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Sample records for superheater htf pump

  1. Hypersonic Tunnel Facility (HTF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Hypersonic Tunnel Facility (HTF) is a blow-down, non-vitiated (clean air) free-jet wind tunnel capable of testing large-scale, propulsion systems at Mach 5, 6,...

  2. Hypersonic Tunnel Facility (HTF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Hypersonic Tunnel Facility (HTF) is a blow-down, non-vitiated (clean air) free-jet wind tunnel capable of testing large-scale, propulsion systems at Mach 5, 6,...

  3. Computer modeling of a convective steam superheater

    Science.gov (United States)

    Trojan, Marcin

    2015-03-01

    Superheater is for generating superheated steam from the saturated steam from the evaporator outlet. In the case of pulverized coal fired boiler, a relatively small amount of ash causes problems with ash fouling on the heating surfaces, including the superheaters. In the convection pass of the boiler, the flue gas temperature is lower and ash deposits can be loose or sintered. Ash fouling not only reduces heat transfer from the flue gas to the steam, but also is the cause of a higher pressure drop on the flue gas flow path. In the case the pressure drop is greater than the power consumed by the fan increases. If the superheater surfaces are covered with ash than the steam temperature at the outlet of the superheater stages falls, and the flow rates of the water injected into attemperator should be reduced. There is also an increase in flue gas temperature after the different stages of the superheater. Consequently, this leads to a reduction in boiler efficiency. The paper presents the results of computational fluid dynamics simulations of the first stage superheater of both the boiler OP-210M using the commercial software. The temperature distributions of the steam and flue gas along the way they flow together with temperature of the tube walls and temperature of the ash deposits will be determined. The calculated steam temperature is compared with measurement results. Knowledge of these temperatures is of great practical importance because it allows to choose the grade of steel for a given superheater stage. Using the developed model of the superheater to determine its degree of ash fouling in the on-line mode one can control the activation frequency of steam sootblowers.

  4. Computer modeling of a convective steam superheater

    Directory of Open Access Journals (Sweden)

    Trojan Marcin

    2015-03-01

    Full Text Available Superheater is for generating superheated steam from the saturated steam from the evaporator outlet. In the case of pulverized coal fired boiler, a relatively small amount of ash causes problems with ash fouling on the heating surfaces, including the superheaters. In the convection pass of the boiler, the flue gas temperature is lower and ash deposits can be loose or sintered. Ash fouling not only reduces heat transfer from the flue gas to the steam, but also is the cause of a higher pressure drop on the flue gas flow path. In the case the pressure drop is greater than the power consumed by the fan increases. If the superheater surfaces are covered with ash than the steam temperature at the outlet of the superheater stages falls, and the flow rates of the water injected into attemperator should be reduced. There is also an increase in flue gas temperature after the different stages of the superheater. Consequently, this leads to a reduction in boiler efficiency. The paper presents the results of computational fluid dynamics simulations of the first stage superheater of both the boiler OP-210M using the commercial software. The temperature distributions of the steam and flue gas along the way they flow together with temperature of the tube walls and temperature of the ash deposits will be determined. The calculated steam temperature is compared with measurement results. Knowledge of these temperatures is of great practical importance because it allows to choose the grade of steel for a given superheater stage. Using the developed model of the superheater to determine its degree of ash fouling in the on-line mode one can control the activation frequency of steam sootblowers.

  5. Thermal Analysis of Superheater Platen Tubesin Boilers

    Directory of Open Access Journals (Sweden)

    Shahram Falahatkar

    2014-01-01

    Full Text Available Superheaters are among the most important components of boilers and have major importance due to this operation in high temperatures and pressures. Turbines are sensitive to the fluctuation of superheaterstemperature;therefore even the slightest fluctuation in the outlet vapor temperature from the superheaters does damage the turbine axis and fins. Examining the potential damages of combustion in the boilers and components such as the superheaters can have a vital contribution to the progression of the productivity of boiler, turbine and the power plant altogether it solutions are to be fund to improve such systems. In this study, the focus is on the nearest tube set of superheaters to the combustion chamber.These types of tubes are exposed to a wide range ofcombustion flames such that the most heat transfer to them is radiation type.Here, the 320 MW boiler of Isfahan power plant (Iran, the combustion chamber, 16 burners and the platensuperheater tubes were remodeled by CFD technique. The fluid motion, the heat transfer and combustion processes are analyzed. The two-equation turbulence model of k-εis adopted to measure the eddy viscosity. The eddy dissipation model is used to calculate the combustion as well as the P-1 radiation model to quantify the radiation. The overheated zones of superheater tubes and the combustion chamber are identified in order toimprove this problem by applying the radiation thermal shields and knees with porous crust which are introduced as the new techniques.

  6. Analytical Results from Salt Solution Feed Tank (SSFT) Samples HTF-16-6 and HTF-16-40

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-09-23

    Two samples from the Salt Solution Feed Tank (SSFT) were analyzed by SRNL, HTF-16-6 and HTF-16-40. Multiple analyses of these samples indicate a general composition almost identical to that of the Salt Batch 8-B feed and the Tank 21H sample results.

  7. Determination of superheat limit of liquids using fluctuation theory

    Institute of Scientific and Technical Information of China (English)

    曾丹苓; 敬成君

    1996-01-01

    The theoretical superheat limit of liquids in homogeneous nucleate boiling is determined. A new hypothesis to define the superheat limit is proposed on the basis of the fluctuation theory in statistical thermodynamics. Using Gibbs canonical and grand canonical ensemble formulas, the superheat limit are derived. The numerical results are in good agreement with those in literature.

  8. Analysis of Superheater Work Under Creep Conditions

    Directory of Open Access Journals (Sweden)

    Piotr Duda

    2015-03-01

    Full Text Available The aim of this article is work modelling of superheater SH3. It is made of the austenitic stainless steel Super 304H. Its design temperature T is 604 C, and the design pressure P acting on the inner surface of the pipes is 284 bar. The high temperature is the reason of the superheater work under creep conditions. In this article calculations of the optimally mounted coil superheater SH3 are presented. The calculations are carried out first on the basis of the applicable European standards and with the help of the Auto Pipe program. Then, calculations are performed using the ANSYS program based on conducted creep tests and proposed creep equation. The coefficients in creep equation are determined based on the research conducted at the Instytut Metalurgii Żelaza in Gliwice. The model approximates the creep strain as the function of time and stress and this function is presented in the form of a three-dimensional surface . The results of calculations by both methods will be compared and conclusions will be presented. The performed analyzes can estimate the superheater coil remnant life and the usage after the selected time of its operation.

  9. Characterization of the March 2017 tank 10 surface sample (combination of HTF-10-17-30 AND HTF-10-17-31) and variable depth sample (combination of HTF-10-17-32 and HTF-10-17-33)

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-19

    Two surface samples (HTF-10-17-30 and HTF-10-17-31) and two variable depth samples (HTF-10-17-32 and HTF-10-17-33) were collected from SRS Tank 10 during March 2017 and submitted to SRNL for characterization. At SRNL, the two surface samples were combined in one container, the two variable depth samples (VDSs) were combined in another container, and then the two composite samples were each characterized by a series of physical, ionic, radiological, and elemental analysis methods. The surface sample composite was characterized primarily for Tank Farm corrosion control purposes, while the VDS composite was characterized primarily for Tank Closure Cesium Removal (TCCR) purposes.

  10. Superheater Tube Flat Wall Stationary Temperature Field

    Directory of Open Access Journals (Sweden)

    Parpiev A.T.

    2016-01-01

    Full Text Available The BKZ-220-100-9 steam generator platen superheater tube flat wall stationary temperature fields analysis have been made. The six steel grades, using in boiler fabrication, namely, St. 10, St. 20, 12H1MF, 15HM, 1H18N9T and 12H18N12T, have been used. The temperature curves calculation has been made by using outer and inner surface heat-transfer coefficients nine different combinations.

  11. Nonlinear Superheat and Evaporation Temperature Control of a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes novel control of the superheat of the evaporator in a refrigeration system. A new model of the evaporator is developed and based on this model the superheat is transferred to a referred variable. It is shown that control of this variable leads to a linear system independent...

  12. Nonlinear Superheat Control of a Refrigeration Plant using Backstepping

    DEFF Research Database (Denmark)

    Rasmussen, Henrik

    2008-01-01

    This paper proposes a novel method for superheat and capacity control of refrigeration systems. The main idea is to control the superheat by the compressor speed and capacity by the refrigerant flow. A new low order nonlinear model of the evaporator is developed and used in a backstepping design...

  13. Automatic Tuning of the Superheat Controller in a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes an automatic tuning of the superheat control in a refrigeration system using a relay method. By means of a simple evaporator model that captures the important dynamics and non-linearities of the superheat a gain-scheduling that compensates for the variation of the process gain...

  14. Effect of superheat and electric field on saturated film boiling

    Science.gov (United States)

    Pandey, Vinod; Biswas, Gautam; Dalal, Amaresh

    2016-05-01

    The objective of this investigation is to study the influence of superheat temperature and applied uniform electric field across the liquid-vapor interface during film boiling using a coupled level set and volume of fluid algorithm. The hydrodynamics of bubble growth, detachment, and its morphological variation with electrohydrodynamic forces are studied considering the medium to be incompressible, viscous, and perfectly dielectric at near critical pressure. The transition in interfacial instability behavior occurs with increase in superheat, the bubble release being periodic both in space and time. Discrete bubble growth occurs at a smaller superheat whereas vapor columns form at the higher superheat values. Destabilization of interfacial motion due to applied electric field results in decrease in bubble separation distance and increase in bubble release rate culminating in enhanced heat transfer rate. A comparison of maximum bubble height owing to application of different intensities of electric field is performed at a smaller superheat. The change in dynamics of bubble growth due to increasing superheat at a high intensity of electric field is studied. The effect of increasing intensity of electric field on the heat transfer rate at different superheats is determined. The boiling characteristic is found to be influenced significantly only above a minimum critical intensity of the electric field.

  15. Characterizing lateral resolution of interferometers: the Height Transfer Function (HTF)

    Science.gov (United States)

    Doerband, B.; Hetzler, J.

    2005-08-01

    The lateral resolution of an interferometer is limited mainly by the design of the optical arrangement as well as the size of the beam stop. For its characterization the MTF1,2 is not very useful. The height of a structure normal to the surface under test is transferred into a phase of a reflected wavefront. Since imaging mechanisms for intensity and phase are very different, we propose a Height Transfer Function (HTF) to describe the lateral resolution of interferometers. The HTF shows the quotient of the reconstructed and the original height of a sine-modulated surface structure as a function of the spatial frequency. The HTF can be measured with a test sample of varying periodical surface profiles and spacings. Simulations can be made using a combination of geometrical ray tracing and Fourier transformation techniques. Two different layouts of null systems for the test of an asphere are compared. A device to measure the HTF is shown along with results for a variety of different interferometers.

  16. Neural network for prediction of superheater fireside corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Makkonen, P. [Foster Wheeler Energia Oy, Karhula R and D Center, Karhula (Finland)

    1998-12-31

    Superheater corrosion causes vast annual losses to the power companies. If the corrosion could be reliably predicted, new power plants could be designed accordingly, and knowledge of fuel selection and determination of process conditions could be utilized to minimize superheater corrosion. If relations between inputs and the output are poorly known, conventional models depending on corrosion theories will fail. A prediction model based on a neural network is capable of learning from errors and improving its performance as the amount of data increases. The neural network developed during this study predicts superheater corrosion with 80 % accuracy at early stage of the project. (orig.) 10 refs.

  17. Failure of steam superheater tube of reformer heater

    Energy Technology Data Exchange (ETDEWEB)

    Shalaby, H.; Riad, W.; Rajab, M. [Petroleum Research and Studies Center, Kuwait Institute for Scientific Research P.O. Box 24885, 13109 Safat (Kuwait)

    2004-07-01

    During hydro-test and shutdown of hydrogen production unit, leak was observed at a local refinery on one convection section superheater steam tubes of a reformer. The leaky tube was pulled out and a complete failure investigation was conducted. The failure of the superheater tubes was attributed to oxygen pits that occurred during idle periods. During shutdowns, condensed moisture and atmospheric oxygen combined to produce the observed pits that are reddish in colors. It was recommended that proper procedures be followed during shutdown of the superheater to avoid water condensation and ingress of atmospheric oxygen. (authors)

  18. Identity between rat htf and human xbp-1 genes: determination of gene structure, target sequence, and transcription promotion function for HTF.

    Science.gov (United States)

    Kokura, K; Kishimoto, T; Tamura, T

    2000-01-11

    Hepatocarcinogenesis-related transcription factor (HTF) was originally isolated from rats in which the expression was enhanced in hepatocellular carcinomas. Rat HTF (rHTF) is structurally similar to human X-box-binding protein-1 (hXBP-1), and both factors are unique in respective genomes. A previous study showed that hXBP-1 mRNA is detectable ubiquitously but is enriched in the human liver as rHTF. In this study, we demonstrated the analogous exon-intron organization and significant sequence homology for rhtf and hxbp-1 genes. Alignment of amino acid sequences of rHTF and hXBP-1 revealed that all the characteristic motifs in rHTF were conserved in hXBP-1. Moreover, Southern blotting patterns provided with the rHTF and hXBP-1 probes were basically the same. These two genes were thus thought to belong to the same evolutional lineage. We determined the consensus binding sequence (CRCGTCA) for rHTF by CASTing, and it was found to be nearly the same as that for hXBP-1. Transactivation ability of rHTF was also demonstrated. The rhtf gene generates two types of mRNAs (2.0 kb and 2.5 kb), both of which encode identical rHTF protein. These transcripts had distinct transcription initiation sites. The 2.0 kb promoter, that was revealed by the transient luciferase assay, contained GC-box and CAAT-box. Sequences around the transcription initiation site for the 2.0 kb transcript were similar in rhtf and hxbp-1 genes. Our observations suggest that HTF is a rat homolog of hXBP-1.

  19. Nonlinear Superheat and Evaporation Temperature Control of a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes novel control of the superheat of the evaporator in a refrigeration system. A new model of the evaporator is developed and based on this model the superheat is transferred to a referred variable. It is shown that control of this variable leads to a linear system independent...... of the working point. The model also gives a method for control of the evaporation temperature. The proposed method is validated by experimental results....

  20. Analysis of superheater's pipe wall overtemperature by fault tree diagnose

    Institute of Scientific and Technical Information of China (English)

    盛德仁; 任浩仁; 陈坚红; 李蔚

    2002-01-01

    After research on a 2000t/h subcritical forced-circulation balanced v entilation were applied boiler and the structure and operation of its auxiliary system builds up this heat transfer model of a superheater's pipe wall and analy ze the effect of primary factors on the overtemperature of the pipe wall. Fault tree structure was used to uncover the multiplayer logic between the overtempera ture of the superheater's pipe wall and the faults.

  1. 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.

  2. Limit of Superheat of Polystyrene-Cyclohexane Solutions: Theory

    Directory of Open Access Journals (Sweden)

    John Howland Jennings

    2012-06-01

    Full Text Available A theory for the surface tension of polymer solutions is used along with classical nucleation theory to predict the temperature rise above the solvent limit of superheat due to addition of polymer.  Polystyrene, of 2000 and 4000 molecular weight, was added to cyclohexane and it produced a linear rise in the superheat to an extent that depends upon both molecular weight and concentration.  The theory is used in the athermal case (dT = 0 to give the additional temperature rise with respect to weight fraction.

  3. SEM Investigation of Superheater Deposits from Biomass-Fired Boilers

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt; Frandsen, Flemming; Hansen, Jørn

    2004-01-01

    , mature superheater deposit samples were extracted from two straw-fired boilers, Masnedø and Ensted, with fuel inputs of 33 MWth and 100 MWth, respectively. SEM (scanning electron microscopy) images and EDX (energy dispersive X-ray) analyses were performed on the deposit samples. Different strategies...

  4. Integrated boiler, superheater, and decomposer for sulfuric acid decomposition

    Science.gov (United States)

    Moore, Robert; Pickard, Paul S.; Parma, Jr., Edward J.; Vernon, Milton E.; Gelbard, Fred; Lenard, Roger X.

    2010-01-12

    A method and apparatus, constructed of ceramics and other corrosion resistant materials, for decomposing sulfuric acid into sulfur dioxide, oxygen and water using an integrated boiler, superheater, and decomposer unit comprising a bayonet-type, dual-tube, counter-flow heat exchanger with a catalytic insert and a central baffle to increase recuperation efficiency.

  5. Nonlinear superheat and capacity control of a refrigeration plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Larsen, Lars F. S.

    2009-01-01

    This paper proposes a novel method for superheat and capacity control of refrigeration systems. A new low order nonlinear model of the evaporator is developed and used in a backstepping design of a nonlinear controller. The stability of the proposed method is validated theoretically by Lyapunov a...

  6. Current Status of Superheat Spray Modeling With NCC

    Science.gov (United States)

    Raju, M. S.; Bulzan, Dan L.

    2012-01-01

    An understanding of liquid fuel behavior at superheat conditions is identified to be a topic of importance in the design of modern supersonic engines. As a part of the NASA's supersonics project office initiative on high altitude emissions, we have undertaken an effort to assess the accuracy of various existing CFD models used in the modeling of superheated sprays. As a part of this investigation, we have completed the implementation of a modeling approach into the national combustion code (NCC), and then applied it to investigate the following three cases: (1) the validation of a flashing jet generated by the sudden release of pressurized R134A from a cylindrical nozzle, (2) the differences between two superheat vaporization models were studied based on both hot and cold flow calculations of a Parker-Hannifin pressure swirl atomizer, (3) the spray characteristics generated by a single-element LDI (Lean Direct Injector) experiment were studied to investigate the differences between superheat and non-superheat conditions. Further details can be found in the paper.

  7. Mach 5 to 7 RBCC Propulsion System Testing at NASA-LeRC HTF

    Science.gov (United States)

    Perkins, H. Douglas; Thomas, Scott R.; Pack, William D.

    1996-01-01

    A series of Mach 5 to 7 freejet tests of a Rocket Based Combined Cycle (RBCC) engine were cnducted at the NASA Lewis Research Center (LERC) Hypersonic Tunnel Facility (HTF). This paper describes the configuration and operation of the HTF and the RBCC engine during these tests. A number of facility support systems are described which were added or modified to enhance the HTF test capability for conducting this experiment. The unfueled aerodynamic perfor- mance of the RBCC engine flowpath is also presented and compared to sub-scale test results previously obtained in the NASA LERC I x I Supersonic Wind Tunnel (SWT) and to Computational Fluid Dynamic (CFD) analysis results. This test program demonstrated a successful configuration of the HTF for facility starting and operation with a generic RBCC type engine and an increased range of facility operating conditions. The ability of sub-scale testing and CFD analysis to predict flowpath performance was also shown. The HTF is a freejet, blowdown propulsion test facility that can simulate up to Mach 7 flight conditions with true air composition. Mach 5, 6, and 7 facility nozzles are available, each with an exit diameter of 42 in. This combination of clean air, large scale, and Mach 7 capabilities is unique to the HTF. This RBCC engine study is the first engine test program conducted at the HTF since 1974.

  8. High-Temperature Graphitization Failure of Primary Superheater Tube

    Science.gov (United States)

    Ghosh, D.; Ray, S.; Roy, H.; Mandal, N.; Shukla, A. K.

    2015-12-01

    Failure of boiler tubes is the main cause of unit outages of the plant, which further affects the reliability, availability and safety of the unit. So failure analysis of boiler tubes is absolutely essential to predict the root cause of the failure and the steps are taken for future remedial action to prevent the failure in near future. This paper investigates the probable cause/causes of failure of the primary superheater tube in a thermal power plant boiler. Visual inspection, dimensional measurement, chemical analysis, metallographic examination and hardness measurement are conducted as the part of the investigative studies. Apart from these tests, mechanical testing and fractographic analysis are also conducted as supplements. Finally, it is concluded that the superheater tube is failed due to graphitization for prolonged exposure of the tube at higher temperature.

  9. A fault tolerant superheat control strategy for supermarket refrigeration systems

    DEFF Research Database (Denmark)

    Vinther, Kasper; Izadi-Zamanabadi, Roozbeh; Rasmussen, Henrik

    2013-01-01

    In this paper, a fault tolerant control (FTC) strategy is proposed for evaporator superheat control in supermarket refrigeration systems. Conventional control uses a pressure and temperature sensor for this purpose, however, the pressure sensor can fail to function. A contingency control strategy......, based on a maximum slope-seeking control method and only a single temperature sensor, is developed to drive the evaporator outlet temperature to a level that gives a suitable superheat of the refrigerant. The FTC strategy requires no a priori system knowledge or additional hardware and functions...... in a plug & play fashion. The strategy is outlined by means of procedural steps as well as a flow chart that also illustrates the process of automatic tuning of the maximum slope-seeking controller. Test results are furthermore presented for a display case in a full scale CO2 supermarket refrigeration...

  10. SDZ HTF 919 stimulates canine colonic motility and transit in vivo.

    Science.gov (United States)

    Nguyen, A; Camilleri, M; Kost, L J; Metzger, A; Sarr, M G; Hanson, R B; Fett, S L; Zinsmeister, A R

    1997-03-01

    Effects of the nonbenzamide 5-hydroxytryptamine4 agonist SDZ HTF 919 on gastrointestinal motility are unclear. Our aim was to assess the in vivo effects on gastrointestinal and colonic transit of radiolabeled residue and on colonic phasic contractility. In six female dogs, transit was measured over a period of 2 days by radioscintigraphy and colonic motility was measured by pneumohydraulic perfusion manometry of the proximal and distal colon. SDZ HTF 919 was administered initially by bolus i.v. infusion, followed by s.c. injection 8 and 16 hr later. Doses tested were 0.03, 0.1 and 0.3 mg/kg, and isotonic saline and vehicle served as controls in each dog. Stomach and small bowel transit was not significantly altered by SDZ HTF 919. Overall, i.v. SDZ HTF 919 accelerated colonic transit during the first 1 hr, compared with controls. These effects were significant even with the lowest dose of SDZ HTF 919. Responses to higher infusion doses were more variable. SDZ HTF 919 did not cause significant changes in quantitative pressure indices, such as amplitude or motor index, in the small bowel or colon. Prolonged postprandial colonic contractions, each lasting >30 sec, were noted after each i.v. agent and were significantly more frequent with the 0.03 mg/kg dose than with control (vehicle) treatment. Thus, SDZ HTF 919 accelerates canine colonic transit in vivo during the first 1 hr after i.v. administration. SDZ HTF 919 appears to be a promising agent for stimulation of mammalian colonic transit.

  11. Characterization of the March 2017 Tank 15 Waste Removal Slurry Sample (Combination of Slurry Samples HTF-15-17-28 and HTF-15-17-29)

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coleman, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-05-09

    Two March 2017 Tank 15 slurry samples (HTF-15-17-28 and HTF-15-17-29) were collected during the second bulk waste removal campaign and submitted to SRNL for characterization. At SRNL, the two samples were combined and then characterized by a series of physical, elemental, radiological, and ionic analysis methods. Sludge settling as a function of time was also quantified. The characterization results reported in this document are consistent with expectations based upon waste type, process knowledge, comparisons between alternate analysis techniques, and comparisons with the characterization results obtained for the November 2016 Tank 15 slurry sample (the sample collected during the first bulk waste removal campaign).

  12. The Mothball, Sustainment, and Proposed Reactivation of the Hypersonic Tunnel Facility (HTF) at NASA Glenn Research Center Plum Brook Station

    Science.gov (United States)

    Thomas, Scott R.; Lee, Jinho; Stephens, John W.; Hostler, Robert W., Jr.; VonKamp, William D.

    2010-01-01

    The Hypersonic Tunnel Facility (HTF) located at the NASA Glenn Research Center s Plum Brook Station in Sandusky, Ohio, is the nation s only large-scale, non-vitiated, hypersonic propulsion test facility. The HTF, with its 4-story graphite induction heater, is capable of duplicating Mach 5, 6, and 7 flight conditions. This unique propulsion system test facility has experienced several standby and reactivation cycles. The intent of the paper is to overview the HTF capabilities to the propulsion community, present the current status of HTF, and share the lessons learned from putting a large-scale facility into mothball status for a later restart

  13. Alkali chloride induced corrosion of superheaters under biomass firing conditions: Improved insights from laboratory scale studies

    DEFF Research Database (Denmark)

    Okoro, Sunday Chukwudi; Montgomery, Melanie; Jappe Frandsen, Flemming

    2015-01-01

    to the formation of corrosive deposits (rich in alkali chlorides) on the surfaces of the superheaters. Accordingly, an extensive number of fundamental investigations have been undertaken to understand the basic mechanisms behind the alkali chloride induced high temperature corrosion of superheaters (for example...

  14. Investigation of Sensible and Latent Heat Storage System using various HTF

    Science.gov (United States)

    Beemkumar, N.; Karthikeyan, A.; Manoj, A.; Keerthan, J. S.; Stallan, Joseph Paul; Amithkishore, P.

    2017-05-01

    The objective of the work is investigating the latent heat storage system by varying heat transfer fluid (HTF). In this experiment, the effect of using different heat transfer fluids on the combined system is studied while using a low melting phase change material (PCM) i.e., paraffin wax. The heat transfer fluids chosen are water (low boiling fluid) and Therminol-66 (High boiling fluid). A comparison is made between the heat transfers by employing both the Heat transfer fluids. In the beginning, water is made to flow as the HTF and the charging process is undertaken followed by the discharging process by utilizing the different encapsulation materials namely, copper, aluminium and brass. These processes are then repeated for therminol-66 as HTF. At the end of the experiment it was concluded that even though therminol-66 enhances the latent heat storage capacity, water offers a higher sensible heat storage capacity, making it a better HTF for low melting PCM. Similar to above said process the experiments can be conducted for high and medium range melting point PCM with variation of HTF.

  15. Deposit-related failures of boiler superheater tubing and steam piping

    Energy Technology Data Exchange (ETDEWEB)

    Kotwica, D.J. [Betz Labs. Inc., The Woodlands, TX (United States)

    1995-12-01

    Deposition in superheater tubing can originate from the carryover of water droplets into the superheater bank from the steam drum. Deposition occurs because the concentration of impurities present in the entrained water droplets can be several orders of magnitude greater than that present in steam alone. When the water flashes to steam in the superheater, salts, hardness species, and corrosion products dissolved or suspended in the water build-up on the internal surfaces of the superheater tubing. The detrimental effects of carryover deposition in superheater tubing has been shown to contribute to at least three types of failure: stress-corrosion cracking, overheating, and corrosion gouging. A case history illustrating each one of these failure mechanisms is presented.

  16. ANALYSIS OF 2H-EVAPORATOR SCALE WALL [HTF-13-82] AND POT BOTTOM [HTF-13-77] SAMPLES

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L.

    2013-06-21

    Savannah River Remediation (SRR) is planning to remove a buildup of sodium aluminosilicate scale from the 2H-evaporator pot by loading and soaking the pot with heated 1.5 M nitric acid solution. Sampling and analysis of the scale material has been performed so that uranium and plutonium isotopic analysis can be input into a Nuclear Criticality Safety Assessment (NCSA) for scale removal by chemical cleaning. Historically, since the operation of the Defense Waste Processing Facility (DWPF), silicon in the DWPF recycle stream combines with aluminum in the typical tank farm supernate to form sodium aluminosilicate scale mineral deposits in the 2Hevaporator pot and gravity drain line. The 2H-evaporator scale samples analyzed by Savannah River National Laboratory (SRNL) came from the bottom cone sections of the 2H-evaporator pot [Sample HTF-13-77] and the wall 2H-evaporator [sample HTF-13-82]. X-ray diffraction analysis (XRD) confirmed that both the 2H-evaporator pot scale and the wall samples consist of nitrated cancrinite (a crystalline sodium aluminosilicate solid) and clarkeite (a uranium oxy-hydroxide mineral). On “as received” basis, the bottom pot section scale sample contained an average of 2.59E+00 ± 1.40E-01 wt % total uranium with a U-235 enrichment of 6.12E-01 ± 1.48E-02 %, while the wall sample contained an average of 4.03E+00 ± 9.79E-01 wt % total uranium with a U-235 enrichment of 6.03E-01% ± 1.66E-02 wt %. The bottom pot section scale sample analyses results for Pu-238, Pu-239, and Pu-241 are 3.16E- 05 ± 5.40E-06 wt %, 3.28E-04 ± 1.45E-05 wt %, and <8.80E-07 wt %, respectively. The evaporator wall scale samples analysis values for Pu-238, Pu-239, and Pu-241 averages 3.74E-05 ± 6.01E-06 wt %, 4.38E-04 ± 5.08E-05 wt %, and <1.38E-06 wt %, respectively. The Pu-241 analyses results, as presented, are upper limit values. These results are provided so that SRR can calculate the equivalent uranium-235 concentrations for the NCSA. Results confirm that

  17. Analysis Of 2H-Evaporator Scale Wall [HTF-13-82] And Pot Bottom [HTF-13-77] Samples

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. N.

    2013-09-11

    Savannah River Remediation (SRR) is planning to remove a buildup of sodium aluminosilicate scale from the 2H-evaporator pot by loading and soaking the pot with heated 1.5 M nitric acid solution. Sampling and analysis of the scale material has been performed so that uranium and plutonium isotopic analysis can be input into a Nuclear Criticality Safety Assessment (NCSA) for scale removal by chemical cleaning. Historically, since the operation of the Defense Waste Processing Facility (DWPF), silicon in the DWPF recycle stream combines with aluminum in the typical tank farm supernate to form sodium aluminosilicate scale mineral deposits in the 2H-evaporator pot and gravity drain line. The 2H-evaporator scale samples analyzed by Savannah River National Laboratory (SRNL) came from two different locations within the evaporator pot; the bottom cone sections of the 2H-evaporator pot [Sample HTF-13-77] and the wall 2H-evaporator [sample HTF-13-82]. X-ray diffraction analysis (XRD) confirmed that both the 2H-evaporator pot scale and the wall samples consist of nitrated cancrinite (a crystalline sodium aluminosilicate solid) and clarkeite (a uranium oxyhydroxide mineral). On ''as received'' basis, the bottom pot section scale sample contained an average of 2.59E+00 {+-} 1.40E-01 wt % total uranium with a U-235 enrichment of 6.12E-01 {+-} 1.48E-02 %, while the wall sample contained an average of 4.03E+00 {+-} 9.79E-01 wt % total uranium with a U-235 enrichment of 6.03E-01% {+-} 1.66E-02 wt %. The bottom pot section scale sample analyses results for Pu-238, Pu-239, and Pu-241 are 3.16E-05 {+-} 5.40E-06 wt %, 3.28E-04 {+-} 1.45E-05 wt %, and <8.80E-07 wt %, respectively. The evaporator wall scale samples analysis values for Pu-238, Pu-239, and Pu-241 averages 3.74E-05 {+-} 6.01E-06 wt %, 4.38E-04 {+-} 5.08E-05 wt %, and <1.38E-06 wt %, respectively. The Pu-241 analyses results, as presented, are upper limit values. For these two evaporator scale samples

  18. Attainable superheat of argon-helium, argon-neon solutions.

    Science.gov (United States)

    Baidakov, Vladimir G; Kaverin, Aleksey M; Andbaeva, Valentina N

    2008-10-16

    The method of lifetime measurement has been used to investigate the kinetics of spontaneous boiling-up of superheated argon-helium and argon-neon solutions. Experiments were made at a pressure of p = 1.5 MPa and concentrations up to 0.33 mol% in the range of nucleation rates from 10 (4) to 10 (8) s (-1) m (-3). The homogeneous nucleation regime has been distinguished. With good agreement between experimental data and homogeneous nucleation theory in temperature and concentration dependences of the nucleation rate, a systematic underestimation by 0.25-0.34 K has been revealed in superheat temperatures over the saturated line attained by experiment as compared with theoretical values calculated in a macroscopic approximation. The revealed disagreement between theory and experiment is connected with the dependence of the properties of new-phase nuclei on their size.

  19. The novel fluid loss additive HTF-200C for oil field cementing%新型固井降失水剂HTF-200C

    Institute of Scientific and Technical Information of China (English)

    郭锦棠; 卢海川; 刘硕琼; 靳建州; 于永金

    2012-01-01

    The domestic fluid loss additives often have lower thermal stability and poor salt-tolerance and their comprehensive properties are not good enough. To solve the problems, a novel cement fluid loss additive HTF-200C. Which can resist high temperature and high salt content, was synthesized using the monomers of 2-acrylamido-2-methyl-propane sulphonic acid (AMPS), N, N-dimethyl acrylamide (DMAA) and a new compound with double carboxyl by the method of aqueous solution polymerization. The microstructural characterization and application performance of HTF-200C show that the polymer with the structure of all the monomers has an excellent thermal stability and strong salt tolerance, and can be used in 200 "C or in saturated brine. And the problem of the normal fluid loss additive being easy to hydrolyze due to high temperature can be solved with HTF-200C. What's more, it can also deal with the bulge of thickening curve in consistency test. The cement slurry prepared mainly by HTF-200C presents good comprehensive properties such as low filtration, high thermal stability, strong salt tolerance, rapid development of strength in low temperature, without far delayed solidification, short transit time during thickening process, and so on. The cementing job quality of Well Chengu 1-3 in the Liaohe Oilfield is excellent after it is used.%针对目前中国常规固井降失水剂抗温抗盐能力差、综合性能欠佳的问题,以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、N,N-二甲基丙烯酰胺(DMAA)、新型双羧基化合物为单体,采用水溶液自由基聚合的方法合成了耐盐、抗高温的共聚物型固井水泥降失水剂HTF-200C.HTF-200C微观结构表征和应用性能综合评价表明,各单体成功参与聚合,共聚物热稳定性良好;该降失水剂控失水耐温可达200℃,抗盐达饱和,可解决常规降失水剂高温下易水解、稠化实验“鼓包”等问题;以HTF-200C为主剂的水泥浆体系失水量低、抗盐耐温

  20. Superheater Corrosion In Biomass Boilers: Today's Science and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, William (Sandy) [SharpConsultant

    2011-12-01

    This report broadens a previous review of published literature on corrosion of recovery boiler superheater tube materials to consider the performance of candidate materials at temperatures near the deposit melting temperature in advanced boilers firing coal, wood-based fuels, and waste materials as well as in gas turbine environments. Discussions of corrosion mechanisms focus on the reactions in fly ash deposits and combustion gases that can give corrosive materials access to the surface of a superheater tube. Setting the steam temperature of a biomass boiler is a compromise between wasting fuel energy, risking pluggage that will shut the unit down, and creating conditions that will cause rapid corrosion on the superheater tubes and replacement expenses. The most important corrosive species in biomass superheater corrosion are chlorine compounds and the most corrosion resistant alloys are typically FeCrNi alloys containing 20-28% Cr. Although most of these materials contain many other additional additions, there is no coherent theory of the alloying required to resist the combination of high temperature salt deposits and flue gases that are found in biomass boiler superheaters that may cause degradation of superheater tubes. After depletion of chromium by chromate formation or chromic acid volatilization exceeds a critical amount, the protective scale gives way to a thick layer of Fe{sub 2}O{sub 3} over an unprotective (FeCrNi){sub 3}O{sub 4} spinel. This oxide is not protective and can be penetrated by chlorine species that cause further acceleration of the corrosion rate by a mechanism called active oxidation. Active oxidation, cited as the cause of most biomass superheater corrosion under chloride ash deposits, does not occur in the absence of these alkali salts when the chloride is present as HCl gas. Although a deposit is more corrosive at temperatures where it is molten than at temperatures where it is frozen, increasing superheater tube temperatures through

  1. Survey of the current state of knowledge of incipient boiling superheat in sodium

    Energy Technology Data Exchange (ETDEWEB)

    Greer, B.

    1979-01-01

    Superheat data obtained by various investigators indicate that many parameters affect this phenomenon. Controlling parameters appear to be inert gas concentration, oxide concentration, system pressure, pressure-temperature history, rate of temperature rise, heat flux, flow rate, operating time on the system, surface conditions, and radiation. Of these, the two believed most influential in controlling incipient boiling superheat are the inert gas concentration and oxide concentration. Experimental results for the heat flux and rate of temperature rise appear to be the most inconsistent.

  2. Analysis of damage of superheaters from steel 12Kh1MF in operation

    Science.gov (United States)

    Priymak, E. Yu.; Tryakina, N. Yu.; Gryzunov, V. I.; Sokolov, S. O.

    2013-05-01

    Main cases of damage of superheaters from steel 12Kh1MF due to disturbance of the process of production of the tubes and due to creep, thermal fatigue, and short-term superheating are considered. The methods of metallographic analysis and scanning electron microscopy are used to determine the special features of their microstructure and fracture surfaces. The results obtained are used to develop an algorithm for detecting the causes of damage in superheaters produced from heat-resistant pearlitic steels.

  3. Phase Identification and Internal Stress Analysis of Steamside Oxides on Plant Exposed Superheater Tubes

    OpenAIRE

    Pantleon, Karen; Montgomery, Melanie

    2012-01-01

    During long-term, high-temperature exposure of superheater tubes in thermal power plants, various oxides are formed on the inner side (steamside) of the tubes, and oxide spallation is a serious problem for the power plant industry. Most often, oxidation in a steam atmosphere is investigated in laboratory experiments just mimicking the actual conditions in the power plant for simplified samples. On real plant-exposed superheater tubes, the steamside oxides are solely investigated microscopical...

  4. ANALYSES OF HTF-48-12-20/24 (FEBRUARY, 2012) AND ARCHIVED HTF-E-05-021 TANK 48H SLURRY SAMPLES

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C.; Peters, T.

    2012-08-02

    Personnel characterized a Savannah River National Laboratory (SRNL) archived sample of Tank 48H slurry (HTF-E-05-021) in addition to the composite of samples HTF-48-12-20 and HTF-48-12-24, which were both retrieved in February 2012. The combined February 2012 sample is referred to as HTF-48-12-20/24 in this report. The results from these analyses are compared with Tank 48H samples analyzed in 2003, 2004, and 2005. This work supports the effort to demonstrate copper-catalyzed peroxide oxidation (CCPO) of organic content in this material. The principal findings with respect to the chemical and physical characteristics of the most recent sample are: (1) The measured potassium tetraphenylborate (KTPB) solid concentration is 1.76 wt %; (2) Titanium was in line with 2004 and 2005 slurry measurements at 897 mg/L, it represents 0.1535 {+-} 0.0012 wt % monosodium titanate (MST); (3) The measured insoluble solids content was 1.467 wt %; (4) The free hydroxide concentration in the Tank 48H filtrate sample (1.02 {+-} 0.02 M) is close to the Tank 48H limit (1.0 M); (5) Carbonate reported by total inorganic carbon (TIC, 1.39 {+-} 0.03 M) is more than double the concentrations measured in past (2003-2005) samples; (6) The soluble potassium content (measured at 286 {+-} 23 mg/L) in the filtrate is in line with all past measurements; and (7) The measured {sup 137}Cs concentration is 7.81E + 08 {+-} 3.9E + 07 dpm/mL of slurry (1.33 {+-} 5% Ci/gallon or 3.18E + 05 {+-} 5% curies of {sup 137}Cs in the tank) in the slurry which is in agreement with the 2005 report of 3.14E + 05 {+-} 1.5% curies of {sup 137}Cs in the tank. The filtrate {sup 137}Cs concentration is 2.57E + 07 {+-} 2.6E + 05 dpm/mL. This result is consistent with previous results. Significant analytical data are summarized in Table 1.

  5. Clinical pharmacodynamics of SDZ HTF 919, a new 5-HT4 receptor agonist, in a model of slow colonic transit.

    Science.gov (United States)

    Appel, S; Kumle, A; Meier, R

    1997-11-01

    To explore the pharmacodynamic effects of the new promotile agent SDZ HTF 919, a selective partial 5-HT4 receptor agonist, in healthy subjects. A pharmacodynamic model was applied to prolong colonic transit by dietary means. Subsequently, the effects of twice-daily multiple doses of SDZ HTF 919 (1, 5, 25, and 100 mg) were investigated in a randomized, double-blind, placebo-controlled parallel-group study with 12 subjects per dose level. The sequential design with three study periods of 7 days each included intake of a self-selected diet, a liquid formula diet with soluble fiber supplementation, and a fiber-supplemented diet together with either SDZ HTF 919 or placebo administration. Stool characteristics (frequency and consistency) and total colonic transit times (with use of radiopaque markers) were recorded in each study period. SDZ HTF 919 was well tolerated at all dose levels. The frequency of loose stool and headache increased with higher doses. After a fiber-supplemented diet intake, the median stool frequency decreased from 8 1/2-9 to 5-7 defecations per study period. SDZ HTF 919 in doses of 25 and 100 mg twice a day increased the stool frequency (p HTF 919 dose. A fiber-supplemented diet prolonged total colonic transit time in all groups by 45 hours on average. Twice-a-day administration of SDZ HTF 919 for 6 days in addition to a fiber-supplemented diet significantly shortened the total colonic transit time only at the 5 mg dose. The lack of effect at lower and higher SDZ HTF 919 doses suggests a biphasic dose-response relationship for total colonic transit time. The suitability of total colonic transit time measurements in healthy subjects as a surrogate marker should be confirmed by patient studies.

  6. Performance Improvement of Energy Storage System with nano-additivesin HTF

    Science.gov (United States)

    Beemkumar, N.; Karthikeyan, A.; Saravanakumar, B.; Jayaprabakar, J.

    2017-05-01

    This paper is intended to improve the heat transfer rate of thermal energy storage system with copper oxide (CuO) as nano-additivesin heat transfer fluid (HTF) by varying encapsulation materials. The experimentation is done with different encapsulating materials like copper, brass and aluminium. The results are analysed for their thermal performance characteristics during charging and discharging processes. D-Sorbitol and therminol-66 with CuO is used as PCM and HTF respectively. A comparison was made between the different encapsulations and it was found that copper encapsulation has higher efficient, storing and recovering energy. However, its high thermal conductivity promotes larger heat losses and its cost is also high on other side. So the economical use of encapsulation material is aluminium compared to other two materials.

  7. CFD analysis of supercritical CO2 used as HTF in a solar tower receiver

    Science.gov (United States)

    Roldán, M. I.; Fernández-Reche, J.

    2016-05-01

    The relative cost of a solar receiver can be minimized by the selection of an appropriate heat transfer fluid capable of achieving high receiver efficiencies. In a conventional central receiver system, the concentrated solar energy is transferred from the receiver tube walls to the heat transfer fluid (HTF), which passes through a heat exchanger to generate steam for a Rankine cycle. Thus, higher working fluid temperature is associated with greater efficiency in receiver and power cycle. Emerging receiver designs that can enable higher efficiencies using advanced power cycles, such as supercritical CO2 (s-CO2) closed-loop Brayton cycles, include direct heating of s-CO2 in tubular receiver designs capable of withstanding high internal fluid pressures (around 20 MPa) and temperatures (900 K). Due to the high pressures required and the presence of moving components installed in pipelines (ball-joints and/or flexible connections), the use of s-CO2 presents many technical challenges due to the compatibility of seal materials and fluid leakages of the moving connections. These problems are solved in solar tower systems because the receiver is fixed. In this regard, a preliminary analysis of a tubular receiver with s-CO2 as HTF has been developed using the design of a molten-salt receiver which was previously tested at Plataforma Solar de Almería (PSA). Therefore, a simplified CFD model has been carried out in this study in order to analyze the feasibility of s-CO2 as HTF in solar towers. Simulation results showed that the heat gained by s-CO2 was around 75% greater than the one captured by molten salts (fluid inlet temperature of 715 K), but at a pressure range of 7.5-9.7 MPa. Thus, the use of s-CO2 as HTF in solar tower receivers appears to be a promising alternative, taking into account both the operating conditions required and their maintenance cost.

  8. Identification of HTF (HER2 transcription factor) as an AP-2 (activator protein-2) transcription factor and contribution of the HTF binding site to ERBB2 gene overexpression.

    Science.gov (United States)

    Vernimmen, Douglas; Begon, Dominique; Salvador, Christophe; Gofflot, Stéphanie; Grooteclaes, Madeleine; Winkler, Rosita

    2003-02-15

    The ERBB2 gene is overexpressed in 30% of human breast cancers and this is correlated with poor prognosis. Overexpression of the ERBB2 gene is due to increased transcription and gene amplification. Our previous studies have identified a new cis element in the ERBB2 promoter which is involved in the gene's overexpression. This cis element, located 501 bp upstream from the main ERBB2 transcription initiation site, binds a transcription factor called HTF (HER2 transcription factor). We report here the identification of HTF as an AP-2 (activator protein-2) transcription factor. The new cis element is bound by AP-2 with high affinity, compared with a previously described AP-2 binding site located 284 bp downstream. Co-transfection of an AP-2alpha expression vector with a reporter vector containing the newly identified AP-2 binding site in front of a minimal ERBB2 promoter induced a dose-dependent increase in transcriptional activity. We examined the contribution of the new AP-2 binding site to ERBB2 overexpression. For this purpose we abolished the new and/or the previously described AP-2 binding sequence by site-directed mutagenesis. The results show that the two functional AP-2 sites in the first 700 bp of the ERBB2 promoter co-operate to achieve maximal transcriptional activity.

  9. Superheater corrosion in kraft recovery boilers; Korrosion hos oeverhettare i sodapannor. En oeversikt och diskussion

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, F. [AaF-IPK, Stockholm (Sweden)

    1997-02-01

    Corrosion seems to be the most essential factor limiting the life and the availability of kraft recovery boilers. The steam temperature from the kraft recovery boiler has, seen from the view of electricity production and steam turbine operation, traditionally been kept moderate, especially in comparison with steam data from normal utility power plants. So the corrosion of the superheaters has been more a limitation for the temperature of the steam produced by the boiler than a life length limitation. Both the pressure and the temperature of the steam are limited by corrosion. The temperature of the boiling water, and hence the pressure, is limited by the corrosion in the lower furnace. The temperature of the steam is limited by the corrosion in the superheater. Kraft boiler superheater corrosion is here governed not only by the boiler design, but more by the mill chemistry and boiler operation practice. This report discusses the formation and the properties of the deposits and their relation to boiler operation and the corrosion of the superheater tube material. We have tried to understand the corrosion in the kraft boiler superheaters better by comparing with the experience from the utility boilers. 86 refs, 79 figs

  10. Lifetime evaluation of superheater tubes exposed to steam oxidation, high temperature corrosion and creep

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, N. [Elsamprojekt A/S, Faelleskemikerne, Fredericia (Denmark); Hede Larsen, O.; Blum, R. [I/S Fynsvaerket, Faelleskemikerne, Odense (Denmark)

    1996-12-01

    Advanced fossil fired plants operating at high steam temperatures require careful design of the superheaters. The German TRD design code normally used in Denmark is not precise enough for the design of superheaters with long lifetimes. The authors have developed a computer program to be used in the evaluation of superheater tube lifetime based on input related to tube dimensions, material, pressure, steam temperature, mass flux, heat flux and estimated corrosion rates. The program is described in the paper. As far as practically feasible, the model seems to give a true picture of the reality. For superheaters exposed to high heat fluxes or low internal heat transfer coefficients as is the case for superheaters located in fluidized bed environments or radiant environments, the program has been extremely useful for evaluation of surface temperature, oxide formation and lifetime. The total uncertainty of the method is mainly influenced by the uncertainty of the determination of the corrosion rate. More precise models describing the corrosion rate as a function of tube surface temperature, fuel parameters and boiler parameters need to be developed. (au) 21 refs.

  11. Superheater Corrosion In Biomass Boilers: Today's Science and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, William (Sandy) [SharpConsultant

    2011-12-01

    This report broadens a previous review of published literature on corrosion of recovery boiler superheater tube materials to consider the performance of candidate materials at temperatures near the deposit melting temperature in advanced boilers firing coal, wood-based fuels, and waste materials as well as in gas turbine environments. Discussions of corrosion mechanisms focus on the reactions in fly ash deposits and combustion gases that can give corrosive materials access to the surface of a superheater tube. Setting the steam temperature of a biomass boiler is a compromise between wasting fuel energy, risking pluggage that will shut the unit down, and creating conditions that will cause rapid corrosion on the superheater tubes and replacement expenses. The most important corrosive species in biomass superheater corrosion are chlorine compounds and the most corrosion resistant alloys are typically FeCrNi alloys containing 20-28% Cr. Although most of these materials contain many other additional additions, there is no coherent theory of the alloying required to resist the combination of high temperature salt deposits and flue gases that are found in biomass boiler superheaters that may cause degradation of superheater tubes. After depletion of chromium by chromate formation or chromic acid volatilization exceeds a critical amount, the protective scale gives way to a thick layer of Fe{sub 2}O{sub 3} over an unprotective (FeCrNi){sub 3}O{sub 4} spinel. This oxide is not protective and can be penetrated by chlorine species that cause further acceleration of the corrosion rate by a mechanism called active oxidation. Active oxidation, cited as the cause of most biomass superheater corrosion under chloride ash deposits, does not occur in the absence of these alkali salts when the chloride is present as HCl gas. Although a deposit is more corrosive at temperatures where it is molten than at temperatures where it is frozen, increasing superheater tube temperatures through

  12. A comparison investigation of DNP-binding effects to HSA and HTF by spectroscopic and molecular modeling techniques.

    Science.gov (United States)

    Zolfagharzadeh, Mahboobeh; Pirouzi, Maliheh; Asoodeh, Ahmad; Saberi, Mohammad Reza; Chamani, Jamshidkhan

    2014-12-01

    This paper describes the interaction between 2,4-dinitrophenol (DNP) with the two drug carrier proteins - human serum albumin (HSA) and human holo transferrin (HTF). Hence, binding characteristics of DNP to HSA and HTF were analyzed by spectroscopic and molecular modeling techniques. Based on results obtained from fluorescence spectroscopy, DNP had a strong ability to quench the intrinsic fluorescence of HSA and HTF through a static quenching procedure. The binding constant and the number of binding sites were calculated as 2.3 × 10(11) M(-1) and .98 for HSA, and 1.7 × 10(11) M(-1) and 1.06 for HTF, respectively. In addition, synchronous fluorescence results showed that the microenvironment of Trp had a slight tendency of increasing its hydrophobicity, whereas the microenvironment of the Tyr residues of HSA did not change and that of HTF showed a significant trend (red shift of about 4 nm) of an increase in polarity. The distance between donor and acceptor was obtained by the Förster energy according to fluorescence resonance energy transfer, and was found to be 3.99 and 3.72 nm for HSA and HTF, respectively. The critical induced aggregation concentration (CCIAC) of the drug on both proteins was determined and confirmed by an inflection point of the zeta potential behavior. Circular dichroism data revealed that the presence of DNP caused a decrease of the α-helical content of HSA and HTF, and induced a remarkable mild denaturation of both proteins. The molecular modeling data confirmed our experimental results. This study is deemed useful for determining drug dosage.

  13. A randomized control comparison study of culture media (HTF versus P1) for human in vitro fertilization.

    Science.gov (United States)

    Artini, Paolo G; Valentino, Valeria; Cela, Vito; Cristello, Francesca; Vitè, Alessandra; Genazzani, Andrea R

    2004-10-15

    It is now widely accepted that increasing the number of replacement embryos (>3 embryos per embryo transfer [ET]) is associated with an increased risk of multiple pregnancies. While embryo reduction is often proposed when there is a high risk of multiple pregnancies, it is a difficult decision for the couple. For this reason, different studies have focused on single embryo transfer, more precisely blastocyst transfer. The aim of the study is to confirm that phosphate-free culture media can be used to generate greater quality embryos. We carried out a study to compare the efficacy of human tubal fluid (HTF) versus preimplantation stage one (P1) as culture media for assisted reproductive therapy (ART). In 109 nonselected patients, we obtained an embryo fertilization rate with HTF and P1 culture media of 58.6 and 62.5% (P = 0.003), respectively. After 48 and 72 h, the morphology was similar for both P1 and HTF embryos in most patients. However, in the same patients, when HTF embryo quality was low (15.4%), P1 embryo quality was significantly higher 68.7% (P = 0.002). Some embryos were transferred at 48 h and some at 72 h after retrieval, in a randomized manner. We transferred a maximum of up to three embryos per ET. The implantation rate was significantly different; at 48 h, it was 6.8 and 12.2% for HTF and P1, respectively (P = 0.02). The pregnancy rate was 17.1% for HTF embryos and 23.7% for P1 embryos (P = 0.02). Therefore, we observed a significant difference between P1 and HTF in the fertilization rate, in embryo quality, in implantation rate and in pregnancy rate. But the most important difference between this study and others is that every patient was the control of herself, so we eliminated every variable.

  14. Phase Identification and Internal Stress Analysis of Steamside Oxides on Plant Exposed Superheater Tubes

    DEFF Research Database (Denmark)

    Pantleon, Karen; Montgomery, Melanie

    2012-01-01

    During long-term, high-temperature exposure of superheater tubes in thermal power plants, various oxides are formed on the inner side (steamside) of the tubes, and oxide spallation is a serious problem for the power plant industry. Most often, oxidation in a steam atmosphere is investigated in la...... typically applied for superheaters, ferritic-martensitic X20CrMoV12-1 and lean austenitic stainless steel TP347H, respectively, are revealed by X-ray diffraction.......-exposed superheater tubes was proven in the current work; the challenges for depth-resolved phase analysis and phase-specific residual stress analysis at the inner side of the tubes with concave surface curvature are discussed. Essential differences between the steamside oxides formed on two different steels...

  15. Single Temperature Sensor Superheat Control Using a Novel Maximum Slope-seeking Method

    DEFF Research Database (Denmark)

    Vinther, Kasper; Rasmussen, Henrik; Izadi-Zamanabadi, Roozbeh;

    2013-01-01

    Superheating of refrigerant in the evaporator is an important aspect of safe operation of refrigeration systems. The level of superheat is typically controlled by adjusting the flow of refrigerant using an electronic expansion valve, where the superheat is calculated using measurements from...... a pressure and a temperature sensor. In this paper we show, through extensive testing, that the superheat or filling of the evaporator can actually be controlled using only a single temperature sensor. This can either reduce commissioning costs by lowering the necessary amount of sensors or add fault...... tolerance in existing systems if a sensor fails (e.g. pressure sensor). The solution is based on a novel maximum slope-seeking control method, where a perturbation signal is added to the valve opening degree, which gives additional information about the system for control purposes. Furthermore, the method...

  16. Predictive functional control of an expansion valve for minimizing the superheat of an evaporator

    Energy Technology Data Exchange (ETDEWEB)

    Fallahsohi, H.; Place, S. [EDF R and D, Av. des Renardieres, 77818 Moret-sur-Loing (France); Changenet, C. [Universite de Lyon, ECAM, Laboratoire d' Energetique, 40 Montee Saint-Barthelemy, 69321 Lyon cedex 05 (France); Ligeret, C. [Schneider-Electric, 37 Quai Paul Louis Merlin, 38050 Grenoble (France); Lin-Shi, X. [Universite de Lyon, INSA-Lyon, Ampere, CNRS UMR5005, 24 avenue Jean Capelle, 69621 Villeurbanne cedex (France)

    2010-03-15

    In a previous paper, a Predictive Functional Control (PFC) method was proposed to control the evaporator superheat with an electronic expansion valve. It has been shown that superheat may be more accurately controlled by PFC than the conventional Proportional-Integral-Derivative (PID) control. In this paper, the proposed methodology is extended to regulate the condensing pressure. In order to study the influence of this control method on the Coefficient of Performance (COP), experiments are conducted on a refrigerating machine by changing the cooling capacity from 120 to 30 kW. As PFC improves disturbance rejection compared to a PID control, it is possible to reduce the superheat setting value and to prevent any unevaporated refrigerant liquid from reaching the compressor. As a consequence the use of PFC leads to an increase of COP which depends on operating conditions. (author)

  17. Coabsorbent and thermal recovery compression heat pumping technologies

    CERN Document Server

    Staicovici, Mihail-Dan

    2014-01-01

    This book introduces two of the most exciting heat pumping technologies, the coabsorbent and the thermal recovery (mechanical vapor) compression, characterized by a high potential in primary energy savings and environmental protection. New cycles with potential applications of nontruncated, truncated, hybrid truncated, and multi-effect coabsorbent types are introduced in this work.   Thermal-to-work recovery compression (TWRC) is the first of two particular methods explored here, including how superheat is converted into work, which diminishes the compressor work input. In the second method, thermal-to-thermal recovery compression (TTRC), the superheat is converted into useful cooling and/or heating, and added to the cycle output effect via the coabsorbent technology. These and other methods of discharge gas superheat recovery are analyzed for single-, two-, three-, and multi-stage compression cooling and heating, ammonia and ammonia-water cycles, and the effectiveness results are given.  The author presen...

  18. Faecalibacterium prausnitzii Strain HTF-F and Its Extracellular Polymeric Matrix Attenuate Clinical Parameters in DSS-Induced Colitis.

    Science.gov (United States)

    Rossi, Oriana; Khan, M Tanweer; Schwarzer, Martin; Hudcovic, Tomas; Srutkova, Dagmar; Duncan, Sylvia H; Stolte, Ellen H; Kozakova, Hana; Flint, Harry J; Samsom, Janneke N; Harmsen, Hermie J M; Wells, Jerry M

    2015-01-01

    A decrease in the abundance and biodiversity of intestinal bacteria within the Firmicutes phylum has been associated with inflammatory bowel disease (IBD). In particular, the anti-inflammatory bacterium Faecalibacterium prausnitzii, member of the Firmicutes phylum and one of the most abundant species in healthy human colon, is underrepresented in the microbiota of IBD patients. The aim of this study was to investigate the immunomodulatory properties of F. prausnitzii strain A2-165, the biofilm forming strain HTF-F and the extracellular polymeric matrix (EPM) isolated from strain HTF-F. For this purpose, the immunomodulatory properties of the F. prausnitzii strains and the EPM were studied in vitro using human monocyte-derived dendritic cells. Then, the capacity of the F. prausnitzii strains and the EPM of HTF-F to suppress inflammation was assessed in vivo in the mouse dextran sodium sulphate (DSS) colitis model. The F. prausnitzii strains and the EPM had anti-inflammatory effects on the clinical parameters measured in the DSS model but with different efficacy. The immunomodulatory effects of the EPM were mediated through the TLR2-dependent modulation of IL-12 and IL-10 cytokine production in antigen presenting cells, suggesting that it contributes to the anti-inflammatory potency of F. prausnitzii HTF-F. The results show that F. prausnitzii HTF-F and its EPM may have a therapeutic use in IBD.

  19. Faecalibacterium prausnitzii Strain HTF-F and Its Extracellular Polymeric Matrix Attenuate Clinical Parameters in DSS-Induced Colitis.

    Directory of Open Access Journals (Sweden)

    Oriana Rossi

    Full Text Available A decrease in the abundance and biodiversity of intestinal bacteria within the Firmicutes phylum has been associated with inflammatory bowel disease (IBD. In particular, the anti-inflammatory bacterium Faecalibacterium prausnitzii, member of the Firmicutes phylum and one of the most abundant species in healthy human colon, is underrepresented in the microbiota of IBD patients. The aim of this study was to investigate the immunomodulatory properties of F. prausnitzii strain A2-165, the biofilm forming strain HTF-F and the extracellular polymeric matrix (EPM isolated from strain HTF-F. For this purpose, the immunomodulatory properties of the F. prausnitzii strains and the EPM were studied in vitro using human monocyte-derived dendritic cells. Then, the capacity of the F. prausnitzii strains and the EPM of HTF-F to suppress inflammation was assessed in vivo in the mouse dextran sodium sulphate (DSS colitis model. The F. prausnitzii strains and the EPM had anti-inflammatory effects on the clinical parameters measured in the DSS model but with different efficacy. The immunomodulatory effects of the EPM were mediated through the TLR2-dependent modulation of IL-12 and IL-10 cytokine production in antigen presenting cells, suggesting that it contributes to the anti-inflammatory potency of F. prausnitzii HTF-F. The results show that F. prausnitzii HTF-F and its EPM may have a therapeutic use in IBD.

  20. Evaporator Superheat Control With One Temperature Sensor Using Qualitative System Knowledge

    DEFF Research Database (Denmark)

    Vinther, Kasper; Hillerup Lyhne, Casper; Baasch Sørensen, Erik;

    2012-01-01

    This paper proposes a novel method for superheat control using only a single temperature sensor at the outlet of the evaporator, while eliminating the need for a pressure sensor. An inner loop controls the outlet temperature and an outer control loop provides a reference set point, which is based...

  1. Superheater fouling in a BFB boiler firing wood-based fuel blends

    NARCIS (Netherlands)

    Stam, A.F.; Haasnoot, K.; Brem, G.

    2014-01-01

    Four different fuel blends have been fired in a 28 MWel BFB. Wood pellets (test 0) were not problematic for about ten years, contrary to a mixture of demolition wood, wood cuttings, compost overflow, paper sludge and roadside grass (test 1) which caused excessive fouling at a superheater bundle afte

  2. Further investigations of plasma armature performance in the Culham Laboratory HTF rail launcher

    Science.gov (United States)

    Herring, N.; Spikings, C. R.; Oxley, C. M.; Beacham, J. R.; Putley, D.

    1993-01-01

    This paper presents the results from an experimental investigation of plasma armature behavior in the Culham Laboratory HTF rail launcher. The object of this work was to gain further insight into the conditions which lead to the formation of secondary plasma arcs in the rail launcher. The railgun was operated with a 1 cm square bore formed from glass reinforced epoxy insulators and either stainless steel or copper rails. A 1 MJ, 8 kV capacitor bank was used as the power supply; this was arranged in five 200 kJ modules. The modules were sequentially fired, to produce a current waveform approximating to a linear ramp in the railgun. B-dot probes were used to measure the behavior of the plasma armatures in the launcher. A number of calibration checks were performed to assess the quality of the B-dot probe measurements, with regard to both spatial resolution and rail current measurement. Experimental results were obtained with projectile muzzle velocities ranging from 1.5 km/s to 3.0 km/s, two free arc shots also occurred during the test series. The results show that the launcher performed much better with copper rails than with stainless steel rails. The results also show that the glass epoxy insulators performed much better than the acetyl copolymer material previously used in HTF.

  3. Superheater corrosion in combustion of biofuels - a status; Oeverhettarkorrosion i bioeldade anlaeggningar - status

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Pamela [SwedPower AB, Stockholm (Sweden); Kjoerk, Anders [S.E.P. Scandinavian Energy Project AB, Stockholm (Sweden); Ljung, Per [Vattenfall Utveckling AB, Stockholm (Sweden); Nystroem, Olle; Skog, Erik [Sycon Energikonsult AB, Malmoe (Sweden)

    2000-06-01

    In this report a survey of the status with regard to the current understanding of what is causing superheater corrosion in biofueled CHP boilers is made together with an assessment of where knowledge and resources need to be strengthened. A division in three areas has been made: * Type of units/combustion, * Biofuels/combustion, and * Superheater materials. As yet, the knowledge and the results gained remain to be amalgamated in an effort to grasp the complex casual connections and course of events leading to corrosion. So far there are indications of important underlying factors and causes and it is also possible to make qualitative statements about possible mechanisms: * With high enough superheater surface temperatures (due to high steam temperatures) low-melting point alkali compounds caught in the deposit will start to melt. * Potassium chloride has a distinct and crucial roll with regard to the percentage of fluid in ash and deposits. This in turn is decisive for transport of corrosive elements, e.g. chlorine, between the deposit and the metal(oxide). * Poor combustion with e.g. plume formation and reducing atmosphere. Staged combustion for NO{sub x}-reduction, fine particle fractions giving rise to uncontrolled suspension combustion and short retention times are factors that contribute to the problem, not least by moving combustion up into the superheater area of the boiler. * The superheater position in the upper part of the furnace, where it is exposed to flame and particle radiation may increase the surface temperature of the deposit by several tens of degrees, which may be vital. A position in radiation protected areas indicates decreased corrosion(rates). * Conventional superheater materials made from (ferritic) low chromium steels originally designed for use in coal combustion are not adequate. Test results indicate that more highly alloyed (austenitic) materials that are used in waste-fired plants will be necessary. * Test results have revealed

  4. Non-contact Measurement of Remaining Thickness of Corroding Superheater Tubes. Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Borggreen, Kjeld; Storesund, Jan

    2007-12-15

    The Electro Magnetic Acoustic Transducer (EMAT) is a contactless thickness gauge for detection of corrosion on superheater tubes; it candidates as substitute for conventional manually operated contact UT transducers. It is the aim of the project to demonstrate the usefulness of two simple EMAT systems, Panametrics and Sonatest, for fast and reliable tube thickness inspections in difficult-to-access superheater sections. The present Phase 2 of the project involves testing of the systems on real compact superheaters in remote operation with the help of a mechanical manipulator designed and built for the purpose. The results are the following: - Both EMAT systems work well when tested in the field during handheld operation on tubes with a moderate thick layer of corrosion products and ash. The practical obtainable speed of cross-panel inspection of easily accessible panels is approximately 6 tubes per minute (6 thickness readings per minute). - The Sonatest system works well when tested in the field during remote operation on heavily corroded superheater tubes with thick ash layer. The Panametrics system was not found suitable for this type of field work. - The mechanical manipulator works well for cross-panel inspection of difficult-to-access superheater sections independent of the tube dimensions and the free space between the panels. In its present design it needs few improvements. - The practical obtainable speed of cross-panel inspection is 3 tubes per minute (3 thickness readings per minute). This speed is limited by the detection rate of the EMAT system and not by the travelling speed of the probe. - Scanning of tubes along their axis was never attempted, because the EMAT instruments were not capable of collecting data coming as a continuous stream. - It cannot be judged from visual alone and hardly from the service data, if a tube or a panel can be inspected by the magnetostrictive EMAT method or not. - The main contribution to failure of the EMAT inspection

  5. Characterization of the tank 51 alternate reductant sludge batch 9 slurry sample (HTF-51-15-130)

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-01

    Tank 51 slurry sample HTF-51-15-130 was collected following sludge washing at the Tank Farm. The sample was received at SRNL and then characterized in preparation for qualification of the alternate reductant Sludge Batch 9 (SB9) flowsheet. In this characterization, densities, solids distribution, elemental constituents, anionic constituents, carbon content, and select radioisotopes were quantified.

  6. Influence of Superheated Steam Temperature Regulation Quality on Service Life of Boiler Steam Super-Heater Metal

    Directory of Open Access Journals (Sweden)

    G. T. Kulakov

    2009-01-01

    Full Text Available The paper investigates influence of change in quality of superheated steam temperature regulations on service life of super-heater metal. А dependence between metal service life and dispersion value for different steel grades has been determined in the paper. Numerical values pertaining to increase of super-heater metal service life in case of transferring from manual regulation to standard system of automatic regulation (SAR have been determined and in case of transferring from standard SAR to improved SAR. The analysis of tabular data and plotted dependencies makes it possible to conclude that any change in conditions of convection super-heater metal work due to better quality of the regulation leads to essential increase of time period which is left till the completion of the service life of a super-heater heating surface.

  7. Comparison of the binding behavior of FCCP with HSA and HTF as determined by spectroscopic and molecular modeling techniques.

    Science.gov (United States)

    Moghaddam, Maryam Mahmoodian; Pirouzi, Malihe; Saberi, Mohammad Reza; Chamani, Jamshidkhan

    2014-06-01

    The interaction of carbonylcyanide p-(trifluoromethoxy) phenylhydrazone (FCCP) with human serum albumin (HSA) and human transferrin (HTF) was investigated using multiple spectroscopy, molecular modeling, zeta-potential and conductometry measurements of aqueous solutions at pH 7.4. The fluorescence, UV/vis and polarization fluorescence spectroscopy data disclosed that the drug-protein complex formation occurred through a remarkable static quenching. Based on the fluorescence quenching, two sets of binding sites with distinct affinities for FCCP existed in the two proteins. Steady-state and polarization fluorescence analysis showed that there were more affinities between FCCP and HSA than HTF. Far UV-CD and synchronous fluorescence studies indicated that FCCP induced more structural changes on HSA. The resonance light scattering (RLS) and zeta-potential measurements suggested that HTF had a greater resistance to drug aggregation, whereas conductometry measurements expressed the presence of free ions improving the resistance of HSA to aggregation. Thermodynamic measurements implied that a combination of electrostatic and hydrophobic forces was involved in the interaction between FCCP with both proteins. The phase diagram plots indicated that the presence of second binding site on HSA and HTF was due to the existence of intermediate structures. Site marker competitive experiments demonstrated that FCCP had two distinct binding sites in HSA which were located in sub-domains IIA and IIIA and one binding site in the C-lobe of HTF as confirmed by molecular modeling. The obtained results suggested that both proteins could act as drug carriers, but that the HSA potentially had a higher capacity for delivering FCCP to cancerous tissues. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Stress and integrity analysis of steam superheater tubes of a high pressure boiler

    Directory of Open Access Journals (Sweden)

    Neves Daniel Leite Cypriano

    2004-01-01

    Full Text Available Sources that can lead to deterioration of steam superheater tubes of a high pressure boiler were studied by a stress analysis, focused on internal pressure and temperature experienced by the material at real operating conditions. Loss of flame control, internal deposits and unexpected peak charge are factors that generate loads above the design limit of tube materials, which can be subjected to strain, buckling, cracks and finally rupture in service. To evaluate integrity and dependability of these components, the microstructure of selected samples along the superheater was studied by optical microscopy. Associated with this analysis, dimensional inspection, nondestructive testing, hardness measurement and deposit examination were made to determine the resultant material condition after twenty three years of operation.

  9. Superheater corrosion in biomass-fired power plants: Investigation of Welds

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Carlsen, B; Biede, O

    2002-01-01

    condense on superheater components. This gives rise to specific corrosion problems not previously encountered in coal-fired power plants. The type of corrosion attack can be directly ascribed to the composition of the deposit and the metal surface temperature. A test superheater was built into the straw......-fired Masnedø combined heat and power (CHP) plant to investigate corrosion at temperatures higher than that of the actual plant. The highest steam temperature investigated was 570°C. Various alloys of 12-22% chromium content were welded into this test loop. Their corrosion rates were similar and increased...... which had a similar composition to the tubes did not incur this type of corrosion. It is suggested that high temperature galvanic corrosion occurs due to the formation of molten chloride mixtures which serve as the electrolyte....

  10. Superheater corrosion in biomass-fired power plants: Investigation of Welds

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Carlsen, B; Biede, O

    2002-01-01

    condense on superheater components. This gives rise to specific corrosion problems not previously encountered in coal-fired power plants. The type of corrosion attack can be directly ascribed to the composition of the deposit and the metal surface temperature. A test superheater was built into the straw......-fired Masnedø combined heat and power (CHP) plant to investigate corrosion at temperatures higher than that of the actual plant. The highest steam temperature investigated was 570°C. Various alloys of 12-22% chromium content were welded into this test loop. Their corrosion rates were similar and increased...... with temperature. The mechanism of attack was grain boundary attack as a precursor to selective chromium depletion of the alloy. In addition welds coupling various tubes sections were also investigated. It was seen that there was preferential attack around those welds that had a high nickel content. The welds...

  11. Nonlinear FOPDT Model Identification for the Superheat Dynamic in a Refrigeration System

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Sun, Zhen; Andersen, Casper

    2011-01-01

    An on-line nonlinear FOPDT system identification method is proposed and applied to model the superheat dynamic in a supermarket refrigeration system. The considered nonlinear FOPDT model is an extension of the standard FOPDT model by means that its parameters are time dependent. After......-dependent parameters. The proposed method is firstly tested through a number of numerical examples, and then applied to model the superheat dynamic in a supermarket refrigeration system based on experimental data. As shown in these studies, the proposed method is quite promising in terms of reasonable accuracy, large...... the considered system is discretized, the nonlinear FOPDT identification problem is formulated as a Mixed Integer Non-Linear Programming problem, and then an identification algorithm is proposed by combining the Branch-and-Bound method and Least Square technique, in order to on-line identify these time...

  12. A new method for estimating heat flux in superheater and reheater tubes

    Energy Technology Data Exchange (ETDEWEB)

    Purbolaksono, J. [Department of Mechanical Engineering, Universiti Tenaga Nasional, km 7 Jalan Kajang-Puchong, Kajang 43009, Selangor (Malaysia)], E-mail: judha@uniten.edu.my; Khinani, A.; Rashid, A.Z.; Ali, A.A. [Department of Mechanical Engineering, Universiti Tenaga Nasional, km 7 Jalan Kajang-Puchong, Kajang 43009, Selangor (Malaysia); Ahmad, J. [Kapar Energy Ventures Sdn Bhd, Jalan Tok Muda, Kapar 42200, Selangor (Malaysia); Nordin, N.F. [TNB Research Sdn Bhd, No. 1 Lorong Air Hitam, Kajang 43000, Selangor (Malaysia)

    2009-10-15

    In this paper a procedure on how to estimate the heat flux in superheater and reheater tubes utilizing the empirical formula and the finite element modeling is proposed. An iterative procedure consisting of empirical formulae and numerical simulation is used to determine heat flux as both temperature and scale thickness increase over period of time. Estimation results of the heat flux over period of time for two different design temperatures of the steam and different heat transfer parameters are presented.

  13. Influence of the superheat associated to a semihermetic compressor of a transcritical CO2 refrigeration plant

    OpenAIRE

    Sánchez, D.; Torrella, E.; Cabello,R; Llopis, R.

    2009-01-01

    Abstract This work evaluates, from an energetic point of view, the effects of the superheat caused in the refrigerant by the electric motor cooling (SHSC) in a semihermetic compressor installed in an experimental refrigerating plant, which operates with CO2 as the working fluid in transcritical conditions. The analysis is based on 84 experimental tests which cover a wide range of operating conditions of the plant: three evaporating levels (0, -10, -17 ?C) at four compressor speeds ...

  14. Premature failure of dissimilar metal weld joint at intermediate temperature superheater tube

    OpenAIRE

    Al Hajri, Mohammed; Anees U. Malik; MEROUFEL, Abdelkader; Al-Muaili, Fahd

    2015-01-01

    Dissimilar metal weld (DMW) joint between alloyed steel (AS) and stainless steel (SS) failed at one of intermediate temperature superheater (ITSH) tube in steam/power generation plant boiler. The premature failure was detected after a relatively short time of operation (8 years) where the crack propagated circumferentially from AS side through the ITSH tube. Apart from physical examination, microstructural studies based on optical microscopy, SEM and EDX analysis were performed. The results o...

  15. Effects of Liquid Superheat on Droplet Disruption and Vaporization in Supersonic Conditions

    Science.gov (United States)

    2007-11-02

    studies.’ .- 3 Model Structure The limiting approximation of model is that the droplets are modeled as non - evaporating , rigid spheres. The reason for...of the test fluids vary only slightly, and ethanol has the median density of the three fluids . The Newtonian equation for change in velocity due to... Evaporation at the Superheat Limit," International Journal of Heat and Mass Transfer, Vol. 31, No. 8, 1988, pp. 1687-1988. 14Ried, Robert C

  16. Effect of the melt superheat on equiaxed solidification of Al-20 wt% Cu alloy investigated by in situ synchrotron radiography

    Science.gov (United States)

    Luo, Shifeng; Yang, Guangyu; Xiao, Lei; Huang, Wanxia; Yuan, Qingxi; Jie, Wanqi

    2017-10-01

    Effect of the melt superheat on equiaxed solidification of Al-20 wt% Cu alloy was investigated by in-situ synchrotron radiography at Beijing Synchrotron Radiation Facility. For comparison, the corresponding DSC analysis was also conducted. It was found that the grain size decreased with increasing the melt superheat. The relationship between the final mean grain size and the melt superheat can be expressed as: d = 4919.3 × ΔT-0.33 . During solidification, the mean grain size increased sharply in the first 70 s, then reached the final grain size gradually. Furthermore, with increasing the melt superheat, the mean nucleation rate increased, which can be attributed to the fact that increasing the melt superheat led to an increase in nucleation undercooling, and the growth rate and the duration of free growth stage decreased. As the melt superheat increased from 100 °C to 160 °C, the mean nucleation rate increased by 78.2% while the mean growth rate only decreased by 19.3%, which indicated that the high mean nucleation rate and the consequent low mean growth rate may be the real reasons for grain refinement. The increased nucleation density caused earlier growth deceleration due to solutal impingement effects.

  17. Heat-pump-assisted dryer: Pt. 1; Mathematical model

    Energy Technology Data Exchange (ETDEWEB)

    Pendyala, V.R.; Devotta, S.; Patwardhan, V.S. (National Chemical Lab., Poona (India))

    1990-07-01

    A mathematical model for an integrated heat-pump-assisted dryer has been developed. The dryer has been modelled considering the heat transfer and simultaneous heat and mass transfer zones. The heat-pump heat exchangers have been modelled by writing the enthalpy balance for differential lengths considering the various zones on the air and working-fluid sides. The compressor has been described by the polytropic compression equation. The model has been used for simulating an existing system using R11 to study the effect of approach velocity of air to the evaporator and of the suction superheat on the specific energy consumption of the heat pump assisted dryer. (author).

  18. Soft Sensor for Oxide Scales on the Steam Side of Superheater Tubes under Uneven Circumferential Load

    Directory of Open Access Journals (Sweden)

    Qing Wei Li

    2015-01-01

    Full Text Available A soft sensor for oxide scales on the steam side of superheater tubes of utility boiler under uneven circumferential loading is proposed for the first time. First finite volume method is employed to simulate oxide scales growth temperature on the steam side of superheater tube. Then appropriate time and spatial intervals are selected to calculate oxide scales thickness along the circumferential direction. On the basis of the oxide scale thickness, the stress of oxide scales is calculated by the finite element method. At last, the oxide scale thickness and stress sensors are established on support vector machine (SMV optimized by particle swarm optimization (PSO with time and circumferential angles as inputs and oxide scale thickness and stress as outputs. Temperature and stress calculation methods are validated by the operation data and experimental data, respectively. The soft sensor is applied to the superheater tubes of some power plant. Results show that the soft sensor can give enough accurate results for oxide scale thickness and stress in reasonable time. The forecasting model provides a convenient way for the research of the oxide scale failure.

  19. Microstructural characteristics of in situ Mg2Si/Al-Si composite by low superheat pouring

    Directory of Open Access Journals (Sweden)

    Wu Xiaofeng

    2013-09-01

    Full Text Available To control the morphology and size of the primary and eutectic Mg2Si phases in in situ Mg2Si/Al-Si composite and achieve a feasible and reliable technique to produce appropriate feedstock for the thixo-casting and rheo-casting of this type of material, three Al-Si matrix composites reinforced by 5wt.%, 9wt.% and 17wt.% Mg2Si with hypoeutectic, eutectic and hypereutectic compositions were prepared by the low superheat pouring (LSP process. The effects of the pouring temperature (superheat on the morphology and size distribution of primary phases (primary α-Al and Mg2Si, binary (α-Al + Mg2Si eutectic cell and eutectic Mg2Si were investigated. The experimental results show that low pouring temperature (superheat not only refines the grain structure of the primary α-Al and binary (α-Al + Mg2Si eutectic cell in three composites and promotes the formation of more non-dendritic structural semi-solid metal (SSM slurry of these phases; but also refines the primary and eutectic Mg2Si phases, which seems to be attributed to the creation of an ideal condition for the nucleation and the acquisition of a high survival of nuclei caused by the LSP process.

  20. Characterization Of The As-Received Sludge Batch 9 Qualification Sample (Htf-51-15-81)

    Energy Technology Data Exchange (ETDEWEB)

    Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-30

    Savannah River National Laboratory (SRNL) personnel have been requested to qualify the next sludge batch (Sludge Batch 9 – SB9) for processing at the Defense Waste Processing Facility (DWPF). To accomplish this task, Savannah River Remediation (SRR) has sent SRNL a 3-L slurried sample of Tank 51H (HTF-51-15-81) to be characterized, washed, and then used in a lab-scale demonstration of the DWPF flowsheet (potentially after combining with Tank 40H sludge). This report documents the first steps of the qualification process – characterization of the as-received Tank 51H qualification sample. These results will be used to support a reprojection of SB9 by SRR from which final Tank 51H washing, frit development, and Chemical Processing Cell (CPC) activities will be based.

  1. Influence of embryo culture medium (G5 and HTF) on pregnancy and perinatal outcome after IVF: a multicenter RCT.

    Science.gov (United States)

    Kleijkers, Sander H M; Mantikou, Eleni; Slappendel, Els; Consten, Dimitri; van Echten-Arends, Jannie; Wetzels, Alex M; van Wely, Madelon; Smits, Luc J M; van Montfoort, Aafke P A; Repping, Sjoerd; Dumoulin, John C M; Mastenbroek, Sebastiaan

    2016-10-01

    Does embryo culture medium influence pregnancy and perinatal outcome in IVF? Embryo culture media used in IVF affect treatment efficacy and the birthweight of newborns. A wide variety of culture media for human preimplantation embryos in IVF/ICSI treatments currently exists. It is unknown which medium is best in terms of clinical outcomes. Furthermore, it has been suggested that the culture medium used for the in vitro culture of embryos affects birthweight, but this has never been demonstrated by large randomized trials. We conducted a multicenter, double-blind RCT comparing the use of HTF and G5 embryo culture media in IVF. Between July 2010 and May 2012, 836 couples (419 in the HTF group and 417 in the G5 group) were included. The allocated medium (1:1 allocation) was used in all treatment cycles a couple received within 1 year after randomization, including possible transfers with frozen-thawed embryos. The primary outcome was live birth rate. Couples that were scheduled for an IVF or an ICSI treatment at one of the six participating centers in the Netherlands or their affiliated clinics. The live birth rate was higher, albeit nonsignificantly, in couples assigned to G5 than in couples assigned to HTF (44.1% (184/417) versus 37.9% (159/419); RR: 1.2; 95% confidence interval (CI): 0.99-1.37; P = 0.08). Number of utilizable embryos per cycle (2.8 ± 2.3 versus 2.3 ± 1.8; P HTF. Of the 383 live born children in this trial, birthweight data from 380 children (300 singletons (G5: 163, HTF: 137) and 80 twin children (G5: 38, HTF: 42)) were retrieved. Birthweight was significantly lower in the G5 group compared with the HTF group, with a mean difference of 158 g (95% CI: 42-275 g; P = 0.008). More singletons were born preterm in the G5 group (8.6% (14/163) versus 2.2% (3/137), but singleton birthweight adjusted for gestational age and gender (z-score) was also lower in the G5 than in the HTF group (-0.13 ± 0.08 versus 0.17 ± 0.08; P = 0.008). This study was powered

  2. A conserved homeobox transcription factor Htf1 is required for phialide development and conidiogenesis in Fusarium species.

    Directory of Open Access Journals (Sweden)

    Wenhui Zheng

    Full Text Available Conidia are primary means of asexual reproduction and dispersal in a variety of pathogenic fungi, and it is widely recognized that they play a critical role in animal and plant disease epidemics. However, genetic mechanisms associated with conidiogenesis are complex and remain largely undefined in numerous pathogenic fungi. We previously showed that Htf1, a homeobox transcription factor, is required for conidiogenesis in the rice pathogen Magnaporthe oryzae. In this study, our aim was to characterize how Htf1 homolog regulates common and also distinctive conidiogenesis in three key Fusarium pathogens: F. graminearm, F. verticillioides, and F. oxysporum. When compared to wild-type progenitors, the gene-deletion mutants in Fusarium species failed to form conventional phialides. Rather, they formed clusters of aberrant phialides that resembled elongated hyphae segments, and it is conceivable that this led to the obstruction of conidiation in phialides. We also observed that mutants, as well as wild-type Fusaria, can initiate alternative macroconidia production directly from hyphae through budding-like mechanism albeit at low frequencies. Microscopic observations led us to conclude that proper basal cell division and subsequent foot cell development of macroconidia were negatively impacted in the mutants. In F. verticillioides and F. oxysporum, mutants exhibited a 2- to 5- microconidia complex at the apex of monophialides resulting in a floral petal-like shape. Also, prototypical microconidia chains were absent in F. verticillioides mutants. F. graminearum and F. verticillioides mutants were complemented by introducing its native HTF1 gene or homologs from other Fusarium species. These results suggest that Fusarium Htf1 is functionally conserved homeobox transcription factor that regulates phialide development and conidiogenesis via distinct signaling pathways yet to be characterized in fungi.

  3. Superheater corrosion in combustion of biofuels - a status; Oeverhettarkorrosion i bioeldade anlaeggningar - status

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Pamela [SwedPower AB, Stockholm (Sweden); Kjoerk, Anders [S.E.P. Scandinavian Energy Project AB, Stockholm (Sweden); Ljung, Per [Vattenfall Utveckling AB, Stockholm (Sweden); Nystroem, Olle; Skog, Erik [Sycon Energikonsult AB, Malmoe (Sweden)

    2000-06-01

    In this report a survey of the status with regard to the current understanding of what is causing superheater corrosion in biofueled CHP boilers is made together with an assessment of where knowledge and resources need to be strengthened. A division in three areas has been made: * Type of units/combustion, * Biofuels/combustion, and * Superheater materials. As yet, the knowledge and the results gained remain to be amalgamated in an effort to grasp the complex casual connections and course of events leading to corrosion. So far there are indications of important underlying factors and causes and it is also possible to make qualitative statements about possible mechanisms: * With high enough superheater surface temperatures (due to high steam temperatures) low-melting point alkali compounds caught in the deposit will start to melt. * Potassium chloride has a distinct and crucial roll with regard to the percentage of fluid in ash and deposits. This in turn is decisive for transport of corrosive elements, e.g. chlorine, between the deposit and the metal(oxide). * Poor combustion with e.g. plume formation and reducing atmosphere. Staged combustion for NO{sub x}-reduction, fine particle fractions giving rise to uncontrolled suspension combustion and short retention times are factors that contribute to the problem, not least by moving combustion up into the superheater area of the boiler. * The superheater position in the upper part of the furnace, where it is exposed to flame and particle radiation may increase the surface temperature of the deposit by several tens of degrees, which may be vital. A position in radiation protected areas indicates decreased corrosion(rates). * Conventional superheater materials made from (ferritic) low chromium steels originally designed for use in coal combustion are not adequate. Test results indicate that more highly alloyed (austenitic) materials that are used in waste-fired plants will be necessary. * Test results have revealed

  4. Nonlinear FOPDT Model Identification for the Superheat Dynamic in a Refrigeration System

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Sun, Zhen; Andersen, Casper

    2011-01-01

    the considered system is discretized, the nonlinear FOPDT identification problem is formulated as a Mixed Integer Non-Linear Programming problem, and then an identification algorithm is proposed by combining the Branch-and-Bound method and Least Square technique, in order to on-line identify these time......An on-line nonlinear FOPDT system identification method is proposed and applied to model the superheat dynamic in a supermarket refrigeration system. The considered nonlinear FOPDT model is an extension of the standard FOPDT model by means that its parameters are time dependent. After...

  5. Non-contact Measurement of Remaining Thickness of Corroding Superheater Tubes. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Borggreen, Kjeld; Storesund, Jan

    2006-10-15

    Corrosion of superheaters has become a severe problem in many biomass boilers and incineration plants. This new situation calls for frequent tube wall thickness testing of the superheaters during very short shut-downs. To meet this demand Electro Magnetic Acoustic Transducer (EMAT) candidates as substitute for conventional manually operated contact UT-transducers. The EMAT can contactlessly generate an ultrasonic wave in the interphase between the external oxide and the metal. This means that measurements can be undertaken much quicker and with a much higher coverage simultaneously, without preceding blast operations. It is the aim of the project to demonstrate the usefulness of two simple EMAT systems, Panametrics and Sonatest, for fast and reliable tube thickness inspections in difficult-to-access superheater sections. The present Phase 1 of the project involves testing of the performance of the two systems in laboratory with the following results: 1. Both instruments work well on plate, tube, and pipe samples assuming the presence of an external oxide layer formed at a temperature above approximately 400 deg C. 2. Both instruments work well on all types of ferritic and martensitic steels but not on austenitic steels. 3. Both instruments work well independent of the thickness of the active oxide layer. 4. Both instruments work well independent of tube diameter, wall thickness, and sample width. 5. Both instruments work well over a very large range of wall thicknesses. Minimum tube wall thickness is less than 1.8 mm. 6. The tolerable lift-off (free distance between transducer and tube surface) is 2.4 - 3.0 mm for Panametrics system and 3.6 - 4.8 mm for Sonatest's system. The tolerable lift-off is a measure of the thickness of ash deposits, which can be tolerated on the tube surface as well as the misplacement, which can be tolerated in case of remote tube testing. 7. The tolerable off-set between tube axis and probe axis is very large for both instruments (10

  6. Effect of melt superheat on microstructure of Al4Fe2Mn1.5 Monel alloy

    Institute of Scientific and Technical Information of China (English)

    WANG Fu; ZOU Jun-tao; WANG Xian-hui; FAN Zhi-kang

    2009-01-01

    The effect of melt superheat on microstructure of Al4Fe2Mn1.5 Monel alloy made by vacuum melting method was studied. The results show that the alloy consists of dendritic γ matrix and γ′ phase, wherein γ′ phase has two morphologies at different melt superheat. One is divorced eutectic γ′ which distributes in the interdendritic area, the other distributes dispersedly in single particle on the dendritic arm and exists in the petalform shape in the transition area between dendritic arm and interdendritic area. With the increase of superheat, the dendrite becomes finer, the primary dendritic arm is melted off and the secondary dendritic arm spacing decreases. The size of γ′ phase distributed on the dendritic arm becomes smaller and the divorced eutectic γ′ phase increases.

  7. Can the lifetime of the superheater tubes be predicted according to the fuel analyses? Assessment from field and laboratory data

    Energy Technology Data Exchange (ETDEWEB)

    Salmenoja, K. [Kvaerner Pulping Oy, Tampere (Finland)

    1998-12-31

    Lifetime of the superheaters in different power boilers is more or less still a mystery. This is especially true in firing biomass based fuels (biofuels), such as bark, forest residues, and straw. Due to the unhomogeneous nature of the biofuels, the lifetime of the superheaters may vary from case to case. Sometimes the lifetime is significantly shorter than originally expected, sometimes no corrosion even in the hottest tubes is observed. This is one of the main reasons why the boiler operators often demand for a better predictability on the corrosion resistance of the materials to avoid unscheduled shutdowns. (orig.) 9 refs.

  8. Probabilistic approach to determining the optimum replacement of a superheater stage in 680 MW coal-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Bos, Robert; Star, Ruud van der [Nuon Power Generation, Amsterdam (Netherlands)

    2009-07-01

    The boiler of the NUON power plant HW08 that went into operation in 1993 is designed as Benson boiler and mainly fired with hard coal. A creep-related tube failure occurred in the tertiary superheater that had been due to increased wall temperature caused by steam side formation of oxide layers. The theoretical lifetime of the components was calculated with the aid of the results of steam side oxide measurements and condition evaluation of the tertiary superheater with the aid of tube samples. The objective is to establish an operation and maintenance schedule for the desired operating lifetime of 300,000 hours. (orig.)

  9. Superheater corrosion in a boiler fired with refuse-derived fuel

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Stanko, G.J. [Foster Wheeler Development Corp., Livingston, NJ (United States); Bakker, W.T. [Electric Power Research Inst., Palo Alto, CA (United States); Steinbeck, T. [United Power Association, Elk River, MN (United States)

    1995-12-31

    The environment in the superheater of a boiler firing refuse-derived fuel (RDF) is very aggressive. The high wastage rate for the standard T-22 material necessitated a materials testing program. Simples of Types 304H, HR3C, T-22 chromized, 825 and 625 were assembled into tubular test sections and welded into the superheater tubing. After 1,180 hours the test sections were evaluated and the wastage rates calculated for each material. The chlorides contained in the RDF are believed to be the primary corrodent. The chlorine may be interacting with the metal samples as HCl, a low-melting-point eutectic or a combination of these. Of the six materials tested, Alloy 625 exhibited the best resistance--substantially better than the next-best Type 304. Alloy 825 and HR3C corroded approximately 1.5 times the rate of Type 304. The chromized layer on T-22 showed no resistance to the environment and was consumed in large areas.

  10. Superheater corrosion in biomass boiler - theories and tests in Vaestermalmsverket, Falun; Oeverhettarkorrosion i bioeldad panna - teorier och prov i Vaestermalmsverket, Falun

    Energy Technology Data Exchange (ETDEWEB)

    Roennquist, Eva-Marie

    2000-10-01

    It has lately been evident that a number of biomass-fired plants are experiencing major problems with corrosion of their superheaters. The major aim with this project is to contribute with increased knowledge in this area. The efforts to build up experience around different materials applicable for superheaters with high steam data is of great importance for future plants in Sweden. The main objective for 'Vaermeforsk' has been to transfer the experiences from this investigation to other boilers or plants with different types of fuel. This investigation has therefore been focused on the verification of SYCON's assumptions regarding the roles of chloride and alkali and the possibility of influencing/minimising superheater corrosion by optimisation of the fuel mix. Another important part was to verify that the boiler design, as such, does not create an unfavourable environment for the superheaters by producing reducing zones due to plume formation. Based on the above, the investigation has been divided into three loosely connected parts. (1) The role and reaction by chlorides in the deposits on a superheater, (2) Reducing environment - plume formation of non-combusted fuel, and (3) Choice of materials in the superheater. Serious corrosion has been detected in the superheater tubes of 'Vaestermalmsverket' in Falun. The material temperature was below 530 deg C. No serious inhomogeneous combustion problems or areas with reducing environments have been detected. The corrosion was therefore judged to be caused by alkali chlorides which condense on the superheater tubes. Tests with minor amounts of sulphur added to the biomass fuel have been shown to suppress the generation of alkali chlorides and their condensation on the superheater surfaces. A good correlation between calculated and measured values have been achieved. Very low corrosion rates have been measured on the test probes, constructed with different superheater material and placed in the

  11. The effects of tegaserod (HTF 919) on oesophageal acid exposure in gastro-oesophageal reflux disease.

    Science.gov (United States)

    Kahrilas, P J; Quigley, E M; Castell, D O; Spechler, S J

    2000-11-01

    Tegaserod (HTF 919), a 5-HT4 receptor partial agonist, has prokinetic effects that might be useful in decreasing acid reflux in gastro-oesophageal reflux disease (GERD). To investigate the potential clinical utility of tegaserod in GERD, a five-period crossover study (balanced Latin square) was designed to evaluate the efficacy of 4 b.d. doses of tegaserod vs. placebo. Four-hour manometry (1 h fasting and 3 h postprandial) with continuous recording of lower oesophageal sphincter pressure and distal oesophageal pH, was performed at the end of each 2-week treatment period in 19 patients with mild-to-moderate GERD. Recordings were scored for mean lower oesophageal sphincter pressure, number of transient lower oesophageal sphincter relaxations, and distal oesophageal acid exposure. Tegaserod (1 mg/day and 4 mg/day) caused a more than 50% decrease in acid exposure in the postprandial period in patients with abnormal acid exposure, although only the 1 mg/day tegaserod treatment elicited statistically significant decreasing (P < 0.05) for the entire treatment group (percentage time for which pH < 4: placebo=13%; 1 mg/day dose=5%; 4 mg/day dose=8%). A decreased number of reflux episodes was demonstrated with both the 1 mg/day and 4 mg/day tegaserod doses. There was no apparent effect on mean lower oesophageal sphincter pressure, whilst transient lower oesophageal sphincter relaxations frequency decreased in the 1-2.5 h post-dose. Tegaserod in a dose of 1 mg/day causes a significant decrease in postprandial oesophageal acid exposure. The reduction in oesophageal acid exposure with tegaserod treatment may result from enhanced oesophageal acid clearance, improved gastric emptying, and/or reduced transient lower oesophageal sphincter relaxations.

  12. Effect of meal timing not critical for the pharmacokinetics of tegaserod (HTF 919).

    Science.gov (United States)

    Zhou, H; Khalilieh, S; Lau, H; Guerret, M; Osborne, S; Alladina, L; Laurent, A L; McLeod, J F

    1999-09-01

    This study assessed the pharmacokinetic profiles of administering tegaserod (HTF 919) at different time intervals with respect to a meal. It was a randomized, open-label, two-phase, five-period crossover study. In the first phase, 18 healthy subjects received a single 12 mg oral dose of tegaserod administered either 30 or 15 minutes prior to the start of the 600-calorie, fat-rich breakfast. In the second phase, subjects received a single 12 mg oral dose of tegaserod 1 minute before, 2.5 hours after the start of meal, or with a continued 4-hour postdose fast. Safety assessment and plasma samples for the determination of drug concentration were obtained for 24 hours postdose. Noncompartmental analysis results indicated that the AUC of tegaserod was reduced by almost half under fed conditions compared to the fasted condition. Exploratory analyses were implemented to further investigate the absorption characteristics of tegaserod under different fed conditions. A numerical deconvolution approach was used to obtain the tegaserod oral absorption versus time profiles under both fasted and fed conditions. The tegaserod oral absorption versus time profiles were then fitted by NONMEM to a model containing two absorption phases. Based on the absorption analyses, we found that the reduction in the bioavailability of tegaserod under fed conditions was primarily due to a decrease in the extent of absorption and less so to a decrease in the absorption rate(s). Therefore, although the timing of administration of food does not appear to significantly alter the pharmacokinetics of tegaserod, the administration of food reduces the AUC by approximately 50%.

  13. Pre-oxidation and its effect on reducing high-temperature corrosion of superheater tubes during biomass firing

    DEFF Research Database (Denmark)

    Okoro, Sunday Chukwudi; Kvisgaard, M.; Montgomery, Melanie;

    2016-01-01

    Superheater tubes in biomass-fired power plants experience high corrosion rates due to condensation of corrosive alkali chloride-rich deposits. To explore the possibility of reducing the corrosion attack by the formation of an initial protective oxide layer, the corrosion resistance of pre-oxidis...

  14. 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)

  15. Numerical simulation of a thermal-bubble actuated diffuser-nozzle valveless pump

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A valveless micropump actuated by thermal bubbles which are generated by an electrode heater mounted with a pair of diffuser nozzles has been numerically studied by commercial CFD software FLUENT. The relationships between the net flow rate and the superheating and heat supplying frequency have been investigated. The depth of the diffuser-nozzle micropump is 200 μm, the diameter of the actuating chamber is 1 mm, and a pair of diffuser nozzles whose gap has been expanded from 30 μm to 274 μm with an open angle of 7° are connected to the actuating chamber. The working fluid is methanol. In the numerical simulation, the flow pattern is laminar. The results show that the pump has different optimal driving frequencies at different superheating. A cycle resulting from bubble growth and shrinking costs more time at higher superheating temperature; different superheating has different optimal driving frequency; when the superheating increases, the maximum volume flow rate and the maximum pump pressure will increase simultaneously, and the optimal driving frequency decreases as well, the maximum volume flow rate and pump pressure also have the same tendency; in the condition of uncontrolled condensing, the bubble shrinking process is longer than the growth process, thus it is the determining factor to affect the pump performance. The maximum volume flow rate is 9.02 μL/min at △T = 15℃, and the maximum pump pressure is 680 Pa. With the increase of wall superheat, cycle including the bubble growth and condensation will become longer, resulting in a significant impact on the pumping flow; different wall superheat has different optimized frequency, increasing superheat will bring increased pumping flow and pump pressure, the optimized driving frequency will be reduced; liquid supply phase is longer than pumping phase.

  16. In-Tank Precipitation Facility (ITP) and H-Tank Farm (HTF) geotechnical report, WSRC-TR-95-0057, Revision 0, Volume 4

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    A geotechnical study has been completed in H-Area for the In-Tank Precipitation Facility (ITP) and the balance of the H-Area Tank Farm (HTF) at the Savannah River Site (SRS) in South Carolina. The study consisted of subsurface field exploration, field and laboratory testing, and engineering analyses. The purpose of these investigations is to evaluate the overall stability of the H-Area tanks under static and dynamic conditions. The objectives of the study are to define the site-specific geological conditions at ITP and HTF, obtain engineering properties for the assessment of the stability of the native soils and embankment under static and dynamic loads (i.e., slope stability, liquefaction potential, and potential settlements), and derive properties for soil-structure interaction studies. This document (Volume 4) contains the laboratory test results for the In-Tank Precipitation Facility (ITP) and H-Tank Farm (HTF) Geotechnical Report.

  17. Premature failure of dissimilar metal weld joint at intermediate temperature superheater tube

    Directory of Open Access Journals (Sweden)

    Mohammed Al Hajri

    2015-04-01

    Full Text Available Dissimilar metal weld (DMW joint between alloyed steel (AS and stainless steel (SS failed at one of intermediate temperature superheater (ITSH tube in steam/power generation plant boiler. The premature failure was detected after a relatively short time of operation (8 years where the crack propagated circumferentially from AS side through the ITSH tube. Apart from physical examination, microstructural studies based on optical microscopy, SEM and EDX analysis were performed. The results of the investigation point out the limitation of Carbides precipitation at the alloyed steel/welding interface. This is synonym of creep stage I involvement in the failure of ITSH. Improper post-welding operation and bending moment are considered as root causes of the premature failure.

  18. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings - phase II

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Stanko, G.J. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1996-08-01

    In Phase I a variety of developmental and commercial tubing alloys and claddings were exposed to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. Phase II (in situ testing) has exposed samples of 347, RA-8511, HR3C, 253MA, Fe{sub 3}Al + 5Cr, 310 modified, 800HT, NF 709, 690 clad, and 671 clad for over 10,000 hours to the actual operating conditions of a 250-MW coal-fired boiler. The samples were installed on an air-cooled, retractable corrosion probe, installed in the reheater cavity, and controlled to the operating metal temperatures of an existing and advanced-cycle coal-fired boiler. Samples of each alloy will be exposed for 4000, 12,000, and 16,000 hours of operation. The results will be presented for the metallurgical examination of the corrosion probe samples after 4000 hours of exposure.

  19. Low Superheat Pouring with a Shear Field in Rheocasting of Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    GUO Hongmin; YANG Xiangjie; HU Bin

    2008-01-01

    A new rheocasting process,Low Superheat Pouring with a Shear Field(LSPSF),was developed to produce semi-solid slurry for the rheo-forming process.The LSPSF process is one of controlled nucleation and limited growth techniques in which effective nucleation rate is controlled by passive mixing and localized rapid cooling near the liquidus temperature;dendrite growth is limited by a much slower cooling process.The experimental results of rheocast Al-Cu alloy 201 and secondary diecasting alloy A380demonstrate that LSPSF process is capable of producing high-quality slurry in a matter of seconds.It is concluded that maximizing nucleation and nuclei survival directly lead to the grain refinement of the rheocasting microstructure,and high nuclei density combined with a slower cooling afterwards leads to a globular structure of primary phases.

  20. Correlation between molten vanadium salts and the structural degradation of HK-type steel superheater tubes

    Science.gov (United States)

    de Carvalho Nunes, Frederico; de Almeida, Luiz Henrique; Ribeiro, André Freitas

    2006-12-01

    HK steels are among the most used heat-resistant cast stainless steels, being corrosion-resistant and showing good mechanical properties at high service temperatures. These steels are widely used in reformer furnaces and as superheater tubes. During service, combustion gases leaving the burners come in contact with these tubes, resulting in corrosive attack and a large weight loss occurs due to the presence of vanadium, which forms low melting point salts, removing the protective oxide layer. In this work the external surface of a tube with dramatic wall thickness reduction was analyzed using light microscopy, scanning electron microscopy, and transmission electron microscopy. The identification of the phases was achieved by energy dispersive spectroscopy (EDS) analyses. The results showed oxides arising from the external surface. In this oxidized region vanadium compounds inside chromium carbide particles were also observed, due to inward vanadium diffusion during corrosion attack. A chemical reaction was proposed to explain the presence of vanadium in the metal microstructure.

  1. Effects of melatonin on in vitro development of mouse two-cell embryos cultured in HTF medium.

    Science.gov (United States)

    Tian, Xiu-Zhi; Wen, Qing; Shi, Jian-Min; Liang-Wang; Zeng, Shen-Ming; Tian, Jian-Hui; Zhou, Guang-Bin; Zhu, Shi-En; Liu, Guo-Shi

    2010-01-01

    Melatonin is capable of improving the developmental capacity of ovine, porcine and bovine embryos in vitro. However, whether melatonin possesses similar benefits to the in vitro mouse embryonic development has yet to be determined. In this study, we assessed the effects of various concentrations of melatonin (10-13 to 10-3 M) on the in-vitro development of mouse embryos cultured in HTF medium for 96 hr; embryos cultured without melatonin were used as control. The in vitro development of mouse two-cell embryos significantly benefited from treatment with melatonin in a concentration-dependent manner. The effects of melatonin on the rates of blastocyst formation, hatching/hatched blastocysts and cell number per blastocyst were bi-phasic; all significantly increased by melatonin at 10-13 to 10-5 M and decreased by melatonin at 10-3 M. Maximal benefit of melatonin on in vitro mouse 2-cell embryo development was achieved at a concentration of 10-9 M. In comparison to control, 10-9 M melatonin increased blastocyst formation rate from 48.08 +/- 5.25% to 82.08 +/- 2.34% (p HTF medium.

  2. The effects of tegaserod (HTF 919) on the pharmacokinetics and pharmacodynamics of digoxin in healthy subjects.

    Science.gov (United States)

    Zhou, H; Horowitz, A; Ledford, P C; Hubert, M; Appel-Dingemanse, S; Osborne, S; McLeod, J F

    2001-10-01

    Tegaserod (HTF 919) is a highly specific 5-HT4 receptor partial agonist that exhibits promotile activity throughout the gastrointestinal tract and is under development for the treatment of functional gastrointestinal motility disorders. The present study was designed to assess the effect of multiple doses of tegaserod on the single-dose pharmacokinetics and pharmacodynamics of digoxin, a commonly prescribed agent for congestive heart failure. The study was an open-label, randomized, two-period crossover design of 12 healthy subjects. One treatment included digoxin treatment alone; the other treatment included a combined digoxin and tegaserod treatment. On day 1 of the digoxin treatment period, subjects received a single 1 mg oral dose of digoxin. In the combined tegaserod/digoxin treatment period, subjects received a single oral dose of 1 mg digoxin after 3 days of tegaserod (6 mg bid). After coadministration of tegaserod, systemic exposure to digoxin was decreased; mean AUC decreased by 11.9% (p < 0.05) relative to digoxin alone. Cmax was decreased by about 15% (p < 0.05). The 0.5-hour difference in the median tmax between the two treatments was not statistically significant. Because the steady-state trough concentration of digoxin (C(SS,min)) correlates with pharmacological effects, C(SS,min) for digoxin alone and in combination with tegaserod was simulated based on both parametric compartmental modeling and nonparametric superpositioning approaches. The predicted arithmetic mean C(SS,min) for combination therapy is 86% to 89% of that following digoxin alone. Likewise, the predicted arithmetic mean steady-state peak concentration (C(SS,min)) and AUC at steady state during a dosing interval (AUC(SS,tau)) have a similar decrease. This extent of decrease in systemic exposure of digoxin at steady state is unlikely to be clinically relevant. Administration of tegaserod (6 mg bid) was well tolerated, both alone and in combination with a single dose of digoxin. There

  3. Superheater corrosion improved utilization of gained experience; Oeverhettarkorrosion - baettre utnyttjande av projektresultat

    Energy Technology Data Exchange (ETDEWEB)

    Nystroem, Olle; Ehrstedt, Thomas [Carl Bro Energikonsult AB, Stockholm (Sweden); Kjoerk, Anders [S.E.P. Scandinavian Energy Projects AB (Sweden)

    2004-01-01

    Superheater corrosion has been a problem in many biofuelled district heating and cogeneration plants. Even if this 'disease' easily can be diagnosed and the immediate mechanisms about how and why it develops are relatively well known, the underlying causes, which the individual plant owner has to live with, represent a diversity of complex causes and effects. The conditions may vary from plant to plant, a fact, which would normally represent a difficulty with regard to a full-fledged analysis, but often some common elements can be identified for a prefatory analysis. Analysis would be facilitated with access to a tool enabling a systematic gathering of plant operation data. Vaermeforsk (Thermal Engineering Research Institute) and its Chemical and Material Technology group have discussed the need of a database, which combines the requirements among plant owners/operators on one side and researchers/developers on the other. In this report a database meeting these requirements is presented. The database is based on Access 2000 and made available at the Vaermeforsk homepage (www.varmeforsk.se). It is a database where any piece of information is found in one specific site or memory within it. These sites/memories taking the form of tables are linked to each other. To be able to characterise a specific plant/boiler and specify the conditions of interest, detailed information is required. The database input is based on information that seems relevant with regard to output and which also can be quantified with reasonable effort. Data have been structured in five areas/domains covering: the plant, the superheater, the case(report), the material and the fuel. A case description/form, which constitutes the core of the database, is presented in the table 'Fall' (Case), where information/data related to steam data, standard fuel mix, deposit and flue gas analysis etc. plus information about corrosion for a certain superheater in a specific plant are

  4. HTF: A b-ZIP transcription factor that is closely related to the human XBP/TREB5 and is activated by hepatocellular carcinoma in rats.

    Science.gov (United States)

    Kishimoto, T; Kokura, K; Kumagai, Y; Wakamatsu, T; Makino, Y; Tamura, T

    1996-06-25

    We screened for rat hepatocellular carcinoma (HCC)-related genes by a novel cDNA subtraction method and obtained one gene. This gene was transcribed as 2.0- and 2.5-kb mRNAs, and its transcription was specifically enhanced in HCC. These cDNAs had the same open reading frame, but the 2.5 kb transcript had an extra 495 bases of 5'-UTR at the 5'-terminus. The deduced aa sequence revealed a basic-leucine zipper (b-ZIP) and proline/glutamine-rich structures, both of which are characteristic motifs for transcription factors. We designated the translation product of this gene HTF (Hepatocarcinogenesis-related Transcription Factor). Electrophoretic mobility shift assay demonstrated the DNA-binding ability of the recombinant HTF. It is most interesting that HTF had a considerable homology with human XBP/TREB5, which has been reported to be a binding factor for the X-box of the MHC class II gene and for the 21-bp enhancer of the HTLV-1 LTR. Genomic Southern analysis suggested that the 2.0- and 2.5-kb mRNAs are transcribed by a dual promoter of a single gene. Our results may suggest that HTF is a b-ZIP-type transcription factor involved in rat hepatocellular carcinoma.

  5. Experimental research on heat transfer to liquid sodium and its incipient boiling wall superheat in an annulus

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Liquid sodium is mainly used as a cooling fluid in the liquid metal fast breeder reactor (LMFBR), whose heat transfer, whether convective heat transfer or boiling heat transfer, is different from that of water. So it is important for both normal and accidental operations of LMFBR to perform experimental research on heat transfer to liquid sodium and its boiling heat transfer. This study deals with heat transfer with high temperature (300-700℃) and low Pe number (20~70) and heat transfer with low temperature (250~270℃) and high Pe number (125~860), and its incipient boiling wall superheat in an annulus. Research on heat transfer involves theoretical research and experiments on heat transfer to liquid sodium. It also focuses on the theoretical analysis and experimental research on its incipient boiling wall superheat at positive pressure in an annulus. Semiempirical correlations were obtained and they were well coincident with the experimental data.

  6. Research on semi-solid slurry of a hypoeutectic Al-Si alloy prepared by low superheat pouring and weak electromagnetic stirring

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The semi-solid slurry of a hypoeutectic Al-Si alloy was manufactured by low superheat pouring and weak electromagnetic stirring. The effects of pouring temperature and stirring power on the semi-solid slurry were investigated. The results indicated that the semi-solid slurry to satisfy rheocasting can be manufactured by low superheat pouring and weak electromagnetic stirring. The pouring temperature (or superheat) and the stirring power remarkably affected the morphology of primary α-Al and the size of primary α-Al, and there is no obvious effect of stirring time on primary α-Al. Compared with the samples made by low superheat pouring with no stirring, the nucleation rate, particle morphology and grain size of primary α-Al in A356 were markedly improved by low superheat pouring and weak electromagnetic stirring. On the condition of weak electromagnetic stirring, the pouting temperature with low superheat can be suitably raised to reach the effectiveness obtained from the lower pouring temperature without stirring.

  7. Manufacture technique of semi-solid slurry of hypoeutectic Al-Si alloy by low superheat pouring and weak electromagnetic stirring

    Institute of Scientific and Technical Information of China (English)

    LIU Zheng; MAO Wei-ming; ZHAO Zheng-duo

    2006-01-01

    The semi-solid slurry of hypoeutectic Al-Si alloy was manufactured by low superheat pouring and weak electromagnetic stirring. The effects of pouring temperature and stirring power on the semi-solid slurry making process were investigated. The results indicate that the semi-solid slurry to satisfy rheocasting requirement can be made by a combination of low superheat pouring and weak electromagnetic stirring. The pouring temperature (or superheat) and the stirring power significantly affect the morphology and the size of primary α-Al, while there is no obvious effect of the stirring time on primary α-Al. Compared with the samples made by low superheat pouring without stirring, the nucleation rate,particle morphology and grain size of primary α-Al in A356 Al alloy are markedly improved by a process of applying both low superheat pouring and weak electromagnetic stirring. Under the condition of weak electromagnetic stirring applied, the pouring temperature with low superheat can be equivalerttly to reach the effectiveness obtained from the even lower pouring temperature without stirring.

  8. Manufacture technique of semi-solid slurry of hypoeutectic Al-Si alloy by low superheat pouring and weak electromagnetic stirring

    Directory of Open Access Journals (Sweden)

    LIU Zheng

    2006-05-01

    Full Text Available The semi-solid slurry of hypoeutectic Al-Si alloy was manufactured by low superheat pouring and weak electromagnetic stirring. The effects of pouring temperature and stirring power on the semi-solid slurry making process were investigated. The results indicate that the semi-solid slurry to satisfy rheocasting requirement can be made by a combination of low superheat pouring and weak electromagnetic stirring. The pouring temperature (or superheat and the stirring power significantly affect the morphology and the size of primary α-Al, while there is no obvious effect of the stirring time on primary α-Al. Compared with the samples made by low superheat pouring without stirring, the nucleation rate, particle morphology and grain size of primary α-Al in A356 Al alloy are markedly improved by a process of applying both low superheat pouring and weak electromagnetic stirring. Under the condition of weak electromagnetic stirring applied, the pouring temperature with low superheat can be equivalently to reach the effectiveness obtained from the even lower pouring temperature without stirring.

  9. A computational approach for thermomechanical fatigue life prediction of dissimilarly welded superheater tubes

    Energy Technology Data Exchange (ETDEWEB)

    Krishnasamy, Ram-Kumar; Seifert, Thomas; Siegele, Dieter [Fraunhofer-Institut fuer Werkstoffmechanik (IWM), Freiburg im Breisgau (Germany)

    2010-07-01

    In this paper a computational approach for fatigue life prediction of dissimilarly welded superheater tubes is presented and applied to a dissimilar weld between tubes made of the nickel base alloy Alloy617 tube and the 12% chromium steel VM12. The approach comprises the calculation of the residual stresses in the welded tubes with a multi-pass dissimilar welding simulation, the relaxation of the residual stresses in a post weld heat treatment (PWHT) simulation and the fatigue life prediction using the remaining residual stresses as initial condition. A cyclic fiscoplasticity model is used to calculate the transient stresses and strains under thermocyclic service loadings. The fatigue life is predicted with a damage parameter which is based on fracture mechanics. The adjustable parameters of the model are determined based on LCF and TMF experiments. The simulations show, that the residual stresses that remain after PWHT further relax in the first loading cycles. The predicted fatigue lives depend on the residual stresses and, thus, on the choice of the loading cycle in which the damage parameter is evaluated. It the first loading cycle, where residual stresses are still present, is considered, lower fatigue lives are predicted compared to predictions considering loading cycles with relaxed residual stresses. (orig.)

  10. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings -- Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Seitz, W.W. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1997-12-01

    In Phase 1 a variety of developmental and commercial tubing alloys and claddings were exposed to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. Phase 2 (in situ testing) has exposed samples of 347 RA-85H, HR3C, 253MA, Fe{sub 3}Al + 5Cr, 310 Ta modified, NF 709, 690 clad, and 671 clad for approximately 4,000, 12,000, and 16,000 hours to the actual operating conditions of a 250-MW coal-fired boiler. The samples were assembled on an air-cooled, retractable corrosion probe, the probe was installed in the reheater activity of the boiler and controlled to the operating metal temperatures of an existing and advanced-cycle coal-fired boiler. The results will be presented for the preliminary metallurgical examination of the corrosion probe samples after 16,000 hours of exposure. Continued metallurgical and interpretive analysis is still on going.

  11. Comparison between two rheocasting processes of damper cooling tube method and low superheat casting

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoli; Ling Xiangjun; Wang Tongmin; Li Tingju

    2014-01-01

    To produce a high quality semisolid slurry that consists of fine primary particles uniformly suspended in the liquid matrix for rheoforming, chemical refining and electromagnetic or mechanical stirring are the two methods commonly used. But these two methods either contaminate the melt or incur high cost. In this study, the damper cooling tube (DCT) method was designed to prepare semisolid slurry of A356 aluminum alloy, and was compared with the low superheat casting (LSC) method - a conventional process used to produce casting slab with equiaxed dendrite microstructure for thixoforming route. A series of comparative experiments were performed at the pouring temperatures of 650 °C, 638 °C and 622 °C. Metal ographic observations of the casting samples were carried out using an optical electron microscope with image analysis software. Results show that the microstructure of semisolid slurry produced by the DCT process consists of spherical primary α-Al grains, while equiaxed grains microstructure is found in the LSC process. The lower the pouring temperature, the smal er the grain size and the rounder the grain morphology in both methods. The copious nucleation, which could be generated in the DCT, owing to the cooling and stirring effect, is the key to producing high quality semisolid slurry. DCT method could produce rounder and smal er α-Al grains, which are suitable for semisolid processing; and the equivalent grain size is no more than 60 µm when the pouring temperature is 622 °C.

  12. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings -- Phase 2 field testing

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Seitz, W.W.; Girshik, A. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1998-06-01

    In Phase 1 of this project, laboratory experiments were performed on a variety of developmental and commercial tubing alloys and claddings by exposing them to fireside corrosion tests which simulated a superheater or reheater in a coal-fired boiler. Phase 2 (in situ testing) has exposed samples of 347, RA85H, HR3C, RA253MA, Fe{sub 3}Al + 5Cr, Ta-modified 310, NF 709, 690 clad, 671 clad, and 800HT for up to approximately 16,000 hours to the actual operating conditions of a 250-MW, coal-fired boiler. The samples were installed on air-cooled, retractable corrosion probes, installed in the reheater cavity, and controlled to the operating metal temperatures of an existing and advanced-cycle, coal-fired boiler. Samples of each alloy were exposed for 4,483, 11,348, and 15,883 hours of operation. The present results are for the metallurgical examination of the corrosion probe samples after the full 15,883 hours of exposure. A previous topical report has been issued for the 4,483 hours of exposure.

  13. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings - Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Krawchuk, M.T.; Van Weele, S.F. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1995-08-01

    A number of developmental and commercial tubing alloys and claddings have previously been exposed in Phase I to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. This program is exposing samples of TP 347, RA-85H, HR-3C, 253MA, Fe{sub 3}Al + 5Cr, 310 modified, NF-709, 690 clad, and 671 clad, which showed good corrosion resistance from Phase 1, to the actual operating conditions of a 250-MW, coal-fired boiler. The samples were installed on air-cooled, retractable corrosion probes, installed in the reheater cavity, and are being controlled to the operating metal temperatures of an existing and advanced-cycle coal-fired boiler. The exposure will continue for 4000, 12,000, and 16,000 hours of operation. After the three exposure times, the samples will be metallurgically examined to determine the wastage rates and mode of attack. The probes were commissioned November 16, 1994. The temperatures are being recorded every 15 minutes, and the weighted average temperature calculated for each sample. Each of the alloys is being exposed to a temperature in each of two temperature bands-1150 to 1260{degrees}F and 1260 to 1325{degrees}F. After 2000 hours of exposure, one of the corrosion probes was cleaned and the wall thicknesses were ultrasonically measured. The alloy performance from the field probes will be discussed.

  14. Comparison between two rheocasting processes of damper cooling tube method and low superheat casting

    Directory of Open Access Journals (Sweden)

    Zhang Xiaoli

    2014-09-01

    Full Text Available To produce a high quality semisolid slurry that consists of fine primary particles uniformly suspended in the liquid matrix for rheoforming, chemical refining and electromagnetic or mechanical stirring are the two methods commonly used. But these two methods either contaminate the melt or incur high cost. In this study, the damper cooling tube (DCT method was designed to prepare semisolid slurry of A356 aluminum alloy, and was compared with the low superheat casting (LSC method - a conventional process used to produce casting slab with equiaxed dendrite microstructure for thixoforming route. A series of comparative experiments were performed at the pouring temperatures of 650 °C, 638 °C and 622 °C. Metallographic observations of the casting samples were carried out using an optical electron microscope with image analysis software. Results show that the microstructure of semisolid slurry produced by the DCT process consists of spherical primary α-Al grains, while equiaxed grains microstructure is found in the LSC process. The lower the pouring temperature, the smaller the grain size and the rounder the grain morphology in both methods. The copious nucleation, which could be generated in the DCT, owing to the cooling and stirring effect, is the key to producing high quality semisolid slurry. DCT method could produce rounder and smaller α-Al grains, which are suitable for semisolid processing; and the equivalent grain size is no more than 60 μm when the pouring temperature is 622 °C.

  15. 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

  16. 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....

  17. Results of examination of the TGMP-314 boiler superheaters of the power-generating units at Kashira state district power plant using a magnetic ferrite meter

    Science.gov (United States)

    Bogachev, V. A.; Pshechenkova, T. P.; Shumovskaya, M. A.

    2016-07-01

    The results of investigating the elemental composition of the scale and the metal of a tube circuit from the austenitic steel grade 12Cr18Ni12Ti are presented. The superheater is part of the high-pressure convection steam superheater of a TGMP-314 supercritical-pressure gas-and-oil-fired once-through boiler that had been operated for a long period of time. A structurally transformed layer, poor in iron, manganese, and chromium and rich in nickel was detected on the outer surface. The layer consisted predominantly of the FeNi3 phase with ferromagnetic properties. The heat-resistance test of the steel in contact with ash that simulated the combustion products of fuel oil showed that the higher the temperature and the longer the test time, the higher the content of the ferritic phase in the layer was. The established pattern of the structural transformations underlies a method for nondestructive control of the thermal nonuniformity and detection of "worst" tube circuits of superheaters from austenitic steel. The magnetic ferritometry complements the conventional selective thickness gauging that does not characterize the condition of the heating surfaces of hightemperature steel grades to the full extend. Data on damageability of high-pressure convection superheaters and low-pressure second-stage convection superheaters with rarefied tube banks of TGMP-314 boilers are presented. The damage is caused by overheating resulting from the nonuniform temperature field at the inlet and by the nonuniform flue gas velocity field in rarefied superheater banks. Sections of the tube circuits from the steel grade 12Cr18Ni12Ti, outlet superheater stages of the TGMP-314 boiler of the power-generating units at Kashira SDPP were examined using an MF-51NTs AKASKAN magnetic ferrite meter. Thermal nonuniformity was established and the "worst" superheater tube circuits were detected. It was shown that the zones with the "worst" and damaged tube circuits coincide. The results of examining

  18. Effect of electrolysis superheat degree on anticorrosion performance of 5Cu/(10NiO-NiFe2O4) cermet inert anode

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    5Cu/(10NiO-NiFe2O4) cermet inert anodes were prepared by cold-pressing and sintering process, and the effect of superheat degree of melting K3AIF6-Na3AlF6-AlF3 on their anticorrosion performance was studied under electrolysis conditions. The results show that, the fluctuation of cell becomes small with increasing of superheat degree, which is helpful to inhibit the formation of cathodic encrustation; the concentration of impurities from inert anode in bath goes up to certain degree, but it is far smaller than those in traditional high-temperature bath. Increasing the superheat degree of melting K3AlF6-Na3AlF6-AlF3 has unconspicuous effect on the contents of impurities in cathodic aluminum. The total mass fractions of Fe, Ni and Cu in aluminum are 15.38% and15.09% respectively under superheat degree of 95 and 195 ℃C. From micro-topography of anode used view, increasing the superheat degree can aggravate corrosion of metal Cu in inert anode, and has negative influence on electrical conductivity of electrode to some extent.

  19. In-tank Precipitation Facility (ITP) and H-Tank Farm (HTF) geotechnical report, WSRC-TR-95-0057, Revision 0, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    A geotechnical study has been completed in H-Area for the In-Tank Precipitation Facility (ITP) and the balance of the H-Area Tank Farm (HTF) at the Savannah River Site (SRS) in South Carolina. The study consisted of subsurface field exploration, field and laboratory testing, and engineering analyses. The purpose of these investigations is to evaluate the overall stability of the H-Area tanks under static and dynamic conditions. The objectives of the study are to define the site-specific geological conditions at ITP and HTF, obtain engineering properties for the assessment of the stability of the native soils and embankment under static and dynamic loads (i.e., slope stability, liquefaction potential, and potential settlements), and derive properties for soil-structure interaction studies.

  20. On-line Auto-Tuning of PI Control of the Superheat for a Supermarket Refrigeration System

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Andersen, Casper; Izadi-Zamanabadi, Roozbeh

    2011-01-01

    An online PI auto-tuning method is proposed for superheat control for a type of supermarket refrigeration systems. The proposed procedure consists of three serial steps: Step-One uses one of the two proposed empirical methods, namely multi-step method and relay method, for modeling initialization...... controller is auto-tuned based on the obtained FOPDT model and the SIMC method in Step-Three. The proposed method is implemented on a real-sized physical system and the experimental results showed a promising potential to apply the proposed method into commercial development....

  1. Damage distribution and remnant life assessment of a super-heater outlet header used for long time

    Energy Technology Data Exchange (ETDEWEB)

    Hiroyuki, Okamura [Science Univ. of Tokyo (Japan); Ryuichi, Ohotani [Kyoto Univ. (Japan); Kazuya, Fujii [Japan Power Engineering and Inspection Corp., Tokyo (Japan); Masashi, Nakashiro; Fumio, Takemasa; Hideo, Umaki; Tomiyasu, Masumura [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)

    1998-11-01

    This paper presents the results of investigation on evaluating damage distribution to base metals and welded joints in the thickness direction and evaluate damage on ligaments. Thick wall tested sample was the superheater outlet header component long term serviced in high pressure and temperature condition in thermal power plant. The simulate unused steel of component material was made from sample by suitable heat treatment, and the extent of damage was assessed based on a comparison of nondestructive and destructive test results between simulate unused and aged samples. Damage evaluation was also made by FEM structural stress analysis. (orig./MM)

  2. On-line Auto-Tuning of PI Control of the Superheat for a Supermarket Refrigeration System

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Andersen, Casper; Izadi-Zamanabadi, Roozbeh

    2011-01-01

    An online PI auto-tuning method is proposed for superheat control for a type of supermarket refrigeration systems. The proposed procedure consists of three serial steps: Step-One uses one of the two proposed empirical methods, namely multi-step method and relay method, for modeling initialization...... controller is auto-tuned based on the obtained FOPDT model and the SIMC method in Step-Three. The proposed method is implemented on a real-sized physical system and the experimental results showed a promising potential to apply the proposed method into commercial development....

  3. Integrated modelling of the clinical pharmacokinetics of SDZ HTF 919, a novel selective 5-HT4 receptor agonist, following oral and intravenous administration.

    Science.gov (United States)

    Appel-Dingemanse, S; Lemarechal, M O; Kumle, A; Hubert, M; Legangneux, E

    1999-05-01

    The purpose of the present study was to assess the pharmacokinetics of the novel selective 5-HT4 receptor agonist SDZ HTF 919 (HTF) including food effect, absolute bioavailability, interoccasion and intersubject variabilities. In the randomized, open-label, three treatment, four period crossover study, HTF was administered to 12 young healthy male subjects as a 12 mg tablet (twice under fasted and once under fed conditions) and a 3 mg intravenous (i.v.) infusion over 40 min (fasted). Pharmacokinetic parameters were obtained by noncompartmental methods. A more comprehensive pharmacokinetic characterization was achieved by integrated modelling of oral (p.o.) and i.v. data. To describe the absorption phase a Weibull function and a classical first order input function were compared. Noncompartmental pharmacokinetic analysis revealed a rapid absorption (tmax 1.3 h, fasted), an absolute bioavailability of 11+/-3%, a biphasic disposition phase with a terminal half-life of 11+/-5 h, a clearance of 77+/-15 l h-1, and a volume of distribution at steady state of 368+/-223 l. The coefficients of interoccasion and interindividual variability in Cmax and AUC ranged between 17 and 28%. Food intake caused a delay (tmax 2.0 h) and decrease in absorption with consequently lower systemic exposure ( approximately 5% absolute bioavailability). Integrated p.o./i.v. pharmacokinetic modelling with a Weibull input function allowed accurate description of individual profiles. Modelling of the data from the p.o. dosing improved the description of the terminal phase by inclusion of the i. v. data and additionally provided quantitative characterization of the absorption phase. The pharmacokinetics of HTF could be well described by an integrated modelling approach for both p.o. and i.v. data. The derived model will provide guidance in the design of future studies.

  4. 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.

  5. Multi-Temperature Heat Pump with Cascade Compressor Connection

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2017-08-01

    Full Text Available The object of the study is a multifunctional heat pump with several evaporators and condensers designed for simultaneous provision of technological processes with heat and cold. The aim of the work is the development and study of the scheme for this type of heat pumps, which ensures minimum irreversibility in the "compressor-gas coolers" chain, without the use of adjustable ejectors installed after evaporators and used as flow mixers. The obtained technical solution ensures the stabilization of the heat pump coefficient of performance (COP and prescribed thermal regimes of heat exchangers at a variable flow rate of the refrigerant. The novelty of the elaboration is inclusion a compressor of the first stage with a serially connected intermediate heat exchanger and a control valve that are located before the compressor inlet of the second stage of the heat pump, which allows to establish a rational pressure after the first stage of the compressors. A scheme is proposed for regulating the temperature at the inlet of the first stage compressors by regulating the flow through the primary circuits of the recuperative heat exchangers. The first stage compressor control system allows providing the required modes of operation of the heat pump. It is established, because of the exergetic analysis of the sections of the hydraulic circuit of heat pump located between the evaporators and gas coolers that the reduction of irreversible losses in the heat pump is ensured due to the optimal choice of the superheat value of the gas after the evaporators.

  6. 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.

  7. Effect of superheat, mold, and casting materials on the metal/mold interfacial heat transfer during solidification in graphite-lined permanent molds

    Science.gov (United States)

    Prabhu, K. Narayan; Suresha, K. M.

    2004-10-01

    Heat transfer during the solidification of an Al-Cu-Si alloy (LM4) and commercial pure tin in single steel, graphite, and graphite-lined metallic (composite) molds was investigated. Experiments were carried out at three different superheats. In the case of composite molds, the effect of the thickness of the graphite lining and the outer wall on heat transfer was studied. Temperatures at known locations inside the mold and casting were used to solve the Fourier heat conduction equation inversely to yield the casting/mold interfacial heat flux transients. Increased melt superheats and higher thermal conductivity of the mold material led to an increase in the peak heat flux at the metal/mold interface. Factorial experiments indicated that the mold material had a significant effect on the peak heat flux at the 5% level of significance. The ratio of graphite lining to outer steel wall and superheat had a significant effect on the peak heat flux in significance range varying between 5 and 25%. A heat flux model was proposed to estimate the maximum heat flux transients at different superheat levels of 25 to 75 °C for any metal/mold combinations having a thermal diffusivity ratio (α R) varying between 0.25 and 6.96. The heat flow models could be used to estimate interfacial heat flux transients from the thermophysical properties of the mold and cast materials and the melt superheat. Metallographic analysis indicated finer microstructures for castings poured at increased melt superheats and cast in high-thermal diffusivity molds.

  8. Superheater failures in ultra supercritical boilers - cases from Fynsvaerket, Vestkraft, and Skaerbaekvaerket power plants; Ueberhitzerschaeden in Kesseln mit fortschrittlichen Dampfparametern - Fallbeispiele aus den Kraftwerken Fynsvaerket, Vestkraft und Skaerbaekvaerket

    Energy Technology Data Exchange (ETDEWEB)

    Blum, R.; Larsen, O.H.; Henriksen, N.

    1999-12-01

    Superheater and reheater failures are well known problems in existing power boilers and a potential problem of great importance in new ultra supercritical (USC) plants. Unexpected shut downs caused by leaking superheater and reheater tubes affect the availability of the plant and thereby the overall plant economics. Overheating due to an incorrect balance of the actual temperature level, heat flux and cooling causes most of the superheater and reheater failures. Elsam has been dealing with these problems for many years, and based on experience gained from in service plants and from different in-plant test facilities a powerful simulation calculation programme has been set up. Using this programme it has been possible to explain the failures, assess the remaining lifetime of superheater or reheater sections and make correct simulations and assessments of superheater and reheater design in new boilers with advanced steam parameters. A detailed description of this calculation programme has been given in former papers. In this paper, examples of such evaluations will be given describing three cases where severe superheater failures were experienced in supercritical once through boilers. (orig.) [German] Ueberhitzer- und Zwischenueberhitzerschaeden sind in bestehenden Kraftwerkskesseln bekannt und stellen ein potentielles Problem groesster Wichtigkeit in neuen Anlagen mit fortgeschrittenen Dampfparametern dar. Unerwartete Betriebsunterbrechungen durch Leckagen von Ueberhitzer- und Zwischenueberhitzerrohren beeintraechtigen die Kraftwerksverfuegbarkeit und dadurch die Wirtschaftlichkeit. Ueberhitzung als Folge von Temperaturschieflagen, von inkorrekten Waermestromdichten und Kuehlung verursacht die meisten Ueberhitzer- und Zwischenueberhitzerschaeden. ELSAM befasst sich seit vielen Jahren mit diesem Problem. Anhand der Erfahrungen aus den Anlagen in Betrieb und Ergebnissen von verschiedenen Teststaenden in Kraftwerken wurde ein leistungsfaehiges Computerprogramm

  9. 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

  10. Production of A356 aluminum alloy wheels by thixo-forging combined with a low superheat casting process

    Directory of Open Access Journals (Sweden)

    Wang Shuncheng

    2013-09-01

    Full Text Available The A356 aluminum alloy wheels were produced by thixo-forging combined with a low superheat casting process. The as-cast microstructure, microstructure evolution during reheating and the mechanical properties of thixo-forged wheels made from the A356 aluminum alloy were studied. The results show that the A356 aluminum alloy round billet with fine, uniform and non-dendritic grains can be obtained when the melt is cast at 635 篊. When the round billet is reheated at 600 篊 for 60 min, the non-dendritic grains are changed into spherical ones and the round billet can be easily thixo-forged into wheels. The tensile strength, yield strength and elongation of the thixo-forged wheels with T6 heat treatment are 327.6 MPa, 228.3 MPa and 7.8%, respectively, which are higher than those of a cast wheel. It is suggested that the thixo-forging combined with the low superheat casting process is an effective technique to produce aluminum alloy wheels with high mechanical properties.

  11. Multiple-dose pharmacokinetics confirm no accumulation and dose proportionality of the novel promotile drug tegaserod (HTF 919).

    Science.gov (United States)

    Appel-Dingemanse, S; Hirschberg, Y; Osborne, S; Pommier, F; McLeod, J

    2001-03-01

    To evaluate the steady-state pharmacokinetics (PK) and dose proportionality of the selective 5-HT4 receptor partial agonist tegaserod (HTF 919) in healthy subjects. Eighteen subjects were given 2, 6, or 12-mg doses of tegaserod twice daily (b.i.d.) for 5 days, with PK and safety assessments made during the 12 h or 24 h following first administration, and 12 h after the final dose. Tegaserod was rapidly absorbed [time to reach measured maximum plasma concentration after multiple administrations (tmax,ss) 1 h]. Steady-state PK were consistent with single-dose PK characteristics supporting that there was no accumulation of tegaserod in plasma based on systemic exposure. Mean measured maximum plasma concentration after multiple administrations (Cmax,ss) and area under the plasma concentration-time curve over one dosing interval (tau, 0-12 h after drug administration, AUC tau) were between 0.7 +/- 0.3 ng/ml and 5.6 +/- 2.9 ng/ml and 2.4 +/- 1.3 h.ng/ml and 20.4 +/- 14.0 h.ng/ml, respectively, indicating dose-proportional PK of tegaserod in the range 2-12 mg b.i.d. Tegaserod was safe and well tolerated. No serious adverse events were reported. Tegaserod exhibits no accumulation and dose-proportional PK after multiple doses.

  12. 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...

  13. On the influence of chlorides and sulphureous compounds on the corrosion of superheater tubes in boilers with special consideration on kraft recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Fredrik [AaF-IPK AB, Stockholm (Sweden)

    1999-03-01

    This report reviews the thermochemistry of the most relevant corrosion reactions and mechanisms with chloride especially considering the kraft pulp mill recovery boiler. The flue gas side corrosion of superheater tubes is governed by the fuel constituents, and by the carryover particles and the gaseous impurities accompanying the flue gases and the local chemical conditions they cause on the superheater tube surface. A study made on coal-fired boilers in Germany has been interpreted so that the protective ability of the oxide layer on the tube surface of a superheater tube is limited, which causes a close to linear time dependence of the material loss due to corrosion. The thermochemistry of the reactions of the protective oxide layer itself with the components of the deposited carryover and the flue gas sulphur components seems thus to govern the mechanism of the corrosion. The corrosion in the recovery boiler is concluded to be more dependant on this combined action of carry-over and sulphureous oxides, so the presence of chlorides in the flue gases only influences the melting range properties of the sulphate deposits, but seems to exert less influence on the chemical reactions which attack the oxides of the passive layer. The thermochemistry also explains the formation of a sulphide layer often found between the deposits and the surface of the tube metal on superheater tubes as a result of reaction with sulpureous oxides from the flue gas and carbon in the carryover. The factors which in practice limit the superheater corrosion in the recovery boiler are interpreted as both material and process dependent. The main limiting factor for the steam temperature is still the melting range of the sulphate deposit. There seems thus to be little hope for the aim to raise the steam temperature of the kraft recovery boiler above the range which is already achievable with the presently available composite tubes 22 refs, 10 figs

  14. Evaluation of the behavior of shrouded plasma spray coatings in the platen superheater of coal-fired boilers

    Science.gov (United States)

    Sidhu, Buta Singh; Prakash, S.

    2006-06-01

    Nickel- and cobalt-based coatings were formulated by a shrouded plasma spray process on boiler tube steels, namely, ASTM-SA210-grade A1 (GrA1), ASTM-SA213-T-11 (T11), and ASTM-SA213-T-22 (T22). The Ni-22Cr-10Al-1Y alloy powder was sprayed as a bond in each case before the final coating. The degradation behavior of the bared and coated steels was studied in the platen superheater of the coal-fired boiler. The samples were inserted through the soot blower dummy points with the help of stainless steel wires. The coatings were found to be effective in increasing resistance to degradation in the given boiler environment. The maximum protection was observed in the case of Stellite-6 (St-6) coating.

  15. Evaluation of the behavior of shrouded plasma spray coatings in the platen superheater of coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, B.S.; Prakash, S. [GZS College of Engineering & Technology, Bathinda (India). Dept. of Mechanical Engineering

    2006-06-15

    Nickel- and cobalt-based coatings were formulated by a shrouded plasma spray process on boiler tube steels, namely, ASTM-SA210-grade A1 (GrA1), ASTM-SA213-T-11 (T11), and ASTM-SA213-T-22 (T22). The Ni-22Cr-10A1-1Y alloy powder was sprayed as a bond in each case before the final coating. The degradation behavior of the bared and coated steels was studied in the platen superheater of the coal-fired boiler. The samples were inserted through the soot blower dummy points with the help of stainless steel wires. The coatings were found to be effective in increasing resistance to degradation in the given boiler environment. The maximum protection was observed in the case of Stellite-6 (St-6) coating.

  16. Failure problems in superheater spacers of steam generators; Problematica de fallas en espaciadores de sobrecalentadores de generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Chacon Nava, Jose G.; Martinez Villafane, Alberto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Fuentes Samaniego, Raul [Universidad Autonoma de Nuevo Leon (Mexico); Mojica Calderon, Cecilio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    In this article the general aspects of the steam generator superheater fixed spacers failures are analyzed, emphasis is made on the influence several aspects such as the operation of the unit have, the appropriate execution of welds and the selection of binding materials. Likewise several recommendations are made to bring the failures to a minimum. [Espanol] En este articulo se analizan aspectos generales de fallas en espaciadores fijos de sobrecalentadores de generadores de vapor, y se hace hincapie en la influencia que tienen diversos aspectos tales como la operacion de la unidad, la adecuada ejecucion de soldaduras y la seleccion del material de aporte. Asimismo, se proponen algunas recomendaciones para reducir al minimo las fallas.

  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. Numerical and experimental study on heat pump water heater with PCM for thermal storage

    Energy Technology Data Exchange (ETDEWEB)

    Long, Jian-You; Zhu, Dong-Sheng [Key Laboratory of Enhanced Heat Transfer and Energy Conservation of the Ministry of Education, Academy of Chemistry and Energy, South China University of Technology, Guangzhou, Guangdong 510640 (China)

    2008-07-01

    An air source heat pump water heater with phase change material (PCM) for thermal storage was designed to take advantage of off-peak electrical energy. The heat transfer model of PCM was based upon a pure conduction formulation. Quasi-steady state method was used to calculate the temperature distribution and phase front location of PCM during thermal storage process. Temperature and thermal resistance iteration approach has been developed for the analysis of temperature variation of heat transfer fluid (HTF) and phase front location of PCM during thermal release process. To test the physical validity of the calculational results, experimental studies about storing heat and releasing heat of PCM were carried. Comparison between the calculational results and the experimental data shows good agreement. Graphical results including system pressure and input power of heat pump, time-wise variation of stored and released thermal energy of PCM were presented and discussed. (author)

  19. 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 ...

  20. Characteristics Evaluation of a CO2-Caputuring Power Generation System with Reheat Cycle Utilizing Regenerative Oxygen-Combustion Steam-Superheater

    Science.gov (United States)

    Pak, Pyong Sik

    A new CO2-capturing power generation system is proposed that can be easily realized by applying conventional technologies. In the proposed system, the temperature of middle-pressure steam in a thermal power plant is raised by utilizing oxygen-combusting regenerative steam-superheater. The generated CO2 by combusting fuel in the superheater can be easily separated and captured from the exhaust gas at condenser outlet, and is liquefied. The superheated steam is used to drive a steam turbine power generation system. By adopting a high efficient combined cycle power generation system as an example, it has been shown that the proposed system can increase power output by 10.8%, decrease the CO2 emission amount of the total integrated system by 18.6% with power generation efficiency drop of 2.36% compared with the original power plant without CO2-capture, when superheated steam temperature is 750°C

  1. Influence of surface roughness and melt superheat on HDA process to form a tritium permeation barrier on RAFM steel

    Energy Technology Data Exchange (ETDEWEB)

    Purushothaman, J. [B.S. Abdur Rahman University, Chennai 600048 (India); MTD, MMG, IGCAR, Kalpakkam 603102 (India); Ramaseshan, R., E-mail: seshan@igcar.gov.in [TFCS, SND, MSG, IGCAR, Kalpakkam 603102 (India); Albert, S.K. [MTD, MMG, IGCAR, Kalpakkam 603102 (India); Rajendran, R. [B.S. Abdur Rahman University, Chennai 600048 (India); Gowrishankar, N. [IP Rings Ltd., Maraimalainagar, Chennai 603209 (India); Ramasubbu, V. [MTD, MMG, IGCAR, Kalpakkam 603102 (India); Murugesan, S.; Dasgupta, Arup [PMG, MMG, IGCAR, Kalpakkam 603102 (India); Jayakumar, T. [MTD, MMG, IGCAR, Kalpakkam 603102 (India)

    2015-12-15

    Highlights: • Surface modified RAFMS samples were subjected to HDA and thermal oxidation. • Sample modified by SB process showed better coating and interface morphology. • Aluminized samples at 740 °C for 2 min showed Fe{sub 2}Al{sub 9}Si{sub 2} intermetallic phase. • Oxidized samples showed Fe{sub 2}Al{sub 8}Si, Fe{sub 2}Al{sub 3}Si{sub 3} and Fe{sub 3}Al{sub 2}Si{sub 3} intermetallic phases. • A uniform permeation barrier Al{sub 2}O{sub 3} was formed on the coating of oxidized HDA samples. - Abstract: The most optimal candidate material for fabrication of Test Blanket Module (TBM) in the installation of ITER and future fusion reactors is Reduced Activation Ferritic Martensitic (RAFM) steel, yet one of the major challenges that need to be addressed with RAFM is minimizing the loss of tritium in a reactor environment through the formation of tritium permeation barrier. One of the most promising methods for the tritium permeation barrier is through duplex coating with Al{sub 2}O{sub 3}/Fe–Al which is well known to reduce tritium permeation rate by several orders of magnitude. The present work aims to form an alumina layer on RAFM steel by a two-step method, which consists of (i) Hot Dip Aluminizing (HDA) and (ii) conversion of Al into alumina by a subsequent oxidation process. In addition, the influence of surface roughness of the substrate, superheat condition of the Al alloy melt and its composition on microstructural properties of coating before and after oxidation were investigated using OM, SEM–EDS, XRD, indentation micro hardness and scratch test. The experimental results confirmed the formation of alumina layer on RAFM steel after the HDA and oxidation process. Moreover, the surface roughness of the substrate, melt superheat of Al alloy and its composition are found to have a significant influence on the microstructure, thickness, micro-hardness, nature of intermetallic compounds formed and adhesion strength of the coating.

  2. The Effects of Wet Compression by the Electronic Expansion Valve Opening on the Performance of a Heat Pump System

    Directory of Open Access Journals (Sweden)

    Kyoungjin Seong

    2017-03-01

    Full Text Available In this study, by controlling the Electronic Expansion Valve opening, the influence of wet compression on a heat pump system was experimentally investigated in different heating conditions. The results demonstrate that the discharge temperature decreased and the mass flow rate increased, due to quality of the rising liquid droplets. It was also found that the heating capacity and power input of wet compression increased more than that of dry compression, with a superheat of 10 °C. The maximum COP (Coefficient of Performance exists at a specific quality of ca. 0.94 to 0.90, as the power input in the region of wet compression is proportionally larger than the increase in the heating capacity, according to the decreasing quality. When the Entering Water Temperature of the Outdoor Heat Exchanger was 10 °C, 5 °C, and 0 °C, the COP increased by a maximum of ca. 12.4%, 10.6%, and 10.2%, respectively, in comparison to the superheat of 10 °C. In addition, the superheat at the discharge line is proposed as a proper controlling parameter to adjust the quality at the suction line, by varying the opening of the expansion valve during wet compression.

  3. Effects of Degree of Superheat on the Running Performance of an Organic Rankine Cycle (ORC Waste Heat Recovery System for Diesel Engines under Various Operating Conditions

    Directory of Open Access Journals (Sweden)

    Kai Yang

    2014-04-01

    Full Text Available This study analyzed the variation law of engine exhaust energy under various operating conditions to improve the thermal efficiency and fuel economy of diesel engines. An organic Rankine cycle (ORC waste heat recovery system with internal heat exchanger (IHE was designed to recover waste heat from the diesel engine exhaust. The zeotropic mixture R416A was used as the working fluid for the ORC. Three evaluation indexes were presented as follows: waste heat recovery efficiency (WHRE, engine thermal efficiency increasing ratio (ETEIR, and output energy density of working fluid (OEDWF. In terms of various operating conditions of the diesel engine, this study investigated the variation tendencies of the running performances of the ORC waste heat recovery system and the effects of the degree of superheat on the running performance of the ORC waste heat recovery system through theoretical calculations. The research findings showed that the net power output, WHRE, and ETEIR of the ORC waste heat recovery system reach their maxima when the degree of superheat is 40 K, engine speed is 2200 r/min, and engine torque is 1200 N·m. OEDWF gradually increases with the increase in the degree of superheat, which indicates that the required mass flow rate of R416A decreases for a certain net power output, thereby significantly decreasing the risk of environmental pollution.

  4. Influence of Electronic Expansion Valve on Evaporator Superheat Stability%电子膨胀阀对蒸发器过热度稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    章晓龙; 李征涛; 陈忆; 高联斌

    2014-01-01

    为研究电子膨胀阀对蒸发器过热度稳定性的影响,建立了一套制冷系统控制试验台,试验得出电子膨胀阀的最小稳态过热度曲线,并在动态响应试验中得出蒸发器增益与时间常数、延迟时间与蒸发温度和过热度的关联性,从而为电子膨胀阀的控制优化提供参考。%To research the EEV’s effect on the stability of the evaporator superheat,the refrigeration control system experiment is built.The experiment show that the EEV has its own minimum steady-state superheat curve,and the dynamic response experi-ment gets the relationship between the evaporator gain,time constant,delay time and evaporating temprature,superheat,then it helps to built the better contol system of EEV.

  5. Heat-pump-assisted dryer: Pt. 2; Experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Pendyala, V.R.; Devotta, S.; Patwardhan, V.S. (National Chemical Lab., Poona (India))

    1990-07-01

    The performance of an experimental heat-pump-assisted dryer under operating conditions of some practical interest was studied. The system was operated using R11 and R12. The approach velocity of air to the evaporator and the superheat of the working fluid at the exit of the evaporator were identified as the critical parameters for optimization. The system was evaluated with respect to coefficient of performance (COP) and specific energy consumption (SEC). The (COP){sub A} and (SEC) values obtained using R11 were 3.5 and 3500 kJ/kg, respectively, and the corresponding values for R12 were 2.5 and 1800 kJ/kg. In spite of the lower (COP){sub A} for R12, the corresponding (SEC) values were better because the system could be operated without any additional electrical heating with R12. (author).

  6. 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

  7. 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: ...

  8. 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

  9. A novel combined approach based on HTF-Microbi.Array and qPCR for a reliable characterization of the Bifidobacterium-dominated gut microbiota of breast-fed infants.

    Science.gov (United States)

    Centanni, Manuela; Turroni, Silvia; Biagi, Elena; Severgnini, Marco; Consolandi, Clarissa; Brigidi, Patrizia; Candela, Marco

    2013-06-01

    The High Taxonomic Fingerprint (HTF)-Microbi.Array is a fully validated phylogenetic microarray platform for a high taxonomic level characterization of the human gut microbiota. However, suffering from PCR-dependent biases in Bifidobacterium quantification, this tool is less appropriate when utilized for the characterization of the Bifidobacterium-dominated gut microbiota of breast-fed infants. To overcome this, we implemented a new combined approach based on HTF-Microbi.Array and qPCR for a reliable fingerprint of the infant-type microbiota. This methodology was applied in a preliminary comparative study of the faecal microbiota of eight breast-fed infants, aged 2-6 months, and five young adults. Whereas the adult gut microbiota was largely dominated by Firmicutes and Bacteroidetes, the infant-type community was mainly dominated by Bifidobacterium, with Enterobacteriaceae as the second dominant component. In accordance with the most recent literature in the field, the obtained microbiota fingerprints properly depicted the adult- and the infant-type microbiota, demonstrating the reliability of the HTF-Microbi.Array/qPCR combined approach in reflecting the peculiarities of the two intestinal microbial ecosystems. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  10. Application of Smith Controller in Superheater Steam Temperature Control%Smith预估器在过热气温控制中的应用

    Institute of Scientific and Technical Information of China (English)

    于海东; 孙建国; 刘翠兰

    2012-01-01

    To the time-delay control process,the principle of Smith predictor is introduced and analyzed. The new structure of a modified Smith predictor is given particularly. Based on the ITAE criteria, the tuning method of the modified Smith controller's parameters are introduced. Combine with Dalate Power plant #4 unit superheater steam temperature control to inquiry into test method of parameter of Smith controller controlling superheater steam temperature > and carried on comparison and tally up on effect after implementation and normal PID control effect.%针对过程控制滞后的问题,介绍Smith预估器的控制原理和应用,把一种改进的Smith预估控制器应用于发电厂过热气温控制.并利用ITAE优化准则给出了改进Smith预估控制器的参数整定方法.以达拉特发电厂#4机组过热汽温控制为例探讨Smith预估器对过热汽温控制时参数的整定方法,并对实施后的效果与常规PID控制效果进行比较和总结.

  11. 蒸汽过滤器疲劳强度与寿命分析%Fatigue Strength and Life Analysis of Steam Superheater

    Institute of Scientific and Technical Information of China (English)

    赵静; 靳慧

    2015-01-01

    The steam superheater is a kind of pressure vessel which heats the steam from the saturation temperature to the superheat temperature in the boiler steam.The equipment was designed by ASME code,the test was done under 7.1 MPa of hydrostatic pressure in the normal temperature to ensure the bearing capacity.But the working temperature of the steam superheater is about 350 ℃ and the elastic modulus and yield stress would change a lot.The test at working temperature are difficult to realize.The safety and reliability cannot be guaranteed only rely on the experimental research at room temperature. Now the finite element calculations can simulate more condition and can guarantee the safety of steam generator.The steam superheater which is from a synthetic ammonia plant were taken as object of study. The three dimensional elastic-plastic finite element model of steam superheater was established,the dis-placement deformation of the intersection line between the nozzle and cylinder was presented by ANSYS calculating and compared with the experimental results,which verified that the finite element model can be used;Then the steam filter under the real operating conditions was simulated by finite element method, stress distribution and fatigue strength of open hole area were obtained;At last,fatigue evaluation results were compared between ANSYS fatigue calculation result(ASME Ⅷ -2)and the calculation result based on the Rssian Federation national standard ГОСТР25859.%蒸汽过热器是将蒸汽从饱和温度进一步加热至过热温度的一种压力容器。该设备是根据ASME 规范设计,在常温7.1 MPa 静水压力下经过测试确保轴承的能力。但蒸汽过热器的工作温度约为350℃,弹性模量和屈服应力都会发生很大的变化,在工作温度下的试验难于实现,此时可以借助有限元分析软件提供参考。对某20万吨合成氨厂的蒸汽过热器大开孔壳体建立了三维弹塑性有限元模型,

  12. 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.

  13. 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

  14. Comparison of tegaserod (HTF 919) and its main human metabolite with cisapride and erythromycin on cardiac repolarization in the isolated rabbit heart.

    Science.gov (United States)

    Drici, M D; Ebert, S N; Wang, W X; Rodriguez, I; Liu, X K; Whitfield, B H; Woosley, R L

    1999-07-01

    Tegaserod (HTF 919) is a new drug being developed for gastrointestinal motility disorders. Because other gastrointestinal prokinetic agents, such as cisapride and erythromycin, cause slowing of cardiac repolarization and have been implicated in the development of the potentially fatal ventricular arrhythmia, torsades de pointes, a study was initiated to determine whether tegaserod and its main human metabolite adversely influence cardiac repolarization. By using isolated Langendorff-perfused rabbit hearts, we show that QT intervals remain unchanged at concentrations of tegaserod from 0.5 to 10 microM. It was not until the tegaserod concentration was increased to 50 microM (roughly 500-5,000 times more concentrated than those typically found in human plasma after administration of recommended clinical dosages), that a small, but significant increase in the QT interval (12+/-4%; p 70%, respectively; p < 0.01; n = 4). Erythromycin also caused significant lengthening of QT intervals (11+/-2%; p < 0.001; n = 4), although 100 microM concentrations of this drug were required to achieve this effect. These results demonstrate that both cisapride and erythromycin can slow cardiac repolarization at therapeutic doses and that tegaserod's lack of QT prolongation at therapeutic doses suggests that it has the potential to be a safer alternative to cisapride as a gastrointestinal prokinetic agent.

  15. 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.

  16. 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

  17. High-Temperature Behavior of a NiCr-Coated T91 Boiler Steel in the Platen Superheater of Coal-Fired Boiler

    Science.gov (United States)

    Chatha, Sukhpal Singh; Sidhu, Hazoor S.; Sidhu, Buta S.

    2013-06-01

    Ni-20Cr coating was deposited on T91 boiler tube steel by high-velocity oxy-fuel (HVOF) process to enhance high-temperature oxidation resistance. High-temperature performance of bare, as well as HVOF-coated steel specimens was evaluated for 1500 h under in the platen superheater zone of coal-fired boiler, where the temperature was around 900 °C. Experiments were carried out for 15 cycles, each of 100-h duration followed by 1-h cooling at ambient temperature. The extent of degradation of the specimens was assessed by the thickness loss and depth of internal corrosion attack. Ni-20Cr-coated steel performed better than the uncoated steel in actual boiler environment. The improved degradation resistance of Ni-20Cr coating can be attributed to the presence of Cr2O3 in the top oxide scale and dense microstructure.

  18. Theoretical study of heat pump system using CO2/dimethylether as refrigerant

    Directory of Open Access Journals (Sweden)

    Fan Xiao-Wei

    2013-01-01

    Full Text Available Nowadays, HCFC22 is widely used in heat pump systems in China, which should be phased out in the future. Thus, eco-friendly mixture CO2/dimethylether is proposed to replace HCFC22. Compared with pure CO2 and pure dimethylether, the mixture can reduce the heat rejection pressure, and suppress the flammability and explosivity of pure dimethylether. According to the Chinese National Standards on heat pump water heater and space heating system, performances of the subcritical heat pump system are discussed and compared with those of the HCFC22 system. It can be concluded that CO2 /dimethylether mixture works efficiently as a refrigerant for heat pumps with a large heat-sink temperature rise. When mass fraction of dimethylether is increased, the heat rejection pressure is reduced. Under the nominal working condition, there is an optimal mixture mass fraction of 28/72 of CO2/dimethylether for water heater application under conventional condensation pressure, 3/97 for space heating application. For water heater application, both the heating coefficient of performance and volumetric heating capacity increase by 17.90% and 2.74%, respectively, compared with those of HCFC22 systems. For space heating application, the heating coefficient of performance increases by 8.44% while volumetric heating capacity decreases by 34.76%, compared with those of HCFC22 systems. As the superheat degree increases, both the heating coefficient of performance and volumetric heating capacity tend to decrease.

  19. 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.

  20. 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.

  1. 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...

  2. 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 ...

  3. 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.

  4. Genetic expression of hexokinase and glucose phosphate isomerase in late-stage mouse preimplantation embryos: transcription activities in glucose/phosphate-containing HTF and glucose/phosphate-free P1 media.

    Science.gov (United States)

    Johnson, M D; Batey, D W; Behr, B; Barro, J

    1997-04-01

    In mouse and human preimplantation development, pyruvate is consumed preferentially during early embryogenesis; however, during the morula and blastocyst stages, glucose is the preferred energy substrate. Studies have suggested that the glycolytic enzymes, hexokinase and glucose phosphate isomerase, are important enzymes in glucose metabolism during these later stages of human and mouse preimplantation development. In order to investigate the genetic activities of these enzymes in late-stage mouse embryos developing in vitro, we analysed hexokinase and glucose phosphate isomerase transcription activities by qualitative RNA assays using reverse transcriptase-nested polymerase chain reaction amplification of individual mouse morulae and early blastocysts incubated in glucose/phosphate-free preimplantation stage one (P1) medium and glucose/phosphate-containing human tubal fluid (HTF) medium. We observed an increased incidence of hexokinase transcripts in the population of blastocysts compared with morulae, and differences in transcript incidence between early blastocysts developing in HTF medium and in P1 medium. In contrast, glucose phosphate isomerase transcripts were consistantly present in all embryos analysed, and appear to be constitutively expressed during late-stage mouse embryogenesis. The different activity patterns of the two glycolytic genes may reflect different mechanisms of gene regulation or differential transcript stability during the later stages of mouse preimplantation development.

  5. Prediction of wall temperature diversification of superheater and reheater tubes%过热器/再热器管道壁面温度的预测

    Institute of Scientific and Technical Information of China (English)

    徐鸿; 赵志渊; 林振娴

    2011-01-01

    为了得到过热器/再热器管壁温度分布特性,通过对过热器/再热器管道的传热过程进行研究,并与经验公式相结合建立具有氧化膜的炉管传热的物理模型.分析在不同的管道几何尺寸、烟气温度、蒸汽流量和温度的情况下,管道外壁温度、氧化层/基体界面温度和氧化层/蒸汽界面温度的变化过程,最后定量地解释管道外壁温度、氧化膜/基体温度随运行时间增长而升高的原因,得到了它们的温升系数Aw和以与氧化层引起的温升系数B之间的关系为:B=α1Aw+α2An(其中,α1和α2分别为管外壁、氧化层/基体界面对氧化膜增长的敏感程度).%In order to get the wall temperature distribution characteristics of superheater/reheater tubes, a heat-transfer physical model of tubes with the oxide film was established by studying the heat transfer process of superheater/reheater tubes and the empirical formula. The temperature changing processes of tube outer-wall, the oxide scale/substrate interface and the oxide scale/steam interface were analyzed at different tube geometries, gas temperatures, steam flows, pressures and temperatures. Finally, the reason why the tube outer-wall temperature and the oxide scale/substrate interface temperature increase with the increase of the running time is quantitative interpreted, and the relationship between Av, An and B is as follows: 5 = a1Aw +a2A, in which a, and a2 represent the sensitivity of tube outer-wall and the interface between oxide scale and substrate to the growth of oxide scale.

  6. Analysis of Tank 38H (HTF-38-15-119, 127) Surface, Subsurface and Tank 43H (HTF-43-15-116, 117 and 118) Surface, Feed Pump Suction and Jet Suction Subsurface Supernatant Samples in Support of Enrichment, Corrosion Control and Salt Batch Planning Programs

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-12-17

    Compositional feed limits have been established to ensure that a nuclear criticality event for the 2H and 3H Evaporators is not possible. The Enrichment Control Program (ECP) requires feed sampling to determine the equivalent enriched uranium content prior to transfer of waste other than recycle transfers (requires sampling to determine the equivalent enriched uranium at two locations in Tanks 38H and 43H every 26 weeks) The Corrosion Control Program (CCP) establishes concentration and temperature limits for key constituents and periodic sampling and analysis to confirm that waste supernate is within these limits. This report provides the results of analyses on Tanks 38H and 43H surface and subsurface supernatant liquid samples in support of the ECP, the CCP, and the Salt Batch 10 Planning Program.

  7. State feedback controller with subordinate mass flow control as optimized temperature control for superheaters; Zustandsregler mit unterlagerter Massenstrom-Regelung als optimierte Temperaturregelung fuer einen Ueberhitzer

    Energy Technology Data Exchange (ETDEWEB)

    Bienert, W. [Kraftwerk Pleinting der Bayernwerk AG Konventionelle Waermekraftwerke GmbH (Germany). Abt. Elektro- und Leittechnik; Mann, J. [Siemens AG, Karlsruhe (Germany). Bereich Energieerzeugung (KWU)

    1998-12-31

    During a boiler construction change at the power station Pleinting Unit 2 the heating surfaces of the superheater were enlarged. Due to these changes in the temperature control loop, the temperature deviations could no longer be regulated satisfactorily by the hitherto installed conventional controllers. Using state feedback controllers thereafter, these deviations were reduced considerably. The configuring and parameter setting of the used state feedback controllers was extremely easy because only one tuning factor was needed. So further optimizations with customer benefits could be worked out: The state feedback control was supplemented by an enthalpy calculation with subordinate mass flow control. Thus, it has become possible to inject water into saturated steam during start-ups in case of high temperature deviations. The achieved results are verified by time trends measured at the plant. (orig.) [Deutsch] Bei einem Kesselumbau im Kraftwerk Pleinting Block 2 wurden die Heizflaechen der Ueberhitzer und damit die Aufwaermspannen vergroessert. Aufgrund der dadurch veraenderten Temperaturregelstrecke konnten die Temperaturstoerungen mit der konventionellen Regelung nicht mehr zufriedenstellend ausgeregelt werden. Mit dem Einsatz von Zustandsreglern wurden diese Regelabweichungen wesentlich verringert. Die Projektierung und Parametrierung der verwendeten Zustandsregler gestaltete sich durch die Verwendung von nur einem Einstellfaktor aeusserst einfach. So konnte dann das Augenmerk auf weiteres Optimierungspotential mit Kundennutzen gelegt werden: Die Zustandsregelung wurde um eine Enthalpie-Rechnung mit unterlagerter Massenstromregelung ergaenzt, um waehrend des Anfahrens bei hohen Temperaturbweichungen in Sattdampf einspritzen zu koennen. Die erzielten Ergebnisse sind durch in der Anlage gemessene Kurven belegt. (orig.)

  8. Influence of Melt Superheat, Sr Modifier, and Al-5Ti-1B Grain Refiner on Microstructural Evolution of Secondary Al-Si-Cu Alloys

    Science.gov (United States)

    Rakhmonov, Jovid; Timelli, Giulio; Bonollo, Franco

    2016-11-01

    The role of impurity elements and melt superheat on the efficiency of Sr modification, grain refinement with Al-Ti-B and the precipitation behavior of intermetallic phases in a secondary Al-7Si-3Cu-0.3Mg alloy were investigated. Metallographic and thermal analysis techniques were used to quantitatively examine the macro- and microstructural changes occurring with modifier and grain refiner additions at various pouring temperatures. The results indicate how the Sr modification and grain refinement with Al-Ti-B can be effective enough despite the presence of impurity elements in the material and the variation of pouring temperature. A slight poisonous effect of impurities, in particular, Zr and V, in the grain refinement efficiency can be eventually induced due to their action in promoting the formation of primary AlSiTi compounds. Moreover, grain refiner addition exerted a pronounced influence on the precipitation sequence of Fe-rich phases. The TiB2 particles appeared to promote the formation of Al5FeSi during solidification by acting as a favorable nucleation site.

  9. Properties of thick welded joints on superheater collectors made from new generation high alloy martensitic creep-resisting steels for supercritical parameters

    Energy Technology Data Exchange (ETDEWEB)

    Dobrzanski, Janusz; Zielinski, Adam [Institute for Ferrous Metallurgy, Gliwice (Poland); Pasternak, Jerzy [Boiler Engineering Company RAFAKO S.A., Raciborz (Poland)

    2010-07-01

    The continuously developing power generation sector, including boilers with supercritical parameters, requires applications of new creep-resistant steel grades for construction of boilers steam superheater components. This paper presents selected information, experience within the field of research and implementation of a new group of creep-resistant as X10CrMoVNb9-1(P91), X10CrWMoVNb9-2(P92) and X12CrCoWVNb12-2-2(VM12) grades, containing 9-12%Cr. During welding and examination process the results of mechanical properties, requested level for base material and welded joints, as well as: tensile strength, impact strength and technological properties have been evaluated. Additional destructive examinations, with evaluation of structure stability, hardness distribution, for base material and welded joints after welding, heat treatment, again process have been determined. Recommendations due to the implementation influence of operating parameters of the main boiler components are part of this paper. (orig.)

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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)

  16. 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...

  17. 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.

  18. 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…

  19. 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...

  20. 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

  1. 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....

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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...

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 某电厂锅炉前屏过热器爆管原因分析及处理%The Cause Analysis and Processing for Tube Explosion of the Boiler’s Front Platen Superheater

    Institute of Scientific and Technical Information of China (English)

    毛民·阿斯哈尔

    2015-01-01

    During the operation of the power plant boiler, the leakage of four kinds of tubes in the boiler (economizer tube, water cooling wal tube, superheater tube and reheater tube) is the main cause of the unplanned outage. So, to prevent the leakage and explosion of boiler is significant for ensuring safely and economical operation of the generator unit. In this paper, the cause, processing and preventive measures for the tube explosion of the boiler’s front platen superheater are analyzed.%在电站锅炉运行中,锅炉四管(省煤器,水冷壁,过热器,再热器)的泄漏是造成机组非计划停运的主要原因,由此可见认真做好防止锅炉受热面的泄漏和爆破工作,对保证机组安全稳定经济运行是十分关键的。本文主要分析引起某电厂锅炉前屏过热器爆破的原因、处理及应该采取的预防措施。

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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)

  9. 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.

  10. 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.

  11. 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...

  12. Development on Performance Testing System of Superheat-resisting Canned Motor Pump without Hydrocooling%屏蔽泵性能测试的自动化控制系统

    Institute of Scientific and Technical Information of China (English)

    王兆福; 王新华; 李剑峰; 董新蕊; 刘春波; 马永超

    2007-01-01

    针对无水冷超耐热屏蔽电泵的工作特性,研制开发了屏蔽电泵性能实验装置及测试系统,简述了测试系统的组成及主要功能模块.详细介绍了性能参数的测量方法及传感器选型依据,介绍了测试系统的数据采集、输出控制、数据传输和I/O通信等功能模块的实现方法及编程思想.实验表明,开发的测试系统能够很方便地实现屏蔽电泵性能实验的数据采集、存储、处理、输出控制、曲线绘制、报表生成、打印等功能,从而实现了屏蔽电泵性能测试的微机化和信息化,大大提高了屏蔽电泵性能实验的效率和可靠性,满足了屏蔽电泵实际生产的需要.

  13. 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.

  14. 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...

  15. 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.

  16. 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)

  17. 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

  18. 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...

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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 ...

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Advanced exergy analysis of transcritical CO2 heat pump system based on experimental data

    Indian Academy of Sciences (India)

    JAHAR SARKAR; DNYANESH JOSHI

    2016-11-01

    Conventional exergy analysis identifies component exergy destruction, however, does not give clear picture whether occurs because of component itself or due to remaining components and then the advanced exergy analysis is emphasized. The main purpose of this study is to apply advanced exergy analysis to the transcritical CO2 vapor compression heat pump system for simultaneous water cooling and heating, along withthe conventional exergy analysis. The novelty of the present study is the advanced exergy analysis (with modified methodology) of transcritical superheat cycle based on experimental data. Endogenous, exogenous, avoidable and unavoidable exergy destructions are determined for each component of this system. Results showthat compressor is having highest exergy destruction among the CO2system components and also its major partis avoidable endogenous exergy destruction. According to conventional exergy analysis, the sequence for improvement seems to be compressor, gas cooler, expansion valve and evaporator; however, the in-depthanalysis (advanced exergy analysis) shows compressor is the first component followed by evaporator, gas cooler and expansion valve to be considered for improvisation. Thus it is concluded that compressor provides highest opportunity for improvement and new design of the same will improve overall transcritical CO2 system performance.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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.

  2. 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.

  3. 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...

  4. 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....

  5. 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.

  6. 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...

  7. 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)....

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. [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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.).

  18. 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.

  19. 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.

  20. 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.

  1. 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)

  2. Assessment methodology of power station boiler superheater based on risk-based inspection technology%基于风险检验技术的电站锅炉过热器评定方法

    Institute of Scientific and Technical Information of China (English)

    刘富君; 孔帅; 凌张伟; 郑慕林; 钱岳强; 金南辉; 王强; 李翔

    2011-01-01

    The risk assessment methodology based on risk-based inspection (RBI) was analyzed in order to evaluate the risk situation of the power station boiler superheater to establish the reasonable management, and maintenance strategy and reduce the non-plan shutdowns. The failure mechanism of power station boiler was analyzed, and the creep damage factor computing technical module and high-temperature smoke erosion thinning technical module for power station boiler tubes were conducted. The failure probability correction factor was presented based on the remaining life, considering China's national condition, including the extended service and initial material defects etc. Moreover, the proper financial risk calculation method was established to assess the risk consequence, and the grade distinguish rule was established. The risk level was evaluated through the failure possibility and consequence quantitative analysis and calculation of a superheater, and the reasonable management and maintenance strategy was established.%为了科学评价电站锅炉过热器的风险状况,制定合理的管理和维护策略,减少非计划停炉,研究基于风险检验(RBI)技术的过热器风险评定方法.研究过热器炉管的失效机理,建立适用于过热器炉管的高温烟气冲蚀因子和高温蠕变因子计算方法;结合我国超期服役、炉管材料初始缺陷等情况,提出基于剩余寿命参量的失效可能性修正系数;进一步确定合理的经济损失法来计算炉管失效后果,建立失效后果等级划分准则.通过对某末级过热器炉管失效的可能性和失效后果进行定量分析和计算,评定了炉管风险等级,制定了合理的管理和维护策略.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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...

  9. 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.

  10. 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.

  11. 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....

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 涡旋式水源热泵系统性能仿真%Performance Simulation of Scroll Water Source Heat Pump System

    Institute of Scientific and Technical Information of China (English)

    汤志远; 丁国良

    2011-01-01

    为了预测涡旋式水源热泵系统变结构和变工况稳态性能,建立了稳态涡旋式热泵系统仿真模型.其中涡旋式压缩机模型考虑了吸、排气换热对工质流量和排气温度的影响以及流量、排气温度和输入功率三者的耦合关系;通过增加电子膨胀阀开度对蒸发器出口过热度的控制模型,反映了过热度对膨胀阀流量的影响.系统算法综合了顺序模块法和连续迭代法,改善了迭代收敛性,且易于实现部件模型的模块化.与实验结果对比表明:模型预测值与实验值的误差小于4.4%.%To predict the steady performance of scroll water source heat pumps with different configuration and working condition a steady systematic model for scroll water source heat pump is established. In modeling the compressor, the effect of suction heatin on mass flow and the effect of discharge heat exchange on discharge temperature as well as coupling relationship between mas flow, discharge temperature and input power are considered. The effect of the superheat of evaporator on the mass flow through tfc electrical expansion valve (EEV) is reflected by the control model of EEV opening degree on the superheat of evaporator. Successrv Substitution Method and Sequential Modular Method are used in the system simulation, which is 'in favor of modulization an maintainability of components, as well as convergence of algorithm. The deviations between the model predictions and the test dai are less than 4.4%.

  17. 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.

  18. 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.

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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...

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Performance evaluation of a vapor compression heat pump cycle using binary zeotropic refrigerant mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Shigeru; Yara, Tomoyasu

    1999-07-01

    The HCFC refrigerants such as R22 have been used widely as working fluids in refrigeration and air-conditioning systems until now. These refrigerants, however, should be phased out early in the next century to prevent the depletion of the ozone layer. In this situation, binary and/or ternary mixtures composed of HFC and/or natural refrigerants have attracted a great deal of attention due to the following possibilities: (1) to improve the coefficient of performance, COP, by utilizing the temperature glide during phase change processes; (2) to keep the system in more suitable condition for given temperature levels of heat source and heat sink by selecting the combination and composition of refrigerants, etc. From this point of view, in the present study, the performance prediction of a vapor compression heat pump cycle using binary zeotropic refrigerant mixtures is carried out to clarify the effects of the combination of refrigerants, the composition of refrigerants and the size of heat exchangers on COP. In the prediction calculation, a vapor compression heat pump cycle, which consists of a compressor, a vertical plate-fin condenser, an expansion valve, a liquid-vapor separator and a vertical plate-fin evaporator is treated, and the following assumptions are employed: (1) the compression process is isentropic, (2) the expansion process is isenthalpic, (3) the refrigerant is a saturated liquid at the condenser outlet and a superheated vapor at the evaporator outlet, (4) the pressure drop in the condenser is negligible, while that in the evaporator is considered, (5) the local heat transfer characteristics in heat exchangers are considered. The prediction calculation is done for the binary zeotropic refrigerant mixtures of HFC134a/HCFC123 on condition that the heat source water temperature at the condenser outlet, the heat sink water temperature at the evaporator inlet, the water temperature change through condenser and evaporator, the heat load of condenser, the

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. 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 ...

  10. 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...

  11. 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

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. [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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. [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.

  14. 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.

  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. 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.

  19. 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.

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. 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....

  5. 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}.

  6. 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,…

  7. 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.

  8. 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 ...

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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....

  16. 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....

  17. Rotating and positive-displacement pumps for low-thrust rocket engines. Volume 1: Pump Evaluation and design. [of centrifugal pumps

    Science.gov (United States)

    Macgregor, C.; Csomor, A.

    1974-01-01

    Rotating and positive displacement pumps of various types were studied for pumping liquid fluorine for low-thrust, high-performance rocket engines. Included in the analysis were: centrifugal, pitot, Barske, Tesla, drag, gear, vane, axial piston, radial piston, diaphragm, and helirotor pump concepts. The centrifugal pump and the gear pump were selected and these were carried through detailed design and fabrication. Mechanical difficulties were encountered with the gear pump during the preliminary tests in Freon-12. Further testing and development was therefore limited to the centrifugal pump. Tests on the centrifugal pump were conducted in Freon-12 to determine the hydrodynamic performance and in liquid fluorine to demonstrate chemical compatibility.

  18. Automation of a water pumping station

    OpenAIRE

    Mesec, Rožle

    2014-01-01

    In the thesis we displayed an automation of an industrial facility on an example of a water pumping station. We described the structure of a typical automated system and presented it's key components. We designed a water pumping station with three main components – a water pump, a reservoir and a drain. The proposed water pumping station could be used for suplying water to a small settlement, in case the settlement had access to a water source with adequate capacity in it's vicinity. As part ...

  19. Electricity Market Optimization of Heat Pump Portfolio

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Andersen, Palle; Pedersen, Tom S.

    2013-01-01

    We consider a portfolio of domestic heat pumps controlled by an aggregator. The aggregator is able to adjust the consumption of the heat pumps without affecting the comfort in the houses and uses this ability to shift the main consumption to hours with low electricity prices. Further, the aggrega......We consider a portfolio of domestic heat pumps controlled by an aggregator. The aggregator is able to adjust the consumption of the heat pumps without affecting the comfort in the houses and uses this ability to shift the main consumption to hours with low electricity prices. Further...

  20. Mechanical Blood Pumps for Cardiac Assistance

    Directory of Open Access Journals (Sweden)

    M. Akdis

    2005-01-01

    Full Text Available Cardiac assist devices are classified into the traditional engineering categories of displacement and rotary pumps. Clinical use and indications of the various pump categories are outlined and a detailed description of currently available systems is given. The first part deals with extracorporeal as well as implantable ventricular assist devices (VAD of the displacement type and is followed by a section on current developments in the field of total artificial hearts (TAH. The second part covers the rotary pump category from cardiopulmonary bypass applications to implantable systems, including specific design aspects of radial, diagonal, and axial pumps.

  1. Coating of pumps; coating af pumper

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Hans; Moritzen, J.; Thoegersen, Jeanette

    2005-11-15

    Coating of pumps is a quite new activity. For many years pipes and containers have been coated inside in order to avoid corrosion, but the technology has only been used inside pumps for the last ten years. The technology comes from USA and is originally developed in the space technology industry as an exceptionally durable and corrosion constant coating. The project is a further development of results found in a previous R and D project in which measurements were performed before and after coating two different installations. Both installations showed large efficiency improvements. This project supplements the theory behind losses in pumps with measurements on more pumps. (BA)

  2. [Insulin pump therapy: for whom and why?].

    Science.gov (United States)

    Saraheimo, Markku; Honkasalo, Mikko; Miettinen, Marko

    2013-01-01

    Insulin pump therapy utilizes continuous infusion for the basic supply of insulin. As compared with multiple daily injections, pump therapy enables a clearly more precise targeting of the insulin therapy with respect to both time and quantity. This is important for insulin-sensitive patients such as small children, adults susceptible to hypoglycemia, or diabetics, whose blood glucose level exhibits a clear-cut elevation in the small hours (the dawn phenomenon). Also a diabetic with a high HbA1c and a good motivation for treatment may significantly benefit from the pump. Insulin pump therapy requires commitment to good self-monitoring from the diabetic patient.

  3. Patient-controlled analgesic infusion pumps.

    Science.gov (United States)

    2001-05-01

    Patient-controlled analgesic (PCA) infusion devices allow patients to self-administer narcotic analgesics within the limits prescribed by the physician. PCA therapy is typically used for postoperative, obstetric, terminally ill, and trauma patients. PCA pumps deliver solutions intravenously, subcutaneously, or epidurally and allow patient activation by means of a pendant button on a cord connected to the pump or a button directly on the pump. We evaluated nine PCA pumps from six suppliers. Three of these pumps are syringe-type, while the others use cassette-based fluid delivery. Because PCA pumps have often been cited as examples of devices that contribute to medical error (the most significant risk connected with PCA infusion is overmedication), the accident resistance of each device weighed heavily in our testing. The pumps we tested exhibit varying levels of performance, resistance to accidents and tampering, and ease of use. We rate six of them Acceptable. While none of the six units stands out as ideal, they meet most of our criteria, and we consider them somewhat better choices than the rest. We rate one other pump Acceptable (with Conditions) because, in one of its operating modes, it has a drawback that could be dangerous to patients; we consider its use acceptable only if the hospital doesn't employ the operating mode in question. Finally, we rate two pumps Not Recommended because they both have a significant number of disadvantages.

  4. Absorption heat pump for space applications

    Science.gov (United States)

    Nguyen, Tuan; Simon, William E.; Warrier, Gopinath R.; Woramontri, Woranun

    1993-01-01

    In the first part, the performance of the Absorption Heat Pump (AHP) with water-sulfuric acid and water-magnesium chloride as two new refrigerant-absorbent fluid pairs was investigated. A model was proposed for the analysis of the new working pairs in a heat pump system, subject to different temperature lifts. Computer codes were developed to calculate the Coefficient of Performance (COP) of the system with the thermodynamic properties of the working fluids obtained from the literature. The study shows the potential of water-sulfuric acid as a satisfactory replacement for water-lithium bromide in the targeted temperature range. The performance of the AHP using water-magnesium chloride as refrigerant-absorbent pair does not compare well with those obtained using water-lithium bromide. The second part concentrated on the design and testing of a simple ElectroHydrodynamic (EHD) Pump. A theoretical design model based on continuum electromechanics was analyzed to predict the performance characteristics of the EHD pump to circulate the fluid in the absorption heat pump. A numerical method of solving the governing equations was established to predict the velocity profile, pressure - flow rate relationship and efficiency of the pump. The predicted operational characteristics of the EHD pump is comparable to that of turbomachinery hardware; however, the overall efficiency of the electromagnetic pump is much lower. An experimental investigation to verify the numerical results was conducted. The pressure - flow rate performance characteristics and overall efficiency of the pump obtained experimentally agree well with the theoretical model.

  5. MEMS ion-sorption high vacuum pump

    Science.gov (United States)

    Grzebyk, T.; Knapkiewicz, P.; Szyszka, P.; Gorecka-Drzazga, A.; Dziuban, J. A.

    2016-11-01

    In the article a miniature MEMS-type ion-sorption vacuum pump has been presented. The influence of electric and magnetic field, as well as horizontal and vertical dimensions of the micropump and type of material used for electrodes on the pump properties has been investigated. It has been found that the micropump works efficiently as long as the magnetic field is higher than 0.3 T, and pumping cell is larger than 1x1x1 mm3. The pump allows generating vacuum at the level of 10-7-10-9 hPa in 100 mm3 volume.

  6. Distribution of Pressure Fluctuations in a Prototype Pump Turbine at Pump Mode

    OpenAIRE

    Sun, Yuekun; Zuo, Zhigang; Liu, Shuhong; Liu, Jintao; Wu, Yulin

    2014-01-01

    Pressure fluctuations are very important characteristics in pump turbine’s operation. Many researches have focused on the characteristics (amplitude and frequencies) of pressure fluctuations at specific locations, but little researches mentioned the distribution of pressure fluctuations in a pump turbine. In this paper, 3D numerical simulations using SST k-ω turbulence model were carried out to predict the pressure fluctuations distribution in a prototype pump turbine at pump mode. Three oper...

  7. Proton pump inhibitors and osteoporosis

    DEFF Research Database (Denmark)

    Andersen, Bjarne Nesgaard; Johansen, Per Birger; Abrahamsen, Bo

    2016-01-01

    PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months and a di......PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months...... and a discussion of these findings and how this has influenced our understanding of this association, the clinical impact and the underlying pathophysiology. RECENT FINDINGS: New studies have further strengthened existing evidence linking use of PPIs to osteoporosis. Short-term use does not appear to pose a lower...... risk than long-term use. There is a continued lack of conclusive studies identifying the pathogenesis. Direct effects on calcium absorption or on osteoblast or osteoclast action cannot at present plausibly explain the mechanism. SUMMARY: The use of PPIs is a risk factor for development of osteoporosis...

  8. A regenerative elastocaloric heat pump

    Science.gov (United States)

    Tušek, Jaka; Engelbrecht, Kurt; Eriksen, Dan; Dall'Olio, Stefano; Tušek, Janez; Pryds, Nini

    2016-10-01

    A large fraction of global energy use is for refrigeration and air-conditioning, which could be decarbonized if efficient renewable energy technologies could be found. Vapour-compression technology remains the most widely used system to move heat up the temperature scale after more than 100 years; however, caloric-based technologies (those using the magnetocaloric, electrocaloric, barocaloric or elastocaloric effect) have recently shown a significant potential as alternatives to replace this technology due to high efficiency and the use of green solid-state refrigerants. Here, we report a regenerative elastocaloric heat pump that exhibits a temperature span of 15.3 K on the water side with a corresponding specific heating power up to 800 W kg-1 and maximum COP (coefficient-of-performance) values of up to 7. The efficiency and specific heating power of this device exceeds those of other devices based on caloric effects. These results open up the possibility of using the elastocaloric effect in various cooling and heat-pumping applications.

  9. 77 FR 2957 - Application for Manufacturing Authority, Liberty Pumps, Inc. (Submersible and Water Pumps...

    Science.gov (United States)

    2012-01-20

    ... Foreign-Trade Zones Board Application for Manufacturing Authority, Liberty Pumps, Inc. (Submersible and Water Pumps), Bergen, NY An application has been submitted to the Foreign-Trade Zones Board (the Board... manufacturing authority on behalf of Liberty Pumps, Inc., located in Bergen, New York. The application...

  10. 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.

  11. Root cause analysis of pump valve failures of three membrane pump systems

    NARCIS (Netherlands)

    Buijs, L.J.; Eijk, A.; Hooft, L. van

    2014-01-01

    This paper will present the root cause analysis and the solution of fatigue failures of the pump valves of three membrane pump systems installed on a chemical plant of Momentive in Pernis, the Netherlands. The membrane pumps were installed approximately 30 years ago. Each system has encountered fati

  12. Quantum pumping in graphene with a perpendicular magnetic field

    NARCIS (Netherlands)

    Tiwari, R.P.; Blaauboer, M.

    2010-01-01

    We consider quantum pumping of Dirac fermions in a monolayer of graphene in the presence of a perpendicular magnetic field in the central pumping region. The two external pump parameters are electrical voltages applied to the graphene sheet on either side of the pumping region. We analyze this pump

  13. Miniature Scroll Pumps Fabricated by LIGA

    Science.gov (United States)

    Wiberg, Dean; Shcheglov, Kirill; White, Victor; Bae, Sam

    2009-01-01

    Miniature scroll pumps have been proposed as roughing pumps (low - vacuum pumps) for miniature scientific instruments (e.g., portable mass spectrometers and gas analyzers) that depend on vacuum. The larger scroll pumps used as roughing pumps in some older vacuum systems are fabricated by conventional machining. Typically, such an older scroll pump includes (1) an electric motor with an eccentric shaft to generate orbital motion of a scroll and (2) conventional bearings to restrict the orbital motion to a circle. The proposed miniature scroll pumps would differ from the prior, larger ones in both design and fabrication. A miniature scroll pump would include two scrolls: one mounted on a stationary baseplate and one on a flexure stage (see figure). An electromagnetic actuator in the form of two pairs of voice coils in a push-pull configuration would make the flexure stage move in the desired circular orbit. The capacitance between the scrolls would be monitored to provide position (gap) feedback to a control system that would adjust the drive signals applied to the voice coils to maintain the circular orbit as needed for precise sealing of the scrolls. To minimize power consumption and maximize precision of control, the flexure stage would be driven at the frequency of its mechanical resonance. The miniaturization of these pumps would entail both operational and manufacturing tolerances of pump components. In addition, the vibrations of conventional motors and ball bearings exceed these tight tolerances by an order of magnitude. Therefore, the proposed pumps would be fabricated by the microfabrication method known by the German acronym LIGA ( lithographie, galvanoformung, abformung, which means lithography, electroforming, molding) because LIGA has been shown to be capable of providing the required tolerances at large aspect ratios.

  14. Unintended Insulin Pump Delivery in Hyperbaric Conditions.

    Science.gov (United States)

    Bertuzzi, Federico; Pintaudi, Basilio; Bonomo, Matteo; Garuti, Fabio

    2017-04-01

    Unintended pump insulin delivery was reported to occur as a consequence of decreased atmospheric pressure, probably mediated by air bubble formation and the expansion of existing bubbles. This observation has been used to explain some hypoglycemic episodes occurring in patients on insulin pump treatment in between 1 and 1 h 45 min after the flight takeoff. New models of insulin pumps have been introduced in the market, most of them are waterproof certified. It is not clear if in these new pumps the influence of atmospheric pressure changes on the insulin delivery is still present. Moreover, there are no evidences related to the insulin pump operations in hyperbaric conditions, like as during diving activities. Our aim is therefore to verify the eventual variation of insulin pump delivery determined by atmospheric pressure changes in hyperbaric conditions. Three new models of insulin pumps were tested in hyperbaric conditions at a flow rate of 2 U/h. Atmospheric pressure variation affected pump insulin release. An increase in the atmospheric pressure from 1 to 1.3 atmosphere (ATA) induced a decrease of pump basal insulin release (about -0.2 U/10 min); conversely, when the atmospheric pressure returned from 1.3 to 1 ATA, an unintended insulin delivery was observed (about +0.3 U/10 min). This phenomenon appeared to be independent of the insulin pump rate and dependent on the presence of air bubbles within the insulin tube setting and cartridge. Unintended insulin delivery driven by atmospheric pressure changes in hyperbaric conditions occurred in the new insulin pumps available. Patients should pay attention to possible variation of insulin rate during the flight or during diving activities.

  15. PV water pumping: NEOS Corporation recent PV water pumping activities

    Energy Technology Data Exchange (ETDEWEB)

    Lane, C.

    1995-11-01

    NEOS Corporation has been very active in PV-powered water pumping, particularly with respect to electric utilities. Most of the recent activity has been through the Photovoltaic Services Network (PSN). The PSN is an independent, not-for-profit organization comprised of all types of electric utilities: rural electric coops, public power districts, investor-owned utilities, and power marketing agencies. The PSN`s mission is to work pro-actively to promote utility involvement in PV through education and training. PV information is distributed by the PSN in three primary forms: (1) consultation with PSN technical service representatives: (2) literature generated by the PSN; and (3) literature published by other organizations. The PSN can also provide assistance to members in developing PV customer service programs. The PSN`s product support activities include consolidation of information on existing packaged PV systems and facilitation of the development of new PV product packages that meet utility-defined specifications for cost performance, and reliability. The PSN`s initial product support efforts will be focused on commercially available packaged PV systems for a variety of off-grid applications. In parallel with this effort, if no products exist that meet the PSN`s functional specifications, the PSN will initiate the second phase of product development support process by encouraging the development of new packaged systems. Through these services and product support activities, the PSN anticipates engaging all segments for the PV industry, thus providing benefits to PV systems suppliers as well as local PV service contractors.This paper describes field testing of pv power systems for water pumping.

  16. 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.

  17. A model of annular linear induction pumps

    Energy Technology Data Exchange (ETDEWEB)

    Momozaki, Yoichi [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-27

    The present work explains how the magnetic field and the induced current are obtained when the distributed coils are powered by a 3 phase power supply.  From the magnetic field and the induced current, the thrust and the induction losses in the pump can be calculated to estimate the pump performance.

  18. Space Station Water Processor Process Pump

    Science.gov (United States)

    Parker, David

    1995-01-01

    This report presents the results of the development program conducted under contract NAS8-38250-12 related to the International Space Station (ISS) Water Processor (WP) Process Pump. The results of the Process Pumps evaluation conducted on this program indicates that further development is required in order to achieve the performance and life requirements for the ISSWP.

  19. Fabrication of micro metallic valve and pump

    Science.gov (United States)

    Yang, Ming; Kabasawa, Yasunari; Ito, Kuniyoshi

    2010-03-01

    Fabrication of micro devices by using micro metal forming was proposed by the authors. We developed a desktop servo-press machine with precise tooling system. Precise press forming processes including micro forging and micro joining has been carried out in a progressive die. In this study, micro metallic valve and pump were fabricated by using the precise press forming. The components are made of sheet metals, and assembled in to a unit in the progressive die. A micro check-valve with a diameter of 3mm and a length of 3.2mm was fabricated, and the property of flow resistance was evaluated. The results show that the check valve has high property of leakage proof. Since the valve is a unit parts with dimensions of several millimeters, it has advantage to be adapted to various pump design. Here, two kinds of micro pumps with the check-valves were fabricated. One is diaphragm pump actuated by vibration of the diaphragm, and another is tube-shaped pump actuated by resonation. The flow quantities of the pumps were evaluated and the results show that both of the pumps have high pumping performance.

  20. low pump power photonic crystal fibre amplifiers

    DEFF Research Database (Denmark)

    Hougaard, Kristian G.; Broeng, Jes; Bjarklev, Anders Overgaard

    2003-01-01

    Designs of low pump power optical amplifiers, based on photonic crystal fibres are presented. The potential of these fibre amplifiers is investigated, and it is demonstrated that such amplifiers may deliver gains of more than 15 dB at 1550 nm with less than 1 mW of optical pump power....

  1. Pumps for medium sized solar systems

    DEFF Research Database (Denmark)

    Furbo, Simon

    1996-01-01

    The suitability of the electronically controlled circulation pump type UPE 2000 from Grundfos for large solar heating systems was elucidated.......The suitability of the electronically controlled circulation pump type UPE 2000 from Grundfos for large solar heating systems was elucidated....

  2. Fluid structure interaction in piston diaphragm pumps

    NARCIS (Netherlands)

    Van Rijswick, R.; Van Rhee, C.

    2013-01-01

    Piston diaphragm pumps are used world-wide for the transport of aggressive and/or abrasive fluids in the chemical, mining and mineral processing industries. Figure 1 shows a cross section of a piston diaphragm pump as is used in the mining and mineral processing industries for the transport of

  3. Dynamics of flatter wind pump installation

    Directory of Open Access Journals (Sweden)

    А. С. Крижановський

    1999-05-01

    Full Text Available Wind pump installation is considered, in which as quality wind engine is used flatter wind engine with vertically located wing blade. For research of dynamics of installation its mathematical model is constructed. Determined is the law of movement of wing blade at a connected load and main characteristics of wind pump installation

  4. Quantum pumping in a ballistic graphene bilayer

    NARCIS (Netherlands)

    Wakker, G.M.M.; Blaauboer, M.

    2010-01-01

    We investigate quantum pumping of massless Dirac fermions in an ideal (impurity free) double layer of graphene. The pumped current is generated by adiabatic variation in two gate voltages in the contact regions to a weakly doped double graphene sheet. At the Dirac point and for a wide bilayer with

  5. Materials for diode pumped solid state lasers

    Science.gov (United States)

    Chase, L. L.; Davis, L. E.; Krupke, W. F.; Payne, S. A.

    1991-07-01

    The advantages of semiconductor diode lasers and laser arrays as pump sources for solid state lasers are reviewed. The properties that are desirable in solid state laser media for various diode pumping applications are discussed, and the characteristics of several promising media are summarized.

  6. Cladding For Transversely-Pumped Laser Rod

    Science.gov (United States)

    Byer, Robert L.; Fan, Tso Yee

    1989-01-01

    Combination of suitable dimensioning and cladding of neodymium:yttrium aluminum garnet of similar solid-state laser provides for more efficient utilization of transversely-incident pump light from diode lasers. New design overcomes some of limitations of longitudinal- and older transverse-pumping concepts and promotes operation at higher output powers in TEM00 mode.

  7. Performance of a Centrifugal Slurry Pump

    Directory of Open Access Journals (Sweden)

    Hawas Yahya Bajawi

    2014-02-01

    Full Text Available The aim of this study was to experimentally investigate the effect of speed, concentration and size of slurry on the performance of a centrifugal pump. For this purpose a facility was built where the performance of a centrifugal slurry pump was examined using aggregate slurry. Three sizes of slurry with three concentrations and at three impeller speeds were used for the performance investigations of a centrifugal slurry pump. As a reference performance the performance of centrifugal slurry pump was also tested with clean water. The performance of pump has been reported as variations of head, power and efficiency at various flow rates along with the system characteristics of the pump. The results reveal that the pump performance is grossly affected by the type of slurry, its concentration and size. Besides this the variation in speed also affects the performance as is observed in pumps with water. The maximum decrease in the head, with respect to clear water, at the operating point was found to be 47% for aggregate for size 20 mm, 15% concentration and 2600 rpm. The maximum decrement in efficiency at operating point for aggregate was found to be 47% for 4 mm size, 15% concentration and at 2200 rpm. The power increment requirement for aggregate was 9% for 4 mm size, 15% concentration and 2600 rpm.

  8. 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.

  9. Nonlinear Aspects of Heat Pump Utilization

    Directory of Open Access Journals (Sweden)

    R. Najman

    2010-01-01

    Full Text Available This work attempts to answer the question: How much can we believe that the coefficient of performance provided by the manufacturer is correct, when a heat pump is required to face the real load coming from changes of temperature? The paper summarizes some basics of heat pump theory and describes the results of numerical models.

  10. Fluid structure interaction in piston diaphragm pumps

    NARCIS (Netherlands)

    Van Rijswick, R.; Van Rhee, C.

    2013-01-01

    Piston diaphragm pumps are used world-wide for the transport of aggressive and/or abrasive fluids in the chemical, mining and mineral processing industries. Figure 1 shows a cross section of a piston diaphragm pump as is used in the mining and mineral processing industries for the transport of miner

  11. ENERGY STAR Certified Geothermal Heat Pumps

    Science.gov (United States)

    Certified models meet all ENERGY STAR requirements as listed in the Version 3.0 ENERGY STAR Program Requirements for Geothermal Heat Pumps that are effective as of January 1, 2012. A detailed listing of key efficiency criteria are available at http://www.energystar.gov/index.cfm?c=geo_heat.pr_crit_geo_heat_pumps

  12. 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.

  13. [Interaction between clopidogrel and proton pump inhibitors

    NARCIS (Netherlands)

    Harmsze, A.M.; Boer, A. de; Boot, H.; Deneer, V.H.; Heringa, M.; Mol, P.G.; Schalekamp, T.; Verduijn, M.M.; Verheugt, F.W.A.; Comte, M. le

    2011-01-01

    The drug interaction between proton pump inhibitors and clopidogrel has been the subject of much study in recent years. Contradictory results regarding the effect of proton pump inhibitors on platelet reactivity and on clinical outcome in clopidogrel-treated patients have been reported in literature

  14. Lasers from fission. [nuclear pumping feasibility experiments

    Science.gov (United States)

    Schneider, R. T.; Thom, K.; Helmick, H. H.

    1975-01-01

    The feasibility of the nuclear pumping of lasers was demonstrated in three experiments conducted independently at three different laboratories. In this context nuclear pumping of lasers is understood to be the excitation of a laser by the kinetic energy of the fission fragments only. A description is given of research concerned with the use of nuclear energy for the excitation of gas lasers. Experimental work was supplemented by theoretical research. Attention is given to a nuclear pumped He-Xe laser, a nuclear pumped CO laser, and a neon-nitrogen laser pumped by alpha particles. Studies involving uranium hexafluoride admixture to laser media are discussed along with research on uranium hexafluoride-fueled reactors.

  15. Structure and operation of bacterial tripartite pumps.

    Science.gov (United States)

    Hinchliffe, Philip; Symmons, Martyn F; Hughes, Colin; Koronakis, Vassilis

    2013-01-01

    In bacteria such as Pseudomonas aeruginosa and Escherichia coli, tripartite membrane machineries, or pumps, determine the efflux of small noxious molecules, such as detergents, heavy metals, and antibiotics, and the export of large proteins including toxins. They are therefore influential in bacterial survival, particularly during infections caused by multidrug-resistant pathogens. In these tripartite pumps an inner membrane transporter, typically an ATPase or proton antiporter, binds and translocates export or efflux substrates. In cooperation with a periplasmic adaptor protein it recruits and opens a TolC family cell exit duct, which is anchored in the outer membrane and projects across the periplasmic space between inner and outer membranes. Assembled tripartite pumps thus span the entire bacterial cell envelope. We review the atomic structures of each of the three pump components and discuss how these have allowed high-resolution views of tripartite pump assembly, operation, and possible inhibition.

  16. Microfluidic Pumps Containing Teflon [Trademark] AF Diaphragms

    Science.gov (United States)

    Willis, Peter; White, Victor; Grunthaner, Frank; Ikeda, Mike; Mathies, Richard A.

    2009-01-01

    Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves. Other potential applications include implanted biomedical microfluidic devices, wherein the biocompatability of Teflon AF polymers would be highly advantageous. These pumps and valves have been demonstrated to function stably after cycling through temperatures from -125 to 120 C. These pumps and valves are intended to be successors to similar prior pumps and valves containing diaphragms made of polydimethylsiloxane (PDMS) [commonly known as silicone rubber]. The PDMS-containing valves ae designed to function stably only within the temperature range from 5 to 80 C. Undesirably, PDMS membranes are somwehat porous and retain water. PDMS is especially unsuitable for use at temperatures below 0 C because the formation of ice crystals increases porosity and introduces microshear.

  17. Unitary air-to-air heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J.E.

    1977-07-01

    This technology evaluation covers commercially available unitary heat pumps ranging from nominal capacities of 1/sup 1///sub 2/ to 45 tons. The nominal COP of the heat pump models, selected as representative, vary from 2.4 to 2.9. Seasonal COPs for heat pump installations and single-family dwellings are reported to vary from 2.5 to 1.1, depending on climate. For cooling performance, the nominal EER's vary from 6.5 to 8.7. Representative part-load performance curves along with cost estimating and reliability data are provided to aid: (1) the systems design engineer to select suitably sized heat pumps based on life-cycle cost analyses, and (2) the computer programmer to develop a simulation code for heat pumps operating in an Integrated Community Energy System.

  18. Hybrid pump for Pazflor deepwater development

    Energy Technology Data Exchange (ETDEWEB)

    Bibet, Pierre-Jean

    2010-07-01

    Subsea Processing gives engineers permanent technical challenges due to the comprehensive specifications which often stretch the proven limits of technology. It is particularly true for pumps that have to boost a multiphase effluent, because they must, often at the same time, be tolerant to free gas, able to handle very viscous, generate a high ?P, and be efficient. The Pazflor project decided to base the development on full utilization of subsea pumps. This paper presents the state of the art of the pumps that are designed to be installed on the sea floor. It further describes why existing technology could not match the technical requirements for the Pazflor project. It finally presents the pump specifically developed for this world first full field's development application, the so called 'Hybrid Pump', with the description of the associated qualification program and results. (Author)

  19. DNA detection by THz pumping

    Energy Technology Data Exchange (ETDEWEB)

    Chernev, A. L. [Russian Academy of Sciences, St. Petersburg Academic University—Nanotechnology Research and Education Centre (Russian Federation); Bagraev, N. T.; Klyachkin, L. E. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Emelyanov, A. K.; Dubina, M. V. [Russian Academy of Sciences, St. Petersburg Academic University—Nanotechnology Research and Education Centre (Russian Federation)

    2015-07-15

    DNA semiconductor detection and sequencing is considered to be the most promising approach for future discoveries in genome and proteome research which is dramatically dependent on the challenges faced by semiconductor nanotechnologies. DNA pH-sensing with ion-sensitive field effect transistor (ISFET) is well-known to be a successfully applied electronic platform for genetic research. However this method lacks fundamentally in chemical specificity. Here we develop the first ever silicon nanosandwich pump device, which provides both the excitation of DNA fragments’ self-resonant modes and the feedback for current-voltage measurements at room temperature. This device allows direct detection of singlestranded label-free oligonucleotides by measuring their THz frequency response in aqueous solution. These results provide a new insight into the nanobioelectronics for the future real-time technologies of direct gene observations.

  20. Haglund syndrome with pump bump.

    Science.gov (United States)

    Kucuksen, Sami; Karahan, Ali Yavuz; Erol, Kemal

    2012-01-01

    Haglund's syndrome, which is an inflammation of the bursa and a bony enlargement on the back of the heel that most often leads to painful bursitis, is a rare cause of retrocalcaneal pain. The clinical diagnosis is often confusing as the clinical picture may mimic other causes of hindfoot pain such as isolated retrocalcaneal bursitis or hindfoot involvement from more systemic disorders such as seronegative spondyloarthropathies (Reiter's syndrome, ankylosing spondylitis) or rheumatoid arthritis. This report is of a 60-year-old woman with a painful swelling of the right heel, who was diagnosed with Haglund syndrome. The characteristic clinical photograph (showing the prominent 'pump bump'), radiographical and magnetic resonance imaging features are presented.

  1. GEOTHERMAL HEAT PUMP GROUTING MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    ALLAN,M.

    1998-04-01

    The thermal conductivity of cementitious grouts has been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. The cement-sand grouts were also tested for rheological characteristics, bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the thermal conductivity, permeability, bonding and exotherm data for selected cementitious grouts. The theoretical reduction in bore length that could be achieved with the BNL-developed cement-sand grouts is examined. Finally, the FY 98 research and field trials are discussed.

  2. Geothermal heat pump grouting materials

    Energy Technology Data Exchange (ETDEWEB)

    Allan, M.

    1998-08-01

    The thermal conductivity of cementitious grouts has been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. The cement-sand grouts were also tested for rheological characteristics, bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the thermal conductivity, permeability, bonding and exotherm data for selected cementitious grouts. The theoretical reduction in bore length that could be achieved with the BNL-developed cement-sand grouts is examined. Finally, the FY 98 research and field trials are discussed.

  3. Optimum pump armament in supply networks; Optimal pumpebestykning i forsynignssystemer

    Energy Technology Data Exchange (ETDEWEB)

    Kristjansson, Halldor

    2005-06-15

    The report presents recommendations as regards pump armament in district heating pump centres and the linked savings. A model has been built which shows variations of efficiency for motor and pump. (BA)

  4. 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.

  5. Off-Pump Versus On-Pump Coronary Artery Bypass Grafting

    DEFF Research Database (Denmark)

    Møller, Christian H; Steinbrüchel, Daniel A

    2014-01-01

    Coronary artery bypass grafting (CABG) remains the preferred treatment in patients with complex coronary artery disease. However, whether the procedure should be performed with or without the use of cardiopulmonary bypass, referred to as off-pump and on-pump CABG, is still up for debate....... Intuitively, avoidance of cardiopulmonary bypass seems beneficial as the systemic inflammatory response from extracorporeal circulation is omitted, but no single randomized trial has been able to prove off-pump CABG superior to on-pump CABG as regards the hard outcomes death, stroke or myocardial infarction....... In contrast, off-pump CABG is technically more challenging and may be associated with increased risk of incomplete revascularization. The purpose of the review is to summarize the current literature comparing outcomes of off-pump versus on-pump coronary artery bypass surgery....

  6. Prediction of potential failures in hydraulic gear pumps

    OpenAIRE

    E. Lisowski(Cracow Tech. U); J. Fabiś

    2010-01-01

    Hydraulic gear pumps are used in many machines and devices. In hydraulic systems of machines gear pumps are main component ofsupply unit or perform auxiliary function. Gear pumps opposite to vane pumps are less complicated. They consists of such components as:housing, gear wheels, bearings, shaft, seal for rotation motion which are not very sensitive for damage and that is why they are using veryoften. However, gear pumps are break down from time to time. Usually damage of pump cause shutting...

  7. Research on mechanical compression heat pump applying to petroleum and chemical enterprise%机械压缩式热泵在石化企业的应用研究

    Institute of Scientific and Technical Information of China (English)

    韩莉; 司继林; 项曙光

    2013-01-01

    Mechanical compression heat pump was simulated by a chemical process simulation software-Aspen Plus, and the temperature rise, superheating and supercooling degree, selection of working medium and the application of multistage pump were studied.The research results show that, the maximum temperature of single stage compression heat pump is 45 ℃. The optimal degree of superheat is 5 ℃. the optimum working fluid is R152a when the condensing temperature arranges from 60 ℃ to 80 ℃, while the comprehensive properties of R143 or R123 is the best when the temperature range is from 80 to 110 or 110 to 160, respectively. The comprehensive performance of cascade heat pump is better than other forms of multistage pump. The maximum temperature rise of multistage pump is limited by working fluids. Currently, the maximum temperature rise is up to 115 ℃.%应用化工流程模拟软件Aspen Plus对机械压缩式热泵进行模拟,并且对机械压缩式热泵温升、过热和过冷度、工质选取以及多级热泵的应用进行研究。研究结果表明:单级压缩式热泵的最大温升为45℃;最佳过热度为2℃,最佳过冷度为5℃;冷凝温度在60℃~80℃范围内最佳工质为R152 a,在80℃~110℃温度区间内R143综合性能最优,在110℃~160℃温度区间内 R123最优;复叠式热泵综合性能优于其它形式多级热泵;多级热泵的最大温升受工质的限制,在目前的工质范围内,最大温升可达115℃。

  8. Management of the hospitalized diabetes patient with an insulin pump.

    Science.gov (United States)

    McCrea, Deborah

    2013-03-01

    More than 375,000 Americans manage their diabetes with an insulin pump, and this number continues to increase. Many of these patients will want to remain on their insulin pump while hospitalized, so the nurse needs to know about how to care for the hospitalized patient wearing an insulin pump. This article discusses the benefits of intensive insulin therapy, how the insulin pump works, initial insulin-pump dosing, candidate selection, advantages and disadvantages of using an insulin pump, troubleshooting the pump, nursing care of the hospitalized patient wearing an insulin pump, and development of hospital protocols for the care of such patients. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Jet pump noise analysis for BWRs

    Energy Technology Data Exchange (ETDEWEB)

    Castillo-Duran, R.; Hernandez-lopez, H.; Ortiz-Villafuerte, J.; Alonso-Vargas, G. [Instituto Nacional de Investigaciones Nucleares, Mexico (Mexico); Calleros-Micheland, G. [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Veracruz (Mexico)

    2004-07-01

    The use of noise analysis for detection of BWR component malfunction is a powerful tool in determining abnormal operation conditions, during the life of a nuclear power plant. Since the eighties, several nuclear reactors have reported problems related with jet pumps and recirculation loops. The NRC (Nuclear Regulatory Commission) recommends performing periodic monitoring to individual pressure drop jet pumps, to prevent structural failure. In this work, noise analysis methods are used for detection of jet pumps abnormal operation conditions in a BWR. Power signals obtained from the backup process computer of a BWR are analyzed with a home-developed software, called NOISE, for noise diagnostic of power signals. The computer program takes individual signals from the tabular report of the process computer. The normalized power spectral density (NPSD) is then obtained, using a Prime Factor Algorithm to calculate the Fast Fourier Transform. The NPSD of the jet pumps pressure drop, of Unit 2 of the Laguna Verde Nuclear Power Plant, showed a noticeable change in jet pump 6 during 2003, considering the period from the startup test to operation during 2003. This abnormal condition was due to that the jet pump throat was partially blocked. The noise analysis methodology is shown to be a useful tool for malfunction detection, and could be applied to create a data bank for monitoring the dynamic behavior of BWR jet pumps. (authors)

  10. Advanced heat pump research and development

    Science.gov (United States)

    Kuliasha, M. A.

    The Office of Building Energy Research and Development of the U.S. Department of Energy (DOE), has been funding R&D in advanced heat pumps and appliances since 1976. Much of that research has been managed for DOE by the Oak Ridge National Laboratory (ORNL). The objective of the Building Equipment Research (BER) program at ORNL has been to generate new concepts and develop a technology base for improving the energy efficiency and load characteristics of energy conversion equipment used in residential and commercial buildings. The research being pursued to achieve these objectives falls under three general areas: thermally activated heat pumps (TAHP), refrigeration systems, and building equipment systems. The TAHP work is concentrated on three technologies: (1) absorption heat pumps; (2) Stirling engine-driven heat pumps; and (3) internal combustion (IC) engine-driven heat pumps. Major project areas in refrigeration systems research include electric heat pumps, ground-coupled heat pumps, and refigerant mixtures. In the building equipment systems areas, project areas include advanced distribution systems, advanced insulation for appliances, and commercial building equipment.

  11. Monitoring DNAPL pumping using integrated geophysical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Newmark, R.L.

    1997-01-01

    The removal of DNAPL during pumping was monitored. At Hill AFB in Utah, a free-product DNAPL plume (predominantly TCE, with some TCA, PCE, methylene chloride) is pooled in water-wet soil on a thick clay aquitard. Groundwater pumping at Operable Unit 2 began in 1994; to date, nearly 30,000 gal DNAPL have been recovered. From Sept. 1994 through Sept. 1995, changes in the basin during DNAPL pumping were monitored using fiber optic chemical sensors, neutron logs, and electrical resistance tomography (ERT). The first two sensor types verify the presence of DNAPL in vicinity of 3 boreholes which form a cross section from the perimeter of the basin to its center. Cross borehole ERT images the changes in formation electrical properties due to removal of DNAPL, extending the understanding of DNAPL removal between the boreholes. During pumping, electrical resistivities decreased; we suggest these decreases are directly caused by the reduction in DNAPL. During ground water pumping, water with relatively low resistivity replaces some of the DNAPL pockets as the highly insulating DNAPL is removed. Results suggest that, as DNAPL is pumped from a nearby well, product slowly drains along the top of an aquitard and into the pump well, where it collects.

  12. Clinical experience with the Sarns centrifugal pump.

    Science.gov (United States)

    Curtis, J J; Walls, J T; Demmy, T L; Boley, T M; Schmaltz, R A; Goss, C F; Wagner-Mann, C C

    1993-07-01

    Since October 1986, we have had experience with 96 Sarns centrifugal pumps in 72 patients (pts). Heparinless left atrial to femoral artery or aorta bypass was used in 14 pts undergoing surgery on the thoracic aorta with 13 survivors (93%). No paraplegia or device-related complications were observed. In 57 patients, the Sarns centrifugal pump was used as a univentricular (27 pts) or biventricular (30 pts) cardiac assist device for postcardiotomy cardiogenic shock. In these patients, cardiac assist duration ranged from 2 to 434 h with a hospital survival rate of 29% in those requiring left ventricular assist and 13% in those requiring biventricular assist. Although complications were ubiquitous in this mortally ill patient population, in 5,235 pump-hours, no pump thrombosis was observed. Hospital survivors followed for 4 months to 6 years have enjoyed an improved functional class. We conclude that the Sarns centrifugal pump is an effective cardiac assist device when used to salvage patients otherwise unweanable from cardiopulmonary bypass. Partial left ventricular bypass using a centrifugal pump has become our procedure of choice for unloading the left ventricle and for maintenance of distal aortic perfusion pressure when performing surgery on the thoracic aorta. This clinical experience with the Sarns centrifugal pump appears to be similar to that reported with other centrifugal assist devices.

  13. 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.

  14. Pulsed pumping of semiconductor disk lasers.

    Science.gov (United States)

    Hempler, Nils; Hopkins, John-Mark; Kemp, Alan J; Schulz, Nico; Rattunde, Marcel; Wagner, Joachim; Dawson, Martin D; Burns, David

    2007-03-19

    Efficient operation of semiconductor disk lasers is demonstrated using uncooled and inexpensive 905nm high-power pulsed semiconductor pump lasers. Laser emission, with a peak power of 1.7W, is obtained from a 2.3mum semiconductor disk laser. This is seven times the power achieved under continuous pumping. Analysis of the time-dependent spectral characteristics of the laser demonstrate that significant device heating occurs over the 100-200ns duration of the pumping pulse - finite element modelling of the thermal processes is undertaken in support of these data. Spectral narrowing to below 0.8nm is obtained by using an intra-cavity birefringent filter.

  15. Vibration of safety injection pump motors

    Energy Technology Data Exchange (ETDEWEB)

    Wattrelos, D.

    1996-12-01

    This paper covers a fault encountered in the safety injection pump motors of the French 900 MWe unit nuclear power stations. This fault was not revealed either during the low pressure safety injection and containment spray system pump qualification tests under accident conditions or during the special tests on a test bench carried out to attempt to replicate the fault and to identify ways of remedying it. This constitutes a potential common mode of failure of the safety injection system and the containment spray system pumps. The vibration phenomena illustrate the importance of carrying out tests in the plants under conditions as close as possible to those of actual accident situations.

  16. Heat pumps in agricultural uses. Factsheet

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, R.D.

    1986-04-01

    This paper provides an elementary introduction to heat pumps and their potential for use in Ontario agricultural applications, taking into account local climatic conditions which mean high heating loads and small cooling loads. A heat pump's ability to remove heat from a variety of sources and boost this heat to a useable temperature enables such farm uses as recovery of heat from exhaust air in livestock barns, greenhouse heating using ground water, and heat extraction from manure. Basic types of heat pumps are evaluated and compared, and their costs are estimated.

  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. Unitary water-to-air heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J.E.

    1977-10-01

    Performance and cost functions for nine unitary water-to-air heat pumps ranging in nominal size from /sup 1///sub 2/ to 26 tons are presented in mathematical form for easy use in heat pump computer simulations. COPs at nominal water source temperature of 60/sup 0/F range from 2.5 to 3.4 during the heating cycle; during the cooling cycle EERs range from 8.33 to 9.09 with 85/sup 0/F entering water source temperatures. The COP and EER values do not include water source pumping power or any energy requirements associated with a central heat source and heat rejection equipment.

  19. 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.

  20. Polarization chaos in an optically pumped laser.

    Science.gov (United States)

    Serrat, C; Kul'minskii, A; Vilaseca, R; Corbalán, R

    1995-06-15

    We study the steady-state and dynamic behavior of an optically pumped J = 0 ? J = 1 ? J = 0 laser operating with an isotropic ring cavity and an axial magnetic field. The gain anisotropy induced by a linearly polarized pump-laser f ield leads, in the steady state, to locking of the two circularly polarized components of the laser field, which acquires a linear polarization parallel to that of the pump field. In the presence of laser intensity instabilities, however, locking does not occur, and polarization instabilities appear. For the f irst time to our knowledge, polarization chaos has been found in a laser system.

  1. Self-Pumping Active Gel

    Science.gov (United States)

    Wu, Kun-Ta; Hishamunda, Jean Bernard; Fraden, Seth; Dogic, Zvonimir

    Isotropic active gels are the network which is consist of cross-linked building blocks and the structure of which changes randomly and isotropically with time. Dogic et. al. show that pairs of anti-parallel microtubules form extensile bundles, which merge, extend, and buckle. In an unconfined system, the dynamics of these bundles causes spontaneous turbulent-like flow driven by motion of microscopic molecular motors. We found that confining these active gels in a millimeter sized toroids causes a transition into a new dynamical state characterized by circulation currents persisting for hours until ATP is depleted. We show how toroid dimensions impact the properties of self-organized circular currents, how directions of circulation can be designed by engineering ratchet-shaped boundaries, and how circulations of connected toroids can be either synchronized or antisynchronized. Furthermore, we demonstrate that the flow rate in the circulation is independent of curvature and length of flow path. The flow rate persists for centimeters without decay, disregarding conventional pipe flow resistance. Such findings pave the path to self-pumping pipe transport and performing physical work with biological system.

  2. Offshore watersource heat pump applications

    Energy Technology Data Exchange (ETDEWEB)

    Clark, W.H. II [ARK Associates, Round Rock, TX (United States)

    1996-10-01

    This paper discusses applications of the Water Source Heat Pump (WSHP) technology for offshore drilling or production operations to result in a substantial savings in space conditioning to result in a substantial savings in space conditioning and domestic hot water production. An even more cost competitive application of the WSHP is the once thorough design which circulates cool water from deep in the ocean straight through the unit, then discharges it to the ocean surface. A modification of this open loop technique circulates the fluid within an abandoned well bore casing. The advantage of this system is that natural convection of warm water from deep in the well upward, as the unit returns cool water at or near the surface, will greatly enhance the thermal advantage of the system. This will enable direct use in the heating season and perhaps be sufficient to operate an absorption chiller in the cooling season. The initial cost of either of these systems is equivalent to a packaged ac system, making the WSHP an ideal energy conservation measure.

  3. Staged regenerative sorption heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1995-01-01

    A regenerative adsorbent heat pump process and system for cooling and heating a space. A sorbent is confined in a plurality of compressors of which at least four are first stage and at least four are second stage. The first stage operates over a first pressure region and the second stage over a second pressure region which is higher than the first. Sorbate from the first stage enters the second stage. The sorbate loop includes a condenser, expansion valve, evaporator and the compressors. A single sorbate loop can be employed for single-temperature-control such as air conditioning and heating. Two sorbate loops can be used for two-temperature-control as in a refrigerator and freezer. The evaporator temperatures control the freezer and refrigerator temperatures. Alternatively the refrigerator temperature can be cooled by the freezer with one sorbate loop. A heat transfer fluid is circulated in a closed loop which includes a radiator and the compressors. Low temperature heat is exhausted by the radiator. High temperature heat is added to the heat transfer fluid entering the compressors which are desorbing vapor. Heat is transferred from compressors which are sorbing vapor to the heat transfer fluid, and from the heat transfer fluid to the compressors which are desorbing vapor. Each compressor is subjected to the following phases, heating to its highest temperature, cooling down from its highest temperature, cooling to its lowest temperature, and warming up from its lowest temperature. The phases are repeated to complete a cycle and regenerate heat.

  4. Liquid-metal pumps for large-scale breeder-reactor plant (prototype pump)

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, M. (comp.)

    1976-07-01

    This report presents the recommended pump design for use in Large Scale Liquid Metal Fast Breeder Reactor plants. The base design for the pump will circulate 127,000 GPM of liquid sodium at temperatures up to 850/sup 0/F and with a total discharge head at the design point of 500 feet Na with an impeller that is 40 feet below the sodium seal. The pump design is predicated on developing an impeller design which will have a suction specific speed (S/sub n/) of about 20,000 with 20 feet NPSH available, which will result in a pump speed of 530 RPM at design conditions. The design is based on the technology developed in the design and fabrication of FFTF pumps, the design efforts for the Clinch River Breeder Reactor Pump design study and other technology.

  5. Impact of the lubricating oil on thermodynamic performances of reversible heat pumps; Impact de l'huile de lubrification sur les performances thermodynamiques des pompes a chaleur reversibles

    Energy Technology Data Exchange (ETDEWEB)

    Youbi-Idrissi, M.

    2003-12-01

    This work deals with the effect of oil on the energy performances of refrigerating systems. To characterise this impact, two thermodynamic properties were studied: the solubility and the enthalpy. Thus, a simple measurement method was presented, allowing to study both transient and steady-state behaviour of various refrigerant/oil pairs. Thus, experimental data were validated and modelled. The suitable use of the solubility curves showed the zeotropic character of the refrigerant/oil mixture, which is directly reflected on the enthalpy calculation. For this property, a thermodynamic model was developed and experimentally validated. Its application led to a new presentation of the Mollier diagram taking into account the oil presence. It was then shown that, among all the circuit elements, the evaporator is the most penalized by the oil presence. Its performances decrease when the circulating mass fraction of oil increases, the superheat decreases and when the refrigerant-oil solubility increases. An experimental study on a reversible heat pump confirmed that if the circulation mass fraction of oil in the machine is lower than 2%, the impact of oil is reduced. Lastly, a local model of a refrigerating unit, initially charged with a zeotropic mixture, allowed to analyse the profiles of temperature, heat transfer coefficient and local composition of the refrigerant along a circuit. (author)

  6. ENERGY STAR Certified Geothermal Heat Pumps

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 3.0 ENERGY STAR Program Requirements for Geothermal Heat Pumps that are effective as of...

  7. Fault Detection and Isolation in Centrifugal Pumps

    DEFF Research Database (Denmark)

    Kallesøe, Carsten

    Centrifugal pumps are used in a variety of different applications, such as water supply, wastewater, and different industrial applications. Some pump installations are crucial for the applications to work. Failures can lead to substantial economic losses and can influence the life of many people...... when they occur. Therefore, detection of faults, if possible in an early stage, and isolation of their causes are of great interest. Especially fault detection, which can be used for predictive maintenance, can decrease working expenses and increase the reliability of the application in which the pump...... is placed. The topic of this work is Fault Detection and Identification in centrifugal pumps. Different approaches are developed with special focus on robustness. Robustness with respect to disturbances, unknown parts of the system, and parameter variations are considered. All developed algorithms...

  8. Strategies for discontinuation of proton pump inhibitors

    DEFF Research Database (Denmark)

    Haastrup, Peter; Paulsen, Maja S; Begtrup, Luise M

    2014-01-01

    PURPOSE: Proton pump inhibitors (PPIs) are considered to be overprescribed. Consensus on how to attempt discontinuation is, however, lacking. We therefore conducted a systematic review of clinical studies on discontinuation of PPIs. METHODS: Systematic review based on clinical studies investigating...

  9. High performance heat pump absorption cycles

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Longo, G.; Rossetto, L.

    1988-10-01

    Absorption heat pumps can provide high performances when operating in suitable cycles with multiple effects. This report describes some multistage cycles and evaluates the coefficient of performance realistically obtainable both in winter and summer working conditions.

  10. Performance of a New Lightweight Reciprocating Pump

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2005-06-09

    A new four-chamber piston pump design has been fabricated and tested. The small-scale propellant pump is intended to be powered by gas at elevated temperatures, e.g. in a gas-generator cycle rocket propulsion system. Two key features are combined for the first time: leak-tight liquid-cooled seals, and a high throughput per unit hardware mass. Measured performance curves quantify flows, pressures, leakage, volumetric efficiency, and tank pressure requirements. A pair of 300-gram pumps operating with significant margin could deliver fuel and oxidizer at 5 MPa to a compact lightweight 1000-N engine, while tank pressure remains at 0.35 MPa. Pump weight is well below one percent of thrust, as is typical for launch vehicle engines. Applications include small upper stages, aggressive maneuvers in space, and miniature launch vehicles for Mars ascent.

  11. Stronger Muscles May Pump Up Your Memory

    Science.gov (United States)

    ... 161647.html Stronger Muscles May Pump Up Your Memory Seniors saw lasting changes from weight-lifting twice ... may boost brain function in people with mild memory and thinking problems, a new study finds. The ...

  12. Diode-pumped optical parametric oscillator.

    Science.gov (United States)

    Geiger, A R; Hemmati, H; Farr, W H; Prasad, N S

    1996-02-01

    Diode-pumped optical parametric oscillation has been demonstrated for the first time to our knowledge in a single Nd:MgO:LiNbO(3) nonlinear crystal. The crystal is pumped by a semiconductor diode laser array at 812 nm. The Nd(3+) ions absorb the 812-nm radiation to generate 1084-nm laser oscillation. On internal Q switching the 1084-nm radiation pumps the LiNbO(3) host crystal that is angle cut at 46.5 degrees and generates optical parametric oscillation. The oscillation threshold that is due to the 1084-nm laser pump with a pulse length of 80 ns in a 1-mm-diameter beam was measured to be approximately 1 mJ and produced 0.5-mJ output at 3400-nm signal wavelength.

  13. Head pulsations in a centrifugal pump

    Science.gov (United States)

    Boiko, V. S.; Sotnyk, M. I.; Moskalenko, V. V.

    2017-08-01

    This article investigated the factors, which affect to the character of the head pulsations of a centrifugal pump. We investigated the dependence of the shape and depth of these pulsations from the operation mode of the pump. Was determined, that the head pulsations at the outlet of the impeller (pulsations on the blade passing frequency) cause head pulsations at the outlet of the pump, that have the same frequency, but differ in shape and depth. These pulsations depend on the design features of the flow-through part of the pump (from the ratio of hydraulic losses on the friction and losses on the vortex formation). A feature of the researches that were conducted is also the using of not only hydraulic but also electric modeling methods. It allows determining the values of the components of hydraulic losses.

  14. [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.

  15. Hot Topics! Heat Pumps and Geothermal Energy

    Science.gov (United States)

    Roman, Harry T.

    2009-01-01

    The recent rapid rises in the cost of energy has significantly increased interest in alternative energy sources. The author discusses the underlying principles of heat pumps and geothermal energy. Related activities for technology education students are included.

  16. Heat pumps in district heating networks

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    constraints limit the power plants. Efficient heat pumps can be used to decouple the constraints of electricity and heat production, while maintaining the high energy efficiency needed to match the politically agreed carbon emission goals. The requirements in terms of COP, location, capacity and economy...... are calculated using an energy system model which includes power plants, heat pumps and district heating consumption profiles. The model is developed with focus on accurate representation of the performance of the units in different locations and operating modes. The model can assist in investment decisions...... and strategic planning in the energy sector. The paper presents a case study of optimal implementation of heat pumps in the present energy system of the Copenhagen area. By introduction of the correct capacity of heat pumps, a 1,6 % reduction in fuel consumption for electricity and heat production can...

  17. Diamagnetic pumping in a rotating convection zone

    Science.gov (United States)

    Kitchatinov, L. L.; Nepomnyashchikh, A. A.

    2016-10-01

    Solar dynamo models require some mechanism for magnetic field concentration near the base of the convection zone in order to generate super-kilogauss toroidal fields with sufficiently large (∼ 1024 Mx) magnetic flux. We consider the downward diamagnetic pumping near the base of the convection zone as a possible concentration mechanism and derive the pumping velocities with allowance for the effect of rotation. Transport velocities for poloidal and toroidal fields differ in rotating fluid. The toroidal field is transported downward along the radius only but the pumping velocity for the poloidal field has an equatorward meridional component also. Previous results for cases of slow and rapid rotation are reproduced and the diamagnetic pumping expressions adapted for use in dynamo models are presented.

  18. Diamagnetic pumping in a rotating convection zone

    CERN Document Server

    Kitchatinov, L

    2016-01-01

    Solar dynamo models require some mechanism for magnetic field concentration near the base of the convection zone in order to generate super-kilogauss toroidal fields with sufficiently large (~10^{24} Mx) magnetic flux. We consider the downward diamagnetic pumping near the base of the convection zone as a possible concentration mechanism and derive the pumping velocities with allowance for the effect of rotation. Transport velocities for poloidal and toroidal fields differ in rotating fluid. The toroidal field is transported downward along the radius only but the pumping velocity for the poloidal field has an equatorward meridional component also. Previous results for cases of slow and rapid rotation are reproduced and the diamagnetic pumping expressions adapted for use in dynamo models are presented.

  19. Jet pump assisted arterial heat pipe

    Science.gov (United States)

    Bienert, W. B.; Ducao, A. S.; Trimmer, D. S.

    1978-01-01

    This paper discusses the concept of an arterial heat pipe with a capillary driven jet pump. The jet pump generates a suction which pumps vapor and noncondensible gas from the artery. The suction also forces liquid into the artery and maintains it in a primed condition. A theoretical model was developed which predicts the existence of two stable ranges. Up to a certain tilt the artery will prime by itself once a heat load is applied to the heat pipe. At higher tilts, the jet pump can maintain the artery in a primed condition but self-priming is not possible. A prototype heat pipe was tested which self-primed up to a tilt of 1.9 cm, with a heat load of 500 watts. The heat pipe continued to prime reliably when operated as a VCHP, i.e., after a large amount of noncondensible gas was introduced.

  20. Hot Topics! Heat Pumps and Geothermal Energy

    Science.gov (United States)

    Roman, Harry T.

    2009-01-01

    The recent rapid rises in the cost of energy has significantly increased interest in alternative energy sources. The author discusses the underlying principles of heat pumps and geothermal energy. Related activities for technology education students are included.

  1. Insulin pumps: Beyond basal-bolus

    National Research Council Canada - National Science Library

    Millstein, Richard; Becerra, Nancy Mora; Shubrook, Jay H

    2015-01-01

    Insulin pumps are a major advance in diabetes management, making insulin dosing easier and more accurate and providing great flexibility, safety, and efficacy for people who need basal-bolus insulin therapy...

  2. Technologies and Innovations for Hydraulic Pumps

    OpenAIRE

    Ivantysynova, Monika

    2016-01-01

    Positive displacement machines working as hydraulic pumps or hydraulic motors have always been, are and will be an essential part of any hydraulic system. Current trends and future demands on energy efficient systems will not only drastically increase the number of positive displacement machines needed for modern efficient hydraulic circuits but will significantly change the performance requirements of pumps and motors. Throttleless system configurations will change the landscape of hydraulic...

  3. Electrically Pumped Vertical-Cavity Amplifiers

    DEFF Research Database (Denmark)

    Greibe, Tine

    2007-01-01

    In this work, the design of electrically pumped vertical cavity semiconductor optical amplifiers (eVCAs) for use in a mode-locked external-cavity laser has been developed, investigated and analysed. Four different eVCAs, one top-emitting and three bottom emitting structures, have been designed...... and discussed. The thesis concludes with recommendations for further work towards the realisation of compact electrically pumped mode-locked vertical externalcavity surface emitting lasers....

  4. Commercial absorption heat pumps (design, performance)

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R. (Padua Univ. (Italy). Ist. di Fisica Tecnica)

    1986-04-01

    After a historical review of the development of absorption heat pumps, a critical analysis is presented of the design and operation of typical 25-40 kW, commercially available heat pumps. This engineering critique is followed by an analysis of the performance of 25 kW plant thoroughly tested to provide, by means of statistically significant data, a reliable assessment of the coefficient of performance and capacity in function of the cold source temperature for different return temperatures.

  5. Intracavity interferometry using synchronously pumped OPO

    Science.gov (United States)

    Zavadilová, Alena; Vyhlídal, David; Kubeček, Václav; Šulc, Jan; Navrátil, Petr

    2016-12-01

    The concept of system for intracavity interferometry based on the beat note detection in subharmonic synchronously intracavity pumped optical parametrical oscillator (OPO) is presented. The system consisted of SESAM-modelocked, picosecond, diode pumped Nd:YVO4 laser, operating at wavelength 1.06 μm and tunable linear intracavity pumped OPO based on MgO:PPLN crystal, widely tunable in 1.5 μm able to deliver two independent trains of picosecond pulses. The optical length of the OPO cavity was set to be exactly twice the pumping cavity length. In this configuration the OPO produces signal pulses with the same repetition frequency as the pump laser but the signal consists of two completely independent pulse trains. For purpose of pump probe measurements the setup signal with half repetition rate and scalable amplitude was derived from the OPO signal using RF signal divider, electropotical modulator and fiber amplifier. The impact of one pump beam on the sample is detected by one probing OPO train, the other OPO train is used as a reference. The beat note measured using the intracavity interferometer is proportional to phase modulation caused by the pump beam. The bandwidth of observed beat-note was less than 1 Hz (FWHM), it corresponds to a phase shift measurement error of less than 1.5 × 10-7 rad without any active stabilization. Such compact low-cost system could be used for ultra-sensitive phase-difference measurements (e.g. nonlinear refractive index measurement) for wide range of material especially in spectral range important for telecom applications.

  6. Economics of heat pump assisted drying systems

    Energy Technology Data Exchange (ETDEWEB)

    Pendyala, V.R.; Devotta, S.; Patwardhan, V.S.

    1986-01-01

    The sensitivity of the economics of heat pump assisted dryers to various factors such as design, operational and economic variables, when payback period is adopted as the criterion, has been assessed for Indian conditions. Results have been presented in graphical form to illustrate the optimum conditions for economic viability. For the specific typical conditions and the current costs of electricity and steam in India, a heat pump assisted dryer has a payback period in the range of two to three years.

  7. Functional studies of sodium pump isoforms

    DEFF Research Database (Denmark)

    Clausen, Michael Jakob

    The Na+,K+-ATPase is an essential ion pump found in all animal cells. It uses the energy from ATP hydrolysis to export three Na+ and import two K+, both against their chemical gradients and for Na+ also against the electrical potential. Mammals require four Na+,K+-ATPase isoforms that each have u...... synthesized cohorts of pumps from the Golgi apparatus to the plasma membrane....

  8. Mini drug pump for ophthalmic use.

    Science.gov (United States)

    Saati, Saloomeh; Lo, Ronalee; Li, Po-Ying; Meng, Ellis; Varma, Rohit; Humayun, Mark S

    2010-03-01

    To evaluate the feasibility of developing a novel mini drug pump for ophthalmic use. Using principles of microelectromechanical systems engineering, a mini drug pump was fabricated. The pumping mechanism is based on electrolysis and the pump includes a drug refill port as well as a check valve to control drug delivery. Drug pumps were tested first on the bench-top and then after implantation in rabbits. For the latter, we implanted 4 elliptical (9.9 x 7.7 x 1.8 mm) non-electrically active pumps into 4 rabbits. The procedure is similar to implantation of a glaucoma aqueous drainage device. To determine the ability to refill and also the patency of the cannula, at intervals of 4-6 weeks after implantation, we accessed the drug reservoir with a transconjunctival needle and delivered approximately as low as 1 microL of trypan blue solution (0.06%) into the anterior chamber. Animals were followed by slit lamp examination, photography, and fluorescein angiography. Bench-top testing showed 2.0 microL/min delivery when using 0.4 mW of power for electrolysis. One-way valves showed reliable opening pressures of 470 mmHg. All implanted devices refilled at 4-6 weeks intervals for 4-6 months. No infection was seen. No devices extruded. No filtering bleb formed over the implant. A prototype ocular mini drug pump was built, implanted, and refilled. Such a platform needs more testing to determine the long term biocompatibility of an electrically-controlled implanted pump. Testing with various pharmacological agents is needed to determine its ultimate potential for ophthalmic use.

  9. Laser-induced quantum pumping in graphene

    Energy Technology Data Exchange (ETDEWEB)

    San-Jose, Pablo [Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123, 28006 Madrid (Spain); Prada, Elsa; Kohler, Sigmund [Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid (Spain); Schomerus, Henning [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom)

    2012-10-08

    We investigate non-adiabatic electron pumping in graphene generated by laser irradiation with linear polarization parallel or perpendicular to the transport direction. Transport is dominated by the spatially asymmetric excitation of electrons from evanescent into propagating modes. For a laser with parallel polarization, the pumping response exhibits a subharmonic resonant enhancement which directly probes the Fermi energy; no such enhancement occurs for perpendicular polarization. The resonance mechanism relies on the chirality of charge carriers in graphene.

  10. Small, submersible, centrifugal pump for liquid nitrogen

    DEFF Research Database (Denmark)

    Rustad, B.M.; Nielsen, A.; Passell, L.

    1965-01-01

    Full details are given of a pump designed to circulate several liters/min. It can be evacuated before use to exclude oxygen and may be used at pressures of several atmospheres.......Full details are given of a pump designed to circulate several liters/min. It can be evacuated before use to exclude oxygen and may be used at pressures of several atmospheres....

  11. A Depolarizing Electrogenic Pump in Frog Muscle

    Science.gov (United States)

    1975-08-01

    mw copy AFRRI SR75-20 AUGUST 1975 AFRRI SCIENTIFIC REPORT O ■ to A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. Geduldig D. R...Academy of Sciences - National Research Council. AFRRI SR75-20 August 1975 A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. GEDULDIG* D. R...INTRODUCTION When Na-enriched frog muscles are bathed in Na- and K-free saline, the small amount of potassium which could accumulate outside of the membrane

  12. S-102 Transfer Pump Restriction Modeling Results

    Energy Technology Data Exchange (ETDEWEB)

    Wells, Beric E.; Johnson, Kenneth I.; Rector, David R.; Trent, Donald S.

    2008-03-27

    It was determined that a radioactive waste leak in the Hanford S Farm in the vicinity of the S-102 retrieval pump discharge occurred because of over-pressurization and failure of the S-102 dilution water supply hose while operating the retrieval pump in reverse with an obstructed suction cavity and an unobstructed flow path to the dilution water supply hose. This report describes efforts to identify plausible scenarios for the waste leak to occur.

  13. Ho:YLF pumped HBr laser

    CSIR Research Space (South Africa)

    Botha, LR

    2009-10-01

    Full Text Available . The model included rotational thermalization within a specific vibrational band as well as vibrational relaxation of both the upper and lower vibrational levels partaking in the laser action. The model is similar to that reported in [2] and [7]. The pump.... The efficiency of converting the 2 micron pump energy to 4 micron output energy is primarily controlled by the rotational and vibrational relaxation times. As the pressure of the laser medium is increased, the rotational and vibrational relaxation times...

  14. A teaspoon pump for pumping blood with high hydraulic efficiency and low hemolysis potential.

    Science.gov (United States)

    Dame, D

    1996-06-01

    Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.

  15. Performance Analysis Of Single-Pumped And Dual-Pumped Parametric Optical Amplifier

    Directory of Open Access Journals (Sweden)

    Sandar Myint

    2015-06-01

    Full Text Available Abstract In this study we present a performance analysis of single-pumped and dual- pumped parametric optical amplifier and present the analysis of gain flatness in dual- pumped Fiber Optical Parametric Amplifier FOPA based on four-wave mixing FWM. Result shows that changing the signal power and pump power give the various gains in FOPA. It is also found out that the parametric gain increase with increase in pump power and decrease in signal power. .Moreover in this paper the phase matching condition in FWM plays a vital role in predicting the gain profile of the FOPAbecause the parametric gain is maximum when the total phase mismatch is zero.In this paper single-pumped parametric amplification over a 50nm gain bandwidth is demonstrated using 500 nm highly nonlinear fiber HNLF and signal achieves about 31dB gain. For dual-pumped parametric amplification signal achieves 26.5dB gains over a 50nm gain bandwidth. Therefore dual-pumped parametric amplifier can provide relatively flat gain over a much wider bandwidth than the single-pumped FOPA.

  16. Classification of physiologically significant pumping states in an implantable rotary blood pump: patient trial results.

    Science.gov (United States)

    Karantonis, Dean M; Mason, David G; Salamonsen, Robert F; Ayre, Peter J; Cloherty, Shaun L; Lovell, Nigel H

    2007-01-01

    An integral component in the development of a control strategy for implantable rotary blood pumps is the task of reliably detecting the occurrence of left ventricular collapse due to overpumping of the native heart. Using the noninvasive pump feedback signal of impeller speed, an approach to distinguish between overpumping (or ventricular collapse) and the normal pumping state has been developed. Noninvasive pump signals from 10 human pump recipients were collected, and the pumping state was categorized as either normal or suction, based on expert opinion aided by transesophageal echocardiographic images. A number of indices derived from the pump speed waveform were incorporated into a classification and regression tree model, which acted as the pumping state classifier. When validating the model on 12,990 segments of unseen data, this methodology yielded a peak sensitivity/specificity for detecting suction of 99.11%/98.76%. After performing a 10-fold cross-validation on all of the available data, a minimum estimated error of 0.53% was achieved. The results presented suggest that techniques for pumping state detection, previously investigated in preliminary in vivo studies, are applicable and sufficient for use in the clinical environment.

  17. 40 CFR 65.116 - Quality improvement program for pumps.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Quality improvement program for pumps... pumps. (a) Criteria. If, on a 6-month rolling average, at least the greater of either 10 percent of the pumps in a process unit (or plant site) or three pumps in a process unit (or plant site) leak, the...

  18. 40 CFR 63.176 - Quality improvement program for pumps.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Quality improvement program for pumps... improvement program for pumps. (a) In Phase III, if, on a 6-month rolling average, the greater of either 10 percent of the pumps in a process unit (or plant site) or three pumps in a process unit (or plant...

  19. 49 CFR 230.57 - Injectors and feedwater pumps.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Injectors and feedwater pumps. 230.57 Section 230... Appurtenances Injectors, Feedwater Pumps, and Flue Plugs § 230.57 Injectors and feedwater pumps. (a) Water.... Injectors and feedwater pumps must be kept in good condition, free from scale, and must be tested at...

  20. 46 CFR 56.50-55 - Bilge pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Bilge pumps. 56.50-55 Section 56.50-55 Shipping COAST... Design Requirements Pertaining to Specific Systems § 56.50-55 Bilge pumps. (a) Self-propelled vessels. (1) Each self-propelled vessel must be provided with a power-driven pump or pumps connected to the...

  1. 40 CFR 63.1035 - Quality improvement program for pumps.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Quality improvement program for pumps... improvement program for pumps. (a) Criteria. If, on a 6-month rolling average, at least the greater of either 10 percent of the pumps in a process unit or affected facility (or plant site) or three pumps in...

  2. 40 CFR 61.242-2 - Standards: Pumps.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standards: Pumps. 61.242-2 Section 61... (Fugitive Emission Sources) § 61.242-2 Standards: Pumps. (a)(1) Each pump shall be monitored monthly to... (d), (e), (f) and (g) of this section. (2) Each pump shall be checked by visual inspection...

  3. DESIGN RULE FOR PUMPING DEVICES IN A LOOP POLYMERIZATION REACTOR

    NARCIS (Netherlands)

    MOZARYN, W; JANSSEN, LPBM; VANDIERENDONCK, LL

    1994-01-01

    The mutual influence on the pumping capacity of independently driven pumping-stirring devices in a polymerization loop reactor is presented. A simple method for the calculation of the minimum rotational speed for an axial pumping stirrer in relation to the pumping action of a helical ribbon is descr

  4. Livestock water pumping with wind and solar power

    Science.gov (United States)

    Recent developments in pumping technologies have allowed for efficient use of renewable energies like wind and solar to power new pumps for remote water pumping. A helical type, positive displacement pump was developed a few years ago and recently modified to accept input from a variable power sourc...

  5. Routine sensor-augmented pump therapy in type 1 diabetes

    DEFF Research Database (Denmark)

    Nørgaard, Kirsten; Scaramuzza, Andrea; Bratina, Natasa

    2013-01-01

    Sensor-augmented pump (SAP) therapy can improve glycemic control, compared with multiple daily insulin injections or with insulin pump therapy alone, without increasing the risk of hypoglycemia.......Sensor-augmented pump (SAP) therapy can improve glycemic control, compared with multiple daily insulin injections or with insulin pump therapy alone, without increasing the risk of hypoglycemia....

  6. 46 CFR 193.10-5 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... Minimum number of pumps Hose and hydrant size, inches Nozzle orifice size, inches Length of hose, feet 100... tube pressure may not be less than 35 p.s.i. (d) Fire pumps shall be fitted on the discharge side with... this amount. (e) Fire pumps shall be fitted with a pressure gage on the discharge side of the pumps....

  7. A comparison of pumping speed measurement methods

    CERN Document Server

    Denison, D R

    1974-01-01

    A comparison of pumping speed measurement method was made using three types of apparatus. These were: (i) the Fischer-Mommsen system, developed at CERN in which the gas flow rate is measured by the pressure drop across an orifice of known conductance at the test vessel inlet and the pressure gauge is arrayed to serve as a molecular flux transducer, (ii) the three gauge system used by some pump manufacturers in which the gas flow rate is determined by measuring the pressure drop across a long tube whose conductance is calculated from its dimensions and (iii) the constant pressure/pipette system in which the time is measured to evacuate a known quantity of gas. A sputter-ion pump with Ti and Ta cathodes and 32 Penning cells was used as the test pump. The Fischer and Mommsen and pipette procedures gave good agreement for the pumping speeds of N/sub 2/ (within 1%) but allowance had to be made for mass discrimination in the gas flow through an orifice when air was pumped. The three gauge method consistently gave a...

  8. Optimized ground coupled heat pump mechanical package

    Energy Technology Data Exchange (ETDEWEB)

    Catan, M.A.

    1984-01-01

    The system which was optimized was a horizontal earth coil in a given house in the Pittsburgh area. The types of components used in the heat pump are essentially conventional. The method of this study is derived from one used to optimize an air-source heat pump for operation at standard steady state conditions. A computer model, created at Oak Ridge National Laboratory (ORNL), is used to predict heat pump performance for specified configuration and operating conditions. A predetermined set of design parameters is automatically altered by a constrained minimization program (a Numerical Algorithms Group library routine hereafter referred to as the optimizer) to find the combination for which the highest COP is predicted by the heat pump model. In the present study, the set of parameters to be varied include some pertaining to the ground coil as well as some pertaining to the heat pump. The optimizer, in this case, pursues a minimum life cycle cost which is calculated using the heat pump model, a ground coil model (called FTECM for Fast Transient Earth Coil model), and a parameterized cost model. The flow chart shows how the optimizer interacts with these programs to minimize life cycle cost.

  9. Diode pumped Nd:YAG laser development

    Science.gov (United States)

    Reno, C. W.; Herzog, D. G.

    1976-01-01

    A low power Nd:YAG laser was constructed which employs GaAs injection lasers as a pump source. Power outputs of 125 mW TEM CW with the rod at 250 K and the pump at 180 K were achieved for 45 W input power to the pump source. Operation of the laser, with array and laser at a common heat sink temperature of 250 K, was inhibited by difficulties in constructing long-life GaAs LOC laser arrays. Tests verified pumping with output power of 20 to 30 mW with rod and pump at 250 K. Although life tests with single LOC GaAs diodes were somewhat encouraging (with single diodes operating as long as 9000 hours without degradation), failures of single diodes in arrays continue to occur, and 50 percent power is lost in a few hundred hours at 1 percent duty factor. Because of the large recent advances in the state of the art of CW room temperature AlGaAs diodes, their demonstrated lifetimes of greater than 5,000 hours, and their inherent advantages for this task, it is recommended that these sources be used for further CW YAG injection laser pumping work.

  10. Vertical pump turbine oil environmental evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Culver, G.

    1991-04-01

    In Oregon low-temperature geothermal injection well construction, siting and receiving formations requires approval by the Water Resources Department (OWRD). In addition, the Oregon Department of Environmental Quality (ODEQ) has regulations concerning injection. Conversations with the OWRD and ODEQ representatives indicated they were very concerned about the potential for contamination of the geothermal (and cooler but hydraulically connected) aquifers by oils and grease. Their primary concern was over the practice of putting paraffin, motor oils and other hydrocarbons in downhole heat exchanger (DHE) wells to prevent corrosion. They also expressed considerable concern about the use of oil in production well pumps since the fluids pumped would be injected. Oregon (and Idaho) prohibit the use of oil-lubricated pumps for public water supplies except in certain situations where non-toxic food-grade lubricants are used. Since enclosed-lineshaft oil-lubricated pumps are the mainstay of direct-use pumping equipment, the potential for restricting their use became a concern to the Geo-Heat Center staff. An investigation into alternative pump lubrication schemes and development of rebuttals to potential restrictions was proposed and approved as a contract task. (SM)

  11. The SML pump of carbon cycles in oceans

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Zhengbin; GONG; Haidong; LIU; Liansheng

    2006-01-01

    Different from the solution/physical pump, biological pump and continental shelf pump of carbon cycle in oceans, a new pump named "surface microlayer (SML) pump" is developed based on data obtained from marine investigations and lab study. The SML pump has: (1) left-right dissymmetry of "pH-depth" curve; (2) the non-linearity of "concentration-depth" curve; and (3) difference of affecting confine of the SML pump. The issue of "source" or "sink" of atmospheric CO2 in the Yellow Sea and South China Sea is discussed.

  12. Self Calibrating Flow Estimation in Waste Water Pumping Stations

    DEFF Research Database (Denmark)

    Kallesøe, Carsten Skovmose; Knudsen, Torben

    2016-01-01

    Knowledge about where waste water is flowing in waste water networks is essential to optimize the operation of the network pumping stations. However, installation of flow sensors is expensive and requires regular maintenance. This paper proposes an alternative approach where the pumps and the waste...... water pit are used for estimating both the inflow and the pump flow of the pumping station. Due to the nature of waste water, the waste water pumps are heavily affected by wear and tear. To compensate for the wear of the pumps, the pump parameters, used for the flow estimation, are automatically...

  13. Transient two-phase performance of LOFT reactor coolant pumps

    Energy Technology Data Exchange (ETDEWEB)

    Chen, T.H.; Modro, S.M.

    1983-01-01

    Performance characteristics of Loss-of-Fluid Test (LOFT) reactor coolant pumps under transient two-phase flow conditions were obtained based on the analysis of two large and small break loss-of-coolant experiments conducted at the LOFT facility. Emphasis is placed on the evaluation of the transient two-phase flow effects on the LOFT reactor coolant pump performance during the first quadrant operation. The measured pump characteristics are presented as functions of pump void fraction which was determined based on the measured density. The calculated pump characteristics such as pump head, torque (or hydraulic torque), and efficiency are also determined as functions of pump void fractions. The importance of accurate modeling of the reactor coolant pump performance under two-phase conditions is addressed. The analytical pump model, currently used in most reactor analysis codes to predict transient two-phase pump behavior, is assessed.

  14. A review on adsorption heat pump: Problems and solutions

    OpenAIRE

    Demir, Hasan; MOBEDI, Moghtada; Ülkü, Semra

    2008-01-01

    Adsorption heat pumps have considerably sparked attentions in recent years. The present paper covers the working principle of adsorption heat pumps, recent studies on advanced cycles, developments in adsorbent-adsorbate pairs and design of adsorbent beds. The adsorbent-adsorbate pair features for in order to be employed in the adsorption heat pumps are described. The adsorption heat pumps are compared with the vapor compression and absorption heat pumps. The problems and troubles of adsorptio...

  15. Eccentric Pumping Unit: Cost-effective and Reliable

    Institute of Scientific and Technical Information of China (English)

    Zhang Shaobo; Gao Heping; Chen Yibao; Shi Linsong; Zhang Huiwen

    1996-01-01

    @@ The beam-type pumping unit is the most widely used ty pe of pumping unit because of its simple geometry and its reliability. However. when its stroke exceeds five meters, the structure of the unit becomes massive and its cost becomes quite high. In order to make full use of the advantages of the beam pumping unit and to enhance its stroke. a new type of pumping unit - the ECCENTRIC PUMPING UNIT - has been designed after two years of the research work.

  16. VENTRICLE ASSIST DEVICE: PAST, PRESENT, AND FUTURE NONPULSATILE PUMPS

    Directory of Open Access Journals (Sweden)

    G. Р. Itkin

    2009-01-01

    Full Text Available The article briefly describes the history of the non-pulsating type blood pumps for ventricular assist circulation and heart-lung machine. Disclosed the main advantages of these pumps before pulsating type, especially for implantable systems development. However, disadvantages of these pumps and the directions of minimize or eliminate ones have shown. Specific examples of our implantable centrifugal and axial pump developments are presented. Declare the ways to further improve the pumps

  17. Pump/Control System Minimum Operating Cost Testing

    Science.gov (United States)

    1977-01-01

    A preliminary evaluation of pump performance was initiated to determine the efficiencies of an arbitrary group of small pumps. Trends in factors affecting energy usage in typical prime movers which might be used in liquid transport solar systems were assessed. Comparisons of centrifugal pump efficiencies were made from one manufacturer to another. Tests were also made on two positive-displacement pumps and comparisons with centrifugal pumps were observed.

  18. Test Rig Design For Compact Variable Displacement Vane Pump

    OpenAIRE

    Chawla, Pratik; Jenkins, Ryan; Ivantysynova, Monika

    2015-01-01

    Variable displacement vane pumps (VDVP) are one type of positive displacement pumps used in automatic transmission vehicles for lubricating the gears, cooling the transmission and actuating the clutches. Though fixed displacement pumps are widely used, they output a constant effective flow at a given speed. Depending on pump sizing considerations, the pump can be oversized at high speeds because flow demand of the transmission is independent of engine speed. The excess flow returns to the tan...

  19. Design and test of a pump failure anticipator

    Science.gov (United States)

    Frarey, J. L.; Wilson, D. S.; Burchill, R. F.

    1975-01-01

    Tests were conducted on two different types of pumps in order to refine the concept and to finalize design details of a positive displacement internal gear pump and a shroudless centrifugal pump. A concept and a system that could be used with pumps to allow a rapid judgement to be made of the suitability of the pump for futher service is developed. Test results and detailed data analysis are included.

  20. 46 CFR 95.10-5 - Fire pumps.

    Science.gov (United States)

    2010-10-01

    ... pumps Hose and hydrant size, inches Nozzle orifice size, inches Length of hose feet 100 1 1 1 11/2 1 1/2... be only 35 p.s.i. (d) Fire pumps shall be fitted on the discharge side with relief valves set to... pumps shall be fitted with a pressure gage on the discharge side of the pumps. (f) Fire pumps may...