. Moreover, the performance curves of a developed pump are in agreement with a general centrifugal pump, and the dimensionless characteristic curve also agrees under the different rotational speed due to no mechanical friction of the rotational part. Therefore, utility of a non contacting magnetic-drive style pump with the floating impeller was made clear.

  2. Displacement Pumping of Liquids Radially Inward on Centrifugal Microfluidic Platforms in Motion

    Directory of Open Access Journals (Sweden)

    Eric D. Salin

    2011-12-01

    Full Text Available We describe two novel centrifugal microfluidic platform designs that enable passive pumping of liquids radially inward while the platform is in motion. The first design uses an immiscible liquid to displace an aqueous solution back towards the center of the platform, while the second design uses an arbitrary pumping liquid with a volume of air between it and the solution being pumped. Both designs demonstrated the ability to effectively pump 55% to 60% of the solution radially inward at rotational frequencies as low as 400 rpm (6.7 Hz to 700 rpm (11.7 Hz. The pumping operations reached completion within 120 s and 400 s respectively. These platform designs for passive pumping of liquids do not require moving parts or complex fabrication techniques. They offer great potential for increasing the number of sequential operations that can be performed on centrifugal microfluidic platforms, thereby reducing a fundamental limitation often associated with these platforms.

  3. Simple highly efficient pumping configuration in high-power thin-disk laser

    Science.gov (United States)

    Seyedzamani, Sasan; Eslami, Esmaeil

    2017-08-01

    A simple high-power thin-disk pumping configuration using a radiation combination of four commercially available laser-diode stacks is introduced. Two setup modifications are presented to compensate the nonsuitable shape of the pumping spot arising from low beam quality in our combination method. The effects of setup modifications on pumping spot shapes are confirmed by ray tracing simulations using Trace-pro™ software. All setups are arranged in the laboratory, and the experimental measurements show pumping spots improvements on the disk due to modifications in agreement with simulation results. Output power measurements show that by adapting the pumping spot size to the disk cooling capacity the modified setups can deliver higher output powers and efficiencies. Furthermore, the modifications reduce the laser threshold and improve output laser beam quality. Hence, the modifications make the simple four laser-diodes beam combination applicable for thin-disk laser pumping.

  4. Optimized Pump Power Ratio on 2nd Order Pumping Discrete Raman Amplifier

    Institute of Scientific and Technical Information of China (English)

    Renxiang; Huang; Youichi; Akasaka; David; L.; Harris; James; Pan

    2003-01-01

    By optimizing pump power ratio between 1st order backward pump and 2nd order forward pump on discrete Raman amplifier, we demonstrated over 2dB noise figure improvement without excessive non-linearity degradation.

  5. Effects of Crust Ingestion on Mixer Pump Performance in Tank 241-SY-101: Workshop Results

    Energy Technology Data Exchange (ETDEWEB)

    Brennen, C.E.; Stewart, C.W.; Meyer, P.A.

    1999-10-20

    In August 1999, a workshop was held at Pacific Northwest National Laboratory to discuss the effects of crust ingestion on mixer pump performance in Hanford Waste Tank 241-SY-101. The main purpose of the workshop was to evaluate the potential for crust ingestion to degrade mixing and/or damage the mixer pump. The need for a previously determined 12-inch separation between the top of the mixer pump inlet and the crust base was evaluated. Participants included a representative from the pump manufacturer, an internationally known expert in centrifugal pump theory, Hanford scientists and engineers, and operational specialists representing relevant fields of expertise. The workshop focused on developing an understanding of the pump design, addressing the physics of entrainment of solids and gases into the pump, and assessing the effects of solids and gases on pump performance. The major conclusions are summarized as follows: (1) Entrainment of a moderate amount of solids or gas from the crust should not damage the pump or reduce its lifetime, though mixing effectiveness will be somewhat reduced. (2) Air binding should not damage the pump. Vibrations due to ingestion of gas, solids, and objects potentially could cause radial loads that might reduce the lifetime of bearings and seals. However, significant damage would require extreme conditions not associated with the small bubbles, fine solids, and chunks of relatively weak material typical of the crust. (3) The inlet duct extension opening, 235 inches from the tank bottom, should be considered the pump inlet, not the small gap at 262 inches. (4) A suction vortex exists at the inlet of all pumps. The characteristics of the inlet suction vortex in the mixer pump are very hard to predict, but its effects likely extend upward several feet. Because of this, the current 12-inch limit should be replaced with criteria based on actual monitored pump performance. The most obvious criterion (in addition to current operational

  6. Operating pumps on minimum flow

    Energy Technology Data Exchange (ETDEWEB)

    Casada, D.A. [Oak Ridge National Lab., TN (United States); Li, Y.C. [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-06-01

    The Nuclear Regulatory Commission (NRC) staff issued Information Notice (IN) 87-59 to alert all licensees to two miniflow design concerns identified by Westinghouse. The first potential problem discussed in this IN involves parallel pump operation. If the head/capacity curve of one of the parallel pumps is greater than the other, the weaker pump may be dead-headed when the pumps are operating at low-flow conditions. The other problem related to potential pump damage as a result of hydraulic instability during low-flow operation. In NRC Bulletin 88-04, dated May 5, 1988, the staff requested all licensees to investigate and correct, as applicable, the two miniflow design concerns. The staff also developed a Temporary Instruction, Tl 2515/105, dated January 29, 1990 to inspect for the adequacy of licensee response and follow-up actions to NRC Bulletin 88-04. Oak Ridge National Laboratory has reviewed utility responses to Bulletin 88-04 under auspices of the NRC`s Nuclear Plant Aging Research Program, and participated in several NRC inspections. Examples of actions that have been taken, an assessment of the overall industry response, and resultant conclusions and recommendations are presented.

  7. Operating pumps on minimum flow

    Energy Technology Data Exchange (ETDEWEB)

    Casada, D.A. (Oak Ridge National Lab., TN (United States)); Li, Y.C. (Nuclear Regulatory Commission, Washington, DC (United States))

    1992-01-01

    The Nuclear Regulatory Commission (NRC) staff issued Information Notice (IN) 87-59 to alert all licensees to two miniflow design concerns identified by Westinghouse. The first potential problem discussed in this IN involves parallel pump operation. If the head/capacity curve of one of the parallel pumps is greater than the other, the weaker pump may be dead-headed when the pumps are operating at low-flow conditions. The other problem related to potential pump damage as a result of hydraulic instability during low-flow operation. In NRC Bulletin 88-04, dated May 5, 1988, the staff requested all licensees to investigate and correct, as applicable, the two miniflow design concerns. The staff also developed a Temporary Instruction, Tl 2515/105, dated January 29, 1990 to inspect for the adequacy of licensee response and follow-up actions to NRC Bulletin 88-04. Oak Ridge National Laboratory has reviewed utility responses to Bulletin 88-04 under auspices of the NRC's Nuclear Plant Aging Research Program, and participated in several NRC inspections. Examples of actions that have been taken, an assessment of the overall industry response, and resultant conclusions and recommendations are presented.

  8. The lunar thermal ice pump

    Energy Technology Data Exchange (ETDEWEB)

    Schorghofer, Norbert [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii, Honolulu, HI 96822 (United States); Aharonson, Oded, E-mail: norbert@hawaii.edu [Helen Kimmel Center for Planetary Science, Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 76100 (Israel)

    2014-06-20

    It has long been suggested that water ice can exist in extremely cold regions near the lunar poles, where sublimation loss is negligible. The geographic distribution of H-bearing regolith shows only a partial or ambiguous correlation with permanently shadowed areas, thus suggesting that another mechanism may contribute to locally enhancing water concentrations. We show that under suitable conditions, water molecules can be pumped down into the regolith by day-night temperature cycles, leading to an enrichment of H{sub 2}O in excess of the surface concentration. Ideal conditions for pumping are estimated and found to occur where the mean surface temperature is below 105 K and the peak surface temperature is above 120 K. These conditions complement those of the classical cold traps that are roughly defined by peak temperatures lower than 120 K. On the present-day Moon, an estimated 0.8% of the global surface area experiences such temperature variations. Typically, pumping occurs on pole-facing slopes in small areas, but within a few degrees of each pole the equator-facing slopes are preferred. Although pumping of water molecules is expected over cumulatively large areas, the absolute yield of this pump is low; at best, a few percent of the H{sub 2}O delivered to the surface could have accumulated in the near-surface layer in this way. The amount of ice increases with vapor diffusivity and is thus higher in the regolith with large pore spaces.

  9. Experimental Investigation of a Rectangular Airlift Pump

    Directory of Open Access Journals (Sweden)

    I. I. Esen

    2010-01-01

    Full Text Available Hydraulic performance of an airlift pump having a rectangular cross-section 20 mm × 80 mm was investigated through an experimental program. The pump was operated at six different submergence ratios and the liquid flow rate was measured at various flowrates of air injected. The effectiveness of the pump, defined as the ratio of the mass of liquid pumped to the mass of air injected, was determined as a function of the mass of air injected for different submergence ratios. Results obtained were compared with those for circular airlift pumps using an analytical model for circular pumps. Effectiveness of the rectangular airlift pump was observed to be comparable to that of the circular pumps. Hydraulic performance of the rectangular airlift pump investigated was then described by a set of semilogarithmic empirical equations.

  10. Heat pumps; Synergy of high efficiency and low carbon electricity

    Energy Technology Data Exchange (ETDEWEB)

    Koike, Akio

    2010-09-15

    Heat pump is attracting wide attention for its high efficiency to utilize inexhaustible and renewable ambient heat in the environment. With its rapid innovation and efficiency improvement, this technology has a huge potential to reduce CO2 emissions by replacing currently widespread fossil fuel combustion systems to meet various heat demands from the residential, commercial and industrial sectors. Barriers to deployment such as low public awareness and a relatively long pay-back period do exist, so it is strongly recommended that each country implement policies to promote heat pumps as a renewable energy option and an effective method to combat global warming.

  11. Harnessing geothermal energy with heat pumps : a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Arisi, J.A. [Memorial Univ. of Newfoundland, St. John' s, NL (Canada). Dept. of Civil Engineering

    2009-07-01

    Fossil fuel combustion emits large amounts of greenhouse gases (GHGs) into the atmosphere. Renewable fuel sources that do not have a negative impact on the environment are needed to reduce the risk of climatic change. This abstract discussed recent research related to geothermal energy. Two types of geothermal energy were investigated: (1) deep underground heat using turbines to produce electricity; and (2) shallow depth heat using heat pumps to provide space heating. A review of recent research on shallow depth heat harnessing was presented. The costs and GHG emission reductions related to the installation of a geothermal heat pump system for space heating were also discussed.

  12. Novel Characteristics of Valveless Pumping

    DEFF Research Database (Denmark)

    Timmermann, Stine; Ottesen, Johnny T.

    2009-01-01

    direction depends on the pumping frequency. We propose a relation between wave propagation velocity, tube length, and resonance frequencies associated with shifts in the pumping direction using numerical simulations. The eigenfrequencies of the system are estimated from the linearized system, and we show......This study investigates the occurrence of valveless pumping in a fluidfilled system consisting of two open tanks connected by an elastic tube. We show that directional flow can be achieved by introducing a periodic pinching applied at an asymmetrical location along the tube, and that the flow...... that these eigenfrequencies constitute the resonance frequencies and the horizontal slope frequencies of the system; 'horizontal slope frequency' being a new concept. A simple model is suggested, explaining the effect of the gravity driven part of the oscillation observed in response to the tank and tube diameter changes...

  13. Multistage quantum absorption heat pumps

    Science.gov (United States)

    Correa, Luis A.

    2014-04-01

    It is well known that heat pumps, while being all limited by the same basic thermodynamic laws, may find realization on systems as "small" and "quantum" as a three-level maser. In order to quantitatively assess how the performance of these devices scales with their size, we design generalized N-dimensional ideal heat pumps by merging N -2 elementary three-level stages. We set them to operate in the absorption chiller mode between given hot and cold baths and study their maximum achievable cooling power and the corresponding efficiency as a function of N. While the efficiency at maximum power is roughly size-independent, the power itself slightly increases with the dimension, quickly saturating to a constant. Thus, interestingly, scaling up autonomous quantum heat pumps does not render a significant enhancement beyond the optimal double-stage configuration.

  14. Piston-assisted charge pumping

    CERN Document Server

    Kaur, D; Mourokh, L

    2015-01-01

    We examine charge transport through a system of three sites connected in series in the situation when an oscillating charged piston modulates the energy of the middle site. We show that with an appropriate set of parameters, charge can be transferred against an applied voltage. In this scenario, when the oscillating piston shifts away from the middle site, the energy of the site decreases and it is populated by a charge transferred from the lower energy site. On the other hand, when the piston returns to close proximity, the energy of the middle site increases and it is depopulated by the higher energy site. Thus through this process, the charge is pumped against the potential gradient. Our results can explain the process of proton pumping in one of the mitochondrial enzymes, Complex I. Moreover, this mechanism can be used for electron pumping in semiconductor nanostructures.

  15. Multi-channel peristaltic pump for microfluidic applications featuring monolithic PDMS inlay

    DEFF Research Database (Denmark)

    Skafte-Pedersen, Peder; Sabourin, David; Dufva, Martin

    2009-01-01

    The design, fabrication and characterization of a miniaturized, mechanically-actuated 12-channel peristaltic pump for microfluidic applications and built from simple, low-cost materials and fabrication methods is presented. Two pump configurations are tested, including one which reduces pulsating...... flow. Both use a monolithic PDMS pumping inlay featuring three-dimensional geometries favourable to pumping applications and 12 wholly integrated circular channels. Flow rates in the sub-µL min-1 to µL min-1 range were obtained. Channel-to-channel flow rate variability was comparable to a commercial...... pumping system at lower flow rates. The small footprint, 40 mm by 80 mm, of the micropump renders it portable, and allows its use on microscope stages adjacent to microfluidic devices, thus reducing system dead volumes. The micropump's design allows potential use in remote and resource-limited locations...

  16. Multi-channel peristaltic pump for microfluidic applications featuring monolithic PDMS inlay

    DEFF Research Database (Denmark)

    Skafte-Pedersen, Peder; Sabourin, David; Dufva, Martin

    2009-01-01

    The design, fabrication and characterization of a miniaturized, mechanically-actuated 12-channel peristaltic pump for microfluidic applications and built from simple, low-cost materials and fabrication methods is presented. Two pump configurations are tested, including one which reduces pulsating...... flow. Both use a monolithic PDMS pumping inlay featuring three-dimensional geometries favourable to pumping applications and 12 wholly integrated circular channels. Flow rates in the sub-µL min-1 to µL min-1 range were obtained. Channel-to-channel flow rate variability was comparable to a commercial...... pumping system at lower flow rates. The small footprint, 40 mm by 80 mm, of the micropump renders it portable, and allows its use on microscope stages adjacent to microfluidic devices, thus reducing system dead volumes. The micropump's design allows potential use in remote and resource-limited locations...

  17. Evaluation of the 800 nm pump band for erbium-doped fiber amplifiers

    DEFF Research Database (Denmark)

    Pedersen, Bo; Miniscalco, William J.; Zemon, Stanley A.

    1992-01-01

    Performs a comprehensive experimental and theoretical investigation of methods for overcoming the excited-state absorption (ESA), which is the main obstacle to efficient pumping of erbium-doped fiber amplifiers (EDFAs) at 800 nm. The effects of ESA on gain can be reduced at the cost of an additio......Performs a comprehensive experimental and theoretical investigation of methods for overcoming the excited-state absorption (ESA), which is the main obstacle to efficient pumping of erbium-doped fiber amplifiers (EDFAs) at 800 nm. The effects of ESA on gain can be reduced at the cost...... based on a quantitative numerical model. It is predicted that 2-3 dB less pump power is required for the fluorophosphate EDFA. For Al/P-silica EDFAs, it is found that ~7-dB-higher power is required when pumping in the 800 nm band than for pumping at 980 and 1480 nm...

  18. Optical pumping and xenon NMR

    Energy Technology Data Exchange (ETDEWEB)

    Raftery, M. Daniel [Univ. of California, Berkeley, CA (United States)

    1991-11-01

    Nuclear Magnetic Resonance (NMR) spectroscopy of xenon has become an important tool for investigating a wide variety of materials, especially those with high surface area. The sensitivity of its chemical shift to environment, and its chemical inertness and adsorption properties make xenon a particularly useful NMR probe. This work discusses the application of optical pumping to enhance the sensitivity of xenon NMR experiments, thereby allowing them to be used in the study of systems with lower surface area. A novel method of optically-pumping 129Xe in low magnetic field below an NMR spectrometer and subsequent transfer of the gas to high magnetic field is described. NMR studies of the highly polarized gas adsorbed onto powdered samples with low to moderate surface areas are now possible. For instance, NMR studies of optically-pumped xenon adsorbed onto polyacrylic acid show that xenon has a large interaction with the surface. By modeling the low temperature data in terms of a sticking probability and the gas phase xenon-xenon interaction, the diffusion coefficient for xenon at the surface of the polymer is determined. The sensitivity enhancement afforded by optical pumping also allows the NMR observation of xenon thin films frozen onto the inner surfaces of different sample cells. The geometry of the thin films results in interesting line shapes that are due to the bulk magnetic susceptibility of xenon. Experiments are also described that combine optical pumping with optical detection for high sensitivity in low magnetic field to observe the quadrupoler evolution of 131 Xe spins at the surface of the pumping cells. In cells with macroscopic asymmetry, a residual quadrupolar interaction causes a splitting in the 131Xe NMR frequencies in bare Pyrex glass cells and cells with added hydrogen.

  19. Optical pumping and xenon NMR

    Energy Technology Data Exchange (ETDEWEB)

    Raftery, M.D.

    1991-11-01

    Nuclear Magnetic Resonance (NMR) spectroscopy of xenon has become an important tool for investigating a wide variety of materials, especially those with high surface area. The sensitivity of its chemical shift to environment, and its chemical inertness and adsorption properties make xenon a particularly useful NMR probe. This work discusses the application of optical pumping to enhance the sensitivity of xenon NMR experiments, thereby allowing them to be used in the study of systems with lower surface area. A novel method of optically-pumping [sup 129]Xe in low magnetic field below an NMR spectrometer and subsequent transfer of the gas to high magnetic field is described. NMR studies of the highly polarized gas adsorbed onto powdered samples with low to moderate surface areas are now possible. For instance, NMR studies of optically-pumped xenon adsorbed onto polyacrylic acid show that xenon has a large interaction with the surface. By modeling the low temperature data in terms of a sticking probability and the gas phase xenon-xenon interaction, the diffusion coefficient for xenon at the surface of the polymer is determined. The sensitivity enhancement afforded by optical pumping also allows the NMR observation of xenon thin films frozen onto the inner surfaces of different sample cells. The geometry of the thin films results in interesting line shapes that are due to the bulk magnetic susceptibility of xenon. Experiments are also described that combine optical pumping with optical detection for high sensitivity in low magnetic field to observe the quadrupoler evolution of 131 Xe spins at the surface of the pumping cells. In cells with macroscopic asymmetry, a residual quadrupolar interaction causes a splitting in the [sup 131]Xe NMR frequencies in bare Pyrex glass cells and cells with added hydrogen.

  20. Comparative analytics of infusion pump data across multiple hospital systems.

    Science.gov (United States)

    Catlin, Ann Christine; Malloy, William X; Arthur, Karen J; Gaston, Cindy; Young, James; Fernando, Sudheera; Fernando, Ruchith

    2015-02-15

    A Web-based analytics system for conducting inhouse evaluations and cross-facility comparisons of alert data generated by smart infusion pumps is described. The Infusion Pump Informatics (IPI) project, a collaborative effort led by research scientists at Purdue University, was launched in 2009 to provide advanced analytics and tools for workflow analyses to assist hospitals in determining the significance of smart-pump alerts and reducing nuisance alerts. The IPI system allows facility-specific analyses of alert patterns and trends, as well as cross-facility comparisons of alert data uploaded by more than 55 participating institutions using different types of smart pumps. Tools accessible through the IPI portal include (1) charts displaying aggregated or breakout data on the top drugs associated with alerts, numbers of alerts per device or care area, and override-to-alert ratios, (2) investigative reports that can be used to characterize and analyze pump-programming errors in a variety of ways (e.g., by drug, by infusion type, by time of day), and (3) "drill-down" workflow analytics enabling users to evaluate alert patterns—both internally and in relation to patterns at other hospitals—in a quick and efficient stepwise fashion. The formation of the IPI analytics system to support a community of hospitals has been successful in providing sophisticated tools for member facilities to review, investigate, and efficiently analyze smart-pump alert data, not only within a member facility but also across other member facilities, to further enhance smart pump drug library design. Copyright © 2015 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  1. Portable Heat Pump Testing Device

    Directory of Open Access Journals (Sweden)

    Kłosowiak R.

    2015-08-01

    Full Text Available The aim of this paper is to present the design and working principle of a portable testing device for heat pumps in the energy recirculation system. The presented test stand can be used for any refrigerating/reverse flow cycle device to calculate the device energy balance. The equipment is made of two portable containers of the capacity of 250 liters to simulate the air heat source and ground heat source with a system of temperature stabilization, compressor heat pump of the coefficient of performance (COP of = 4.3, a failsafe system and a control and measurement system.

  2. TFCX pumped limiter and vacuum pumping system design and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Haines, J.R.

    1985-04-01

    Impurity control system design and performance studies were performed in support of the Tokamak Fusion Core Experiment (TFCX) pre-conceptual design. Efforts concentrated on pumped limiter and vacuum pumping system design configuration, thermal/mechanical and erosion lifetime performance of the limiter protective surface, and helium ash removal performance. The reference limiter design forms a continuous toroidal belt at the bottom of the device and features a flat surface with a single leading edge. The vacuum pumping system features large vacuum ducts (diameter approximately 1 m) and high-speed, compound cryopumps. Analysis results indicate that the limiter/vacuum pumping system design provides adequate helium ash removal. Erosion, primarily by disruption-induced vaporization and/or melting, limits the protective surface lifetime to about one calendar year or only about 60 full-power hours of operation. In addition to evaluating impurity control system performance for nominal TFCX conditions, these studies attempt to focus on the key plasma physics and engineering design issues that should be addressed in future research and development programs.

  3. Modeling of forward pump EDFA under pump power through MATLAB

    Science.gov (United States)

    Raghuwanshi, Sanjeev Kumar; Sharma, Reena

    2015-05-01

    Optical fiber loss is a limiting factor for high-speed optical network applications. However, the loss can be compensated by variety of optical amplifiers. Raman amplifier and EDFA amplifier are widely used in optical communication systems. There are certain advantages of EDFA over Raman amplifier like amplifying the signal at 1550 nm wavelength at which the fiber loss is minimum. Apart from that there is no pulse walk-off problem with an EDFA amplifier. With the advent of optical amplifiers like EDFA, it is feasible to achieve a high bit rate beyond terabits in optical network applications. In our study, a MATLAB simulink-based forward pumped EDFA (operating in C-band 1525-1565 nm) simulation platform has been devised to evaluate the following performance parameters like gain, noise figure, amplified spontaneous emission power variations of a forward pumped EDFA operating in C-band (1525-1565 nm) as functions of Er3+ fiber length, injected pump power, signal input power, and Er3+ doping density. The effect of an input pump power on gain and noise figure was illustrated graphically. It is possible to completely characterize and optimize the EDFA performance using our dynamic simulink test bed.

  4. Transient Growth of Ekman-Couette Flow

    CERN Document Server

    Shi, Liang; Tilgner, Andreas

    2013-01-01

    Coriolis force effects on shear flows are important in geophysical and astrophysical contexts. We here report a study on the linear stability and the transient energy growth of the plane Couette flow with system rotation perpendicular to the shear direction. External rotation causes linear instability. At small rotation rates, the onset of linear instability scales inversely with the rotation rate and the optimal transient growth in the linearly stable region is slightly enhanced, ~Re^2. The corresponding optimal initial perturbations are characterized by roll structures inclined in the streamwise direction and are twisted under external rotation. At large rotation rates, the transient growth is significantly inhibited and hence linear stability analysis is a reliable indicator for instability.

  5. Dynamic damper pressure fluctuation in the pumping systems

    Directory of Open Access Journals (Sweden)

    O.V. Korolyov

    2016-05-01

    Full Text Available Inertial part of any devices and equipment (e.g., pumps, hung or mounted on the resilient frame and being under the influence of the disturbing force that works at a constant frequency, may be subject to fluctuations, especially near of the resonance area. For elimination these fluctuations, you can resort to the use of a dynamic damper. Aim: The aim of the work is an analytical study of various dynamic dampers to reduce pressure fluctuation problems in pumping systems. Materials and Methods: A comparative analysis of efficiency of functioning was carried out for two types of dynamic dampers - hydraulic and mechanical. Results: The technique for calculating of dynamic damper of fluid pressure fluctuations in the hydraulic and mechanical pumps is presented. Algorithms of calculations are reported to engineering applications and implemented in the production process. The calculations show that the use of dynamic mechanical dampers is expedient at high frequency pumps, and, with increasing frequency of the pump by 6 times, winning in the dimensions of the damper in 3.5 times.

  6. Smart syringe pumps for drug infusion during dental intravenous sedation.

    Science.gov (United States)

    Seo, Kwang-Suk; Lee, Kiyoung

    2016-09-01

    Dentists often sedate patients in order to reduce their dental phobia and stress during dental treatment. Sedatives are administered through various routes such as oral, inhalation, and intravenous routes. Intravenous administration has the advantage of rapid onset of action, predictable duration of action, and easy titration. Typically, midazolam, propofol or dexmedetomidine are used as intravenous sedatives. Administration of these sedatives via infusion by using a syringe pump is more effective and successful than infusing them as a bolus. However, during intravenous infusion of sedatives or opioids using a syringe pump, fatal accidents may occur due to the clinician's carelessness. To prevent such risks, smart syringe pumps have been introduced clinically. They allow clinicians to perform effective sedation by using a computer to control the dose of the drug being infused. To ensure patient safety, various alarm features along with a drug library, which provides drug information and prevents excessive infusion by limiting the dose, have been added to smart pumps. In addition, programmed infusion systems and target-controlled infusion systems have also been developed to enable effective administration of sedatives. Patient-controlled infusion, which allows a patient to control his/her level of sedation through self-infusion, has also been developed. Safer and more successful sedation may be achieved by fully utilizing these new features of the smart pump.

  7. Energy performance and consumption for biogas heat pump air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhenjun [Architectural Engineering College, Qingdao Agricultural University, 266109 (China); Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Tianjin University, Tianjin, 300072 (China); Wu, Huaizhi; Wu, Meiling [Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Tianjin University, Tianjin, 300072 (China)

    2010-12-15

    Biogas engine-driven heat pump air conditioner is a new-style system which includes biogas engine-driven heat pump, primary heat exchanger, second heat exchanger, sprayed room and fans, pumps, etc. In summertime, the air can be reheated by the waste heat water from the biogas engine in the system, while the air can be reheated and humidified by the waste heat water in winter. Reducing or displacing electrical heating requirements can achieve the great opportunity for significant energy savings. This paper, therefore, aims to improve the energy performance of the AC system by using the waste heat from the biogas engine. The mathematic model was used to research the BHPAC. Explicitly, we investigated the influence of various factors including the outdoor air temperature and humidity in summer and winter. Results show that the biogas engine-driven heat pump air conditioner can save more energy than the electrical power heat pump. In summer, the minimum for percentage of primary energy saving for BHPAC is over 25%. With the outdoor air dry-bulb temperature and the relative humidity rises, the saving energy percentage rises. In winter, the minimum for percentage of primary energy saving for BHPAC is 37%. The more the outdoor air relative humidity of the outdoor air decreases, the more the BHPAC saves energy. It is proved that the system which is a highly actively fully utilizing energy technology has good partial load characteristic and good effects of energy saving. (author)

  8. Mitigation of Tank 241-SY-101 by pump mixing: Results of testing phases A and B

    Energy Technology Data Exchange (ETDEWEB)

    Allemann, R.T.; Antoniak, Z.I.; Chvala, W.D.; Friley, J.R.; Gregory, W.B.; Hudson, J.D.; Michener, T.E.; Panisko, F.E.; Stewart, C.W.; Wise, B.M. [Pacific Northwest Lab., Richland, WA (United States); Efferding, L.E.; Fadeff, J.G.; Irwin, J.J.; Kirch, N.W. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-03-01

    A spare mixing pump from the Hanford Grout Program was installed in Hanford double-shell waste Tank 241-SY-101 on July 3, 1993, after being modified to take advantage of waste stratification. It was anticipated that pump mixing would prevent large episodic flammable gas releases that had been occurring about every 100-150 days. A cautious initial test plan, called Phase A, was run to find how the pump and tank would behave in response to very brief and gentle pump operation. No large gas releases were triggered, and the pump performed well except for two incidents of nozzle plugging. On October 21, 1993, the next test series, Phase B, began, and the pump was applied more aggressively to mix the tank contents and mitigate uncontrolled gas releases. Orienting the pump in new directions released large volumes of gas and reduced the waste level to a near-record low. Results of the entire period from pump installation to the end of Phase B on December 17, 1993, are presented in detail in this document. Though long-term effects require further evaluation, we conclude from these data that the jet mixer pump is an effective means of controlling flammable gas release and that it has met the success criteria for mitigation in this tank.

  9. Energy consumption behavior of submersible pumps using in the Barind area of Bangladesh

    Science.gov (United States)

    Haque, M. E.; Islam, M. R.; Masud, M. H.; Ferdous, J.; Haniu, H.

    2017-06-01

    In this work the ground water level and water pumping for irrigation and drinking purposes in Barind area of Bangladesh have been studied. The depth of ground water level remains under 30ft throughout the year that enforcing the use of submersible pumps in most parts of Barind zone. The Barind Multipurpose Development Authority (BMDA) and Rajshahi WASA are the major water supplying authority in the Northern Part of Bangladesh by using 14386 and 87 nos of submersible pumps, respectively. An investigation for the values of life cycle cost elements of submersible pumps has also been carried out. The performance of the pumps running in different sites in Barind area were investigated and compared with the lab test results of new pumps. Energy consumption cost is dominating the life cycle cost of the pumps using in Barind region and improper matching of pump standard running conditions and operation/system requirements are the main causes of lower efficiency. It is found that the efficiency of the running pumps is reduced by 20 - 40% than that of lab test results.

  10. Commercial Submersible Mixing Pump For SRS Tank Waste Removal - 15223

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Mike [Savannah River Remediation, LLC., Aiken, SC (United States); Herbert, James E. [Savannah River Remediation, LLC., Aiken, SC (United States); Scheele, Patrick W. [Savannah River Remediation, LLC., Aiken, SC (United States)

    2015-01-12

    product lubricated canned motor pumps designed to fit within available risers and have significant agitation capabilities to suspend waste solids. Waste removal and closure of two tanks has been accomplished with agitation provided by 3 SMPs installed within the tanks. In 2012, a team was assembled to investigate alternative solids removal technologies to support waste removal for closing tanks. The goal of the team was to find a more cost effective approach that could be used to replace the current mixing pump technology. This team was unable to identify an alternative technology outside of mixing pumps to support waste agitation and removal from SRS waste tanks. However, the team did identify a potentially lower cost mixing pump compared to the baseline SLPs and SMPs. Rather than using the traditional procurement using an engineering specification, the team proposed to seek commercially available submersible mixer pumps (CSMP) as alternatives to SLPs and SMPs. SLPs and SMPs have a high procurement cost and the actual cost of moving pumps between tanks has shown to be significantly higher than the original estimates that justified the reuse of SMPs and SLPs. The team recommended procurement of “off-the-shelf” industry pumps which may be available for significant savings, but at an increased risk of failure and reduced operating life in the waste tank. The goal of the CSMP program is to obtain mixing pumps that could mix from bulk waste removal through tank closure and then be abandoned in place as part of tank closure. This paper will present the development, progress and relative advantages of the CSMP.

  11. Adjustment of the basin-scale circulation at 26° N to variations in Gulf Stream, deep western boundary current and Ekman transports as observed by the Rapid array

    Directory of Open Access Journals (Sweden)

    S. A. Cunningham

    2009-10-01

    Full Text Available The Rapid instrument array across the Atlantic Ocean along 26° N provides unprecedented monitoring of the basin-scale circulation. A unique feature of the Rapid array is the combination of full-depth moorings with instruments measuring temperature, salinity, pressure time series at many depths with co-located bottom pressure measurements so that dynamic pressure can be measured from surface to bottom. Bottom pressure measurements show a zonally uniform rise (and fall of bottom pressure of 0.015 dbar on a 5 to 10 day time scale, suggesting that the Atlantic basin is filling and draining on a short time scale. After removing the zonally uniform bottom pressure fluctuations, bottom pressure variations at 4000 m depth against the western boundary compensate instantaneously for baroclinic fluctuations in the strength and structure of the deep western boundary current so there is no basin-scale mass imbalance resulting from variations in the deep western boundary current. After removing the mass compensating bottom pressure, residual bottom pressure fluctuations at the western boundary just east of the Bahamas balance variations in Gulf Stream transport. Again the compensation appears to be especially confined close to the western boundary. Thus, fluctuations in either Gulf Stream or deep western boundary current transports are compensated in a depth independent (barotropic manner very close to the continental slope off the Bahamas. In contrast, compensation for variations in wind-driven surface Ekman transport appears to involve fluctuations in both western basin and eastern basin bottom pressures, though the bottom pressure difference fluctuations appear to be a factor of 3 too large, perhaps due to an inability to resolve small bottom pressure fluctuations after removal of larger zonal average, baroclinic, and Gulf Stream pressure components. For 4 tall moorings where time series dynamic height (geostrophic pressure profiles can be estimated from

  12. Proton pump inhibitors and gastroenteritis

    NARCIS (Netherlands)

    R.J. Hassing (Robert); A. Verbon (Annelies); H. de Visser (Herman); A. Hofman (Albert); B.H.Ch. Stricker (Bruno)

    2016-01-01

    textabstractAn association between proton pump inhibitor (PPI) therapy and bacterial gastroenteritis has been suggested as well as contradicted. The aim of this study was to examine the association between the use of PPIs and occurrence of bacterial gastroenteritis in the prospective Rotterdam Study

  13. Cotransporters as molecular water pumps

    DEFF Research Database (Denmark)

    Zeuthen, Thomas; MacAulay, Nanna

    2002-01-01

    Molecular water pumps are membrane proteins of the cotransport type in which a flux of water is coupled to substrate fluxes by a mechanism within the protein. Free energy can be exchanged between the fluxes. Accordingly, the flux of water may be relatively independent of the external water chemical...

  14. Nuclear pumped gas laser research

    Science.gov (United States)

    Thom, K.

    1976-01-01

    Nuclear pumping of lasers by fission-fragments from nuclear chain reactions is discussed. Application of the newly developed lasers to spacecraft propulsion or onboard power, to lunar bases for industrial processing, and to earth for utilization of power without pollution and hazards is envisioned. Emphasis is placed on the process by which the fission-fragement kinetic energy is converted into laser light.

  15. Heat Radiators for Electromagnetic Pumps

    Science.gov (United States)

    Campana, R. J.

    1986-01-01

    Report proposes use of carbon/carbon composite radiators in electromagnetic coolant pumps of nuclear reactors on spacecraft. Carbon/carbon composite materials function well at temperatures in excess of 2,200 K. Aluminum has melting temperature of only 880 K.

  16. Pierre Gorce working on a helium pump.

    CERN Multimedia

    1975-01-01

    This type of pump was designed by Mario Morpurgo, to circulate liquid helium in superconducting magnets wound with hollow conductors. M. Morpurgo, Design and construction of a pump for liquid helium, CRYIOGENICS, February 1977, p. 91

  17. Human Aorta Is a Passive Pump

    Science.gov (United States)

    Pahlevan, Niema; Gharib, Morteza

    2012-11-01

    Impedance pump is a simple valveless pumping mechanism that operates based on the principles of wave propagation and reflection. It has been shown in a zebrafish that a similar mechanism is responsible for the pumping action in the embryonic heart during early stages before valve formation. Recent studies suggest that the cardiovascular system is designed to take advantage of wave propagation and reflection phenomena in the arterial network. Our aim in this study was to examine if the human aorta is a passive pump working like an impedance pump. A hydraulic model with different compliant models of artificial aorta was used for series of in-vitro experiments. The hydraulic model includes a piston pump that generates the waves. Our result indicates that wave propagation and reflection can create pumping mechanism in a compliant aorta. Similar to an impedance pump, the net flow and the flow direction depends on the frequency of the waves, compliance of the aorta, and the piston stroke.

  18. Compact and highly efficient laser pump cavity

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jim J. (Dublin, CA); Bass, Isaac L. (Castro Valley, CA); Zapata, Luis E. (Livermore, CA)

    1999-01-01

    A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

  19. Nuclear power plant safety related pump issues

    Energy Technology Data Exchange (ETDEWEB)

    Colaccino, J.

    1996-12-01

    This paper summarizes of a number of pump issues raised since the Third NRC/ASME Symposium on Valve and Pump Testing in 1994. General issues discussed include revision of NRC Inspection Procedure 73756, issuance of NRC Information Notice 95-08 on ultrasonic flow meter uncertainties, relief requests for tests that are determined by the licensee to be impractical, and items in the ASME OM-1995 Code, Subsection ISTB, for pumps. The paper also discusses current pump vibration issues encountered in relief requests and plant inspections - which include smooth running pumps, absolute vibration limits, and vertical centrifugal pump vibration measurement requirements. Two pump scope issues involving boiling water reactor waterlog and reactor core isolation cooling pumps are also discussed. Where appropriate, NRC guidance is discussed.

  20. Asymmetrically pumped Bragg scattering with the effects of nonlinear phase modulation

    DEFF Research Database (Denmark)

    Andersen, Lasse Mejling; Friis, Søren Michael Mørk; Reddy, Dileep V.

    2014-01-01

    We derive exact solutions to asymmetrically pumped Bragg scattering with nonlinear phase-modulation (NPM) and show that this setup allows for the frequency conversion of many temporal modes, while reducing the effects due to NPM.......We derive exact solutions to asymmetrically pumped Bragg scattering with nonlinear phase-modulation (NPM) and show that this setup allows for the frequency conversion of many temporal modes, while reducing the effects due to NPM....

  1. Experience in reducing the hemolysis of an impeller assist heart.

    Science.gov (United States)

    Qian, K X

    1989-01-01

    Blood trauma has been one of the main problems of centrifugal pumps. The difficulties in reducing hemolysis are many, and all the factors causing excessive hemolysis always act together, making them difficult to discover and distinguish. Furthermore, error could occur at many points during hemolysis testing, making it difficult to repeat results. In developing the low hemolysis pulsatile and nonpulsatile impeller pumps the authors established an experimental method for investigating and searching for the hemolysis factors. In this study two pumps with only one differing factor were compared or only one factor on one pump was changed in the middle of the test period. In this way the effect of the individual factor on pump hemolysis could be seen and some factors have been thus confirmed as important reasons for hemolysis: 1) the drift of the pump output (including the volume and efficiency) from the design point; 2) impeller vane angles, i.e., the radial logarithmic spiral angle and the axial helical spiral angle; 3) roughness of vane surface and other blood contacting surfaces of the sealing box and pump housing; 4) vibration of the rotor resulting from dynamic disequilibrium; and 5) prerotation swirl at the inlet of the pump. The blood pressure to be pumped has been shown to have no influence on pump hemolysis. After eliminating the hemolysis factors, the blood trauma of the impeller heart has been reduced remarkably. The index of hemolysis of the nonpulsatile pump is 0.015, about one fifth of a clinically used roller made in Shanghai and two sevenths of one Sarns 7,000 Roller; the index of hemolysis of the pulstile pump is 0.020, about one sixth of a self-made diaphragm pump and one thirteenth of the Polystan pulsa tile pump.

  2. Electrorheological fluid-actuated microfluidic pump

    Science.gov (United States)

    Liu, Liyu; Chen, Xiaoqing; Niu, Xize; Wen, Weijia; Sheng, Ping

    2006-08-01

    The authors report the design and implementation of an electrorheological (ER) fluid-actuated microfluidic pump, with programmable digital control. Our microfluidic pump has a multilayered structure fabricated on polydimethylsiloxane by soft-lithographic technique. The ER microfluidic pump exhibits good performance at high pumping frequencies and uniform liquid flow characteristics. It can be easily integrated with other microfluidic components. The programmable control also gives the device flexibility in its operations.

  3. 76 FR 34192 - Commercial and Industrial Pumps

    Science.gov (United States)

    2011-06-13

    ... Part 431 RIN 1904-AC54 Commercial and Industrial Pumps AGENCY: Office of Energy Efficiency and... commercial and industrial pumps. Additional input and suggestions relevant to this equipment are also welcome... submitting comments. E-mail: Pumps-RFI-2011-STD-0031@ee.doe.gov . Include EERE- 2011-BT-STD-0031 and/or...

  4. 46 CFR 132.120 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Fire pumps. 132.120 Section 132.120 Shipping COAST GUARD....120 Fire pumps. (a) Except as provided by § 132.100(b) of this subpart, each vessel must be equipped with one self-priming power-driven fire pump capable of delivering a single stream of water from...

  5. 46 CFR 169.654 - Bilge pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Bilge pumps. 169.654 Section 169.654 Shipping COAST... Electrical Bilge Systems § 169.654 Bilge pumps. (a) Vessels of less than 65 feet in length must have a portable hand bilge pump having a maximum capacity of 5 gpm. (b) In addition to the requirements...

  6. 76 FR 43218 - Commercial and Industrial Pumps

    Science.gov (United States)

    2011-07-20

    ...; ] DEPARTMENT OF ENERGY 10 CFR Part 431 RIN 1904-AC54 Commercial and Industrial Pumps AGENCY: Department of... efficient product designs for commercial and industrial pumps. The comment period closed on July 13, 2011... commercial and industrial pumps. The comment period is extended to September 16, 2011. DATES: The...

  7. Maternal response to two electric breast pumps

    Science.gov (United States)

    Mechanical characteristics of breast pumps have been shown to influence milk extraction and hormone release in laboratory settings. However, few studies evaluate impact of differences in pump design on long-term breastfeeding success. This study evaluated the impact of a novel pump design on milk ex...

  8. 46 CFR 108.471 - Water pump.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Water pump. 108.471 Section 108.471 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Foam Extinguishing Systems § 108.471 Water pump. Each water pump in a foam...

  9. Properties of Graphene Based Parametric Pump

    Institute of Scientific and Technical Information of China (English)

    LUO Song-Lin; WEI Ya-Dong

    2009-01-01

    The adiabatic parametric electron pump of the infinite zigzag graphene ribbons and the infinite armchair graphene ribbons is investigated by the tight binding method. The pumping signals are added by two gates around the ribbons. It is shown that the dc current can be pumped out by cyclically varying the two gate voltages and the pumped current strongly depends on the driving frequency, the pumping amplitude and the phase difference of the gate voltages. The pumped current is mediated by the graphene energy levels and its peaks occur around the energies where transmission coefficients and density of states are large. The pump current may give one peak or two opposite peaks corresponding to each transmission peak or transmission pair peaks. The height and width of the current peaks increase with the amplitude of the pumping driving voltages. The pumped current is antisymmetric about the phase difference φ=π and for small pumping amplitude the pumped current is a sinusoidal function of the phase difference. Some graphene ribbons, although with different widths, have very similar contours of the transmission coefficients and give the same pumped current figures.

  10. Giant pumps reclaim Chinese coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Kramp, S.

    1987-04-01

    Briefly describes the Fangezhuang Mine disaster in 1984, when miners pierced a wall into a flooded underground cavern, releasing tonnes of water into the pit. The German manufacturer KSB was asked to supply 18 submersible pumps to dewater the flooded workings. The pumps were specially built to handle the aggressive, solid-laden floodwater. The pump design is described. 1 fig.

  11. Wet handling of solids using submersible pumps

    Energy Technology Data Exchange (ETDEWEB)

    Czarnota, Z.; Fahlgren, M.; Grainger, M. [ITT Flygt Slurry Laboratory, Soina (Sweden)

    1996-12-31

    A complete and efficient concept for handling solids in short distance pumping applications is described. The function of pump, mixer, agitator, and sump have been determined in experimental studies. The major factors that affect pump performance such as impeller design and slurry characteristics are discussed. The results apply to a range of applications in industry and mining. 10 refs., 6 figs.

  12. Assessing the energy efficiency of pumps and pump units background and methodology

    CERN Document Server

    Bernd Stoffel, em Dr-Ing

    2015-01-01

    Assessing the Energy Efficiency of Pumps and Pump Units, developed in cooperation with Europump, is the first book available providing the background, methodology, and assessment tools for understanding and calculating energy efficiency for pumps and extended products (pumps+motors+drives). Responding to new EU requirements for pump efficiency, and US DOE exploratory work in setting pump energy efficiency guidelines, this book provides explanation, derivation, and illustration of PA and EPA methods for assessing energy efficiency. It surveys legislation related to pump energy eff

  13. Separating Pumping and Other Influences on Groundwater Head Variation

    Science.gov (United States)

    Shapoori, V.; Western, A. W.; Peterson, T. J.; Costelloe, J.

    2012-12-01

    The dynamics of unconfined groundwater levels are usually the result of numerous and interacting factors, such as land cover change, climate variability and groundwater pumping. Estimating the impact from pumping is highly significant for resource management but also very challenging. A variety of methods are used to model water-table dynamics influenced by pumping, ranging from spatially explicit, numerical models to stochastic approaches. Transfer function noise (TFN) modelling can be used to model the dynamic behaviour of a wide range of hydrologic variables, including time series of groundwater head. Recently, TFN models have been developed to better link water table dynamics with different types of individual stresses, including pumping (Von Asmuth et al. 2002). Peterson & Western (2011) advanced the transfer function noise model of Von Asmuth et al. (2002) to account for non-linear hydrological processes by inclusion of a parsimonious vertically lumped soil moisture storage(SMS). Shapoori et al. (2011) proposed an improved time series formulation for estimation of the impacts of pumping. That study undertook a synthetic assessment of the ability of a range of time series models to represent the impacts of pumping by applying them to groundwater head time series from a synthetic aquifer. This paper further expands the Shapoori at al. (2011) time series method for quantifying the impact of groundwater pumping within unconfined sedimentary aquifers by applying it to real data and by taking account of a surface water body. The study area is the Clydebank groundwater subregion located in Victoria Australia. Nine salinity control pumping bores are used in some of the worst salinity areas to lower the groundwater table and consequently reduce soil salinity. The method has been applied to 43 observation bores and the results show that the model has good predictive performance with mean and minimum coefficient efficiency values of 0.7 and 0.5 respectively. In addition

  14. Pump Application as Hydraulic Turbine – Pump as Turbine (PaT)

    OpenAIRE

    Rusovs, D

    2009-01-01

    The paper considers pump operation as hydraulic turbine with purpose to produce mechanical power from liquid flow. The Francis hydraulic turbine was selected for comparison with centrifugal pump in reverse operation. Turbine and centrifugal pump velocity triangles were considered with purpose to evaluate PaT efficiency. Shape of impeller blades for turbine and pumps was analysed. Specific speed calculation is carried out with purpose to obtain similarity in pump and turbine description. For ...

  15. A simplified heat pump model for use in solar plus heat pump system simulation studies

    OpenAIRE

    Perers, Bengt; Anderssen, Elsa; Nordman, Roger; Kovacs, Peter

    2012-01-01

    Solar plus heat pump systems are often very complex in design, with sometimes special heat pump arrangements and control. Therefore detailed heat pump models can give very slow system simulations and still not so accurate results compared to real heat pump performance in a system. The idea here is to start from a standard measured performance map of test points for a heat pump according to EN 14825 and then determine characteristic parameters for a simplified correlation based model of the he...

  16. Automatic swirl angle measurements for pump intake design

    NARCIS (Netherlands)

    Fockert, A. de; Westende, J.M.C. van 't; Verhaart, F.I.H.

    2014-01-01

    Pre-swirl occurring in pump intake basins influences pump efficiency and lifetime. The exact effect on a pump depends on the pump design. In order to optimize the approach flow towards the pump, physical scale modelling is often applied following the guidelines formulated in pump intake design

  17. Automatic swirl angle measurements for pump intake design

    NARCIS (Netherlands)

    Fockert, A. de; Westende, J.M.C. van 't; Verhaart, F.I.H.

    2014-01-01

    Pre-swirl occurring in pump intake basins influences pump efficiency and lifetime. The exact effect on a pump depends on the pump design. In order to optimize the approach flow towards the pump, physical scale modelling is often applied following the guidelines formulated in pump intake design stand

  18. Optimized ground coupled heat pump mechanical package

    Energy Technology Data Exchange (ETDEWEB)

    Catan, M.A.

    1987-01-01

    This project addresses the question of how well a ground coupled heat pump system could perform with a heat pump which was designed specifically for such systems operating in a northern climate. Conventionally, systems are designed around water source heat pumps which are not designed for ground coupled heat pump application. The objective of the project is to minimize the life cycle cost for a ground coupled system given the freedom to design the heat pump and the ground coil in concert. In order to achieve this objective a number of modeling tools were developed which will likely be of interest in their own right.

  19. Cavitation Effects in Centrifugal Pumps- A Review

    Directory of Open Access Journals (Sweden)

    Maxime Binama

    2016-05-01

    Full Text Available Cavitation is one of the most challenging fluid flow abnormalities leading to detrimental effects on both the centrifugal pump flow behaviors and physical characteristics. Centrifugal pumps’ most low pressure zones are the first cavitation victims, where cavitation manifests itself in form of pitting on the pump internal solid walls, accompanied by noise and vibration, all leading to the pump hydraulic performance degradation. In the present article, a general description of centrifugal pump performance and related parameters is presented. Based on the literature survey, some light were shed on fundamental cavitation features; where different aspects relating to cavitation in centrifugal pumps were briefly discussed

  20. Centrifugal pump inlet pressure site affects measurement.

    Science.gov (United States)

    Augustin, Simon; Horton, Alison; Butt, Warwick; Bennett, Martin; Horton, Stephen

    2010-09-01

    During extracorporeal life support (ECLS), blood is exposed to a myriad of unphysiological factors that can affect outcome. One aspect of this is the sub-atmospheric pressure generated by the ECLS pump and imparted to blood elements along the pump inlet line. This pressure can be measured on the inlet line close to the pump head by adding a connector, or at the venous cannula connection site. We compared the two measurement sites located at both points; between the venous cannula-inlet tubing and inlet tubing-pump, with a range of cannulae and flows. We also investigated the effects on inlet pressure from pump afterload and increasing inlet tubing length.

  1. Altered erythrocyte Na/sup +/ + K/sup +/ pump in adolescent obesity

    Energy Technology Data Exchange (ETDEWEB)

    DeLuise, M.; Rappaport, E.; Flier, J.S.

    1982-11-01

    The number of Na/K pump units and the cation transport activity of the pump were measured in erythrocytes from two etiologically different groups of obese adolescents and a group of normal controls. There was a significant reduction in the number of pump units, as measured by saturation ouabain binding, in erythrocytes from adolescents with idiopathic, early onset obesity. Individuals whose obesity developed subsequent to the appearance of a variety of hypothalamic lesions showed no reduction in the red cell complement of Na/K pump when compared to controls and the cation transport activity of their cells was higher than both the controls and the subjects with idiopathic obesity. These results support data obtained in adults that reduced red cell Na/K pump levels are seen in a group of individuals with idiopathic obesity. They further suggest that such reductions are not likely to be secondary to the obese state per se.

  2. Analysis of heat pumps installed in family housing at Hunter Army Air Field

    Energy Technology Data Exchange (ETDEWEB)

    Parker, S.A.

    1994-08-01

    The US Army Forces Command (FORSCOM) tasked Pacific Northwest Laboratory (PNL) in support of the US Department of Energy (DOE) Federal Energy Management Program (FEMP) to conduct a postconstruction evaluation of the air-source heat pumps installed in family housing at Hunter Army Air Field (AAF). The objective of this project was to investigate and resolve concerns about an increase in energy costs at Hunter AAF following the installation of heat pumps in November 1992. After completing several analyses and a field inspection of the heat pumps in family housing at Hunter AAF, the following conclusions were made: the installation of air-source heat pumps reduced the annual energy cost in family housing by $46,672 in 1993; the heat pump thermostat controls in Hunter AAF family housing appear to be incorrectly installed; and the Hunter AAF electric utility bill increased 10% during the first 6 months of 1993 compared to the first 6 months of 1992.

  3. Mosquitoes drink with a burst in reserve: explaining pumping behavior with a fluid mechanics model

    Science.gov (United States)

    Chatterjee, Souvick; Socha, Jake; Stremler, Mark

    2014-11-01

    Mosquitoes drink using a pair of in-line pumps in the head that draw liquid food through the proboscis. Experimental observations with synchrotron x-ray imaging indicate two modes of drinking: a predominantly occurring continuous mode, in which the cibarial and pharyngeal pumps expand cyclically at a constant phase difference, and an occasional, isolated burst mode, in which the pharyngeal pump expansion is 10 to 30 times larger than in the continuous mode. We have used a reduced order model of the fluid mechanics to hypothesize an explanation of this variation in drinking behavior. Our model results show that the continuous mode is more energetically efficient, whereas the burst mode creates a large pressure drop across the proboscis, which could potentially be used to clear blockages. Comparisons with pump knock-out configurations demonstrate different functional roles of the pumps in mosquito feeding. This material is based upon work supported by the NSF under Grant No. #0938047.

  4. Ultra low-energy switch based on a cavity soliton laser with pump modulation

    Science.gov (United States)

    Eslami, M.; Gandomani, S. Z.; Prati, F.; Tajalli, H.; Kheradmand, R.

    2017-01-01

    We study the effects of pump modulation in a cavity soliton laser consisting of a vertical cavity surface emitting laser with an intra-cavity saturable absorber. We show that a drifting soliton experiences enhanced mobility features by modulating the pump at the resonance frequency, and the effects are even larger below resonance. In particular, pump modulation reduces the rest time of the soliton in the initial stage of the motion and it increases its drift velocity in this regime. Moreover, pump modulation allows a decrease in the switching energy of the soliton to an amount equal to 36 photons. These results indicate that pump modulation is a promising way for the use of a cavity soliton laser as a fast optical buffer and an ultra low-energy optical switch.

  5. [Temporary use of centrifugal pump for pump thrombosis in patients with paracorporeal ventricular assist device].

    Science.gov (United States)

    Kimura, Mitsutoshi; Kinoshita, Osamu; Nawata, Kan; Yamauchi, Haruo; Itoda, Yoshifumi; Hoshino, Yasuhiro; Kashiwa, Koichi; Kubo, Hitoshi; Kurosawa, Hideo; Takahashi, Mai; Koga, Sayaka; Ono, Minoru

    2015-05-01

    Nipro paracorporeal ventricular assist device( VAD) is often associated with pump thrombosis which causes severe complications such as brain infarction, often requiring pump change. However, Nipro VAD pump is an expensive device and it is difficult to change pumps frequently at a short interval. We have temporarily used Rotaflow centrifugal pump for recurrent pump thrombosis in patients with Nipro VADs. From January 2012 through December 2013, 19 patients underwent Nipro VADs implantation at our institution, and 9 of them underwent pump change from Nipro pumps to Rotaflow centrifugal pumps. A total of 25 Rotaflow centrifugal pumps were used in these 9 patients, with the total circulatory support duration of 526 days. The median support period was 15 days (range;2-128 days). There were 2 cerebrovascular accidents and 1 Rotaflow pump circuit thrombosis during this period. Change from Rotaflow to Nipro VAD pump resulted in decrease in hematocrit by about 3 point. There was no difference in liver or renal function between before and after the pump change. Our results suggest that temporary use of Rotaflow centrifugal pump for recurrent pump thrombosis in patients with Nipro VADs may be a promising alternative.

  6. Experimental Study on Series Operation of Sliding Vane Pump and Centrifugal Pump

    Directory of Open Access Journals (Sweden)

    Tao Li

    2013-01-01

    Full Text Available A platform for sliding vane pump and centrifugal pump tests is installed to study the series operation of them under different characteristics of pipeline. Firstly, the sliding vane pump and the centrifugal pump work independently, and the performance is recorded. Then, the two types of pumps are combined together, with the sliding vane pump acting as the feeding pump. Comparison is made between the performance of the independently working pump and the performance of series operation pump. Results show that the system flow rate is determined by the sliding vane pump. In order to ensure the stability of the series operation pumping system, the energy consumption required by the pipeline under the system flow should be greater than the pressure energy centrifugal pump can generate. Otherwise, the centrifugal pump can not operate stably, with reflux, swirl, gas-liquid two-phase flow in the runner and strong vibration and noise. The sliding vane pump can be in serial operation with the centrifugal pump under limited conditions.

  7. The pumping of hydrogen and helium by sputter-ion pumps

    Energy Technology Data Exchange (ETDEWEB)

    Welch, K.M.; Pate, D.J.; Todd, R.J.

    1992-01-01

    The pumping of hydrogen in diode and triode sputter-ion pumps is discussed. The type of cathode material used in these pumps is shown to have a significant impact on the effectiveness with which hydrogen is pumped. Examples of this include data for pumps with aluminum and titanium-alloy cathodes. Diode pumps with aluminum cathodes are shown to be no more effective in the pumping of hydrogen than in the pumping of helium. The use of titanium or titanium alloy anodes is also shown to measurably impact on the speed of these pumps at.very low pressures. This stems from the fact that hydrogen is [times]10[sup 6] more soluble in titanium than in stainless steel. Hydrogen becomes resident in the anodes because of fast neutral burial. Lastly, quantitative data are given for the He speeds and capacities of both noble and conventional diode and triode pumps. The effectiveness of various pump regeneration procedures, subsequent to the pumping of He, is reported.These included bakeout and N[sub 2] glow discharge cleaning. The comparative desorption of He with the subsequent pumping of N[sub 2] is reported on. The N[sub 2] speed of these pumps was used as the benchmark for defining the size of the pumps vs. their respective He speeds.

  8. The pumping of hydrogen and helium by sputter-ion pumps. Revision 3/93

    Energy Technology Data Exchange (ETDEWEB)

    Welch, K.M.; Pate, D.J.; Todd, R.J.

    1992-12-31

    The pumping of hydrogen in diode and triode sputter-ion pumps is discussed. The type of cathode material used in these pumps is shown to have a significant impact on the effectiveness with which hydrogen is pumped. Examples of this include data for pumps with aluminum and titanium-alloy cathodes. Diode pumps with aluminum cathodes are shown to be no more effective in the pumping of hydrogen than in the pumping of helium. The use of titanium or titanium alloy anodes is also shown to measurably impact on the speed of these pumps at.very low pressures. This stems from the fact that hydrogen is {times}10{sup 6} more soluble in titanium than in stainless steel. Hydrogen becomes resident in the anodes because of fast neutral burial. Lastly, quantitative data are given for the He speeds and capacities of both noble and conventional diode and triode pumps. The effectiveness of various pump regeneration procedures, subsequent to the pumping of He, is reported.These included bakeout and N{sub 2} glow discharge cleaning. The comparative desorption of He with the subsequent pumping of N{sub 2} is reported on. The N{sub 2} speed of these pumps was used as the benchmark for defining the size of the pumps vs. their respective He speeds.

  9. Velocity selective optical pumping resonance sign reversal

    Science.gov (United States)

    Krasteva, A.; Slavov, D.; Todorov, G.; Cartaleva, S.

    2013-03-01

    We report experimental and theoretical examinations of the peculiarities in Velocity Selective Optical Pumping (VSOP) resonance behavior at open and closed hyperfine transition spectra of Cs atoms (on the D2 line), confined in optical cell with thickness L = 6λ, where λ = 852 nm. For linear and circular polarizations of the irradiating light, open transitions exhibit reduced absorption (fluorescence) VSOP resonances whose contrast increases with atomic concentration and light intensity. However, in case of closed transition the situation is different, the enhanced absorption (fluorescence) VSOP resonance reverses its sign with the atomic concentration and light intensity. Theoretical analysis based on the density matrix formalism, taking into account the statistical tensors describing atomic population and longitudinal alignment, shows that the VSOP resonance sign reversal at the closed transition can be attributed to the efficiency reduction of population transfer by the spontaneous decay with atomic source temperature.

  10. Engine lubrication circuit including two pumps

    Science.gov (United States)

    Lane, William H.

    2006-10-03

    A lubrication pump coupled to the engine is sized such that the it can supply the engine with a predetermined flow volume as soon as the engine reaches a peak torque engine speed. In engines that operate predominately at speeds above the peak torque engine speed, the lubrication pump is often producing lubrication fluid in excess of the predetermined flow volume that is bypassed back to a lubrication fluid source. This arguably results in wasted power. In order to more efficiently lubricate an engine, a lubrication circuit includes a lubrication pump and a variable delivery pump. The lubrication pump is operably coupled to the engine, and the variable delivery pump is in communication with a pump output controller that is operable to vary a lubrication fluid output from the variable delivery pump as a function of at least one of engine speed and lubrication flow volume or system pressure. Thus, the lubrication pump can be sized to produce the predetermined flow volume at a speed range at which the engine predominately operates while the variable delivery pump can supplement lubrication fluid delivery from the lubrication pump at engine speeds below the predominant engine speed range.

  11. Geothermal Heat Pump Benchmarking Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-01-17

    A benchmarking study was conducted on behalf of the Department of Energy to determine the critical factors in successful utility geothermal heat pump programs. A Successful program is one that has achieved significant market penetration. Successfully marketing geothermal heat pumps has presented some major challenges to the utility industry. However, select utilities have developed programs that generate significant GHP sales. This benchmarking study concludes that there are three factors critical to the success of utility GHP marking programs: (1) Top management marketing commitment; (2) An understanding of the fundamentals of marketing and business development; and (3) An aggressive competitive posture. To generate significant GHP sales, competitive market forces must by used. However, because utilities have functioned only in a regulated arena, these companies and their leaders are unschooled in competitive business practices. Therefore, a lack of experience coupled with an intrinsically non-competitive culture yields an industry environment that impedes the generation of significant GHP sales in many, but not all, utilities.

  12. Four-Pass Coupler for Laser-Diode-Pumped Solid-State Laser

    Science.gov (United States)

    Coyle, Donald B.

    2008-01-01

    A four-pass optical coupler affords increased (in comparison with related prior two-pass optical couplers) utilization of light generated by a laser diode in side pumping of a solid-state laser slab. The original application for which this coupler was conceived involves a neodymium-doped yttrium aluminum garnet (Nd:YAG) crystal slab, which, when pumped by a row of laser diodes at a wavelength of 809 nm, lases at a wavelength of 1,064 nm. Heretofore, typically, a thin laser slab has been pumped in two passes, the second pass occurring by virtue of reflection of pump light from a highly reflective thin film on the side opposite the side through which the pump light enters. In two-pass pumping, a Nd:YAG slab having a thickness of 2 mm (which is typical) absorbs about 84 percent of the 809-nm pump light power, leaving about 16 percent of the pump light power to travel back toward the laser diodes. This unused power can cause localized heating of the laser diodes, thereby reducing their lifetimes. Moreover, if the slab is thinner than 2 mm, then even more unused power travels back toward the laser diodes. The four-pass optical coupler captures most of this unused pump light and sends it back to the laser slab for two more passes. As a result, the slab absorbs more pump light, as though it were twice as thick. The gain and laser cavity beam quality of a smaller laser slab in conjunction with this optical coupler can thus be made comparable to those of a larger two-pass-pumped laser slab.

  13. Analysis of frequency dependent pump light absorption

    Science.gov (United States)

    Wohlmuth, Matthias; Pflaum, Christoph

    2011-03-01

    Simulations have to accurately model thermal lensing in order to help improving resonator design of diode pumped solid state lasers. To this end, a precise description of the pump light absorption is an important prerequisite. In this paper, we discuss the frequency dependency of the pump light absorption in the laser crystal and its influence on the simulated laser performance. The results show that the pump light absorption has to include the spectral overlap of the emitting pump source and the absorbing laser material. This information can either be used for a fully frequency dependent absorption model or, at least in the shown examples, to compute an effective value for an exponential Beer-Lambert law of absorption. This is particularly significant at pump wavelengths coinciding with a peak of absorption. Consequences for laser stability and performance are analyzed for different pump wavelengths in a Nd:YAG laser.

  14. Topological Thouless pumping of ultracold fermions

    Science.gov (United States)

    Nakajima, Shuta; Tomita, Takafumi; Taie, Shintaro; Ichinose, Tomohiro; Ozawa, Hideki; Wang, Lei; Troyer, Matthias; Takahashi, Yoshiro

    2016-04-01

    An electron gas in a one-dimensional periodic potential can be transported even in the absence of a voltage bias if the potential is slowly and periodically modulated in time. Remarkably, the transferred charge per cycle is sensitive only to the topology of the path in parameter space. Although this so-called Thouless charge pump was first proposed more than thirty years ago, it has not yet been realized. Here we report the demonstration of topological Thouless pumping using ultracold fermionic atoms in a dynamically controlled optical superlattice. We observe a shift of the atomic cloud as a result of pumping, and extract the topological invariance of the pumping process from this shift. We demonstrate the topological nature of the Thouless pump by varying the topology of the pumping path and verify that the topological pump indeed works in the quantum regime by varying the speed and temperature.

  15. Magnetopumping current in graphene Corbino pump

    Science.gov (United States)

    Abdollahipour, Babak; Moomivand, Elham

    2017-02-01

    We study conductance and adiabatic pumped charge and spin currents in a graphene quantum pump with Corbino geometry in the presence of an applied perpendicular magnetic field. Pump is driven by the periodic and out of phase modulations of the magnetic field and an electrostatic potential applied to the ring area of the pump. We show that Zeeman splitting, despite its smallness, suppresses conductance and pumped current oscillations at zero doping. Moreover, quite considerable spin conductance and pumped spin current are generated at low dopings due to Zeeman splitting. We find that pumped charge and spin currents increase by increasing the magnetic field, with small oscillations, until they are suppressed due to the effect of nonzero doping and Zeeman splitting.

  16. Optimum shapes for pump limiters

    Energy Technology Data Exchange (ETDEWEB)

    Ulrickson, M.

    1982-05-01

    The design of a pump limiter depends strongly on the details of the plasma scrapeoff zone. A model has been developed which allows the transport coefficients in the scrapeoff to be functions of n and t. This model has been used to predict scrapeoff profiles for FED/INTOR. The profiles are used to find and analyze limiter profiles. The results suggest the use of limiter shapes which curve toward the plasma.

  17. Actively Pumped Faraday Optical Filter

    Science.gov (United States)

    1996-04-30

    Richard I. Billmers Vincent M. Contarino David M. Allocca Martin F. Squicciarini William J. Scharpf 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...States Patent [i9] Billmers et al. iiiiiiifflimi iilliiiiiii US005513032A [ii] Patent Number: [45] Date of Patent: 5,513,032 Apr. 30, 1996...54] ACTIVELY PUMPED FARADAY OPTICAL FILTER [75] Inventors: Richard I. Billmers , Bensalem; Vincent M. Contarino, Warrington; David M

  18. Modelling and simulation of a dual-clutch transmission vehicle to analyse the effect of pump selection on fuel economy

    Science.gov (United States)

    Ahlawat, R.; Fathy, H. K.; Lee, B.; Stein, J. L.; Jung, D.

    2010-07-01

    Positive displacement pumps are used in automotive transmissions to provide pressurised fluid to various hydraulic components in the transmission and also lubricate the mechanical components. The output flow of these pumps increases with pump/transmission speed, almost linearly, but the transmission flow requirements often saturate at higher speeds, resulting in excess flow capacity that must be wasted by allowing it to drain back to the sump. This represents a parasitic loss in the transmission leading to a loss in fuel economy. To overcome this issue, variable displacement pumps have been used in the transmission, where the output flow can be reduced by controlling the displacement of the pump. The use of these pumps in automatic transmissions has resulted in better fuel economy as compared with some types of fixed displacement pumps. However, the literature does not fully explore the benefits of variable displacement pumps to a specific type of transmission namely, dual-clutch transmission (DCT), which has different pressure and flow requirements from an epicyclic gear train. This paper presents an analysis of the effect of pump selection on fuel economy in a five-speed DCT of a commercial vehicle. Models of the engine, transmission, and vehicle are developed along with the models of two different types of pumps: a fixed displacement gerotor pump and a variable displacement vane pump. The models are then parameterised using experimental data, and the fuel economy of the vehicle is simulated on a standard driving cycle. The results suggest that the fuel economy benefit obtained by the use of the variable displacement pump in DCTs is comparable to the benefit previously shown for these pumps in automatic transmissions.

  19. Charge-pump voltage converter

    Science.gov (United States)

    Brainard, John P.; Christenson, Todd R.

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  20. Sorption Refrigeration / Heat Pump Cycles

    Science.gov (United States)

    Saha, Bidyut Baran; Alam, K. C. Amanul; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    Over the past few decades there have been considerable efforts to use adsorption (solid/vapor) for cooling and heat pump applications, but intensified efforts were initiated only since the imposition of international restrictions on the production and use of CFCs (chlorofluorocarbons) and HCFCs (hydrochlorofluorocarbons). Up to now, only the desiccant evaporative cooling system of the open type has achieved commercial use, predominantly in the United States. Closed-type adsorption refrigeration and heat pump systems are rarely seen in the market, or are still in the laboratory testing stage. Promising recent development have been made in Japan for the use of porous metal hydrides and composite adsorbents. In this paper, a short description of adsorption theories along with an overview of present status and future development trends of thermally powered adsorption refrigeration cycles are outlined putting emphasis on experimental achievements. This paper also addressed some advanced absorption cycles having relatively higher COP, and also summarizes fundamental concepts of GAX cycles and various GAX cycles developed for heat pump applications.

  1. Hemolysis generation from a novel, linear positive displacement blood pump for cardiopulmonary bypass on a six kilogram piglet: a preliminary report.

    Science.gov (United States)

    Lawson, D Scott; Eilers, Derek; Osorio Lujan, Suzanne; Bortot, Maria; Jaggers, James

    2017-05-01

    Current blood pumps used for cardiopulmonary bypass generally fall into two different pump design categories; non-occlusive centrifugal pumps and occlusive, positive-displacement roller pumps. The amount of foreign surface area of extracorporeal circuits correlates with post-operative morbidity due to systemic inflammation, leading to a push for technology that reduces the amount of foreign surfaces. Current roller pumps are bulky and the tubing forms an arc in the pumping chamber (raceway), positioning the inlet 360 degrees from the outlet, making it very difficult to place the pump closer to the patient and to efficiently reduce tubing length. These challenges put existing roller pumps at a disadvantage for use in a compact cardiopulmonary bypass circuit. Centrifugal blood pumps are easier to incorporate into miniature circuit designs. However, the prime volumes of current centrifugal pump designs are large, especially for pediatric extracorporeal circuits where the prime volumes are too great to be of clinical value. We describe a preliminary report on a novel, occlusive, linear, single-helix, positive-displacement blood pump which allows for decreased prime volume and surface area of the extracorporeal circuit. This new experimental pump design was used to perfuse a 6 kilogram piglet with a pediatric cardiopulmonary bypass circuit for two hours of continuous use. Blood samples were obtained every thirty minutes and assayed for plasma free hemolysis generation. The results from this initial experiment showed low plasma free hemoglobin generation and encourages the authors to further develop this concept.

  2. Millwater Pumping System Optimization Improves Efficiency and Saves Energy at an Automotive Glass Plant

    Energy Technology Data Exchange (ETDEWEB)

    None

    2003-03-01

    In 2001, the Visteon automotive glass plant in Nashville, Tennessee renovated its millwater pumping system. This improvement saved the plant $280,000 annually in energy and operating costs, reduced annual energy consumption by 3.2 million kilowatt-hours, reduced water consumption, improved system performance, and reduced use of water treatment chemicals.

  3. Flow dynamical behavior and performance of a micro viscous pump with unequal inlet and outlet areas

    Directory of Open Access Journals (Sweden)

    Chenhui Hu

    2016-01-01

    Full Text Available The micro viscous pump is an important type of fluidic device. Optimizing the working performance of the pump is crucial for its wider application. A micro viscous pump design with unequal inlet and outlet areas is proposed in this paper. The flow field of the viscous pump is investigated using 2D laminar simulations. The mass flow rate and driving power are studied with different opening angles. The effects of the Reynolds number and the pressure load on the working performance are discussed in detail. Flow structures and vortex evolution are analyzed. With larger inlet and outlet areas, a higher mass flow rate is obtained and less driving power is achieved. A high pressure load results in a reduction in mass flow rate and an increase in driving power. Pumps with large opening angles are more susceptive to the Reynolds number and the pressure load. The adverse impact of the pressure load can be reduced by increasing the rotor speed. The vortex structure is affected by the geometric and operating parameters in the flow field. The flow dynamical behavior of the viscous pump exerts significant influence on its pumping ability. The present work gives rise to performance improvements for the micro viscous pump.

  4. Roller and Centrifugal Pumps: A Retrospective Comparison of Bleeding Complications in Extracorporeal Membrane Oxygenation.

    Science.gov (United States)

    Halaweish, Ihab; Cole, Adam; Cooley, Elaine; Lynch, William R; Haft, Jonathan W

    2015-01-01

    Centrifugal pumps are increasingly used for extracorporeal membrane oxygenation (ECMO) rather than roller pumps. However, shear forces induced by these types of continuousflow pumps are associated with acquired von Willebrand factor deficiency and bleeding complications. This study was undertaken to compare adverse bleeding complications with the use of centrifugal and roller pumps in patients on prolonged ECMO support. The records of all adult ECMO patients from June 2002 to 2013 were retrospectively reviewed using the University of Michigan Health System database and the Extracorporeal Life Support Organization registry, focusing on patients supported for at least 5 days. Ninety-five ECMO patients met criteria for inclusion (48 roller vs. 47 centrifugal pump). Indications included pulmonary (79%), cardiac (15%), and extracorporeal cardiopulmonary resuscitation (6%), without significant difference between the two groups. Despite lower heparin anticoagulation (10.9 vs. 13.7 IU/kg/hr) with centrifugal pumps, there was a higher incidence of nonsurgical bleeding (gastrointestinal, pulmonary, and neurological) in centrifugal pump patients (26.1 vs. 9.0 events/1,000 patient-days, p = 0.024). In conclusion, in our historical comparison, despite reduced anticoagulation, ECMO support using centrifugal pumps was associated with a higher incidence of nonsurgical bleeding. The mechanisms behind this are multifactorial and require further investigation.

  5. A sliding mode-based starling-like controller for implantable rotary blood pumps.

    Science.gov (United States)

    Bakouri, Mohsen A; Salamonsen, Robert F; Savkin, Andrey V; AlOmari, Abdul-Hakeem H; Lim, Einly; Lovell, Nigel H

    2014-07-01

    Clinically adequate implementation of physiological control of a rotary left ventricular assist device requires a sophisticated technique such as the recently proposed method based on the Frank-Starling mechanism. In this mechanism, the stroke volume of the heart increases in response to an increase in the volume of blood filling the left ventricle at the end of diastole. To emulate this process, changes in pump speed need to automatically regulate pump flow to ensure that the combined output of the left ventricle and pump match the output of the right ventricle across changing cardiovascular states. In this approach, we exploit the linear relationship between estimated mean pump flow (Q ̅ est) and pump flow pulsatility (PIQp) in a tracking control algorithm based on sliding mode control. The immediate response of the controller was assessed using a lumped parameter model of the cardiovascular system (CVS) and pump from which could be extracted both Q ̅ est and PIQp. Two different perturbations from the resting state in the presence of left ventricular failure were tested. The first was blood loss requiring a reduction in pump flow to match the reduced output from the right ventricle and to avoid the complication of ventricular suction. The second was exercise, requiring an increase in pump flow. The sliding mode controller induced the required changes in Qp within approximately five heart beats in the blood loss simulation and eight heart beats in the exercise simulation without clinically significant transients or steady-state errors.

  6. In vivo assessment of a new method of pulsatile perfusion based on a centrifugal pump.

    Science.gov (United States)

    Herreros, Jesús; Ubilla, Matías; Berjano, Enrique J; Vila-Nuñez, Juan E; Páramo, José A; Sola, Josu; Mercé, Salvador

    2010-02-01

    The aim of this study was to assess platelet dysfunction and damage to organs after extracorporeal circulation using a pump based on a new method that adds a pulsatile flow to the continuous flow provided by a centrifugal pump. The continuous component of the total flow (2-3 L/min) is created by a Bio-Pump centrifugal pump, while the pulsatile component is created by the pulsating of an inner membrane pneumatically controlled by an intra-aortic counterpulsation balloon console (systolic volume of 37.5 mL in an asynchronous way with a frequency of 60 bpm). Six pigs were subjected to a partial cardiopulmonary bypass lasting 180 min and were sacrificed 60 min after extracorporeal circulation was suspended. The hematological study included the measurement of hematocrit, hemoglobin, leukocytes, and platelet function. The new pump did not significantly alter either platelet count or platelet function. In contrast, hematocrit and hemoglobin were significantly reduced during extracorporeal circulation (approximately 5% P = 0.011, and 2 g/dL P = 0.01, respectively). The leukocyte count during extracorporeal circulation showed a tendency to decrease, but this was not significant. In general, the short-term use of the new pump (4 h) did not cause any serious morphological damage to the heart, lung, kidney, or liver. The results suggest that the hemodynamic performance of the new pump is similar to a conventional centrifugal pump and could therefore be appropriate for use in extracorporeal circulation.

  7. Nanoparticles as Efflux Pump and Biofilm Inhibitor to Rejuvenate Bactericidal Effect of Conventional Antibiotics

    Science.gov (United States)

    Gupta, Divya; Singh, Ajeet; Khan, Asad U.

    2017-07-01

    The universal problem of bacterial resistance to antibiotic reflects a serious threat for physicians to control infections. Evolution in bacteria results in the development of various complex resistance mechanisms to neutralize the bactericidal effect of antibiotics, like drug amelioration, target modification, membrane permeability reduction, and drug extrusion through efflux pumps. Efflux pumps acquire a wide range of substrate specificity and also the tremendous efficacy for drug molecule extrusion outside bacterial cells. Hindrance in the functioning of efflux pumps may rejuvenate the bactericidal effect of conventional antibiotics. Efflux pumps also play an important role in the exclusion or inclusion of quorum-sensing biomolecules responsible for biofilm formation in bacterial cells. This transit movement of quorum-sensing biomolecules inside or outside the bacterial cells may get interrupted by impeding the functioning of efflux pumps. Metallic nanoparticles represent a potential candidate to block efflux pumps of bacterial cells. The application of nanoparticles as efflux pump inhibitors will not only help to revive the bactericidal effect of conventional antibiotics but will also assist to reduce biofilm-forming capacity of microbes. This review focuses on a novel and fascinating application of metallic nanoparticles in synergy with conventional antibiotics for efflux pump inhibition.

  8. Damages on pumps and systems the handbook for the operation of centrifugal pumps

    CERN Document Server

    Merkle, Thomas

    2014-01-01

    Damage on Pumps and Systems. The Handbook for the Operation of Centrifugal Pumps offers a combination of the theoretical basics and practical experience for the operation of circulation pumps in the engineering industry. Centrifugal pumps and systems are extremely vulnerable to damage from a variety of causes, but the resulting breakdown can be prevented by ensuring that these pumps and systems are operated properly. This book provides a total overview of operating centrifugal pumps, including condition monitoring, preventive maintenance, life cycle costs, energy savings and economic aspects. Extra emphasis is given to the potential damage to these pumps and systems, and what can be done to prevent breakdown. Addresses specific issues about pumping of metal chips, sand, abrasive dust and other solids in fluidsEmphasis on economic and efficiency aspects of predictive maintenance and condition monitoring Uses life cycle costs (LCC) to evaluate and calculate the costs of pumping systems

  9. An economic evaluation comparison of solar water pumping system with engine pumping system for rice cultivation

    Science.gov (United States)

    Treephak, Kasem; Thongpron, Jutturit; Somsak, Dhirasak; Saelao, Jeerawan; Patcharaprakiti, Nopporn

    2015-08-01

    In this paper we propose the design and economic evaluation of the water pumping systems for rice cultivation using solar energy, gasoline fuel and compare both systems. The design of the water and gasoline engine pumping system were evaluated. The gasoline fuel cost used in rice cultivation in an area of 1.6 acres. Under same conditions of water pumping system is replaced by the photovoltaic system which is composed of a solar panel, a converter and an electric motor pump which is compose of a direct current (DC) motor or an alternating current (AC) motor with an inverter. In addition, the battery is installed to increase the efficiency and productivity of rice cultivation. In order to verify, the simulation and economic evaluation of the storage energy battery system with batteries and without batteries are carried out. Finally the cost of four solar pumping systems was evaluated and compared with that of the gasoline pump. The results showed that the solar pumping system can be used to replace the gasoline water pumping system and DC solar pump has a payback less than 10 years. The systems that can payback the fastest is the DC solar pumping system without batteries storage system. The system the can payback the slowest is AC solar pumping system with batteries storage system. However, VAC motor pump of 220 V can be more easily maintained than the motor pump of 24 VDC and batteries back up system can supply a more stable power to the pump system.

  10. Irregularities in Pump-Induced Tilt Above Shallow Aquifers

    Science.gov (United States)

    Kuempel, H. J.; Fabian, M.

    2003-12-01

    Near surface ground tilt induced by the extraction of fluids from subsurface reservoirs has repeatedly been used to constrain reservoir parameters. In general, pump-induced tilt is found to be proportional in strength to the pore pressure gradient created by the pumping, to be a function of poroelastic rock parameters, and to depend on the geometric configuration of the tilt sensor and the productive sections of a well. Assuming radial flow, the strike of the tilt signal should point toward the productive well. However, inversion of near surface tilt can be hampered through irregularities in the pump-induced signal and suffer from insufficient knowledge of the influence of heterogeneities in the subsoil, either within or above the reservoir. We can learn more about the impact of such heterogeneities and reduce ambiguities by analyzing case studies. New observational data from 3 test sites in Germany confirm that a variety of causes can produce irregularities in pump-induced surface deformation, namely: (1) The strike of a tilt signal can considerably deviate from the direction toward the active well. A reason could be that the steepest effective pore pressure gradient builds up in another than radial direction (thereby generating anisotropic fluid flow). Accordingly, tilt hodographs for a complete pump cycle may be elliptic rather than follow a line. (2) The normal rule of how the signal strength depends on the horizontal and the vertical distance may be violated. Structural heterogeneities in the subsurface are the most likely cause for this behaviour. (3) Recovery of the induced tilt signal following the cessation of pumping can be incomplete. This could indicate a non-reversible compaction possibly due to overexploitation of a reservoir. (4) A transient sign reversal of ground tilt may occur during the build-up phase of the signal. This feature could be an analogue to the so-called Noordbergum effect occasionally seen in the response of well levels at locations

  11. Analyzing atmospheric kinetic pathways using PumpKin

    Science.gov (United States)

    Markosyan, A. H.; Luque, A.; Gordillo-Vázquez, F. J.; Ebert, U.

    2013-09-01

    In the present work we show the application of our software tool called PumpKin (pathway reduction method for plasma kinetic models) to find all principal pathways of atmospheric kinetic system, i.e. the dominant reaction sequences, in chemical reaction systems. The goal was to reduce a complex plasma chemistry model. Recent kinetic models of atmospheric chemistry, or any industrial application, contain thousands of chemical reactions and species. The main difficulty is that these reduced chemical pathways depend on timescales, electric field, temperature, pressure etc. PumpKin is a universal tool, which only requires from user the temporal profile of the densities of species and the reaction rates, as well the stoichiometric matrix of the system. Also, the user should specify the timescale of interest.

  12. Hemocompatibility of a hydrodynamic levitation centrifugal blood pump.

    Science.gov (United States)

    Yamane, Takashi; Maruyama, Osamu; Nishida, Masahiro; Kosaka, Ryo; Sugiyama, Daisuke; Miyamoto, Yusuke; Kawamura, Hiroshi; Kato, Takahisa; Sano, Takeshi; Okubo, Takeshi; Sankai, Yoshiyuki; Shigeta, Osamu; Tsutsui, Tatsuo

    2007-01-01

    A noncontact type centrifugal pump without any complicated control or sensing modules has been developed as a long-term implantable artificial heart. Centrifugal pumps with impellers levitated by original hydrodynamic bearings were designed and have been modified through numerical analyses and in vitro tests. The hemolysis level was reduced by changing the pressure distribution around the impeller and subsequently expanding the bearing gap. Thrombus formation in the bearing was examined with in vitro thrombogenesis tests and was reduced by changing the groove shapes to increase the bearing-gap flow to 3% of the external flow. Unnecessary vortices around the vanes were also eliminated by changing the number of vanes from four to six.

  13. Paper pump for passive and programmable transport.

    Science.gov (United States)

    Wang, Xiao; Hagen, Joshua A; Papautsky, Ian

    2013-01-01

    In microfluidic systems, a pump for fluid-driving is often necessary. To keep the size of microfluidic systems small, a pump that is small in size, light-weight and needs no external power source is advantageous. In this work, we present a passive, simple, ultra-low-cost, and easily controlled pumping method based on capillary action of paper that pumps fluid through conventional polymer-based microfluidic channels with steady flow rate. By using inexpensive cutting tools, paper can be shaped and placed at the outlet port of a conventional microfluidic channel, providing a wide range of pumping rates. A theoretical model was developed to describe the pumping mechanism and aid in the design of paper pumps. As we show, paper pumps can provide steady flow rates from 0.3 μl/s to 1.7 μl/s and can be cascaded to achieve programmable flow-rate tuning during the pumping process. We also successfully demonstrate transport of the most common biofluids (urine, serum, and blood). With these capabilities, the paper pump has the potential to become a powerful fluid-driving approach that will benefit the fielding of microfluidic systems for point-of-care applications.

  14. Characterization and reduction of flow separation in jet pumps for laminar oscillatory flows

    CERN Document Server

    Timmer, Michael A G; Bühler, Simon; Wilcox, Douglas; van der Meer, Theo H

    2016-01-01

    A computational fluid dynamics model is used to predict the oscillatory flow through tapered cylindrical tube sections (jet pumps). The asymmetric shape of jet pumps results in a time-averaged pressure drop that can be used to suppress Gedeon streaming in closed-loop thermoacoustic devices. However, previous work has shown that flow separation in the diverging flow direction counteracts the time-averaged pressure drop. In this work, the characteristics of flow separation in jet pumps are identified and coupled with the observed jet pump performance. Furthermore, it is shown that the onset of flow separation can be shifted to larger displacement amplitudes by designs that have a smoother transition between the small opening and the tapered surface of the jet pump. These design alterations also reduce the duration of separated flow, resulting in more effective and robust jet pumps. To make the proposed jet pump designs more compact without reducing their performance, the minimum big opening radius that can be i...

  15. Investigation on the influence of jetting equipment on the characteristics of centrifugal pump

    Directory of Open Access Journals (Sweden)

    Qiaorui Si

    2016-08-01

    Full Text Available To reduce radial noises from the motor of centrifugal pumps, this study designed a water cooling system called jetting equipment to replace traditional fan cooling systems in pump motors. By measuring radiated noises, head, efficiency, and cavitation performance, the research compared the differences among experimental results of the original pump unit, the one with a normal design jetting pipe and another one with a larger jetting pipe. Results show that the radiated sound pressure level of the model pump was significantly reduced by 8.3 dB after integrating the jetting pipe. With a normal jetting pipe, no significant changes were observed in the head, efficiency, and shaft power curves, and cavitation performance improved under small flow rate. However, the performance with the larger jetting pipe worsened, except the hump phenomenon of the model pump under a small flow rate was enhanced. Computational fluid dynamics method was used to calculate the internal flow of three model pumps in order to investigate the jetting flow effect. A comparison among the flow fields at the inlet of the three types of pumps indicated that high-pressure water injection can effectively control inlet recirculation and improve velocity distribution in the inlet flow field with decreased recirculation vortex strength and recirculation onset critical flow rate.

  16. Combining pump-and-treat and physical barriers for contaminant plume control.

    Science.gov (United States)

    Bayer, Peter; Finkel, Michael; Teutsch, Georg

    2004-01-01

    A detailed analysis is presented of the hydraulic efficiency of plume management alternatives that combine a conventional pump-and-treat system with vertical, physical hydraulic barriers such as slurry walls or sheet piles. Various design settings are examined for their potential to reduce the pumping rate needed to obtain a complete capture of a given contaminated area. Using established modeling techniques for flow and transport, those barrier configurations (specified by location, shape, and length) that yield a maximum reduction of the pumping rate are identified assuming homogeneous aquifer conditions. Selected configurations are further analyzed concerning their hydraulic performance under heterogeneous aquifer conditions by means of a stochastic approach (Monte Carlo simulations) with aquifer transmissivity as a random space function. The results show that physical barriers are an appropriate means to decrease expected (mean) pumping rates, as well as the variance of the corresponding pumping rate distribution at any given degree of heterogeneity. The methodology presented can be transferred easily to other aquifer scenarios, provided some basic premises are fulfilled, and may serve as a basis for reducing the pumping rate in existing pump-and-treat systems.

  17. Review on advanced of solar assisted chemical heat pump dryer for agriculture produce

    Energy Technology Data Exchange (ETDEWEB)

    Fadhel, M.I. [Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Faculty of Engineering and Technology, Multimedia University, Jalan Ayer Keroh Lama, 75450 Melaka (Malaysia); Sopian, K.; Daud, W.R.W.; Alghoul, M.A. [Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2011-02-15

    Over the past three decades there has been nearly exponential growth in drying R and D on a global scale. Improving of the drying operation to save energy, improve product quality as well as reduce environmental effect remained as the main objectives of any development of drying system. A solar assisted chemical heat pump dryer is a new solar drying system, which have contributed to better cost-effectiveness and better quality dried products as well as saving energy. A solar collector is adapted to provide thermal energy in a reactor so a chemical reaction can take place. This reduces the dependency of the drying technology on fossil energy for heating. In this paper a review on advanced of solar assisted chemical heat pump dryer is presented (the system model and the results from experimental studies on the system performance are discussed). The review of heat pump dryers and solar assisted heat pump dryer is presented. Description of chemical heat pump types and the overview of chemical heat pump dryer are discussed. The combination of chemical heat pump and solar technology gives extra efficiency in utilizing energy. (author)

  18. Excitons recombination investigation in CdSe/ZnS quantum dots solutions by pump-probe technique

    Science.gov (United States)

    Kulagina, A. S.; Danilov, V. V.; Shilov, V. B.; Grigorenko, K. M.; Vlasov, V. V.; Ermolaeva, G. M.

    2017-07-01

    It reports results of the pump-probe experiment on colloidal solutions of semiconductor CdSe/ZnS quantum dots with 5 nm diameter for intense pulsed resonant excitation at 560 nm wavelength. The dependence of intensity of a transmitted probe pulse on time delay relative to the pump pulse was used to determine relaxation time τexc of excited excitons in the QDs. The intensity of nonlinear reducing of QDs solution transmittance served the reason to set it for pump pulse. We found that the excited states in the QDs recombine within 300 ps after interaction with a 20-ps pump pulse.

  19. Innovations in pump design - what are future directions?:

    OpenAIRE

    Ivantysynova, Monika

    2009-01-01

    Displacement-controlled actuators, advanced continuously variable transmissions and hydraulic hybrid power trains represent new technologies formobile hydraulic machines, off road and on road vehicles. These new technologies allow major fuel savings and reduced emissions, but they change the performance requirements of positive displacement pumps and motors. Additionally, the market demand for positive displacement machines will increase. This paper briefly discusses these technology trends a...

  20. LOX/LH2 vane pump for auxiliary propulsion systems

    Science.gov (United States)

    Hemminger, J. A.; Ulbricht, T. E.

    1985-01-01

    Positive displacement pumps offer potential efficiency advantages over centrifugal pumps for future low thrust space missions. Low flow rate applications, such as space station auxiliary propulsion or dedicated low thrust orbiter transfer vehicles, are typical of missions where low flow and high head rise challenge centrifugal pumps. The positive displacement vane pump for pumping of LOX and LH2 is investigated. This effort has included: (1) a testing program in which pump performance was investigated for differing pump clearances and for differing pump materials while pumping LN2, LOX, and LH2; and (2) an analysis effort, in which a comprehensive pump performance analysis computer code was developed and exercised. An overview of the theoretical framework of the performance analysis computer code is presented, along with a summary of analysis results. Experimental results are presented for pump operating in liquid nitrogen. Included are data on the effects on pump performance of pump clearance, speed, and pressure rise. Pump suction performance is also presented.

  1. [Pharmacogenic osteoporosis beyond cortisone. Proton pump inhibitors, glitazones and diuretics].

    Science.gov (United States)

    Kann, P H; Hadji, P; Bergmann, R S

    2014-05-01

    [corrected] There are many drugs which can cause osteoporosis or at least favor its initiation. The effect of hormones and drugs with antihormonal activity, such as glucocorticoids and aromatase inhibitors, on initiation of osteoporosis is well known. In addition, proton pump inhibitors, glitazones and diuretics also influence the formation of osteoporosis. The results of currently available studies on the correlation between proton pump inhibitors, glitazones and diuretics on formation of osteoporosis were evaluated and summarized. Proton pump inhibitors and glitazones increase the risk for osteoporotic fractures. Loop diuretics may slightly increase fracture risk, whereas thiazides were shown to be osteoprotective by reducing fracture probability on a relevant scale. Proton pump inhibitors should not be prescribed without serious consideration and then only as long as necessary. Alternatively, the administration of the less effective H2 antagonists should be considered when possible due to the reduction of acid secretion. Because the long-term intake of thiazides is associated with a clinically relevant reduction in the risk of fractures and they are economic and well-tolerated, prescription can be thoroughly recommended within the framework of differential diagnostic considerations in an appropriate clinical context. The briefly increased risk of falling immediately after starting diuretic therapy is the only point which needs to be considered.

  2. An Energy Saving System for a Beam Pumping Unit

    Directory of Open Access Journals (Sweden)

    Hongqiang Lv

    2016-05-01

    Full Text Available Beam pumping units are widely used in the oil production industry, but the energy efficiency of this artificial lift machinery is generally low, especially for the low-production well and high-production well in the later stage. There are a number of ways for energy savings in pumping units, with the periodic adjustment of stroke speed and rectification of balance deviation being two important methods. In the paper, an energy saving system for a beam pumping unit (ESS-BPU based on the Internet of Things (IoT was proposed. A total of four types of sensors, including load sensor, angle sensor, voltage sensor, and current sensor, were used to detect the operating conditions of the pumping unit. Data from these sensors was fed into a controller installed in an oilfield to adjust the stroke speed automatically and estimate the degree of balance in real-time. Additionally, remote supervision could be fulfilled using a browser on a computer or smartphone. Furthermore, the data from a practical application was recorded and analyzed, and it can be seen that ESS-BPU is helpful in reducing energy loss caused by unnecessarily high stroke speed and a poor degree of balance.

  3. An Energy Saving System for a Beam Pumping Unit.

    Science.gov (United States)

    Lv, Hongqiang; Liu, Jun; Han, Jiuqiang; Jiang, An

    2016-05-13

    Beam pumping units are widely used in the oil production industry, but the energy efficiency of this artificial lift machinery is generally low, especially for the low-production well and high-production well in the later stage. There are a number of ways for energy savings in pumping units, with the periodic adjustment of stroke speed and rectification of balance deviation being two important methods. In the paper, an energy saving system for a beam pumping unit (ESS-BPU) based on the Internet of Things (IoT) was proposed. A total of four types of sensors, including load sensor, angle sensor, voltage sensor, and current sensor, were used to detect the operating conditions of the pumping unit. Data from these sensors was fed into a controller installed in an oilfield to adjust the stroke speed automatically and estimate the degree of balance in real-time. Additionally, remote supervision could be fulfilled using a browser on a computer or smartphone. Furthermore, the data from a practical application was recorded and analyzed, and it can be seen that ESS-BPU is helpful in reducing energy loss caused by unnecessarily high stroke speed and a poor degree of balance.

  4. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, B.; Hudon, K.; Christensen, D.

    2014-06-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt(tm) whole-house building simulations.

  5. Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, B.; Hudon, K.; Christensen, D.

    2014-06-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of U.S. climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt™ whole-house building simulations.

  6. Designing & Optimizing a Moving Magnet Pump for Liquid Sodium Systems

    Science.gov (United States)

    Hvasta, Michael G.

    Advanced materials such as NF-616, NF-709, HT-UPS, and silicon carbide (SiC) have greater strength than traditional structural materials such as 316-SS. Thus, using these high-strength materials to build sodium-cooled fast reactors (SFRs) could potentially reduce construction costs by lessening the required amount of material, and increase the efficiency of electromagnetic pumps by limiting ohmic heating within the pump duct walls. However, information pertaining to the sodium-compatibility of these alloys and ceramics is very sparse. Therefore, two separate test facilities were built to study the impact of both static and dynamic sodium corrosion The dynamic test facility enabled sodium corrosion to be studied under prototypic SFR operating conditions (T = 500 [C], V = 9.35 [m/s], CO = 2-3 [wppm]). The oxygen concentration, CO, within the dynamic test facility was maintained using a cold trap and measured with a plugging meter. The flow rate of the sodium was measured using a calibrated electromagnetic flowmeter. A moving magnet pump (MMP) was used to move the liquid sodium past the corrosion samples at a high velocity. Using newly developed theory, it was found that MMP performance could be accurately modeled and predicted for a wide variety of pump configurations.

  7. Position Sensorless Drive o SRM Mounted on Hydraulic Pump Unit

    Science.gov (United States)

    Kosaka, Takashi; Nabeya, Yoshinari; Ohyama, Kazunobu; Matsui, Nobuyuki

    Recently, Switched Reluctance Motors (SRM)have been applied to several industrial products such as fans, blowers, pumps and so forth because of their simple construction and relatively high e ciency.As one of the examples, Daikin Industries Ltd.has been successful in manufacturing hydraulic pump unit using 2.2kW three-phase SRM with shaft mounted position sensor for its control. This paper presents the position sensorless drive o the SRM for the purposes of reducing cost and down sizing of the hydraulic pump unit system.The controller, intentionally designed for this special application, realizes the following characteristics;the maximum and minimum speeds are 5000 and 300rpm, the speed response between the maximum and minimum speeds is within 100msec and the starting torque is less than 20% of the rated torque.The experimental studies using the hydraulic pump unit show that the proposed sensorless control scheme satis es the requirements for this application.

  8. Unsteady fluid flow in smart material actuated fluid pumps

    Science.gov (United States)

    John, Shaju; Cadou, Christopher

    2005-05-01

    Smart materials' ability to deliver large block forces in a small package while operating at high frequencies makes them extremely attractive for converting electrical to mechanical power. This has led to the development of hybrid actuators consisting of co-located smart material actuated pumps and hydraulic cylinders that are connected by a set of fast-acting valves. The overall success of the hybrid concept hinges on the effectiveness of the coupling between the smart material and the fluid. This, in turn, is strongly dependent on the resistance to fluid flow in the device. This paper presents results from three-dimensional unsteady simulations of fluid flow in the pumping chamber of a prototype hybrid actuator powered by a piezo-electric stack. The results show that the forces associated with moving the fluid into and out of the pumping chamber already exceed 10% of the piezo stack blocked force at relatively low frequencies ~120 Hz and approach 40% of the blocked force at 800 Hz. This reduces the amplitude of the piston motion in such a way that the volume flow rate remains approximately constant above operating frequencies of 500 Hz while the efficiency of the pump decreases rapidly.

  9. Diaphragm pico-liter pump for single-cell manipulation.

    Science.gov (United States)

    Anis, Yasser; Houkal, Jeffrey; Holl, Mark; Johnson, Roger; Meldrum, Deirdre

    2011-08-01

    A pico-liter pump is developed and integrated into a robotic manipulation system that automatically selects and transfers individual living cells of interest to analysis locations. The pump is a displacement type pump comprising one cylindrical chamber connected to a capillary micropipette. The top of the chamber is a thin diaphragm which, when deflected, causes the volume of the fluid-filled cylindrical chamber to change thereby causing fluid in the chamber to flow in and out of the micropipette. This enables aspirating and dispensing individual living cells. The diaphragm is deflected by a piezoelectric actuator that pushes against its center. The pump aspirates and dispenses volumes of fluid between 500 pL and 250 nL at flow rates up to 250 nL/s. The piezo-driven diaphragm arrangement provides exquisite control of the flow rate in and out of the capillary orifice. This feature, in turn, allows reduced perturbation of live cells by controlling and minimizing the applied shear stresses.

  10. Sarns centrifugal pump for repair of thoracic aortic injury: case reports.

    Science.gov (United States)

    Walls, J T; Curtis, J J; Boley, T

    1989-09-01

    A new centrifugal pump (Sarns), originally designed for ventricular assist, was successfully used in two patients during repair of traumatic pseudoaneurysm of the descending thoracic aorta. The distal thoracic aorta was perfused without heparinization to avoid spinal cord and visceral ischemia, reduce afterload on the heart, and avoid clamp injury to the aorta. Distal mean aortic pressure was maintained above 50 mm Hg with a mean pump flow of 1.75 liter/minute. Proposed structural advantages of the Sarns centrifugal pump for perfusion of the distal thoracic aorta without heparin are resistance to thrombus formation, air embolus, and hemolysis.

  11. Study and Test of Cold Storage Heat Recovery Heat Pump Coupled Solar Drying Device

    Directory of Open Access Journals (Sweden)

    Min Li

    2013-05-01

    Full Text Available In this study, we design the recovery of a heat pump combined solar drying device. Then, with this device, drying experiments of aquatic product, tilapia, were conducted, indicating that the newly designed device functions are well in temperature adjusting and controlling performance and showing that drying time is closely related to energy consumption and drying conditions. Heat recovery heat pump combined solar energy drier can improve the drying quality of aquatic products, but also can greatly reduce the drying energy consumption, which provides theoretical support to the design and processing of heat recovery heat pump of refrigeration system coupled solar drying device.

  12. Pediatric Insulin Pump Therapy: Reflecting on the First 10 Years of a Universal Funding Program in Ontario.

    Science.gov (United States)

    Shulman, Rayzel; Miller, Fiona A; Stukel, Thérèse A; Daneman, Denis; Guttmann, Astrid

    2017-01-01

    We evaluated the universal funding program for pediatric insulin pumps in Ontario by examining the dynamics underlying patterns of pump use and adverse events using population-based health administrative data available at the Institute for Clinical Evaluative Sciences (ICES), supplemented by other data. We found that (1) pump use has increased steadily since 2006 with variation across centres and disparity in use by socioeconomic status; (2) pump discontinuation is uncommon; (3) physicians value pump therapy in numerous ways that provide important insights into patterns of uptake; and (4) the safety profile of pump therapy is, in general, very good; however, individuals of lower socioeconomic status are at an increased risk of acute diabetes complications, most frequently diabetic ketoacidosis. This comprehensive mixed-methods evaluation reveals the need to understand and intervene to reduce social disparities in the use and adverse outcomes of technologies used for diabetes management.

  13. Wind power integration using individual heat pumps – Analysis of different heat storage options

    DEFF Research Database (Denmark)

    Hedegaard, Karsten; Mathiesen, Brian Vad; Lund, Henrik

    2012-01-01

    Significant installations of individual heat pumps are expected in future energy systems due to their economic competitiveness. This case study of the Danish energy system in 2020 with 50% wind power shows that individual heat pumps and heat storages can contribute to the integration of wind power...... reductions in excess electricity production and fuel consumption than heat accumulation tanks. Moreover, passive heat storage is found to be significantly more cost-effective than heat accumulation tanks. In terms of reducing fuel consumption of the energy system, the installation of heat pumps is the most...... important step. Adding heat storages only moderately reduces the fuel consumption. Model development has been made to facilitate a technical optimisation of individual heat pumps and heat storages in integration with the energy system....

  14. Simulation of groundwater and surface-water interaction and effects of pumping in a complex glacial-sediment aquifer, east central Massachusetts

    Science.gov (United States)

    Eggleston, Jack R.; Carlson, Carl S.; Fairchild, Gillian M.; Zarriello, Phillip J.

    2012-01-01

    The effects of groundwater pumping on surface-water features were evaluated by use of a numerical groundwater model developed for a complex glacial-sediment aquifer in northeastern Framingham, Massachusetts, and parts of surrounding towns. The aquifer is composed of sand, gravel, silt, and clay glacial-fill sediments up to 270 feet thick over an irregular fractured bedrock surface. Surface-water bodies, including Cochituate Brook, the Sudbury River, Lake Cochituate, Dudley Pond, and adjoining wetlands, are in hydraulic connection with the aquifer and can be affected by groundwater withdrawals. Groundwater and surface-water interaction was simulated with MODFLOW-NWT under current conditions and a variety of hypothetical pumping conditions. Simulations of hypothetical pumping at reactivated water supply wells indicate that captured groundwater would decrease baseflow to the Sudbury River and induce recharge from Lake Cochituate. Under constant (steady-state) pumping, induced groundwater recharge from Lake Cochituate was equal to about 32 percent of the simulated pumping rate, and flow downstream in the Sudbury River decreased at the same rate as pumping. However, surface water responded quickly to pumping stresses. When pumping was simulated for 1 month and then stopped, streamflow depletions decreased by about 80 percent within 2 months and by about 90 percent within about 4 months. The fast surface water response to groundwater pumping offers the potential to substantially reduce streamflow depletions during periods of low flow, which are of greatest concern to the ecological integrity of the river. Results indicate that streamflow depletion during September, typically the month of lowest flow, can be reduced by 29 percent by lowering the maximum pumping rates to near zero during September. Lowering pumping rates for 3 months (July through September) reduces streamflow depletion during September by 79 percent as compared to constant pumping. These results

  15. INVESTIGATION OF PERFORMANCE CURVES OF THREE STAGE DEEP WELL PUMPS

    OpenAIRE

    Gölcü, Mustafa

    2002-01-01

    In literature, pumps which are known as vertical turbine pump (VTP) have been designed to work vertically. Today, they are known as deep well pumps. These pumps are especially used in narrow and very deep wells where the surface sources are insufficient. Therefore, it is necessary to select suitable stage number to benefit from deep well pumps efficiently. In this study, a new deep well pump has been designed and the performances of three stage deep well pumps have been investigated experimen...

  16. Second insulin pump safety meeting: summary report.

    Science.gov (United States)

    Zhang, Yi; Jones, Paul L; Klonoff, David C

    2010-03-01

    Diabetes Technology Society facilitated a second meeting of insulin pump experts at Mills-Peninsula Health Services, San Mateo, California on November 4, 2009, at the request of the Food and Drug Administration, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories. The first such meeting was held in Bethesda, Maryland, on November 12, 2008. The group of physicians, nurses, diabetes educators, and engineers from across the United States discussed safety issues in insulin pump therapy and recommended adjustments to current insulin pump design and use to enhance overall safety. The meeting discussed safety issues in the context of pump operation; software; hardware; physical structure; electrical, biological, and chemical considerations; use; and environment from engineering, medical, nursing, and pump/user perspectives. There was consensus among meeting participants that insulin pump designs have made great progress in improving the quality of life of people with diabetes, but much more remains to be done.

  17. Diode-pumped laser altimeter

    Science.gov (United States)

    Welford, D.; Isyanova, Y.

    1993-01-01

    TEM(sub 00)-mode output energies up to 22.5 mJ with 23 percent slope efficiencies were generated at 1.064 microns in a diode-laser pumped Nd:YAG laser using a transverse-pumping geometry. 1.32-micron performance was equally impressive at 10.2 mJ output energy with 15 percent slope efficiency. The same pumping geometry was successfully carried forward to several complex Q-switched laser resonator designs with no noticeable degradation of beam quality. Output beam profiles were consistently shown to have greater than 90 percent correlation with the ideal TEM(sub 00)-order Gaussian profile. A comparison study on pulse-reflection-mode (PRM), pulse-transmission-mode (PTM), and passive Q-switching techniques was undertaken. The PRM Q-switched laser generated 8.3 mJ pulses with durations as short as 10 ns. The PTM Q-switch laser generated 5 mJ pulses with durations as short as 5 ns. The passively Q-switched laser generated 5 mJ pulses with durations as short as 2.4 ns. Frequency doubling of both 1.064 microns and 1.32 microns with conversion efficiencies of 56 percent in lithium triborate and 10 percent in rubidium titanyl arsenate, respectively, was shown. Sum-frequency generation of the 1.064 microns and 1.32 microns radiations was demonstrated in KTP to generate 1.1 mJ of 0.589 micron output with 11.5 percent conversion efficiency.

  18. Numerical Analysis of the Transient Behaviour of a Variable Speed Pump-Turbine during a Pumping Power Reduction Scenario

    Directory of Open Access Journals (Sweden)

    Giorgio Pavesi

    2016-07-01

    Full Text Available To achieve the carbon free electricity generation target for 2050, the penetration of renewable energy sources should further increase. To address the impacts of their unpredictable and intermittent characteristics on the future electricity grid, Pumped Hydro Energy Storage (PHES plants should enhance their regulation capability by extending their continuous operating range far beyond the optimal normal working range. However, for the time being, the regulation capability of the new generation of PHES, equipped with reversible pump-turbines due to their cost-effectiveness, is limited at part load by instability problems. The aim of this paper is to analyse, during a pumping power reduction scenario, the onset and development of unsteady phenomena leading to unstable behaviour. A 3D transient numerical simulation was carried out on the first stage of a variable-speed two-stage pump-turbine from full load to the unstable operating zone by progressively reducing the speed from 100% to 88% rpm corresponding to a power reduction from full load to about 60% with a ramp rate of 1.5% per s. Two three-dimensional unsteady flow structures affecting the return channel and the wicket gates at the end of the first stage were identified and their evolution in the power regulation scenario was fluid-dynamically and spectrally characterized to determine the fluid-dynamical conditions causing the head drop in the hump zone.

  19. Pump as Turbine (PAT) Design in Water Distribution Network by System Effectiveness

    OpenAIRE

    Oreste Fecarotta; Helena M. Ramos; Giuseppe Del Giudice; Armando Carravetta

    2013-01-01

    Water distribution networks face several problems related to leakages, where the pressure control strategy is a common practice for water loss management. Small-scale hydropower schemes, where pumps as turbines replace pressure reducing valves, can be considered an interesting technical solution, which ensures both economic convenience and system flexibility. Due to the water networks’ variable operating conditions, a new methodology to model the effectiveness of pumps as turbines was develop...

  20. Comparative evaluation of ground-coupled heat pumps that use solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, J.W.; Catan, M.A.

    1985-03-01

    A study of combined building space conditioning systems using both solar energy and heat pumps was conducted for the US Department of Energy (DOE). Several of these systems used the ground as a source or storage element for thermal energy, in order to reduce or eliminate the need for backup energy. This paper summarizes the results obtained for these systems in the United States, and describes the relationship of ground-coupling to the overall US solar-assisted heat-pump program.

  1. Sideload vanes for fluid pump

    Science.gov (United States)

    Erler, Scott R. (Inventor); Dills, Michael H. (Inventor); Rodriguez, Jose L. (Inventor); Tepool, John Eric (Inventor)

    2010-01-01

    A fluid pump assembly includes a rotatable component that can be rotated about an axis and a static vane assembly located adjacent to the rotatable component. The static vane assembly includes a circumferential surface axially spaced from the rotatable component, and one or more vanes extending from the circumferential surface toward the rotatable component. The one or more vanes are configured to produce a radial load on the rotatable component when the rotatable component is rotating about the axis and a fluid is present between the static vane assembly and the rotatable component.

  2. Magnetocaloric pump. [for cryogenic fluids

    Science.gov (United States)

    Brown, G. V. (Inventor)

    1974-01-01

    A vessel having inlet and outlet valves is disposed in a container with a fluid to be pumped which may be evolved from a liquid in the container below the vessel. A magnetocaloric substance is disposed in the vessel and causes fluid vapor in the vessel to expand and be expelled through the outlet valve. Vapor is drawn in through the inlet valve as the substance cools. The inlet valves may be one-way check valves or may be solenoid valves energized at appropriate times by timing circutis. A timer controlled heating element may also be disposed in the vessel to operate in conjunction with the magnetic field.

  3. Waveguide mutually pumped phase conjugators

    OpenAIRE

    James, S. W.; Youden, K.E.; Jeffrey, P. M.; EASON, R. W.; Chandler, P.J.; Zhang, L.; Townsend, P.D.

    1993-01-01

    The operation of the Bridge Mutually Pumped Phase Conjugator is reported in a planar waveguide structure in photorefractive BaTiO3. The waveguide was fabricated by the technique of ion implantation. using 1.5 MeV H+ at a dose of 10^16 ions/cm^2. An order of magnitude decrease in response time is observed in the waveguide as compared to typical values obtained in bulk crystals, probably resulting from a combination of the optical confinement within the waveguide, and possibly modification of t...

  4. Absorption-heat-pump system

    Science.gov (United States)

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  5. Carbon Dioxide Absorption Heat Pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    2002-01-01

    A carbon dioxide absorption heat pump cycle is disclosed using a high pressure stage and a super-critical cooling stage to provide a non-toxic system. Using carbon dioxide gas as the working fluid in the system, the present invention desorbs the CO2 from an absorbent and cools the gas in the super-critical state to deliver heat thereby. The cooled CO2 gas is then expanded thereby providing cooling and is returned to an absorber for further cycling. Strategic use of heat exchangers can increase the efficiency and performance of the system.

  6. Carbon Dioxide Absorption Heat Pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    2002-01-01

    A carbon dioxide absorption heat pump cycle is disclosed using a high pressure stage and a super-critical cooling stage to provide a non-toxic system. Using carbon dioxide gas as the working fluid in the system, the present invention desorbs the CO2 from an absorbent and cools the gas in the super-critical state to deliver heat thereby. The cooled CO2 gas is then expanded thereby providing cooling and is returned to an absorber for further cycling. Strategic use of heat exchangers can increase the efficiency and performance of the system.

  7. Integrated solar pump design incorporating a brushless DC motor for use in a solar heating system

    Energy Technology Data Exchange (ETDEWEB)

    Swan, Lukas G.; Allen, Peter L. [Department of Mechanical Engineering, Dalhousie University, 1360 Barrington Street, Halifax, Nova Scotia B3J 1Z1 (Canada)

    2010-09-15

    Most solar thermal hot water heating systems utilize a pump for circulation of the working fluid. An elegant approach to powering the pump is via solar energy. A ''solar pump'' employs a photovoltaic module, electric motor, and pump to collect and convert solar energy to circulate the working fluid. This article presents an experimental investigation of a new integrated solar pump design that employs the stator of a brushless DC motor and a magnetically coupled pump that has no dynamic seal. This design significantly reduces total volume and mass, and eliminates redundant components. The integrated design meets a hydraulic load of 1.7 bar and 1.4 litres per minute, equal to 4.0 watts, at a rotational speed of 500 revolutions per minute. The brushless DC motor and positive displacement pump achieve efficiencies of 62% and 52%, respectively, resulting in an electric to hydraulic efficiency of 32%. Thus, a readily available photovoltaic module rated 15 watts output is suitable to power the system. A variety of design variations were tested to determine the impact of the armature winding, pump size, pulse width modulation frequency, seal can material, etcetera. The physical and magnetic design was found to dominate efficiency. The efficiency characteristics of a photovoltaic module are such that over-sizing is wasteful. The integrated design presents a robust, efficient package for use as a solar pump. Although focus has been placed on application to a solar thermal collector system, variations of the design are suitable for a wide variety of applications such as remote location water pumping. (author)

  8. 46 CFR 109.329 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Fire pumps. 109.329 Section 109.329 Shipping COAST GUARD... of Safety Equipment § 109.329 Fire pumps. The master or person in charge shall insure that at least one of the fire pumps required in § 108.415 is ready for use on the fire main system at all times....

  9. The Hydraulic Ram (Or Impulse) Pump

    Science.gov (United States)

    Mills, Allan

    2014-01-01

    The hydraulic impulse pump utilizes a fraction of the momentum of a flowing stream to lift a small portion of that water to a higher level. There it may be accumulated in an elevated cistern to provide sufficient water for several families, for the pump works 24 h a day with no additional source of energy. The operation of the pump is described,…

  10. Pumped Storage and Potential Hydropower from Conduits

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2015-02-25

    Th is Congressional Report, Pumped Storage Hydropower and Potential Hydropower from Conduits, addresses the technical flexibility that existing pumped storage facilities can provide to support intermittent renewable energy generation. This study considered potential upgrades or retrofit of these facilities, the technical potential of existing and new pumped storage facilities to provide grid reliability benefits, and the range of conduit hydropower opportunities available in the United States.

  11. Vibrations of hydraulic pump and their solution

    OpenAIRE

    Dobšáková Lenka; Nováková Naděžda; Habán Vladimír; Hudec Martin; Jandourek Pavel

    2017-01-01

    The vibrations of hydraulic pump and connected pipeline system are very problematic and often hardly soluble. The high pressure pulsations of hydraulic pump with the double suction inlet are investigated. For that reason the static pressure and accelerations are measured. The numerical simulations are carried out in order to correlate computed data with experimental ones and assess the main source of vibrations. Consequently the design optimization of the inner hydraulic part of pump is done ...

  12. Reliability-Growth of Triplex Drilling Pump

    Institute of Scientific and Technical Information of China (English)

    Hou Yu; ZhaoZhong

    1996-01-01

    @@ Introduction to triplex pump The triplex pump widely used in oilfields is composed of power end assembly, fluid end assembly, piston-liner spraying system, lubrication system and charging system.The pump delivers mud into oil well. Through nozzles of drilling bit, the mud inside the drilling shaft comes to the annular space between drilling shaft and casing string and then returns to surface.

  13. Measuring Dynamic Transfer Functions of Cavitating Pumps

    Science.gov (United States)

    Baun, Daniel

    2007-01-01

    A water-flow test facility has been built to enable measurement of dynamic transfer functions (DTFs) of cavitating pumps and of inducers in such pumps. Originally, the facility was intended for use in an investigation of the effects of cavitation in a rocket-engine low-pressure oxygen turbopump. The facility can also be used to measure DTFs of cavitating pumps in general

  14. Linear peristaltic pump based on electromagnetic actuators

    Directory of Open Access Journals (Sweden)

    Maddoui Lotfi

    2014-01-01

    Full Text Available In this paper a study and design of a linear peristaltic pump are presented. A set of electromagnetic (solenoid actuators is used as the active tools to drag the liquid by crushing an elastic tube. The pump consists of six serially-connected electromagnetic actuators controlled via an electronic board. This may be considered as a simulated peristalsis action of intestines. The dynamic performances of the pump are investigated analytically and experimentally.

  15. Thin-disk laser pump schemes for large number of passes and moderate pump source quality

    Science.gov (United States)

    Schuhmann, Karsten; Hänsch, Theodor W.; Kirch, Klaus; Knecht, Andreas; Kottmann, Franz; Nez, Francois; Pohl, Randolf; Taqqu, David; Antognini, Aldo

    2015-11-01

    Novel thin-disk laser pump layouts are proposed yielding an increased number of passes for a given pump module size and pump source quality. These novel layouts result from a general scheme which bases on merging two simpler pump optics arrangements. Some peculiar examples can be realized by adapting standard commercially available pump optics simply by intro ducing an additional mirror-pair. More pump passes yield better efficiency, opening the way for usage of active materials with low absorption. In a standard multi-pass pump design, scaling of the number of beam passes brings ab out an increase of the overall size of the optical arrangement or an increase of the pump source quality requirements. Such increases are minimized in our scheme, making them eligible for industrial applications

  16. Thin-disk laser pump schemes for large number of passes and moderate pump source quality.

    Science.gov (United States)

    Schuhmann, Karsten; Hänsch, Theodor W; Kirch, Klaus; Knecht, Andreas; Kottmann, Franz; Nez, Francois; Pohl, Randolf; Taqqu, David; Antognini, Aldo

    2015-11-10

    Thin-disk laser pump layouts yielding an increased number of passes for a given pump module size and pump source quality are proposed. These layouts result from a general scheme based on merging two simpler pump optics arrangements. Some peculiar examples can be realized by adapting standard, commercially available pump optics with an additional mirror pair. More pump passes yield better efficiency, opening the way for the usage of active materials with low absorption. In a standard multipass pump design, scaling of the number of beam passes brings about an increase in the overall size of the optical arrangement or an increase in the pump source quality requirements. Such increases are minimized in our scheme, making them eligible for industrial applications.

  17. Thin-disk laser pump schemes for large number of passes and moderate pump source quality

    CERN Document Server

    Schuhmann, K; Kirch, K; Knecht, A; Kottmann, F; Nez, F; Pohl, R; Taqqu, D; Antognini, A

    2015-01-01

    Novel thin-disk laser pump layouts are proposed yielding an increased number of passes for a given pump module size and pump source quality. These novel layouts result from a general scheme which bases on merging two simpler pump optics arrangements. Some peculiar examples can be realized by adapting standard commercially available pump optics simply by intro ducing an additional mirror-pair. More pump passes yield better efficiency, opening the way for usage of active materials with low absorption. In a standard multi-pass pump design, scaling of the number of beam passes brings ab out an increase of the overall size of the optical arrangement or an increase of the pump source quality requirements. Such increases are minimized in our scheme, making them eligible for industrial applications

  18. A simplified heat pump model for use in solar plus heat pump system simulation studies

    DEFF Research Database (Denmark)

    Perers, Bengt; Andersen, Elsa; Nordman, Roger

    2012-01-01

    Solar plus heat pump systems are often very complex in design, with sometimes special heat pump arrangements and control. Therefore detailed heat pump models can give very slow system simulations and still not so accurate results compared to real heat pump performance in a system. The idea here...... is to start from a standard measured performance map of test points for a heat pump according to EN 14825 and then determine characteristic parameters for a simplified correlation based model of the heat pump. By plotting heat pump test data in different ways including power input and output form and not only...... as COP, a simplified relation could be seen. By using the same methodology as in the EN 12975 QDT part in the collector test standard it could be shown that a very simple model could describe the heat pump test data very accurately, by identifying 4 parameters in the correlation equation found....

  19. A simplified heat pump model for use in solar plus heat pump system simulation studies

    DEFF Research Database (Denmark)

    Perers, Bengt; Andersen, Elsa; Nordman, Roger

    2012-01-01

    Solar plus heat pump systems are often very complex in design, with sometimes special heat pump arrangements and control. Therefore detailed heat pump models can give very slow system simulations and still not so accurate results compared to real heat pump performance in a system. The idea here...... is to start from a standard measured performance map of test points for a heat pump according to EN 14825 and then determine characteristic parameters for a simplified correlation based model of the heat pump. By plotting heat pump test data in different ways including power input and output form and not only...... as COP, a simplified relation could be seen. By using the same methodology as in the EN 12975 QDT part in the collector test standard it could be shown that a very simple model could describe the heat pump test data very accurately, by identifying 4 parameters in the correlation equation found....

  20. F-AREA PUMP TANK 1 MIXING ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Tamburello, D; Richard Dimenna, R; Si Lee, S

    2008-11-05

    The F-area pump tanks are used to transfer supernate, sludge, and other materials. In any transfer, the solution must stay well mixed without allowing particulate matter to settle out of the liquid and, thus, accumulate in the bottom of the pump tank. Recently, the pulse jet mixing in F-area Pump Tank 1 (FPT1) has been decommissioned. An analysis of the liquid transfer through FPT1 has been performed using computational fluid dynamics (CFD) methods to assess whether or not the velocities throughout the tank will remain high enough to keep all particulate suspended using only transfer and recirculation pumps. The following paragraph is an abbreviated synopsis of the transfer procedure for FPT1 [1, 2]. Prior to a transfer, FPT1 begins to be filled with inhibited water through the inlet transfer line (TI). When the tank liquid level reaches 52.5 inches above the absolute tank bottom, the recirculation pump (RI and RO) is activated. At a tank liquid level of 72.5 inches above the absolute tank bottom, the outlet transfer line (TO) is activated to reduce the liquid level in FPT1 and transfer inhibited water to H-area Pump Tank 7 (HPT7). The liquid level is reduced down to 39.5 inches, with an allowable range from 37.5 to 41.5 inches above the absolute tank bottom. HPT7 goes through a similar procedure as FPT1 until both have tank liquid levels of approximately 39.5 inches above the absolute tank bottom. The transfer of inhibited water continues until a steady-state has been reached in both pump tanks. At this point, the supernate/sludge transfer begins with a minimum flow rate of 70 gpm and an average flow rate of 150 gpm. After the transfer is complete, the pump tanks (both FPT1 and HPT7) are pumped down to between 20.5 and 22.5 inches (above absolute bottom) and then flushed with 25,000 gallons of inhibited water to remove any possible sludge heal. After the flushing, the pump tanks are emptied. Note that the tank liquid level is measured using diptubes. Figure 2