WorldWideScience

Sample records for hydraulic engineer ice

  1. Ice Engineering Research Area

    Data.gov (United States)

    Federal Laboratory Consortium — Refrigerated Physical Modeling of Waterways in a Controlled EnvironmentThe Research Area in the Ice Engineering Facility at the Cold Regions Research and Engineering...

  2. Design of hydraulic output Stirling engine

    Science.gov (United States)

    Toscano, W. M.; Harvey, A. C.; Lee, K.

    1983-01-01

    A hydraulic output system for the RE-1000 free piston stirling engine (FPSE) was designed. The hydraulic output system can be readily integrated with the existing hot section of RE-1000 FPSE. The system has two simply supported diaphragms which separate the engine gas from the hydraulic fluid, a dynamic balance mechanism, and a novel, null center band hydraulic pump. The diaphragms are designed to endure more than 10 billion cycles, and to withstand the differential pressure load as high as 14 MPa. The projected thermodynamic performance of the hydraulic output version of RE-1000 FPSE is 1.87 kW at 29/7 percent brake efficiency.

  3. Image Content Engine (ICE)

    Energy Technology Data Exchange (ETDEWEB)

    Brase, J M

    2007-03-26

    The Image Content Engine (ICE) is being developed to provide cueing assistance to human image analysts faced with increasingly large and intractable amounts of image data. The ICE architecture includes user configurable feature extraction pipelines which produce intermediate feature vector and match surface files which can then be accessed by interactive relational queries. Application of the feature extraction algorithms to large collections of images may be extremely time consuming and is launched as a batch job on a Linux cluster. The query interface accesses only the intermediate files and returns candidate hits nearly instantaneously. Queries may be posed for individual objects or collections. The query interface prompts the user for feedback, and applies relevance feedback algorithms to revise the feature vector weighting and focus on relevant search results. Examples of feature extraction and both model-based and search-by-example queries are presented.

  4. Modeling and Simulation of Hydraulic Engine Mounts

    Institute of Scientific and Technical Information of China (English)

    DUAN Shanzhong; Marshall McNea

    2012-01-01

    Hydraulic engine mounts are widely used in automotive powertrains for vibration isolation.A lumped mechanical parameter model is a traditional approach to model and simulate such mounts.This paper presents a dynamical model of a passive hydraulic engine mount with a double-chamber,an inertia track,a decoupler,and a plunger.The model is developed based on analogy between electrical systems and mechanical-hydraulic systems.The model is established to capture both low and high frequency dynatmic behaviors of the hydraulic mount.The model will be further used to find the approximate pulse responses of the mounts in terms of the force transmission and top chamber pressure.The close form solution from the simplifiod linear model may provide some insight into the highly nonlinear behavior of the mounts.Based on the model,computer simulation has been carried out to study dynamic performance of the hydraulic mount.

  5. Considerations for Stationary Ice Covered Flows in Adaptive Hydraulics (ADH)

    Science.gov (United States)

    2009-05-01

    Flows in Adaptive Hydraulics (ADH) by Gary L. Brown, Gaurav Savant , Charlie Berger, and David S. Smith Report Documentation Page Form ApprovedOMB No...Road, Vicksburg, MS 39180 at 601-634-3628, e-mail: Gary.L.Brown@usace.army.mil, or Dr. Gaurav Savant , P.E., Coastal and Hydraulics Laboratory, U.S...L., G. Savant , C.; Berger, and D. S. Smith. 2009. Considerations for stationary ice covered flows in ADaptive Hydraulics (ADH) ERDC TN-SWWRP- 09-4

  6. The use of asphalt in hydraulic engineering

    NARCIS (Netherlands)

    Van de Velde, P.A.; Ebbens, E.H.; Van Herpen, J.A.

    1985-01-01

    Asphalt products have been used in the Netherlands in hydraulic engineering for a long time on a large scale, especially after the great disaster in 1953 when a large part of western Holland was flooded by the sea. After the disaster a great number of dikes had to be repaired very quickly and this w

  7. Sustainable hydraulic engineering through building with nature

    NARCIS (Netherlands)

    Vriend, de H.J.; Koningsveld, van M.; Aarninkhof, S.G.J.; Vries, de M.B.; Baptist, M.J.

    2015-01-01

    Hydraulic engineering infrastructures are of concern to many people and are likely to interfere with the environment. Moreover, they are supposed to keep on functioning for many years. In times of rapid societal and environmental change this implies that sustainability and adaptability are important

  8. The use of asphalt in hydraulic engineering

    NARCIS (Netherlands)

    Van de Velde, P.A.; Ebbens, E.H.; Van Herpen, J.A.

    1985-01-01

    Asphalt products have been used in the Netherlands in hydraulic engineering for a long time on a large scale, especially after the great disaster in 1953 when a large part of western Holland was flooded by the sea. After the disaster a great number of dikes had to be repaired very quickly and this w

  9. International Institute for Hydraulic and Environmental Engineering

    Science.gov (United States)

    Mostertman, L. J.

    1977-01-01

    Describes the activities of the International Institute for Hydraulic and Environmental Engineering (IHE), whose primary function is the promotion of the better use of water resources as a vehicle of development by the transfer of knowledge and experience. (Author/RK)

  10. Sustainable hydraulic engineering through building with nature

    NARCIS (Netherlands)

    Vriend, de H.J.; Koningsveld, van M.; Aarninkhof, S.G.J.; Vries, de M.B.; Baptist, M.J.

    2015-01-01

    Hydraulic engineering infrastructures are of concern to many people and are likely to interfere with the environment. Moreover, they are supposed to keep on functioning for many years. In times of rapid societal and environmental change this implies that sustainability and adaptability are important

  11. Modeling Commercial Turbofan Engine Icing Risk With Ice Crystal Ingestion

    Science.gov (United States)

    Jorgenson, Philip C. E.; Veres, Joseph P.

    2013-01-01

    The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which are ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in

  12. Basal hydraulic conditions of Ice Stream B

    Science.gov (United States)

    Engelhardt, Hermann; Kamb, Barclay

    1993-01-01

    Fifteen boreholes have been drilled to the base of Ice Stream B in the vicinity of UpB Camp. The boreholes are spread over an area of about 500 x 1000 m. Several till cores were retrieved from the bottom of the 1000-m-deep holes. Laboratory tests using a simple shear box revealed a yield strength of basal till of 2 kPa. This agrees well with in-situ measurements using a shear vane. Since the average basal shear stress of Ice Stream B with a surface slope of 0.1 degree is about 20 kPa, the ice stream cannot be supported by till that weak. Additional support for this conclusion comes from the basal water pressure that has been measured in all boreholes as soon as the hot water drill reached bottom. In several boreholes, the water pressure has been continuously monitored; in two of them, over several years. The water pressure varies but stays within 1 bar of flotation where ice overburden pressure and water pressure are equal. The ratio of water and overburden pressure lies between 0.986 and 1.002. This is an extremely high value as compared to other fast-moving ice masses; e.g., Variegated Glacier in surge has a ratio of 0.8, and Columbia Glacier - a fast-moving tidewater glacier - has a ratio of 0.9. It implies that water flow under the glacier occurs in a thin film and not in conduits that would drain away water too rapidly. It also implies that basal sliding must be very effective. Water flow under the glacier was measured in a salt-injection experiment where a salt pulse was released at the bottom of a borehole while 60 m down-glacier, the electrical resistance was measured between two other boreholes. A flow velocity of 7 mm/s was obtained.

  13. Eulerian method for ice crystal icing in turbofan engines

    NARCIS (Netherlands)

    Norde, Ellen

    2017-01-01

    The newer generations of high-bypass-ratio engines are susceptible to the ingestion of small ice crystals which may cause engine power loss or damage. The research presented in this thesis focusses on the development of a computational method for in-engine ice crystal accretion. The work has been ca

  14. USE OF GEOSYNTHETIC CASINGS IN HYDRAULIC ENGINEERING

    Directory of Open Access Journals (Sweden)

    Piyavskiy Semen Avraamovich

    2012-10-01

    Full Text Available The article covers the use of geosynthetic casings in hydraulic engineering. The authors describe the structure of earth dams that have geosynthetic casings used as the reinforcement of downstream slopes. Results of stability calculations are provided. The authors consider several examples of effective application of advanced geosynthetic materials used in combination with local building materials as structural elements of hydraulic engineering facilities. Their analysis has demonstrated a strong potential and expediency of application of geosynthetic casings in the course of construction and renovation of low-pressure earth dams. The authors have also developed a new structure of an earth dam. The new earth dam has geosynthetic casings used as structural reinforcing elements of the crown and the downstream slope. The dam structure contemplates the overflow of high water. The structural strengths of the proposed solution include a smaller material consumption rate, lower labour intensiveness and cost of the slope reinforcement due to the application of local building materials used to fill the casings, fast and easy depositing of slope reinforcing elements, and high workability of its dismantling for repair purposes. The authors have also completed the analysis of stability of geosynthetic casings of downstream slopes of an earth dam. The analysis has proven high efficiency of a small slope ratio in combination with its anchorage and reinforcement of the downstream toe with the help of high-strength geogrids.

  15. Hydraulics and pneumatics a technician's and engineer's guide

    CERN Document Server

    Parr, Andrew

    1991-01-01

    Hydraulics and Pneumatics: A Technician's and Engineer's Guide provides an introduction to the components and operation of a hydraulic or pneumatic system. This book discusses the main advantages and disadvantages of pneumatic or hydraulic systems.Organized into eight chapters, this book begins with an overview of industrial prime movers. This text then examines the three different types of positive displacement pump used in hydraulic systems, namely, gear pumps, vane pumps, and piston pumps. Other chapters consider the pressure in a hydraulic system, which can be quickly and easily controlled

  16. Preliminary Evaluation of Altitude Scaling for Turbofan Engine Ice Crystal Icing

    Science.gov (United States)

    Tsao, Jen-Ching

    2017-01-01

    Preliminary evaluation of altitude scaling for turbofan engine ice crystal icing simulation was conducted during the 2015 LF11 engine icing test campaign in PSL.The results showed that a simplified approach for altitude scaling to simulate the key reference engine ice growth feature and associated icing effects to the engine is possible. But special considerations are needed to address the facility operation limitation for lower altitude engine icing simulation.

  17. Suspended Decoupler: A New Design of Hydraulic Engine Mount

    OpenAIRE

    J. Christopherson; Mahinfalah, M.; Jazar, Reza N.

    2012-01-01

    Because of the density mismatch between the decoupler and surrounding fluid, the decoupler of all hydraulic engine mounts (HEM) might float, sink, or stick to the cage bounds, assuming static conditions. The problem appears in the transient response of a bottomed-up floating decoupler hydraulic engine mount. To overcome the bottomed-up problem, a suspended decoupler design for improved decoupler control is introduced. The new design does not noticeably affect the mechanism's steady-state beha...

  18. Hydraulics and pneumatics a technician's and engineer's guide

    CERN Document Server

    Parr, Andrew

    2011-01-01

    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. Such movements and manipulations are frequently accomplished by means of devices driven by liquids (hydraulics) or air (pneumatics), the subject of this book. Hydraulics and Pneumatics is written by a practicing process control engineer as a guide to the successful operation of hydraulic and pneumatic systems for all engineers and technicians working with them. Keeping mathematics and theory to a minimum, this practical guide is thorough but accessible to technicians without a

  19. Performance comparison of hydraulic and gravitation HybridICE ...

    African Journals Online (AJOL)

    been developed to effect ice separation from ice slurry. The two types differ in ... and sizes of crystals, the ratio of the surface area to the volume of ice crystal is ... electrical conductivity and diffusion in ice (Baker et al., 2003). Few compounds ...

  20. Hydraulic Model Study of Port Huron Ice Control Structure,

    Science.gov (United States)

    1982-11-01

    upper portion of the solid ice, extending into the lake. The ice conditions at Port Huron range from the presence of only small ice floes at freezeup ...condition would be most prevalent during freezeup or after an ice breakup due to wind action. A conservative time duration over the entire winter season

  1. Development of a river ice jam by a combined heat loss and hydraulic model

    Science.gov (United States)

    Eliasson, J.; Gröndal, G. O.

    2008-11-01

    The heat loss theory and the hydraulic theory for the analysis of the development of wide channel ice jams are discussed and shown. The heat loss theory has been used in Iceland for a long time, while the hydraulic theory largely follows the classical ice-jam build-up theories used in known CFD models. The results are combined in a new method to calculate the maximum thickness and the extent of an ice jam. The results compare favorably to the HEC-RAS model for the development of a very large ice jam in Thjorsa River in Iceland, and have been found in good agreement with historical data, collected where a hydroelectric dam project, Urridafoss, is being planned in the Thjorsa River.

  2. Development of a river ice jam by a combined heat loss and hydraulic model

    Directory of Open Access Journals (Sweden)

    J. Eliasson

    2008-11-01

    Full Text Available The heat loss theory and the hydraulic theory for the analysis of the development of wide channel ice jams are discussed and shown. The heat loss theory has been used in Iceland for a long time, while the hydraulic theory largely follows the classical ice-jam build-up theories used in known CFD models. The results are combined in a new method to calculate the maximum thickness and the extent of an ice jam. The results compare favorably to the HEC-RAS model for the development of a very large ice jam in Thjorsa River in Iceland, and have been found in good agreement with historical data, collected where a hydroelectric dam project, Urridafoss, is being planned in the Thjorsa River.

  3. Engineering applications of pneumatics and hydraulics

    CERN Document Server

    Turner, Ian C

    2014-01-01

    Assuming only the most basic knowledge of the physics of fluids, this book aims to equip the reader with a sound understanding of fluid power systems and their uses in practical engineering. In line with the strongly practical bias of the book, maintenance and trouble-shooting are covered, with particular emphasis on safety systems and regulations.

  4. Mobile hydraulic power supply. Liquid piston Stirling engine pump

    Energy Technology Data Exchange (ETDEWEB)

    Ven, James D. van de [100 Institute Road, Department of Mechanical Engineering, Worcester Polytechnic Institute, Worcester, MA 01609 (United States)

    2009-11-15

    Conventional mobile hydraulic power supplies involve numerous kinematic connections and are limited by the efficiency, noise, and emissions of internal combustion engines. The Stirling cycle possesses numerous benefits such as the ability to operate from any heat source, quiet operation, and high theoretical efficiency. The Stirling engine has seen limited success due to poor heat transfer in the working chambers, difficulty sealing low-molecular weight gases at high pressure, and non-ideal piston displacement profiles. As a solution to these limitations, a liquid piston Stirling engine pump is proposed. The liquid pistons conform to irregular volumes, allowing increased heat transfer through geometry features on the interior of the working chambers. Creating near-isothermal operation eliminates the costly external heat exchangers and increases the engine efficiency through decreasing the engine dead space. The liquid pistons provide a positive gas seal and thermal transport to the working chambers. Controlling the flow of the liquid pistons with valves enables matching the ideal Stirling cycle and creates a direct hydraulic power supply. Using liquid hydrogen as a fuel source allows cooling the compression side of the engine before expanded the fuel into a gas and combusting it to heat the expansion side of the engine. Cooling the compression side not only increases the engine power, but also significantly increases the potential thermal efficiency of the engine. A high efficiency Stirling engine makes energy regeneration through reversing the Stirling cycle practical. When used for regeneration, the captured energy can be stored in thermal batteries, such as a molten salt. The liquid piston Stirling engine pump requires further research in numerous areas such as understanding the behavior of the liquid pistons, modeling and optimization of a full engine pump, and careful selection of materials for the extreme operating temperatures. Addressing these obtainable

  5. Linear hydraulic drive system for a Stirling engine

    Science.gov (United States)

    Walsh, Michael M.

    1984-02-21

    A hydraulic drive system operating from the periodic pressure wave produced by a Stirling engine along a first axis thereof and effecting transfer of power from the Stirling engine to a load apparatus therefor and wherein the movable, or working member of the load apparatus is reciprocatingly driven along an axis substantially at right angles to the first axis to achieve an arrangement of a Stirling engine and load apparatus assembly which is much shorter and the components of the load apparatus more readily accessible.

  6. Optimization of Classical Hydraulic Engine Mounts Based on RMS Method

    Directory of Open Access Journals (Sweden)

    J. Christopherson

    2005-01-01

    Full Text Available Based on RMS averaging of the frequency response functions of the absolute acceleration and relative displacement transmissibility, optimal parameters describing the hydraulic engine mount are determined to explain the internal mount geometry. More specifically, it is shown that a line of minima exists to define a relationship between the absolute acceleration and relative displacement transmissibility of a sprung mass using a hydraulic mount as a means of suspension. This line of minima is used to determine several optimal systems developed on the basis of different clearance requirements, hence different relative displacement requirements, and compare them by means of their respective acceleration and displacement transmissibility functions. In addition, the transient response of the mount to a step input is also investigated to show the effects of the optimization upon the time domain response of the hydraulic mount.

  7. Ice Jams in Alaska. Ice Engineering. Number 16, February 1997

    Science.gov (United States)

    1997-02-01

    An ice jam is an accumulation of ice in rivers that restricts flow and can cause destructive floods costly to riv- erine communities. Freezeup jams...and reliable data on past ice jam events. The CRREL Ice Jam Database is such a com- pilation of freezeup and breakup ice jam events in the United

  8. Ice Crystal Icing Engine Testing in the NASA Glenn Research Center's Propulsion Systems Laboratory: Altitude Investigation

    Science.gov (United States)

    Oliver, Michael J.

    2014-01-01

    The National Aeronautics and Space Administration (NASA) conducted a full scale ice crystal icing turbofan engine test using an obsolete Allied Signal ALF502-R5 engine in the Propulsion Systems Laboratory (PSL) at NASA Glenn Research Center. The test article used was the exact engine that experienced a loss of power event after the ingestion of ice crystals while operating at high altitude during a 1997 Honeywell flight test campaign investigating the turbofan engine ice crystal icing phenomena. The test plan included test points conducted at the known flight test campaign field event pressure altitude and at various pressure altitudes ranging from low to high throughout the engine operating envelope. The test article experienced a loss of power event at each of the altitudes tested. For each pressure altitude test point conducted the ambient static temperature was predicted using a NASA engine icing risk computer model for the given ambient static pressure while maintaining the engine speed.

  9. Encouraging the Learning of Hydraulic Engineering Subjects in Agricultural Engineering Schools

    Science.gov (United States)

    Sinobas, Leonor Rodríguez; Sánchez Calvo, Raúl

    2014-01-01

    Several methodological approaches to improve the understanding and motivation of students in Hydraulic Engineering courses have been adopted in the Agricultural Engineering School at Technical University of Madrid. During three years student's progress and satisfaction have been assessed by continuous monitoring and the use of…

  10. Encouraging the Learning of Hydraulic Engineering Subjects in Agricultural Engineering Schools

    Science.gov (United States)

    Sinobas, Leonor Rodríguez; Sánchez Calvo, Raúl

    2014-01-01

    Several methodological approaches to improve the understanding and motivation of students in Hydraulic Engineering courses have been adopted in the Agricultural Engineering School at Technical University of Madrid. During three years student's progress and satisfaction have been assessed by continuous monitoring and the use of…

  11. 14 CFR 23.929 - Engine installation ice protection.

    Science.gov (United States)

    2010-01-01

    ... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant General § 23.929 Engine installation ice protection. Propellers (except wooden propellers) and...

  12. A solenoid-based active hydraulic engine mount: modelling, analysis, and verification

    OpenAIRE

    Hosseini, Ali

    2010-01-01

    The focus of this thesis is on the design, modelling, identification, simulation, and experimental verification of a low-cost solenoid-based active hydraulic engine mount. To build an active engine mount, a commercial On-Off solenoid is modified to be used as an actuator and it is embedded inside a hydraulic engine mount. The hydraulic engine mount is modelled and tested, solenoid actuator is modelled and identified, and finally the models were integrated to obtain the analytical model of the...

  13. Suspended Decoupler: A New Design of Hydraulic Engine Mount

    Directory of Open Access Journals (Sweden)

    J. Christopherson

    2012-01-01

    Full Text Available Because of the density mismatch between the decoupler and surrounding fluid, the decoupler of all hydraulic engine mounts (HEM might float, sink, or stick to the cage bounds, assuming static conditions. The problem appears in the transient response of a bottomed-up floating decoupler hydraulic engine mount. To overcome the bottomed-up problem, a suspended decoupler design for improved decoupler control is introduced. The new design does not noticeably affect the mechanism's steady-state behavior, but improves start-up and transient response. Additionally, the decoupler mechanism is incorporated into a smaller, lighter, yet more tunable and hence more effective hydraulic mount design. The steady-state response of a dimensionless model of the mount is examined utilizing the averaging perturbation method applied to a set of second-order nonlinear ordinary differential equations. It is shown that the frequency responses of the floating and suspended decoupled designs are similar and functional. To have a more realistic modeling, utilizing nonlinear finite elements in conjunction with a lumped parameter modeling approach, we evaluate the nonlinear resorting characteristics of the components and implement them in the equations of motion.

  14. Hydraulic engine valve actuation system including independent feedback control

    Science.gov (United States)

    Marriott, Craig D

    2013-06-04

    A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

  15. Hydraulics.

    Science.gov (United States)

    Decker, Robert L.; Kirby, Klane

    This curriculum guide contains a course in hydraulics to train entry-level workers for automotive mechanics and other fields that utilize hydraulics. The module contains 14 instructional units that cover the following topics: (1) introduction to hydraulics; (2) fundamentals of hydraulics; (3) reservoirs; (4) lines, fittings, and couplers; (5)…

  16. Applications of CFD in Hydraulics and River Engineering

    Science.gov (United States)

    Nguyen, Van Thinh; Nestmann, Franz

    2004-02-01

    In this paper, various applications and developments of CFD technology in hydraulics and river engineering are presented. Numerical studies of three-dimensional turbulent flow fields in open channels and rivers are carried out by CFD packages such as the finite element code FIDAP and finite volume code COMET. Meshing procedures are implemented by GAMBIT or CFD-GEOM. To calculate the position of the free surface two methods are applied, free surface tracking and volume-of-fluid, and some comparisons of these methods are discussed.

  17. Applications of CFD in hydraulics and river engineering

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, V.T.; Nestmann, F. [Univ. of Karlsruhe, Civil Engineering, Karlsruhe (Germany)]. E-mail: ge27@rz.uni-karlsruhe.de; Franz.Nestmann@iwk.uni-karlsruhe.de

    2002-07-01

    In this paper various applications and developments of CFD technology in hydraulics and river engineering are presented. Numerical studies of three dimensional turbulent flow fields in open channels and rivers are carried out by CFD packages such as finite element FIDAP of Fluent and finite volume COMET of ICCM (Institute of Computational Continuum Mechanics GmbH). Meshing procedures are implemented by GAMBIT (Fluent) or CFD-GEOM (CFDRC). Especially, to calculate the position of the free surface both methods, free surface tracking and Volume-Of-Fluid (VOF), are applied. (author)

  18. Engine Icing Data - An Analytics Approach

    Science.gov (United States)

    Fitzgerald, Brooke A.; Flegel, Ashlie B.

    2017-01-01

    Engine icing researchers at the NASA Glenn Research Center use the Escort data acquisition system in the Propulsion Systems Laboratory (PSL) to generate and collect a tremendous amount of data every day. Currently these researchers spend countless hours processing and formatting their data, selecting important variables, and plotting relationships between variables, all by hand, generally analyzing data in a spreadsheet-style program (such as Microsoft Excel). Though spreadsheet-style analysis is familiar and intuitive to many, processing data in spreadsheets is often unreproducible and small mistakes are easily overlooked. Spreadsheet-style analysis is also time inefficient. The same formatting, processing, and plotting procedure has to be repeated for every dataset, which leads to researchers performing the same tedious data munging process over and over instead of making discoveries within their data. This paper documents a data analysis tool written in Python hosted in a Jupyter notebook that vastly simplifies the analysis process. From the file path of any folder containing time series datasets, this tool batch loads every dataset in the folder, processes the datasets in parallel, and ingests them into a widget where users can search for and interactively plot subsets of columns in a number of ways with a click of a button, easily and intuitively comparing their data and discovering interesting dynamics. Furthermore, comparing variables across data sets and integrating video data (while extremely difficult with spreadsheet-style programs) is quite simplified in this tool. This tool has also gathered interest outside the engine icing branch, and will be used by researchers across NASA Glenn Research Center. This project exemplifies the enormous benefit of automating data processing, analysis, and visualization, and will help researchers move from raw data to insight in a much smaller time frame.

  19. Validation Ice Crystal Icing Engine Test in the Propulsion Systems Laboratory at NASA Glenn Research Center

    Science.gov (United States)

    Oliver, Michael J.

    2014-01-01

    The Propulsion Systems Laboratory (PSL) is an existing altitude simulation jet engine test facility located at NASA Glenn Research Center in Cleveland, OH. It was modified in 2012 with the integration of an ice crystal cloud generation system. This paper documents the inaugural ice crystal cloud test in PSL--the first ever full scale, high altitude ice crystal cloud turbofan engine test to be conducted in a ground based facility. The test article was a Lycoming ALF502-R5 high bypass turbofan engine, serial number LF01. The objectives of the test were to validate the PSL ice crystal cloud calibration and engine testing methodologies by demonstrating the capability to calibrate and duplicate known flight test events that occurred on the same LF01 engine and to generate engine data to support fundamental and computational research to investigate and better understand the physics of ice crystal icing in a turbofan engine environment while duplicating known revenue service events and conducting test points while varying facility and engine parameters. During PSL calibration testing it was discovered than heated probes installed through tunnel sidewalls experienced ice buildup aft of their location due to ice crystals impinging upon them, melting and running back. Filtered city water was used in the cloud generation nozzle system to provide ice crystal nucleation sites. This resulted in mineralization forming on flow path hardware that led to a chronic degradation of performance during the month long test. Lacking internal flow path cameras, the response of thermocouples along the flow path was interpreted as ice building up. Using this interpretation, a strong correlation between total water content (TWC) and a weaker correlation between median volumetric diameter (MVD) of the ice crystal cloud and the rate of ice buildup along the instrumented flow path was identified. For this test article the engine anti-ice system was required to be turned on before ice crystal

  20. Encouraging the learning of hydraulic engineering subjects in agricultural engineering schools

    Science.gov (United States)

    Rodríguez Sinobas, Leonor; Sánchez Calvo, Raúl

    2014-09-01

    Several methodological approaches to improve the understanding and motivation of students in Hydraulic Engineering courses have been adopted in the Agricultural Engineering School at Technical University of Madrid. During three years student's progress and satisfaction have been assessed by continuous monitoring and the use of 'online' and web tools in two undergraduate courses. Results from their application to encourage learning and communication skills in Hydraulic Engineering subjects are analysed and compared to the initial situation. Student's academic performance has improved since their application, but surveys made among students showed that not all the methodological proposals were perceived as beneficial. Their participation in the 'online', classroom and reading activities was low although they were well assessed.

  1. A Target Tracking System for Applications in Hydraulic Engineering

    Institute of Scientific and Technical Information of China (English)

    SHEN Qiaonan; AN Xuehui

    2008-01-01

    A new type of digital video monitoring system (DVMS) named user defined target tracking system (UDTTS), was developed based on the digital image processing (DIP) technology and the practice demands of construction site management in hydraulic engineering. The position, speed, and track of moving targets such as humans and vehicles, which could be calculated by their locations at anytime in images basically, were required for management. The proposed algorithm, dependent on the context-sensitive moving infor- mation of image sequences which was much more than one or two images provided, compared the blobs' properties in current frame to the trajectories of targets in the previous frames and then corresponded them. The processing frame rate is about 10fps with the image 240-by-120 pixels. Experimental results show that position, direction, and speed measurements have an accuracy level compatible with the manual work. The user-define process makes the UDTTS available to the public whenever appropriate.

  2. An engineering based approach for hydraulic computations in river flows

    Science.gov (United States)

    Di Francesco, S.; Biscarini, C.; Pierleoni, A.; Manciola, P.

    2016-06-01

    This paper presents an engineering based approach for hydraulic risk evaluation. The aim of the research is to identify a criteria for the choice of the simplest and appropriate model to use in different scenarios varying the characteristics of main river channel. The complete flow field, generally expressed in terms of pressure, velocities, accelerations can be described through a three dimensional approach that consider all the flow properties varying in all directions. In many practical applications for river flow studies, however, the greatest changes occur only in two dimensions or even only in one. In these cases the use of simplified approaches can lead to accurate results, with easy to build and faster simulations. The study has been conducted taking in account a dimensionless parameter of channels (ratio of curvature radius and width of the channel (R/B).

  3. Task committee on experimental uncertainty and measurement errors in hydraulic engineering: An update

    Science.gov (United States)

    Wahlin, B.; Wahl, T.; Gonzalez-Castro, J. A.; Fulford, J.; Robeson, M.

    2005-01-01

    As part of their long range goals for disseminating information on measurement techniques, instrumentation, and experimentation in the field of hydraulics, the Technical Committee on Hydraulic Measurements and Experimentation formed the Task Committee on Experimental Uncertainty and Measurement Errors in Hydraulic Engineering in January 2003. The overall mission of this Task Committee is to provide information and guidance on the current practices used for describing and quantifying measurement errors and experimental uncertainty in hydraulic engineering and experimental hydraulics. The final goal of the Task Committee on Experimental Uncertainty and Measurement Errors in Hydraulic Engineering is to produce a report on the subject that will cover: (1) sources of error in hydraulic measurements, (2) types of experimental uncertainty, (3) procedures for quantifying error and uncertainty, and (4) special practical applications that range from uncertainty analysis for planning an experiment to estimating uncertainty in flow monitoring at gaging sites and hydraulic structures. Currently, the Task Committee has adopted the first order variance estimation method outlined by Coleman and Steele as the basic methodology to follow when assessing the uncertainty in hydraulic measurements. In addition, the Task Committee has begun to develop its report on uncertainty in hydraulic engineering. This paper is intended as an update on the Task Committee's overall progress. Copyright ASCE 2005.

  4. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal presents a dual approach to the development and certification of an alternative system for ice protection of turbine engine inlets. It combines a new...

  5. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation combines a new generation low power ice protection system with a novel path to certification that is based upon requirements that turbine engines be...

  6. Characterizing supraglacial meltwater channel hydraulics on the Greenland Ice Sheet from in situ observations

    Science.gov (United States)

    Gleason, Colin J.; Smith, Laurence C.; Chu, Vena W.; Legleiter, Carl; Pitcher, Lincoln H.; Overstreet, Brandon T.; Rennermalm, Asa K.; Forster, Richard R.; Yang, Kang

    2016-01-01

    Supraglacial rivers on the Greenland ice sheet (GrIS) transport large volumes of surface meltwater toward the ocean, yet have received relatively little direct research. This study presents field observations of channel width, depth, velocity, and water surface slope for nine supraglacial channels on the southwestern GrIS collected between 23 July and 20 August, 2012. Field sites are located up to 74 km inland and span 494-1485 m elevation, and contain measured discharges larger than any previous in situ study: from 0.006 to 23.12 m3/s in channels 0.20 to 20.62 m wide. All channels were deeply incised with near vertical banks, and hydraulic geometry results indicate that supraglacial channels primarily accommodate greater discharges by increasing velocity. Smaller streams had steeper water surface slopes (0.74-8.83%) than typical in terrestrial settings, yielding correspondingly high velocities (0.40-2.60 m/s) and Froude numbers (0.45-3.11) with supercritical flow observed in 54% of measurements. Derived Manning's n values were larger and more variable than anticipated from channels of uniform substrate, ranging from 0.009 to 0.154 with a mean value of 0.035 +/- 0.027 despite the absence of sediment, debris, or other roughness elements. Ubiquitous micro-depressions in shallow sections of the channel bed may explain some of these roughness values. However, we find that other, unobserved sources of flow resistance likely contributed to these elevated n values: future work should explicitly consider additional sources of flow resistance beyond bed roughness in supraglacial channels. We conclude that hydraulic modelling for these channels must allow for both sub- and supercritical flow, and most importantly must refrain from assuming that all ice-substrate channels exhibit similar hydraulic behavior, especially for Froude numbers and Manning's n. Finally, this study highlights that further theoretical and empirical work on supraglacial channel hydraulics is

  7. Ice Crystal Icing Engine Testing in the NASA Glenn Research Center's Propulsion Systems Laboratory (PSL): Altitude Investigation

    Science.gov (United States)

    Oliver, Michael J.

    2015-01-01

    The National Aeronautics and Space Administration conducted a full scale ice crystal icing turbofan engine test in the NASA Glenn Research Centers Propulsion Systems Laboratory (PSL) Facility in February 2013. Honeywell Engines supplied the test article, an obsolete, unmodified Lycoming ALF502-R5 turbofan engine serial number LF01 that experienced an un-commanded loss of thrust event while operating at certain high altitude ice crystal icing conditions. These known conditions were duplicated in the PSL for this testing.

  8. Teaching Process Engineering Principles Using an Ice Cream Maker

    Science.gov (United States)

    Kaletunc, Gonul; Duemmel, Kevin; Gecik, Christopher

    2007-01-01

    The ice cream laboratory experiment is designed to illustrate and promote discussion of several engineering and science topics including material and energy balances, heat transfer, freezing, mass transfer, mixing, viscosity, and freezing point depression in a sophomore level engineering class. A pre-lab assignment requires the students to develop…

  9. Teaching Process Engineering Principles Using an Ice Cream Maker

    Science.gov (United States)

    Kaletunc, Gonul; Duemmel, Kevin; Gecik, Christopher

    2007-01-01

    The ice cream laboratory experiment is designed to illustrate and promote discussion of several engineering and science topics including material and energy balances, heat transfer, freezing, mass transfer, mixing, viscosity, and freezing point depression in a sophomore level engineering class. A pre-lab assignment requires the students to develop…

  10. Engineered Barrier Systems Thermal-Hydraulic-Chemical Column Test Report

    Energy Technology Data Exchange (ETDEWEB)

    W.E. Lowry

    2001-12-13

    The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M&O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01.

  11. 1st International Conference on Hydraulic Design in Water Resources Engineering : Channels and Channel Control Structures

    CERN Document Server

    1984-01-01

    The development of water resources has proceeded at an amazing speed around the world in the last few decades. The hydraulic engineer has played his part: in constructing much larger artificial channels than ever before, larger and more sophisticated control structures, and systems of irrigation, drainage and water supply channels in which the flow by its nature is complex and unsteady requiring computer-based techniques at both the design and operation stage. It seemed appropriate to look briefly at some of the developments in hydraulic design resulting from this situation. Hence the idea of the Conference was formed. The Proceedings of the Conference show that hydraulic engineers have been able to acquire a very substantial base of design capability from the experience of the period referred to. The most outstanding development to have occurred is in the combination of physical and mathematical modelling, which in hydraulic engineering has followed a parallel path to that in other branches of engineering sc...

  12. Space Shuttle Main Engine control system. [hydraulic actuator with digital control

    Science.gov (United States)

    Seitz, P. F.; Searle, R. F.

    1973-01-01

    The Space Shuttle Main Engine is a reusable, high-performance rocket engine being developed by the Rocketdyne Div. of Rockwell International to satisfy the operational requirements of the Space Shuttle Orbiter Vehicle. The design incorporates a hydraulically actuated, closed-loop servosystem controlled and monitored by a programmable electronic digital controller. The controller accepts vehicle commands for the various engine operational phases, positions the appropriate valves, monitors the engine for the required performance precisions and conditions, and provides redundancy management.

  13. Can regional climate engineering save the summer Arctic sea ice?

    Science.gov (United States)

    Tilmes, S.; Jahn, Alexandra; Kay, Jennifer E.; Holland, Marika; Lamarque, Jean-Francois

    2014-02-01

    Rapid declines in summer Arctic sea ice extent are projected under high-forcing future climate scenarios. Regional Arctic climate engineering has been suggested as an emergency strategy to save the sea ice. Model simulations of idealized regional dimming experiments compared to a business-as-usual greenhouse gas emission simulation demonstrate the importance of both local and remote feedback mechanisms to the surface energy budget in high latitudes. With increasing artificial reduction in incoming shortwave radiation, the positive surface albedo feedback from Arctic sea ice loss is reduced. However, changes in Arctic clouds and the strongly increasing northward heat transport both counteract the direct dimming effects. A 4 times stronger local reduction in solar radiation compared to a global experiment is required to preserve summer Arctic sea ice area. Even with regional Arctic dimming, a reduction in the strength of the oceanic meridional overturning circulation and a shut down of Labrador Sea deep convection are possible.

  14. Distributed optical fiber-based theoretical and empirical methods monitoring hydraulic engineering subjected to seepage velocity

    Science.gov (United States)

    Su, Huaizhi; Tian, Shiguang; Cui, Shusheng; Yang, Meng; Wen, Zhiping; Xie, Wei

    2016-09-01

    In order to systematically investigate the general principle and method of monitoring seepage velocity in the hydraulic engineering, the theoretical analysis and physical experiment were implemented based on distributed fiber-optic temperature sensing (DTS) technology. During the coupling influence analyses between seepage field and temperature field in the embankment dam or dike engineering, a simplified model was constructed to describe the coupling relationship of two fields. Different arrangement schemes of optical fiber and measuring approaches of temperature were applied on the model. The inversion analysis idea was further used. The theoretical method of monitoring seepage velocity in the hydraulic engineering was finally proposed. A new concept, namely the effective thermal conductivity, was proposed referring to the thermal conductivity coefficient in the transient hot-wire method. The influence of heat conduction and seepage could be well reflected by this new concept, which was proved to be a potential approach to develop an empirical method monitoring seepage velocity in the hydraulic engineering.

  15. Dynamic characteristics of Semi-active Hydraulic Engine Mount Based on Fluid-Structure Interaction FEA

    Directory of Open Access Journals (Sweden)

    Tian Jiande

    2015-01-01

    Full Text Available A kind of semi-active hydraulic engine mount is studied in this paper. After careful analysis of its structure and working principle, the FEA simulation of it was divided into two cases. One is the solenoid valve is open, so the air chamber connects to the atmosphere, and Fluid-Structure Interaction was used. Another is the solenoid valve is closed, and the air chamber has pressure, so Fluid-Structure-Gas Interaction was used. The test of this semi-active hydraulic engine mount was carried out to compare with the simulation results, and verify the accuracy of the model. Then the dynamic characteristics-dynamic stiffness and damping angle were analysed by simulation and test. This paper provides theoretical support for the development and optimization of the semi-active hydraulic engine mount.

  16. The 25 kWe solar thermal Stirling hydraulic engine system: Conceptual design

    Science.gov (United States)

    White, Maurice; Emigh, Grant; Noble, Jack; Riggle, Peter; Sorenson, Torvald

    1988-01-01

    The conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to a 11 meter test bed concentrator is documented. A manufacturing cost assessment for 10,000 units per year was made. The design meets all program objectives including a 60,000 hr design life, dynamic balancing, fully automated control, more than 33.3 percent overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk.

  17. Dynamic characteristics of Semi-active Hydraulic Engine Mount Based on Fluid-Structure Interaction FEA

    OpenAIRE

    Tian Jiande; Jiang Xue; Liu Guozheng; Shi Wenku; Liu Baoquan; Ma Meiqin

    2015-01-01

    A kind of semi-active hydraulic engine mount is studied in this paper. After careful analysis of its structure and working principle, the FEA simulation of it was divided into two cases. One is the solenoid valve is open, so the air chamber connects to the atmosphere, and Fluid-Structure Interaction was used. Another is the solenoid valve is closed, and the air chamber has pressure, so Fluid-Structure-Gas Interaction was used. The test of this semi-active hydraulic engine mount was carried ou...

  18. Engineering rhizosphere hydraulics: pathways to improve plant adaptation to drought

    Science.gov (United States)

    Ahmed, Mutez; Zarebanadkouki, Mohsen; Ahmadi, Katayoun; Kroener, Eva; Kostka, Stanley; Carminati, Andrea

    2017-04-01

    Developing new technologies to optimize the use of water in irrigated croplands is of increasing importance. Recent studies have drawn attention to the role of mucilage in shaping rhizosphere hydraulic properties and regulating root water uptake. During drying mucilage keeps the rhizosphere wet and conductive, but upon drying it turns hydrophobic limiting root water uptake. Here we introduced the concept of rhizoligands, defined as additives that 1) rewet the rhizosphere and 2) reduce mucilage swelling hereby reducing the rhizosphere conductivity. We then tested its effect on rhizosphere water dynamics and transpiration. The following experiments were carried out to test if selected surfactants behave as a rhizoligand. We used neutron radiography to monitor water redistribution in the rhizosphere of lupine and maize irrigated with water and rhizoligand solution. In a parallel experiment, we tested the effect of rhizoligand on the transpiration rate of lupine and maize subjected to repeated drying and wetting cycles. We also measured the effect of rhizoligand on the maximum swelling of mucilage and the saturated hydraulic conductivity of soil mixed with various mucilage concentrations. The results were then simulated using a root water uptake model. Rhizoligand treatment quickly and uniformly rewetted the rhizosphere of maize and lupine. Interestingly, rhizoligand also reduced transpiration during drying/wetting cycles. Evaporation from the bare soil was of minor importance. Our hypothesis is that the reduction in transpiration was triggered by the interaction between rhizoligand and mucilage exuded by roots. This hypothesis is supported by the fact that rhizoligand reduced the maximum swelling of mucilage, increased its viscosity, and decreased the hydraulic conductivity of soil-mucilage mixtures. The reduced conductivity of the rhizosphere induced a moderate stress to the plants reducing transpiration. Simulation with a reduced hydraulic conductivity of the

  19. Understanding the Space Shuttle Main Engine Hydraulic Actuation System and Reviewing Its Evolution

    Science.gov (United States)

    McWade, Robert J.; Minor, Robert B.; McNutt, Leslie M.

    2010-01-01

    The complex engine start and thrust control requirements of the Space Shuttle Main Engine (SSME) require unique valve, actuator and control system hardware. The Hydraulic Actuation System (HAS) was designed, developed, and now operates to meet tight engine control requirement limits to assure safe, reliable and correct engine thrust at all times. The actuator is designed to be fail safe and fail operate in the areas where redundancy is important. The HAS has an additional pneumatic operating capability that insures a safe sequential closure of all actuators and propellant valves in the event of the loss of hydraulic system pressure or loss of electrical closed loop control of the actuator. The objective of this paper is to provide a complete description of the actuator s internal operating system, along with its interaction with all SSME system interfaces. Additionally the paper addresses the challenges, problems identified, and corrected, and lessons learned, during the course of the almost 35 years of engine operation.

  20. Understanding the Space Shuttle Main Engine Hydraulic Actuation System and Reviewing Its Evolution

    Science.gov (United States)

    McWade, Robert J.; Minor, Robert B.; McNutt, Leslie M.

    2010-01-01

    The complex engine start and thrust control requirements of the Space Shuttle Main Engine (SSME) require unique valve, actuator and control system hardware. The Hydraulic Actuation System (HAS) was designed, developed, and now operates to meet tight engine control requirement limits to assure safe, reliable and correct engine thrust at all times. The actuator is designed to be fail safe and fail operate in the areas where redundancy is important. The HAS has an additional pneumatic operating capability that insures a safe sequential closure of all actuators and propellant valves in the event of the loss of hydraulic system pressure or loss of electrical closed loop control of the actuator. The objective of this paper is to provide a complete description of the actuator s internal operating system, along with its interaction with all SSME system interfaces. Additionally the paper addresses the challenges, problems identified, and corrected, and lessons learned, during the course of the almost 35 years of engine operation.

  1. Dynamic characterization of partially saturated engineered porous media and gas diffusion layers using hydraulic admittance

    Science.gov (United States)

    Cheung, Perry; Fairweather, Joseph D.; Schwartz, Daniel T.

    2012-09-01

    Simple laboratory methods for determining liquid water distribution in polymer electrolyte membrane fuel cell gas diffusion layers (GDLs) are needed to engineer better GDL materials. Capillary pressure vs. liquid saturation measurements are attractive, but lack the ability to probe the hydraulic interconnectivity and distribution within the pore structure. Hydraulic admittance measurements of simple capillary bundles have recently been shown to nicely measure characteristics of the free-interfaces and hydraulic path. Here we examine the use of hydraulic admittance with a succession of increasingly complex porous media, starting with a laser-drilled sample with 154 asymmetric pores and progress to the behavior of Toray TGP-H090 carbon papers. The asymmetric laser-drilled sample clearly shows hydraulic admittance measurements are sensitive to sample orientation, especially when examined as a function of saturation state. Finite element modeling of the hydraulic admittance is consistent with experimental measurements. The hydraulic admittance spectra from GDL samples are complex, so we examine trends in the spectra as a function of wet proofing (0% and 40% Teflon loadings) as well as saturation state of the GDL. The presence of clear peaks in the admittance spectra for both GDL samples suggests a few pore types are largely responsible for transporting liquid water.

  2. Modeling of Commercial Turbofan Engine with Ice Crystal Ingestion; Follow-On

    Science.gov (United States)

    Jorgenson, Philip C. E.; Veres, Joseph P.; Coennen, Ryan

    2014-01-01

    The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which is ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in

  3. Modeling of Commercial Turbofan Engine With Ice Crystal Ingestion: Follow-On

    Science.gov (United States)

    Jorgenson, Philip C. E.; Veres, Joseph P.; Coennen, Ryan

    2014-01-01

    The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which is ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in

  4. Ecological Engineering Approaches to Improve Hydraulic Properties of Infiltration Basins Designed for Groundwater Recharge.

    Science.gov (United States)

    Gette-Bouvarot, Morgane; Volatier, Laurence; Lassabatere, Laurent; Lemoine, Damien; Simon, Laurent; Delolme, Cécile; Mermillod-Blondin, Florian

    2015-08-18

    Infiltration systems are increasingly used in urban areas for groundwater recharge. The reduction of sediment permeability by physical and/or biological processes is a major problem in management of infiltration systems often requiring expensive engineering operations for hydraulic performance maintenance. To reduce these costs and for the sake of sustainable development, we proposed to evaluate the ability of ecological engineering approaches to reduce the biological clogging of infiltration basins. A 36-day field-scale experiment using enclosures was performed to test the influences of abiotic (light reduction by shading) and biotic (introduction of the macrophyte Vallisneria spiralis (L.) or the gastropod Viviparus viviparus (Linnaeus, 1758)) treatments to limit benthic biofilm biomass and to maintain or even increase hydraulic performances. We coupled biological characterization of sediment (algal biomass, bacterial abundance, total organic carbon, total nitrogen, microbial enzymatic activity, photosynthetic activity, and photosystem II efficiency) with hydraulic conductivity measurements to assess the effects of treatments on sediment permeability. The grazer Viviparus viviparus significantly reduced benthic biofilm biomass and enhanced hydraulic conductivity. The other treatments did not produce significant changes in hydraulic conductivity although Vallisneria spiralis affected photosynthetic activity of biofilm. Finally, our results obtained with Viviparus viviparus are promising for the development of ecological engineering solutions to prevent biological fouling in infiltration systems.

  5. Free-piston engine-and-hydraulic pump for railway vehicles

    Directory of Open Access Journals (Sweden)

    A. F. Golovchuk

    2013-04-01

    Full Text Available Purpose. The development of the free-piston diesel engine-and-hydraulic pump for the continuously variable hydrostatical transmission of mobile power vehicles. Methodology. For a long time engine builders have been interesting in the problem of developing free piston engines, which have much bigger coefficient of efficiency (40…80%. Such engines don’t have the conversion of reciprocating motion for inner combustion engine piston into rotating motion of crankshaft, from which the engine torque is transferred to the power machine transmission. Free-piston engines of inner combustion don’t have the crank mechanism (CM that significantly reduces mechanical losses for friction. Such engines can be used as compressors. Free-piston engine compressor (FPEC – is a free-piston machine in which energy received from engine’s cylinder is being transferred direct to compressor’s pistons connected with operational pistons of engine without crank mechanism. Part of the pressed air is being consumed for engine cylinder drain and the other part is going to the consumer. Findings. The use of free-piston engines-and-hydraulic pumps as power-transmission plants of power vehicles (diesel locomotives, combine harvester, tractors, cars and other mobile and stationary power installations with the continuously variable transmissions allows cost effectiveness improvement and metal consumption reduction of these vehicles, since the cost effectiveness of FPE is higher by 25-30%, and the metal consumption is lower by 40-50%. Originality. One of the important advantages of the free-piston engines is their simplicity and engine balance. As a result of the crank mechanism absence their construction is much simplified and the vibrations, peculiar to the ordinary engines are eliminated. In such installation the engine pistons are directly connected through the rod to compressor pistons and therefore there are no losses in the bearing bushes. Practical value. The free

  6. Seeking for methodological proposals to motivate students in the learning of hydraulic engineering subjects

    Science.gov (United States)

    Rodriguez-Sinobas, L.; Sánchez Calvo, R.

    2012-04-01

    Hydraulic Engineering courses are one of the toughest among different degrees dealing with agricultural and environmental engineering schools in the Spanish universities. Nowadays, most of these courses are updating and changing to meet the Bologna guidelines set out in the Declaration of 1999. In fact, some universities such us the Technical University of Madrid, have developed an educational guide highlighting the priorities to meet the new standards on education. This guide set up a framework to be followed by all professors. This work presents different methodological approaches to improve the understanding and motivation of students in Hydraulic Engineering courses in the Agriculture Engineering School of Madrid. During three years student progress and satisfaction have been assessed by continuous monitoring strategies and the use of "on-line" tools. Surveys made among the students show that not of the new methodological proposals were perceived as beneficial, even though some of the very new "on-line" tools were rejected.

  7. System and method for controlling engine knock using electro-hydraulic valve actuation

    Science.gov (United States)

    Brennan, Daniel G

    2013-12-10

    A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

  8. 3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

    Institute of Scientific and Technical Information of China (English)

    ZHONG DengHua; LI MingChao; LIU Jie

    2007-01-01

    Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric engineering geology, a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then, according to the classified thought of the object-oriented technique, the different 3D models of geological and engineering objects were realized based on the data structure, including terrain class,strata class, fault class, and limit class; and the modeling mechanism was alternative. Finally, the 3D integrated model was established by Boolean operations between 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification, the arbitrary slicing analysis of the 3D model, the geological analysis of the dam, and underground engineering. They provide powerful theoretical principles and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

  9. 3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric en-gineering geology,a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then,according to the classified thought of the object-oriented technique,the different 3D models of geological and engi-neering objects were realized based on the data structure,including terrain class,strata class,fault class,and limit class;and the modeling mechanism was alterna-tive. Finally,the 3D integrated model was established by Boolean operations be-tween 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification,the arbitrary slicing analysis of the 3D model,the geological analysis of the dam,and underground engineering. They provide powerful theoretical prin-ciples and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

  10. Engineering of frustration in colloidal artificial ice (Conference Presentation)

    Science.gov (United States)

    Ortiz-Ambriz, Antonio; Tierno, Pietro

    2016-09-01

    Artificial spin-ice systems have been used to date as microscopic models of frustration induced by lattice topology, as they allow for the direct visualization of spin arrangements and textures. However, the engineering of frustrated ice states in which individual spins can be manipulated in situ and the real-time observation of their collective dynamics remain both challenging tasks. Recently, an analogue system has been proposed theoretically, where an optical landscape confined colloidal particles that interacted electrostatically. Here we realize experimentally another version of a colloidal artificial ice system using interacting magnetically polarizable particles confined to lattices of bistable gravitational traps. We show quantitatively that ice-selection rules emerge in this frustrated soft matter system by tuning the strength of the pair-interactions between the microscopic units. By using optical tweezers, we can control particle positioning and dipolar coupling, we introduce monopole-like defects and strings and use loops with defined chirality as an elementary unit to store binary information.

  11. Hydraulic fluids and jet engine oil: pyrolysis and aircraft air quality.

    Science.gov (United States)

    van Netten, C; Leung, V

    2001-01-01

    Incidents of smoke in aircraft cabins often result from jet engine oil and/or hydraulic fluid that leaks into ventilation air, which can be subjected to temperatures that exceed 500 degrees C. Exposed flight-crew members have reported symptoms, including dizziness, nausea, disorientation, blurred vision, and tingling in the legs and arms. In this study, the authors investigated pyrolysis products of one jet engine oil and two hydraulic fluids at 525 degrees C. Engine oil was an important source of carbon monoxide. Volatile agents and organophosphate constituents were released from all the agents tested; however, the neurotoxin trimethyl propane phosphate was not found. The authors hypothesized that localized condensation of pyrolysis products in ventilation ducts, followed by mobilization when cabin heat demand was high, accounted for mid-flight incidents. The authors recommended that carbon monoxide data be logged continuously to capture levels during future incidents.

  12. Free-piston Stirling hydraulic engine and drive system for automobiles

    Science.gov (United States)

    Beremand, D. G.; Slaby, J. G.; Nussle, R. C.; Miao, D.

    1982-01-01

    The calculated fuel economy for an automotive free piston Stirling hydraulic engine and drive system using a pneumatic accumulator with the fuel economy of both a conventional 1980 spark ignition engine in an X body class vehicle and the estimated fuel economy of a 1984 spark ignition vehicle system are compared. The results show that the free piston Stirling hydraulic system with a two speed transmission has a combined fuel economy nearly twice that of the 1980 spark ignition engine - 21.5 versus 10.9 km/liter (50.7 versus 25.6 mpg) under comparable conditions. The fuel economy improvement over the 1984 spark ignition engine was 81 percent. The fuel economy sensitivity of the Stirling hydraulic system to system weight, number of transmission shifts, accumulator pressure ratio and maximum pressure, auxiliary power requirements, braking energy recovery, and varying vehicle performance requirements are considered. An important finding is that a multispeed transmission is not required. The penalty for a single speed versus a two speed transmission is about a 12 percent drop in combined fuel economy to 19.0 km/liter (44.7 mpg). This is still a 60 percent improvement in combined fuel economy over the projected 1984 spark ignition vehicle.

  13. Some Recent Advances on Ice Related Problems in Offshore Engineering

    Institute of Scientific and Technical Information of China (English)

    段梦兰; 刘杰鸣; 樊晓东; 朱守铭; 赵秀菊

    2000-01-01

    This paper deals with several hot topics in ice related problems. In recent years, advances have been made on ice breaking modes, dynamic ice loads on offshore structures, ice-induced structural vibrations, fatigue and fracture by ice-structure interaction, and design of jackets in the Bohai Gulf.

  14. Conceptual design and cost analysis of hydraulic output unit for 15 kW free-piston Stirling engine

    Science.gov (United States)

    White, M. A.

    1982-01-01

    A long-life hydraulic converter with unique features was conceptually designed to interface with a specified 15 kW(e) free-piston Stirling engine in a solar thermal dish application. Hydraulic fluid at 34.5 MPa (5000 psi) is produced to drive a conventional hydraulic motor and rotary alternator. Efficiency of the low-maintenance converter design was calculated at 93.5% for a counterbalanced version and 97.0% without the counterbalance feature. If the converter were coupled to a Stirling engine with design parameters more typcial of high-technology Stirling engines, counterbalanced converter efficiency could be increased to 99.6%. Dynamic computer simulation studies were conducted to evaluate performance and system sensitivities. Production costs of the complete Stirling hydraulic/electric power system were evaluated at $6506 which compared with $8746 for an alternative Stirling engine/linear alternator system.

  15. 75 FR 37311 - Airplane and Engine Certification Requirements in Supercooled Large Drop, Mixed Phase, and Ice...

    Science.gov (United States)

    2010-06-29

    ... certain transport category airplanes certified for flight in icing conditions and the icing airworthiness... charged with promoting safe flight of civil aircraft in air commerce by prescribing minimum standards... million annually) Costs Nominal cost PV cost Engine Cert Cost 7,936,000 6,931,610 Engine Capital Cost 6...

  16. Numerical investigation on super-cooled large droplet icing of fan rotor blade in jet engine

    Science.gov (United States)

    Isobe, Keisuke; Suzuki, Masaya; Yamamoto, Makoto

    2014-10-01

    Icing (or ice accretion) is a phenomenon in which super-cooled water droplets impinge and accrete on a body. It is well known that ice accretion on blades and vanes leads to performance degradation and has caused severe accidents. Although various anti-icing and deicing systems have been developed, such accidents still occur. Therefore, it is important to clarify the phenomenon of ice accretion on an aircraft and in a jet engine. However, flight tests for ice accretion are very expensive, and in the wind tunnel it is difficult to reproduce all climate conditions where ice accretion can occur. Therefore, it is expected that computational fluid dynamics (CFD), which can estimate ice accretion in various climate conditions, will be a useful way to predict and understand the ice accretion phenomenon. On the other hand, although the icing caused by super-cooled large droplets (SLD) is very dangerous, the numerical method has not been established yet. This is why SLD icing is characterized by splash and bounce phenomena of droplets and they are very complex in nature. In the present study, we develop an ice accretion code considering the splash and bounce phenomena to predict SLD icing, and the code is applied to a fan rotor blade. The numerical results with and without the SLD icing model are compared. Through this study, the influence of the SLD icing model is numerically clarified.

  17. An uncoupled multiphase approach towards modeling ice crystals in jet engines

    Science.gov (United States)

    Nilamdeen, Mohamed Shezad

    A recent series of high altitude turbofan engine malfunctions, characterized by flameout and sudden power losses have been reported in recent years. The source of these incidents has been hypothesized to be due to the presence of ice crystals at high altitudes. Ice crystals have been shown to have ballistic trajectories and consequently enter the core engine flow, without getting centrifuged out towards the engine bypass as droplets do. The crystals may melt as they move downstream to higher temperatures in successive stages, or hit a heated surface. The wetted surface may then act as an interface for further crystal impingement, which locally reduces the temperature and could lead to an ice accretion on the components. Ice can accrete to dangerously high levels, causing compressor surge due to blockage of the primary flowpath, vibrational instabilities due to load imbalances of ice on rotating components, mechanical damage of components downstream due to large shed ice fragments, or performance losses if ice enters the combustor, causing a decreased burner efficiency and an eventual flame-out. In order to provide a numerical tool to analyze such situations, FENSAP-ICE has been extended to model mixed-phase flows that combine air, water and ice crystals, and the related ice accretion. DROP3D has been generalized to calculate particle impingement, concentration, and field velocities in an uncoupled approach that neglects any phase change by assuming both ice crystals and supercooled droplets are in thermodynamic equilibrium. ICE3D then accounts for the contribution of ice crystals that stick and melt on an existing water-film and promote ice accretion. The extended ice crystal impingement and ice accretion model has been validated against test data from Cox and Co. and National Research Council icing tests conducted on a NACA0012 airfoil and unheated non-rotating cylinder respectively. The tests show a consistent agreement with respect to experimental profiles in

  18. Report on the ICES subsystem FLOWS

    NARCIS (Netherlands)

    Booij, N.

    1980-01-01

    FLOWS is a recently developed ICES subsystem for applications in the field of hydraulic engineering. It is able to compute steady as well as unsteady flows in hydraulic networks of given dimensions. This means that is does not optimize any parameters describing the network. The network may be compos

  19. Implementation of knowledge-based engineering methodology in hydraulic generator design

    Directory of Open Access Journals (Sweden)

    Wei Guo

    2015-05-01

    Full Text Available Hydraulic generator design companies are always being exhorted to become more competitive by reducing the lead time and costs for their products for survival. Knowledge-based engineering technology is a rapidly developing technology with competitive advantage for design application to reduce time and cost in product development. This article addresses the structure of the hydraulic generator design system based on the knowledge-based engineering technology in detail. The system operates by creating a unified knowledge base to store the scattered knowledge among the whole life of the design process, which was contained in the expert’s brain and technical literature. It helps designers to make appropriate decisions by supplying necessary information at the right time through query and inference engine to represent the knowledge within the knowledge-based engineering application framework. It also integrates the analysis tools into one platform to help achieve global optimum solutions. Finally, an example of turbine-type selection was given to illustrate the operation process and prove its validity.

  20. Performance degradation of a typical twin engine commuter type aircraft in measured natural icing conditions

    Science.gov (United States)

    Ranaudo, R. J.; Mikkelsen, K. L.; Mcknight, R. C.; Perkins, P. J., Jr.

    1984-01-01

    The performance of an aircraft in various measured icing conditions was investigated. Icing parameters such as liquid water content, temperature, cloud droplet sizes and distributions were measured continuously while in icinig. Flight data wre reduced to provide plots of the aircraft drag polars and lift curves (CL vs. alpha) for the measured 'iced' condition as referenced to the uniced aircraft. These data were also reduced to provide plots of thrust horsepower required vs. single engine power available to show how icing affects engine out capability. It is found that performance degradation is primarily influenced by the amount and shape of the accumulated ice. Glaze icing caused the greatest aerodynamic performance penalties in terms of increased drag and reduction in lift while aerodynamic penalties due to rime icing were significantly lower. Previously announced in STAR as N84-13173

  1. Performance Survey of Inflatable Dams in Ice-Affected Waters. Ice Engineering. Number 30, October 2001

    Science.gov (United States)

    2001-10-01

    67 Village of Swanton, VT Hydro (9.8 MW) Highest inflatable dam in the world. Excellent per- formance in ice. Eliminated freezeup and breakup ice...frazil production and subsequent freezeup or breakup ice jam flooding. The airbags would rest deflated on the riverbed when unneeded, allowing fish...For example, frazil ice that once collected behind the dam might move downstream to form a freezeup ice jam and flooding at an undesirable location

  2. Velocity Potential in Engineering Hydraulics versus Force Potential in Groundwater Dynamics

    Science.gov (United States)

    Weyer, K.

    2013-12-01

    Within engineering practice, the calculation of subsurface flow is dominated by the mathematical pseudo-physics of the engineer's adaptation of continuum methods to mechanics. Continuum mechanics rose to prominence in the 19th century in an successful attempt to solve practical engineering problems. To that end were put in place quite a number of simplifications in geometry and the properties of water and other fluids, as well as simplifications of Darcy's equation, in order to find reasonable answers to practical problems by making use of analytical equations. The proof of the correctness of the approach and its usefulness was in the practicability of results obtained. In the 1930s, a diametrically-opposed duality developed in the theoretical derivation of the laws of subsurface fluid flow between Muskat's (1937) velocity potential (engineering hydraulics) and Hubbert's (1940) force potential. The conflict between these authors lasted a lifetime. In the end Hubbert stated on one occasion that Muskat formulates a refined mathematics but does not know what it means in physical terms. In this author's opinion that can still be said about the application of continuum mechanics by engineers to date, as for example to CO2 sequestration, regional groundwater flow, oil sands work, and geothermal studies. To date, engineering hydraulics is best represented by Bear (1972) and de Marsily (1986). In their well-known textbooks, both authors refer to Hubbert's work as the proper way to deal with the physics of compressible fluids. Water is a compressible fluid. The authors then ignore, however, their own insights (de Marsily states so explicitly, Bear does not) and proceed to deal with water as an incompressible fluid. At places both authors assume the pressure gradients to be the main driving force for flow of fluids in the subsurface. That is not, however, the case. Instead the pressure potential forces are caused by compression initiated by unused gravitational energy not

  3. Hydraulic structures

    CERN Document Server

    Chen, Sheng-Hong

    2015-01-01

    This book discusses in detail the planning, design, construction and management of hydraulic structures, covering dams, spillways, tunnels, cut slopes, sluices, water intake and measuring works, ship locks and lifts, as well as fish ways. Particular attention is paid to considerations concerning the environment, hydrology, geology and materials etc. in the planning and design of hydraulic projects. It also considers the type selection, profile configuration, stress/stability calibration and engineering countermeasures, flood releasing arrangements and scouring protection, operation and maintenance etc. for a variety of specific hydraulic structures. The book is primarily intended for engineers, undergraduate and graduate students in the field of civil and hydraulic engineering who are faced with the challenges of extending our understanding of hydraulic structures ranging from traditional to groundbreaking, as well as designing, constructing and managing safe, durable hydraulic structures that are economical ...

  4. A Model to Assess the Risk of Ice Accretion Due to Ice Crystal Ingestion in a Turbofan Engine and its Effects on Performance

    Science.gov (United States)

    Jorgenson, Philip C. E.; Veres, Joseph P.; Wright, William B.; Struk, Peter M.

    2013-01-01

    The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that were attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was one or more of the following anomalies: degraded engine performance, engine roll back, compressor surge and stall, and flameout of the combustor. The main focus of this research is the development of a computational tool that can estimate whether there is a risk of ice accretion by tracking key parameters through the compression system blade rows at all engine operating points within the flight trajectory. The tool has an engine system thermodynamic cycle code, coupled with a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor blade rows. Assumptions are made to predict the complex physics involved in engine icing. Specifically, the code does not directly estimate ice accretion and does not have models for particle breakup or erosion. Two key parameters have been suggested as conditions that must be met at the same location for ice accretion to occur: the local wet-bulb temperature to be near freezing or below and the local melt ratio must be above 10%. These parameters were deduced from analyzing laboratory icing test data and are the criteria used to predict the possibility of ice accretion within an engine including the specific blade row where it could occur. Once the possibility of accretion is determined from these parameters, the degree of blockage due to ice accretion on the local stator vane can be estimated from an empirical model of ice growth rate and time spent at that operating point in the flight trajectory. The computational tool can be used to assess specific turbine engines to their susceptibility to

  5. Engineering and Design: Ice-Influenced Flood Stage Frequency Analysis

    Science.gov (United States)

    1991-07-31

    ETL 1110-2-325 31Ju1 91 freezeup jams, formed by the collection of pieces of floating ice during the pe- riods of relatively steady flow experienced...the potential for gage freezeup because of cold weather, ice effects on the gage rat- ing curve, the location of the gage relative to the ice...project, it may be necessary to split the sample population into two or more subsets, such as open water, freezeup , solid ice cover, and breakup. (1

  6. Ice Events in the St. Louis District. Ice Engineering, Number 20, February 1999

    Science.gov (United States)

    1999-02-01

    primarily breakup ice events, no events within the District are specifically identified as breakup events, while 29 are classified freezeup jams. The...75 ice events listed as being “closure” events (when the ice cover freezes at St. Louis) are thought to be primarily due to freezeup pro- cesses. The

  7. Ice Jams, Winter 2000-2001. Ice Engineering. Number 12, December 2001

    Science.gov (United States)

    2001-12-01

    flow ( freezeup jam), and also form when the ice cover breaks up and clogs the river downstream (breakup jam). When the river becomes jammed with ice... freezeup and breakup ice jam events in the United States (White 1996). There are currently more than 12,500 entries in the database, the earliest

  8. Numerical simulation of two-phase turbulent flow in hydraulic and hydropower engineering

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In connection with the specific features of high velocity aerated flow generated by hydraulic engineering structures,the mathematical model is developed for high turbulence air-water two-phase flow with the use of twin flow theoretical model in this paper.Furthermore the numerical method is proposed to treat bubbled flows.In addition,on the basis of air-water stratified twin flow model,the new calculation methods and free surface tracking technique are proposed to describe complicated movements of the free surface.Finally,the proposed model is used to calculate artificial aerated flows.The computed results coincide quite well with experimental results.This means that the proposed method can provide solid basis for practical engineering design.

  9. DYNAMIC MODEL AND SIMULATION OF A NOVEL ELECTRO-HYDRAULIC FULLY VARIABLE VALVE SYSTEM FOR FOUR-STROKE AUTOMOTIVE ENGINES

    Institute of Scientific and Technical Information of China (English)

    WONG Pak-kin; TAM Lap-mou; LI Ke

    2007-01-01

    In modern four-stroke engine technology, variable valve timing and lift control offers potential benefits for making a high-performance engine. A novel electro-hydraulic fully variable valve train for four-stroke automotive engines is introduced. The construction of the nonlinear mathematic model of the valve train system and its dynamic analysis are also presented. Experimental and simulation results show that the novel electro-hydraulic valve train can achieve fully variable valve timing and lift control. Consequently the engine performance on different loads and speeds will be significantly increased. The technology also permits the elimination of the traditional throttle valve in the gasoline engines and increases engine design flexibility.

  10. Review of Ice-Induced Scour Impacts to Navigation and Structures

    Science.gov (United States)

    2017-07-17

    2015. Hydrotechnical Advances in Canadian River-Ice Science and Engineering during the Past 35 Years. Canadian Journal of Civil Engineering 42 (9...L. Miller, B. C. Burrell, and D. Sullivan. 2007. Hydraulic Effects of Ice Breakup on Bridges. Canadian Journal of Civil Engineering 344:539–548...1988. Damage Resulting from a Sudden River Ice Breakup. Canadian Journal of Civil Engineering 154:609–615. Ettema, R. 2002. Review of Alluvial

  11. Ice Cover Effects on Scour in Narrow Rivers (Ice Engineering, April 2005)

    Science.gov (United States)

    2005-04-01

    responding to changes in water level. In these situations, any increase in the discharge above the level at freezeup will necessarily be accompanied...open water, a floating ice cover, and a restrained ice cover with hydrostatic head conditions simulating discharge increased above freezeup level...responding to changes in discharge conditions. The ice cover forms at the stage corresponding to the freezeup discharge, defining the freezeup datum

  12. Engineering practice for ice force design in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Ottesen Hansen, N.-E. [LICengineering A/S, Copenhagen (Denmark); Gravesen, H. [Carl Bro A/S, Copenhagen (Denmark)

    2001-07-01

    Denmark, the Faroe Islands, and Greenland all come under the umbrella of the Kingdom of Denmark. The ice forces on civil structures vary considerably between the three areas. On a long term average basis, Denmark experiences its straits and seas ice covered every four years. A variation of design ice thickness in the range of 0.6 to 0.9 metres is noted. Polar ice and very large icebergs are common in Greenland, whereas the Faroe Islands, located in the Mid Atlantic, are in deep water and do not experience ice cover during the winter months. The ice loads have an effect on lighthouses and wind turbines, among other structures. Ice-cones are used to reduce the loading which results in increased wave loading. Analysis enables scientists to reach optimum shapes. A considerable dynamic amplification is present and both loads are dynamic. The authors showed that there is an upper limit for ice forces due to limitations in fetch in the constricted Danish waters. They also presented examples of design and trends. 11 refs., 2 tabs., 4 figs.

  13. Jet Engine Powerloss in Ice Particle Conditions: An Aviation Industry Problem

    Science.gov (United States)

    Strapp, J. W.

    2009-09-01

    Since about the 1990, there have been in excess of 100 engine powerloss events in jet aircraft that have now been attributed to the ingestion of ice particles. These powerloss events are observed in essentially all engine types, and on all airframes. Almost all cases have occurred in the vicinity of deep convection usually associated with warm and moist atmospheres. Events have occurred all throughout the world, although there is a somewhat higher concentration in the area of southeast Asia. Powerloss can result from stall, surge, flameout and rollback events in the engine. Many are momentary, with engines relighting automatically, while others require a manual engine relight. In some cases, particularly in rollback cases on smaller commuter-transport aircraft, engine power has only been recovered by melting of ice buildup in the engine below the freezing level. There have been cases of multiple simultaneous engine powerloss, and one case of a landing with no engine power. The frequency of the events, and the potential for multiple-engine powerloss, has led the FAA to note that that these occurrences constitute a significant safety issue. Analysis of the events using aircraft flight data recorder information, pilot interviews, standard meteorological radar and satellite data, and information from several past flight test programs, have led to the conclusion that the powerloss is due to ice buildup in the engine from high concentrations of ice particles in the atmosphere, and that supercooled LWC is not required. This is an unconventional form of icing that had not been previously considered possible by engine designers. The Engine Harmonization Working Group (EHWG), an industry-led committee composed of engine manufacturers, airframe manufacturers, regulators, and government agencies have been studying the powerloss issue since 2004, and have suggested a 4-part technical plan to resolve the issue, which includes improvement of instrumentation to measure high ice

  14. Justification of application of new types of fastening of slopes of hydraulic engineering constructions

    Directory of Open Access Journals (Sweden)

    Smyvalov Anatoly

    2017-01-01

    Full Text Available The article represents the analysis of various types of fastenings of the soil slopes which have found broad application in the hydrotechnical construction practice for the last 10-15 years. It is noted that, generally, new types of fastenings represent composite materials made of concrete, metal and polymers. Experience shows that producers of the construction materials used in bank protection designs seek to recommend them for the solution of a wide range of tasks, at the same time it isn’t always founded. The authors, on the basis of the analysis of experience with the types of fastenings and also modern domestic and foreign recommendations about their design and construction, offer a technique of justification of new types of fastenings of slopes of hydraulic engineering constructions. The use of concrete filled geotextile mats in bank protection is brought out as a practical realization of the represented technique.

  15. Education for hydraulics and pneumatics in Yokohama University, Faculty of Engineering, Department of Mechanical Engineering and Materials Sciences; Yokohama Kokuritsu Daigaku ni okeru yukuatsu kyoiku

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Y. [Yokohama National University, Yokohama (Japan). Faculty of Engineering

    2000-03-15

    Described herein is education for hydraulics and pneumatics in Yokohama University. Department of Mechanical Engineering and Materials Science pursues to most efficiently produce high-quality products useful for human living and compatible with the environments, based on scientific and technological knowledge man has learned. This department has four professional education courses, materials designs, mechanical processes, hot fluid dynamics, and mechanical systems. An independent subject of hydraulic and pneumatic systems is provided for hydraulics and pneumatics. The lectures on mechatronics include those for digitally-, electronically/hydraulically- and electronically/pneumatically-controlled devices, and their characteristics. The related subjects include fluid dynamics, basic fluid analysis, applied fluid analysis, turbo machines, and automatic control. The postgraduate courses provide hydraulic and pneumatic engineering for, e.g., cavitation and unsteady flow through conduits, hydraulic/pneumatic driving and controlling, modeling and robust control of mechanical systems, and designs of fluid-controlling devices and actuators. The experimental courses include tests of centrifugal pump performance, measurement of pressure distributions on journal bearings, and tests of fluid flow through conduits. (NEDO)

  16. Sea Water Quality Modeling in the Frame of a Building First Turn of a Hydraulic Engineering Complex

    Directory of Open Access Journals (Sweden)

    Igor G. Kantargi

    2012-05-01

    Full Text Available The article deals with an application of developed system-dynamic model of the coastal waters quality for an assessment of sea water quality in the frame of building 1 turn of a hydraulic engineering complex "Object" the Island Federation». The attention is paid to a coast site with a coastal protection constructions.

  17. Selected Aspects of Hydraulic Engineering: Liber Amicorum dedicated to Johannes Theodoor Thijsse, on occasion of his retirement as professor

    NARCIS (Netherlands)

    Van Douwen, A.A.

    1963-01-01

    - Biography of Johannes Theodoor Thijsse - British Hydraulic Engineering and Research - Probleme der Donau in Österreich - Évolution, depuis trente ans, de la Normalisation Internationale des Mesures de Débits en Conduite - L' Association Internationale d'Hydrologie Scientifique - Activities of

  18. A Dynamic Model for the Evaluation of Aircraft Engine Icing Detection and Control-Based Mitigation Strategies

    Science.gov (United States)

    Simon, Donald L.; Rinehart, Aidan W.; Jones, Scott M.

    2017-01-01

    Aircraft flying in regions of high ice crystal concentrations are susceptible to the buildup of ice within the compression system of their gas turbine engines. This ice buildup can restrict engine airflow and cause an uncommanded loss of thrust, also known as engine rollback, which poses a potential safety hazard. The aviation community is conducting research to understand this phenomena, and to identify avoidance and mitigation strategies to address the concern. To support this research, a dynamic turbofan engine model has been created to enable the development and evaluation of engine icing detection and control-based mitigation strategies. This model captures the dynamic engine response due to high ice water ingestion and the buildup of ice blockage in the engines low pressure compressor. It includes a fuel control system allowing engine closed-loop control effects during engine icing events to be emulated. The model also includes bleed air valve and horsepower extraction actuators that, when modulated, change overall engine operating performance. This system-level model has been developed and compared against test data acquired from an aircraft turbofan engine undergoing engine icing studies in an altitude test facility and also against outputs from the manufacturers customer deck. This paper will describe the model and show results of its dynamic response under open-loop and closed-loop control operating scenarios in the presence of ice blockage buildup compared against engine test cell data. Planned follow-on use of the model for the development and evaluation of icing detection and control-based mitigation strategies will also be discussed. The intent is to combine the model and control mitigation logic with an engine icing risk calculation tool capable of predicting the risk of engine icing based on current operating conditions. Upon detection of an operating region of risk for engine icing events, the control mitigation logic will seek to change the

  19. Changes in soil hydraulic properties caused by construction of a simulated waste trench at the Idaho National Engineering Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Shakofsky, S.

    1995-03-01

    In order to assess the effect of filled waste disposal trenches on transport-governing soil properties, comparisons were made between profiles of undisturbed soil and disturbed soil in a simulated waste trench. The changes in soil properties induced by the construction of a simulated waste trench were measured near the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory (INEL) in the semiarid southeast region of Idaho. The soil samples were collected, using a hydraulically-driven sampler to minimize sample disruption, from both a simulated waste trench and an undisturbed area nearby. Results show that the undisturbed profile has distinct layers whose properties differ significantly, whereas the soil profile in the simulated waste trench is, by comparison, homogeneous. Porosity was increased in the disturbed cores, and, correspondingly, saturated hydraulic conductivities were on average three times higher. With higher soil-moisture contents (greater than 0.32), unsaturated hydraulic conductivities for the undisturbed cores were typically greater than those for the disturbed cores. With lower moisture contents, most of the disturbed cores had greater hydraulic conductivities. The observed differences in hydraulic conductivities are interpreted and discussed as changes in the soil pore geometry.

  20. 液压发动机在市内公交车上的应用探究%Application Research of Hydraulic Engine on the City Bus

    Institute of Scientific and Technical Information of China (English)

    张超

    2013-01-01

    Brielfy introduce the better performance of hydraulic free piston engine than the traditional internal combustion engine. According to the characteristics of the hydraulic free piston engine and the specialty of bus running, the paper researched the feasibility of hydraulic free piston engine used on the bus. It shows the wide application prospects of hydraulic free piston engine.%简要介绍了液压自由活塞发动机相比于传统内燃机的优越性能,针对液压自由活塞发动机的特点以及公交车运行的特殊性,探究了液压自由活塞发动机在市内公交车上应用的可行性,展现了液压自由活塞发动机的广阔应用前景。

  1. Basic hydraulics

    CERN Document Server

    Smith, P D

    1982-01-01

    BASIC Hydraulics aims to help students both to become proficient in the BASIC programming language by actually using the language in an important field of engineering and to use computing as a means of mastering the subject of hydraulics. The book begins with a summary of the technique of computing in BASIC together with comments and listing of the main commands and statements. Subsequent chapters introduce the fundamental concepts and appropriate governing equations. Topics covered include principles of fluid mechanics; flow in pipes, pipe networks and open channels; hydraulic machinery;

  2. Design and modeling of a hydraulically amplified magnetostrictive actuator for automotive engine mounts

    Science.gov (United States)

    Chakrabarti, Suryarghya; Dapino, Marcelo J.

    2010-04-01

    A model is developed which describes the dynamic response of a Terfenol-D actuator with a hydraulic displacement amplification mechanism for use in active engine mounts. The model includes three main components: magnetic diffusion, Terfenol-D constitutive model, and mechanical actuator model. Eddy current losses are modeled as a one-dimensional magnetic field diffusion problem in cylindrical coordinates. The Jiles-Atherton model is used to describe the magnetization state of the Terfenol-D driver as a function of applied magnetic fields. A quadratic, single-valued model for the magnetostriction dependence on magnetization is utilized which provides an input to the mechanical model describing the system vibrations. Friction at the elastomeric seals is modeled using the LuGre friction model for lubricated contacts. The actuator's dynamic response is quantified in terms of the output displacement in the unloaded condition and force output in the loaded condition. The model is shown to accurately quantify the dynamic behavior of the actuator over the frequency range considered, from near dc to 500 Hz. An order analysis shows that the model also describes the higher harmonic content present in the measured responses. A study on the variation of energy delivered by the actuator with the load stiffness reveals that the actuator delivers the highest energy output near the stiffness match region.

  3. An integrated characteristic simulation method for hydraulically damped rubber mount of vehicle engine

    Science.gov (United States)

    Wang, Li-Rong; Wang, Jia-Cai; Hagiwara, Ichiro

    2005-09-01

    Hydraulically Damped Rubber Mount (HDM) is widely equipped in vehicle powertrain mounting system and plays an important role in noise, vibration and harshness (NVH) control of vehicle. It is necessary that static and dynamic characteristics of HDM and its effectiveness on vibration isolation of powertrain system are predicted at design and development stage. In this paper, a kind of graphic HDM modeling method integrating with parameter identifications obtained from finite element (FE) analysis and experimental analysis is investigated to predict performance of HDM. The fluid-structure interactions in HDM are explored by predictions of volumetric elasticity and equivalent piston area of fluid chamber using a kind of hydrostatic fluid-structure FE method in commercial code of ABAQUS. Predications of static elasticity and dynamic characteristics and frequency response analysis of a typical HDM with fixed-decoupler verify the effectiveness of the proposed method. This research helps automotive engineers to enhance computer-aided system technology in design and development of HDM and powertrain mounting system.

  4. Parameter Identification on Lumped Parameters of the Hydraulic Engine Mount Model

    Directory of Open Access Journals (Sweden)

    Li Qian

    2016-01-01

    Full Text Available Hydraulic Engine Mounts (HEM are important vibration isolation components with compound structure in the vehicle powertrain mounting system. They have the characteristic that large damping and high dynamic stiffness in the high frequency region, and small damping and low dynamic stiffness in the low frequency region, which can meet the requirements of the vehicle powertrain mounting system better. The method to identify the lumped parameters of the HEM is not only the necessary work for the analysis and calculation in dynamic performance and can also provide the theory for the performance optimization and structure optimization of product in the future. The parameter identification method based on coupled fluid-structure interaction (FSI and finite element analysis (FEA was established in this study to identify the equivalent piston area of the rubber spring, the volume stiffness of the upper chamber, as well as the inertia coefficient and damping coefficient of the liquid through the inertia track. The simulated dynamic characteristic curves of the HEM with the parameters identified are in accordance with the measured dynamic characteristic curves well.

  5. Education for hydraulics and pneumatics in Nippon Institute of Technology, Department of Mechanical Engineering; Nippon Kogyo Daigaku ni okeru yukuatsukyoiku

    Energy Technology Data Exchange (ETDEWEB)

    Terashima, Y. [Nippon Institute of Technology, Saitama (Japan)

    2000-03-15

    Described herein is education of hydraulics and pneumatics in Nippon Institute of Technology. Department of Mechanical Engineering has fluid dynamics, mechatronics II, air conditioning, heat transfer engineering, and facility and equipment engineering as the themes related to hydraulics and pneumatics. The control engineering courses have the pneumatics-related themes of supply of pneumatic pressure for a short time and methods for cutting off pneumatic pressure when the piston reaches the dead center, as the energy-saving type driving methods for pneumatic cylinders; measurement of frictional force by the experiments on low-friction cylinders; and researches on improvement of stiffness of pneumatic cylinder type actuators for control valves, among others. Students are directly involved in equipment designs, fabrication and experiments. Many machines and facilities are now easily handled, and operated according to manuals. To prepare graduation theses only by the aid of personal computers is not adequate for education of students in this age, when they have less chances for education through experiences in affluent environments. The mechanical engineering students are given chances for practical education through experiments and graduation thesis preparation. However, it is necessary for general engineering students to be more exposed to technical practices. (NEDO)

  6. Spatial and temporal variability of Arctic summer sea-ice albedo and its dependence on meltwater hydraulics

    Science.gov (United States)

    Eicken, H.; Perovich, D. K.; Grenfell, T. C.; Richter-Menge, J. A.; Frey, K.

    2001-12-01

    Next to ice extent and thickness, the area-averaged albedo of the summer sea-ice cover is a key parameter in determining the large-scale heat exchange over the Arctic Ocean. Various remote sensing applications have yielded a substantial data base for the former two parameters, not least due to the efforts of the National Snow and Ice Data Center (NSIDC) over the past 25 years. In contrast, the spatial and temporal variability of Arctic summer sea-ice albedo is much less well described. Despite its importance (incl. for ice-albedo feedback processes), few if any large-scale sea-ice and global circulation models actually predict summer ice based on the underlying physical processes. Most models employ simple parameterization schemes instead. Remote sensing of surface ice albedo also faces substantial challenges, some of which still need to be addressed in more detail. Here, we report on albedo measurements completed over first- and multi-year sea ice in the summers of 1998, 2000 and 2001 in the North American at the SHEBA drifting ice camp and in fast ice near Barrow, Alaska. As has been established in a number of studies, spatial and temporal variability in summer sea-ice albedo is mostly determined by the areal extent of meltwater ponding at the ice surface. Given the importance of this process, a comprehensive ice hydrological program (meltwater distribution, surface topography, meltwater flow and discharge, ice permeability) has been carried out in conjunction with the optical measurements. Measurements demonstrate that Arctic summer sea-ice albedo is critically dependent on the hydrology of surface melt ponds, as controlled by meltwater production rate, ice permeability and topography. Both, remarkable short-term variability (a reduction of albedo by 43% within two days) as well as the seasonal evolution of the pond fraction and hence area-averaged albedo are forced by changes in pond water level on the order of a few centimeters. While some of these forcing

  7. A study of passive and adaptive hydraulic engine mount systems with emphasis on non-linear characteristics

    Science.gov (United States)

    Kim, G.; Singh, R.

    1995-01-01

    Passive hydraulic mounts exhibit excitation frequency variant and deflection amplitude sensitive stiffness and damping properties. Such non-linear dynamic characteristics are examined by using analytical and experimental methods, both at the device level and within the context of a simplified vehicle model. A new lumped parameter non-linear mathematical model of the hydraulic mount is developed by simulating its decoupler switching mechanism and inertia track dynamics. The low frequency performance features and limitations of several passive mounts are made clear through the non-linear vehicle model simulation and comparable laboratory vibration tests. The high frequency performance problems of the passive hydraulic mount are identified by applying the quasi-linear analysis method. Based on these results, a new adaptive mount system is developed which exhibits broad bandwidth performance features up to 250 Hz. It implements an on-off damping control mode by using engine intake manifold vacuum and a microprocessor based solenoid valve controller. A laboratory bench set-up has already demonstrated its operational feasibility. Through analytical methods, it is observed that our adaptive mount provides superior dynamic performance to passive engine mounts and comparable performance to a small scale active mount over a wide frequency range, given the engine mounting resonance control, shock absorption and vibration isolation performance requirements. Although technical prospects of the proposed adaptive system appear promising, the in situperformance needs to be evaluated.

  8. Control of dense collagen gel scaffolds for tissue engineering through measurement and modelling of hydraulic permeability

    Science.gov (United States)

    Serpooshan, Vahid

    Among various natural biopolymers, type I collagen gels have demonstrated the highest potential as biomimetic scaffolds for tissue engineering (TE). However, the successful application of collagen gels requires a greater understanding of the relationship between their microstructure and physical-mechanical properties. Therefore, a precise method to modulate collagen gel microstructure in order to attain optimal scaffold properties for diverse biomedical applications is necessary. This dissertation describes a new approach to produce collagen gels with defined microstructures, quantified by hydraulic permeability ( k), in order to optimize scaffold properties for TE applications. It was hypothesized that the measurement of k can be used to study the role of microstructure in collagen gel properties, as well as cell function and cell-scaffold interactions. Applying increasing levels of plastic compression (PC) to the highly hydrated collagen gels resulted in an increase in collagen fibrillar density, reduced Happel model derived k values, increased gel stiffness, promoted MSC metabolic activity, osteogenic differentiation, and mineral deposition, while cell-induced gel contraction diminished. Thus, collagen gels with lower k and higher stiffness values exhibited greater potential for bone tissue engineering. Correlating between collagen gel microstructure, k, and fibroblast function within collagen gels indicated that increasing the level of PC yielded a reduction in pore size and an increase in fibril bundle diameter. Decrease in k values resulted in a decrease in gel contraction and an increase in cell metabolic activity. An increase in cell density accelerated contraction. Therefore, fibroblast function within collagen gels can be optimised by a balance between the microstructure, k, and cell seeding density. Developing a micromechanical model to measure experimental k of collagen gels during confined compression revealed the formation of a dense collagen lamella

  9. Modeling of a Turbofan Engine with Ice Crystal Ingestion in the NASA Propulsion System Laboratory

    Science.gov (United States)

    Veres, Joseph P.; Jorgenson, Philip C. E.; Jones, Scott M.; Nili, Samaun

    2017-01-01

    The main focus of this study is to apply a computational tool for the flow analysis of the turbine engine that has been tested with ice crystal ingestion in the Propulsion Systems Laboratory (PSL) at NASA Glenn Research Center. The PSL has been used to test a highly instrumented Honeywell ALF502R-5A (LF11) turbofan engine at simulated altitude operating conditions. Test data analysis with an engine cycle code and a compressor flow code was conducted to determine the values of key icing parameters, that can indicate the risk of ice accretion, which can lead to engine rollback (un-commanded loss of engine thrust). The full engine aerothermodynamic performance was modeled with the Honeywell Customer Deck specifically created for the ALF502R-5A engine. The mean-line compressor flow analysis code, which includes a code that models the state of the ice crystal, was used to model the air flow through the fan-core and low pressure compressor. The results of the compressor flow analyses included calculations of the ice-water flow rate to air flow rate ratio (IWAR), the local static wet bulb temperature, and the particle melt ratio throughout the flow field. It was found that the assumed particle size had a large effect on the particle melt ratio, and on the local wet bulb temperature. In this study the particle size was varied parametrically to produce a non-zero calculated melt ratio in the exit guide vane (EGV) region of the low pressure compressor (LPC) for the data points that experienced a growth of blockage there, and a subsequent engine called rollback (CRB). At data points where the engine experienced a CRB having the lowest wet bulb temperature of 492 degrees Rankine at the EGV trailing edge, the smallest particle size that produced a non-zero melt ratio (between 3 percent - 4 percent) was on the order of 1 micron. This value of melt ratio was utilized as the target for all other subsequent data points analyzed, while the particle size was varied from 1 micron - 9

  10. A Biofilm Treatment Approach for Produced Water from Hydraulic Fracturing Using Engineered Microbial Mats

    Science.gov (United States)

    Akyon, B.; Stachler, E.; Bibby, K. J.

    2015-12-01

    Hydraulic fracturing results in large volumes of wastewater, called "produced water". Treatment of produced water is challenged by its high salt, organic compound, and radionuclide concentrations. Current disposal approaches include deep well injection and physical-chemical treatment for surface disposal; however, deep well injection has been recently linked to induced seismicity and physical-chemical treatments suffer from fouling and high cost. The reuse of the produced water has emerged as a desirable management option; however, this requires pretreatment to generate a water of usable quality and limit microbial activity. Biological treatment is an underexplored area in produced water management and has the potential to remove organics and reduce overall costs for physiochemical treatment or reuse. Suspended growth biological treatment techniques are known to be limited by salinity motivating a more robust biofilm approach: 'microbial mats'. In this study, we used engineered microbial mats as a biofilm treatment for the produced water. Evaluation of the biodegradation performance of microbial mats in synthetic and real produced waters showed microbial activity at up to 100,000 mg/L TDS concentration (three times the salt concentration of the ocean). Organic removal rates reached to 1.45 mg COD/gramwet-day at 91,351 mg/L TDS in real produced water samples and initial evaluation demonstrated the potential for field-scale application. Metagenomic analyses of microbial mats demonstrated an adaptive shift in the microbial community treating different samples, suggesting the wide applicability of this treatment approach for produced waters with varying chemical composition. On-going studies focus on the evaluation of the removal of the organics and the contaminants of high concern in produced water using microbial mats as well as the effect of the biofilm growth conditions on the biodegradation in changing salt concentrations.

  11. The use of Norilsk region’s sulfur and hes ash for hydraulic engineering and reconstruction (rus

    Directory of Open Access Journals (Sweden)

    Lichman N.V.

    2011-12-01

    Full Text Available As a result of the industrial activity millions of tons of industrial wastes are piled in the industrially developed countries. They occupy huge spaces, worsen ecological situation and require proper recovery.The paper contains the information about the ways of technical sulfur and ash recovery from the thermal power station which are used for obtaining artificial fillers and as components in the hydraulic concretes. Comparative characteristics that identify preferential parameters of sulfur concrete with respect to cement concretes are presented. Also the possibility of using technical sulfur and compositions based on it in hydraulic engineering as an anti-screen were investigated. Studies have revealed the fundamental possibility of obtaining high-quality sulfur compounds on the basis of industrial wastes and their field of application was determined.

  12. Reliability and safety of the K Reactor cooling system: Part 2, Engineering analysis of hydraulic and mechanical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Shoemaker, R.H.

    1960-04-04

    Subsequent to the recent formulation and adoption of safety criteria for reactor cooling systems, there appeared the need for an independent evaluation of the safety and reliability of the K-Reactor cooling system in terms of these criteria. The primary, secondary and last-ditch cooling systems of this reactor involve a strong inter-dependence between electrical and hydraulic components of the water plant. Because of the complexity of inter-relationships between these components, the analysis was divided into two parallel studies which were accomplished during the simmer of 1959. F. D. Robbins has presented his analysis of the electrical power and control system in HW-61887. This report deals with an engineering analysis of the hydraulic and mechanical aspects of the reliability and safety of the K-Reactor Cooling System. The system, as described in this report, is that which existed during the simmer of 1959, prior to modification under Project CG-775 (now Project CG-883).

  13. Modelling of a hydraulic engine mount with fluid-structure interaction finite element analysis

    Science.gov (United States)

    Shangguan, Wen-Bin; Lu, Zhen-Hua

    2004-08-01

    Hydraulic engine mount (HEM) is now widely used as a highly effective vibration isolator in automotive powertrain. A lumped parameter (LP) model is a traditional model for modelling the dynamic characteristics of HEM, in which the system parameters are usually obtained by experiments. In this paper, a fluid-structure interaction (FSI) finite element analysis (FEA) method and a non-linear FEA technology are used to determine the system parameters, and a fully coupled FSI model is developed for modelling the static and lower-frequency performance of an HEM. A FSI FEA technique is used to estimate the parameters of volumetric compliances, equivalent piston area, inertia and resistance of the fluid in the inertia track and the decoupler of an HEM. A non-linear FEA method is applied to determine the dynamic stiffness of rubber spring of the HEM. The system parameters predicated by FEA are compared favorably with experimental data and/or analytical solutions. A numerical simulation for an HEM with an inertia track and a free decoupler is performed based on the FSI model and the LP model along with the estimated system parameters, and again the simulation results are compared with experimental data. The calculated time histories of some variables in the model, such as the pressure in the upper chamber, the displacement of the free decoupler and the volume flow through the inertia track and the decoupler, under different excitations, elucidate the working mechanism of the HEM. The pressure distribution calculated with the FSI model in the chambers of the HEM validates the assumption that the pressure distribution in the upper and lower chamber is uniform in the LP model. The work conducted in the paper demonstrates that the methods for estimating the system parameters in the LP model and the FSI model for modelling HEM are effective, with which the dynamic characteristic analysis and design optimization of an HEM can be performed before its prototype development, and this

  14. Apu/hydraulic/actuator Subsystem Computer Simulation. Space Shuttle Engineering and Operation Support, Engineering Systems Analysis. [for the space shuttle

    Science.gov (United States)

    1975-01-01

    Major developments are examined which have taken place to date in the analysis of the power and energy demands on the APU/Hydraulic/Actuator Subsystem for space shuttle during the entry-to-touchdown (not including rollout) flight regime. These developments are given in the form of two subroutines which were written for use with the Space Shuttle Functional Simulator. The first subroutine calculates the power and energy demand on each of the three hydraulic systems due to control surface (inboard/outboard elevons, rudder, speedbrake, and body flap) activity. The second subroutine incorporates the R. I. priority rate limiting logic which limits control surface deflection rates as a function of the number of failed hydraulic. Typical results of this analysis are included, and listings of the subroutines are presented in appendicies.

  15. Advantages of variable-speed operation of hydraulic turbo-engines; Vorteile durch den drehzahlvariablen Betrieb von hydraulischen Stroemungsmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Harbort, T. [Stuttgart Univ. (Germany). Inst. fuer Stroemungsmechanik und Hydraulische Stroemungsmaschinen

    1997-12-31

    The performance of current hydraulic turbo-engines in the variable speed sector is monitored and judged. The study covers radial and axial engines as well as Pelton turbines. Variable-speed operation of hydraulic turbo-engines can be realized by means of different combinations of electrical rotating machines and frequency converters. The operating range of the frequency converter plays an important role in the optimization of performance and is taken into account. The smoothness of run of reaction turbines and their cavitation performance can be enhanced by speed regulation. But above all, efficiency is more or less substantially enhanced during partial load or in the case of greatly varying heights of drop. The latter holds true also of Pelton turbines. (orig.) [Deutsch] Das Betriebsverhalten der gaengigen hydraulischen Stroemungsmaschinen wird in Hinblick auf den drehzahlvariablen Betrieb erfasst und beurteilt. Die Untersuchung erfolgt fuer Radialmaschinen, Axialmaschinen und Peltonturbinen. Der drehzahlvariable Betrieb hydraulischer Stroemungsmaschinen kann mit verschiedenen Kombinationen von elektrischen Maschinen und Frequenzumrichtern realisiert werden. Der Arbeitsbereich des Frequenzumrichters spielt eine wichtige Rolle fuer die Optimierung des Betriebsverhaltens und wird beruecksichtigt. Bei Ueberdruckturbinen kann man durch Drehzahlregelung eine groessere Laufruhe sowie ein guenstigeres Kavitationsverhalten erreichen. Vor allem aber sind im Teillastbereich oder bei stark schwankenden Fallhoehen mehr oder weniger grosse Wirkungsgradgewinne erzielbar. Das letztere gilt auch fuer Peltonturbinen. (orig.)

  16. A fully-coupled geomechanics and flow model for hydraulic fracturing and reservoir engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Charoenwongsa, S.; Kazemi, H.; Miskimins, J.; Fakcharoenphol [Colorado School of Mines, Golden, CO (United States)

    2010-07-01

    A fully coupled geomechanics flow model was used to assess how the changes in pore pressure and temperature influence rock stresses in tight gas reservoirs. The finite difference method was used to develop simulations for phases, components, and thermal stresses. A wave component was used to model the propagation of the strain displacement front as well as changes in stress with time. Fluid and heat flow volumes were modelled separately from rock formation properties. The influence of hydraulic fracturing on stress distributions surrounding the fracture was investigated as well as the effect of filter cake and filtrate. Results of the study showed that significant changes in shear stresses near hydraulic fractures occur as a result of hydraulic fracture face displacement perpendicular to the fracture face. While temperature effects also caused changes in stress distributions, changes in pore pressure did not significantly impact shear stresses as the filtrate did not travel very far into the reservoir. 17 refs., 17 figs.

  17. Handbook of hydraulic fluid technology

    CERN Document Server

    Totten, George E

    2011-01-01

    ""The Handbook of Hydraulic Fluid Technology"" serves as the foremost resource for designing hydraulic systems and for selecting hydraulic fluids used in engineering applications. Featuring new illustrations, data tables, as well as practical examples, this second edition is updated with essential information on the latest hydraulic fluids and testing methods. The detailed text facilitates unparalleled understanding of the total hydraulic system, including important hardware, fluid properties, and hydraulic lubricants. Written by worldwide experts, the book also offers a rigorous overview of h

  18. Proceedings of the 14. workshop of the Committee on River Ice Processes and the Environment : hydraulics of ice covered rivers; Comptes rendus du 14. atelier du Comite sur la glace de riviere et l'environnement : proprietes hydrologiques des cours d'eau geles

    Energy Technology Data Exchange (ETDEWEB)

    Morse, B. [Laval Univ., Quebec City, PQ (Canada). Dept. of Civil Engineering; Bergeron, N.; Gauthier, Y. [Quebec Univ., Quebec, PQ (Canada). Institut National de la Recherche Scientifique-Eau, Terre et Environnement] (comps.)

    2007-07-01

    Ice processes play a significant role in the hydrologic regime of Canadian rivers. The Committee on River Ice Processes and the Environment (CRIPE) identifies high-priority topics for research and development and promotes research programs at Canadian colleges and universities. This workshop reviewed the hydraulic aspects of river ice phenomena in an effort to clarify the effects of ice cover on river flow characteristics. Other issues of concern were also discussed, notably ice formation, ice jams, winter operation of hydroelectric power plants, environmental aspects of river ice, and climate change. The workshop featured 12 poster sessions and 40 presentations, of which 5 have been catalogued separately for inclusion in this database. refs., tabs., figs.

  19. Investigation of Desso GrassMaster® as application in hydraulic engineering

    NARCIS (Netherlands)

    Steeg, van der P.; Paulissen, M.P.C.P.; Roex, E.; Mommer, L.

    2015-01-01

    Dessa GrassMaster® is a reinforced grass system which is applied successfully on sports fields and enables to use a sports field more intensively than a normal grass field. In this report the possibility of an application of Dessa GrassMaster®in hydraulic conditions, with a focus on grass dikes, is

  20. Geologic Controls of Hydraulic Conductivity in the Snake River Plain Aquifer At and Near the Idaho National Engineering and Environmental Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    S. R. Anderson; M. A. Kuntz; L. C. Davis

    1999-02-01

    The effective hydraulic conductivity of basalt and interbedded sediment that compose the Snake River Plain aquifer at and near the Idaho National Engineering and Environmental Laboratory (INEEL) ranges from about 1.0x10 -2 to 3.2x10 4 feet per day (ft/d). This six-order-of-magnitude range of hydraulic conductivity was estimated from single-well aquifer tests in 114 wells, and is attributed mainly to the physical characteristics and distribution of basalt flows and dikes. Hydraulic conductivity is greatest in thin pahoehoe flows and near-vent volcanic deposits. Hydraulic conductivity is least in flows and deposits cut by dikes. Estimates of hydraulic conductivity at and near the INEEL are similar to those measured in similar volcanic settings in Hawaii. The largest variety of rock types and the greatest range of hydraulic conductivity are in volcanic rift zones, which are characterized by numerous aligned volcanic vents and fissures related to underlying dikes. Three broad categories of hydraulic conductivity corresponding to six general types of geologic controls can be inferred from the distribution of wells and vent corridors. Hydraulic conductivity of basalt flows probably is increased by localized fissures and coarse mixtures of interbedded sediment, scoria, and basalt rubble. Hydraulic conductivity of basalt flows is decreased locally by abundant alteration minerals of probable hydrothermal origin. Hydraulic conductivity varies as much as six orders of magnitude in a single vent corridor and varies from three to five orders of magnitude within distances of 500 to 1,000 feet. Abrupt changes in hydraulic conductivity over short distances suggest the presence of preferential pathways and local barriers that may greatly affect the movement of ground water and the dispersion of radioactive and chemical wastes downgradient from points of waste disposal.

  1. Detection of the Impact of Ice Crystal Accretion in an Aircraft Engine Compression System During Dynamic Operation

    Science.gov (United States)

    May, Ryan D.; Simon, Donald L.; Guo, Ten-Huei

    2014-01-01

    The accretion of ice in the compression system of commercial gas turbine engines operating in high ice water content conditions is a safety issue being studied by the aviation community. While most of the research focuses on the underlying physics of ice accretion and the meteorological conditions in which accretion can occur, a systems-level perspective on the topic lends itself to potential near-term operational improvements. Here a detection algorithm is developed which has the capability to detect the impact of ice accretion in the Low Pressure Compressor of an aircraft engine during steady flight as well as during changes in altitude. Unfortunately, the algorithm as implemented was not able to distinguish throttle changes from ice accretion and thus more work remains to be done.

  2. Improvement of diesel engine performance by hydraulically powered electronic control (mechatronics) system. Hakuyo diesel kikan no mechatronics system ni yoru seino kojo

    Energy Technology Data Exchange (ETDEWEB)

    Sonoda, K.; Nakamura, Y.; Kajima, T.; Sato, S.; Fujii, T.; Tobe, Y. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))

    1992-07-20

    This paper describes new hydraulically-actuated mechanisms for both fuel injection and inlet/exhaust valve operation of diesel engines through solenoid valves, which obviate the conventional cam-driven system. These mechanisms were integrated with an electronic control unit also developed in this study and they were mounted as a mechatronics system'' on a power-increased single-cylinder engine. This mechatronics system was mainly composed of an injection control. boost and accumulation component, an inlet and exhaust valve control component, a solenoid valve, an electronic control equipment, a hydraulic power unit, and a maneuvering unit. The verification test was carried out for the improvement of diesel engine performance by the hydraulically powered mechatronics system. As a result, it was proved not only that these mechanisms provide stable operating characteristics over a wide range of conditions, but also that the electronic control system allows accurate, smooth response. 3 refs., 23 figs., 2 tabs.

  3. Operation of a T63 Turbine Engine Using F24 Contaminated Skydrol 5 Hydraulic Fluid

    Science.gov (United States)

    2016-09-01

    T. Edwards (AFRL/RQTF) Engine Mechanical Systems Branch (AFRL/RQTM) Fuels and Energy Branch (AFRL/RQTF) Turbine Engine Division Chris D...MALDONADO, Branch Chief Program Manager Fuels and Energy Branch Fuels and Energy Branch Turbine Engine Division Turbine Engine Division Aerospace...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBEREngine Mechanical Systems Branch (AFRL/RQTM) Fuels and Energy

  4. A simple measuring technique of surface flow velocity to analyze the behavior of velocity fields in hydraulic engineering applications.

    Science.gov (United States)

    Tellez, Jackson; Gomez, Manuel; Russo, Beniamino; Redondo, Jose M.

    2015-04-01

    An important achievement in hydraulic engineering is the proposal and development of new techniques for the measurement of field velocities in hydraulic problems. The technological advances in digital cameras with high resolution and high speed found in the market, and the advances in digital image processing techniques now provides a tremendous potential to measure and study the behavior of the water surface flows. This technique was applied at the Laboratory of Hydraulics at the Technical University of Catalonia - Barcelona Tech to study the 2D velocity fields in the vicinity of a grate inlet. We used a platform to test grate inlets capacity with dimensions of 5.5 m long and 4 m wide allowing a zone of useful study of 5.5m x 3m, where the width is similar of the urban road lane. The platform allows you to modify the longitudinal slopes from 0% to 10% and transversal slope from 0% to 4%. Flow rates can arrive to 200 l/s. In addition a high resolution camera with 1280 x 1024 pixels resolution with maximum speed of 488 frames per second was used. A novel technique using particle image velocimetry to measure surface flow velocities has been developed and validated with the experimental data from the grate inlets capacity. In this case, the proposed methodology can become a useful tools to understand the velocity fields of the flow approaching the inlet where the traditional measuring equipment have serious problems and limitations. References DigiFlow User Guide. (2012), (June). Russo, B., Gómez, M., & Tellez, J. (2013). Methodology to Estimate the Hydraulic Efficiency of Nontested Continuous Transverse Grates. Journal of Irrigation and Drainage Engineering, 139(10), 864-871. doi:10.1061/(ASCE)IR.1943-4774.0000625 Teresa Vila (1), Jackson Tellez (1), Jesus Maria Sanchez (2), Laura Sotillos (1), Margarita Diez (3, 1), and J., & (1), M. R. (2014). Diffusion in fractal wakes and convective thermoelectric flows. Geophysical Research Abstracts - EGU General Assembly 2014

  5. The Great Ice Age cycles associated with the variation of the atmospheric heat engine efficiency

    Institute of Scientific and Technical Information of China (English)

    汤懋苍; 郭维栋

    2000-01-01

    Investigating all the Great Ice Age events throughout the Earth’s history, each was found to follow a strong mountain-making process. Therefore, a hypothesis was put forward with its causality chain as: strong mountain-making process→great disparity in topography on the Earth surface→introducing efficient atmospheric circulation system (plateau monsoon)→increase in global atmospheric heat engine efficiency →generating more atmospheric kinetic energy → enhancing the planetary westerly (under the condition that the huge relief is longitudinal on the whole )→widening the temperature difference between the equator and the polar regions (restrained by the thermal wind law)→sharp cooling in high latitudes and the polars (supposing the solar radiation was approximately constant)→forming a Great Ice Age event.

  6. The Great Ice Age cycles associated with the variation of the atmospheric heat engine efficiency

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Investigating all the Great Ice Age events throughout the Earth's history, each was found to follow a strong mountain-making process. Therefore, a hypothesis was put forward with its causality chain as: strong mountain-making process→great disparity in topography on the Earth surface→introducing efficient atmospheric circulation system (plateau monsoon)→increase in global atmospheric heat engine efficiency→generating more atmospheric kinetic energy→enhancing the planetary westerly (under the condition that the huge relief is longitudinal on the whole )→widening the temperature difference between the equator and the polar regions (restrained by the thermal wind law)→sharp cooling in high latitudes and the polars (supposing the solar radiation was approximately constant)→forming a Great Ice Age event.

  7. The First 75 Years: History of Hydraulics Engineering at the Waterways Experiment Station

    Science.gov (United States)

    2004-01-01

    Rita Robison, "Taming the Red River," Civil Engineering 65 (1995) 6: 64-66. More detail is provided in C. Fred Pinkard , Jr., "Red River Waterway...Engineers. August 14-18, 1995 (New York: American Society of Civil Engineers, 1996), 31-35. 17. See C. Fred Pinkard , Jr. , "Red River Waterway: A...Works for Niagara Falls." In Transactions of the American Society of Civil Engineers 124 (1959): 336-51. Pinkard , C. Fred, Jr. "Red River Waterway

  8. Hydraulic engines in armoured conveyors; Motores hidraulicos en los transportadores blindados

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Fernandez, N.; Fernandez Equibar, J.L. [Hullera Vasco-Leones, S.A., Leon (Spain)

    1994-05-01

    The Sociedad Anonima Hullera Vasco-Leonesa (HVL) coal mining company in Spain is exploiting a deposit of large subvertical seams which are characterised by being highly tectonised. A very important part of the work of exploitation is developed in the depths of the mine with the aid of secondary ventilation. In the near future, which will characterise itself with the opening of the `New Mine`, this type of work will come to have a significant relevance in underground mining technology. The limitations of space and the presence of methane necessitate, as for many years, the use of pneumatic moving shields, with the great inconveniences which derive from them: reduced energy efficiency, and elevated production of dust and noise. For this HVL seek to introduce in a conventional working, at the bottom of the mine, a system of armoured conveyors driven by hydraulic units, which besides reducing and/or eliminating the problems referred to above serve, as in the past, to extend hydraulic energy into other parts of mining activity. In order to initiate the proposed investigation a pilot project will be partially financed by Ocicarbon. 5 figs.

  9. Integrating a piezoelectric actuator with mechanical and hydraulic devices to control camless engines

    Science.gov (United States)

    Mercorelli, Paolo; Werner, Nils

    2016-10-01

    The paper deals with some interdisciplinary aspects and problems concerning the actuation control which occur in the integration of a piezoelectric structure in an aggregate actuator consisting of a piezoelectric, a stroke ratio displacement, a mechanical and a hydraulic part. Problems like compensation of the piezo hysteresis effect, scaling force-position to obtain an adequate displacement of the actuator and finally the control of such a complex aggregate system are considered and solved. Even though this work considers a particular application, the solutions proposed in the paper are quite general. In fact, the considered technical aspects occurring in systems which utilize piezoelectric technologies can be used in a variegated gamma of actuators integrating piezoelectric technologies. A cascade controller is proposed to combine a Feedforward action with an internal and an external PI-Controller. The Feedforward Controller is based on the model of the whole actuator, so particular attention is paid to the model structure. The resulting Feedforward action is an adaptive one to compensate hydraulic pressure faults. Real measurements are shown.

  10. Thermal Hydraulics Design and Analysis Methodology for a Solid-Core Nuclear Thermal Rocket Engine Thrust Chamber

    Science.gov (United States)

    Wang, Ten-See; Canabal, Francisco; Chen, Yen-Sen; Cheng, Gary; Ito, Yasushi

    2013-01-01

    Nuclear thermal propulsion is a leading candidate for in-space propulsion for human Mars missions. This chapter describes a thermal hydraulics design and analysis methodology developed at the NASA Marshall Space Flight Center, in support of the nuclear thermal propulsion development effort. The objective of this campaign is to bridge the design methods in the Rover/NERVA era, with a modern computational fluid dynamics and heat transfer methodology, to predict thermal, fluid, and hydrogen environments of a hypothetical solid-core, nuclear thermal engine the Small Engine, designed in the 1960s. The computational methodology is based on an unstructured-grid, pressure-based, all speeds, chemically reacting, computational fluid dynamics and heat transfer platform, while formulations of flow and heat transfer through porous and solid media were implemented to describe those of hydrogen flow channels inside the solid24 core. Design analyses of a single flow element and the entire solid-core thrust chamber of the Small Engine were performed and the results are presented herein

  11. The Influence Of The Hydraulic Exchange Relations In The Evolution Of Ice Jam Phenomena On Bistriţa River In The Area Between Dorna Arini (Suceava County And Borca (Neamţ County

    Directory of Open Access Journals (Sweden)

    Claudiu Gaman

    2015-10-01

    Full Text Available The presence on Bistriţa River, in identical climatic conditions, of sectors with well-developed ice formations in the immediate vicinity of river sectors lacking or with weakly developed such formations demonstrates the existence of other factors beside the meteorological and hydrological ones that may influence the evolution of freezing processes and implicitly of ice jams. A special role is held by the hydraulic exchange relations established between the river and the aquifers (Ciaglic, 1965; Ciaglic and Vornicu, 1973, the mentioned phenomena having a characteristic evolution, sometimes manifested through the total lack of ice due to underground input (Gaman, 2014. River alimentation from underground waters takes place in two situations: a nearby well-developed alluvial fans close to floodplain or terraces; b in areas where the river suddenly changes direction from flowing along one of the banks to an almost perpendicular position towards the valley, or where it meanders in the floodplain. The sectors of the river with areas of free water are those generating ice crystals and river-bottom ice and finally frazil slush. In the areas where the river loses water through infiltration in the floodplain, ice formations are much stronger according to the volume of water losses, and total freezing can be recorded. Field observations and measurements conducted in the winters of 2011-2012, 2012-2013, regarding the evolution of freeze phenomena, respectively ice jam formation, on Bistriţa River confirm the mentioned theory.

  12. Feedback from uncertainties propagation research projects conducted in different hydraulic fields: outcomes for engineering projects and nuclear safety assessment.

    Science.gov (United States)

    Bacchi, Vito; Duluc, Claire-Marie; Bertrand, Nathalie; Bardet, Lise

    2017-04-01

    In recent years, in the context of hydraulic risk assessment, much effort has been put into the development of sophisticated numerical model systems able reproducing surface flow field. These numerical models are based on a deterministic approach and the results are presented in terms of measurable quantities (water depths, flow velocities, etc…). However, the modelling of surface flows involves numerous uncertainties associated both to the numerical structure of the model, to the knowledge of the physical parameters which force the system and to the randomness inherent to natural phenomena. As a consequence, dealing with uncertainties can be a difficult task for both modelers and decision-makers [Ioss, 2011]. In the context of nuclear safety, IRSN assesses studies conducted by operators for different reference flood situations (local rain, small or large watershed flooding, sea levels, etc…), that are defined in the guide ASN N°13 [ASN, 2013]. The guide provides some recommendations to deal with uncertainties, by proposing a specific conservative approach to cover hydraulic modelling uncertainties. Depending of the situation, the influencing parameter might be the Strickler coefficient, levee behavior, simplified topographic assumptions, etc. Obviously, identifying the most influencing parameter and giving it a penalizing value is challenging and usually questionable. In this context, IRSN conducted cooperative (Compagnie Nationale du Rhone, I-CiTy laboratory of Polytech'Nice, Atomic Energy Commission, Bureau de Recherches Géologiques et Minières) research activities since 2011 in order to investigate feasibility and benefits of Uncertainties Analysis (UA) and Global Sensitivity Analysis (GSA) when applied to hydraulic modelling. A specific methodology was tested by using the computational environment Promethee, developed by IRSN, which allows carrying out uncertainties propagation study. This methodology was applied with various numerical models and in

  13. Idaho National Engineering Laboratory (INEL) technical review of YGN 3 and 4 thermal-hydraulic relative size effects

    Energy Technology Data Exchange (ETDEWEB)

    Ward, L.W.; Fineman, C.P.; Gruen, G.E.

    1989-08-01

    Combustion Engineering, Inc., (CE) and the Korean Advanced Energy Research Institute (KAERI) are jointly designing two 2825 MW{sub t} System 80 nuclear steam supply systems for construction in Korea. The two 2825 MW{sub t} plants are similar in design to the larger System 80 class of plants but are reduced in size from 3817 MW{sub t}. These plants will be operated by the Korean Electric Power Company and have been designated as Yonggwang Nuclear Units 3 and 4. The Idaho National Engineering Laboratory (INEL) was selected by CE to perform a third party independent technical review of the thermal-hydraulic safety analyses for Yonggwang Units 3 and 4. The purpose of the review is to establish the acceptability of the safety analyses addressing the differences in size between the 2825 and 3817 MW{sub t} CE designed System 80 plants. The analysis methods used by Combustion Engineering, Inc. were also reviewed to assure that only United States Nuclear Regulatory Commission approved methods were used for the Yonggwang Units 3 and 4 safety analyses and that the methods were applied in a manner consistent with that for the Palo Verde System 80 plants, currently in operation in the US. In general, it was found that the differences between 3817 and 2825 MW{sub t} units led to increased margins except for the large break LOCA (LBLOCA) and boron dilution transient. For the LBLOCA, use of improved models enhanced performance which allowed an increase in peak linear heat generation rate relative to that for the 3817 MW{sub t} plant. For the boron dilution event, an increase in the shutdown margin was necessary to assure the same time to criticality as that for the 3817 MW{sub t} plant. 39 refs., 9 figs., 4 tabs.

  14. Dynamically balanced, hydraulically driven compressor/pump apparatus for resonant free piston Stirling engines

    Science.gov (United States)

    Corey, John A.

    1984-05-29

    A compressor, pump, or alternator apparatus is designed for use with a resonant free piston Stirling engine so as to isolate apparatus fluid from the periodically pressurized working fluid of the Stirling engine. The apparatus housing has a first side closed by a power coupling flexible diaphragm (the engine working member) and a second side closed by a flexible diaphragm gas spring. A reciprocally movable piston is disposed in a transverse cylinder in the housing and moves substantially at right angles relative to the flexible diaphragms. An incompressible fluid fills the housing which is divided into two separate chambers by suitable ports. One chamber provides fluid coupling between the power diaphragm of the RFPSE and the piston and the second chamber provides fluid coupling between the gas spring diaphragm and the opposite side of the piston. The working members of a gas compressor, pump, or alternator are driven by the piston. Sealing and wearing parts of the apparatus are mounted at the external ends of the transverse cylinder in a double acting arrangement for accessibility. An annular counterweight is mounted externally of the reciprocally movable piston and is driven by incompressible fluid coupling in a direction opposite to the piston so as to damp out transverse vibrations.

  15. Effect of Compressibility on Contrail Ice Particle Growth in an Engine Jet

    Science.gov (United States)

    Garnier, François; Maglaras, Ephi; Morency, François; Vancassel, Xavier

    2014-06-01

    In order to understand the formation process of condensation trails (contrails), the flow in the near field of an aircraft engine jet is studied by using the three-dimensional Large Eddy Simulation technique. The configuration consists of a hot round jet laden with soot particles. The particles are tracked using the Lagrangian approach, and their growth is calculated by a microphysics water vapour deposition model. A series of simulations are performed at a realistic Reynolds number (Re = 3.2 · 106) for two different jet Mach numbers: quasi-incompressible jet flow (M = 0.2) and compressible jet flow (M = 1). Whatever the Mach number used the ice crystals first appear at the edges of the jet where the hot and moist flow mixes with the cold and dry ambient air. Both the thermal transfers and the mass coupling, which are more significant for the quasi-incompressible jet flow, control the growth process.

  16. Measurement of Sedimentary Interbed Hydraulic Properties and Their Hydrologic Influence near the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory

    Science.gov (United States)

    Perkins, Kim S.

    2003-01-01

    Disposal of wastewater to unlined infiltration ponds near the Idaho Nuclear Technology and Engineering Center (INTEC), formerly known as the Idaho Chemical Processing Plant, at the Idaho National Engineering and Environmental Laboratory (INEEL) has resulted in the formation of perched water bodies in the unsaturated zone (Cecil and others, 1991). The unsaturated zone at INEEL comprises numerous basalt flows interbedded with thinner layers of coarse- to fine-grained sediments and perched ground-water zones exist at various depths associated with massive basalts, basalt-flow contacts, sedimentary interbeds, and sediment-basalt contacts. Perched ground water is believed to result from large infiltration events such as seasonal flow in the Big Lost River and wastewater discharge to infiltration ponds. Evidence from a large-scale tracer experiment conducted in 1999 near the Radioactive Waste Management Complex (RWMC), approximately 13 km from the INTEC, indicates that rapid lateral flow of perched water in the unsaturated zone may be an important factor in contaminant transport at the INEEL (Nimmo and others, 2002b). Because sedimentary interbeds, and possibly baked-zone alterations at sediment-basalt contacts (Cecil and other, 1991) play an important role in the generation of perched water it is important to assess the hydraulic properties of these units.

  17. AutoCAD Civil 3D在水利工程中的应用%Application of AutoCAD Civil 3D in Hydraulic and hydroelectric Engineering

    Institute of Scientific and Technical Information of China (English)

    于佳

    2015-01-01

    The paper,taking the concrete arch dam which was built in XinJiang as an example ,introduced the application of Civil 3D in aspect of dam model of hydraulic engineering from generating original terrain sur-face,assembly setting of arch dam,dam crest circular arcs lofting,slope excavation,excavation and embank-ment volume engineering quantity calculation etc.its application prospects in hydraulic engineering was sum-marized,which can private reference for hydraulic and hydroelectric engineering designers.%以新疆某混凝土拱坝为例,从地形数据分析、地形曲面创建、定制拱坝体型装配、拱坝路线放样、边坡开挖、挖填方工程量统计等方面介绍了Civil 3D在水利工程中拱坝主体建模方面的应用。总结了AutoCAD Civil 3D在水利工程中的应用前景,可为水利水电工程设计者提供参考。

  18. Education for hydraulics and pneumatics in Kanazawa University, Department of Human and Mechanical System Engineering; Kanazawa Daigaku Ningen Kikai Kogakuka ni okeru yukuatsu kyoiku

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Y. [Kanazawa University, Ishikawa (Japan). Faculty of Engineering

    2000-03-15

    The above-named department was established in 1996. It advocates, standing on the basis of mechanical engineering, 'adaptation with man,' 'symbiosis with society,' and 'harmony with nature,' and, under these mottos, aims to bring up engineers who are able to create technologies in the field of mechanical engineering. There is no independent subject for fluid power. Relative subjects are the science of flows, thermodynamics and exercise, energy and environmental engineering, and nature and flow. Lectures are given using textbooks mainly. There is no subject that requires experiment on fluid power. It is hoped that teaching materials will be provided. Studies for graduation and master's theses are the 'suction performance of toroidal pumps' and the 'fluid force in, and flow coefficients of, spool valves.' Collaborative researches with industrial circles conducted so far involve the 'study of automotive vane pumps' and the 'suction performance of toroidal pumps.' It is difficult for subjects related to hydraulics and pneumatics to interest students greatly. To interest and attract students, it is felt, the concept like 'hydraulics and pneumatics signify power sources' which gives a tough and mighty impression should be replaced by a softer-tone expression like 'hydraulics/pneumatics and mechatronics and control.' (NEDO)

  19. Breadboard development of a hydraulically coupled free piston engine heat pump compressor

    Science.gov (United States)

    Marusak, T. J.

    1984-11-01

    The free piston Stirling engine (FPSE) was considered as a candidate for a thermally activated heat pump because of its potential for high efficiency coupled with long life and high reliability. The distinguishing features of the FPSE, one moving part and hermatic separation of the power cycle and refrigeration cycle working fluids, makes it ideally suited for a heat pump application. However, two major designs challenges have kept the FPSE in the realm of laboratory rather than product development. These challenges involve: effective control of a tuned resonant system over a wide range of loads and hermatic coupling of the driver and driven mechanical members.

  20. Hydraulic Arm Modeling via Matlab SimHydraulics

    OpenAIRE

    Věchet, Stanislav; Krejsa, Jiří

    2009-01-01

    System modeling is a vital tool for cost reduction and design process speed up in most engineering fields. The paper is focused on modeling of hydraulic arm as a part of intelligent prosthesis project, in the form of 2DOF open kinematic chain. The arm model combines mechanical, hydraulic and electric subsystems and uses Matlab as modeling tool. SimMechanics Matlab extension is used for mechanical part modeling, SimHydraulics toolbox is used for modeling of hydraulic circuit used for actuating...

  1. Designing educational software for analysing pressurised hydraulic systems in civil engineering

    Directory of Open Access Journals (Sweden)

    Myriam Rocío Pallares Muñoz

    2010-04-01

    Full Text Available New information technologies have opened up a world of inexhaustible possibilities in teaching. Using such technologies in technical teaching has become indispensable due to the nature of current resources in industrial design and production. This work consists of preparing didactic material (educational software aimed at tea- ching fluid mechanics, particularly analysing tube, tank and pumping systems, initially aimed at civil engineering students from the Universidad Santo Tomás in Bogotá. Such materials have been successfully developed and used in their formal programmes by several universities around the world during the last few years. The didactic software mentioned in this work was constructed using Visual Basic programming language. This has resulted in a very useful educational tool, leading to effective teacher—student communication which is suitable for both the classroom and students’ personal work (Angel y Bautista, 2001; Aguiar, 2002.

  2. Wind Tunnel Measured Effects on a Twin-Engine Short-Haul Transport Caused by Simulated Ice Accretions: Data Report

    Science.gov (United States)

    Reehorst, Andrew; Potapczuk, Mark; Ratvasky, Thomas

    1997-01-01

    The purpose of this report is to release the data from the NASA Langley/Lewis 14 by 22 foot wind tunnel test that examined icing effects on a 1/8 scale twin-engine short-haul jet transport model. Presented in this document are summary data from the major configurations tested. The entire test database in addition to ice shape and model measurements is available as a data supplement in CD-ROM form. Data measured and presented are: wing pressure distributions, model force and moment, and wing surface flow visualization.

  3. River Ice Data Instrumentation

    Science.gov (United States)

    1997-06-01

    edge in the field of ice engineering expands. For example, ice concentration and freezeup stage are not considered by the survey respondents to...im- pacts both freezeup and breakup jam formation Table 2. Ice parameters currently monitored, by Divisions (as of 1995). Ice parameters currently...V V V V Date of ice in V V V V Ice concentration V V V V Freezeup stage V V V V V Note: Southwestern Division does not currently monitor ice

  4. Reliability Analysis of Ice-Induced Fatigue and Damage in Offshore Engineering Structures

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    - In Bohai Gulf, offshore and other installations have collapsed by sea ice due to the fatigue and fracture of the main supporting components in the ice environments. In this paper presented are some results on fatigue reliability of these structures in the Gulf by investigating the distributions of ice parameters such as its floating direction and speed, sheet thickness, compressive strength, ice forces on the structures, and hot spot stress in the structure. The low temperature, ice breaking modes and component fatigue failure modes are also taken into account in the analysis of the fatigue reliability of the offshore structures experiencing both random ice loading and low temperatures. The results could be applied to the design and operation of offshore platforms in the Bohai Gulf.

  5. Simulation of how a geo-engineering intervention to restore arctic sea ice might work in practice

    Science.gov (United States)

    Forster, Piers; Jackson, Lawrence

    2014-05-01

    The declining trend in annual minimum Arctic sea ice coverage and years of more pronounced drops like 2007 and 2012 raise the prospect of an Arctic Ocean largely free of sea ice in late summer and the potential for a climate crisis or emergency. In a novel computer simulation, we treated one realisation of a climate model (HadGEM2) as the real world and tried to restore its Arctic sea ice by the rapid deployment of geo-engineering with emission of SO2 into the Arctic stratosphere. The objective was to restore the annual minimum Arctic sea ice coverage to levels seen in the late twentieth century using as little geo-engineering as possible. We took intervention decisions as one might do in the real world: by committee, using a limited set of uncertain "observations" from our simulated world and using models and control theory to plan the best intervention strategy for the coming year - so learning as we went and being thrown off course by future volcanoes and technological breakdowns. Uncertainties in real world observations were simulated by applying noise to emerging results from the climate model. Volcanic radiative forcing of twenty-first century climate was included with the timing and magnitude of the simulated eruptions unknown by the "geo-engineers" until after the year of the eruption. Monitoring of Arctic sea ice with the option to intervene with SO2 emissions started from 2018 and continued to 2075. Simulated SO2 emissions were made in January-May each year at a latitude of 79o N and an altitude within the range of contemporary tanker aircraft. The magnitude of emissions was chosen annually using a model predictive control process calibrated using results from CMIP5 models (excluding HadGEM2), using the simplified climate model MAGICC and assimilation of emerging annual results from the HadGEM2 "real world". We found that doubts in the minds of the "geo-engineers" of the radiative effect of their interventions, the side effects of their past interventions

  6. Development of property-transfer models for estimating the hydraulic properties of deep sediments at the Idaho National Engineering and Environmental Laboratory, Idaho

    Science.gov (United States)

    Winfield, Kari A.

    2005-01-01

    Because characterizing the unsaturated hydraulic properties of sediments over large areas or depths is costly and time consuming, development of models that predict these properties from more easily measured bulk-physical properties is desirable. At the Idaho National Engineering and Environmental Laboratory, the unsaturated zone is composed of thick basalt flow sequences interbedded with thinner sedimentary layers. Determining the unsaturated hydraulic properties of sedimentary layers is one step in understanding water flow and solute transport processes through this complex unsaturated system. Multiple linear regression was used to construct simple property-transfer models for estimating the water-retention curve and saturated hydraulic conductivity of deep sediments at the Idaho National Engineering and Environmental Laboratory. The regression models were developed from 109 core sample subsets with laboratory measurements of hydraulic and bulk-physical properties. The core samples were collected at depths of 9 to 175 meters at two facilities within the southwestern portion of the Idaho National Engineering and Environmental Laboratory-the Radioactive Waste Management Complex, and the Vadose Zone Research Park southwest of the Idaho Nuclear Technology and Engineering Center. Four regression models were developed using bulk-physical property measurements (bulk density, particle density, and particle size) as the potential explanatory variables. Three representations of the particle-size distribution were compared: (1) textural-class percentages (gravel, sand, silt, and clay), (2) geometric statistics (mean and standard deviation), and (3) graphical statistics (median and uniformity coefficient). The four response variables, estimated from linear combinations of the bulk-physical properties, included saturated hydraulic conductivity and three parameters that define the water-retention curve. For each core sample,values of each water-retention parameter were

  7. Design and Analysis of Hydraulic Chassis with Obstacle Avoidance Function

    Science.gov (United States)

    Hong, Yingjie; Zhang, Xiang

    2017-07-01

    This article mainly expounds the design of hydraulic system for the hydraulic chassis with obstacle avoidance function. Including the selection of hydraulic motor wheels, hydraulic pump, digital hydraulic cylinder and the matching of engine power. And briefly introduces the principle of obstacle avoidance.

  8. Hydraulics and pneumatics

    CERN Document Server

    Parr, Andrew

    2006-01-01

    Nearly all industrial processes require objects to be moved, manipulated or subjected to some sort of force. This is frequently accomplished by means of electrical equipment (such as motors or solenoids), or via devices driven by air (pneumatics) or liquids (hydraulics).This book has been written by a process control engineer as a guide to the operation of hydraulic and pneumatic systems for all engineers and technicians who wish to have an insight into the components and operation of such a system.This second edition has been fully updated to include all recent developments su

  9. Proceedings of the 18th International Conference on Engineering Design (ICED11)

    DEFF Research Database (Denmark)

    Maier, Anja; Mougaard, Krestine; Howard, Thomas J.

    The ICED series of conferences is the Design Society's "flagship" event. ICED11 took place on August 15-18, 2011, at the campus of the Danish Technical University in Lyngby/Copenhagen, Denmark. The Proceedings of the conference are published in 10 individual volumes, arranged according to topics........ All volumes of the Proceedings may be purchased individually through Amazon and other on-line booksellers. For members of the Design Society, all papers are available on this website. The Programme and Abstract Book is publically available for download.......The ICED series of conferences is the Design Society's "flagship" event. ICED11 took place on August 15-18, 2011, at the campus of the Danish Technical University in Lyngby/Copenhagen, Denmark. The Proceedings of the conference are published in 10 individual volumes, arranged according to topics...

  10. Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

    The paper presents research results using IT-Tools for CAD and dynamic modelling, simulation, analysis, and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. Matlab/Simulink and CATIA are used as IT-Tools. The contributions include results from on......-going research projects on fluid power and mechatronics based on tap water hydraulic servovalves and linear servo actuators and rotary vane actuators for motion control and power transmission. Development and design a novel water hydraulic rotary vane actuator for robot manipulators. Proposed mathematical...... modelling, control and simulation of a water hydraulic rotary vane actuator applied to power and control a two-links manipulator and evaluate performance. The results include engineering design and test of the proposed simulation models compared with IHA Tampere University’s presentation of research...

  11. Сomputational and experimental researches of ice pieces impact against a plate-imitator of a blade airfoil of an aircraft engine axial compressor

    Directory of Open Access Journals (Sweden)

    B. F. Shorr

    2014-01-01

    Full Text Available Ingestion of hailstones and shedding ice in operating aircraft engine can lead to damage of compressor rotating blades, as well as to change of gas-dynamic characteristics, and loss of engine thrust.The paper presents a computational and experimental study results of an ice impact against a thin edge of the steel plate, which simulates a compressor blade.Impacts of the ice bricks against the plate with a velocity corresponding to the circumference rate of blades rotation were realized by the pneumatic gunshots. The trials were carried out under various angles attack between the direction of the ice flight and the plate plane. The experiments has shown that on impact the ice brick is covered by numerous cracks and collapsed just at the very beginning of the interaction with a plate. Thus, a leading edge of the plate has a smoothly bending form without appearing cracks.For modeling the ice an isotropic elastoplastic material was chosen. Its failure was based on shear and rupture criteria. Two models of ice with different size of the yield point were used.The test results and their comparison with the numerical ones have shown the following: 1. Calculations of brick impact against a thin edge of the plate-imitator with accepted ice characteristics yield a correct qualitative picture of the plate damage, but lead to some undersizes of its leading edge bending.2. The ice design model with a larger yield point well reflects a character of the ice brick impact destruction as a formation of numerous cracks in it and splitting the piece into small particles, which was observed in the experiments. The model with smaller yield point shows the ice brick cutting into two parts without cracking.3. The plate damage considerably increases with increasing ice brick attack angle. Under a direct impact against the plate edge, the ice brick is cut into two halves, with no plastic deformations of the plate observed.4. Available results give the grounds to use

  12. Ice Crystal Icing Research at NASA

    Science.gov (United States)

    Flegel, Ashlie B.

    2017-01-01

    Ice crystals found at high altitude near convective clouds are known to cause jet engine power-loss events. These events occur due to ice crystals entering a propulsion systems core flowpath and accreting ice resulting in events such as uncommanded loss of thrust (rollback), engine stall, surge, and damage due to ice shedding. As part of a community with a growing need to understand the underlying physics of ice crystal icing, NASA has been performing experimental efforts aimed at providing datasets that can be used to generate models to predict the ice accretion inside current and future engine designs. Fundamental icing physics studies on particle impacts, accretion on a single airfoil, and ice accretions observed during a rollback event inside a full-scale engine in the Propulsion Systems Laboratory are summarized. Low fidelity code development using the results from the engine tests which identify key parameters for ice accretion risk and the development of high fidelity codes are described. These activities have been conducted internal to NASA and through collaboration efforts with industry, academia, and other government agencies. The details of the research activities and progress made to date in addressing ice crystal icing research challenges are discussed.

  13. Physical, Hydraulic, and Transport Properties of Sediments and Engineered Materials Associated with Hanford Immobilized Low-Activity Waste

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, Mark L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhang, Z. F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meyer, Philip D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thomle, Jonathan N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-02-28

    Current plans for treatment and disposal of immobilized low-activity waste (ILAW) from Hanford’s underground waste storage tanks include vitrification and storage of the glass waste form in a nearsurface disposal facility. This Integrated Disposal Facility (IDF) is located in the 200 East Area of the Hanford Central Plateau. Performance assessment (PA) of the IDF requires numerical modeling of subsurface flow and reactive transport processes over very long periods (thousands of years). The models used to predict facility performance require parameters describing various physical, hydraulic, and transport properties. This report provides updated estimates of physical, hydraulic, and transport properties and parameters for both near- and far-field materials, intended for use in future IDF PA modeling efforts. Previous work on physical and hydraulic property characterization for earlier IDF PA analyses is reviewed and summarized. For near-field materials, portions of this document and parameter estimates are taken from an earlier data package. For far-field materials, a critical review is provided of methodologies used in previous data packages. Alternative methods are described and associated parameters are provided.

  14. HYDRAULIC SERVO

    Science.gov (United States)

    Wiegand, D.E.

    1962-05-01

    A hydraulic servo is designed in which a small pressure difference produced at two orifices by an electrically operated flapper arm in a constantly flowing hydraulic loop is hydraulically amplified by two constant flow pumps, two additional orifices, and three unconnected ball pistons. Two of the pistons are of one size and operate against the additional orifices, and the third piston is of a different size and operates between and against the first two pistons. (AEC)

  15. Recovery of Exhaust Waste Heat for ICE Using the Beta Type Stirling Engine

    Directory of Open Access Journals (Sweden)

    Wail Aladayleh

    2015-01-01

    Full Text Available This paper investigates the potential of utilizing the exhaust waste heat using an integrated mechanical device with internal combustion engine for the automobiles to increase the fuel economy, the useful power, and the environment safety. One of the ways of utilizing waste heat is to use a Stirling engine. A Stirling engine requires only an external heat source as wasted heat for its operation. Because the exhaust gas temperature may reach 200 to 700°C, Stirling engine will work effectively. The indication work, real shaft power and specific fuel consumption for Stirling engine, and the exhaust power losses for IC engine are calculated. The study shows the availability and possibility of recovery of the waste heat from internal combustion engine using Stirling engine.

  16. Multi-elemental analysis of jet engine lubricating oils and hydraulic fluids and their implication in aircraft air quality incidents.

    Science.gov (United States)

    van Netten, C

    1999-05-07

    The flight crews of aircraft often report symptoms including dizziness, nausea, disorientation, blurred vision and tingling in legs and arms. Many of these incidents have been traced to contamination of cabin air with lubricating oil, as well as hydraulic fluid, constituents. Considering that these air contaminants are often subjected to temperatures in excess of 500 degrees C, a large number of different exposures can be expected. Although the reported symptoms are most consistent with exposures to volatile organic compounds, carbon monoxide, and the organophosphate constituents in these oils and fluids, the involvement of these agents has not been clearly demonstrated. Possible exposure to toxic elements, such as lead, mercury, thallium and others, have not been ruled out. In order to assess the potential of exposure to toxic elements a multi-elemental analysis was done on two hydraulic fluids and three lubricating oils which have been implicated in a number of air quality incidents. A secondary objective was to establish if the multi-elemental concentrations of the fluids tested are different enough to allow such an analysis to be used as a possible method of identifying the source of exposure that might have been present during aircraft air quality incidents. No significant concentrations of toxic elements were identified in any of the oils or hydraulic fluids. The elemental compositions of the samples were different enough to be used for identification purposes and the measurement of only three elements was able to achieve this. Whether these findings have an application, in aircraft air quality incident investigations, needs to be established with further studies.

  17. Employing numerical fluid mechanics in the development of hydraulic turbo-engines; Einsatz der numerischen Stroemungsmechanik in der Entwicklung hydraulischer Stroemungsmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Ruprecht, A.; Bauer, C.; Chihab, W.; Gentner, C.; Ginter, F.; Maihoefer, M.; Welzel, B.

    1994-12-31

    Numerical fluid mechanics as a method for the dimensioning and optimization of components of hydraulic turbo-engines is coming into prominence. In hydraulic systems, flows are almost exclusively turbulent with very high Reynolds` numbers. This is why Reynolds`-averaged Navier-Stokes equations are solved. Direct numerical solutions or coarse structure simulations are not possible as yet. In order to describe the turbulence, a turbulence model needs to be used. An optimum compromise between accuracy, general validity and computation effort for complex three-dimensional flows exists in the form of the k-{epsilon} model. To be sure, this model has some weak points (for instance, in the case of a strong streamline curvature), but on the whole it does provide satisfactory results. (orig./AKF) [Deutsch] Der Einsatz der numerischen Stroemungsmechanik zur Auslegung und Optimierung von Bauteilen hydraulischer Stroemungsmaschinen gewinnt stark an Bedeutung. In hydraulischen Anlagen liegen fast ausschliesslich turbulente Stroemungen bei sehr hohen Reynoldszahlen vor. Deshalb werden die Reynolds-gemittelte Navier-Stokesbleichungen geloest. Direkte numerische Loesungen oder Grobstruktursimulationen sind heute noch nicht moeglich. Zur Beschreibung der Turbulenz muss ein Turbulenzmodell verwendet werden. Einen optimalen Kompromiss zwischen Genauigkeit, Allgemeingueltigkeit und Rechenaufwand bei komplexen dreidimensionalen Stroemungen stellt das k-{epsilon} Modell dar. Zwar besitzt dieses Modell einige Schwachpunkte (z.B. bei starker Stromlinienkruemmung) es liefert aber i.a. doch befriedigende Ergebnisse. (orig./AKF)

  18. 工程机械液压传动系统常见故障的诊断与排除%Diagnosis and elimination in engineering machinery hydraulic system

    Institute of Scientific and Technical Information of China (English)

    李树胜

    2015-01-01

    只有对工程机械液压系统故障的发生规律进行了解与掌握,做好液压系统的维护管理工作,才能准确分析其故障产生原因,提高故障排除效率。本文主要针对工程机械液压传动系统常见故障的诊断与排除进行分析。%Only understand and masterthe occurrence rules of failure in engineering machinery hydraulic system, and managethe maintenance of hydraulic system, to accurately analyze the fault reason, and improve the efficiency of troubleshooting. The article mainly analyzed diagnosis and elimination of common failure in engineering machinery hydraulic system.

  19. Study on Hydraulic Engineering Cost Prediction by Unit Price Method%单价法预测水利工程造价的商榷

    Institute of Scientific and Technical Information of China (English)

    周峰; 岳春芳

    2011-01-01

    The infrastructure of water conservancy projects is one of the basic industries for the development of national economy. The hydraulic engineering is characterized by large scale,sophisticated technique, long duration,and big investment,which is a systematic and comprehensive work. The current method of cost prediction for water conservancy projects is the unit price method, which is still following the planned economy system. Although adjusted and improved several times, the unit price method still has many defects and the results are often inconsistent with the fact. The problems of calculating the hydraulic engineering cost in unit price predicting, such as labor budgeting and indirect expenditure, were analyzed and improving suggestions were proposed in this paper.%水利工程基本建设是我国国民经济发展的基础性产业之一,工程规模大,技术复杂,工期较长,投资很大,有很强的系统性和综合性.现行预测水利工程造价的单价法仍然沿用了计划经济体制时代模式,虽然经过了多次调整和改进,但还是存在诸多弊端,计算结果常常与实际偏差较大或与实际不符.现针对单价法预测水利工程造价中人工费、其他直接费、现场经费等计算中存在的问题进行分析,并提出了改进建议.

  20. Internal combustion engine report: Spark ignited ICE GenSet optimization and novel concept development

    Energy Technology Data Exchange (ETDEWEB)

    Keller, J.; Blarigan, P. Van [Sandia National Labs., Livermore, CA (United States)

    1998-08-01

    In this manuscript the authors report on two projects each of which the goal is to produce cost effective hydrogen utilization technologies. These projects are: (1) the development of an electrical generation system using a conventional four-stroke spark-ignited internal combustion engine generator combination (SI-GenSet) optimized for maximum efficiency and minimum emissions, and (2) the development of a novel internal combustion engine concept. The SI-GenSet will be optimized to run on either hydrogen or hydrogen-blends. The novel concept seeks to develop an engine that optimizes the Otto cycle in a free piston configuration while minimizing all emissions. To this end the authors are developing a rapid combustion homogeneous charge compression ignition (HCCI) engine using a linear alternator for both power take-off and engine control. Targeted applications include stationary electrical power generation, stationary shaft power generation, hybrid vehicles, and nearly any other application now being accomplished with internal combustion engines.

  1. Experimental investigation of hydraulic effects of two-stage fuel injection on fuel-injection systems and diesel combustion in a high-speed optical common-rail diesel engine

    OpenAIRE

    Herfatmanesh, MR; Zhao, H.

    2014-01-01

    In order to meet the ever more stringent emission standards, significant efforts have been devoted to the research and development of internal combustion engines. The requirements for more efficient and responsive diesel engines have led to the introduction and implementation of multiple injection strategies. However, the effects of such injection modes on the hydraulic systems, such as the high-pressure pipes and fuel injectors, must be thoroughly examined and compensated for since the combu...

  2. Light Aircraft Piston Engine Carburetor Ice Detector/Warning Device Sensitivity/Effectiveness.

    Science.gov (United States)

    1982-06-01

    2 RF5B 1 0 0 0 0 1 SA26 0 0 0 0 1 1 SCOOTER 0 0 1 0 0 1 SPORTS TERK 1 0 1 0 0 2 STITSSALLA 0 0 0 0 1 1 ST3KR 0 1 0 0 0 1 TC45B 0 0 1 0 0 1 UH12D 0 1 0...and the wdter solubility characteristics of tre fuel. hntrained water will freeze in cril fuel and tend to stay in suspension longer since the...specific gravity of ice is approximately the same as that of aviation gasoline. c. Water in suspension may freeze and form ice crystals of sufficient size

  3. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  4. 基于组合赋权-TOPSIS模型的水利工程建设方案优选决策方法%Hydraulic Engineering Construction Program Optimal Choice Based on Empowerment Combination TOPSIS Model

    Institute of Scientific and Technical Information of China (English)

    舒欢; 刘文娜

    2013-01-01

    对水利工程建设方案的选择是实现水资源高效开发与综合利用的关键环节,对社会的发展具有重大影响。针对水利工程建设的相应特点,构建水利工程建设方案的综合评价指标体系,运用层次分析法与熵权法来确定评价指标的组合权重,进而应用基于组合赋权的逼近理想解排序法对待选水利工程建设方案进行TOPSIS综合评价,计算出各方案的综合优越度,实现对水利建设工程方案的优选。并分别运用组合赋权、AHP法以及熵权法对某水利工程的7个备选方案进行逼近理想解排序,验证了基于组合赋权的TOPSIS法在水利工程建设方案优选决策过程中的适用性与优越性。%The choice of hydraulic engineering construction program is a key link to realize the efficient development and comprehensive utilization of water resources. It also plays a significant role in the development of our society. This paper constructs the evaluation index system in view of the related characteristics of hydraulic engineering project. Optimization of hydraulic engineering program is achieved by applying AHP and entropy to empowerment combination using the TOPSIS to evaluate the optimal methods,and calculating the synthetic superior degrees of every hydraulic engineering program. At last,taking the example of a hydraulic engineering project,methods of empowerment combination,AHP and entropy are used respectively to determine the weight and to evaluate the seven economic indexes of the hydraulic engineering program. It is verified that the empowerment combination TOPSIS model is applicable and superior in the process of hydraulic engineering construction program optimal choice decision.

  5. Engineering functional nanothin multilayers on food packaging: ice-nucleating polyethylene films.

    Science.gov (United States)

    Gezgin, Zafer; Lee, Tung-Ching; Huang, Qingrong

    2013-05-29

    Polyethylene is the most prevalent plastic and is commonly used as a packaging material. Despite its common use, there are not many studies on imparting functionalities to those films which can make them more desirable for frozen food packaging. Here, commercial low-density polyethylene (LDPE) films were oxidized by UV-ozone (UVO) treatment to obtain a negatively charged hydrophilic surface to allow fabrication of functional multilayers. An increase in hydrophilicity was observed when films were exposed to UVO for 4 min and longer. Thin multilayers were formed by dipping the UVO-treated films into biopolymer solutions, and extracellular ice nucleators (ECINs) were immobilized onto the film surface to form a functional top layer. Polyelectrolyte adsorption was studied and confirmed on silicon wafers by measuring the water contact angles of the layers and investigating the surface morphology via atomic force microscopy. An up to 4-5 °C increase in ice nucleation temperatures and an up to 10 min decrease in freezing times were observed with high-purity deionized water samples frozen in ECIN-coated LDPE films. Films retained their ice nucleation activity up to 50 freeze-thaw cycles. Our results demonstrate the potential of using ECIN-coated polymer films for frozen food application.

  6. Turbomachinery. Hydraulic and thermal turbo-engines and turbomachines. 5. rev. ed.; Stroemungsmaschinen. Hydraulische und thermische Kraft- und Arbeitsmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Menny, K.

    2006-07-01

    Turbomachines and turbo-engines use liquid and gaseous working fluids, i.e. they cover two different states of aggregation. Mechanical engineering, thermodynamics and gas dynamics as well as construction theory must all be considered in turbomachinery design. This is what the book intends to achieve with its conceptual structure. It starts by presenting the basic scientific equations and then proceeds to the specific engineering knowledge required in turbo-engine design and construction. The fifth edition was revised in several important aspects, i.e. the transition from bar to MPa and the thermodynamic state variables of water and steam according to IAPLWS 97. For this, many examples were newly calculated. The chapter on wind power systems has been brought up to date. Contents: Common fundamentals of turbomachinery; WAter turbines; Steam turbines and steam power systems; Gas turbines; Gyropumps; Blowers and compressors; Hydrodynamic transmissions and converters; Wind rotors and propellers; Appendix. (orig.)

  7. Study on hydraulics and transport in heterogeneous porous media (III). 1998 annual report of advanced engineering research

    Energy Technology Data Exchange (ETDEWEB)

    Jinno, K. [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering; Nakagawa, Tosao [Kyushu Univ., Fukuoka (Japan); Hosokawa, Kei [Kyushu Industrial Univ., Fukuoka (Japan); Hatanaka, K.; Ijiri, Yuji; Uchida, M. [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan); Watari, S. [CRC Research Inst. Inc., Tokyo (Japan); Kanazawa, Y. [IDC, Tokai, Ibaraki (Japan)

    1999-06-01

    In computerized simulation for nuclide migration in an underground disposal system of high-level radioactive wastes, one of the key parameters is macroscopic dispersion coefficients which is known to depend on local hydraulic parameters such as permeability. This study aims to clarify fundamental aspect of effective diffusive flows of contaminants in heterogeneously permeable media. A cooperative study between Kyushu University and JNC started in 1996, The report describes the validity of the present numerical calculation model for transport behaviors using laboratory data, the applicability of the present method to geological environments of heterogeneous porous media having different permeability, and the comparison of numerical results obtained using the present method with the results reported from the field test held at Horkheimer Insel, Germany, using tracer injection technique and measurements at several observation wells. (S. Ohno)

  8. Hydraulic Structures

    Data.gov (United States)

    Department of Homeland Security — This table is required whenever hydraulic structures are shown in the flood profile. It is also required if levees are shown on the FIRM, channels containing the...

  9. 46 CFR 112.50-3 - Hydraulic starting.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping... POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the following: (a) The hydraulic starting system must be...

  10. CRITICALITY CURVES FOR PLUTONIUM HYDRAULIC FLUID MIXTURES

    Energy Technology Data Exchange (ETDEWEB)

    WITTEKIND WD

    2007-10-03

    This Calculation Note performs and documents MCNP criticality calculations for plutonium (100% {sup 239}Pu) hydraulic fluid mixtures. Spherical geometry was used for these generalized criticality safety calculations and three geometries of neutron reflection are: {sm_bullet}bare, {sm_bullet}1 inch of hydraulic fluid, or {sm_bullet}12 inches of hydraulic fluid. This document shows the critical volume and critical mass for various concentrations of plutonium in hydraulic fluid. Between 1 and 2 gallons of hydraulic fluid were discovered in the bottom of HA-23S. This HA-23S hydraulic fluid was reported by engineering to be Fyrquel 220. The hydraulic fluid in GLovebox HA-23S is Fyrquel 220 which contains phosphorus. Critical spherical geometry in air is calculated with 0 in., 1 in., or 12 inches hydraulic fluid reflection.

  11. 14 CFR 33.72 - Hydraulic actuating systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic actuating systems. 33.72 Section... AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.72 Hydraulic actuating systems. Each hydraulic actuating system must function properly under all conditions in which...

  12. Innovative Control Effectors (ICE)

    Science.gov (United States)

    1996-01-01

    including weight, maneuver performance, signa- ture, hydraulic requirements, demands on the flight control system (FCS) design, and car - rier (CV...applicable to the car - rier-based configurations. Figure 7-36 summarizes an assessment of the ICE series 101 configuration control allocation evaluation. ICE...plain leading edge flaps, all moving horizontal tails, rudder, two airbrakes under fuselage F-15C inner trailing edge plain flap, outer aileron, all

  13. Ice Harbor Spillway Dissolved Gas Field Studies: Before and After Spillway Deflectors

    Science.gov (United States)

    2016-07-01

    1000 Under Program Number U425243, “Dissolved Gas Abatement Study” Monitored by U.S. Army Engineer District, Walla Walla 201 N 3rd Ave Walla...201 N 3rd Ave Walla Walla, WA 99362 10. SPONSOR/MONITOR’S ACRONYM(S) NWW 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION...Dissolved oxygen Hydraulic structures Spillways Stilling basins Water--Air entrainment Tailwater ecology Ice Harbor Dam

  14. Influence of environmental parameters and of their interactions on the release of metal(loid)s from a construction material in hydraulic engineering.

    Science.gov (United States)

    Schmukat, A; Duester, L; Goryunova, E; Ecker, D; Heininger, P; Ternes, T A

    2016-03-05

    Besides the leaching behaviour of a construction material under standardised test-specific conditions with laboratory water, for some construction materials it is advisable to test their environmental behaviour also under close to end use conditions. The envisaged end use combined with the product characteristics (e.g. mineral phases) is decisive for the choice of environmental factors that may change the release of substance that potentially cause adverse environmental effects (e.g. fertilisation or ecotoxicity). At the moment an experimental link is missing between mono-factorial standardised test systems and non standardised complex incubation experiments such as mesocosms which are closer to environmental conditions. Multi-factorial batch experiments may have the potential to close the gap. To verify this, batch experiments with copper slag were performed which is used as armour stones in hydraulic engineering. Design of experiments (DoE) was applied to evaluate the impact of pH, ionic strength, temperature and sediment content on the release of As, Cu, Mo, Ni, Pb, Sb and Zn. The study shows that release and sediment-eluent partitioning of metal(loid)s are impacted by interactions between the studied factors. Under the prevalent test conditions sediment acts as a sink enhancing most strongly the release of elements from the material.

  15. An ice-templated, linearly aligned chitosan-alginate scaffold for neural tissue engineering.

    Science.gov (United States)

    Francis, Nicola L; Hunger, Philipp M; Donius, Amalie E; Riblett, Benjamin W; Zavaliangos, Antonios; Wegst, Ulrike G K; Wheatley, Margaret A

    2013-12-01

    Several strategies have been investigated to enhance axonal regeneration after spinal cord injury, however, the resulting growth can be random and disorganized. Bioengineered scaffolds provide a physical substrate for guidance of regenerating axons towards their targets, and can be produced by freeze casting. This technique involves the controlled directional solidification of an aqueous solution or suspension, resulting in a linearly aligned porous structure caused by ice templating. In this study, freeze casting was used to fabricate porous chitosan-alginate (C/A) scaffolds with longitudinally oriented channels. Chick dorsal root ganglia explants adhered to and extended neurites through the scaffold in parallel alignment with the channel direction. Surface adsorption of a polycation and laminin promoted significantly longer neurite growth than the uncoated scaffold (poly-L-ornithine + Laminin = 793.2 ± 187.2 μm; poly-L-lysine + Laminin = 768.7 ± 241.2 μm; uncoated scaffold = 22.52 ± 50.14 μm) (P < 0.001). The elastic modulus of the hydrated scaffold was determined to be 5.08 ± 0.61 kPa, comparable to reported spinal cord values. The present data suggested that this C/A scaffold is a promising candidate for use as a nerve guidance scaffold, because of its ability to support neuronal attachment and the linearly aligned growth of DRG neurites.

  16. The Applications of Dry Jet Mixing in the Coastal Areas of Hydraulic Engineering%粉喷桩在沿海地区水利工程中的的应用

    Institute of Scientific and Technical Information of China (English)

    戴恩运

    2013-01-01

      在沿海地区水利工程中,水泥粉喷搅拌桩是地基与基础处理常用的一种方法。本文通过作者的工作实践,并结合工程实例对粉喷桩在沿海地区水利工程中的应用进行简单的阐述与分析。%In the coastal areas of hydraulic engineering, the c-ement powder jet mixing pile is a common method of the sub-grade and the basis of processing. In this article, the author ba-ses on the working practices, briefly elaborates and analysis th-e applications of Dry Jet Mixing in the coastal areas of hydrau-lic engineering.

  17. 基于典型工况的装载机发动机与液力变矩器匹配%Power matching on loader engine and hydraulic torque converter based on typical operating conditions

    Institute of Scientific and Technical Information of China (English)

    徐礼超; 侯学明

    2015-01-01

    In order to avoid the deficiencies of obtaining net engine torque in several common methods, and realize more scientific and reasonable matching between engine and hydraulic torque converter, a hydraulic test system for wheel loader was established, the performances of three sensors were calibrated, and a quantitative relationship was obtained between outlet pressure of hydraulic pump and engine torque consumed by the pump. Some actual tests were performed under typical operating conditions, and the test data were processed by a series of procedures, including segmentation, mergence, filtration, elimination of abnormal value and weighted average calculation with nSoft software, and the engine torque actually consumed by loader hydraulic system was obtained when comprehensively considering operation materials and their corresponding proportions, then a matching scheme between engine and hydraulic torque converter was put forward based on typical operating conditions. According to the original feature data of the tested loader engine, the deducted empiric values of engine torque for full power matching and partial power matching, and the actual engine torque value consumed by loader hydraulic system, three kinds of different characteristic curves of net engine torque were obtained by using a data fitting method. After fitting the original feature data of tested loader hydraulic torque converter, according to the characteristic curves of hydraulic torque converter between efficiency, torque coefficient, moment coefficient and rotational speed ratio, the corresponding torque coefficient, moment coefficient and rotational speed ratio were obtained when the torque converter efficiency was the highest;and according to the matching principle of engine with torque converter and load calculation formula of torque converter, the corresponding torque converter diameters of matching schemes for full power, experimental power and partial power were calculated. On the basis of

  18. 液压系统在工程机械传动中的应用和优势%On Application of Hydraulic System in Transmission of Engineering Mechanery and its Advantages

    Institute of Scientific and Technical Information of China (English)

    凌健

    2015-01-01

    The hydraulic system ,which takes hydraulic oi as the transmission medium,is a way to transfer power and energy , it has been widely used in various industries, such as the engineering machinery, metallurgy, agricultural machinery, automobile, petroleum ,machine tool and so on.. It greatly improves the work efficiency of construction machinery and energy efficiency in engineering machinery, it also achieve the smooth transmission of engineering mechanical power . This paper mainly introduced the characteristics, the principle and the developing tendency of the hydraulic system.%液压系统是以液压油作为传递介质,进行动力和能量传递的形式,在工程机械、冶金、农机、汽车、石油和机床等行业中得到了广泛的应用。液压系统在工程机械上的应用极大地提高了工程机械的工作效率和能源利用率,实现了工程机械动力的平稳传动。文章主要介绍了液压系统在工程机械中应用的特点、原理和未来的发展趋势。

  19. Geo synthetics in hydraulic and coastal engineering: Filters, revetments and sand filled structures; Geosinteticos en ingenieria hidraulica y costera: filtros, revestimientos y estructuras llenas de arena

    Energy Technology Data Exchange (ETDEWEB)

    Bezuijen, A.; Pilarczyk, K. W.

    2014-02-01

    The paper deals with 2 applications of geo textiles in coastal and hydraulic engineering: Geo textiles in filters and revetments; and geo textiles in sand filled structure. Geo textiles are often replacing granular filters. However, they have different properties than a granular filter. For the application of geo textiles in revetments, the consequences of the different properties will be shown: how permeability is influenced by a geo textile and what can be the consequences of the weight differences between granular and geo textile filters. In the other application, the filter properties of geo textiles are only secondary. In geo textile tubes and containers the geo textile is used as wrapping material to create large unties that will not erode during wave attach. the structures with geo textile tubes and containers serve as an alternative for rock based structures. The first of these structures were more or less constructed by trial and error, but research on the shape of the structures, the stability under wave attach and the durability of the used of the used material has given the possibility to use design tools for these structures. Recently also the morphological aspects of these structures have been investigated. This is of importance because regularly structures with geo textile tubes fail due to insufficient toe protection against the scour hole that that develops in front of the structure, leading to undermining of the structure. Recent research in the Dealt Flume of Deltares and the Large Wave Flume in Hannover has led to better understanding what mechanisms determine the stability under wave attach. It is shown that also the degree of filling is of importance and the position of the water level with respect to the tube has a large influence. (Author)

  20. Influence of environmental parameters and of their interactions on the release of metal(loid)s from a construction material in hydraulic engineering

    Energy Technology Data Exchange (ETDEWEB)

    Schmukat, A., E-mail: schmukat@harzwasserwerke.de [Harzwasserwerke GmbH, Zur Granetalsperre 8, 38685 Langelsheim (Germany); Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany); Duester, L. [Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany); Goryunova, E. [Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany); KAPP-Chemie GmbH & Co. KG, Industriestr. 2-4, 56357 Miehlen (Germany); Ecker, D.; Heininger, P.; Ternes, T.A. [Federal Institute of Hydrology, Department of Aquatic Chemistry, Am Mainzer Tor 1, 56068 Koblenz (Germany)

    2016-03-05

    Highlights: • DoE supported multi-factorial study on the metal(loid) release from copper slag. • Interactions of four parameters were studied and weighted. • An effective separation method between slag and sediment was established. • The metal(loid) partitioning between sediment, slag and eluent is described. • The knowledge on the potential environmental impact of copper slag is increased. - Abstract: Besides the leaching behaviour of a construction material under standardised test-specific conditions with laboratory water, for some construction materials it is advisable to test their environmental behaviour also under close to end use conditions. The envisaged end use combined with the product characteristics (e.g. mineral phases) is decisive for the choice of environmental factors that may change the release of substance that potentially cause adverse environmental effects (e.g. fertilisation or ecotoxicity). At the moment an experimental link is missing between mono-factorial standardised test systems and non standardised complex incubation experiments such as mesocosms which are closer to environmental conditions. Multi-factorial batch experiments may have the potential to close the gap. To verify this, batch experiments with copper slag were performed which is used as armour stones in hydraulic engineering. Design of experiments (DoE) was applied to evaluate the impact of pH, ionic strength, temperature and sediment content on the release of As, Cu, Mo, Ni, Pb, Sb and Zn. The study shows that release and sediment-eluent partitioning of metal(loid)s are impacted by interactions between the studied factors. Under the prevalent test conditions sediment acts as a sink enhancing most strongly the release of elements from the material.

  1. 发动机齿轮室盖液压自动夹具设计%Design of Hydraulic Automated Fixture for Gear Housing Cover of Engine

    Institute of Scientific and Technical Information of China (English)

    孙燕华; 唐立平; 李薇

    2011-01-01

    齿轮室盖零件是典型的形状复杂、加工部位众多、形位精度要求高的铝合金薄壁箱壳类零件,其数控加工工艺及工装设计是复杂薄壁箱壳类零件数控加工的典型案例.通过对某型号发动机齿轮室盖零件结构与尺寸精度要求的分析,编制符合企业加工能力和要求的数控加工工艺路线.针对薄壁装夹刚性差、加工部位多与走刀路径干涉问题,合理选择装夹点位置,布置浮动支撑,设计相应液压自动夹具.该套数控加工工艺及工装已应用于实践,为其他同类型零件加工提供借鉴.%The gear housing cover is a typical aluminum alloy thin-walled shell box part, which is complex, numerous machining locations and high precision demand. The design of NC machining process and fixture for gear housing cover of engine is a typical case of the NC machining for complex thin-walled shell box part. Based on analyzing structure and dimension accuracy requirements of the gear housing cover part in a certain engine, the NC process route which accorded with processing capacity and requirement of enterprises was worked out. Aiming at the problems such as poor clamping rigidity of thin-walled shell part, numerous machining locations and tool path interference, the hydraulic automated fixture was designed by reasonable selection of clamping points and floating type support cylinders. The NC machining process and fixture has been applied to practice. It can provide good reference for other same type parts.

  2. Analysis of an Artificial Tailplane Icing Flight Test of a High-Wing, Twin-Engine Aircraft

    Science.gov (United States)

    Shaikh, Shehzad M.

    The US Air Force Flight Test Center (AFFTC) conducted a civilian, Federal Aviation Administration (FAA) sponsored, evaluation of tailplane icing of a twin-turboprop business transport at Edwards Air Force Base. The flight test was conducted to evaluate ice shape growth and extent of ice on the tailplane for specific weather conditions of Liquid Water Content (LWC), droplet size, and ambient temperature. This work analyzes the flight test data comparing the drag for various tailplane icing conditions with respect to a flight test verified calibrated aircraft model. Although less than a third of the test aircraft was involved in the icing environment, the results of this analysis shows a significant increase in the aircraft drag with respect to the LWC, droplet size, and ambient temperature.

  3. Discussion on the Making Standardization of Network Schedule Plan in Hydraulic Engineering%工程项目中网络进度计划编制标准化研究

    Institute of Scientific and Technical Information of China (English)

    王仁超; 郝伟峰

    2012-01-01

    Since most of the current project management software only offer functions of network schedule plan calculation, analysis, optimization, control, and so on, but have not provided the function of auxiliary making. This causes different engineering staffs making different Network Schedule Plans which are also very difficult to evaluate. Based on the characteristics of Hydraulic Engineering, this paper discusses the connotation sense of standardization of making network schedule plan in Hydraulic Engineering, and studies on the secondary development of P3 software and its coupling with a Network Schedule Plan software-Network to explores a making standardized path of Hydraulic Engineering network schedule plan. Finally, this coupling system is verified as feasible through the actual construction schedule.%由于目前大多数网络进度计划软件仅提供了网络进度计划的计算、分析、优化、控制等功能,而没有提供辅助编制功能.造成不同工程人员编制出的网络计划差异很大,且对编制的网络进度计划的可行性评价较难.探讨了工程项目中网络进度计划编制标准化的内涵,并就P3(Primavera Project Planner)软件二次开发以及该软件与一个网络计划软件-Network耦合问题进行了研究,探索了工程网络进度计划编制标准化的一条路径.最后以实际工程的施工进度计划对该耦合系统进行验证.

  4. 23 CFR 650.111 - Location hydraulic studies.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Location hydraulic studies. 650.111 Section 650.111 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  5. ICE SLURRY APPLICATIONS.

    Science.gov (United States)

    Kauffeld, M; Wang, M J; Goldstein, V; Kasza, K E

    2010-12-01

    The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology.

  6. 缸间齿轮联动液压发动机结构设计与研究%Structure design and research of the gear-linked cylinders hydraulic engine

    Institute of Scientific and Technical Information of China (English)

    舒培; 张洪信; 肖汝琴; 孙文革

    2015-01-01

    针对液压自由活塞发动机和液压约束活塞发动机在关键技术和产业化方面出现的问题,创新性地提出了缸间齿轮联动液压发动机的结构原理,在此基础上对作为影响缸间齿轮联动液压发动机整机性能关键部件的缸间齿轮齿条传动机构和液压配流系统进行了结构设计与研究。缸间齿轮齿条传动机构采用正变位直齿圆柱齿轮和标准齿条无侧隙啮合传动,通过合理选择几何参数和强度校核,其能够支持发动机正常稳定运转;设计了一种往复柱塞泵用转套式配流系统,能够实现单向吸油和泵油,完成动力输出,且容积效率高、结构紧凑,相较于传统阀配流往复柱塞泵配流结构优势明显。缸间齿轮联动液压发动机的结构设计与研究为随后的整机性能研究、仿真优化和样机试制提供了参考依据。%The structure and working principle of the Gear-linked Cylinders Hydraulic Engine ( GCHE) is put forward creatively for the issues appearing in the critical technologies and industrialization of the Hydraulic Free Piston Engine ( HFPE) and the Hydraulic Confined Piston Engine ( HCPE) .And a structure researching design of the rack and pinion mechanism between cylin-ders and the hydraulically orifice system which play important roles in the engine performance has been conducted on the basis . The rack and pinion mechanism takes the method of positive displacement spur gear and standard rack no backlash meshing .With the geometric parameters selected and the strength check done reasonably ,the mechanism is able to support normal and stable op-eration of the engine.Meanwhile,a rotating sleeve type hydraulically orifice system for reciprocating piston pump is designed ,it can implement unidirectional suction and pump oil to complete the power output with high volumetric efficiency and compact structure and has obvious advantages compared to traditional valve type orifice

  7. Hydraulic Actuators with Autonomous Hydraulic Supply for the Mainline Aircrafts

    Directory of Open Access Journals (Sweden)

    I. S. Shumilov

    2014-01-01

    Full Text Available Applied in the aircraft control systems, hydraulic servo actuators with autonomous hydraulic supply, so-called, hydraulic actuators of integrated configuration, i.e. combination of a source of hydraulic power and its load in the single unit, are aimed at increasing control system reliability both owing to elimination of the pipelines connecting the actuator to the hydraulic supply source, and owing to avoidance of influence of other loads failure on the actuator operability. Their purpose is also to raise control system survivability by eliminating the long pipeline communications and their replacing for the electro-conductive power supply system, thus reducing the vulnerability of systems. The main reason for a delayed application of the hydraulic actuators in the cutting-edge aircrafts was that such aircrafts require hydraulic actuators of considerably higher power with considerable heat releases, which caused an unacceptable overheat of the hydraulic actuators. Positive and negative sides of the hydraulic actuators, their alternative options of increased reliability and survivability, local hydraulic systems as an advanced alternative to independent hydraulic actuators are considered.Now to use hydraulic actuators in mainline aircrafts is inexpedient since there are the unfairly large number of the problems reducing, first and last, safety of flights, with no essential weight and operational advantages. Still works to create competitive hydraulic actuators ought to be continued.Application of local hydraulic systems (LHS will allow us to reduce length of pressure head and drain pipelines and mass of pipelines, as well as to raise their general fail-safety and survivability. Application of the LHS principle will allow us to use a majority of steering drive advantages. It is necessary to allocate especially the following:- ease of meeting requirements for the non-local spread of the engine weight;- essentially reducing length and weight of

  8. Hydraulic fracturing chemicals and fluids technology

    CERN Document Server

    Fink, Johannes

    2013-01-01

    When classifying fracturing fluids and their additives, it is important that production, operation, and completion engineers understand which chemical should be utilized in different well environments. A user's guide to the many chemicals and chemical additives used in hydraulic fracturing operations, Hydraulic Fracturing Chemicals and Fluids Technology provides an easy-to-use manual to create fluid formulations that will meet project-specific needs while protecting the environment and the life of the well. Fink creates a concise and comprehensive reference that enables the engineer to logically select and use the appropriate chemicals on any hydraulic fracturing job. The first book devoted entirely to hydraulic fracturing chemicals, Fink eliminates the guesswork so the engineer can select the best chemicals needed on the job while providing the best protection for the well, workers and environment. Pinpoints the specific compounds used in any given fracturing operation Provides a systematic approach to class...

  9. Engineering geological characteristics and the hydraulic fracture propagation mechanism of the sand-shale interbedded formation in the Xu5 reservoir

    Science.gov (United States)

    Lu, Cong; Li, Mei; Guo, Jian-Chun; Tang, Xu-Hai; Zhu, Hai-Yan; Yong-Hui, Wang; Liang, Hao

    2015-06-01

    In the Xu5 formation the sandstone reservoir and the shale reservoir are interbedded with each other. The average thickness of each formation is about 8 m, which increases the difficulty of the hydraulic fracturing treatment. The shale thickness ratio (the ratio of shale thickness to formation thickness) is 55-62.5%. The reservoir is characterized by ultra-low porosity and permeability. The brittleness index of sandstone is 0.5-0.8, and the brittleness index of shale is 0.3-0.8. Natural fractures are poorly developed and are mainly horizontal and at a low angle. The formation strength is medium and the reservoir is of the hybrid strike-slip fault and reverse fault stress regime. The difference between the minimum principal stress and the vertical stress is small, and the maximum horizontal principal stress is 20 MPa higher than the minimum horizontal principal stress and vertical stress. A mechanical model of a hydraulic fracture encountering natural fractures is built according to geological characteristics. Fracture mechanics theory is then used to establish a hydraulic fracturing model coupling the seepage-stress-damage model to simulate the initiation and propagation of a fracture. The hydraulic fracture geometry is mainly I-shaped and T-shaped, horizontal propagation dominates the extension, and vertical propagation is limited. There is a two to three meter stress diversion area around a single hydraulic fracture. The stress diversion between a hydraulic fracture and a natural fracture is advantageous in forming a complex fracture. The research results can provide theoretical guidance for tight reservoir fracturing design.

  10. EFFECTS OF RIVER ICE ON STAGE——DISCHARGE RELATIONSHIPS

    Institute of Scientific and Technical Information of China (English)

    Jueyi SUI; Ronald THRING; Bryan W. KARNEY; Jun WANG

    2007-01-01

    Using field observations at four gauging stations along the Inner Mongolia Reach of the Yellow River in China, this paper explores effects of the ice on the hydraulics of this river reach for four different conditions, namely: under open channel flow, during ice-running period, the ice-covered period, and the river break-up period. The rating curves were found to be well recognized under open channel situations, but were sometimes poorly defined and extremely variable under ice conditions. The results also show that the water level is insensitive to flowing ice prior to freeze-up. However, significant, but hardly surprising, variations were observed during ice-covered conditions. The rating curves for both the ice covered condition and river ice breakup period are developed and some related hydraulic issues are examined. Additionally, the impacts of the ice accumulation and associated riverbed deformation during ice period on the rating curves are discussed.

  11. Dynamic characteristics analysis of hydraulic pipes in fully hydraulic steering system of engineering vehicles%工程车辆全液压转向系统管路特性分析

    Institute of Scientific and Technical Information of China (English)

    葛振亮; 侯友山; 姜勇

    2011-01-01

    基于功率键合图理论建立了工程车辆全液压转向系统的数学模型.运用20sim键图软件重点研究了全液压转向系统管路的动态特性以及液压管路参数对转向系统动态特性的影响.研究结果表明:对于小管径及长管路转向系统,管路内液阻、液感较大,有利于抑制系统的高频振荡和冲击以增强转向系统的稳定性,但延长了系统的动态响应时间;对于大管径及短管路转向系统,管路液阻、液感较小,系统动态响应较快,但转向系统振荡剧烈,振荡幅度增大,振荡次数增多,不利于车辆的操作稳定性.提高油液的体积弹性模量利于改善系统的动态响应速度和稳定性.研究结果为全液压转向系统的设计及管网动态特性分析提供理论依据.%Based on power bond graph diagram method, the general mathematical model of fully hydraulic steering system(FHSS) was established. The dynamic characteristics of hydraulic pipes of FHSS and the influences of pipeline parameters on the steering system were mainly analyzed by using 20sim bond graph software. The study results show that for the long and small diameter pipeline steering systems, the fluid resistance and fluid sense get larger, which are conducive to suppress high-frequency oscillation and shock to enhance the stability of steering system, but prolong the system's dynamic response time; for the short and large diameter pipeline, the fluid resistance and fluid sense get smaller,the system responses rapidly, but the steering system endures intensive high-frequency oscillation, with the increasing of both amplitude and frequency, which is uncondueive to the stability of steering system. Increasing the volume elastic modulus of oil in the system can improve the dynamic response speed and stability. The study results provide a theoretical support for the design of fully hydraulic steering system and for the analysis of pipeline nets' dynamic characteristics.

  12. Level-Ice Melt Ponds in the Los Alamos Sea Ice Model, CICE

    Science.gov (United States)

    2012-12-06

    physical features such as snow topography and hydraulic meltwater transport rates both laterally and vertically. Departing from the cellular automaton...parameterizations before, or are mod- eled here in a different manner from prior work. When meltwater forms with snow still on the ice, the water is...thickest ice, near Greenland and the Canadian Arctic. A larger fraction of this thicker sea ice is ridged, less level ice is available for ponding, and

  13. Dam-Site Selection of Huayuan Reservoir Hydraulic Engineering Complex in Longjiang County%花园水库枢纽工程坝址选择

    Institute of Scientific and Technical Information of China (English)

    付彦

    2011-01-01

    In accordance with Planning for 100 Billion jin Grain Production Capability Construction in Heilongjiang Province compiled in 2008,Comprehensive Planning of Songhua River Watershed compiled in April,2010,Brief Introduction of Important Projects in Heilongjiang Province Water Conservancy Development "Twelve Five-year Plans" Planning compiled in July,2010 and Planning for Construction of 10 Million mu Paddy Fields Added Newly in Heilongjiang Province compiled in 2010,the Huayuan Reservoir was recommended as the important hydraulic engineering complex in the comprehensive regulation of Yalu River watershed in the near term.The total storage of Huayuan Reservoir is 0.372 billion m3 and irrigation area is 0.1313 million hm2.The curves of cost and submerge loss were used to estimate the project costs and investment for submerge compensation for the two dam sites located on the river section in light of the same task of flood control and irrigation.The cost of upper dam site is 311.23million Yuan more than the lower dam site,meanwhile,there exists the problems of partial submerged lands in Inner Mongolia,it is difficult to cooperate the submerge compensation problems over the different provinces,and the lower dam site will be selected at the stage of project proposal.%根据2008年编制的《黑龙江省千亿斤粮食生产能力建设规划》、2010年4月编制的《松花江流域综合规划》、2010年7月编制的《黑龙江省水利发展"十二五"规划重点工程项目简介》以及2010年编制的《黑龙江省新增1000万亩水田建设规划》,花园水库均被推荐为近期雅鲁河流域综合治理的重点枢纽工程。花园水库总库容3.72亿m3,灌溉面积13.13万hm2,在河段内两坝址按相同的防洪、灌溉任务,按造价曲线和淹没损失曲线估算工程造价和淹没补偿投资,上坝址比下坝址多31123万元,且存在淹没内蒙部分土地的问题,跨省区协调淹没赔偿问题难度大,项目建议书阶段选定下坝址。

  14. Concrete ice abrasion rig and wear measurements

    NARCIS (Netherlands)

    Shamsutdinova, G.; Rike, P.B.; Hendriks, M.A.N.; Jacobsen, S.

    2015-01-01

    The wear of concrete material due to ice movement is a challenge for offshore and coastal structures. Concrete surfaces exposed to moving ice are subjected to wear at various rates depending on concrete and ice properties. At NTNU, Department of Structural Engineering, concrete ice abrasion phenomen

  15. Salmon River Ice Jam Control Studies

    Science.gov (United States)

    1990-04-01

    Deadrnan low stream depths often allows ice to pass beneath the Anchor /boom. But during freezeup , when the quantity of frazil ice is large, an ice...report. US Army Engineer District, Walla LITERATURE CITED Walla. Zufelt, J.E. (1987) Salmon River ice control study, Axelson, K.D. (1990) Freezeup

  16. Concrete ice abrasion rig and wear measurements

    NARCIS (Netherlands)

    Shamsutdinova, G.; Rike, P.B.; Hendriks, M.A.N.; Jacobsen, S.

    2015-01-01

    The wear of concrete material due to ice movement is a challenge for offshore and coastal structures. Concrete surfaces exposed to moving ice are subjected to wear at various rates depending on concrete and ice properties. At NTNU, Department of Structural Engineering, concrete ice abrasion phenomen

  17. Applied hydraulic transients

    CERN Document Server

    Chaudhry, M Hanif

    2014-01-01

    This book covers hydraulic transients in a comprehensive and systematic manner from introduction to advanced level and presents various methods of analysis for computer solution. The field of application of the book is very broad and diverse and covers areas such as hydroelectric projects, pumped storage schemes, water-supply systems, cooling-water systems, oil pipelines and industrial piping systems. Strong emphasis is given to practical applications, including several case studies, problems of applied nature, and design criteria. This will help design engineers and introduce students to real-life projects. This book also: ·         Presents modern methods of analysis suitable for computer analysis, such as the method of characteristics, explicit and implicit finite-difference methods and matrix methods ·         Includes case studies of actual projects ·         Provides extensive and complete treatment of governed hydraulic turbines ·         Presents design charts, desi...

  18. Hydraulic energy storage for hydrostatic travel drives; Hydraulischer Energiespeicher fuer hydrostatische Fahrantriebe

    Energy Technology Data Exchange (ETDEWEB)

    Renz, Klaus [Bosch Rexroth AG, Elchingen (Germany). Anwendungstechnik Strassenbaumaschinen und Raupenfahrzeuge; Vogl, Karl-Heinz [Bosch Rexroth AG, Elchingen (Germany). Anwendungstechnik, Technischer Vertrieb; Brand, Michael [Bosch Rexroth AG, Elchingen (Germany). Anwendungsentwicklung Arbeitsmaschinen

    2010-09-15

    with their Hydraulic Fly Wheel (HFW) Bosch Rexroth has developed a new concept for hydrostatic travel drives which addresses the changed characteristics of the newest engine generation. As a consequence of the Tier 4 final regulations engines will soon exhibit more sluggish load assumption behaviour - the hydraulic fly wheel compensates for this and assists the hydrostatic travel drive or implement hydraulics. (orig.)

  19. Human impacts on river ice regime in the Carpathian Basin

    Science.gov (United States)

    Takács, Katalin; Nagy, Balázs; Kern, Zoltán

    2014-05-01

    . Climate change and river ice regime research should also take into account these anthropogenic impacts. Reference: Ashton, W.D. 1986. River and lake ice engineering. Water Resources Publication, USA 485 p. Starosolszky, Ö., 1990. Effect of river barrages on ice regime. Journal of Hydraulic Research 28/6, 711-718. Williams, G.P., 1970. A note on the break-up of lakes and rivers as indicators of climate change. Atmosphere 8 (1), 23-24.

  20. Ice Sheets & Ice Cores

    DEFF Research Database (Denmark)

    Mikkelsen, Troels Bøgeholm

    Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known...... as Dansgaard-Oeschger (DO) events would add to our knowledge of the climatic system and – hopefully – enable better forecasts. Likewise, to forecast possible future sea level rise it is crucial to correctly model the large ice sheets on Greenland and Antarctica. This project is divided into two parts...

  1. RIDES: Raman Icing Detection System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Inflight icing of engines and airframe presents a significant hazard to air transport, especially at lower flight elevations during take-off or on approach. Ice...

  2. Lobster Tail Ice Formation on Aerosurface

    Science.gov (United States)

    1999-01-01

    Glace Ice formation commonly refered to as 'Lobster Tail' by scientists and engineers, is caused to form on the leading edge of a aircraft tail section in the icing research tunnel at the NASA Glenn Research Center, Cleveland, Ohio.

  3. HYDRAULICS, LOUISA COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydraulic analysis for estimating flood stages for a flood insurance study. It...

  4. Hydraulic Hybrid Vehicles

    Science.gov (United States)

    EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

  5. Integrated hydraulic cooler and return rail in camless cylinder head

    Energy Technology Data Exchange (ETDEWEB)

    Marriott, Craig D [Clawson, MI; Neal, Timothy L [Ortonville, MI; Swain, Jeff L [Flushing, MI; Raimao, Miguel A [Colorado Springs, CO

    2011-12-13

    An engine assembly may include a cylinder head defining an engine coolant reservoir, a pressurized fluid supply, a valve actuation assembly, and a hydraulic fluid reservoir. The valve actuation assembly may be in fluid communication with the pressurized fluid supply and may include a valve member displaceable by a force applied by the pressurized fluid supply. The hydraulic fluid reservoir may be in fluid communication with the valve actuation assembly and in a heat exchange relation to the engine coolant reservoir.

  6. Possibilities of utilization of fly ash from the black coal Power Engineering of the U. S. Steel Košice

    Directory of Open Access Journals (Sweden)

    Františka Michalíková

    2005-11-01

    Full Text Available The paper presents modes of a direct utilization of the fly ash by-product of the combustion of black power coal in the slag - bottom boilers of the Division Plant Power Engineering ( DP PE of the U. S. Steel Košice ( next USSK . The properties of fly ash limit its use in metallurgy and foundry industry. The fly ash is directly utilizable in the metallurgical industry as a component of powder cover mixtures and insulation inserts, heat insulation parts and exothermical mixtures. The most important components in the mixtures are light micro spheres – cenospheres and heavy micro spheres – plerospheres. The micro spheres significantly improve properties of the powder cover mixtures.

  7. Design of a laboratory hydraulic device for testing of hydraulic pumps

    Directory of Open Access Journals (Sweden)

    Pavel Máchal

    2013-01-01

    Full Text Available The present contribution deals with solves problem of research of testing device to monitor of hydrostatic pumps durability about dynamic loading under laboratory conditions. When carrying out the design of testing device are based on load characteristics of tractor hydraulic circuit, the individual characteristics of hydraulic components and performed calculations. Load characteristics on the tractors CASE IH Magnum 310, JOHN DEERE 8100, ZETOR FORTERRA 114 41 and Fendt 926 Vario were measured. Design of a hydraulic laboratory device is based on the need for testing new types of hydraulic pumps or various types of hydraulic fluids. When creating of hydraulic device we focused on testing hydraulic pumps used in agricultural and forestry tractors. Proportional pressure control valve is an active member of the hydraulic device, which provides change of a continuous control signal into relative pressure of operating fluid. The advantage of a designed hydraulic system is possibility of simulation of dynamic operating loading, which is obtained by measurement under real conditions, and thereby creates laboratory conditions as close to real conditions as possible. The laboratory device is constructed at the Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra.

  8. Ice Jams, Winter 1996-1997

    Science.gov (United States)

    1998-06-01

    Engineers® Rivers, streams, and lakes in cold regions freeze during winter months. Ice jams may form during initial ice cover formation ( freezeup jams) or...when ice cover breaks up (breakup jams). Both freezeup and breakup jams cause backwater flooding and damage to low-lying areas and municipal...Laboratory (CRREL) Ice Jam Database is a compilation of freezeup and breakup ice jam events in the United States (White 1996). Currently, there are more

  9. Alternating current breakdown voltage of ice electret

    Science.gov (United States)

    Oshika, Y.; Tsuchiya, Y.; Okumura, T.; Muramoto, Y.

    2017-09-01

    Ice has low environmental impact. Our research objectives are to study the availability of ice as a dielectric insulating material at cryogenic temperatures. We focus on ferroelectric ice (iceXI) at cryogenic temperatures. The properties of iceXI, including its formation, are not clear. We attempted to obtain the polarized ice that was similar to iceXI under the applied voltage and cooling to 77 K. The polarized ice have a wide range of engineering applications as electronic materials at cryogenic temperatures. This polarized ice is called ice electret. The structural difference between ice electret and normal ice is only the positions of protons. The effects of the proton arrangement on the breakdown voltage of ice electret were shown because electrical properties are influenced by the structure of ice. We observed an alternating current (ac) breakdown voltage of ice electret and normal ice at 77 K. The mean and minimum ac breakdown voltage values of ice electret were higher than those of normal ice. We considered that the electrically weak part of the normal ice was improved by applied a direct electric field.

  10. A New Unusual Ice-induced Sedimentary Structure: the Silt Mushroom.

    Science.gov (United States)

    Jianhua, Zhong; Liangtian, Ni; Ningliang, Sun; Chuang, Liu; Bing, Hao; Mengchun, Cao; Xin, Chen; Ke, Luo; Shengxin, Liu; Leitong, Huang; Guanqun, Yang; Shaojie, Wang; Feifei, Su; Xuejing, He; Yanqiu, Xue

    2016-11-11

    Upon channel bars or point bars within the lows of the Yellow River, a new sedimentary structure, named 'silt mushroom', has been observed. The process of their formation is interpreted to be via the ice process. The name, the silt mushroom comes from their figurative form. This is because they look somewhat similar to mushroom's in size and shape; being in the range of 1 to 10 cm in diameter, with the medium 3-5 cm, and on average 10 cm in height, occuring generally in groups, and occasionally in isolation in relatively soft silt. They develop in the transition from winter to spring, and are convincingly related to ice processes. Ice-induced silt mushrooms are best examined in association with the many other newly discovered ice-induced sedimentary structures (over 20 kinds). Clearly, up to now, ice processes have been significantly underestimated. With the substantial discovery of the ice-induced silt mushroom, it opens up new questions. This is because its structure mirrors the same sedimentary structures found in rocks, questioning their genesis, and sedimentary environment analysis. This achievement is significant not only in sedimentology, but also in palaeogeography, palaeoclimate, geological engineering, hydraulics and fluviology.

  11. M1078 Hybrid Hydraulic Vehicle Fuel Economy Evaluation

    Science.gov (United States)

    2012-09-01

    PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 28-09-2012 2. REPORT TYPE Interim Report 3. DATES COVERED (From...system shakedown and developmental testing. During developmental testing, a hydraulic motor failure occurred. Although not catastrophic, the motor...main hydraulic hybrid system control module to request the TCM to shift the transmission. Clutch Operation with engine- off (hydraulic-only power) or

  12. 匹配发动机的液压泵复合式控制特性研究%Study on Combined Control for Matching Hydraulic Pumps to Engine

    Institute of Scientific and Technical Information of China (English)

    黄新磊; 胡军科; 陈鹤梅; 罗宁

    2011-01-01

    研究液压系统优化控制问题,针对工程机械的复杂工况经常使得液压泵与发动机扭矩匹配不合理,造成发动机熄火或功率利用过低.为提高系统性能,提出了DA(排量转速控制)与EP(电比例控制)的复合式控制方案,调节泵排量使其扭矩与发动机外特性相适应.建立流量连续方程和力平衡方程复合式控制微分形式的数学模型,并导出其传递函数.在MATLAB/Simulink平台搭建模型,对控制特性进行了仿真研究.结果表明,复合式控制可使液压泵与发动机高效匹配,为发动机的液压系统优化控制提供了科学依据.%Complex working conditions in construction machinery result in the torque mismatch between hydraulic pumps and the engine, which probably leads to engine stalling or poor power utilizing. The control scheme combined EP with DA has been proposed against this, thus pumps' placement is regulated to cope with the engine' s external characteristic. After demonstrating principles of the displacement varying, this paper builds up the dynamic math-ematic model of the combined control in differential form, which deduces the system's block diagram in transfer function. Therefore, the control scheme's simulation is able to be carried out with MATLAB/Simulink. Results of the simulation manifest that the combined control can make hydraulic pumps and engines match well and has effect on pushing construction machinery forwards to high performance of energy saving and reliability.

  13. ON THE THEORIES OF HYDRAULIC GEOMETRY

    Institute of Scientific and Technical Information of China (English)

    Vijay P. SINGH

    2003-01-01

    Hydraulic geometry is of fundamental importance in planning, design, and management of river engineering and training works. Although some concepts of hydraulic geometry were proposed toward the end of the nineteenth century, the real impetus toward formulating a theory of hydraulic geometry was provided by the work of Leopold and Maddock (1953). A number of theories have since been proposed.Some of the theories are interrelated but others are based on quite different principles. All theories,however, assume that the river flow is steady and uniform and the river tends to attain a state of equilibrium or quasi-equilibrium. The differences are due to the differences in hydraulic mechanisms that the theories employ to explain the attainment of equilibrium by the river.

  14. Numerical simulation of mechanical breakup of river ice-cover

    Institute of Scientific and Technical Information of China (English)

    WANG Jun; HE Liang; CHEN Pang-pang; SUI Jueyi

    2013-01-01

    Ice jams and ice dams in rivers will cause significant rises of water levels.Under extreme conditions,the ice flooding during winter or early spring may occur.In this paper,by considering the fluid-solid coupling effect caused by the water and the ice cover,the mechanisms of the mechanical breakup of the river ice cover are studied.A formula is obtained for determining whether or not the mechanical breakup process would happen under the hydraulic pressure of the flow.Combined with the hydraulic model under the ice covered flow,a numerical model is built and the interaction between the discharge,the hydraulic pressure under the ice cover and the date for the mechanical breakup of the river ice cover is simulated.The simulated results of the dates for the mechanical breakup of the river ice cover agree very well with the field observations of the breakups of the river ice cover in the Hequ Reach of the Yellow River.Therefore,the numerical model might serve as a good preliminary step in studying the breakup of the river ice-cover,evidencing many important parameters that affect the ice-cover process.

  15. Hydraulic conductivity of a firn aquifer system in southeast Greenland

    Science.gov (United States)

    Miller, Olivia L.; Solomon, D. Kip; Miège, Clément; Koenig, Lora S.; Forster, Richard R.; Montgomery, Lynn N.; Schmerr, Nicholas; Ligtenberg, Stefan R. M.; Legchenko, Anatoly; Brucker, Ludovic

    2017-05-01

    Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between 10-30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5x10-5 and 1.1x10-3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7x10-4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method) and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

  16. Hydraulic Conductivity of a Firn Aquifer in Southeast Greenland

    Directory of Open Access Journals (Sweden)

    Olivia L. Miller

    2017-05-01

    Full Text Available Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between ~10 and 30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5 × 10−5 and 1.1 × 10−3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7 × 10−4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

  17. Engineering Encounters: Designing Healthy Ice Pops. A STEM Enrichment Project for Second Graders Incorporates Nutrition and Design Principles

    Science.gov (United States)

    Bubnick, Laura; Enneking, Katie; Egbers, Julie

    2016-01-01

    Science, technology, engineering, and math (STEM) education piques students' innate curiosity and opens their eyes to hundreds of career possibilities. This column presents ideas and techniques to enhance your science teaching. This month's issue shares information about a STEM enrichment project for second graders that incorporates nutrition and…

  18. Hydraulic Evaluation of Marmet Lock Filling and Emptying System, Kanawha River, West Virginia

    Science.gov (United States)

    2015-04-01

    Army Engineer Waterways Experiment Station. Headquarters, U.S. Army Corps of Engineers. 1975. Hydraulic design of lock culvert valves . Engineer Manual ...operations with various valve operations was computed. The numerical model results indicate that the hydraulic conditions are not significantly...2 1.3 Vertical-Lift Valves

  19. Electro-hydraulic variable valve system for hybrid pneumatic-internal combustion engine%气动-内燃混合动力系统的电液可变气门研究

    Institute of Scientific and Technical Information of China (English)

    叶锦; 李道飞; 王雷; 徐焕祥; 俞小莉

    2013-01-01

    针对气动-内燃混合动力在不同工作模式下顺利切换的关键问题,开展了电液驱动全可变气门开发研究.介绍了气动-内燃混合动力的不同工作模式,基于热力循环,分析了3种关键工作模式下的可变气门控制策略.以低速工况下混合动力系统气动模式为例,设计开发了无复位弹簧电液全可变气门原型样机,利用高速开关电磁阀控制可变气门液压油路通断,并基于NI-CompactRIO平台开发了可变气门控制系统,最后对电液气门进行了初步的试验分析.研究结果表明,电液全可变气门存在一定的响应延时,通过控制进油时间和保持时间,可以实现气门升程和正时的调整,满足气动模式常用转速范围工作要求.%In order to switch among multiple working modes of the concept hybrid engine,including air motor mode,supercharged combustion mode and regenerative braking mode,an electro-hydraulic variable valve system was designed and manufactured.Based on a newly designed prototype,the intake and exhaust valving strategies in different modes were analyzed.The on/off of hydraulic line was controlled with high speed electromagnetic valves.By using NI-CompactRIO platform,the control system hardware and software of valve prototype were designed and optimized.Finally,preliminary tests of the variable valve were conducted.The results indicate that,though there is some dynamic delay of valve lift,by regulating the opening and duration of electromagnetic valves,the optimal lift and timing strategy of the engine valve can be achieved for the air motor mode of the hybrid engine concept.

  20. Dependence of Segregation Potential on the Thermal and Hydraulic Conditions Predicted by Model M1

    Science.gov (United States)

    1994-04-01

    of Segregation Potential on the Thermal and Hydraulic Conditions Predicted by Model M, Yoshisuke Nakano April 1994 Rom edfor OFFICE OF THE CHIEF OF...function where i = 1, 2, 3 final ice lens k thermal conductivity of a frozen fringe 7* temperature at n, at the phase equilib- k ...hermalcoductivityoftheunfrozenpart rium of water of the soil T; average temperature gradient in R1 k , thermal conductivity of an ice layer U defined by eq 29a K0 hydraulic

  1. Turbulent heat transfer as a control of platelet ice growth in supercooled under-ice ocean boundary layers

    Science.gov (United States)

    McPhee, Miles G.; Stevens, Craig L.; Smith, Inga J.; Robinson, Natalie J.

    2016-04-01

    Late winter measurements of turbulent quantities in tidally modulated flow under land-fast sea ice near the Erebus Glacier Tongue, McMurdo Sound, Antarctica, identified processes that influence growth at the interface of an ice surface in contact with supercooled seawater. The data show that turbulent heat exchange at the ocean-ice boundary is characterized by the product of friction velocity and (negative) water temperature departure from freezing, analogous to similar results for moderate melting rates in seawater above freezing. Platelet ice growth appears to increase the hydraulic roughness (drag) of fast ice compared with undeformed fast ice without platelets. Platelet growth in supercooled water under thick ice appears to be rate-limited by turbulent heat transfer and that this is a significant factor to be considered in mass transfer at the underside of ice shelves and sea ice in the vicinity of ice shelves.

  2. Design of a hydraulic bending machine

    Science.gov (United States)

    Steven G. Hankel; Marshall Begel

    2004-01-01

    To keep pace with customer demands while phasing out old and unserviceable test equipment, the staff of the Engineering Mechanics Laboratory (EML) at the USDA Forest Service, Forest Products Laboratory, designed and assembled a hydraulic bending test machine. The EML built this machine to test dimension lumber, nominal 2 in. thick and up to 12 in. deep, at spans up to...

  3. Power management in hydraulically actuated mobile equipment

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2008-01-01

    The focus of the current paper is on the control of hydraulic systems when utilizing the advances that electronic control may bring with regard to power management, prioritized flow sharing and anti-stall, arising from being able to control both pump, valves and engine electronically. A simple mo...

  4. Main Problems and Countermeasures in Hydraulic Engineering Design Estimates Preparation%水利工程设计概算编制中的主要问题及对策

    Institute of Scientific and Technical Information of China (English)

    冯家团

    2013-01-01

      水利工程概算编制是工程设计的重要组成部分,对于合理确定工程造价预算、确保有效控制工程项目投资规模、合理使用投资、提高投资回报率,是必不可少的。本文简要归纳了一些普遍存在于水利工程设计概算编制中的问题,并结合工程实际提出了几项应对措施,以期提升设计概算编制的质量、保证项目投资控制目标的实现,从而取得较好的投资效益和社会效益。%Preparation of hydraulic engineering budget estimates is an important part of engineering design .It is essential for reasonably determining project cost budgets , ensuring effective control of the project investment scale , rationally using investment, and improving the return rate on investment .This paper briefly summarizes some problems prevalent in the budget water conservancy project design budget estimates .Engineering practice is combined to device counter-measures in order to improve the quality of the design estimates preparation and ensure the realization of project investment control goals, thereby obtaining better investment benefits and social benefits .

  5. Ice slurry cooling research: Storage tank ice agglomeration and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K. [Argonne National Lab., IL (United States); Hayashi, Kanetoshi [NKK Corp., Kawasaki (Japan)

    1999-08-01

    A new facility has been built to conduct research and development on important issues related to implementing ice slurry cooling technology. Ongoing studies are generating important information on the factors that influence ice particle agglomeration in ice slurry storage tanks. The studies are also addressing the development of methods to minimize and monitor agglomeration and improve the efficiency and controllability of tank extraction of slurry for distribution to cooling loads. These engineering issues impede the utilization of the ice slurry cooling concept that has been under development by various groups.

  6. Optimal design for cone valve of mechanical-hydraulic dual power engine%机械-液压双元动力发动机锥形配流阀的优化

    Institute of Scientific and Technical Information of China (English)

    霍炜; 张纪鹏; 张洪信; 张铁柱

    2013-01-01

    机械-液压双元动力输出发动机(MHPE)将传统的内燃机和柱塞泵融为一体,可同时或单独输出机械、液压2种动力。MHPE采用锥形阀配流系统,其容积效率高低直接影响MHPE的整机性能。该文以容积效率为目标函数,以锥形阀的工作条件和结构尺寸为约束条件,以MHPE锥形阀的结构参数为优化变量,建立了优化模型,并基于iSIGHT软件进行优化设计。优化结果表明,优化后系统的容积效率提高5.71%,改善程度较大。%Heat energy can be converted to hydraulic energy by a traditional engine-pump system(EPS). However, the EPS has some disadvantages, such as a long transmission line, low efficiency, and a complex and heavy structure. With an integrating traditional internal combustion engine and plunger pump to remove intermediate links, a mechanical-hydraulic dual power engine (MHPE) can convert heat energy to hydraulic energy directly. Therefore, the energy conversion efficiency was improved and the structure was simplified. MHPE can output one of or both machinery and hydraulic powers, and it can be used for excavators, loaders, bulldozers, and other engineering machineries. The distribution valve, the important element of MHPE, can affect the volume efficiency of the system directly by its structure and performance. The 36114ZG4B type six-cylinders radial MHPE was developed. A-H20L type one-way cone valve with the valve disk of 0.07557 kg quality, 0.028 m large diameter, 0.021 m small diameter and 40° angle is used as an inlet valve. A DIF-L20H type one-way cone valve with the valve disk of 0.04672 kg quality, 0.021 m large diameter, 0.016 m small diameter and 45° angle was used as an outlet valve. With the volume efficiency taken as an objective function, the cone valve’s working conditions and structure dimensions taken as constraint conditions, and the cone valve’s structure parameters taken as optimization variables, an optimization model

  7. 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

  8. Proceedings of ICED'09

    DEFF Research Database (Denmark)

    The 17th International Conference on Engineering Design, ICED'09, was held August 24-27 2009 at Stanford University, California, USA. The Conference is the flagship event of the Design Society, a society dedicated to contributing to a broad and established understanding of development and design....

  9. Climatic change and river ice breakup

    Energy Technology Data Exchange (ETDEWEB)

    Beltaos, S. [Environment Canada, National Water Research Institute, Burlington, ON (Canada); Burrell, B. C. [New Brunswick Dept. of the Environment and Local Government, Sciences and Planning Division, Fredericton, NB (Canada)

    2003-07-01

    An overview of climatic factors and impact relative to river ice engineering and science is presented. An explanation of the fundamentals of climatic change is followed by a review of direct and indirect climatic influences that govern river ice breakup and related trends. Known responses of river ice to climatic change and potential future changes to ice breakup processes are described along with the probable ecological and socio-economic consequences of these changes. Changes in engineering approaches to accommodate the present ice regime and predicted changes in climatic variables that affect river ice processes and reduce the vulnerability of infrastructure and ecosystems to climatic change are examined. Future research on the links between river ice and stream ecology is suggested to identify ecological concerns that may result from changes in river ice regimes induced by climatic change. 60 refs., 3 figs.

  10. Ice Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, atmospheric trace gases, and other aspects of climate and environment derived from ice cores drilled on glaciers and ice...

  11. Education of mining engineers with the specialization in Rescue, fire and safety technique at the BERG Faculty of the Technical University of Košice

    Directory of Open Access Journals (Sweden)

    Sedlatý Václav

    2002-12-01

    Full Text Available After the separation of Czechoslovakia, in 1993, the Mining Faculty (now BERG Faculty of the Technical University of Košice started a teaching program with the specialization in mining rescue, fire guard and safety technique at the Detachment in Prievidza, because of all the needs and conditions related to the education of engineers in the mentioned areas. During the last 10 years, the Detachment in Prievidza has been growing in terms of number of students. From the beginning of this period to present days 75 students graduated. The full-time studies last five years and the academic years are divided into two semesters of 15 weeks each. The semesters are finished by examination sessions. The first 2 years, in principle, include basic studies in mathematics, scientific subjects and some subjects related to earth sciences. The third and fourth year are generally devoted to basic technical subjects of mining and underground works, and then to rescue, fire and safety subjects. A practical work experience has to be gained by students in a mine or fire and safety stations. The practical training term is scheduled after the third academic year. During the last two semesters the students are preparing their Master’s degree thesis using a stay in the mine company or other firms to receive the necessary information and data.

  12. Ice cores

    DEFF Research Database (Denmark)

    Svensson, Anders

    2014-01-01

    Ice cores from Antarctica, from Greenland, and from a number of smaller glaciers around the world yield a wealth of information on past climates and environments. Ice cores offer unique records on past temperatures, atmospheric composition (including greenhouse gases), volcanism, solar activity......, dustiness, and biomass burning, among others. In Antarctica, ice cores extend back more than 800,000 years before present (Jouzel et al. 2007), whereas. Greenland ice cores cover the last 130,000 years...

  13. Ice cores

    DEFF Research Database (Denmark)

    Svensson, Anders

    2014-01-01

    Ice cores from Antarctica, from Greenland, and from a number of smaller glaciers around the world yield a wealth of information on past climates and environments. Ice cores offer unique records on past temperatures, atmospheric composition (including greenhouse gases), volcanism, solar activity......, dustiness, and biomass burning, among others. In Antarctica, ice cores extend back more than 800,000 years before present (Jouzel et al. 2007), whereas. Greenland ice cores cover the last 130,000 years...

  14. Vibration of hydraulic machinery

    CERN Document Server

    Wu, Yulin; Liu, Shuhong; Dou, Hua-Shu; Qian, Zhongdong

    2013-01-01

    Vibration of Hydraulic Machinery deals with the vibration problem which has significant influence on the safety and reliable operation of hydraulic machinery. It provides new achievements and the latest developments in these areas, even in the basic areas of this subject. The present book covers the fundamentals of mechanical vibration and rotordynamics as well as their main numerical models and analysis methods for the vibration prediction. The mechanical and hydraulic excitations to the vibration are analyzed, and the pressure fluctuations induced by the unsteady turbulent flow is predicted in order to obtain the unsteady loads. This book also discusses the loads, constraint conditions and the elastic and damping characters of the mechanical system, the structure dynamic analysis, the rotor dynamic analysis and the system instability of hydraulic machines, including the illustration of monitoring system for the instability and the vibration in hydraulic units. All the problems are necessary for vibration pr...

  15. Ice crystal ingestion by turbofans

    Science.gov (United States)

    Rios Pabon, Manuel A.

    This Thesis will present the problem of inflight icing in general and inflight icing caused by the ingestion of high altitude ice crystals produced by high energy mesoscale convective complexes in particular, and propose a new device to prevent it based on dielectric barrier discharge plasma. Inflight icing is known to be the cause of 583 air accidents and more than 800 deaths in more than a decade. The new ice crystal ingestion problem has caused more than 100 flights to lose engine power since the 1990's, and the NTSB identified it as one of the causes of the Air France flight 447 accident in 1-Jun2008. The mechanics of inflight icing not caused by ice crystals are well established. Aircraft surfaces exposed to supercooled liquid water droplets will accrete ice in direct proportion of the droplet catch and the freezing heat transfer process. The multiphase flow droplet catch is predicted by the simple sum of forces on each spherical droplet and a droplet trajectory calculation based on Lagrangian or Eulerian analysis. The most widely used freezing heat transfer model for inflight icing caused by supercooled droplets was established by Messinger. Several computer programs implement these analytical models to predict inflight icing, with LEWICE being based on Lagrangian analysis and FENSAP being based on Eulerian analysis as the best representatives among them. This Thesis presents the multiphase fluid mechanics particular to ice crystals, and explains how it differs from the established droplet multiphase flow, and the obstacles in implementing the former in computational analysis. A new modification of the Messinger thermal model is proposed to account for ice accretion produced by ice crystal impingement. Because there exist no computational and experimental ways to fully replicate ice crystal inflight icing, and because existing ice protections systems consume vast amounts of energy, a new ice protection device based on dielectric barrier discharge plasma is

  16. Ice Cream

    NARCIS (Netherlands)

    Scholten, E.

    2014-01-01

    Ice cream is a popular dessert, which owes its sensorial properties (mouth feel) to its complex microstructure. The microstructure is a result of the combination of the ingredients and the production process. Ice cream is produced by simultaneous freezing and shearing of the ice cream mix, which

  17. Ice Cream

    NARCIS (Netherlands)

    Scholten, E.

    2014-01-01

    Ice cream is a popular dessert, which owes its sensorial properties (mouth feel) to its complex microstructure. The microstructure is a result of the combination of the ingredients and the production process. Ice cream is produced by simultaneous freezing and shearing of the ice cream mix, which res

  18. Computational engineering

    CERN Document Server

    2014-01-01

    The book presents state-of-the-art works in computational engineering. Focus is on mathematical modeling, numerical simulation, experimental validation and visualization in engineering sciences. In particular, the following topics are presented: constitutive models and their implementation into finite element codes, numerical models in nonlinear elasto-dynamics including seismic excitations, multiphase models in structural engineering and multiscale models of materials systems, sensitivity and reliability analysis of engineering structures, the application of scientific computing in urban water management and hydraulic engineering, and the application of genetic algorithms for the registration of laser scanner point clouds.

  19. Thermal-hydraulic analysis of nuclear reactors

    CERN Document Server

    Zohuri, Bahman

    2015-01-01

    This text covers the fundamentals of thermodynamics required to understand electrical power generation systems and the application of these principles to nuclear reactor power plant systems. It is not a traditional general thermodynamics text, per se, but a practical thermodynamics volume intended to explain the fundamentals and apply them to the challenges facing actual nuclear power plants systems, where thermal hydraulics comes to play.  Written in a lucid, straight-forward style while retaining scientific rigor, the content is accessible to upper division undergraduate students and aimed at practicing engineers in nuclear power facilities and engineering scientists and technicians in industry, academic research groups, and national laboratories. The book is also a valuable resource for students and faculty in various engineering programs concerned with nuclear reactors. This book also: Provides extensive coverage of thermal hydraulics with thermodynamics in nuclear reactors, beginning with fundamental ...

  20. 免校正扩充现实技术在水利工程建设中的应用%Applications of Uncalibrated Augmented Reality to Hydraulic Engineering Construction

    Institute of Scientific and Technical Information of China (English)

    申杰; 刘浩吾

    2001-01-01

    扩充现实技术使观察者能够同时看到真实世界以及扩充了真实世界的、来自于计算机模型的信息。首次提出了扩充现实技术在水利工程中的应用,讨论了基于仿射不变量的扩充现实及它的研究方法和应用背景,实现了虚拟物体与现实图像的融合。%Augmented reality(AR) is a technology by which a user's view of the real world is augmented with additional information from a computer model. In this paper, the applications of augmented reality technology to hydraulic engineering are reported for the first time .Furthermore, augmented reality based on affine invariants as well as its research method and application background is discussed, and thus the fusion between virtual objects and reality image is realized.

  1. Energy Efficiency Comparison between Hydraulic Hybrid and Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jia-Shiun Chen

    2015-05-01

    Full Text Available Conventional vehicles tend to consume considerable amounts of fuel, which generates exhaust gases and environmental pollution during intermittent driving cycles. Therefore, prospective vehicle designs favor improved exhaust emissions and energy consumption without compromising vehicle performance. Although pure electric vehicles feature high performance and low pollution characteristics, their limitations are their short driving range and high battery costs. Hybrid electric vehicles (HEVs are comparatively environmentally friendly and energy efficient, but cost substantially more compared with conventional vehicles. Hydraulic hybrid vehicles (HHVs are mainly operated using engines, or using alternate combinations of engine and hydraulic power sources while vehicles accelerate. When the hydraulic system accumulator is depleted, the conventional engine reengages; concurrently, brake-regenerated power is recycled and reused by employing hydraulic motor–pump modules in circulation patterns to conserve fuel and recycle brake energy. This study adopted MATLAB Simulink to construct complete HHV and HEV models for backward simulations. New European Driving Cycles were used to determine the changes in fuel economy. The output of power components and the state-of-charge of energy could be retrieved. Varying power component models, energy storage component models, and series or parallel configurations were combined into seven different vehicle configurations: the conventional manual transmission vehicle, series hybrid electric vehicle, series hydraulic hybrid vehicle, parallel hybrid electric vehicle, parallel hydraulic hybrid vehicle, purely electric vehicle, and hydraulic-electric hybrid vehicle. The simulation results show that fuel consumption was 21.80% lower in the series hydraulic hybrid vehicle compared to the series hybrid electric vehicle; additionally, fuel consumption was 3.80% lower in the parallel hybrid electric vehicle compared to the

  2. Coupled Numerical Study of Turbidity Currents, Internal Hydraulic Jump and Morphological Signatures

    Science.gov (United States)

    Hu, P.; Cao, Z.; He, Z.; Gareth, P.

    2013-12-01

    on hydraulic jumps in turbidity currents near a canyon-fan transition. Science, 245(4916), 393-396. Hu, P., Cao, Z., Pender, G. (2012). Well-balanced two-dimensional coupled modelling of submarine turbidity currents. Proceedings of the ICE-Maritime Engineering, 165(4), 169-188. Kostic, S., and Parker, G. (2006). The response of turbidity currents to a canyon-fan transition: internal hydraulic jumps and depositional signatures. Journal of Hydraulic Research, IAHR, 44(5), 631-653. Parker, G., Fukushima, Y., Pantin, H. (1986). Self-accelerating turbidity currents. Journal of Fluid Mechanics, 171, 145-181.

  3. Free Energy and Internal Combustion Engine Cycles

    CERN Document Server

    Harris, William D

    2012-01-01

    The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

  4. FEMA DFIRM Hydraulic Structures

    Data.gov (United States)

    Minnesota Department of Natural Resources — This layer and accompanying attribute table is required whenever hydraulic structures are shown in the flood profile. It is also required if levees are shown on the...

  5. 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.

  6. Lunar nuclear power plant design for thermal-hydraulic cooling in nano-scale environment: Nuclear engineering-based interdisciplinary nanotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Tae Ho [Systemix Global Co. Ltd., Seoul (Korea, Republic of)

    2015-05-15

    The environment of the Moon is nearly vacant, which has very low density of several kinds of gases. It has the molecular level contents of the lunar atmosphere in Table 1, which is recognized that radiation heat transfer is a major cooling method. The coolant of the nuclear power plant (NPP) in the lunar base is the Moon surface soil , which is known as the regolith. The regolith is the layer of loose and heterogeneous material covering the solid rock. For finding the optimized length of the radiator of the coolant in the lunar NPP, the produced power and Moon environmental temperature are needed. This makes the particular heat transfer characteristics in heat transfer in the Moon surface. The radiation is the only heat transfer way due to very weak atmosphere. It is very cold in the night time and very hot in the daytime on the surface of the ground. There are comparisons between lunar high land soil and Earth averages in Table 2. In the historical consideration, Konstantin Tsiolkovsky made a suggestion for the colony on the Moon.. There are a number of ideas for the conceptual design which have been proposed by several scientists. In 1954, Arthur C. Clarke mentioned a lunar base of inflatable modules covered in lunar dust for insulation. John S. Rinehart suggested the structure of the stationary ocean of dust, because there could be a mile-deep dust ocean on the Moon, which gives a safer design. In 1959, the project horizon was launched regarding the U.S. Army's plan to establish a fort on the Moon by 1967. H. H. Koelle, a German rocket engineer of the Army Ballistic Missile Agency, leaded the project (ABMA). There was the first landing in 1965 and 245 tons of cargos were transported to the outpost by 1966. The coolant material of regolith in the Moon is optimized for the NPP. By the simulation, there are some results. The temperature is calculated as the 9 nodals by radiation heat transfer from the potassium coolant to the regolith flow. The high efficiency

  7. Legal Ice?

    DEFF Research Database (Denmark)

    Strandsbjerg, Jeppe

    The idealised land|water dichotomy is most obviously challenged by ice when ‘land practice’ takes place on ice or when ‘maritime practice’ is obstructed by ice. Both instances represent disparity between the legal codification of space and its social practice. Logically, then, both instances call...... for alternative legal thought and practice; in the following I will emphasise the former and reflect upon the relationship between ice, law and politics. Prior to this workshop I had worked more on the relationship between cartography, geography and boundaries than specifically on ice. Listening to all...... the interesting conversations during the workshop, however, made me think that much of the concern with the Polar Regions in general, and the presence of ice in particular, reverberates around the question of how to accommodate various geographical presences and practices within the regulatory framework that we...

  8. Under-ice movement of cohesive sediments before river-ice breakup

    Science.gov (United States)

    Milburn, D.; Prowse, T. D.

    2002-03-01

    A significant body of research exists on river hydraulics and sediment transport during open-water conditions, and to a lesser extent during the period of ice-cover. Most of the ice-related studies, however, are based on controlled laboratory experiments or field studies conducted under stable ice-cover conditions. They have largely ignored the most dynamic periods, such as breakup, when hydraulic conditions are most rapidly changing and energy levels are maximized. Moreover, the entire pre-breakup to ice-clearance period is virtually devoid of even standard hydrometric measurements of suspended sediment, largely because of safety and logistic problems. Some recent work has pointed to the formation of a sediment plume comprising fine-grained sediments that develops before the main breakup fracturing of the ice cover. This plume has been noted as being particularly ecologically significant because it can contain the winter-long deposition of contaminants that preferentially attach to fine-grained material. Unfortunately, however, because measurements of the critical parameters affecting sediment transport during these periods are rarely taken, much uncertainty remains about the hydraulic forces that resuspend and transport sediments under an ice cover, and particularly for cohesive fine-grained sediments. This paper describes a field experiment designed to broaden our understanding of sediment transport during this critical pre-breakup period. Detailed measurements of river stage, ice elevations, flow velocity profiles and suspended sediment were taken over a 17-day period just before the 1998 river-ice breakup at Hay River, Northwest Territories, Canada. Results indicated that just before breakup, the shear stress, which governs the beginning of sediment motion, increases dramatically and drives the development of the under-ice sediment plume of very fine-grained, cohesive sediments. The shear stress in this case became critical at a mean under-ice velocity of 0·4

  9. Sea Ice

    Science.gov (United States)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.

    2013-01-01

    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  10. Lubrication and tribology in seawater hydraulic piston pump

    Institute of Scientific and Technical Information of China (English)

    WANG Dong; LI Zhuang-yun; ZHU Yu-quan

    2003-01-01

    Water hydraulic systems have provoked major interest because of the human friendly and environmental safety aspects. Piston pump is one of the most frequently used hydraulic units in recent engineering technique. In water hydraulic piston pump, poor lubrication is more likely to happen than in oil hydraulic one because of difference in properties between water and oil. So there are some key problems such as corrosive wear and erosion, which are investigated briefly. Many new materials have been developed, which give longer life expectancies with water without corrosion and erosion. A new type of seawater hydraulic piston pumps with better suction characteristics had been developed at HUST. Much of this research has concentrated on new materials, structure and experiments, which are also specially introduced.

  11. Hydraulic integration and shrub growth form linked across continental aridity gradients.

    Science.gov (United States)

    Schenk, H Jochen; Espino, Susana; Goedhart, Christine M; Nordenstahl, Marisa; Cabrera, Hugo I Martinez; Jones, Cynthia S

    2008-08-12

    Both engineered hydraulic systems and plant hydraulic systems are protected against failure by resistance, reparability, and redundancy. A basic rule of reliability engineering is that the level of independent redundancy should increase with increasing risk of fatal system failure. Here we show that hydraulic systems of plants function as predicted by this engineering rule. Hydraulic systems of shrubs sampled along two transcontinental aridity gradients changed with increasing aridity from highly integrated to independently redundant modular designs. Shrubs in humid environments tend to be hydraulically integrated, with single, round basal stems, whereas dryland shrubs typically have modular hydraulic systems and multiple, segmented basal stems. Modularity is achieved anatomically at the vessel-network scale or developmentally at the whole-plant scale through asymmetric secondary growth, which results in a semiclonal or clonal shrub growth form that appears to be ubiquitous in global deserts.

  12. Icing modelling in NSMB with chimera overset grids

    Energy Technology Data Exchange (ETDEWEB)

    Pena, D. [Ècole Polytechnique de Montréal (Canada); ICUBE, Strasbourg University (France); Deloze, T.; Laurendeau, E. [Ècole Polytechnique de Montréal (Canada); Hoarau, Y. [ICUBE, Strasbourg University (France)

    2015-03-10

    In aerospace Engineering, the accurate simulation of ice accretion is a key element to increase flight safety and avoid accidents related to icing effects. The icing code developed in the NSMB solver is based on an Eulerian formulation for droplets tracking, an iterative Messinger model using a modified water runback scheme for ice thickness calculation and mesh deformation to track the ice/air interface through time. The whole process is parallelized with MPI and applied with chimera grids.

  13. Trend of hydraulic units

    Energy Technology Data Exchange (ETDEWEB)

    Deshimaru, Jun' ichi

    1988-11-01

    The gear, vane and piston pumps occupy a more then 90% share in the hydraulic pumps. Comparatively large pumps are mainly variable delivery piston pumps. The piston pumps are comparatively high in output density (output per unit weight), indicating the hydraulic pump in performance, and tend to become higher and higher in it. Though they are mainly 210 to 350kgf/cm/sup 2/ in rated pressure, some of them come to surpass 400kgf/cm/sup 3/ in it. While the progress in computation also requires the high speed operation, high accuracy and other severe conditions for the hydraulic units, which accordingly and increasingly intensify the requirement for hydraulic oil in abrasion resistibility, oxidation stability and response characteristics. While cavitation comes to easily occur, which considerably and disadvantageously influences hydraulic oil in life through degradation, noise level and respondingness. From now on, the development of high performance oil and study of mechanical structure are important. 19 references, 9 figures, 2 tables.

  14. Interstellar Ices

    CERN Document Server

    Boogert, A C A

    2003-01-01

    Currently ~36 different absorption bands have been detected in the infrared spectra of cold, dense interstellar and circumstellar environments. These are attributed to the vibrational transitions of ~17 different molecules frozen on dust grains. We review identification issues and summarize the techniques required to extract information on the physical and chemical evolution of these ices. Both laboratory simulations and line of sight studies are essential. Examples are given for ice bands observed toward high mass protostars, fields stars and recent work on ices in disks surrounding low mass protostars. A number of clear trends have emerged in recent years. One prominent ice component consists of an intimate mixture between H2O, CH3OH and CO2 molecules. Apparently a stable balance exists between low temperature hydrogenation and oxidation reactions on grain surfaces. In contrast, an equally prominent ice component, consisting almost entirely of CO, must have accreted directly from the gas phase. Thermal proc...

  15. Smoothed Particle Hydrodynamic of Hydraulic Jumps in Spillways

    OpenAIRE

    Jonsson, Patrick

    2015-01-01

    This thesis focus on the complex natural phenomena of hydraulic jumps using the numerical method Smoothed Particle Hydrodynamics (SPH). A hydraulic jump is highly turbulent and associated with turbulent energy dissipation, air entrainment, surface waves and spray and strong dissipative processes. It can be found not only in natural streams and in engineered open channels, but also in your kitchen sink at home. The dissipative features are utilized in hydropower spillways and stilling basins t...

  16. KJRR-FAI Hydraulic Flow Testing Input Package

    Energy Technology Data Exchange (ETDEWEB)

    N.E. Woolstenhulme; R.B. Nielson; D.B. Chapman

    2013-12-01

    The INL, in cooperation with the KAERI via Cooperative Research And Development Agreement (CRADA), undertook an effort in the latter half of calendar year 2013 to produce a conceptual design for the KJRR-FAI campaign. The outcomes of this effort are documented in further detail elsewhere [5]. The KJRR-FAI was designed to be cooled by the ATR’s Primary Coolant System (PCS) with no provision for in-pile measurement or control of the hydraulic conditions in the irradiation assembly. The irradiation assembly was designed to achieve the target hydraulic conditions via engineered hydraulic losses in a throttling orifice at the outlet of the irradiation vehicle.

  17. Hydraulics for Royal Gardens: Water Art as a Challenge for 18th Century Science and 21st Century Physics Teaching

    Science.gov (United States)

    Eckert, Michael

    2007-01-01

    Hydraulics is an engineering specialty and largely neglected as a topic in physics teaching. But the history of hydraulics from the Renaissance to the Baroque, merits our attention because hydraulics was then more broadly conceived as a practical "and" theoretical science; it served as a constant bone of contention for mechanics and…

  18. Hydraulics for Royal Gardens: Water Art as a Challenge for 18th Century Science and 21st Century Physics Teaching

    Science.gov (United States)

    Eckert, Michael

    2007-01-01

    Hydraulics is an engineering specialty and largely neglected as a topic in physics teaching. But the history of hydraulics from the Renaissance to the Baroque, merits our attention because hydraulics was then more broadly conceived as a practical "and" theoretical science; it served as a constant bone of contention for mechanics and…

  19. Cavitation in Hydraulic Machinery

    Energy Technology Data Exchange (ETDEWEB)

    Kjeldsen, M.

    1996-11-01

    The main purpose of this doctoral thesis on cavitation in hydraulic machinery is to change focus towards the coupling of non-stationary flow phenomena and cavitation. It is argued that, in addition to turbulence, superimposed sound pressure fluctuations can have a major impact on cavitation and lead to particularly severe erosion. For the design of hydraulic devices this finding may indicate how to further limit the cavitation problems. Chapter 1 reviews cavitation in general in the context of hydraulic machinery, emphasizing the initial cavitation event and the role of the water quality. Chapter 2 discusses the existence of pressure fluctuations for situations common in such machinery. Chapter 3 on cavitation dynamics presents an algorithm for calculating the nucleation of a cavity cluster. Chapter 4 describes the equipment used in this work. 53 refs., 55 figs.,10 tabs.

  20. Popeye Project: Hydraulic umbilical

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, K.G.; Williams, V.T.

    1996-12-31

    For the Popeye Project, the longest super-duplex hydraulic umbilical in the world was installed in the Gulf of Mexico. This paper reports on its selection and project implementation. Material selection addresses corrosion in seawater, water-based hydraulic fluid, and methanol. Five alternatives were considered: (1) carbon-steel with traditional coating and anodes, (2) carbon-steel coated with thermally sprayed aluminum, (3) carbon-steel sheathed in aluminum, (4) super-duplex, and (5) titanium. The merits and risks associated with each alternative are discussed. The manufacture and installation of the selected umbilical are also reported.

  1. Ice tectonics during the rapid tapping of a supraglacial lake on the Greenland Ice Sheet

    Directory of Open Access Journals (Sweden)

    S. H. Doyle

    2012-09-01

    Full Text Available The hydraulic fracture of ice during the rapid tapping of supraglacial lakes is proposed as one mechanism to establish efficient surface-to-bed hydraulic pathways through kilometre-thick ice. This study presents detailed records of lake discharge, ice motion, and passive seismicity capturing the behaviour and processes preceding, during and following the rapid (~2 h tapping of a large (~4 km2 supraglacial lake through 1.1 km of the western margin of the Greenland Ice Sheet. Peak discharge (3300 m3s−1 was coincident with maximal rates of horizontal displacement and vertical uplift, indicating that surface water accessed the ice-bed interface causing widespread hydraulic separation and enhanced basal motion. The differential motion of four GPS located around the lake, record the opening and closure of fractures suggesting that on short time-scales the brittle fracture of ice dominates ice flow. We hypothesise that during lake tapping, drainage occurred through a ~3 km long longitudinal fracture with a mean width of ~0.4 m. The perennial location of the supraglacial lake and the observed pattern of fracturing and surface uplift evince control by the local subglacial topography and the gradient of hydraulic potential. Our observations support the assertion that water-filled crevasses can propagate without longitudinal extension. The tapping of the lake coincided with the rapid drainage of a cluster of supraglacial lakes located within the same elevation band coincident with a notable and isolated peak in the catchment-wide, proglacial Watson River hydrograph.

  2. Investigation and Development of the Thermal Preparation System of the Trailbuilder Machinery Hydraulic Actuator

    Science.gov (United States)

    Konev, V.; Polovnikov, E.; Krut, O.; Merdanov, Sh; Zakirzakov, G.

    2017-07-01

    It’s determined that the main part of trailbuilders operated in the North is the technology equipped by the hydraulic actuator. Further development of the northern territories will demand using of various means and ways machinery thermal preparation, and also the machinery of the northern fulfillment. On this basis problems in equipment operation are defined. One of the main is efficiency supplying of a hydraulic actuator. On the basis of the operating conditions’ analysis of trailbuilder hydraulic actuator operation it is determined, that under low negative temperatures the means of thermal preparation are necessary. The existing systems warm up only a hydraulic tank or warming up of the hydro equipment before the machinery operation is carried out under loading with intensive wears. Thus, with the purpose to raise the efficiency of thermal hydraulic actuator, operated far from stationary bases autonomous, energy saving, not expensive in creation and operation systems are necessary. In accordance with the analysis of means and ways of the thermal preparation of the hydraulic actuator and the thermal balance calculations of the (internal) combustion engine the system of the hydraulic actuator heating is offered and is being investigated. It contains a local hydraulic actuator warming up and the system of internal combustion engine heat utilization. Within research operation conditions of the local hydraulic actuator heating are viewed and determined, taking into account constructive changes to the local hydraulic actuator heating. Mathematical modelling of the heat technical process in the modernized hydraulic actuator is considered. As a result temperature changes of the heat-transfer and the hydraulic cylinder in time are determined. To check the theoretical researches and to define dependences on hydraulic actuator warming up, the experimental installation is made. It contains the measuring equipment, a small tank with the heat exchanger of the burnt gases

  3. Archimedean Ice

    CERN Document Server

    Eloranta, Kari

    2009-01-01

    The striking boundary dependency (the Arctic Circle phenomenon) exhibited in the ice model on the square lattice extends to other planar set-ups. We present these findings for the triangular and the Kagome lattices. Critical connectivity results guarantee that ice configurations can be generated using the simplest and most efficient local actions. Height functions are utilized throughout the analysis. At the end there is a surprise in store: on the remaining Archimedean lattice for which the ice model can be defined, the 3.4.6.4. lattice, the long range behavior is completely different from the other cases.

  4. HYDRAULICS, TUSCARAWAS COUNTY, OHIO, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydraulic procedures for estimating flood discharges for a flood insurance...

  5. Hydraulic hoist-press

    Energy Technology Data Exchange (ETDEWEB)

    Babayev, Z.B.; Abashev, Z.V.

    1982-01-01

    The efficiency expert of the Angrenskiy production-technological administration of the production association Sredazugol A. V. Bubnov has suggested a hydraulic hoist-press for repairing road equipment which is a device consisting of lifting mechanism, press and test stand for verifying the high pressure hoses and pumps.

  6. Modelling of Hydraulic Robot

    DEFF Research Database (Denmark)

    Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

    1997-01-01

    This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...

  7. Water Treatment Technology - Hydraulics.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on hydraulics 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: head loss in pipes in series, function loss in…

  8. Water Hydraulic Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

    The paper presents research results using IT-Tools for CAD and dynamic modelling, simulation, analysis, and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. Matlab/Simulink and CATIA are used as IT-Tools. The contributions include results from on-going...

  9. Calculation Method and Distribution Characteristics of Fracture Hydraulic Aperture from Field Experiments in Fractured Granite Area

    Science.gov (United States)

    Cao, Yang-Bing; Feng, Xia-Ting; Yan, E.-Chuan; Chen, Gang; Lü, Fei-fei; Ji, Hui-bin; Song, Kuang-Yin

    2016-05-01

    Knowledge of the fracture hydraulic aperture and its relation to the mechanical aperture and normal stress is urgently needed in engineering construction and analytical research at the engineering field scale. A new method based on the in situ borehole camera measurement and borehole water-pressure test is proposed for the calculation of the fracture hydraulic aperture. This method comprises six steps. The first step is to obtain the equivalent hydraulic conductivity of the test section from borehole water-pressure tests. The second step is a tentative calculation to obtain the qualitative relation between the reduction coefficient and the mechanical aperture obtained from borehole camera measurements. The third step is to choose the preliminary reduction coefficient for obtaining the initial hydraulic aperture. The remaining three steps are to optimize, using the genetic algorithm, the hydraulic apertures of fractures with high uncertainty. The method is then applied to a fractured granite engineering area whose purpose is the construction of an underground water-sealed storage cavern for liquefied petroleum gas. The probability distribution characteristics of the hydraulic aperture, the relationship between the hydraulic aperture and the mechanical aperture, the hydraulic aperture and the normal stress, and the differences between altered fractures and fresh fractures are all analyzed. Based on the effects of the engineering applications, the method is proved to be feasible and reliable. More importantly, the results of the hydraulic aperture obtained in this paper are different from those results elicited from laboratory tests, and the reasons are discussed in the paper.

  10. Ice sheet hydrology - a review

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Peter; Naeslund, Jens-Ove [Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden); Rodhe, Lars [Geological Survey of Sweden, Uppsala (Sweden)

    2007-03-15

    This report summarizes the theoretical knowledge on water flow in and beneath glaciers and ice sheets and how these theories are applied in models to simulate the hydrology of ice sheets. The purpose is to present the state of knowledge and, perhaps more importantly, identify the gaps in our understanding of ice sheet hydrology. Many general concepts in hydrology and hydraulics are applicable to water flow in glaciers. However, the unique situation of having the liquid phase flowing in conduits of the solid phase of the same material, water, is not a commonly occurring phenomena. This situation means that the heat exchange between the phases and the resulting phase changes also have to be accounted for in the analysis. The fact that the solidus in the pressure-temperature dependent phase diagram of water has a negative slope provides further complications. Ice can thus melt or freeze from both temperature and pressure variations or variations in both. In order to provide details of the current understanding of water flow in conjunction with deforming ice and to provide understanding for the development of ideas and models, emphasis has been put on the mathematical treatments, which are reproduced in detail. Qualitative results corroborating theory or, perhaps more often, questioning the simplifications made in theory, are also given. The overarching problem with our knowledge of glacier hydrology is the gap between the local theories of processes and the general flow of water in glaciers and ice sheets. Water is often channelized in non-stationary conduits through the ice, features which due to their minute size relative to the size of glaciers and ice sheets are difficult to incorporate in spatially larger models. Since the dynamic response of ice sheets to global warming is becoming a key issue in, e.g. sea-level change studies, the problems of the coupling between the hydrology of an ice sheet and its dynamics is steadily gaining interest. New work is emerging

  11. 水工环氧防护修补材料应力松弛性能研究%Study of stress relaxation behavior of hydraulic engineering epoxy resin repairing material

    Institute of Scientific and Technical Information of China (English)

    赵波; 李敬玮; 鲁一晖

    2011-01-01

    An experimental study is made on the creep and stress relaxation behavior of the hydraulic engineering epoxy resin repairing material developed in laboratory of IWHR. The material initial elastic modulus of 1. 41 Gpa is determined for the material by the testing of DMTA (Dynamic Mechanical Thermal Analysis) and the stress relaxation function of the material is obtained through the Laplace transform based on the Kelvin model along with the double retardation time and standard linear solid model. The result shows that the result from the standard linear solid model is close to that from the Kelvin model of double retardation time under the temperature of -20 t, however, the result from the Kelvin model is even much more close to the physical character of the material within a bigger temperature scope. The test result indicates that this epoxy resin material has a better mechanical relaxation behavior under a lower temperature condition.%对实验室研制的水工环氧防护材料的蠕变和应力松弛行为进行了试验研究.采用DMTA测试确定材料的起始弹性模量为1.41 GPa,结合蠕变实验结果,采用双推迟时间Kelvin模型和标准线性固体模型,通过Laplace变换得到了材料的应力松弛函数.结果表明:在- 20℃条件下,标准线性固体模型得到的结果接近于双推迟时间的Kelvin模型结果,但较宽温度范围内Kelvin模型更接近于材料的实际物理状态.试验结果表明该环氧修补材料在低温情况下具有较好的力学松弛性能.

  12. CFD Modeling of Mixed-Phase Icing

    Science.gov (United States)

    Zhang, Lifen; Liu, Zhenxia; Zhang, Fei

    2016-12-01

    Ice crystal ingestion at high altitude has been reported to be a threat for safe operation of aero-engine in recently. Ice crystals do not accrete on external surface because of cold environment. But when they enter the core flow of aero-engine, ice crystals melt partially into droplets due to higher temperature. Air-droplets-ice crystal is the mixed-phase, which will give rise to ice accretion on static and rotating components in compressor. Subsequently, compressor surge and engine shutdowns may occur. To provide a numerical tool to analyze this in detail, a numerical method was developed in this study. The mixed phase flow was solved using Eulerian-Lagrangian method. The dispersed phase was represented by one-way coupling. A thermodynamic model that considers mass and energy balance with ice crystals and droplets was presented as well. The icing code was implemented by the user-defined function of Fluent. The method of ice accretion under mixed-phase conditions was validated by comparing the results simulated on a cylinder with experimental data derived from literature. The predicted ice shape and mass agree with these data, thereby confirming the validity of the numerical method developed in this research for mixed-phase conditions.

  13. Hydraulic manipulator research at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States); Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States)

    1997-03-01

    Recently, task requirements have dictated that manipulator payload capacity increase to accommodate greater payloads, greater manipulator length, and larger environmental interaction forces. General tasks such as waste storage tank cleanup and facility dismantlement and decommissioning require manipulator life capacities in the range of hundreds of pounds rather than tens of pounds. To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned once again to hydraulics as a means of actuation. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem), sophisticated modeling, analysis, and control experiments are usually needed. Oak Ridge National Laboratory (ORNL) has a history of projects that incorporate hydraulics technology, including mobile robots, teleoperated manipulators, and full-scale construction equipment. In addition, to support the development and deployment of new hydraulic manipulators, ORNL has outfitted a significant experimental laboratory and has developed the software capability for research into hydraulic manipulators, hydraulic actuators, hydraulic systems, modeling of hydraulic systems, and hydraulic controls. The purpose of this article is to describe the past hydraulic manipulator developments and current hydraulic manipulator research capabilities at ORNL. Included are example experimental results from ORNL`s flexible/prismatic test stand.

  14. 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.

  15. HYBRID CONTROL OF HYDRAULIC PRESS MACHINE BASED ON ROBUST CONTROL

    Institute of Scientific and Technical Information of China (English)

    FANG Yu; YANG Jian; CHAI Xiaodong

    2008-01-01

    A robust control algorithm is proposed to focus on the non-linearity and variables of the hydraulic press machine with the proportional valve. The proposed robust controller does not need to design stable compensator in advance, which is simple in design and has large scope of uncertainty applications. The feedback gains of the proposed robust controller are small, so it is easily implemented in engineering applications. The theoretical and experimental research on the position and speed control of the hydraulic press machine is carried out. The control requirements of the hydraulic press machine during the working process are met in the position and speed at the same time. Experimental results show that the proposed controller has better robustness subject to load variables and adaptability of parameter variations of the hydraulic press machine with the proportional valve.

  16. Education for hydraulics and pneumatics in Nihon University; Nihon Daigaku ni okeru yukuatsu kyoiku

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, M. [Nihon Univ., Chiba (Japan). Coll. of Industrial Technology

    2000-03-15

    Described herein is education of hydraulics and pneumatics in Nihon University. Department of Mechanical Engineering of Faculty of Production Engineering has been holding up the educational aims of bringing up engineers and researchers who have ability and intelligence to cope with internationalization and contribute to society, and of bringing about creativity, among others. Control equipment is an optional subject for the sophomore class in the second semester, and is centered by mechatronics, including hydraulic and pneumatic control systems and equipment. The related subjects include fluid dynamics, control engineering, system controlling, hydraulic machines, robotics and automobile engineering. The drill course includes disassembling and assembling gear pumps, drills on pneumatic devices, system behavior and mechatronics, experiments on fan and hydraulic control circuits and on servo mechanisms, and machinery designs and drawings. Seminars are led by full-time or part-time lecturers for the themes related to hydraulic power. Many students are interested in hydraulic and pneumatic themes for their graduation theses, because of their relations with control, environments, energy saving and so on. We are now in the age of composite technologies, and hydraulic power basics are prerequisite for engineers, and important for education of students. (NEDO)

  17. Undular Hydraulic Jump

    Directory of Open Access Journals (Sweden)

    Oscar Castro-Orgaz

    2015-04-01

    Full Text Available The transition from subcritical to supercritical flow when the inflow Froude number Fo is close to unity appears in the form of steady state waves called undular hydraulic jump. The characterization of the undular hydraulic jump is complex due to the existence of a non-hydrostatic pressure distribution that invalidates the gradually-varied flow theory, and supercritical shock waves. The objective of this work is to present a mathematical model for the undular hydraulic jump obtained from an approximate integration of the Reynolds equations for turbulent flow assuming that the Reynolds number R is high. Simple analytical solutions are presented to reveal the physics of the theory, and a numerical model is used to integrate the complete equations. The limit of application of the theory is discussed using a wave breaking condition for the inception of a surface roller. The validity of the mathematical predictions is critically assessed using physical data, thereby revealing aspects on which more research is needed

  18. A spongy icing model for aircraft icing

    Institute of Scientific and Technical Information of China (English)

    Li Xin; Bai Junqiang; Hua Jun; Wang Kun; Zhang Yang

    2014-01-01

    Researches have indicated that impinging droplets can be entrapped as liquid in the ice matrix and the temperature of accreting ice surface is below the freezing point. When liquid entrapment by ice matrix happens, this kind of ice is called spongy ice. A new spongy icing model for the ice accretion problem on airfoil or aircraft has been developed to account for entrapped liquid within accreted ice and to improve the determination of the surface temperature when enter-ing clouds with supercooled droplets. Different with conventional icing model, this model identifies icing conditions in four regimes:rime, spongy without water film, spongy with water film and glaze. By using the Eulerian method based on two-phase flow theory, the impinging droplet flow was investigated numerically. The accuracy of the Eulerian method for computing the water collection efficiency was assessed, and icing shapes and surface temperature distributions predicted with this spongy icing model agree with experimental results well.

  19. A spongy icing model for aircraft icing

    Directory of Open Access Journals (Sweden)

    Li Xin

    2014-02-01

    Full Text Available Researches have indicated that impinging droplets can be entrapped as liquid in the ice matrix and the temperature of accreting ice surface is below the freezing point. When liquid entrapment by ice matrix happens, this kind of ice is called spongy ice. A new spongy icing model for the ice accretion problem on airfoil or aircraft has been developed to account for entrapped liquid within accreted ice and to improve the determination of the surface temperature when entering clouds with supercooled droplets. Different with conventional icing model, this model identifies icing conditions in four regimes: rime, spongy without water film, spongy with water film and glaze. By using the Eulerian method based on two-phase flow theory, the impinging droplet flow was investigated numerically. The accuracy of the Eulerian method for computing the water collection efficiency was assessed, and icing shapes and surface temperature distributions predicted with this spongy icing model agree with experimental results well.

  20. A 6-DOF vibration isolation system for hydraulic hybrid vehicles

    Science.gov (United States)

    Nguyen, The; Elahinia, Mohammad; Olson, Walter W.; Fontaine, Paul

    2006-03-01

    This paper presents the results of vibration isolation analysis for the pump/motor component of hydraulic hybrid vehicles (HHVs). The HHVs are designed to combine gasoline/diesel engine and hydraulic power in order to improve the fuel efficiency and reduce the pollution. Electric hybrid technology is being applied to passenger cars with small and medium engines to improve the fuel economy. However, for heavy duty vehicles such as large SUVs, trucks, and buses, which require more power, the hydraulic hybridization is a more efficient choice. In function, the hydraulic hybrid subsystem improves the fuel efficiency of the vehicle by recovering some of the energy that is otherwise wasted in friction brakes. Since the operation of the main component of HHVs involves with rotating parts and moving fluid, noise and vibration are an issue that affects both passengers (ride comfort) as well as surrounding people (drive-by noise). This study looks into the possibility of reducing the transmitted noise and vibration from the hydraulic subsystem to the vehicle's chassis by using magnetorheological (MR) fluid mounts. To this end, the hydraulic subsystem is modeled as a six degree of freedom (6-DOF) rigid body. A 6-DOF isolation system, consisting of five mounts connected to the pump/motor at five different locations, is modeled and simulated. The mounts are designed by combining regular elastomer components with MR fluids. In the simulation, the real loading and working conditions of the hydraulic subsystem are considered and the effects of both shock and vibration are analyzed. The transmissibility of the isolation system is monitored in a wide range of frequencies. The geometry of the isolation system is considered in order to sustain the weight of the hydraulic system without affecting the design of the chassis and the effectiveness of the vibration isolating ability. The simulation results shows reduction in the transmitted vibration force for different working cycles of

  1. The Integrated and Standardized Informatization Application of Hydraulic Engineering Management in Hydropower Enterprises%水电厂水工管理的一体化、标准化、信息化实践

    Institute of Scientific and Technical Information of China (English)

    李国东; 刘双华; 徐伟; 吴宏炜

    2014-01-01

    水电厂由于所处地理环境、地质地形条件、管理模式等的不同,水工管理工作差异比较大。本文以国网新源控股有限公司水电生产管理信息系统建设为背景,阐述了公司水工管理标准,构建了系统水工管理功能和标准流程,实现了集团级水工管理的信息化,通过系统推广应用,有效规范该公司水工管理工作,提高了水工设施安全健康水平。%Hydraulic management in different hydropower power plants are quite different due to various geography environ-ment,geology and the topography as well as the management methodologies.Based on the implementation of HPMS(Hydro-power Production Management Information System)in SG Xin Yuan(State Grid Xin Yuan Company Ltd.),this paper elabo-rates the standards of hydraulic management,establishes the systematic functions and standard process,which not only realize and regulate the group-level hydraulic management information systems as well as improve the safe and health status of hy-draulic equipments.

  2. EXPERIMENTAL RESEARCH FOCUSED ON YIELDS OF LINEARE HYDRAULIC MOTORS USED TO DRIVE THE BOTTOM PUMPS

    Directory of Open Access Journals (Sweden)

    Petre SĂVULESCU

    2011-07-01

    Full Text Available This paper presents the authors’s concerns for determining the functional parameters and its yieldsfor a linear hydraulic engine with double effect. Functional parameters are determined both at unloadedrunning and loaded running of the linear hydraulic motor. The yields was determined on loaded running.

  3. EXPERIMENTAL RESEARCH FOCUSED ON YIELDS OF LINEARE HYDRAULIC MOTORS USED TO DRIVE THE BOTTOM PUMPS

    OpenAIRE

    Petre SĂVULESCU

    2011-01-01

    This paper presents the authors’s concerns for determining the functional parameters and its yieldsfor a linear hydraulic engine with double effect. Functional parameters are determined both at unloadedrunning and loaded running of the linear hydraulic motor. The yields was determined on loaded running.

  4. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    OpenAIRE

    HUANG, Ye; Liu, Changsheng; Shiongur Bamed

    2014-01-01

    Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under...

  5. Using Remote Sensing Data to Parameterize Ice Jam Modeling for a Northern Inland Delta

    Directory of Open Access Journals (Sweden)

    Fan Zhang

    2017-04-01

    Full Text Available The Slave River is a northern river in Canada, with ice being an important component of its flow regime for at least half of the year. During the spring breakup period, ice jams and ice-jam flooding can occur in the Slave River Delta, which is of benefit for the replenishment of moisture and sediment required to maintain the ecological integrity of the delta. To better understand the ice jam processes that lead to flooding, as well as the replenishment of the delta, the one-dimensional hydraulic river ice model RIVICE was implemented to simulate and explore ice jam formation in the Slave River Delta. Incoming ice volume, a crucial input parameter for RIVICE, was determined by the novel approach of using MODIS space-born remote sensing imagery. Space-borne and air-borne remote sensing data were used to parameterize the upstream ice volume available for ice jamming. Gauged data was used to complement modeling calibration and validation. HEC-RAS, another one-dimensional hydrodynamic model, was used to determine ice volumes required for equilibrium jams and the upper limit of ice volume that a jam can sustain, as well as being used as a threshold for the volumes estimated by the dynamic ice jam simulations using RIVICE. Parameter sensitivity analysis shows that morphological and hydraulic properties have great impacts on the ice jam length and water depth in the Slave River Delta.

  6. Freezeup Dynamics of a Frazil Ice Screen

    Science.gov (United States)

    1990-02-01

    Vh~FILE COPY * AD-A219 588 Freezeup Dynamics of a Frazil Ice Screen Kathleen D. Axelson February 1990 * DTIC a 3 ELECTU Apprcv . f pti’L r, 1 Distl...U Special Report 90-4 U.S. Army Corps of Engineers Cold Regions Research & Engineering Laboratory Freezeup Dynamics of a Frazil Ice Screen Kathleen D...not constitute an official endorsement or approval of the use of such commercial products. Freezeup Dynamics of a Frazil Ice Screen KATHLEEN D. AXELSON

  7. Hydraulic System Design of Hydraulic Actuators for Large Butterfly Valves

    Directory of Open Access Journals (Sweden)

    Ye HUANG

    2014-09-01

    Full Text Available Hydraulic control systems of butterfly valves are presently valve-controlled and pump-controlled. Valve-controlled hydraulic systems have serious power loss and generate much heat during throttling. Pump-controlled hydraulic systems have no overflow or throttling losses but are limited in the speed adjustment of the variable-displacement pump, generate much noise, pollute the environment, and have motor power that does not match load requirements, resulting in low efficiency under light loads and wearing of the variable-displacement pump. To overcome these shortcomings, this article designs a closed hydraulic control system in which an AC servo motor drives a quantitative pump that controls a spiral swinging hydraulic cylinder, and analyzes and calculates the structure and parameters of a spiral swinging hydraulic cylinder. The hydraulic system adjusts the servo motor’s speed according to the requirements of the control system, and the motor power matches the power provided to components, thus eliminating the throttling loss of hydraulic circuits. The system is compact, produces a large output force, provides stable transmission, has a quick response, and is suitable as a hydraulic control system of a large butterfly valve.

  8. SEISM SAFETY OF PRESSURE HEAD HYDRAULIC ENGINEERING CONSTRUCTIONS Сейсмобезопасность напорных гидротехнических сооружений

    Directory of Open Access Journals (Sweden)

    Volosoukhin V. A.

    2012-04-01

    Full Text Available Experience of supervision of safety of the hydraulic engineering constructions, operating in our country since 1971, and the first 15 years of the Federal law of the Russian Federation No. 117-FZ from 21.07.1997 “About safety of hydraulic engineering constructions”, when persons under surveillance of GTS steel of power, the industry and a water economic complex is given. The majority (97 % potentially dangerous GTS of the Russian Federation treat the IV class of solidity with service life from 40 to 50 and more years where, as a rule, is absent or the operation service, insufficient quantity of instrumentation is small. Monitoring of a technical condition of similar GTS is possible with use of the mobile, mobile complexes equipped with the modern equipment (hydrological, geophysical, geodetic, mechanical, etc.. Safety of GTS is in many respects caused by a skill level of the operational personnel. For the solution of questions of increase of their safety amending the current legislation is necessary

  9. FOREWORD: 26th IAHR Symposium on Hydraulic Machinery and Systems

    Science.gov (United States)

    Wu, Yulin; Wang, Zhengwei; Liu, Shuhong; Yuan, Shouqi; Luo, Xingqi; Wang, Fujun

    2012-11-01

    The 26th IAHR Symposium on Hydraulic Machinery and Systems, will be held in Beijing, China, 19-23 August 2012. It is jointly organized by Tsinghua University, State Key Laboratory of Hydro Science and Hydraulic Engineering, China, Jiangsu University, Xi'an University of Technology, China Agricultural University, National Engineering Research Center of Hydropower Equipment and Dongfang Electric Machinery Co., Ltd. It is the second time that China hosts such a symposium. By the end of 2011, the China electrical power system had a total of 1 050 GW installed power, out of which 220 GW was in hydropower plants. The energy produced in hydropower facilities was 662.6 TWh from a total of 4,720 TWh electrical energy production in 2011. Moreover, in 2020, new hydropower capacities are going to be developed, with a total of 180 GW installed power and an estimated 708 TWh/year energy production. And in 2011, the installed power of pumped storage stations was about 25GW. In 2020, the data will be 70GW. At the same time, the number of pumps used in China is increasing rapidly. China produces about 29,000,000 pumps with more than 220 series per year. By the end of 2011, the Chinese pumping system has a total of 950 GW installed power. The energy consumed in pumping facilities was 530 TWh in 2011. The pump energy consumption accounted for about 12% of the national electrical energy production. Therefore, there is a large market in the field of hydraulic machinery including water turbines, pump turbines and a variety of pumps in China. There are also many research projects in this field. For example, we have conducted National Key Research Projects on 1000 MW hydraulic turbine, and on the pump turbines with high head, as well as on the large capacity pumps for water supply. Tsinghua University of Beijing is proud to host the 26th IAHR Symposium on Hydraulic Machinery and Systems. Tsinghua University was established in 1911, after the founding of the People's Republic of China. It

  10. Modelling of Hydraulic Robot

    DEFF Research Database (Denmark)

    Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

    1997-01-01

    This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...... of the laws of physics on the system. The unknown (or uncertain) parameters are estimated with Maximum Likelihood (ML) parameter estimation. The identified model has been evaluated by comparing the measurements with simulation of the model. The identified model was much more capable of describing the dynamics...... of the system than the deterministic model....

  11. Hydraulic mining method

    Science.gov (United States)

    Huffman, Lester H.; Knoke, Gerald S.

    1985-08-20

    A method of hydraulically mining an underground pitched mineral vein comprising drilling a vertical borehole through the earth's lithosphere into the vein and drilling a slant borehole along the footwall of the vein to intersect the vertical borehole. Material is removed from the mineral vein by directing a high pressure water jet thereagainst. The resulting slurry of mineral fragments and water flows along the slant borehole into the lower end of the vertical borehole from where it is pumped upwardly through the vertical borehole to the surface.

  12. Spinning hydraulic jump

    Science.gov (United States)

    Abderrahmane, Hamid; Kasimov, Aslan

    2013-11-01

    We report an experimental observation of a new symmetry breaking of circular hydraulic jump into a self-organized structure that consists of a spinning polygonal jump and logarithmic-spiral waves of fluid elevation downstream. The waves are strikingly similar to spiral density waves in galaxies. The fluid flow exhibits counterparts of salient morphological features of galactic flows, in particular the outflow from the center, jets, circum-nuclear rings, gas inflows toward the galactic center, and vortices. The hydrodynamic instability revealed here may have a counterpart that plays a role in the formation and sustainability of spiral arms in galaxies.

  13. Internal hydraulics of an agricultural drainage denitrification bioreactor

    Science.gov (United States)

    Denitrification bioreactors to reduce the amount of nitrate-nitrogen in agricultural drainage are now being deployed across the U.S. Midwest. However, there are still many unknowns regarding internal hydraulic-driven processes in these "black box" engineered treatment systems. To improve this unders...

  14. HYDRAULIC CHARACTERISTICS OF CHUTE AERATORS FOR RELEASE WORKS

    Institute of Scientific and Technical Information of China (English)

    RUAN Shi-ping

    2008-01-01

    On the basis of model tests and theoretical analysis, hydraulic characteristics, air demand, air concentration distribution and their relationships between prototype and model of an aerator were studied. Some computational examples show that the present methods have higher accuracy, and can meet the need of engineering design.

  15. PROGRESS IN STUDIES ON ICE ACCUMULATION IN RIVER BENDS

    Institute of Scientific and Technical Information of China (English)

    WANG Jun; CHEN Pang-pang; SUI Jue-yi

    2011-01-01

    River ice is an important hydraulic element in temperate and polar environments and would affect hydrodynamic conditions of rivers through changes both in the boundary conditions and the thermal regime.The river bend has been reported as the common location for the initiation of ice jams because the water flow along a river bend is markedly affected by the channel curvature.In this article,the experimental studies about the ice accumulation in a river bend are reviewed.Based on experiments conducted so far,the criteria for the formation of ice jams in the river bend,the mechanisms of the ice accumulation in the river bend and the thickness profile of the ice accumulation in the river bend are discussed.The k- ε two-equation turbulence model is used to simulate the ice accumulation under an ice cover along a river bend.A formula is proposed for describing the deformation of the ice jam bottom.Our results indicate that all simulated thickness of the ice accumulation agrees reasonably well with the measured thickness of the ice accumulation in the laboratory.

  16. Relevant thermal-hydraulic aspects in the design of the RRR (Replacement Research Reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Doval, Alicia S.; Mazufri, Claudio M. [INVAP SE, Bariloche (Argentina)

    2002-07-01

    A description of the main thermal-hydraulic features and challenges of the Replacement Research Reactor, for the Australian Nuclear Science and Technology Organization (ANSTO), is presented. Different hydraulic and thermal-hydraulic aspects are considered, core cooling during full power operation and the way it affects the design, design criteria, engineered safety features and computational tools, amongst others. A special section is devoted to the thermal-hydraulic aspects inside the reflector tank, as well as the cooling of irradiation facilities, particularly, the Molybdenum production facility. (author)

  17. Chlorine-36 in Water, Snow, and Mid-Latitude Glacial Ice of North America: Meteoric and Weapons-Tests Production in the Vicinity of the Idaho National Engineering and Environmental Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    L. DeWayne; J. R. Green (USGS); S. Vogt, P. Sharma (Purdue University); S. K. Frape (University of Waterloo); S. N. Davis (University of Arizona); G. L. Cottrell (USGS)

    1999-01-01

    Measurements of chlorine-36 (36Cl) were made for 64 water, snow, and glacial-ice and -runoff samples to determine the meteoric and weapons-tests-produced concentrations and fluxes of this radionuclide at mid-latitudes in North America. The results will facilitate the use of 36Cl as a hydrogeologic tracer at the Idaho National Engineering and Environmental Laboratory (INEEL). This information was used to estimate meteoric and weapons-tests contributions of this nuclide to environmental inventories at and near the INEEL. The data presented in this report suggest a meteoric source 36Cl for environmental samples collected in southeastern Idaho and western Wyoming if the concentration is less than 1 x 10 7 atoms/L. Additionally, concentrations in water, snow, or glacial ice between 1 x 10 7 and 1 x 10 8 atoms/L may be indicative of a weapons-tests component from peak 36Cl production in the late 1950s. Chlorine-36 concentrations between 1 x 10 8 and 1 x 10 9 atoms/L may be representative of re-suspension of weapons-tests fallout airborne disposal of 36Cl from the INTEC, or evapotranspiration. It was concluded from the water, snow, and glacial data presented here that concentrations of 36Cl measured in environmental samples at the INEEL larger than 1 x 10 9 atoms/L can be attributed to waste-disposal practices.

  18. 46 CFR 28.880 - Hydraulic equipment.

    Science.gov (United States)

    2010-10-01

    ... hydraulic equipment and the adjacent work area. Protection shall be afforded to the operator of hydraulic... 46 Shipping 1 2010-10-01 2010-10-01 false Hydraulic equipment. 28.880 Section 28.880 Shipping... INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.880 Hydraulic equipment. (a) Each hydraulic system must...

  19. Final design of a free-piston hydraulic advanced Stirling conversion system

    Science.gov (United States)

    Wallace, D. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

    1991-01-01

    Under the US Department of Energy's (DOEs) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for solar distributed receiver systems. The final design is described of an engineering prototype advanced Stirling conversion system (ASCS) with a free-piston hydraulic engine output capable of delivering about 25 kW of electric power to a utility grid. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, has noncontacting bearings, and can be hermetically sealed. The ASCS is designed to deliver maximum power per year over a range of solar input with a design life of 30 years (60,000 h). The system includes a liquid Nak pool boiler heat transport system and a free-piston Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator.

  20. The numerical simulation based on CFD of hydraulic turbine pump

    Science.gov (United States)

    Duan, X. H.; Kong, F. Y.; Liu, Y. Y.; Zhao, R. J.; Hu, Q. L.

    2016-05-01

    As the functions of hydraulic turbine pump including self-adjusting and compensation with each other, it is far-reaching to analyze its internal flow by the numerical simulation based on CFD, mainly including the pressure field and the velocity field in hydraulic turbine and pump.The three-dimensional models of hydraulic turbine pump are made by Pro/Engineer software;the internal flow fields in hydraulic turbine and pump are simulated numerically by CFX ANSYS software. According to the results of the numerical simulation in design condition, the pressure field and the velocity field in hydraulic turbine and pump are analyzed respectively .The findings show that the static pressure decreases systematically and the pressure gradient is obvious in flow area of hydraulic turbine; the static pressure increases gradually in pump. The flow trace is regular in suction chamber and flume without spiral trace. However, there are irregular traces in the turbine runner channels which contrary to that in flow area of impeller. Most of traces in the flow area of draft tube are spiral.

  1. Service Cart For Engines

    Science.gov (United States)

    Ng, Gim Shek

    1995-01-01

    Cart supports rear-mounted air-cooled engine from Volkswagen or Porsche automobile. One person removes, repairs, tests, and reinstalls engine of car, van, or home-built airplane. Consists of framework of wood, steel, and aluminum components supported by four wheels. Engine lifted from vehicle by hydraulic jack and gently lowered onto waiting cart. Jack removed from under engine. Rear of vehicle raised just enough that engine can be rolled out from under it. Cart easily supports 200-lb engine. Also used to hold transmission. With removable sheet-metal top, cart used as portable seat.

  2. Service Cart For Engines

    Science.gov (United States)

    Ng, Gim Shek

    1995-01-01

    Cart supports rear-mounted air-cooled engine from Volkswagen or Porsche automobile. One person removes, repairs, tests, and reinstalls engine of car, van, or home-built airplane. Consists of framework of wood, steel, and aluminum components supported by four wheels. Engine lifted from vehicle by hydraulic jack and gently lowered onto waiting cart. Jack removed from under engine. Rear of vehicle raised just enough that engine can be rolled out from under it. Cart easily supports 200-lb engine. Also used to hold transmission. With removable sheet-metal top, cart used as portable seat.

  3. 实验教学改革与学生创新能力培养——以同济大学土木工程学院水利工程系为例%Reform of Experimental Teaching and Cultivation of Students; Innovative Ability——A Case Study of the Department of Hydraulic Engineering,College of Civil Engineering, Tongji University

    Institute of Scientific and Technical Information of China (English)

    匡翠萍; 刘曙光; 钟桂辉; 程素斌

    2012-01-01

    同济大学土木工程学院水利工程系紧密结合学校和学院的创新性实验计划与实验教学建设,经过几年的实践与改革,逐渐探索并发展出具有专业特色的实验教学方法和学生创新能力培养模式,开辟出培养专业研究型创新人才的新途径.从理论知识储备,实验教学探索与实践,创新训练计划到创新项目的指导和学生创新成果的管理,形成系列配套培养机制体系,逐步深入推进,在培养学生独立思考能力、创新管理能力和解决实际问题的能力上取得了明显的效果.%With a few years of practices and reforms, the Department of Hydraulic Engineering in Tongji University has gradually found out an appropriate pedagogical technique and applicable mode for the cultivation of the innovative ability of students based on both innovative experimental programs and experimental teaching methods in the college and the university. From theoretical knowledge accumulation, experimental teaching exploration and practice, innovative experimental program, program guidance, to achievement management, a series of corresponding systems has been established to support the training mechanism. These systems have obtained obvious achievements in the cultivation of the independent thinking, the innovative management ability and the practical problem solving ability of students.

  4. Potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets

    OpenAIRE

    Livingstone, S.J.; Clark, C. D.; Woodward, J.; Kingslake, J.

    2013-01-01

    We use the Shreve hydraulic potential equation as a simplified approach to investigate potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets. We validate the method by demonstrating its ability to recall the locations of > 60\\% of the known subglacial lakes beneath the Antarctic Ice Sheet. This is despite uncertainty in the ice-sheet bed elevation and our simplified modelling approach. However, we predict many more lakes than are ob...

  5. Hydraulic rams; a comparative investigation

    NARCIS (Netherlands)

    Tacke, J.H.P.M.

    1988-01-01

    A mathematical model describing the essential features of hydraulic ram operation is developed in order to clarify the possibilities and limitations of the ram relative to its site and its adjustments. The model distinguishes three different periods in the pumping cycle of the hydraulic ram: acceler

  6. Hydraulics. FOS: Fundamentals of Service.

    Science.gov (United States)

    John Deere Co., Moline, IL.

    This manual on hydraulics is one of a series of power mechanics texts and visual aids for training in the servicing of agricultural and industrial machinery. Focus is on oil hydraulics. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. The twelve chapters focus…

  7. 14 CFR 25.1093 - Induction system icing protection.

    Science.gov (United States)

    2010-01-01

    ... percent of maximum continuous power. (b) Turbine engines. (1) Each turbine engine must operate throughout... turbine engine must idle for 30 minutes on the ground, with the air bleed available for engine icing... between 15° and 30 °F (between −9° and −1 °C) and has a liquid water content not less than 0.3 grams...

  8. Hydraulic fracture design and optimization of gas storage wells

    Energy Technology Data Exchange (ETDEWEB)

    Mohaghegh, S.; Ameri, S. [Petroleum and Natural Gas and Engineering Department, West Virginia University, P.O. Box 6070, Morgantown, WV (United States); Balanb, B. [Schlumberger Austin Product Center, 8311 North FM 620 Road, Austin, TX (United States); Platon, V. [Baker Atlas, 10201 Westheimer Rd., Houston, TX (United States)

    1999-10-01

    Conventional hydraulic fracture design and optimization involves the use of two- or three-dimensional hydraulic fracture simulators. These simulators need a wealth of reservoir data as input to provide users with usable results. In many cases, such data are not available or very expensive to acquire. This paper provides a new methodology that can be used in cases where detail reservoir data are not available or prohibitively expensive to acquire. Through the use of two virtual intelligence techniques, namely neural networks and genetic algorithms, hydraulic fracture treatments are designed using only the available data. The unique design optimization method presented here is a logical continuation of the study that was presented in two previous papers [McVey et al., 1996, Identification of parameters influencing the response of gas storage wells to hydraulic fracturing with the aid of a neural network, SPE Computer Applications Journal, Apr., 54-57; Mohaghegh et al., 1996b, Predicting well stimulation results in a gas storage field in the absence of reservoir data, using neural networks, SPE Reservoir Engineering Journal, Nov., 54-57]. A quick review of these papers is included here. This method will use the available data on each well, which includes basic well information, production history and results of previous frac job treatments, and provides engineer with a detail optimum hydraulic fracture design unique to each well. The expected post-hydraulic fracture deliverability for the designed treatment is also provided to assist engineers in estimating incremental increase in recovery to be used in economic calculations. There are no simulated data throughout this study and all data used for development and verification of all methods are actual field data.

  9. Hydraulic Stability of Accropode Armour

    DEFF Research Database (Denmark)

    Jensen, T.; Burcharth, H. F.; Frigaard, Peter

    , and to assess the influence of core permeability on the hydraulic stability of Accropodes. Two structures were examined, one with a relatively permeable core and one with a relatively impermeable core. In November/December 1995, Ph.D.-student Marten Christensen carried out the model tests on the structure...... with permeable core (crushed granite with a gradation of 5-8 mm). The outcome of this study is described in "Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers" by Christensen & Burcharth (1995). In January/February 1996, Research Assistant Thomas Jensen carried out a similar study......The present report describes the hydraulic model tests of Accropode armour layers carried out at the Hydraulics Laboratory at Aalborg University from November 1995 through March 1996. The objective of the model tests was to investigate the hydraulic stability of Accropode armour layers...

  10. Hydraulic Stability of Accropode Armour

    DEFF Research Database (Denmark)

    Jensen, T.; Burcharth, H. F.; Frigaard, Peter

    , and to assess the influence of core permeability on the hydraulic stability of Accropodes. Two structures were examined, one with a relatively permeable core and one with a relatively impermeable core. In November/December 1995, Ph.D.-student Marten Christensen carried out the model tests on the structure...... with permeable core (crushed granite with a gradation of 5-8 mm). The outcome of this study is described in "Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers" by Christensen & Burcharth (1995). In January/February 1996, Research Assistant Thomas Jensen carried out a similar study......The present report describes the hydraulic model tests of Accropode armour layers carried out at the Hydraulics Laboratory at Aalborg University from November 1995 through March 1996. The objective of the model tests was to investigate the hydraulic stability of Accropode armour layers...

  11. Forecasting Turbine Icing Events

    DEFF Research Database (Denmark)

    Davis, Neil; Hahmann, Andrea N.; Clausen, Niels-Erik

    In this study, we present a method for forecasting icing events. The method is validated at two European wind farms in with known icing events. The icing model used was developed using current ice accretion methods, and newly developed ablation algorithms. The model is driven by inputs from the WRF...... mesoscale model, allowing for both climatological estimates of icing and short term icing forecasts. The current model was able to detect periods of icing reasonably well at the warmer site. However at the cold climate site, the model was not able to remove ice quickly enough leading to large ice...

  12. Hydraulic Yaw System

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Mørkholt, M.

    As wind turbines increase in size, combined with increased lifetime demands, new methods for load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and hereby dampen the loads to the system, which is the focus of the current paper. By utilizing...... the HAWC2 aeroelastic code and an extended model of the NREL 5MW turbine combined with a simplified linear model of the turbine, the parameters of the soft yaw system are optimized to reduce loading in critical components. Results shows that a significant reduction in fatigue and extreme loads to the yaw...... system and rotor shaft when utilizing the soft yaw drive concept compared to the original stiff yaw system. The physical demands of the hydraulic yaw system are furthermore examined for a life time of 20 years. Based on the extrapolated loads, the duty cycles show that it is possible to construct...

  13. Electro Hydraulic Hitch Control

    DEFF Research Database (Denmark)

    Hansen, M. R.; Andersen, T. O.; Nielsen, B.

    2003-01-01

    system for agricultural applications and driving for transportation. During tranport phases, the lack of suspension causes the vehicle to bounce and pitch, and makes it difficalt to control. Many systems have been proposed to cope with the oscillatory behavior, and different solutions exist. Common......This paper present and discusses R&D results on electro hydraulic hitch control for off-road vehicle, in particular active damping of oscillation occuring on tractors. The research deals with analysis and control of the oscillations occuring on tractors which are design without any susspection...... for most of the systems are that they operate on the hydrailc actuators generally providing the motive forces for moving the implement and/or attachment, typically a plough. The basic idea and physical working principle are to use the implement, moveable relative to the vehicle, as a damper mass. The paper...

  14. Using Hydraulic Network Models to Teach Electric Circuit Principles

    Science.gov (United States)

    Jones, Irvin; EERC (Engineering Education Research Center) Collaboration

    2013-11-01

    Unlike other engineering disciplines, teaching electric circuit principles is difficult for some students because there isn't a visual context to rely on. So concepts such as electric potential, current, resistance, capacitance, and inductance have little meaning outside of their definition and the derived mathematical relationships. As a work in progress, we are developing a tool to support teaching, learning, and research of electric circuits. The tool will allow the user to design, build, and operate electric circuits in the form of hydraulic networks. We believe that this system will promote greater learning of electric circuit principles by visually realizing the conceptual and abstract concepts of electric circuits. Furthermore, as a teaching and learning tool, the hydraulic network system can be used to teach and improve comprehension of electrical principles in K through 12 classrooms and in cross-disciplinary environments such as Bioengineering, Mechanical Engineering, Industrial Engineering, and Aeronautical Engineering. As a research tool, the hydraulic network can model and simulate micro/nano bio-electro-chemical systems. Organization within the Swanson School of Engineering at the University of Pittsburgh.

  15. Performance Analysis of Organic Rankine-vapor Compression Ice Maker Utilizing Food Industry Waste Heat

    National Research Council Canada - National Science Library

    Hu, Bing; Cao, Yuanshu; Ma, Weibin

    2015-01-01

    To develop the organic Rankine-vapor compression ice maker driven by food industry exhaust gases and engine cooling water, an organic Rankine-vapor compression cycle system was employed for ice making...

  16. Hydraulic conductivity of compacted zeolites.

    Science.gov (United States)

    Oren, A Hakan; Ozdamar, Tuğçe

    2013-06-01

    Hydraulic conductivities of compacted zeolites were investigated as a function of compaction water content and zeolite particle size. Initially, the compaction characteristics of zeolites were determined. The compaction test results showed that maximum dry unit weight (γ(dmax)) of fine zeolite was greater than that of granular zeolites. The γ(dmax) of compacted zeolites was between 1.01 and 1.17 Mg m(-3) and optimum water content (w(opt)) was between 38% and 53%. Regardless of zeolite particle size, compacted zeolites had low γ(dmax) and high w(opt) when compared with compacted natural soils. Then, hydraulic conductivity tests were run on compacted zeolites. The hydraulic conductivity values were within the range of 2.0 × 10(-3) cm s(-1) to 1.1 × 10(-7) cm s(-1). Hydraulic conductivity of all compacted zeolites decreased almost 50 times as the water content increased. It is noteworthy that hydraulic conductivity of compacted zeolite was strongly dependent on the zeolite particle size. The hydraulic conductivity decreased almost three orders of magnitude up to 39% fine content; then, it remained almost unchanged beyond 39%. Only one report was found in the literature on the hydraulic conductivity of compacted zeolite, which is in agreement with the findings of this study.

  17. Experimental and numerical study on ice resistance for icebreaking vessels

    Directory of Open Access Journals (Sweden)

    Hu Jian

    2015-05-01

    Full Text Available Ice resistance is defined as the time average of all longitudinal forces due to ice acting on the ship. Estimation of ship’s resistance in ice-covered waters is very important to both designers and shipbuilders since it is closely related to propulsion of a ship and it determines the engine power of the ship. Good ice performance requires ice resistance should be as low as possible to allow different manoeuvres. In this paper, different numerical methods are presented to calculate ice resistance, including semi-analytical method and empirical methods. A model test of an icebreaking vessel that was done in an ice basin has been introduced for going straight ahead in level ice at low speed. Then the comparison between model test results and numerical results are made. Some discussions and suggestions are presented as well to provide an insight into icebreaking vessel design at early stage.

  18. Thermal Diffusivity Identification of Distributed Parameter Systems to Sea Ice

    Directory of Open Access Journals (Sweden)

    Liqiong Shi

    2013-01-01

    Full Text Available A method of optimal control is presented as a numerical tool for solving the sea ice heat transfer problem governed by a parabolic partial differential equation. Taken the deviation between the calculated ice temperature and the measurements as the performance criterion, an optimal control model of distributed parameter systems with specific constraints of thermal properties of sea ice was proposed to determine the thermal diffusivity of sea ice. Based on sea ice physical processes, the parameterization of the thermal diffusivity was derived through field data. The simulation results illustrated that the identified parameterization of the thermal diffusivity is reasonably effective in sea ice thermodynamics. The direct relation between the thermal diffusivity of sea ice and ice porosity is physically significant and can considerably reduce the computational errors. The successful application of this method also explained that the optimal control model of distributed parameter systems in conjunction with the engineering background has great potential in dealing with practical problems.

  19. Great Lakes Ice Charts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Charts show ice extent and concentration three times weekly during the ice season, for all lakes except Ontario, from the 1973/74 ice season through the 2001/2002...

  20. Fiber loop ring down for static ice pressure detection

    Science.gov (United States)

    Yang, Yi; Yang, Lingzhen; Zhang, Zongwei; Yang, Jianjun; Wang, Juanfen; Zhang, Li; Deng, Xiao; Zhang, Zhaoxia

    2017-07-01

    We studied static ice pressure detection of hydraulic structures based on fiber loop ring down technology. Our detection system consists of a mode-locked laser, two 2 × 1 optical fiber couplers, a piece of single-mode fiber, the on-line micro-bend fiber sensor and a photo-detector. The static ice pressure was monitored based on measuring the change of the ring down time induced by external ice pressure on on-line micro-bend fiber sensor. We monitored the static ice pressure during ice growth and melting from -10 °C to 6 °C. The detection sensitivity is 0.00998/(μs·kPa). The proposed pressure sensing method has many advantages such as free from the fluctuation of the light power, simple structure, fast response and high sensitivity.

  1. connecting the dots between Greenland ice sheet surface melting and ice flow dynamics (Invited)

    Science.gov (United States)

    Box, J. E.; Colgan, W. T.; Fettweis, X.; Phillips, T. P.; Stober, M.

    2013-12-01

    . Because water is 'heavier' than ice, water-filled cracks have unlimited capacity to hydraulically ';jack' open fractures, penetrating, fracturing and disaggregating a solid ice body. This process promotes iceberg calving at more than 150, 1km wide marine terminating Greenland glacier fronts. Resulting from a rising trend of surface melting and sea water temperature, meltwater ejection at the underwater front of marine glaciers drives a an increasing turbulent heat exchange between the glacier front and relatively warm sea water melting it faster. Underwater melting promotes an undercutting of the glacier front leading to ice berg calving. Calving through hydrofracture or marine undercutting provide a direct and immediate ice flow speed response mechanism for surface meltwater production. Ice flow speed reacts because calving reduces flow resistance. The above physical processes interact. Cooling shuts these processes down. Negative feedbacks dampen the warming impulse. Live 21 June, 2013 is a new Danish Web site1 that exploits total mass balance rate of decline as a function of albedo to predict GRACE mass rate of change with 80% explained variance. While surface mass balance explains the mass rate of change slightly higher, surface albedo is an observable quantity as is gravity change.

  2. Hydraulic conductivity of organomodified soil

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, R.B.; Grant, J.M.; Voice, T.C.; Rakhshandehroo, G.; Xu, S.; Boyd, S.A. [Michigan State Univ., East Lansing, MI (United States)

    1995-11-01

    The effects of organomodification on soil hydraulic conductivity were investigated. Hydraulic conductivity and porosity of treated and untreated samples of a sandy loam were measured as a function of effective stress. Batch treatment with hexadecyltrimethyl ammonium (HDTMA) and dry packing produced organomodified samples that were 79% less conducive than untreated samples prior to loading. Treated samples lost less hydraulic conductivity as a result of loading than untreated samples so that treated samples had higher conductivity at high loads. Observed differences in conductivity are explained in terms of the role of the treated and untreated clay in controlling initial effective pore size and its change during consolidation.

  3. 自动脱螺纹注塑模液压马达脱螺纹与推板推出动作关系的工程分析%Engineering Analysis for Relations between Actions of Hydraulic MotorUnscrewing and Ejector Plate Ejecting in Automatic Unscrewing Injection Mould

    Institute of Scientific and Technical Information of China (English)

    畅国帏; 张凤兰

    2015-01-01

    Aiming at the problems of that the hydraulic motor unscrewing speed may not match the ejecting speed of the spring-driven ejector plate in automatic unscrewing injection mould,thus the rules of the hydraulic motor unscrewing actions were discussed,and the rules of the spring-driven ejector plate ejecting actions were also analyzed through kinematics. Through the comparison of these two kinds of rules,it comes to the conclusion that under the conditions that the low speed hydraulic motor type is mainly selected in the practical engineering application,the axial unscrewing speed of the hydraulic motor always restricts the ejecting speed of the spring-driven ejector plate,so they realize restricting synchronization. According to the conclusion,in order to avoid damage to the plastic parts thread,under the mould structure allowing conditions,low stiffness coefficient springs should be chosen in the mould for the ejector plate.%针对自动脱螺纹注塑模具中液压马达脱螺纹速度与弹簧驱动的推板推出速度可能存在不同步的问题,对液压马达脱螺纹动作规律进行了论述,对弹簧驱动的推板推出动作规律进行了运动学分析,通过对这两种动作规律的比较得出了一个结论,即在实际工程应用中选用的液压马达多为低速马达的情况下,液压马达轴向脱螺纹速度总是制约弹簧驱动的推板推出速度,从而实现了一种制约同步.根据这个结论,为避免出现塑件螺纹损坏的情况,在模具结构允许的情况下,应尽量选择劲度系数较低的推板弹簧.

  4. Analysis of groundwater flow beneath ice sheets

    Energy Technology Data Exchange (ETDEWEB)

    Boulton, G. S.; Zatsepin, S.; Maillot, B. [Univ. of Edinburgh (United Kingdom). Dept. of Geology and Geophysics

    2001-03-01

    The large-scale pattern of subglacial groundwater flow beneath European ice sheets was analysed in a previous report. It was based on a two-dimensional flowline model. In this report, the analysis is extended to three dimensions by exploring the interactions between groundwater and tunnel flow. A theory is developed which suggests that the large-scale geometry of the hydraulic system beneath an ice sheet is a coupled, self-organising system. In this system the pressure distribution along tunnels is a function of discharge derived from basal meltwater delivered to tunnels by groundwater flow, and the pressure along tunnels itself sets the base pressure which determines the geometry of catchments and flow towards the tunnel. The large-scale geometry of tunnel distribution is a product of the pattern of basal meltwater production and the transmissive properties of the bed. The tunnel discharge from the ice margin of the glacier, its seasonal fluctuation and the sedimentary characteristics of eskers are largely determined by the discharge of surface meltwater which penetrates to the bed in the terminal zone. The theory explains many of the characteristics of esker systems and can account for tunnel valleys. It is concluded that the large-scale hydraulic regime beneath ice sheets is largely a consequence of groundwater/tunnel flow interactions and that it is essential similar to non-glacial hydraulic regimes. Experimental data from an Icelandic glacier, which demonstrates measured relationships between subglacial tunnel flow and groundwater flow during the transition from summer to winter seasons for a modern glacier, and which support the general conclusions of the theory is summarised in an appendix.

  5. Influence of Icing on Bridge Cable Aerodynamics

    DEFF Research Database (Denmark)

    Koss, Holger; Frej Henningsen, Jesper; Olsen, Idar

    2013-01-01

    In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -...... forces of different bridge cables types. The experiments were conducted in a wind tunnel facility capable amongst others to simulate incloud icing conditions........ The determination of these force coefficients require a proper simulation of the ice layer occurring under the specific climatic conditions, favouring real ice accretion over simplified artificial reproduction. The work presented in this paper was performed to study the influence of ice accretion on the aerodynamic...

  6. 美国和加拿大水利工程生态调度管理研究及对中国的借鉴%Ecological Regulation of Hydraulic Engineering Projects in USA and Canada and Its Reference for China

    Institute of Scientific and Technical Information of China (English)

    唐晓燕; 曹学章; 王文林

    2013-01-01

    对美国和加拿大的水利工程生态调度管理框架和管理模式进行了系统分析.就间接(宏观)管理而言,美国和加拿大的生态调度从取水的许可证管理、保留水权的建立、水质标准、濒危物种保护和环境流量设置等方面进行管理;而在直接管理方面,主要包括对联邦水利工程的《濒危物种法》(ESA)符合性审查和非联邦水电站(5MW以上)的联邦能源管理委员会(FERC)的许可管理.通过分析中国水利工程生态调度管理中存在的问题,指出中国水利工程生态调度的体制和机制尚未有效建立,从明确生态需求、确定生态调度实施战略、加强基础研究工作以及建立和完善管理体制等方面,提出了加强中国生态调度管理的建议.在逐步建立流域生态调度管理体制的基础上,指出从生态补偿机制、参与协商机制、信息共享机制和监测反馈机制等方面建立和创新水利工程生态调度运行机制.%Systematic analysis was done of the management frameworks and models of ecological regulation of hydraulic engineering projects in USA and Canada.In terms of indirect (macro) management,the USA and Canada exercise ecological regulation through management of water licensing,establishment of reserved water rights,setting-up of water quality standards,protection of endangered species and prescription of environmental flow.However,their direct management includes mainly,ESA (Endangered Species Act) compliance review of federal hydraulic engineering projects,and licensing management of non-federal hydraulic power stations (above 5 MW) by the Federal Energy Regulatory Commission (FERC).Analysis of the problems existing in ecological regulation and management of hydraulic projects in China reveals that China has not yet had any effectively established ecological regulation management system and mechanism effectively established.lt is,hence,suggested that ecological regulation and management

  7. Hydraulic Conductivity of Residual Soil-Cement Mix

    Science.gov (United States)

    Govindasamy, P.; Taha, M. R.

    2016-07-01

    In Malaysia, although there are several researches on engineering properties of residual soils, however study on the hydraulic conductivity properties of metasedimentary residual soils is still lacking. Construction of containment walls like slurry wall techniques can be achieved with hydraulic conductivity of approximately 5 x 10-7cm/sec. The objectives of the study were to determine the physical properties of metasedimentary residual soils and to determine the influence of 1%, 3%, 5% and 10% of cement on hydraulic conductivity parameters. The coefficient of hydraulic conductivity of the soil naturally and soil-cement mixtures were determined by using the falling head test. According to the test, the hydraulic conductivity of the original soil was 4.16 x 10-8 m/s. The value decreases to 3.89 x 10-8 m/s, 2.78 x 10-8 m/s then 6.83 x 10-9 m/s with the addition of 1%, 3% and 5% of cement additives, respectively. During the hydration process, cement hydrates is formed followed by the increase in pH value and Ca(OH)2 which will alter the modification of pores size and distribution. When the quantity of cement increases, the pores size decrease. But, the addition of 10% cement gives an increased hydraulic conductivity value to 2.78 x 10-8 m/s. With 10%, the pore size increase might due to flocculation and agglomeration reaction. The generated hydraulic conductivity values will indirectly become a guide in the preliminary soil cement stabilization to modify the properties of the soil to become more like the properties of a soft rock.1. Introduction

  8. HYDRAULICS, ATHENS COUNTY, OHIO, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydrologic procedures for estimating flood discharges for a flood insurance...

  9. HYDRAULICS, JACKSON COUNTY, KENTUCKY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data include spatial datasets and data tables necessary for documenting the hydrologic procedures for estimating flood discharges for a flood insurance...

  10. HYDRAULICS, MADISON COUNTY, ALABAMA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — This Hydraulic data was reviewed and approved by FEMA during the initial MT-2 processing. Recent developments in digital terrain and geospatial database management...

  11. HYDRAULICS, HAMPDEN COUNTY, MA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulic data in this submittal include spatial datasets and model outputs necessary for computation of the 1-percent flooding extent. The minimum requirement for...

  12. Hydraulic wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-01

    The purpose of this research was to design, build and test a hydraulic wind energy system. This design used a three bladed turbine, which drove a hydraulic pump. The energy is transmitted from the pump through a long hose and into a hydraulic motor, where the energy is used. This wind system was built and tested during the winter of 1980-1981. The power train included a five meter, three bladed wind turbine, a 9.8:1 ratio gearbox, a 1.44 cubic inch displacement pump with a small supercharge gear pump attached. The hydraulic fluid was pumped through a 70', 3/4'' I-D-high pressure flexhose, then through a volume control valve and into a 1.44 cubic inch displacement motor. The fluid was returned through a 70', 1'' I-D-flexhose.

  13. 14 CFR 29.1435 - Hydraulic systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 29.1435 Section 29.1435... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each element of the hydraulic system...

  14. 14 CFR 23.1435 - Hydraulic systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 23.1435 Section 23.1435... § 23.1435 Hydraulic systems. (a) Design. Each hydraulic system must be designed as follows: (1) Each hydraulic system and its elements must withstand, without yielding, the structural loads expected...

  15. 46 CFR 28.405 - Hydraulic equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Hydraulic equipment. 28.405 Section 28.405 Shipping... Operate With More Than 16 Individuals on Board § 28.405 Hydraulic equipment. (a) Each hydraulic system... than four times the system maximum operating pressure. (c) Each hydraulic system must be equipped...

  16. Advanced Performance Hydraulic Wind Energy

    Science.gov (United States)

    Jones, Jack A.; Bruce, Allan; Lam, Adrienne S.

    2013-01-01

    The Jet Propulsion Laboratory, California Institute of Technology, has developed a novel advanced hydraulic wind energy design, which has up to 23% performance improvement over conventional wind turbine and conventional hydraulic wind energy systems with 5 m/sec winds. It also has significant cost advantages with levelized costs equal to coal (after carbon tax rebate). The design is equally applicable to tidal energy systems and has passed preliminary laboratory proof-of-performance tests, as funded by the Department of Energy.

  17. Changes in Root Hydraulic Conductivity During Wheat Evolution

    Institute of Scientific and Technical Information of China (English)

    Chang-Xing ZHAO; Xi-Ping DENG; Lun SHAN; Ernst STEUDLE; Sui-Qi ZHANG; Qing YE

    2005-01-01

    A better understanding of the mechanisms of water uptake by plant roots should be vital for improving drought resistance and water use efficiency (WUE). In the present study, we have demonstrated correlations between root system hydraulic conductivity and root characteristics during evolution using six wheat evolution genotypes (solution culture) with different ploidy chromosome sets (Triticum boeoticum Bioss., T. monococcum L.: 2n = 2x = 14; T. dicoccides Koern., T. dicoccon (Schrank) Schuebl.: 2n = 4x = 28;T. vulgare Vill., T. aestivum L. cv. Xiaoyan No. 6: 2n = 6x = 42). The experimental results showed that significant correlations were found between root system hydraulic conductivity and root characteristics of the materials with the increase in ploidy chromosomes (2x→6x) during wheat evolution. Hydraulic conductivity of the wheat root system at the whole-plant level was increased with chromosome ploidy during evolution, which was positively correlated with hydraulic conductivity of single roots, whole plant biomass,root average diameter, and root growth (length, area), whereas the root/shoot ratio had an inverse correlation with the hydraulic conductivity of root system with increasing chromosome ploidy during wheat evolution. Therefore, it is concluded that that the water uptake ability of wheat roots was strengthened from wild to modern cultivated species during evolution, which will provide scientific evidence for genetic breeding to improve the WUE of wheat by genetic engineering.

  18. Application of Curtain Grouting in Seepage Control of Hydraulic Structure Engineering%帷幕灌浆在水工建筑物防渗工程中的应用

    Institute of Scientific and Technical Information of China (English)

    边传伟; 葛志友

    2013-01-01

    结合南水北调中线干线易县段魏家坟沟排水倒虹吸工程,对帷幕灌浆技术在防渗施工中的运用及施工工艺流程进行了分析和探讨,并提出了相应的改进措施,为施工提供借鉴依据。%Combined the Yi Xian section of Weijia Fen ditch drainage inverted siphon project in with the middle route of south-to-north water diversion project,the curtain grouting technology are analyzed and discussed in seepage control of hydraulic structure construction and the application process,and proposed the corresponding improvement measures and provides the reference basis for the construction.

  19. Geomorphic Segmentation, Hydraulic Geometry, and Hydraulic Microhabitats of the Niobrara River, Nebraska - Methods and Initial Results

    Science.gov (United States)

    Alexander, Jason S.; Zelt, Ronald B.; Schaepe, Nathaniel J.

    2009-01-01

    river level. Hydraulic geometry relations indicated that local (at-a-station) channel adjustments of the Niobrara River to changing discharge are accommodated mainly by changes in velocity, and streamwise adjustments are accommodated through changes in channel width. Downstream hydraulic geometry relations are in general agreement with values previously published for rivers of the Great Plains, but coefficients are likely skewed low because the locations of the streamflow-gaging stations used in this analysis are located at natural or engineered constrictions and may not be accurately representing downstream adjustment processes of the Niobrara River. A demonstration analysis of hydraulic microhabitat attributes at a single station indicated that changes in velocity-related habitat types is the primary microhabitat adjustment over a range of discharges, but the magnitude of that adjustment for any particular discharge is temporally variable.

  20. 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...

  1. Ice Lithography for Nanodevices

    DEFF Research Database (Denmark)

    Han, Anpan; Kuan, A.; Wang, J.

    Water vapor is condensed onto a cold sample, coating it with a thin-film of ice. The ice is sensitive to electron beam lithography exposure. 10 nm ice patterns are transferred into metals by “melt-off”. Non-planar samples are coated with ice, and we pattern on cantilevers, AFM tips, and suspended...

  2. A sublimation heat engine.

    Science.gov (United States)

    Wells, Gary G; Ledesma-Aguilar, Rodrigo; McHale, Glen; Sefiane, Khellil

    2015-03-03

    Heat engines are based on the physical realization of a thermodynamic cycle, most famously the liquid-vapour Rankine cycle used for steam engines. Here we present a sublimation heat engine, which can convert temperature differences into mechanical work via the Leidenfrost effect. Through controlled experiments, quantified by a hydrodynamic model, we show that levitating dry-ice blocks rotate on hot turbine-like surfaces at a rate controlled by the turbine geometry, temperature difference and solid material properties. The rotational motion of the dry-ice loads is converted into electric power by coupling to a magnetic coil system. We extend our concept to liquid loads, generalizing the realization of the new engine to both sublimation and the instantaneous vapourization of liquids. Our results support the feasibility of low-friction in situ energy harvesting from both liquids and ices. Our concept is potentially relevant in challenging situations such as deep drilling, outer space exploration or micro-mechanical manipulation.

  3. Hydraulic fracture model comparison study: Complete results

    Energy Technology Data Exchange (ETDEWEB)

    Warpinski, N.R. [Sandia National Labs., Albuquerque, NM (United States); Abou-Sayed, I.S. [Mobil Exploration and Production Services (United States); Moschovidis, Z. [Amoco Production Co. (US); Parker, C. [CONOCO (US)

    1993-02-01

    Large quantities of natural gas exist in low permeability reservoirs throughout the US. Characteristics of these reservoirs, however, make production difficult and often economic and stimulation is required. Because of the diversity of application, hydraulic fracture design models must be able to account for widely varying rock properties, reservoir properties, in situ stresses, fracturing fluids, and proppant loads. As a result, fracture simulation has emerged as a highly complex endeavor that must be able to describe many different physical processes. The objective of this study was to develop a comparative study of hydraulic-fracture simulators in order to provide stimulation engineers with the necessary information to make rational decisions on the type of models most suited for their needs. This report compares the fracture modeling results of twelve different simulators, some of them run in different modes for eight separate design cases. Comparisons of length, width, height, net pressure, maximum width at the wellbore, average width at the wellbore, and average width in the fracture have been made, both for the final geometry and as a function of time. For the models in this study, differences in fracture length, height and width are often greater than a factor of two. In addition, several comparisons of the same model with different options show a large variability in model output depending upon the options chosen. Two comparisons were made of the same model run by different companies; in both cases the agreement was good. 41 refs., 54 figs., 83 tabs.

  4. Numerical modeling of consolidation processes in hydraulically deposited soils

    Science.gov (United States)

    Brink, Nicholas Robert

    Hydraulically deposited soils are encountered in many common engineering applications including mine tailing and geotextile tube fills, though the consolidation process for such soils is highly nonlinear and requires the use of advanced numerical techniques to provide accurate predictions. Several commercially available finite element codes poses the ability to model soil consolidation, and it was the goal of this research to assess the ability of two of these codes, ABAQUS and PLAXIS, to model the large-strain, two-dimensional consolidation processes which occur in hydraulically deposited soils. A series of one- and two-dimensionally drained rectangular models were first created to assess the limitations of ABAQUS and PLAXIS when modeling consolidation of highly compressible soils. Then, geotextile tube and TSF models were created to represent actual scenarios which might be encountered in engineering practice. Several limitations were discovered, including the existence of a minimum preconsolidation stress below which numerical solutions become unstable.

  5. Comprehensive two-dimensional river ice model based on boundary-fitted coordinate transformation method

    Directory of Open Access Journals (Sweden)

    Ze-yu MAO

    2014-01-01

    Full Text Available River ice is a natural phenomenon in cold regions, influenced by meteorology, geomorphology, and hydraulic conditions. River ice processes involve complex interactions between hydrodynamic, mechanical, and thermal processes, and they are also influenced by weather and hydrologic conditions. Because natural rivers are serpentine, with bends, narrows, and straight reaches, the commonly-used one-dimensional river ice models and two-dimensional models based on the rectangular Cartesian coordinates are incapable of simulating the physical phenomena accurately. In order to accurately simulate the complicated river geometry and overcome the difficulties of numerical simulation resulting from both complex boundaries and differences between length and width scales, a two-dimensional river ice numerical model based on a boundary-fitted coordinate transformation method was developed. The presented model considers the influence of the frazil ice accumulation under ice cover and the shape of the leading edge of ice cover during the freezing process. The model is capable of determining the velocity field, the distribution of water temperature, the concentration distribution of frazil ice, the transport of floating ice, the progression, stability, and thawing of ice cover, and the transport, accumulation, and erosion of ice under ice cover. A MacCormack scheme was used to solve the equations numerically. The model was validated with field observations from the Hequ Reach of the Yellow River. Comparison of simulation results with field data indicates that the model is capable of simulating the river ice process with high accuracy.

  6. IceT users' guide and reference.

    Energy Technology Data Exchange (ETDEWEB)

    Moreland, Kenneth D.

    2011-01-01

    The Image Composition Engine for Tiles (IceT) is a high-performance sort-last parallel rendering library. In addition to providing accelerated rendering for a standard display, IceT provides the unique ability to generate images for tiled displays. The overall resolution of the display may be several times larger than any viewport that may be rendered by a single machine. This document is an overview of the user interface to IceT.

  7. IceT users' guide and reference.

    Energy Technology Data Exchange (ETDEWEB)

    Moreland, Kenneth D.

    2009-06-01

    The Image Composition Engine for Tiles (IceT) is a high-performance sort-last parallel rendering library. In addition to providing accelerated rendering for a standard display, IceT provides the unique ability to generate images for tiled displays. The overall resolution of the display may be several times larger than any viewport that may be rendered by a single machine. This document is an overview of the user interface to IceT.

  8. Wave-Ice interaction

    Institute of Scientific and Technical Information of China (English)

    沈奚海莉

    2001-01-01

    The growth and movement of sea ice cover are influenced by the presence of wave field. Inturn, the wave field is influenced by the presence of ice cover. Their interaction is not fully understood.In this paper, we discuss some current understanding on wave attenuation when it propagates through frag-mented ice cover, ice drift due to the wave motion, and the growth characteristics of ice cover in wave field.

  9. 解析水文频率在水利工程设计中的作用%Analysis on the Effect of Hydrological Frequency in Hydraulic Engineering Design

    Institute of Scientific and Technical Information of China (English)

    石高扬; 包波; 郑晓波

    2014-01-01

    As an important infrastructure, the effect of water conservancy engineering in agricultural irrigation, power gen-eration, city water supply, flood control is remarkable. Water c-onservancy engineering design relates to the subsequent const-ruction cost, operation ef iciency, and hydrological frequency analysis provides the condition for engineering design parame-ters set ing.%作为重要的基础设施,水利工程在农业灌溉、发电、城市供水、防洪等方面作用显著。水利工程设计关乎后续施工建设成本、运行效率,而水文频率的分析为工程设计参数确立提供了条件。

  10. Dynamic Ice-Water Interactions Form Europa's Chaos Terrains

    Science.gov (United States)

    Blankenship, D. D.; Schmidt, B. E.; Patterson, G. W.; Schenk, P.

    2011-12-01

    Unique to the surface of Europa, chaos terrain is diagnostic of the properties and dynamics of its icy shell. We present a new model that suggests large melt lenses form within the shell and that water-ice interactions above and within these lenses drive the production of chaos. This model is consistent with key observations of chaos, predicts observables for future missions, and indicates that the surface is likely still active today[1]. We apply lessons from ice-water interaction in the terrestrial cryosphere to hypothesize a dynamic lense-collapse model to for Europa's chaos terrain. Chaos terrain morphology, like that of Conamara chaos and Thera Macula, suggests a four-phase formation [1]: 1) Surface deflection occurs as ice melts over ascending thermal plumes, as regularly occurs on Earth as subglacial volcanoes activate. The same process can occur at Europa if thermal plumes cause pressure melt as they cross ice-impurity eutectics. 2) Resulting hydraulic gradients and driving forces produce a sealed, pressurized melt lense, akin to the hydraulic sealing of subglacial caldera lakes. On Europa, the water cannot escape the lense due to the horizontally continuous ice shell. 3) Extension of the brittle ice lid above the lense opens cracks, allowing for the ice to be hydrofractured by pressurized water. Fracture, brine injection and percolation within the ice and possible iceberg toppling produces ice-melange-like granular matrix material. 4) Refreezing of the melt lense and brine-filled pores and cracks within the matrix results in raised chaos. Brine soaking and injection concentrates the ice in brines and adds water volume to the shell. As this englacial water freezes, the now water-filled ice will expand, not unlike the process of forming pingos and other "expansion ice" phenomena on Earth. The refreezing can raise the surface and create the oft-observed matrix "domes" In this presentation, we describe how catastrophic ice-water interactions on Earth have

  11. Anti-icing Behavior of Thermally Sprayed Polymer Coatings

    Science.gov (United States)

    Koivuluoto, Heli; Stenroos, Christian; Kylmälahti, Mikko; Apostol, Marian; Kiilakoski, Jarkko; Vuoristo, Petri

    2017-01-01

    Surface engineering shows an increasing potential to provide a sustainable approach to icing problems. Currently, several passive anti-ice properties adoptable to coatings are known, but further research is required to proceed for practical applications. This is due to the fact that icing reduces safety, operational tempo, productivity and reliability of logistics, industry and infrastructure. An icing wind tunnel and a centrifugal ice adhesion test equipment can be used to evaluate and develop anti-icing and icephobic coatings for a potential use in various arctic environments, e.g., in wind power generation, oil drilling, mining and logistic industries. The present study deals with evaluation of icing properties of flame-sprayed polyethylene (PE)-based polymer coatings. In the laboratory-scale icing tests, thermally sprayed polymer coatings showed low ice adhesion compared with metals such as aluminum and stainless steel. The ice adhesion strength of the flame-sprayed PE coating was found to have approximately seven times lower ice adhesion values compared with metallic aluminum, indicating a very promising anti-icing behavior.

  12. Anti-icing Behavior of Thermally Sprayed Polymer Coatings

    Science.gov (United States)

    Koivuluoto, Heli; Stenroos, Christian; Kylmälahti, Mikko; Apostol, Marian; Kiilakoski, Jarkko; Vuoristo, Petri

    2016-12-01

    Surface engineering shows an increasing potential to provide a sustainable approach to icing problems. Currently, several passive anti-ice properties adoptable to coatings are known, but further research is required to proceed for practical applications. This is due to the fact that icing reduces safety, operational tempo, productivity and reliability of logistics, industry and infrastructure. An icing wind tunnel and a centrifugal ice adhesion test equipment can be used to evaluate and develop anti-icing and icephobic coatings for a potential use in various arctic environments, e.g., in wind power generation, oil drilling, mining and logistic industries. The present study deals with evaluation of icing properties of flame-sprayed polyethylene (PE)-based polymer coatings. In the laboratory-scale icing tests, thermally sprayed polymer coatings showed low ice adhesion compared with metals such as aluminum and stainless steel. The ice adhesion strength of the flame-sprayed PE coating was found to have approximately seven times lower ice adhesion values compared with metallic aluminum, indicating a very promising anti-icing behavior.

  13. Servo Controlled Variable Pressure Modification to Space Shuttle Hydraulic Pump

    Science.gov (United States)

    Kouns, H. H.

    1983-01-01

    Engineering drawings show modifications made to the constant pressure control of the model AP27V-7 hydraulic pump to an electrically controlled variable pressure setting compensator. A hanger position indicator was included for continuously monitoring hanger angle. A simplex servo driver was furnished for controlling the pressure setting servovalve. Calibration of the rotary variable displacement transducer is described as well as pump performance and response characteristics.

  14. Micromechanical Aspects of Hydraulic Fracturing Processes

    Science.gov (United States)

    Galindo-torres, S. A.; Behraftar, S.; Scheuermann, A.; Li, L.; Williams, D.

    2014-12-01

    A micromechanical model is developed to simulate the hydraulic fracturing process. The model comprises two key components. Firstly, the solid matrix, assumed as a rock mass with pre-fabricated cracks, is represented by an array of bonded particles simulated by the Discrete Element Model (DEM)[1]. The interaction is ruled by the spheropolyhedra method, which was introduced by the authors previously and has been shown to realistically represent many of the features found in fracturing and communition processes. The second component is the fluid, which is modelled by the Lattice Boltzmann Method (LBM). It was recently coupled with the spheropolyhedra by the authors and validated. An advantage of this coupled LBM-DEM model is the control of many of the parameters of the fracturing fluid, such as its viscosity and the injection rate. To the best of the authors' knowledge this is the first application of such a coupled scheme for studying hydraulic fracturing[2]. In this first implementation, results are presented for a two-dimensional situation. Fig. 1 shows one snapshot of the LBM-DEM coupled simulation for the hydraulic fracturing where the elements with broken bonds can be identified and the fracture geometry quantified. The simulation involves a variation of the underground stress, particularly the difference between the two principal components of the stress tensor, to explore the effect on the fracture path. A second study focuses on the fluid viscosity to examine the effect of the time scales of different injection plans on the fracture geometry. The developed tool and the presented results have important implications for future studies of the hydraulic fracturing process and technology. references 1. Galindo-Torres, S.A., et al., Breaking processes in three-dimensional bonded granular materials with general shapes. Computer Physics Communications, 2012. 183(2): p. 266-277. 2. Galindo-Torres, S.A., A coupled Discrete Element Lattice Boltzmann Method for the

  15. HYDRAULIC CONCRETE COMPOSITION AND PROPERTIES CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    O. M. Pshinko

    2015-08-01

    Full Text Available Purpose. Scientific work aims at the development and testing of information system to meet the challenges of concrete composition design and control (for railway structures and buildings based on the physico-analytical method algorithm for hydraulic concrete composition calculation. Methodology. The proposed algorithm of hydraulic concrete composition calculation is based on the physicochemical mechanics and in particular on the rheology of elastic–viscous–plastic bodies. The system of canonical equations consists of the equations for concrete strength, absolute volume, concrete mix consistency as well as the equation for optimal concrete saturation with aggregates while minimizing cement content. The joint solution of these four equations related to composition allows determining for the materials the concrete composition of required strength, concrete workability with minimum cement content. The procedure for calculation of hydraulic concrete composition according to the physico-analytical method consists of two parts: 1 physical, which is laboratory testing of concrete mix components in different concrete compositions; 2 analytical, which represents the calculation algorithm for concrete compositions equivalent in concrete strength and workability that comply with the specific conditions of concrete placing. Findings. To solve the problem of designing the concrete composition with the desired properties for railway structures and buildings it was proposed to use the information technology in the form of a developed computer program whose algorithm includes the physico-analytical method for hydraulic concrete composition determination. Originality. The developed concrete composition design method takes into account the basic properties of raw materials, concrete mix and concrete, which are pre-determined. The distinctive feature of physico-analytical method is obtaining of a set of equivalent compositions with a certain concrete mix

  16. Fundamental Ice Crystal Accretion Physics Studies

    Science.gov (United States)

    Struk, Peter M.; Broeren, Andy P.; Tsao, Jen-Ching; Vargas, Mario; Wright, William B.; Currie, Tom; Knezevici, Danny; Fuleki, Dan

    2012-01-01

    Due to numerous engine power-loss events associated with high-altitude convective weather, ice accretion within an engine due to ice crystal ingestion is being investigated. The National Aeronautics and Space Administration (NASA) and the National Research Council (NRC) of Canada are starting to examine the physical mechanisms of ice accretion on surfaces exposed to ice-crystal and mixed-phase conditions. In November 2010, two weeks of testing occurred at the NRC Research Altitude Facility utilizing a single wedge-type airfoil designed to facilitate fundamental studies while retaining critical features of a compressor stator blade or guide vane. The airfoil was placed in the NRC cascade wind tunnel for both aerodynamic and icing tests. Aerodynamic testing showed excellent agreement compared with CFD data on the icing pressure surface and allowed calculation of heat transfer coefficients at various airfoil locations. Icing tests were performed at Mach numbers of 0.2 to 0.3, total pressures from 93 to 45 kPa, and total temperatures from 5 to 15 C. Ice and liquid water contents ranged up to 20 and 3 g/m3, respectively. The ice appeared well adhered to the surface in the lowest pressure tests (45 kPa) and, in a particular case, showed continuous leading-edge ice growth to a thickness greater than 15 mm in 3 min. Such widespread deposits were not observed in the highest pressure tests, where the accretions were limited to a small area around the leading edge. The suction surface was typically ice-free in the tests at high pressure, but not at low pressure. The icing behavior at high and low pressure appeared to be correlated with the wet-bulb temperature, which was estimated to be above 0 C in tests at 93 kPa and below 0 C in tests at lower pressure, the latter enhanced by more evaporative cooling of water. The authors believe that the large ice accretions observed in the low pressure tests would undoubtedly cause the aerodynamic performance of a compressor component

  17. SIMULATION OF FLUID FLOW IN CHANNEL OF A NOVEL HYDRAULIC SHOCK GENERATOR

    Institute of Scientific and Technical Information of China (English)

    Fu Xin; Yang Huayong

    2000-01-01

    In order to improve the engineering performance of a novel hydraulic shock generator,the fluid flow inside its complex passages is numerically investigated.The effects of the inlet flow velocity upon the turbulence intensity of the jet flow are analyzed.The calculated pressure loss is experimentally verified with the consideration of temperature determined viscosity shifting.The results are used as the reference in the further development of the hydraulic shock generator

  18. The Development of an Optimal Control Strategy for a Series Hydraulic Hybrid Vehicle

    Directory of Open Access Journals (Sweden)

    Chih-Wei Hung

    2016-03-01

    Full Text Available In this work, a Truck Class II series hydraulic hybrid model is established. Dynamic Programming (DP methodology is applied to derive the optimal power-splitting factor for the hybrid system for preselected driving schedules. Implementable rules are derived by extracting the optimal trajectory features from a DP scheme. The system behaviors illustrate that the improved control strategy gives a highly effective operation region for the engine and high power density characteristics for the hydraulic components.

  19. 14 CFR 121.283 - Induction system ice prevention.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Induction system ice prevention. 121.283 Section 121.283 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Induction system ice prevention. A means for preventing the malfunctioning of each engine due to...

  20. Arctic ice islands

    Energy Technology Data Exchange (ETDEWEB)

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  1. Method for use of hydraulically or electrically controlled solenoids under failed on conditions

    Science.gov (United States)

    Bolenbaugh, Jonathan M.; Naqi, Syed

    2014-07-08

    A method to operate a clutch device in an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and at least one electric machine includes, in response to a failure condition detected within a flow control device configured to facilitate flow of hydraulic fluid for operating the clutch device, selectively preventing the flow of hydraulic fluid from entering the flow control device and feeding the clutch device. Synchronization of the clutch device is initiated when the clutch device is intended for activation, and only if the clutch device is synchronized, the flow of hydraulic fluid is selectively permitted to enter the flow control device to activate the clutch device.

  2. MECHATRONICS SYSTEM ENGINEERING FOR

    DEFF Research Database (Denmark)

    Conrad, Finn; Roli, Francesco

    2005-01-01

    rotary vane actuator for robot manipulators is presented. The contribution proposes mathematical modelling, control and simulation of a novel water hydraulic rotary vane actuator applied to power and control a three-links manipulator. The results include engineering design and test of the proposed...

  3. MECHATRONICS SYSTEM ENGINEERING FOR

    DEFF Research Database (Denmark)

    Conrad, Finn; Roli, Francesco

    2005-01-01

    rotary vane actuator for robot manipulators is presented. The contribution proposes mathematical modelling, control and simulation of a novel water hydraulic rotary vane actuator applied to power and control a three-links manipulator. The results include engineering design and test of the proposed...

  4. Fieldwork Coastal Engineering 2014

    NARCIS (Netherlands)

    De Boer, G.G.; Schlepers, M.H.; Aggarwal, A.; Willemsen, G.; Rip, J.; Jansma, J.; Jansen, L.J.M.; Rafiq, S.W.; Postma, M.G.; Palaiogianni, N.; Hanssen, J.L.J.; Loozen, M.M.; Van den Bosch, B.A.P.; Fotis, G.; De Louw, R.M.J.G.; Meijerink, E.

    2014-01-01

    This report is the final part of the course CIE5318 Fieldwork Hydraulic Engineering at the TU Delft. In this course a group of international students from the TU Delft a and the Varna Free University visit the coast of the Black Sea. During their weeks visit they do field research in Varna, Bulgaria

  5. Fieldwork Coastal Engineering 2015

    NARCIS (Netherlands)

    Alkusa, M.A.; Bruijn, W.E.L.; Disberg, C.; Drouen, N.A.T.; Van Duijn, D.F.; Fragkopoulos, T.; Hábetler, Z.; Haug, D.C.; Julianus, E.J.B.; Kibarov, V.; Kostadinova, D.; Leenders, S.; Lyubimova, T.V.; Naumov, D.; Rajabalinejad, R.; Peters, J.H.J.; Pronker, J.S.; Voycheva, N.; Van der Wiel, R.J.; Van Zelst, V.T.M.

    2016-01-01

    Since 2003 there is a cooperation between the Hydraulic Engineering department of Delft University of Technology and Bulgarian universities. The cooperation focusses on exchange of knowledge and the development of the coast in the area of Varna. Dutch and Bulgarian students get the possibility to

  6. Development and application of robots for checking and repairing civil engineering facilities in hydraulic power plants. Suiryoku hatsudensho doboku setsubi wo taisho to shita kakushu tenken hoshu robot no kaihatsu to tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T.; Hibino, Y. (The Tokyo Electric Power Co. Inc., Tokyo (Japan))

    1993-07-25

    Development efforts are being made on robots to improve efficiency in the checking and repairing works that require a great amount of labor at hydraulic power plants. This paper introduces examples of the development and application of these robots. An underwater remotely controlled robot developed based on unmanned submarine boats mounts TV cameras, dives to a depth of 300 meters, and checks underwater structures under control from above the ground. A self-driven waterway investigating system mounting an underground radar equipment investigates tunnel covers and rear cavities, and can acquire continuous data for the cover thickness and cavities without a need of boring. The following robots have obtained satisfactory results in efficiency improvement and accuracy: an unmanned robot for checking inside of a waterway tunnel with small cross section difficult for a man to enter (using a video camera); a video photographing robot to photograph large underground cavities such as surge tanks; and a self-driven robot to visually inspect and photograph steel pipes and measure their thickness. 8 figs., 8 tabs.

  7. Numerical simulation on a throttle governing system with hydraulic butterfly valves in a marine environment

    Science.gov (United States)

    Wan, Hui-Xiong; Fang, Jun; Huang, Hui

    2010-12-01

    Hydraulic butterfly valves have been widely applied in marine engineering because of their large switching torque, low pressure loss and suitability for large and medium diameter pipelines. Due to control problems resulting from switching angular speeds of the hydraulic butterfly valve, a throttle-governing control mode has been widely adopted, and detailed analysis has been carried out worldwide on the structural principle concerning speed-regulation and the load torque on the shaft while opening or closing a hydraulic butterfly valve. However relevant reports have yet been published on the change law, the error and the influencing factors of the rotational angular velocity of the hydraulic butterfly valve while opening and closing. In this article, research was based on some common specifications of a hydraulic butterfly valve with a symmetrical valve flap existing in a marine environment. The throttle governing system supplied by the accumulator to achieve the switching of the hydraulic control valve was adopted, and the mathematical models of the system were established in the actual conditions while the numerical simulations took place. The simulation results and analysis show that the rotational angular velocity and the error of the hydraulic butterfly valve while switching is influenced greatly by the drainage amount of the accumulator, resulting in pressure loss in the pipeline, the temperature of hydraulic medium and the load of the hydraulic butterfly valve. The simulation results and analysis provide a theoretical basis for the choice of the total capacity of the accumulator and pipeline diameters in a throttle governing system with a hydraulic butterfly valve. It also determines the type and specification of the hydraulic butterfly valve and the design of motion parameters of the transported fluid.

  8. Complex Fluids and Hydraulic Fracturing.

    Science.gov (United States)

    Barbati, Alexander C; Desroches, Jean; Robisson, Agathe; McKinley, Gareth H

    2016-06-07

    Nearly 70 years old, hydraulic fracturing is a core technique for stimulating hydrocarbon production in a majority of oil and gas reservoirs. Complex fluids are implemented in nearly every step of the fracturing process, most significantly to generate and sustain fractures and transport and distribute proppant particles during and following fluid injection. An extremely wide range of complex fluids are used: naturally occurring polysaccharide and synthetic polymer solutions, aqueous physical and chemical gels, organic gels, micellar surfactant solutions, emulsions, and foams. These fluids are loaded over a wide range of concentrations with particles of varying sizes and aspect ratios and are subjected to extreme mechanical and environmental conditions. We describe the settings of hydraulic fracturing (framed by geology), fracturing mechanics and physics, and the critical role that non-Newtonian fluid dynamics and complex fluids play in the hydraulic fracturing process.

  9. Hydraulic properties of ladle slags

    Directory of Open Access Journals (Sweden)

    J. Vlček

    2016-07-01

    Full Text Available The article presents results of examining of hydraulic properties of ladle slags formed during production of steel. The studied ladle slags were subjected to different cooling mode from the molten state. Based on the ability of the slag react with the water was assessed their hydraulic activity. The hydraulic properties are caused by the presence of minerals dicalcium silicate, tricalcium aluminate, mayenite, brownmillerite and dicalcium ferite. The emergence of required hydrating phases in the ladle slags is conditioned by a sufficient CaO content and their cooling rate. The contact the slag with water during processing and their ageing has a negative effect. The experiment has shown that the phase transformation of the mineral dicalcium silicate which occurs during cooling of the ladle slags cause their volume instability.

  10. 振动压路机液压系统研究%On the Hydraulic Driving System Based on Full Hydraulic Vibratory Roller

    Institute of Scientific and Technical Information of China (English)

    杨平; 许炳照

    2011-01-01

    According to the application of hydraulic control technology of full hydraulic vibratory roller,the paper presents a design scheme of how to select hydraulic driving pumps and the rotators for the hydraulic component parts.Before selecting the methods of the hydraulic driving pumps and the rotators,the design scheme of the hydraulic system power and the engine should be mated properly,so as to determine the data of full hydraulic vibratory roller.%对全液压振动压路机的液压系统进行配置设计,在确定液压泵及液压马达型号规格后,计算液压系统功率与整机的功率合理匹配,从而确定全液压振动压路机各液压系统的参数,完成整机液压系统的合理配置。

  11. Analysis and discussion of different methods of artificial ice-high specimen preparation

    Institute of Scientific and Technical Information of China (English)

    ShuJuan Zhang; Wei Ma; ZhiZhong Sun; HaiMin Du

    2014-01-01

    Because ice-high foundation soil is widely distributed in permafrost regions, the correct preparation of ice-high specimens is of critical interest in engineering design for foundation stability. Past research has shown that the uniaxial compression strength of ice-high frozen soils changes as the ice or total water content increases;the differences of different methods of specimen preparation are analyzed here and the advantages and disadvantages of them are presented. It is confirmed that the role of crushed ice is significantly different from that of naturally frozen ice in frozen soils, and the size and amount of crushed ice will influence the strength and deformation mechanism of frozen soils. Therefore, it is strongly recommended that when a ice-high specimen is artificially prepared, the ice should be frozen through natural means and not be replaced with crushed ice.

  12. Proceedings, fifth international congress, International Association of Engineering Geology

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    4 volumes containing papers presented at a conference on geologic engineering. Subjects discussed include the following: engineering geological investigations of rock masses for civil engineering projects and mining operations; engineering geological problems related to foundations and excavations in weak rocks; engineering geological aspects of foundations in soils; engineering geological problems related to hydraulic and hydroelectric developments; engineering geology in the development of road, railroad, coastal and offshore projects; engineering geological aspects in environment planning and urban areas. Relevant papers are abstracted separately.

  13. Hydraulic resistance of biofilms

    KAUST Repository

    Dreszer, C.

    2013-02-01

    Biofilms may interfere with membrane performance in at least three ways: (i) increase of the transmembrane pressure drop, (ii) increase of feed channel (feed-concentrate) pressure drop, and (iii) increase of transmembrane passage. Given the relevance of biofouling, it is surprising how few data exist about the hydraulic resistance of biofilms that may affect the transmembrane pressure drop and membrane passage. In this study, biofilms were generated in a lab scale cross flow microfiltration system at two fluxes (20 and 100Lm-2h-1) and constant cross flow (0.1ms-1). As a nutrient source, acetate was added (1.0mgL-1 acetate C) besides a control without nutrient supply. A microfiltration (MF) membrane was chosen because the MF membrane resistance is very low compared to the expected biofilm resistance and, thus, biofilm resistance can be determined accurately. Transmembrane pressure drop was monitored. As biofilm parameters, thickness, total cell number, TOC, and extracellular polymeric substances (EPS) were determined, it was demonstrated that no internal membrane fouling occurred and that the fouling layer actually consisted of a grown biofilm and was not a filter cake of accumulated bacterial cells. At 20Lm-2h-1 flux with a nutrient dosage of 1mgL-1 acetate C, the resistance after 4 days reached a value of 6×1012m-1. At 100Lm-2h-1 flux under the same conditions, the resistance was 5×1013m-1. No correlation of biofilm resistance to biofilm thickness was found; Biofilms with similar thickness could have different resistance depending on the applied flux. The cell number in biofilms was between 4×107 and 5×108 cellscm-2. At this number, bacterial cells make up less than a half percent of the overall biofilm volume and therefore did not hamper the water flow through the biofilm significantly. A flux of 100Lm-2h-1 with nutrient supply caused higher cell numbers, more biomass, and higher biofilm resistance than a flux of 20Lm-2h-1. However, the biofilm thickness

  14. Top Sounder Ice Penetration

    Science.gov (United States)

    Porter, D. L.; Goemmer, S. A.; Sweeney, J. H.

    2014-12-01

    Ice draft measurements are made as part of normal operations for all US Navy submarines operating in the Arctic Ocean. The submarine ice draft data are unique in providing high resolution measurements over long transects of the ice covered ocean. The data has been used to document a multidecadal drop in ice thickness, and for validating and improving numerical sea-ice models. A submarine upward-looking sonar draft measurement is made by a sonar transducer mounted in the sail or deck of the submarine. An acoustic beam is transmitted upward through the water column, reflecting off the bottom of the sea ice and returning to the transducer. Ice thickness is estimated as the difference between the ship's depth (measured by pressure) and the acoustic range to the bottom of the ice estimated from the travel time of the sonar pulse. Digital recording systems can provide the return off the water-ice interface as well as returns that have penetrated the ice. Typically, only the first return from the ice hull is analyzed. Information regarding ice flow interstitial layers provides ice age information and may possibly be derived with the entire return signal. The approach being investigated is similar to that used in measuring bottom sediment layers and will involve measuring the echo level from the first interface, solving the reflection loss from that transmission, and employing reflection loss versus impedance mismatch to ascertain ice structure information.

  15. Two-Mode Operation Engine Mount Design for Automotive Applications

    OpenAIRE

    Reza Tikani; Nader Vahdati; Saeed Ziaei-Rad

    2012-01-01

    Hydraulic engine mounts are applied to the automotive applications to isolate the chassis from the high frequency noise and vibration generated by the engine as well as to limit the engine shake motions resulting at low frequencies. In this paper, a new hydraulic engine mount with a controllable inertia track profile is proposed and its dynamic behavior is investigated. The profile of the inertia track is varied by applying a controlled force to a cylindrical rubber disk, placed in the inerti...

  16. Controls of Hydraulic Wind Turbine

    Directory of Open Access Journals (Sweden)

    Zhang Yin

    2016-01-01

    Full Text Available In this paper a hydraulic wind turbine generator system was proposed based on analysis the current wind turbines technologies. The construction and principles were introduced. The mathematical model was verified using MATLAB and AMsim. A displacement closed loop of swash plate of motor and a speed closed loop of generator were setup, a PID control is introduced to maintain a constant speed and fixed frequency at wind turbine generator. Simulation and experiment demonstrated that the system can connect grid to generate electric and enhance reliability. The control system demonstrates a high performance speed regulation and effectiveness. The results are great significant to design a new type hydraulic wind turbine system.

  17. Ross Ice Shelf, Antarctic Ice and Clouds

    Science.gov (United States)

    1991-01-01

    In this view of Antarctic ice and clouds, (56.5S, 152.0W), the Ross Ice Shelf of Antarctica is almost totally clear, showing stress cracks in the ice surface caused by wind and tidal drift. Clouds on the eastern edge of the picture are associated with an Antarctic cyclone. Winds stirred up these storms have been known to reach hurricane force.

  18. Direct observations of evolving subglacial drainage beneath the Greenland Ice Sheet.

    Science.gov (United States)

    Andrews, Lauren C; Catania, Ginny A; Hoffman, Matthew J; Gulley, Jason D; Lüthi, Martin P; Ryser, Claudia; Hawley, Robert L; Neumann, Thomas A

    2014-10-02

    Seasonal acceleration of the Greenland Ice Sheet is influenced by the dynamic response of the subglacial hydrologic system to variability in meltwater delivery to the bed via crevasses and moulins (vertical conduits connecting supraglacial water to the bed of the ice sheet). As the melt season progresses, the subglacial hydrologic system drains supraglacial meltwater more efficiently, decreasing basal water pressure and moderating the ice velocity response to surface melting. However, limited direct observations of subglacial water pressure mean that the spatiotemporal evolution of the subglacial hydrologic system remains poorly understood. Here we show that ice velocity is well correlated with moulin hydraulic head but is out of phase with that of nearby (0.3-2 kilometres away) boreholes, indicating that moulins connect to an efficient, channelized component of the subglacial hydrologic system, which exerts the primary control on diurnal and multi-day changes in ice velocity. Our simultaneous measurements of moulin and borehole hydraulic head and ice velocity in the Paakitsoq region of western Greenland show that decreasing trends in ice velocity during the latter part of the melt season cannot be explained by changes in the ability of moulin-connected channels to convey supraglacial melt. Instead, these observations suggest that decreasing late-season ice velocity may be caused by changes in connectivity in unchannelized regions of the subglacial hydrologic system. Understanding this spatiotemporal variability in subglacial pressures is increasingly important because melt-season dynamics affect ice velocity beyond the conclusion of the melt season.

  19. Integrating hydraulic equivalent sections into a hydraulic geometry study

    Science.gov (United States)

    Jia, Yanhong; Yi, Yujun; Li, Zhiwei; Wang, Zhaoyin; Zheng, Xiangmin

    2017-09-01

    Hydraulic geometry (HG) is an important geomorphic concept that has played an indispensable role in hydrological analyses, physical studies of streams, ecosystem and aquatic habitat studies, and sedimentology research. More than 60 years after Leopold and Maddock (1953) first introduced the concept of HG, researchers have still not uncovered the physical principles underlying HG behavior. One impediment is the complexity of the natural river cross section. The current study presents a new way to simplify the cross section, namely, the hydraulic equivalent section, which is generalized from the cross section in the ;gradually varied flow of an alluvial river; (GVFAR) and features hydrodynamic properties and bed-building laws similar to those of the GVFAR. Energy balance was used to derive the stage Z-discharge Q relationship in the GVFAR. The GVFAR in the Songhua River and the Yangtze River were selected as examples. The data, including measured discharge, river width, water stage, water depth, wet area, and cross section, were collected from the hydrological yearbooks of typical hydrological stations on the Songhua River and the Yangtze River from 1955 to 1987. The relationships between stage Z-discharge Q and cross-sectional area A-stage Z at various stations were analyzed, and ;at-a-station hydraulic geometry; (AHG) relationships were obtained in power-law forms. Based on derived results and observational data analysis, the Z-Q and Z-A relationships of AHG were similar to rectangular weir flows, thus the cross section of the GVFAR was generalized as a compound rectangular, hydraulic equivalent cross section. As to bed-building characteristics, the bankfull discharge method and the stage-discharge-relation method were used to calculate the dominant variables of the alluvial river. This hydraulic equivalent section has the same Z-Q relation, Z-A relation, dominant discharge, dominant river width, and dominant water depth as the cross section in the GVFAR. With the

  20. The ultimate bearing capacity of ice beams

    Directory of Open Access Journals (Sweden)

    Li Liang

    2013-02-01

    Full Text Available It is usually proposed that bearing capacity of the ice beam during its interaction with a sloping hydraulic structure is exhausted when tensile stresses in the beam’s cross-section reach some limit. But besides the tensile stress there is a compressive stress during the interaction with a sloping structure. This can change our estimations of the ultimate bearing capacity and load exerted on the structure. The purpose of the study was to estimate influence of the longitudinal compressive stress on the ice beam’s ultimate bearing capacity. The solution was obtained with the program complex LS-DYNA. Results of the mathematical modeling were compared with data of physical experiments conducted by Sodhi. Good correlation of the results gave possibility to conduct wide numerical experiments and to suggest corrections to the existing methodology.

  1. Ice Engineering: Ice Jams, Winter 2002-2003

    Science.gov (United States)

    2004-07-01

    freezeup jams occurring in January. On 21 January, the National Weather Service reported a long freezeup jam on the Allegheny River that extended from... freezeup jam. Another freezeup jam, reported on 24 January, extended from Brady’s Bend up the Allegheny River about five miles to Hillville. This...large freezeup jam was still in place on 28 January (NWS 2003d). Again on 28 January, another freezeup jam was reported from Reno north for two miles

  2. Hydraulic Hybrid Propulsion for Heavy Vehicles: Combining the Simulation and Engine-In-the-Loop Techniques to Maximize the Fuel Economy and Emission Benefits Propulsion hybride hydraulique des poids lourds : une approche alliant les techniques de simulation et d’« Engine-In-the-loop » (EIL afin de maximiser les économies de carburant et les avantages en termes d’émissions

    Directory of Open Access Journals (Sweden)

    Filipi Z.

    2009-09-01

    Full Text Available The global energy situation, the dependence of the transportation sector on fossil fuels, and a need for a rapid response to the global warming challenge, provide a strong impetus for development of fuel efficient vehicle propulsion. The task is particularly challenging in the case of trucks due to severe weight/size constraints. Hybridization is the only approach offering significant breakthroughs in near and mid-term. In particular, the series configuration decouples the engine from the wheels and allows full flexibility in controlling the engine operation, while the hydraulic energy conversion and storage provides exceptional power density and efficiency. The challenge stems from a relatively low energy density of the hydraulic accumulator. This places particular emphasis on development of the supervisory controller. The conventional wisdom is to operate the engine at the “sweet spot”, but the aggressive pursuit of engine efficiency as the sole objective can lead to frequent and rapid diesel engine transients, thus causing an adverse affect on the soot emissions and driver feel. Therefore, we propose a comprehensive methodology for considering a combined hybrid system fuel-economy and emissions objective. The fuel economy is addressed with the simulation-based approach, while investigating the impact of engine transients on particulate emission relies on the Engine-In-the-loop (EIL capability. The EIL study confirms advantages of a modulated state-of-charge control over the thermostatic approach, and demonstrates the ability of the Series Hydraulic Hybrid to improve the fuel economy of the medium truck by 72%, while reducing the particulate emission by 74% compared to the conventional baseline over the city driving schedule. La situation énergétique mondiale, la dépendance du secteur des transports vis-à-vis des combustibles d’origine fossile et la nécessité d’une réponse rapide face au défi présenté par le r

  3. DCS Hydraulics Submittal, Butler County, Alabama, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

  4. DCS Hydraulics Submittal, Bullock County, Alabama, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

  5. DCS Hydraulics Submittal, Covington County, Alabama, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydraulics data includes spatial datasets and data tables necessary for documenting the hydraulic procedures for computing flood elevations for a flood insurance...

  6. 基于 ANP 及熵权法的国际水利工程项目市场开发阶段风险决策%ANP and Entropy Metod-Based Risk Decision System for International Hydraulic Engineering in Macket Development Phaee

    Institute of Scientific and Technical Information of China (English)

    章恒全; 缪朦朦

    2015-01-01

    为帮助国际水利工程承包商在市场开发阶段面临多个项目时进行有效的风险决策,通过梳理国际水利工程特点,提炼项目风险决策关键影响因素,同时考虑各项决策因素之间的紧密关联性,选用网络层次分析法(ANP)构建了多层次的市场开发阶段风险决策模型,进而依序构建了无权重超矩阵、权重超矩阵及极限超矩阵,实现了ANP模型主观权重求解。引入熵值法修正了ANP法的主观性,利用距离函数将主客观权重集成,得到了各项指标的综合决策权重。以S公司拟从 P1、P2、P3三个项目之一进行项目决策为例进行计算,结果表明该风险决策模型为承包商提供了一种科学的项目选择方法。%The study aims to help the international hydraulic engineering contractors to make an effective risk decision w hen facing multiple choices in the market development stage .By analyzing the characteristics of international hydraulic engineering ,and studying the key factors of risk decision and their close correlation ,a multi-level risk decision model was built by ANP method ,and the subject weight of ANP model was solved .Then the entropy value method was used to correct the subjectivity of the ANP method and the distance function was used to achieve the integration of subjective and objective weights ,thus obtaining the comprehensive weights of different indexes .Finally ,the model was used to help S company to make decision among the three projects P1 ,P2 ,P3 .T he result show s that the risk decision model provides a scientific selection method for contractors .

  7. High Pressure Hydraulic Distribution System

    Science.gov (United States)

    1991-05-20

    to 500 0 F. 5 cycles. 5000 F room temperature to 50001F; 45 ______________ Icycles The tesis planned for the distribution system demonstrator were...American Society for Testing and Materials ASTM D412 - Tension Testing of Vulcanized Rubber ASTM D571 - Testing Automotive Hydraulic Brake Hose Society of

  8. Hydraulic fracturing system and method

    Energy Technology Data Exchange (ETDEWEB)

    Ciezobka, Jordan; Salehi, Iraj

    2017-02-28

    A hydraulic fracturing system and method for enhancing effective permeability of earth formations to increase hydrocarbon production, enhance operation efficiency by reducing fluid entry friction due to tortuosity and perforation, and to open perforations that are either unopened or not effective using traditional techniques, by varying a pump rate and/or a flow rate to a wellbore.

  9. Hydraulic jumps in a channel

    DEFF Research Database (Denmark)

    Bonn, D.; Andersen, Anders Peter; Bohr, Tomas

    2009-01-01

    We present a study of hydraulic jumps with flow predominantly in one direction, created either by confining the flow to a narrow channel with parallel walls or by providing an inflow in the form of a narrow sheet. In the channel flow, we find a linear height profile upstream of the jump as expected...

  10. Hydraulic Fracture Containment in Sand

    NARCIS (Netherlands)

    Dong, Y.

    2010-01-01

    The mechanism of hydraulic fracturing in soft, high permeability material is considered fundamentally different from that in hard, low permeability rock, where a tensile fracture is created and conventional linear elastic fracture mechanics (LEFM) applies. The fracturing and associated modeling work

  11. Design of hydraulic recuperation unit

    Directory of Open Access Journals (Sweden)

    Jandourek Pavel

    2016-01-01

    Full Text Available This article deals with design and measurement of hydraulic recuperation unit. Recuperation unit consist of radial turbine and axial pump, which are coupled on the same shaft. Speed of shaft with impellers are 6000 1/min. For economic reasons, is design of recuperation unit performed using commercially manufactured propellers.

  12. Tree Hydraulics: How Sap Rises

    Science.gov (United States)

    Denny, Mark

    2012-01-01

    Trees transport water from roots to crown--a height that can exceed 100 m. The physics of tree hydraulics can be conveyed with simple fluid dynamics based upon the Hagen-Poiseuille equation and Murray's law. Here the conduit structure is modelled as conical pipes and as branching pipes. The force required to lift sap is generated mostly by…

  13. Tree Hydraulics: How Sap Rises

    Science.gov (United States)

    Denny, Mark

    2012-01-01

    Trees transport water from roots to crown--a height that can exceed 100 m. The physics of tree hydraulics can be conveyed with simple fluid dynamics based upon the Hagen-Poiseuille equation and Murray's law. Here the conduit structure is modelled as conical pipes and as branching pipes. The force required to lift sap is generated mostly by…

  14. Charging valve of the full hydraulic braking system

    Directory of Open Access Journals (Sweden)

    Jinshi Chen

    2016-03-01

    Full Text Available It is known that the full hydraulic braking system has excellent braking performance. As the key component of the full hydraulic braking system, the parameters of the accumulator charging valve have a significant effect on the braking performance. In this article, the key parameters of the charging valve are analyzed through the static theoretical and an Advanced Modeling Environment for performing Simulation of engineering systems (AMESim simulation model of the dual-circuit accumulator charging valve is established based on the real structure parameters first. Second, according to the results of the dynamic simulation, the dynamic characteristics of the charging pressure, the flow rate, and the frequency of the charging valve are studied. The key parameters affecting the serial production are proposed and some technical advices for improving the performance of the full hydraulic system are provided. Finally, the theoretical analysis is validated by the simulation results. The comparison between the simulation results and the experimental results indicates that the simulated AMESim model of the charging valve is accurate and credible with the error rate inside 0.5% compared with the experimental result. Hence, the performance of the charging valve meets the request of the full hydraulic braking system exactly.

  15. Simulation and control of an electro-hydraulic actuated clutch

    Science.gov (United States)

    Balau, Andreea-Elena; Caruntu, Constantin-Florin; Lazar, Corneliu

    2011-08-01

    The basic function of any type of automotive transmission is to transfer the engine torque to the vehicle with the desired ratio smoothly and efficiently and the most common control devices inside the transmission are clutches and hydraulic pistons. The automatic control of the clutch engagement plays a crucial role in Automatic Manual Transmission (AMT) vehicles, being seen as an increasingly important enabling technology for the automotive industry. It has a major role in automatic gear shifting and traction control for improved safety, drivability and comfort and, at the same time, for fuel economy. In this paper, a model for a wet clutch actuated by an electro-hydraulic valve used by Volkswagen for automatic transmissions is presented. Starting from the developed model, a simulator was implemented in Matlab/Simulink and the model was validated against data obtained from a test-bench provided by Continental Automotive Romania, which includes the Volkswagen wet clutch actuated by the electro-hydraulic valve. Then, a predictive control strategy is applied to the model of the electro-hydraulic actuated clutch with the aims of controlling the clutch piston displacement and decreasing the influence of the network-induced delays on the control performances. The simulation results obtained with the proposed method are compared with the ones obtained with different networked controllers and it is shown that the strategy proposed in this paper can indeed improve the performances of the control system.

  16. A new linear type hydraulic motor

    Science.gov (United States)

    Jiang, Dong; Zhang, Tong; Li, Wenhua; Chen, Xinyang

    2017-08-01

    This paper proposes the design of liner type hydraulic motor on the base of inner curved radial piston hydraulic motor. The hydraulic cylinders of the new type motor are in the straight line which will improve the utilization of the axial space and different out power can be supplied by changes the number of cylinders. In this paper, the structure and working principle of the liner type hydraulic motor is introduced.

  17. Energy-Efficient Systems Eliminate Icing Danger for UAVs

    Science.gov (United States)

    2010-01-01

    Ames Research Center engineer Leonard Haslim invented an anti-icing t echnology called an electroexpulsive separation system, which uses m echanical force to shatter potentially dangerous ice buildup on an ai rcraft surface. Temecula, California-based Ice Management Systems (no w known as IMS-ESS) licensed the technology from Ames and has discov ered a niche market for the lightweight, energy-efficient technology: unmanned aerial vehicles (UAVs). IMS-ESS systems now prevent damagi ng ice accumulation on military UAVs, allowing the vehicles to carry out crucial missions year round.

  18. In-flight photogrammetric measurement of wing ice accretions

    Science.gov (United States)

    Mcknight, R. C.; Palko, R. L.; Humes, R. L.

    1986-01-01

    A photographic instrumentation system was developed for the Lewis icing research aircraft to measure wind ice accretions during flight. The system generates stereo photographs of the accretions which are then photogrammetrically measured by the Air Force Arnold Engineering and Development Center. The measurements yield a survey of spatial coordinates of an accretion's surface to an accuracy of at least + or - 0.08 cm. The accretions can then be matched to corresponding icing cloud and aerodynamic measurements. The system is being used to measure rime, mixed, and clear natural ice accretions.

  19. Hydraulic characterization of " Furcraea andina

    Science.gov (United States)

    Rivera-Velasquez, M. F.; Fallico, C.; Molinari, A.; Santillan, P.; Salazar, M.

    2012-04-01

    The present level of pollution, increasingly involving groundwaters, constitutes a serious risk for environment and human health. Therefore the remediation of saturated and unsaturated soils, removing pollutant materials through innovative and economic bio-remediation techniques is more frequently required. Recent studies on natural fiber development have shown the effectiveness of these fibers for removal of some heavy metals, due to the lignin content in the natural fibers which plays an important role in the adsorption of metal cations (Lee et al., 2004; Troisi et al., 2008; C. Fallico, 2010). In the context of remediation techniques for unsaturated and/or saturated zone, an experimental approach for the hydraulic characterization of the "Furcraea andina" (i.e., Cabuya Blanca) fiber was carried out. This fiber is native to Andean regions and grows easily in wild or cultivated form in the valleys and hillsides of Colombia, Ecuador, and Peru. Fibers of "Furcraea andina" were characterized by experimental tests to determine their hydraulic conductivity or permeability and porosity in order to use this medium for bioremediation of contaminated aquifer exploiting the physical, chemical and microbial capacity of natural fiber in heavy metal adsorption. To evaluate empirically the hydraulic conductivity, laboratory tests were carried out at constant head specifically on the fibers manually extracted. For these tests we used a flow cell (used as permeameter), containing the "Furcraea andina" fibers to be characterized, suitably connected by a tygon pipe to a Marriott's bottle, which had a plastic tube that allow the adjustment of the hydraulic head for different tests to a constant value. By this experiment it was also possible to identify relationships that enable the estimation of permeability as a function of density, i.e. of the compaction degree of the fibers. Our study was carried out for three values of hydraulic head (H), namely 10, 18, and 25 cm and for each

  20. 14 CFR 25.1435 - Hydraulic systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 25.1435 Section 25.1435... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1435 Hydraulic systems. (a) Element design. Each element of the hydraulic system must be designed to: (1) Withstand the proof...

  1. 14 CFR 27.1435 - Hydraulic systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hydraulic systems. 27.1435 Section 27.1435... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1435 Hydraulic systems. (a) Design. Each hydraulic system and its elements must withstand, without yielding, any structural loads...

  2. IOMASA SEA ICE DEVELOPMENTS

    DEFF Research Database (Denmark)

    Andersen, Søren; Tonboe, Rasmus; Heygster, Georg

    2005-01-01

    Sensitivity studies show that the radiometer ice concentration estimate can be biased by +10% by anomalous atmospheric emissivity and -20% by anomalous ice surface emissivity. The aim of the sea ice activities in EU 5th FP project IOMASA is to improve sea ice concentration estimates at higher...... spatial resolution. The project is in the process of facilitating an ice concentration observing system through validation and a better understanding of the microwave radiative transfer of the sea ice and overlying snow layers. By use of a novel modelling approach, it is possible to better detect...... and determine the circumstances that may lead to anomalous sea ice concentration retrieval as well as to assess and possibly minimize the sensitivities of the retrieval system. Through an active partnership with the SAF on Ocean and Sea Ice, a prototype system will be implemented as an experimental product...

  3. Dead-ice environments

    DEFF Research Database (Denmark)

    2010-01-01

    Kötlujökull transports considerable amounts of supraglacial debris at its snout because of frontal oscillations with frequent ice advances followed by ice-margin stagnation. Kötlujökull provides suitable conditions of studying dead-ice melting and landscape formation in a debris-charged lowland...... glacier environment. The scientific challenges are to answer the key questions. What are the conditions for dead-ice formation? From which sources does the sediment cover originate? Which melting and reworking processes act in the ice-cored moraines? What is the rate of de-icing in the ice-cored moraines...... and conclusions on dead-ice melting and landscape formation from Kötlujökull. Processes and landform-sediment associations are linked to the current climate and glacier–volcano interaction....

  4. IOMASA SEA ICE DEVELOPMENTS

    DEFF Research Database (Denmark)

    Andersen, Søren; Tonboe, Rasmus; Heygster, Georg

    2005-01-01

    Sensitivity studies show that the radiometer ice concentration estimate can be biased by +10% by anomalous atmospheric emissivity and -20% by anomalous ice surface emissivity. The aim of the sea ice activities in EU 5th FP project IOMASA is to improve sea ice concentration estimates at higher...... spatial resolution. The project is in the process of facilitating an ice concentration observing system through validation and a better understanding of the microwave radiative transfer of the sea ice and overlying snow layers. By use of a novel modelling approach, it is possible to better detect...... and determine the circumstances that may lead to anomalous sea ice concentration retrieval as well as to assess and possibly minimize the sensitivities of the retrieval system. Through an active partnership with the SAF on Ocean and Sea Ice, a prototype system will be implemented as an experimental product...

  5. Forecast Icing Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Forecast Icing Product (FIP) is an automatically-generated index suitable for depicting areas of potentially hazardous airframe icing. The FIP algorithm uses...

  6. Current Icing Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Current Icing Product (CIP) is an automatically-generated index suitable for depicting areas of potentially hazardous airframe icing. The CIP algorithm combines...

  7. Ice Adhesion Testing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Uses Evaluate and compare the relative performance of materials and surfcae coating based on their ability to aid in ice removal Test the effectiveness of de-icing...

  8. Ice Cream Headaches

    Science.gov (United States)

    Diseases and Conditions Ice cream headaches By Mayo Clinic Staff Ice cream headaches are brief, stabbing headaches that can happen when you eat, drink or inhale something cold. Digging into an ice cream cone is a common trigger, but eating or ...

  9. Islands in the ice

    DEFF Research Database (Denmark)

    Jørgensen, Tina; Kjær, Kurt H.; Haile, James Seymour

    2012-01-01

    Nunataks are isolated bedrocks protruding through ice sheets. They vary in age, but represent island environments in 'oceans' of ice through which organism dispersals and replacements can be studied over time. The J.A.D. Jensen's Nunataks at the southern Greenland ice sheet are the most isolated ...

  10. Facility for testing ice drills

    Science.gov (United States)

    Nielson, Dennis L.; Delahunty, Chris; Goodge, John W.; Severinghaus, Jeffery P.

    2017-05-01

    The Rapid Access Ice Drill (RAID) is designed for subsurface scientific investigations in Antarctica. Its objectives are to drill rapidly through ice, to core samples of the transition zone and bedrock, and to leave behind a borehole observatory. These objectives required the engineering and fabrication of an entirely new drilling system that included a modified mining-style coring rig, a unique fluid circulation system, a rod skid, a power unit, and a workshop with areas for the storage of supplies and consumables. An important milestone in fabrication of the RAID was the construction of a North American Test (NAT) facility where we were able to test drilling and fluid processing functions in an environment that is as close as possible to that expected in Antarctica. Our criteria for site selection was that the area should be cold during the winter months, be located in an area of low heat flow, and be at relatively high elevation. We selected a site for the facility near Bear Lake, Utah, USA. The general design of the NAT well (NAT-1) started with a 27.3 cm (10.75 in.) outer casing cemented in a 152 m deep hole. Within that casing, we hung a 14 cm (5.5 in.) casing string, and, within that casing, a column of ice was formed. The annulus between the 14 and 27.3 cm casings provided the path for circulation of a refrigerant. After in-depth study, we chose to use liquid CO2 to cool the hole. In order to minimize the likelihood of the casing splitting due to the volume increase associated with freezing water, the hole was first cooled and then ice was formed in increments from the bottom upward. First, ice cubes were placed in the inner liner and then water was added. Using this method, a column of ice was incrementally prepared for drilling tests. The drilling tests successfully demonstrated the functioning of the RAID system. Reproducing such a facility for testing of other ice drilling systems could be advantageous to other research programs in the future.

  11. Developing a Water Well for the Ice Backfilling of DYE-2.

    Science.gov (United States)

    1982-12-01

    Greenland ice sheet program. Phase 1: Casing operation. CRREL Special Report 80-24. Russell, F.L. (1965) Water production in polar ice cap by utilization...the snow until the vertical advance is intercepted by impermeable ice , where the meltwater ponds. After enough has accumulated in the hole, the...AD-Ai25 583 DEVELOPING A W~ATER WELL FOR THE ICE BACKFILLING OF / DYE-2(U) COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH J RAND DEC 82 CRREL

  12. Indian River Inlet: An Evaluation by the Committee on Tidal Hydraulics

    Science.gov (United States)

    1994-07-01

    Bay Tidal Ranges and Inlet Velocities lipient Maxmkum Veedty csea -seeuenad Am Tikdl Range Keulegan WIlMZ Year aq ft ft fpsf 1950 6,690 0.71 3.1 3.2 1960...34 Journal of the Hydraulics Division, American Society of Civil Engineers, HY 11. Ariathurai, R., MacArthur, R. C., and Krone, R. B. (1977...and Arulalandan, K. (1978). "Erosion rates of cohesive soils," Journal of the Hydraulics Division, American Society of Civil Engineers, HY 2, 279

  13. Horizontal roof gap of backfill hydraulic support

    Institute of Scientific and Technical Information of China (English)

    张强; 张吉雄; 邰阳; 方坤; 殷伟

    2015-01-01

    For the backfill hydraulic support as the key equipment for achieving integration of backfilling and coal mining simultaneously in the practical process, its characteristics will directly influence the backfill body’s compression ratio. Horizontal roof gap, as a key parameter of backfilling characteristics, may impact the backfilling effect from the aspects of control of roof subsidence in advance, support stress, backfilling process and the support design. Firstly, the reason why horizontal roof gap exists was analyzed and its definition, causes and connotation were introduced, then adopting the Pro/E 3D simulation software, three typical 3D entity models of backfill hydraulic supports were built, based on the influence of horizontal roof gap on backfilling effect, and influence rules of four factors, i.e. support height, suspension height, suspension angle and tamping angle, were emphatically analyzed on horizontal roof gap. The results indicate that, the four factors all have significant impacts on horizontal roof gap, but show differences in influence trend and degree, showing negative linear correlation, positive linear correlation, positive semi-parabolic correlation and negative semi-parabolic correlation, respectively. Four legs type is the most adaptive to the four factors, while six legs (II) type has the poorest adaptability, and the horizontal roof gap is small under large support height, small suspension height, small suspension angle and large tamping angle situation. By means of optimizing structure components and their positional relation and suspension height of backfill scrape conveyor in the process of support design and through controlling working face deployment, roof subsidence in advance, mining height and backfilling during engineering application, the horizontal roof gap is optimized. The research results can be served as theoretical basis for support design and guidance for backfill support to have better performance in backfilling.

  14. Thermal Hydraulic Performance of Tight Lattice Bundle

    Science.gov (United States)

    Yamamoto, Yasushi; Akiba, Miyuki; Morooka, Shinichi; Shirakawa, Kenetsu; Abe, Nobuaki

    Recently, the reduced moderation spectrum BWR has been studied. The fast neutron spectrum is obtained through triangular tight lattice fuel. However, there are few thermal hydraulic test data and thermal hydraulic correlation applicable to critical power prediction in such a tight lattice bundle. This study aims to enhance the database of the thermal hydraulic performance of the tight lattice bundle whose rod gap is about 1mm. Therefore, thermal hydraulic performance measurement tests of tight lattice bundles for the critical power, the pressure drop and the counter current flow limiting were performed. Moreover, the correlations to evaluate the thermal-hydraulic performance of the tight lattice bundle were developed.

  15. Development, Implementation, and Pilot Evaluation of a Model-Driven Envelope Protection System to Mitigate the Hazard of In-Flight Ice Contamination on a Twin-Engine Commuter Aircraft

    Science.gov (United States)

    Martos, Borja; Ranaudo, Richard; Norton, Billy; Gingras, David; Barnhart, Billy

    2014-01-01

    Fatal loss-of-control accidents have been directly related to in-flight airframe icing. The prototype system presented in this report directly addresses the need for real-time onboard envelope protection in icing conditions. The combination of prior information and real-time aerodynamic parameter estimations are shown to provide sufficient information for determining safe limits of the flight envelope during inflight icing encounters. The Icing Contamination Envelope Protection (ICEPro) system was designed and implemented to identify degradations in airplane performance and flying qualities resulting from ice contamination and provide safe flight-envelope cues to the pilot. The utility of the ICEPro system for mitigating a potentially hazardous icing condition was evaluated by 29 pilots using the NASA Ice Contamination Effects Flight Training Device. Results showed that real time assessment cues were effective in reducing the number of potentially hazardous upset events and in lessening exposure to loss of control following an incipient upset condition. Pilot workload with the added ICEPro displays was not measurably affected, but pilot opinion surveys showed that real time cueing greatly improved their awareness of a hazardous aircraft state. The performance of ICEPro system was further evaluated by various levels of sensor noise and atmospheric turbulence.

  16. Evaluation of Hydraulic Response of the Wave Dragon

    DEFF Research Database (Denmark)

    Frigaard, Peter; Kofoed, Jens Peter

    The present study investigates the hydraulic response of the wave energy converter Wave Dragon. This is done by peforming model tests in a wave tank in the Hydraulics & Coastal Engineering Laboratory at Aalborg University. In the model tests a floating scale model (length scale 1:50) of the Wave...... Dragon is subjected to irregular, long crested irregular and short crested sea conditions corresponding to typical situations under which the Wave Dragon will produce power. Furthermore two situations corresponding to extreme storm conditions are tested. The objective of the study is to determine...... the wave induced forces in the moorings and in the junction between the reflectors and the reservoir part, and motions of the Wave Dragon situated in different sea conditions....

  17. Evaluation of Hydraulic Response of the Wave Dragon

    DEFF Research Database (Denmark)

    Frigaard, Peter; Kofoed, Jens Peter

    The present study investigates the hydraulic response of the wave energy converter Wave Dragon. This is done by peforming model tests in a wave tank in the Hydraulics & Coastal Engineering Laboratory at Aalborg University. In the model tests a floating scale model (length scale 1:50) of the Wave...... Dragon is subjected to irregular, long crested irregular and short crested sea conditions corresponding to typical situations under which the Wave Dragon will produce power. Furthermore two situations corresponding to extreme storm conditions are tested. The objective of the study is to determine...... the wave induced forces in the moorings and in the junction between the reflectors and the reservoir part, and motions of the Wave Dragon situated in different sea conditions....

  18. EFFECT OF AERATOR ON HYDRAULIC DRAG ACTING ON A CHUTE

    Institute of Scientific and Technical Information of China (English)

    NI Han-gen; LI Xin; ZHOU Jing; JIN Qiao

    2005-01-01

    The formulae used to calculate the friction in the non-uniform flow chute were examined with the experimental data, and the results show that the accuracy of the formula is enough for engineering applications. A comparison between the results of friction respectively from the uniform flow assumption and the non-uniform flow approximation indicates that the former is an order of magnitude larger than the latter in the case of steep chute. The hydraulic drag on a steep chute with aerators was measured on the hydraulic model directly and the coefficient of the aerator effect on the drag was obtained. The variation patterns of the wall shear just downstream of the aerators were investigated and the mechanism of the increase in the drag by aerator were analyzed qualitatively with the measured water-depths just downstream the aerators.

  19. A New Type of Hydraulic Actuator Using Electrorheological Fluids

    Science.gov (United States)

    Wendt, Eckhard; Büsing, Klaus W.

    Electrorheological Fluids (ERF) are usually used in semi active damping elements, e.g. shock absorbers or engine mounts because of their continuously controllable shear stress. A totally new field of application may be achieved, if an ERF is used as a hydraulic fluid and not only as a control medium. In this case a fundamental need is the capability to produce a volume flow by using normal hydraulic pumps, e.g. gear pumps. The ERF and the hydraulic components both must have a long lifetime without unusual wear. Bayer AG has developed an ERF based on soft crosslinked PU-particles dispersed in silicone oil. These ERF are characterised by a low basic viscosity, a high ER-effect and a moderate conductivity. Compared with previous ERF where hard inorganic particles were used, the new fluid is not abrasive. It is foremostly this characteristic which gives the possibility of using the ERF in hydraulic systems with high shear rates and high shear stresses. The usage of ERF as hydraulic fluid allows the construction of proportional valves without mechanically driven parts. The control of the pressure drop over the valves is realised directly by an electrical signal. It is possible to realise actuators with very fast response times since the reaction time of ERF is within milliseconds. For demonstration purpose Bayer AG has built an actuator which is controlled by an electrorheological valve-block. The calculation of the dimension of this actuator and the valves will be shown and the realised response time will be demonstrated.

  20. Review on hidden trouble detection and health diagnosis of hydraulic concrete structures

    Institute of Scientific and Technical Information of China (English)

    WU; ZhongRu; LI; Ji; GU; ChongShi; SU; HuaiZhi

    2007-01-01

    A large number of hydraulic concrete structures have hidden defects such as cracks,erosion,freeze and thaw,thermal fatigue,carbonization.These hidden defects seriously affect the strength,stability and durability of structures.These problems are studied mainly by single monitoring or diagnosis methods at present.The integration of multiple monitoring and diagnosis methods is not applied widely.Besides,the analysis theory on these problems is not developed very well.The systemic study on the aging mechanism of hydraulic concrete structures,timevariation model and health diagnosis is still not enough.The support for engineering practice is limited.Aimed at these major scientific and technological problems and combined with specific projects,study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out.This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures,seepage detection,the construction of in-situ sensing system,the combination of field detection and in-situ monitoring,the mechanism of crack,freeze and thaw,erosion and carbonization of hydraulic concrete structure,mechanism of combination aging; time-variation model of hydraulic concrete structure,theories and methods for health diagnosis of hydraulic concrete structures.

  1. An Initial Study of the Fundamentals of Ice Crystal Icing Physics in the NASA Propulsion Systems Laboratory

    Science.gov (United States)

    Struk, Peter M.; Ratvasky, Thomas P.; Bencic, Timothy J.; Van Zante, Judith F.; King, Michael C.; Tsao, Jen-Ching; Bartkus, Tadas P.

    2017-01-01

    This paper presents results from an initial study of the fundamental physics of ice-crystal ice accretion using the NASA Propulsion Systems Lab (PSL). Ice accretion due to the ingestion of ice-crystals is being attributed to numerous jet-engine power-loss events. The NASA PSL is an altitude jet-engine test facility which has recently added a capability to inject ice particles into the flow. NASA is evaluating whether this facility, in addition to full-engine and motor-driven-rig tests, can be used for more fundamental ice-accretion studies that simulate the different mixed-phase icing conditions along the core flow passage of a turbo-fan engine compressor. The data from such fundamental accretion tests will be used to help develop and validate models of the accretion process. The present study utilized a NACA0012 airfoil. The mixed-phase conditions were generated by partially freezing the liquid-water droplets ejected from the spray bars. This paper presents data regarding (1) the freeze out characteristics of the cloud, (2) changes in aerothermal conditions due to the presence of the cloud, and (3) the ice accretion characteristics observed on the airfoil model. The primary variable in this test was the PSL plenum humidity which was systematically varied for two duct-exit-plane velocities (85 and 135 ms) as well as two particle size clouds (15 and 50 m MVDi). The observed clouds ranged from fully glaciated to fully liquid, where the liquid clouds were at least partially supercooled. The air total temperature decreased at the test section when the cloud was activated due to evaporation. The ice accretions observed ranged from sharp arrow-like accretions, characteristic of ice-crystal erosion, to cases with double-horn shapes, characteristic of supercooled water accretions.

  2. Arctic ice management

    Science.gov (United States)

    Desch, Steven J.; Smith, Nathan; Groppi, Christopher; Vargas, Perry; Jackson, Rebecca; Kalyaan, Anusha; Nguyen, Peter; Probst, Luke; Rubin, Mark E.; Singleton, Heather; Spacek, Alexander; Truitt, Amanda; Zaw, Pye Pye; Hartnett, Hilairy E.

    2017-01-01

    As the Earth's climate has changed, Arctic sea ice extent has decreased drastically. It is likely that the late-summer Arctic will be ice-free as soon as the 2030s. This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean. It is unlikely that CO2 levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative. Here we investigate a means for enhancing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface, where it will freeze more rapidly. We show that where appropriate devices are employed, it is possible to increase ice thickness above natural levels, by about 1 m over the course of the winter. We examine the effects this has in the Arctic climate, concluding that deployment over 10% of the Arctic, especially where ice survival is marginal, could more than reverse current trends of ice loss in the Arctic, using existing industrial capacity. We propose that winter ice thickening by wind-powered pumps be considered and assessed as part of a multipronged strategy for restoring sea ice and arresting the strongest feedbacks in the climate system.

  3. Hydraulic fracture during epithelial stretching

    Science.gov (United States)

    Casares, Laura; Vincent, Romaric; Zalvidea, Dobryna; Campillo, Noelia; Navajas, Daniel; Arroyo, Marino; Trepat, Xavier

    2015-03-01

    The origin of fracture in epithelial cell sheets subject to stretch is commonly attributed to excess tension in the cells’ cytoskeleton, in the plasma membrane, or in cell-cell contacts. Here, we demonstrate that for a variety of synthetic and physiological hydrogel substrates the formation of epithelial cracks is caused by tissue stretching independently of epithelial tension. We show that the origin of the cracks is hydraulic; they result from a transient pressure build-up in the substrate during stretch and compression manoeuvres. After pressure equilibration, cracks heal readily through actomyosin-dependent mechanisms. The observed phenomenology is captured by the theory of poroelasticity, which predicts the size and healing dynamics of epithelial cracks as a function of the stiffness, geometry and composition of the hydrogel substrate. Our findings demonstrate that epithelial integrity is determined in a tension-independent manner by the coupling between tissue stretching and matrix hydraulics.

  4. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions....... On page 590 of this issue, MacGregor et al. (2) estimate the mean rates of snow accumulation and ice flow of the Greenland Ice Sheet over the past 9000 years based on an ice sheet-wide dated radar stratigraphy (3). They show that the present changes of the Greenland Ice Sheet are partly an ongoing...... response to the last deglaciation. The results help to clarify how sensitive the ice sheet is to climate changes....

  5. Forecasting Turbine Icing Events

    DEFF Research Database (Denmark)

    Davis, Neil; Hahmann, Andrea N.; Clausen, Niels-Erik;

    2012-01-01

    is not shut down for its protection. We also found that there is a a large spread across the various turbines within a wind park, in the amount of icing. This is currently not taken into account by our model. Evaluating and adding these small scale differences to the model will be undertaken as future work....... accumulations, which have not been seen in observations. In addition to the model evaluation we were able to investigate the potential occurrence of ice induced power loss at two wind parks in Europe using observed data. We found that the potential loss during an icing event is large even when the turbine......In this study, we present a method for forecasting icing events. The method is validated at two European wind farms in with known icing events. The icing model used was developed using current ice accretion methods, and newly developed ablation algorithms. The model is driven by inputs from the WRF...

  6. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt

    2016-01-01

    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions....... On page 590 of this issue, MacGregor et al. (2) estimate the mean rates of snow accumulation and ice flow of the Greenland Ice Sheet over the past 9000 years based on an ice sheet-wide dated radar stratigraphy (3). They show that the present changes of the Greenland Ice Sheet are partly an ongoing...... response to the last deglaciation. The results help to clarify how sensitive the ice sheet is to climate changes....

  7. Bio-based Hydraulic Fluids

    Science.gov (United States)

    2008-04-17

    currently formulated with vegetable oils (i.e., rapeseed , sun flower, corn, soybean, canola, coconut, etc.) and synthetic ester, such as polyol ester...2008 Vegetable Oil • Excellent lubrication • Nontoxic • Biodegradable • Derived from renewable resources such as rapeseed , sunflower, corn...Mineral Oil 100 SAE 15W-40 G Rapeseed 32 Commercial HF H Polyol ester 22 MIL-PRF-32073 Grade 2 I Canola - Cooking Oil *Hydraulic fluid 3717 April

  8. Fire Resistant Aircraft Hydraulic System.

    Science.gov (United States)

    1982-07-01

    and compounds based on new experimental elastomers as well as most commercially available elastomers were screened in seeking seals that were both...for hydraulic component testing. All of the available E6.5 stock was purchased for the screening tests. However, DuPont stated that other homologs of...with the lubricity and anti-wear additive olyvan A (molybdenum oxysulphide dithiocarbamate ) added in the quantity of less than one percent by weight

  9. Icing Operations - De-Icing Policy

    Directory of Open Access Journals (Sweden)

    Jaromír Procházka

    2013-07-01

    Full Text Available The accumulation of ice, frost and snow on aircraft surfaces can drastically reduce the climb and maneuvering capabilities of an aircraft. The removal of such contamination prior to take off MUST be strictly adhered to in accordance with regulations and standards. The policy with respect to aircraft icing contamination should be “MAKE IT CLEAN AND KEEP IT CLEAN”. All personnel associated with the dispatch and/or operation of aircraft share the responsibility for ensuring that no aircraft is dispatched unless it is clear of ice, snow or frost.

  10. An evaluation of a hubless inducer and a full flow hydraulic turbine driven inducer boost pump

    Science.gov (United States)

    Lindley, B. K.; Martinson, A. R.

    1971-01-01

    The purpose of the study was to compare the performance of several configurations of hubless inducers with a hydrodynamically similar conventional inducer and to demonstrate the performance of a full flow hydraulic turbine driven inducer boost pump using these inducers. A boost pump of this type consists of an inducer connected to a hydraulic turbine with a high speed rotor located in between. All the flow passes through the inducer, rotor, and hydraulic turbine, then into the main pump. The rotor, which is attached to the main pump shaft, provides the input power to drive the hydraulic turbine which, in turn, drives the inducer. The inducer, rotating at a lower speed, develops the necessary head to prevent rotor cavitation. The rotor speed is consistent with present main engine liquid hydrogen pump designs and the overall boost pump head rise is sufficient to provide adequate main pump suction head. This system would have the potential for operating at lower liquid hydrogen tank pressures.

  11. Two-Mode Operation Engine Mount Design for Automotive Applications

    Directory of Open Access Journals (Sweden)

    Reza Tikani

    2012-01-01

    Full Text Available Hydraulic engine mounts are applied to the automotive applications to isolate the chassis from the high frequency noise and vibration generated by the engine as well as to limit the engine shake motions resulting at low frequencies. In this paper, a new hydraulic engine mount with a controllable inertia track profile is proposed and its dynamic behavior is investigated. The profile of the inertia track is varied by applying a controlled force to a cylindrical rubber disk, placed in the inertia track. This design provides a hydraulic engine mount design with an adjustable notch frequency location and also damping characteristics in shake motions. By using a simple control strategy, the efficiency of the proposed hydraulic engine mount in two-mode operation meaning isolating mode in the highway driving condition and damping mode in the shock motions, is investigated.

  12. ROBUST CONTROL OF AN ELECTRO-HYDRAULIC PROPORTIONAL SPEED CONTROL SYSTEM WITH A SINGLE-ROD HYDRAULIC ACTUATOR

    Institute of Scientific and Technical Information of China (English)

    Yang Jian; Xu Bing; Yang Huayong

    2005-01-01

    A robust control algorithm is proposed to focus on the non-linearity and parameters'uncertainties of an electro-hydraulic proportional speed control system (EHPSCS) with a single-rod hydraulic actuator. The robust controller proposed does not need to design stable compensator in advance, is simple in design and has large scope of uncertainty applications. The feedback gains of the robust controller proposed are small, so it is easily implemented in engineering applications.Experimental research on the speed control under the different conditions is carried out for an EHPSCS. Experimental results show that the robust controller proposed has better robustness subject to parametric uncertainties, and adaptability of parameters' variation of control system itself and plant parameter variation.

  13. Large and rapid melt-induced velocity changes in the ablation zone of the Greenland Ice Sheet.

    Science.gov (United States)

    van de Wal, R S W; Boot, W; van den Broeke, M R; Smeets, C J P P; Reijmer, C H; Donker, J J A; Oerlemans, J

    2008-07-04

    Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet. Within days, ice velocity reacts to increased meltwater production and increases by a factor of 4. Such a response is much stronger and much faster than previously reported. Over a longer period of 17 years, annual ice velocities have decreased slightly, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years. The positive-feedback mechanism between melt rate and ice velocity appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades.

  14. Hydraulic Redistribution: A Modeling Perspective

    Science.gov (United States)

    Daly, E.; Verma, P.; Loheide, S. P., III

    2014-12-01

    Roots play a key role in the soil water balance. They extract and transport water for transpiration, which usually represents the most important soil water loss in vegetated areas, and can redistribute soil water, thereby increasing transpiration rates and enhancing root nutrient uptake. We present here a two-dimensional model capable of describing two key aspects of root water uptake: root water compensation and hydraulic redistribution. Root water compensation is the ability of root systems to respond to the reduction of water uptake from areas of the soil with low soil water potential by increasing the water uptake from the roots in soil parts with higher water potential. Hydraulic redistribution is a passive transfer of water through the root system from areas of the soil with greater water potential to areas with lower water potential. Both mechanisms are driven by gradients of water potential in the soil and the roots. The inclusion of root water compensation and hydraulic redistribution in models can be achieved by describing root water uptake as a function of the difference in water potential between soil and root xylem. We use a model comprising the Richards equation for the water flow in variably saturated soils and the Darcy's equation for the water flow in the xylem. The two equations are coupled via a sink term, which is assumed to be proportional to the difference between soil and xylem water potentials. The model is applied in two case studies to describe vertical and horizontal hydraulic redistribution and the interaction between vegetation with different root depths. In the case of horizontal redistribution, the model is used to reproduce the fluxes of water across the root system of a tree subjected to uneven irrigation. This example can be extended to situations when only part of the root system has access to water, such as vegetation near creeks, trees at the edge of forests, and street trees in urban areas. The second case is inspired by recent

  15. Land Ice: Greenland & Antarctic ice mass anomaly

    Data.gov (United States)

    National Aeronautics and Space Administration — Data from NASA's Grace satellites show that the land ice sheets in both Antarctica and Greenland are losing mass. The continent of Antarctica (left chart) has been...

  16. On 100%Third-party testing for Hydraulic Engineering Quality of Guangdong%广东水利实行工程质量100%第三方检测模式探讨

    Institute of Scientific and Technical Information of China (English)

    陈小洁

    2016-01-01

    100%of project quality third-party testing as a new detection mode is embryonic development, and have been carried out in some areas in our country.Disadvantages of self testing by construction unit, and advantages of implementation of 100% third-party testing have been analyzed.According to the theory and practice, to implement 100%of the project quality third-party testing is the inevitable trend of engineering quality testing in Guangdong Province and even the hold country's water conservancy and even other construction industry.%水利工程实行工程质量100%第三方检测作为一种新的检测模式,在部分省份试点开展。该文分析了工程质量施工单位自检的弊端,对推行工程质量100%第三方检测具有的优势进行了探讨,对目前广东省所实施100%第三方检测的情况进行了简要介绍。根据理论分析和实践两个方面,在广东省乃至全国的水利工程全面实行工程质量100%第三方检测是工程质量检测的发展趋势。

  17. 生态水工学在引黄工程城区段的应用%Application of the Eco-Hydraulic Engineering Philosophy in Urban Section of Yellow River Diversion Project

    Institute of Scientific and Technical Information of China (English)

    崔宗昌; 翟付顺; 张秀省; 穆红梅

    2012-01-01

    Higher requirements were put forward in urban water conservancy projects construction in the Yellow River Diversion Project with the accelerated process of urbanization. Taking the ecological, landscape, engineering into account, six specific measures had been proposed based on sediment transport theory. They included the establishment of a benign natural water circulation system, using micro bending merits and white river plane, construction of the narrow width duplex water section of beach, creating a participatory hydrophilic interface, the design of flexible structural revetment and construction a rich and diverse biological community. All these measures will better achieve the harmonious coexistence of man and nature, and ensure the sustainable development of social economy.%随着城市化进程的加快,人们对引黄工程的城区水利工程建设提出了更高的要求.把生态水工学的理念与引黄工程特殊性相结合,参照水流挟沙理论提出了兼顾生态、景观、工程的的6点具体措施:建立良性自然的水循环系统、采用微弯曲直相间的河道平面、应用窄槽宽滩的复式水利断面、打造可参与性的亲水界面、设计柔性的结构性护岸以及营造丰富多样的生物群落.这些措施将更好地实现人与自然的和谐相处,保证社会经济的可持续发展.

  18. In-Situ Segregation of Ground Ice on Mars

    Science.gov (United States)

    Zent, A.; Sizemore, H. G.; Rempel, A. W.

    2011-12-01

    Several lines of evidence indicate the presence of nearly pure, segregated ground ice in the martian high latitudes. In particular, shallow ice containing only 1-2% soil was excavated by Phoenix. One hypothesis for the excess ice is that it developed in situ, via a mechanism analogous to terrestrial ice lenses. Problematically, terrestrial soil-ice segregation is driven by freeze/thaw cycles, which have not occurred recently on Mars. Here we investigate ice lens formation at T rates of vertical H2O transport typically limit lens growth to exchange with the atmosphere would be expected to outstrip and prevent in situ segregated ice lens formation in a salt-free soil. (Earlier in Mars' history however, we find that warmer temperatures frequently lead to macroscopic lens development.) The soils measured by Phoenix of course were not salt-free; in particular the presence of per-chlorate argues that our model must be expanded. The inclusion of even a single salt has multiple complicating effects. For saturated Mg(ClO4)2 solutions, the eutectic temperature is as low as 206 K. The resulting decrease in pore ice at low T leads to higher hydraulic permeability which would enhance growth rates. Liquid phase density increases, which increases the buoyancy forces on soil grains. Conversely, dynamic viscosity also increases, inhibiting lens growth. Both the heat capacity and thermal conductivity of the melt are also affected. At high concentrations, osmotic potentials begin to play a role in determining the movement of melt. Finally, all of these properties evolve continually with temperature, as the composition of the liquid phase changes. Understanding the ways in which these processes might affect in situ segregation of martian ground ice is a challenging and exciting undertaking.

  19. Arctic Sea Ice

    Science.gov (United States)

    Stroeve, J. C.; Fetterer, F.; Knowles, K.; Meier, W.; Serreze, M.; Arbetter, T.

    2004-12-01

    Of all the recent observed changes in the Arctic environment, the reduction of sea ice cover stands out most prominantly. Several independent analysis have established a trend in Arctic ice extent of -3% per decade from the late 1970s to the late 1990s, with a more pronounced trend in summer. The overall downward trend in ice cover is characterized by strong interannual variability, with a low September ice extent in one year typically followed by recovery the next September. Having two extreme minimum years, such as what was observed in 2002 and 2003 is unusual. 2004 marks the third year in a row of substantially below normal sea ice cover in the Arctic. Early summer 2004 appeared unusual in terms of ice extent, with May a record low for the satellite period (1979-present) and June also exhibiting below normal ice extent. August 2004 extent is below that of 2003 and large reductions in ice cover are observed once again off the coasts of Siberia and Alaska and the Greenland Sea. Neither the 2002 or 2003 anomaly appeared to be strongly linked to the positive phase of the Arctic Oscillation (AO) during the preceding winter. Similarly, the AO was negative during winter 2003/2004. In the previous AO framework of Rigor et al (2002), a positive winter AO implied preconditioning of the ice cover to extensive summer decay. In this hypothesis, the AO does not explain all aspects of the recent decline in Arctic ice cover, such as the extreme minima of 2002, 2003 and 2004. New analysis by Rigor and Wallace (2004) suggest that the very positive AO state from 1989-1995 can explain the recent sea ice minima in terms of changes in the Arctic surface wind field associated with the previous high AO state. However, it is also reasonable to expect that a general decrease in ice thickness accompanying warming would manifest itself as greater sensitivity of the ice pack to wind forcings and albedo feedbacks. The decrease in multiyear ice and attendant changes in ice thickness

  20. Percolation blockage: A process that enables melt pond formation on first year Arctic sea ice

    Science.gov (United States)

    Polashenski, Chris; Golden, Kenneth M.; Perovich, Donald K.; Skyllingstad, Eric; Arnsten, Alexandra; Stwertka, Carolyn; Wright, Nicholas

    2017-01-01

    Melt pond formation atop Arctic sea ice is a primary control of shortwave energy balance in the Arctic Ocean. During late spring and summer, the ponds determine sea ice albedo and how much solar radiation is transmitted into the upper ocean through the sea ice. The initial formation of ponds requires that melt water be retained above sea level on the ice surface. Both theory and observations, however, show that first year sea ice is so highly porous prior to the formation of melt ponds that multiday retention of water above hydraulic equilibrium should not be possible. Here we present results of percolation experiments that identify and directly demonstrate a mechanism allowing melt pond formation. The infiltration of fresh water into the pore structure of sea ice is responsible for blocking percolation pathways with ice, sealing the ice against water percolation, and allowing water to pool above sea level. We demonstrate that this mechanism is dependent on fresh water availability, known to be predominantly from snowmelt, and ice temperature at melt onset. We argue that the blockage process has the potential to exert significant control over interannual variability in ice albedo. Finally, we suggest that incorporating the mechanism into models would enhance their physical realism. Full treatment would be complex. We provide a simple temperature threshold-based scheme that may be used to incorporate percolation blockage behavior into existing model frameworks.

  1. Kagome spin ice

    Science.gov (United States)

    Mellado, Paula

    Spin ice in magnetic pyrochlore oxides is a peculiar magnetic state. Like ordinary water ice, these materials are in apparent violation with the third law of thermodynamics, which dictates that the entropy of a system in thermal equilibrium vanishes as its temperature approaches absolute zero. In ice, a "zero-point" entropy is retained down to low temperatures thanks to a high number of low-energy positions of hydrogen ions associated with the Bernal-Fowler ice-rules. Spins in pyrochlore oxides Ho2Ti 2O7 and Dy2Ti2O7 exhibit a similar degeneracy of ground states and thus also have a sizable zero-point entropy. A recent discovery of excitations carrying magnetic charges in pyrochlore spin ice adds another interesting dimension to these magnets. This thesis is devoted to a theoretical study of a two-dimensional version of spin ice whose spins reside on kagome, a lattice of corner-sharing triangles. It covers two aspects of this frustrated classical spin system: the dynamics of artificial spin ice in a network of magnetic nanowires and the thermodynamics of crystalline spin ice. Magnetization dynamics in artificial spin ice is mediated by the emission, propagation and absorption of domain walls in magnetic nanowires. The dynamics shows signs of self-organized behavior such as avalanches. The theoretical model compares favorably to recent experiments. The thermodynamics of the microscopic version of spin ice on kagome is examined through analytical calculations and numerical simulations. The results show that, in addition to the high-temperature paramagnetic phase and the low-temperature phase with magnetic order, spin ice on kagome may have an intermediate phase with fluctuating spins and ordered magnetic charges. This work is concluded with a calculation of the entropy of kagome spin ice at zero temperature when one of the sublattices is pinned by an applied magnetic field and the system breaks up into independent spin chains, a case of dimensional reduction.

  2. 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 ...

  3. Simulation and analysis of ice processes in an artificial open channel

    Institute of Scientific and Technical Information of China (English)

    GUO Xin-lei; YANG Kai-lin; FU Hui; WANG Tao; GUO Yong-xin

    2013-01-01

    The Middle Route Project for South-to-North Water Transfer,which consists of a long artificial open channel and various hydraulic constructions,is a big water conveyance system.A numerical modeling of water conveyance in the ice period for such large-scale and long distance water transfer project is developed based on the integration of a river ice model and an unsteady flow model with complex inner boundaries.A simplified method to obtain the same flow discharge in the upstream and downstream of the structure by neglecting the storage effect is proposed for dealing with the inner boundaries.According to the measured and design data in winter-spring period,the whole ice process,which includes the formation of the ice cover,its development,the melting and the breaking up as well as the ice-water dynamic response during the gate operation for the middle route,is simulated.The ice characteristics and the water conveyance capacity are both analyzed and thus the hydraulic control conditions for a safety regulation are obtained.At last,the uncertainties of some parameters related to the ice model are discussed.

  4. An ice lithography instrument

    Science.gov (United States)

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J. A.

    2011-06-01

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines.

  5. Fundamental and applied research in hydraulic transportation at the CSIR, Pretoria, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Sauermann, H.B.

    1983-03-01

    The paper outlines the type of work on hydraulic transportation of solids which has been and is being carried out by the National Mechanical Engineering Research Institute at Pretoria. Special emphasis is placed on handling mineral slurries, since the mining industry plays an important part in the South African economy. (7 refs.)

  6. Fundamental and applied research in hydraulic transportation at the CSIR, Pretoria, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Sauermann, H.B.

    1983-03-01

    This article outlines the type of work on hydraulic transportation of solids which has been and is being carried out by the National Mechanical Engineering Research Institute at Pretoria. Special emphasis is placed on handling mineral slurries, since the mining industry plays an important part in the South African economy.

  7. Leaf vein xylem conduit diameter influences susceptibility to embolism and hydraulic decline

    Science.gov (United States)

    Ecosystems worldwide are facing increasingly severe and prolonged droughts during which hydraulic failure from drought-induced embolism can lead to organ or whole plant death. Understanding the determinants of xylem failure across species is critical especially in leaves, the engine of plant growth....

  8. High resolution ice thickness, bed topography, and roughness of a land terminating section of the western Greenland Ice Sheet

    DEFF Research Database (Denmark)

    Lindback, K.; Pettersson, R.; Doyle, S. H.

    the spectral roughness. We see a strong correlation of low roughness values with the ice flow direction; this makes it important to assess the direction of the radar profiles in relation to the flow direction when calculating effective subglacial roughness for an area. Low roughness values and high surface......We present ice thickness and bed topography maps with high spatial resolution (250-500 m) of a large land terminating section of the western Greenland Ice Sheet. The maps cover the Isunnguata Sermia, Russell, and Leverett outlet glaciers and their catchment areas up to an elevation of ~1,700 m...... above sea level. The bed topography shows an intricate subglacial trough system, resembling the landscape in the proglacial area. We also calculate the hydraulic potential to get a proxy of the subglacial routing of water in the area. To analyse the geomorphological conditions of the bed, we calculated...

  9. Hydraulically Driven Grips For Hot Tensile Specimens

    Science.gov (United States)

    Bird, R. Keith; Johnson, George W.

    1994-01-01

    Pair of grips for tensile and compressive test specimens operate at temperatures up to 1,500 degrees F. Grips include wedges holding specimen inside furnace, where heated to uniform temperature. Hydraulic pistons drive wedges, causing them to exert clamping force. Hydraulic pistons and hydraulic fluid remain outside furnace, at room temperature. Cooling water flows through parts of grips to reduce heat transferred to external components. Advantages over older devices for gripping specimens in high-temperature tests; no need to drill holes in specimens, maintains constant gripping force on specimens, and heated to same temperature as that of specimen without risk of heating hydraulic fluid and acuator components.

  10. Dam breaking modeling on a river with ice cover : needs and tools : Hydro-Quebec perspective

    Energy Technology Data Exchange (ETDEWEB)

    Tchamen, G.W.; Quach, T.T.; Aubin, F.; Mellado, A. [Hydro-Quebec, Montreal, PQ (Canada). Unite Barrages and Hydraulique

    2007-07-01

    In order to ensure public safety, owners and operators of high capacity dams in Quebec have a legal obligation to conduct dam break analysis for each of their dams. Several scenarios of dam failure have been modelled under open water conditions to anticipate the worst-case scenario in terms of downstream consequences. However, the province of Quebec is located north of the 45th parallel, and most of the surface waters are ice covered in the winter. The presence of ice influences the river flow characteristics. As such, it is important to evaluate how ice may change the propagation of a surge wave and other important hydraulic parameters following a dam break. This paper reviewed traditional hydraulic methodologies and models used to perform dam break analyses with particular attention to the presence of ice. The changes in hydraulic processes in river flow involve various physical phenomena, some of which are poorly understood from a theoretical point of view. In the past several years, robust numerical techniques borrowed from fluid mechanics and aerodynamics have resulted in the development of robust hydrodynamic codes that effectively handle irregular bottom geometries, dry bed and mixed flow regimes in reasonable computational times. However, advances are still needed in the understanding of several ice processes, their formulation and their modeling. Data collection that would improve the understanding of the processes is also needed in order to reduce the level of uncertainties associated with the results of dam-break analysis. 22 refs., 3 tabs., 6 figs.

  11. Amery ice shelf DEM and its marine ice distribution

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Amery Ice Shelf is the largest ice shelf in East Antarctica. A new DEM was generated for this ice shelf, using kriging to interpolate the data from ICESat altimetry and the AIS-DEM. The ice thickness distribution map is converted from the new DEM, assuming hydrostatic equilibrium. The Amery Ice Shelf marine ice, up to 230 m thick, is concentrated in the northwest of the ice shelf. The volume of the marine ice is 2.38×103 km3 and accounts for about 5.6% of the shelf volume.

  12. Ice Tank Experiments Highlight Changes in Sea Ice Types

    Science.gov (United States)

    Wilkinson, Jeremy P.; DeCarolis, Giacomo; Ehlert, Iris; Notz, Dirk; Evers, Karl-Ulrich; Jochmann, Peter; Gerland, Sebastian; Nicolaus, Marcel; Hughes, Nick; Kern, Stefan; de la Rosa, Sara; Smedsrud, Lars; Sakai, Shigeki; Shen, Hayley; Wadhams, Peter

    2009-03-01

    With the current and likely continuing reduction of summer sea ice extent in the Arctic Ocean, the predominant mechanism of sea ice formation in the Arctic is likely to change in the future. Although substantial new ice formation occurred under preexisting ice in the past, the fraction of sea ice formation in open water likely will increase significantly. In open water, sea ice formation starts with the development of small ice crystals, called frazil ice, which are suspended in the water column [World Meteorological Organization, 1985]. Under quiescent conditions, these crystals accumulate at the surface to form an unbroken ice sheet known in its early stage as nilas. Under turbulent conditions, caused by wind and waves, frazil ice continues to grow and forms into a thick, soupy mixture called grease ice. Eventually the frazil ice will coalesce into small, rounded pieces known as pancake ice, which finally consolidate into an ice sheet with the return of calm conditions. This frazil/pancake/ice sheet cycle is currently frequently observed in the Antarctic [Lange et al., 1989]. The cycle normally occurs in regions that have a significant stretch of open water, because this allows for the formation of larger waves and hence increased turbulence. Given the increase of such open water in the Arctic Ocean caused by retreating summer sea ice, the frazil/pancake/ice sheet cycle may also become the dominant ice formation process during freezeup in the Arctic.

  13. Model Test Study on Ice Induced Vibration of A Compliant Conical Structure

    Institute of Scientific and Technical Information of China (English)

    HUNAG Yan; SHI Qing-zeng; SONG An

    2005-01-01

    The problem of ice induced vibration is common to ocean engineering of cold region countries. To study the ice induced vibration of a compliant conical structure, a series of model tests have been performed and some breakthrough progresses made. The ice sheet before the compliant conical structure is found to fail by two-time breaking in the tests. The process of two-time breaking behaves in two modes, and the general control of the ice and structural conditions determine the mode in which the ice force would behave. Two dynamic ice force functions are established respectively for the two modes of two-time breaking process in this paper. The numerical simulation results are in good agreement with the measured results, indicating that the dynamic ice force functions given in this paper can fully reflect the real situation of the dynamic ice force on a compliant conical structure.

  14. Ice-on-ice impact experiments.

    Science.gov (United States)

    Kato, Manabu; Iijima, Yu-Ichi; Arakawa, Masahiko; Okimura, Yasuyuki; Fujimura, Akio; Maeno, Norikazu; Mizutani, Hitoshi

    1995-02-01

    Impact experiments, cratering and fragmentation, on water ice were performed in order to test the scaling laws previously constructed on rocks and sands for studying the collision process in the planetary history. The installation of a vertical gas gun in a cold room at -18°C (255 K) made it possible to use a projectile of water ice and to get the detailed mass distribution of ice fragments. Experimental results indicated the necessity for large modification of those scaling laws. Material dependence was investigated by using projectiles of ice, aluminum, and polycarbonate. Differences were observed in the morphology and efficiencies of cratering and in the energies required to initiate the fragmentation. Moreover, an abrupt increase of cratering efficiency, suggesting a change of excavation mechanism, was found at a critical diameter of spalled crater. The mass (size) distribution of small ice fragments obeyed a power law with an exponent significantly larger than that in rocks. The exponent was the same as that in Saturn's ring particles estimated from the data by the microwave occultation, which indicates a collisional disruption ring origin.

  15. Small Airframe Manufacturer's Icing Perspective

    Science.gov (United States)

    Hoppins, Jim

    2009-01-01

    This viewgraph presentation describes the icing effects, risk mitigation practices, and icing certifications for various Cessna small aircraft models. NASA's role in the development of simulation tools for icing certifications is also discussed.

  16. Bacterial Ice Crystal Controlling Proteins

    Directory of Open Access Journals (Sweden)

    Janet S. H. Lorv

    2014-01-01

    Full Text Available Across the world, many ice active bacteria utilize ice crystal controlling proteins for aid in freezing tolerance at subzero temperatures. Ice crystal controlling proteins include both antifreeze and ice nucleation proteins. Antifreeze proteins minimize freezing damage by inhibiting growth of large ice crystals, while ice nucleation proteins induce formation of embryonic ice crystals. Although both protein classes have differing functions, these proteins use the same ice binding mechanisms. Rather than direct binding, it is probable that these protein classes create an ice surface prior to ice crystal surface adsorption. Function is differentiated by molecular size of the protein. This paper reviews the similar and different aspects of bacterial antifreeze and ice nucleation proteins, the role of these proteins in freezing tolerance, prevalence of these proteins in psychrophiles, and current mechanisms of protein-ice interactions.

  17. Co-Optimization of Fuels & Engines (Co-Optima) Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, John T [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-04

    This is the keynote presentation on the Co-Optimization of Fuels and Engines (Co-Optima) Initiative delivered at SAE International's ICE 2017 - 13th International Conference on Engines & Vehicles held in Capri, Italy.

  18. Inner gorges cut by subglacial meltwater during Fennoscandian ice sheet decay.

    Science.gov (United States)

    Jansen, J D; Codilean, A T; Stroeven, A P; Fabel, D; Hättestrand, C; Kleman, J; Harbor, J M; Heyman, J; Kubik, P W; Xu, S

    2014-05-09

    The century-long debate over the origins of inner gorges that were repeatedly covered by Quaternary glaciers hinges upon whether the gorges are fluvial forms eroded by subaerial rivers, or subglacial forms cut beneath ice. Here we apply cosmogenic nuclide exposure dating to seven inner gorges along ~500 km of the former Fennoscandian ice sheet margin in combination with a new deglaciation map. We show that the timing of exposure matches the advent of ice-free conditions, strongly suggesting that gorges were cut by channelized subglacial meltwater while simultaneously being shielded from cosmic rays by overlying ice. Given the exceptional hydraulic efficiency required for meltwater channels to erode bedrock and evacuate debris, we deduce that inner gorges are the product of ice sheets undergoing intense surface melting. The lack of postglacial river erosion in our seven gorges implicates subglacial meltwater as a key driver of valley deepening on the Baltic Shield over multiple glacial cycles.

  19. A Hydraulic Stress Measurement System for Deep Borehole Investigations

    Science.gov (United States)

    Ask, Maria; Ask, Daniel; Cornet, Francois; Nilsson, Tommy

    2017-04-01

    Luleå University of Technology (LTU) is developing and building a wire-line system for hydraulic rock stress measurements, with funding from the Swedish Research Council and Luleå University of Technology. In this project, LTU is collaborating with University of Strasbourg and Geosigma AB. The stress state influences drilling and drillability, as well as rock mass stability and permeability. Therefore, knowledge about the state of in-situ stress (stress magnitudes, and orientations) and its spatial variation with depth is essential for many underground rock engineering projects, for example for underground storage of hazardous material (e.g. nuclear waste, carbon dioxide), deep geothermal exploration, and underground infrastructure (e.g. tunneling, hydropower dams). The system is designed to conduct hydraulic stress testing in slim boreholes. There are three types of test methods: (1) hydraulic fracturing, (2) sleeve fracturing and (3) hydraulic testing of pre-existing fractures. These are robust methods for determining in situ stresses from boreholes. Integration of the three methods allows determination of the three-dimensional stress tensor and its spatial variation with depth in a scientific unambiguously way. The stress system is composed of a downhole and a surface unit. The downhole unit consists of hydraulic fracturing equipment (straddle packers and downhole imaging tool) and their associated data acquisition systems. The testing system is state of the art in several aspects including: (1) Large depth range (3 km), (2) Ability to test three borehole dimensions (N=76 mm, H=96 mm, and P=122 mm), (3) Resistivity imager maps the orientation of tested fracture; (4) Highly stiff and resistive to corrosion downhole testing equipment; and (5) Very detailed control on the injection flow rate and cumulative volume is obtained by a hydraulic injection pump with variable piston rate, and a highly sensitive flow-meter. At EGU General Assembly 2017, we would like to

  20. Helical coil thermal hydraulic model

    Science.gov (United States)

    Caramello, M.; Bertani, C.; De Salve, M.; Panella, B.

    2014-11-01

    A model has been developed in Matlab environment for the thermal hydraulic analysis of helical coil and shell steam generators. The model considers the internal flow inside one helix and its associated control volume of water on the external side, both characterized by their inlet thermodynamic conditions and the characteristic geometry data. The model evaluates the behaviour of the thermal-hydraulic parameters of the two fluids, such as temperature, pressure, heat transfer coefficients, flow quality, void fraction and heat flux. The evaluation of the heat transfer coefficients as well as the pressure drops has been performed by means of the most validated literature correlations. The model has been applied to one of the steam generators of the IRIS modular reactor and a comparison has been performed with the RELAP5/Mod.3.3 code applied to an inclined straight pipe that has the same length and the same elevation change between inlet and outlet of the real helix. The predictions of the developed model and RELAP5/Mod.3.3 code are in fairly good agreement before the dryout region, while the dryout front inside the helical pipes is predicted at a lower distance from inlet by the model.

  1. Development and test of a Microwave Ice Accretion Measurement Instrument (MIAMI)

    Science.gov (United States)

    Magenheim, B.; Rocks, J. K.

    1982-01-01

    The development of an ice accretion measurement instrument that is a highly sensitive, accurate, rugged and reliable microprocessor controlled device using low level microwave energy for non-instrusive real time measurement and recording of ice growth history, including ice thickness and accretion rate is discussed. Data is displayed and recorded digitally. New experimental data is presented, obtained with the instrument, which demonstrates its ability to measure ice growth on a two-dimensional airfoil. The device is suitable for aircraft icing protection. It may be mounted flush, non-intrusively, on any part of an aircraft skin including rotor blades and engine inlets.

  2. WATER ENERGY IN HYDROAMELIORATIVE SYSTEMS USING THE HYDRAULIC TRANSFORMER TYPE A. BARGLAZAN AND THE HYDRAULIC HAMMER (HYDRAULIC PUMP

    Directory of Open Access Journals (Sweden)

    Teodor Eugen Man

    2010-01-01

    Full Text Available This paper presents two examples of exploitation of water energy that can be used in the irrigation field. First of theseexamples is the hydraulic transformer type A. Barglazan used for irrigation, pumped water is taken directly from theriver’s well, using a hydraulic pump which simultaneously carried out a double transformation in this way: hydraulicenergy into mechanic energy and mechanical energy into hydraulic energy. Technology preparation and devices designwas done in record time, seeing that this constructive solution is more robust, reliable and with improved energyperformance versus the laboratory prototype. The experimental research which was made at 1:1 scale proved theirgood function over time. Another example is the hydraulic hammer (hydraulic pump that uses low-head energy topump water, with a global efficiency of about 10 - 50%. Currently, the new situation of private ownership of landprovides conditions for new pumping microstations to be made where irrigation is necessary and optimal hydrauliclocations exist.

  3. Layered clustering multi-fault diagnosis for hydraulic piston pump

    Science.gov (United States)

    Du, Jun; Wang, Shaoping; Zhang, Haiyan

    2013-04-01

    Efficient diagnosis is very important for improving reliability and performance of aircraft hydraulic piston pump, and it is one of the key technologies in prognostic and health management system. In practice, due to harsh working environment and heavy working loads, multiple faults of an aircraft hydraulic pump may occur simultaneously after long time operations. However, most existing diagnosis methods can only distinguish pump faults that occur individually. Therefore, new method needs to be developed to realize effective diagnosis of simultaneous multiple faults on aircraft hydraulic pump. In this paper, a new method based on the layered clustering algorithm is proposed to diagnose multiple faults of an aircraft hydraulic pump that occur simultaneously. The intensive failure mechanism analyses of the five main types of faults are carried out, and based on these analyses the optimal combination and layout of diagnostic sensors is attained. The three layered diagnosis reasoning engine is designed according to the faults' risk priority number and the characteristics of different fault feature extraction methods. The most serious failures are first distinguished with the individual signal processing. To the desultory faults, i.e., swash plate eccentricity and incremental clearance increases between piston and slipper, the clustering diagnosis algorithm based on the statistical average relative power difference (ARPD) is proposed. By effectively enhancing the fault features of these two faults, the ARPDs calculated from vibration signals are employed to complete the hypothesis testing. The ARPDs of the different faults follow different probability distributions. Compared with the classical fast Fourier transform-based spectrum diagnosis method, the experimental results demonstrate that the proposed algorithm can diagnose the multiple faults, which occur synchronously, with higher precision and reliability.

  4. Hydraulic Travel Time Tomography Appraisal Using Synthetic Data Sets

    Science.gov (United States)

    Brauchler, R.; Cheng, J.; Dietrich, P.; Everett, M.; Johnson, B.

    2003-12-01

    Hydraulic tomography is an aquifer characterization method allowing the two and three dimensional spatial identification of hydraulic properties in the subsurface. Such information is essential for rigorous analysis of a variety of engineering, geotechnical and hydrogeological problems within the context of water resources management. We propose a tomographic approach providing the inversion of travel times of multiwell slug tests. The inversion is based on the relation between the travel times of a recorded transient pressure curve and the diffusivity of the geological medium. Usually, just one value of a measured hydraulic signal, mostly the peak time, is used as the data for the inversion in order to reconstruct the diffusivity field of the investigated system. This situation is not satisfying because much information is lost. Therefore, we have developed a transformation factor allowing to apply our approach to several travel times characterizing each signal. Thereby, each travel time is inverted separately. The main focus is to appraise the influence of the various travel times on the inversion results. It can be assumed that early travel times are dominated by preferential flow along fast, high permeability paths, while the inversion results based on late travel times reflect an integration of the received signal over many flow paths. Synthetic data sets were created using the Finite Element Heat and Mass Transfer Code (FEHM) from Los Alamos National Laboratory. The data base of the inversion comprises simulated slug tests, in which the position of the sources (injection ports) and the receivers (observation ports) isolated with packers, are varied between the tests. We also investigate the effects of input parameters such as the number of source-receiver positions used, borehole storage and permeability distribution. The hydraulic tomography appraisal shows a strong dependence of the inversion results on the used travel times and input parameters. Results of

  5. Meth (Crank, Ice) Facts

    Science.gov (United States)

    ... That People Abuse » Meth (Crank, Ice) Facts Meth (Crank, Ice) Facts Listen Methamphetamine—meth for short—is a white, bitter powder. Sometimes ... clear or white shiny rock (called a crystal). Meth powder can be eaten or snorted up the ...

  6. Ice Core Investigations

    Science.gov (United States)

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  7. Making an Ice Core.

    Science.gov (United States)

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  8. Ice Core Investigations

    Science.gov (United States)

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  9. Sputtering of water ice

    DEFF Research Database (Denmark)

    Baragiola, R.A.; Vidal, R.A.; Svendsen, W.

    2003-01-01

    We present results of a range of experiments of sputtering of water ice together with a guide to the literature. We studied how sputtering depends on the projectile energy and fluence, ice growth temperature, irradiation temperature and external electric fields. We observed luminescence from...

  10. Testing The Ice

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The country’s fourth scientific expedition tothe North Pole starts OBSERVATION STATIONS:Members of China’s fourth Arctic expedition set up polar bear-proof "apple houses" on the ice surface of the Arctic Ocean on August 8 The Chinese ice breaker Xuelong

  11. Rheology of glacier ice

    Science.gov (United States)

    Jezek, K. C.; Alley, R. B.; Thomas, R. H.

    1985-01-01

    A new method for calculating the stress field in bounded ice shelves is used to compare strain rate and deviatoric stress on the Ross Ice Shelf, Antarctica. The analysis shows that strain rate (per second) increases as the third power of deviatoric stress (in newtons/sq meter), with a constant of proportionality equal to 2.3 x 10 to the -25th.

  12. HYDRAULIC CHARACTERISTICS OF VERTICAL VORTEX AT HYDRAULIC INTAKES

    Institute of Scientific and Technical Information of China (English)

    CHEN Yun-liang; WU Chao; YE Mao; JU Xiao-ming

    2007-01-01

    The trace of vertical vortex flow at hydraulic intakes is of the shape of spiral lines, which was observed in the presented experiments with the tracer technique. It represents the fluid particles flow spirally from the water surface to the underwater and rotate around the vortex-axis multi-cycle. This process is similar to the movement of screw. To describe the multi-circle spiral characteristics under the axisymmetric condition, the vertical vortex would change not only in the radial direction but also in the axial direction. The improved formulae for three velocity components for the vertical vortex flow were deduced by using the method of separation of variables in this article. In the improved formulae, the velocity components are the functions of the radial and axial coordinates, so the multi-circle spiral flow of vertical vortex could be simulated. The calculated and measured results for the vertical vortex flow were compared and the causes of errors were analyzed.

  13. Plans and Preliminary Results of Fundamental Studies of Ice Crystal Icing Physics in the NASA Propulsion Systems Laboratory

    Science.gov (United States)

    Struk, Peter; Tsao, Jen-Ching; Bartkus, Tadas

    2017-01-01

    This paper describes plans and preliminary results for using the NASA Propulsion Systems Lab (PSL) to experimentally study the fundamental physics of ice-crystal ice accretion. NASA is evaluating whether this facility, in addition to full-engine and motor-driven-rig tests, can be used for more fundamental ice-accretion studies that simulate the different mixed-phase icing conditions along the core flow passage of a turbo-fan engine compressor. The data from such fundamental accretion tests will be used to help develop and validate models of the accretion process. This paper presents data from some preliminary testing performed in May 2015 which examined how a mixed-phase cloud could be generated at PSL using evaporative cooling in a warmer-than-freezing environment.

  14. Ice Middleware in the New Solar Telescope's Telescope Control System

    Science.gov (United States)

    Shumko, S.

    2009-09-01

    The Big Bear Solar Observatory (BBSO) is now in the process of assembling and aligning its 1.6 m New Solar Telescope (NST). There are many challenges controlling NST and one of them is establishing reliable and robust communications between different parts of the Telescope Control System (TCS). For our TCS we selected Ice (Internet communication engine) from ZeroC, Inc. In this paper we discuss advantages of the Ice middleware, details of implementation and problems we face implementing it.

  15. Rock engineering: La Grande Complex, Quebec

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, D.K.; Levay, J.

    1982-08-01

    The paper presents an overview of rock engineering considerations in the Complex as related particularly to excavation and support problems. Examples are chosen to show the range of geological conditions encountered together with the engineering philosophy that has governed their treatment. Experience gained with unlined tunnels and channels for hydraulic purposes is discussed.

  16. Rotating ice blocks

    Science.gov (United States)

    Dorbolo, Stephane; Adami, Nicolas; Grasp Team

    2014-11-01

    The motion of ice discs released at the surface of a thermalized bath was investigated. As observed in some rare events in the Nature, the discs start spinning spontaneously. The motor of this motion is the cooling of the water close to the ice disc. As the density of water is maximum at 4°C, a downwards flow is generated from the surface of the ice block to the bottom. This flow generates the rotation of the disc. The speed of rotation depends on the mass of the ice disc and on the temperature of the bath. A model has been constructed to study the influence of the temperature of the bath. Finally, ice discs were put on a metallic plate. Again, a spontaneous rotation was observed. FNRS is thanked for financial support.

  17. Backfire prediction in a manifold injection hydrogen internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xing-hua; Liu, Fu-shui; Zhou, Lei; Sun, Bai-gang [School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081 (China); Schock, Harold J. [Engine Research Laboratory, Michigan State University, East Lansing, MI (United States)

    2008-07-15

    Hydrogen internal combustion engine (H2ICE) easily occur inlet manifold backfire and other abnormal combustion phenomena because of the low ignition energy, wide flammability range and rapid combustion speed of hydrogen. In this paper, the effect of injection timing on mixture formation in a manifold injection H2ICE was studied in various engine speed and equivalence ratio by CFD simulation. It was concluded that H2ICE of manifold injection have an limited injection end timing in order to prevent backfire in the inlet manifold. Finally, the limit of injection end timing of the H2ICE was proposed and validated by engine experiment. (author)

  18. Photolysis of aromatic pollutants in clean and dirty ice

    Science.gov (United States)

    Kahan, T.; Malley, P.; Stathis, A.

    2015-12-01

    Anthropogenic aromatic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and substituted benzenes often become more toxic following atmospheric oxidation. Photolysis of these pollutants in ice can be much faster than that in aqueous solution, which might lead to higher carcinogenic loadings in snow-covered regions. In this work we investigate two things. First, we investigate whether toluene, which has been detected at very elevated concentrations near hydraulic fracturing operations, can undergo photolysis at ice surfaces. Toluene in aqueous solution does not absorb sunlight, so photolysis has not been considered a potential atmospheric fate. However, benzene was recently demonstrated to undergo a significant red shift in its absorbance at ice surfaces, leading to photolysis under environmentally-relevant conditions. Here we show that toluene also undergoes photolysis at ice surfaces. In a second set of experiments, we have investigated the effects of organic matter on the photolysis kinetics ofPAHs in ice and at ice surfaces. We found that very small loadings of hydrophobic organics such as octanol can significantly suppress PAH photolysis kinetics in ice, but that the primary effect of the more soluble fulvic acid is competitive photon absorption. Our results show that photochemistry of anthropogenic pollutants can follow very different mechanisms and kinetics in ice than in aqueous solution, and that the photochemical fate of these pollutants depends strongly on the composition of the snow. These results have implications for pollutant fate and human health in a wide range of snow-covered environments including remote areas, cities, and regions near gas and oil extraction operations.

  19. 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....

  20. Hydraulic fracturing with distinct element method

    NARCIS (Netherlands)

    Pruiksma, J.P.; Bezuijen, A.

    2002-01-01

    In this report, hydraulic fracturing is investigated using the distinct element code PFC2D from Itasca. Special routines were written to be able to model hydraulic fracturing. These include adding fluid flow to PFC2D and updating the fluid flow domains when fractures appear. A brief description of t

  1. Hydraulic Actuator for Ganged Control Rods

    Science.gov (United States)

    Thompson, D. C.; Robey, R. M.

    1986-01-01

    Hydraulic actuator moves several nuclear-reactor control rods in unison. Electromagnetic pump pushes liquid lithium against ends of control rods, forcing them out of or into nuclear reactor. Color arrows show lithium flow for reactor startup and operation. Flow reversed for shutdown. Conceived for use aboard spacecraft, actuator principle applied to terrestrial hydraulic machinery involving motion of ganged rods.

  2. Control arrangement for the actuation of hydraulic consumers

    Energy Technology Data Exchange (ETDEWEB)

    Kussel, W.; Dettmers, M.; Weirich, W.

    1988-11-09

    An arrangement for controlling the actuation of hydraulic consumers, by selectively connecting the consumers to hydraulic pressure and return lines; the control arrangement comprising a respective hydraulically operated directional control valve associated with each of the hydraulic consumers, a respective electro-magnetically operated pre-control valve associated with each of the hydraulic directional control valves, and further electro-magnetically operated directional control valve means associated with the pre-control valves, each of the hydraulic consumers being connectible to the hydraulic pressure or return lines via the associated hydraulically operated directional control valve which is actuatable by a hydraulic control line leading from the output of the associated pre-control valve, wherein the inputs of the pre-control valves are connected directly to the hydraulic return line and indirectly, via the further control valve means, to the hydraulic return line or to a hydraulic control pressure line.

  3. Characteristics of Hydraulic Shock Waves in an Inclined Chute Contraction by Using Three Dimensional Numerical Model

    Science.gov (United States)

    Hsiao, Kai-Wen; Hsu, Yu-Chao; Jan, Chyan-Deng; Su, Yu-Wen

    2016-04-01

    The inclined rectangular chute construction is a common structure used in hydraulic engineering for typical reasons such as the increase of bottom slope, the transition from side channel intakes to tunnel spillways, the drainage construction, and the reduction of chute width due to bridges, flood diversion structures or irrigation systems. The converging vertical sidewalls of a chute contraction deflect the supercritical flow to form hydraulic shock waves. Hydraulic shock waves have narrow and locally extreme wavy surfaces, which commonly results in the requirement of higher height of sidewalls. Therefore, predicting the possible height and position of maximum hydraulic shock wave are necessary to design the required height of sidewalls to prevent flow overtopping. In this study, we used a three-dimensional computation fluid dynamics model (i.e., FLOW-3D) to simulate the characteristics of hydraulic shock waves in an inclined chute contraction. For this purpose, the parameters of simulated hydraulic shock wave, such as the shock angle, maximum shock wave height and maximum shock wave position in various conditions are compared with those calculated by the empirical relations obtained from literatures. We showed that the simulated results are extremely close to the experimental results. The numerical results validated the applicability of these empirical relations and extend their applicability to higher approach Froude numbers from 3.51 to 7.27. Furthermore, we also applied the Yuan-Shan-Tsu flood diversion channel under 200-year peak flow condition to FLOW-3D model to simulate the hydraulic shock waves and validate the effect of the installation of a diversion pier in the channel on promoting the stability of flow fluid. The results revealed that a diversion pier installed in the Yuan-Shan-Tsu flood diversion channel is helpful for improving the stability of flow field. In summary, this study demonstrates that FLOW-3D model can be used to simulate the

  4. Spatial stochastic and analytical approaches to describe the complex hydraulic variability inherent channel geometry

    Directory of Open Access Journals (Sweden)

    N. Hadadin

    2011-07-01

    Full Text Available The effects of basin hydrology on channel hydraulic variability for incised streams were investigated using available field data sets and models of watershed hydrology and channel hydraulics for Yazoo River Basin, USA. The study presents the hydraulic relations of bankfull discharge, channel width, mean depth, cross- sectional area, longitudinal slope, unit stream power, and runoff production as a function of drainage area using simple linear regression. The hydraulic geometry relations were developed for sixty one streams, twenty of them are classified as channel evaluation model (CEM Types IV and V and forty one of them are streams of CEM Types II and III. These relationships are invaluable to hydraulic and water resources engineers, hydrologists, and geomorphologists, involved in stream restoration and protection. These relations can be used to assist in field identification of bankfull stage and stream dimension in un-gauged watersheds as well as estimation of the comparative stability of a stream channel.

    Results of this research show good fit of hydraulic geometry relationships in the Yazoo River Basin. The relations indicate that bankfull discharge, channel width, mean depth, cross-sectional area have stronger correlation to changes in drainage area than the longitudinal slope, unit stream power, and runoff production for streams CEM Types II and III. The hydraulic geometry relations show that runoff production, bankfull discharge, cross-sectional area, and unit stream power are much more responsive to changes in drainage area than are channel width, mean depth, and slope for streams of CEM Types IV and V. Also, the relations show that bankfull discharge and cross-sectional area are more responsive to changes in drainage area than are other hydraulic variables for streams of CEM Types II and III. The greater the regression slope, the more responsive to changes in drainage area will be.

  5. GLERL Radiation Transfer Through Freshwater Ice

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radiation transmittance (ratio of transmitted to incident radiation) through clear ice, refrozen slush ice and brash ice, from ice surface to ice-water interface in...

  6. Mechanical design engineering handbook

    CERN Document Server

    Childs, Peter R N

    2013-01-01

    Mechanical Design Engineering Handbook is a straight-talking and forward-thinking reference covering the design, specification, selection, use and integration of machine elements fundamental to a wide range of engineering applications. Develop or refresh your mechanical design skills in the areas of bearings, shafts, gears, seals, belts and chains, clutches and brakes, springs, fasteners, pneumatics and hydraulics, amongst other core mechanical elements, and dip in for principles, data and calculations as needed to inform and evaluate your on-the-job decisions. Covering the full spectrum

  7. NASA Glenn Propulsion Systems Lab (PSL) Icing Facility Update

    Science.gov (United States)

    Thomas, Queito P.

    2015-01-01

    The NASA Glenn Research Center Propulsion Systems Lab (PSL) was recently upgraded to perform engine inlet ice crystal testing in an altitude environment. The system installed 10 spray bars in the inlet plenum for ice crystal generation using 222 spray nozzles. As an altitude test chamber, PSL is capable of simulation of in-flight icing events in a ground test facility. The system was designed to operate at altitudes from 4,000 ft. to 40,000 ft. at Mach numbers up to 0.8M and inlet total temperatures from -60F to +15F.

  8. Gravity-Driven Hydraulic Fractures

    Science.gov (United States)

    Germanovich, L. N.; Garagash, D.; Murdoch, L. C.; Robinowitz, M.

    2014-12-01

    This study is motived by a new method for disposing of nuclear waste by injecting it as a dense slurry into a hydraulic fracture that grows downward to great enough depth to permanently isolate the waste. Disposing of nuclear waste using gravity-driven hydraulic fractures is mechanically similar to the upward growth of dikes filled with low density magma. A fundamental question in both applications is how the injected fluid controls the propagation dynamics and fracture geometry (depth and breadth) in three dimensions. Analog experiments in gelatin [e.g., Heimpel and Olson, 1994; Taisne and Tait, 2009] show that fracture breadth (the short horizontal dimension) remains nearly stationary when the process in the fracture "head" (where breadth is controlled) is dominated by solid toughness, whereas viscous fluid dissipation is dominant in the fracture tail. We model propagation of the resulting gravity-driven (buoyant or sinking), finger-like fracture of stationary breadth with slowly varying opening along the crack length. The elastic response to fluid loading in a horizontal cross-section is local and can be treated similar to the classical Perkins-Kern-Nordgren (PKN) model of hydraulic fracturing. The propagation condition for a finger-like crack is based on balancing the global energy release rate due to a unit crack extension with the rock fracture toughness. It allows us to relate the net fluid pressure at the tip to the fracture breadth and rock toughness. Unlike the PKN fracture, where breadth is known a priori, the final breadth of a finger-like fracture is a result of processes in the fracture head. Because the head is much more open than the tail, viscous pressure drop in the head can be neglected leading to a 3D analog of Weertman's hydrostatic pulse. This requires relaxing the local elasticity assumption of the PKN model in the fracture head. As a result, we resolve the breadth, and then match the viscosity-dominated tail with the 3-D, toughness

  9. N-ICE2015: Multi-disciplinary study of the young sea ice system north of Svalbard from winter to summer.

    Science.gov (United States)

    Steen, Harald; Granskog, Mats; Assmy, Philipp; Duarte, Pedro; Hudson, Stephen; Gerland, Sebastian; Spreen, Gunnar; Smedsrud, Lars H.

    2016-04-01

    The Arctic Ocean is shifting to a new regime with a thinner and smaller sea-ice area cover. Until now, winter sea ice extent has changed less than during summer, as the heat loss to the atmosphere during autumn and winter is large enough form an ice cover in most regions. The insulating snow cover also heavily influences the winter ice growth. Consequently, the older, thicker multi-year sea ice has been replace by a younger and thinner sea. These large changes in the sea ice cover may have dramatic consequences for ecosystems, energy fluxes and ultimately atmospheric circulation and the Northern Hemisphere climate. To study the effects of the changing Arctic the Norwegian Polar Institute, together with national and international partners, launched from January 11 to June 24, 2015 the Norwegian Young Sea ICE cruise 2015 (N-ICE2015). N-ICE2015 was a multi-disciplinary cruise aimed at simultaneously studying the effect of the Arctic Ocean changes in the sea ice, the atmosphere, in radiation, in ecosystems. as well as water chemistry. R/V Lance was frozen into the drift ice north of Svalbard at about N83 E25 and drifted passively southwards with the ice until she was broken loose. When she was loose, R/V Lance was brought back north to a similar starting position. While fast in the ice, she served as a living and working platform for 100 scientist and engineers from 11 countries. One aim of N-ICE2015 is to present a comprehensive data-set on the first year ice dominated system available for the scientific community describing the state and changes of the Arctic sea ice system from freezing to melt. Analyzing the data is progressing and some first results will be presented.

  10. THE POTENTIAL IMPACT OF ICE-MINUS BACTERIA AS A FROST PROTECTANT IN NEW YORK TREE FRUIT PRODUCTION

    OpenAIRE

    John M. Love; Lesser, William H.

    1989-01-01

    Ice-nucleating bacteria, which are known to occur naturally on many crops and have been associated with frost damage, may be subject to control with genetically engineered bacteria, dubbed "ice-minus" bacteria. Ice-minus technology is designed to depress the critical temperature at which frost damage begins by displacing the natural population of ice-nucleating organisms. A trial product has been tested in the field with strawberries. Although tests with bacteriacidal compounds have suggested...

  11. Scaling hydraulic properties of a macroporous soil

    Science.gov (United States)

    Mohanty, Binayak P.

    1999-06-01

    Macroporous soils exhibit significant differences in their hydraulic properties for different pore domains. Multimodal hydraulic functions may be used to describe the characteristics of multiporosity media. I investigated the usefulness of scaling to describe the spatial variability of hydraulic conductivity (K(-h)) functions of a macroporous soil in Las Nutrias, New Mexico. Piecewise-continuous hydraulic conductivity functions suitable for macroporous soils in conjunction with a hybrid similar media-functional normalization scaling approach were used. Results showed that gravity-dominated flow and the related hydraulic conductivity (K(minus;h) functions of the macropore region are more readily scalable than capillary-dominated flow properties of the mesopore and micropore regions. A possible reason for this behavior is that gravity-dominated flow in the larger pores is mostly influenced by the pore diameter which remains more uniform as compared to tortuous mesopores and micropores with variable neck and body sizes along the pore length.

  12. Hydraulic conductivity of GCLs in MSW landfills

    Institute of Scientific and Technical Information of China (English)

    LI Guo-cheng; YANG Wu-chao; DAN Tang-hui

    2008-01-01

    The state of the art of the study on the hydraulic conductivity of GCLs is presented in terms of the in-fluence of the effective stress, chemical interactions, freeze - thaw cycles and temperature gradients. The chan-ges of void ratio caused by changes of effective stress have a direct linear effect on the hydraulic conductivity, regardless of the cation concentration or the thickness of the adsorbed layer. The hydraulic conductivity is relat-ed to the relative abundance of monovalent and divalent cation(RMD), and RMD has a great effect on the hy-draulic conductivity in weak solution. The long-term susceptibility of GCLs to increased hydraulic conductivity as a response to repeated freeze-thaw cycling is minimal, which has been proved after 150 freeze-thaw cycles. The potential of desiccation cracking increases with the increasing temperature gradient and is related to the ini-tial subsoil water content, the applied overburden stress, etc.

  13. Stacking disorder in ice I.

    Science.gov (United States)

    Malkin, Tamsin L; Murray, Benjamin J; Salzmann, Christoph G; Molinero, Valeria; Pickering, Steven J; Whale, Thomas F

    2015-01-07

    Traditionally, ice I was considered to exist in two well-defined crystalline forms at ambient pressure: stable hexagonal ice (ice Ih) and metastable cubic ice (ice Ic). However, it is becoming increasingly evident that what has been called cubic ice in the past does not have a structure consistent with the cubic crystal system. Instead, it is a stacking-disordered material containing cubic sequences interlaced with hexagonal sequences, which is termed stacking-disordered ice (ice Isd). In this article, we summarise previous work on ice with stacking disorder including ice that was called cubic ice in the past. We also present new experimental data which shows that ice which crystallises after heterogeneous nucleation in water droplets containing solid inclusions also contains stacking disorder even at freezing temperatures of around -15 °C. This supports the results from molecular simulations, that the structure of ice that crystallises initially from supercooled water is always stacking-disordered and that this metastable ice can transform to the stable hexagonal phase subject to the kinetics of recrystallization. We also show that stacking disorder in ice which forms from water droplets is quantitatively distinct from ice made via other routes. The emerging picture of ice I is that of a very complex material which frequently contains stacking disorder and this stacking disorder can vary in complexity depending on the route of formation and thermal history.

  14. Hydraulic test for evaluation of hydrophone VSP

    Energy Technology Data Exchange (ETDEWEB)

    Yabuuchi, Satoshi; Koide, Kaoru [Power Reactor and Nuclear Fuel Development Corp., Toki, Gifu (Japan). Tono Geoscience Center

    1997-12-01

    This hydraulic test was carried out at the test site of Tono Geoscience Center, Mizunami-shi, Gifu Pref. in order to evaluate the reliability of the hydraulic conductivity estimated from hydrophone VSP experiment. From March to April 1997, we carried out measurements of pore-water pressure at five depths and permeability tests at seven depths down to G.L.-300m, within a borehole drilled in granitic rock. We compared the results of hydraulic test with hydrophone VSP experiment on condition that a single open fracture existed, and we obtained two notable results. First, for the granitic rock at which a single open fracture was found by BTV and also detected by hydrophone VSP experiment, the hydraulic conductivity was 1.54 x 10{sup -7} cm/sec, while for the same granitic rock at which another single open fracture was found by BTV but not detected by hydrophone VSP experiment, the hydraulic conductivity was less than 6 x 10{sup -10} cm/sec. Second, we converted the hydraulic conductivity of 1.54 x 10{sup -7} cm/sec which was obtained in a hydraulic test section of length 2.5 m into an equivalent value for a single open fracture of width 1 mm. The converted value (3.8 x 10{sup -4} cm/sec) was similar to the hydraulic conductivity estimated from hydrophone VSP experiment. In conclusion, the hydraulic test result shows that hydrophone VSP is useful to estimate an approximate hydraulic conductivity of a single open fracture. (author)

  15. Thermal hydraulic characteristics during ingress of coolant and loss of vacuum events in fusion reactors

    Science.gov (United States)

    Takase, K.; Kunugi, T.; Seki, Y.; Akimoto, H.

    2000-03-01

    The thermal hydraulic characteristics in the vacuum vessel (VV) of a fusion reactor under an ingress of coolant event (ICE) and a loss of vacuum event (LOVA) were investigated quantitatively using preliminary experimental apparatuses. In the ICE experiments, pressure rise characteristics in the VV were clarified for experimental parameters of the wall temperature and water temperature and for cases with and without a blowdown tank. In addition, the functional performance of a blowdown tank with and without a water cooling system was examined and it was confirmed that the blowdown tank with a water cooling system is effective for suppressing the pressure rise during the ICE. In the LOVA experiments, the saturation time in the VV from vacuum to atmosphere was investigated for various breach sizes and it was found that the saturation time is in inverse proportion to the breach size. In addition, the characteristics of exchange flow through breaches were clarified for the different breach positions on the VV. It was proven from the experimental results that the exchange flow became a counter-current flow when the breach was positioned on the top of the VV and a stratified flow when it was formed on the side wall of the VV, and that the exchange flow under the stratified flow condition was smoother than that of counter-current flow. On the basis of these results, the severest breach condition in ITER was changed from the top-break case to the side-break case. To predict with high accuracy the thermal hydraulic characteristics during ICEs and LOVAs under ITER conditions, a large scale test facility will be necessary. The current conceptual design of the combined ICE-LOVA test facility with a scaling factor of 1/1000 in comparison with the ITER volume is presented.

  16. DLC coatings for hydraulic applications

    Institute of Scientific and Technical Information of China (English)

    Luca NOBILI; Luca MAGAGNIN

    2009-01-01

    Replacement of lubricating oils with water or low-viscosity fluids is highly desirable in many industrial fields, on account of the environmental and economical advantages. Low lubricity of water might be insufficient for proper operation of hydraulic components, and diamond-like carbon(DLC) coatings are very attractive as solid lubricant films. A remote-plasma PACVD process was utilized to deposit hydrogenated DLC coatings (a-C:H) on different substrates. Microindentation measurements show that the coating hardness is around 35 GPa. Tribological behavior was evaluated by block-on-ring tests performed in water and water with alumina. The wear rate was calculated after measuring the wear volume by a laser profilemeter. Morphological and compositional analysis of the wear tracks reveal that coating failure may occur by abrasive wear or delamination, depending on the substrate properties. Hard and smooth substrates give the best results and dispersed alumina particles increase the wear rate.

  17. Aircraft Hydraulic Systems Dynamic Analysis

    Science.gov (United States)

    1978-10-01

    4400 PSIG OUTLET PRESSURE ~’f UM5 S1 l .( FIF ~0RV lR 1 .I. AP (c R (V) IFWM) APPROX C ASE !VPý :iI S ReUN N•;MRF.. r p kN i t, isI A! f IN, I:E • ’l...and 1F.GI pump modelo were assumed from data supplied by CECO. 165 _ -- --- - SECTION V HYDRAULIC MOTOR MODEL DEVELOPMENT AND VERIFICATION A fixed...3 70 P.,0 601 ~4 M24.0 3 1p ’, 4 r I 1 1 ISIS 2411 APPENDIX E (CONT.) HSFR TECHNICAL MANUAL (AFAPL-TR-76-43, VOL. IV) 4.15 VANE PU`MP SUBROUTINE 4.15A

  18. Research on Trajectory Planning and Autodig of Hydraulic Excavator

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2017-01-01

    Full Text Available As the advances in computer control technology keep emerging, robotic hydraulic excavator becomes imperative. It can improve excavation accuracy and greatly reduce the operator’s labor intensity. The 12-ton backhoe bucket excavator has been utilized in this research work where this type of excavator is commonly used in engineering work. The kinematics model of operation device (boom, arm, bucket, and swing in excavator is established in both Denavit-Hartenberg coordinates for easy programming and geometric space for avoiding blind spot. The control approach is based on trajectory tracing method with displacements and velocities feedbacks. The trajectory planning and autodig program is written by Visual C++. By setting the bucket teeth’s trajectory, the program can automatically plan the velocity and acceleration of each hydraulic cylinder and motor. The results are displayed through a 3D entity simulation environment which can present real-time movements of excavator kinematics. Object-Oriented Graphics Rendering Engine and skeletal animation are used to give accurate parametric control and feedback. The simulation result shows that a stable linear autodig can be achieved. The errors between trajectory planning command and simulation model are analyzed.

  19. Analysis of load transfer stability control strategy in hydraulic synchronized continuous slippage

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-bo; WU Jian-zhong; ZHANG Xuan

    2006-01-01

    Hydraulic synchronized continuous slippage technique,which integrates mechanical,electrical and hydraulic control,is introduced in this paper for the practical requirements of some construction projects.The core of this technique (the stability of the load transfer) is illustrated in detail.Three speed control strategies to transfer the load-excessive,lower and same speed-are presented to accomplish the smoothness and stability in the process of slippage.An optimization of the speed control strategy (same speed) is deduced from the modeling analysis and its validity and maneuverability are tested by practical application,which provides evidence for similar engineering in theory and practice.

  20. Dynamic simulation and optimal control strategy for a parallel hybrid hydraulic excavator

    Institute of Scientific and Technical Information of China (English)

    Xiao LIN; Shuang-xia PAN; Dong-yun WANG

    2008-01-01

    The primary focus of this study is to investigate the control strategies of a hybrid system used in hydraulic excavators. First, the structure and evaluation target of hybrid hydraulic excavators are analyzed. Then the dynamic system model including batteries, motor and engine is built as the simulation environment to obtain control results. A so-called multi-work-point dynamic control strategy, which has both closed-loop speed PI (proportion integral) control and direct torque control, is proposed and studied in the simulation model. Simulation results indicate that the hybrid system with this strategy can meet the power demand and achieve better system stability and higher fuel efficiency.