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Sample records for hydraulic design considerations

  1. 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....

  2. 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.

  3. DOE handbook: Design considerations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-01

    The Design Considerations Handbook includes information and suggestions for the design of systems typical to nuclear facilities, information specific to various types of special facilities, and information useful to various design disciplines. The handbook is presented in two parts. Part 1, which addresses design considerations, includes two sections. The first addresses the design of systems typically used in nuclear facilities to control radiation or radioactive materials. Specifically, this part addresses the design of confinement systems and radiation protection and effluent monitoring systems. The second section of Part 1 addresses the design of special facilities (i.e., specific types of nonreactor nuclear facilities). The specific design considerations provided in this section were developed from review of DOE 6430.1A and are supplemented with specific suggestions and considerations from designers with experience designing and operating such facilities. Part 2 of the Design Considerations Handbook describes good practices and design principles that should be considered in specific design disciplines, such as mechanical systems and electrical systems. These good practices are based on specific experiences in the design of nuclear facilities by design engineers with related experience. This part of the Design Considerations Handbook contains five sections, each of which applies to a particular engineering discipline.

  4. 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

  5. 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.

  6. 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.

  7. Stream restoration hydraulic design course: lecture notes

    National Research Council Canada - National Science Library

    Newbury, R

    2002-01-01

    Steam restoration encompasses a broad range of activities and disciplines. This lecture series is designed for practitioners who must fit habitat improvement works in the hydraulics of degraded channels...

  8. Valve and Manifold considerations for Efficient Digital Hydraulic Machines

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Nørgård, Christian; Bech, Michael Møller;

    2016-01-01

    This paper seeks to shed light on the topic of design and sizing of switching valves and connecting manifolds found in large digital hydraulic motors, also known commercially as Digital Displacement Motors. These motors promise very high operation efficiencies with broad operation ranges, which set...... valves when considering also the manifold flow losses. A global optimization is conducted by use of the generalized differential evolution 3 algorithm, where the valve diameters, valve stroke lengths, actuator force capabilities and actuator timing signals are used as design variables. The results...

  9. System Topology Optimization - An Approach to System Design of Electro-Hydraulic-Mechanical Systems

    DEFF Research Database (Denmark)

    Andersen, T. O.; Hansen, M. R.; Conrad, Finn

    2003-01-01

    design the procedure attempts to find the optimal topology and the related parameters. The topology considerations comprise the type of hydraulic pump, the employment of knee linkages or not as well as the type of hydraulic actuators. The design variables also include the signals to the proportional......The current paper presents an approach to system design of combined electro-hydraulic-mechanical systems. The approach is based on the concurrent handling of the topology as well as the design parameters of the mechanical, hydraulic and controller sub- systems, respectively. Based on an initial...... valve in a number of predefined load cases as well as the hydraulic and mechanical parameters....

  10. Hydraulic design of geothermal probes; Hydraulische Auslegung von Erdwaermesondenanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Rosinski, Christoph; Zapp, Franz Josef [GEFGA mbH, Gesellschaft zur Entwicklung und Foerderung von Geothermen Anlagen, Limburg (Germany)

    2011-07-01

    Based on hydraulic considerations of geothermal probes of various designs and dimensions, the contribution under consideration reports on various influences on the heat transfer capacity of geothermal probes. The influence of laminar and turbulent pipe flow on the heat transfer capacity of geothermal probes is explained. Various parameters are considered such as the effect of various antifreezing compounds and the different types of construction of geothermal probes.

  11. DESIGN AND CONSTRUCTION OF A HYDRAULIC PISTON

    OpenAIRE

    Santos De La Cruz, Eulogio; Universidad Nacional Mayor de San Marcos; Rojas Lazo, Oswaldo; Universidad Nacional Mayor de San Marcos; Yenque Dedios, Julio; Universidad Nacional Mayor de San Marcos; Lavado Soto, Aurelio; Universidad Nacional Mayor de San Marcos

    2014-01-01

    A hydraulic system project includes the design, materials selection and construction of the hydraulic piston, hydraulic circuit and the joint with the pump and its accesories. This equiment will be driven by the force of moving fluid, whose application is in the devices of machines, tools, printing, perforation, packing and others. El proyecto de un sistema hidráulico, comprende el diseño, selección de materiales y construcción del pistón hidráulico, circuito hidráulico y el ensamble con l...

  12. Valve and Manifold considerations for Efficient Digital Hydraulic Machines

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Nørgård, Christian; Bech, Michael Møller

    2016-01-01

    This paper seeks to shed light on the topic of design and sizing of switching valves and connecting manifolds found in large digital hydraulic motors, also known commercially as Digital Displacement Motors. These motors promise very high operation efficiencies with broad operation ranges, which set...... strict requirements to the switching valves and the overall manifold design. To investigate this topic, the largest known digital motor (3.5 megawatt) is studied using models and optimization. Based on the limited information available about this motor, a detailed reconstruction of the motor architecture...... valves when considering also the manifold flow losses. A global optimization is conducted by use of the generalized differential evolution 3 algorithm, where the valve diameters, valve stroke lengths, actuator force capabilities and actuator timing signals are used as design variables. The results...

  13. 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.

  14. Digital hydraulic valving system. [design and development

    Science.gov (United States)

    1973-01-01

    The design and development are reported of a digital hydraulic valving system that would accept direct digital inputs. Topics include: summary of contractual accomplishments, design and function description, valve parameters and calculations, conclusions, and recommendations. The electrical control circuit operating procedure is outlined in an appendix.

  15. User interface design considerations

    DEFF Research Database (Denmark)

    Andersen, Simon Engedal; Jakobsen, Arne; Rasmussen, Bjarne D.

    1999-01-01

    When designing a user interface for a simulation model there are several important issues to consider: Who is the target user group, and which a priori information can be expected. What questions do the users want answers to and what questions are answered using a specific model?When developing...... the user interface of EESCoolTools these issues led to a series of simulation tools each with a specific purpose and a carefully selected set of input and output variables. To allow a more wide range of questions to be answered by the same model, the user can change between different sets of input...... and output variables. This feature requires special attention when designing the user interface and a special approach for controlling the user selection of input and output variables are developed. To obtain a consistent system description the different input variables are grouped corresponding...

  16. 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...

  17. Lock Culvert Valves; Hydraulic Design Considerations

    Science.gov (United States)

    2011-06-01

    the U.S. Army Engineer Waterways Experiment Station and U.S. Army Engineer Districts, St. Paul and Walla Walla . The prototype data suggest that the...been issued (U.S. Army Engineer District, Walla Walla 1955). 4.4.2 Lock No. 19 Lock 19 has a lift of 38.2 ft and flow is controlled with 14.5- by...Army Engineer Waterways Experiment Station. U.S. Army Engineer District, Walla Walla . 1955. Synchronization of lock filling valves, McNary Lock

  18. 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...

  19. Reactive barriers: hydraulic performance and design enhancements.

    Science.gov (United States)

    Painter, B D M

    2004-01-01

    The remediation of contaminated ground water is a multibillion-dollar global industry. Permeable reactive barriers (PRBs) are one of the leading technologies being developed in the search for alternatives to the pump-and-treat method. Improving the hydraulic performance of these PRBs is an important part of maximizing their potential to the industry. Optimization of the hydraulic performance of a PRB can be defined in terms of finding the balance between capture, residence time, and PRB longevity that produces a minimum-cost acceptable design. Three-dimensional particle tracking was used to estimate capture zone and residence time distributions. Volumetric flow analysis was used for estimation of flow distribution across a PRB and in the identification of flow regimes that may affect the permeability or reactivity of portions of the PRB over time. Capture zone measurements extended below the base of partially penetrating PRBs and were measured upgradient from the portion of aquifer influenced by PRB emplacement. Hydraulic performance analysis of standard PRB designs confirmed previously presented research that identified the potential for significant variation in residence time and capture zone. These variations can result in the need to oversize the PRB to ensure that downgradient contaminant concentrations do not exceed imposed standards. The most useful PRB design enhancements for controlling residence time and capture variation were found to be customized downgradient gate faces, velocity equalization walls, deeper emplacement of the funnel than the gate, and careful manipulation of the hydraulic conductivity ratio between the gate and the aquifer.

  20. Trends in Design of Water Hydraulics

    DEFF Research Database (Denmark)

    Conrad, Finn

    2005-01-01

    The paper presents and discusses a R&D-view on trends in development and best practise in design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus is on the advantages using...... ordinary tap water and the range of application areas are illustrated with examples, in particular within the food processing industry, humidification operations, water mist systems for fire fighting, high water pressure cleaners, water moisturising systems for wood processing, lumber drying process...... operate with pure water from the tap without additives of any kind. Hence water hydraulics takes the benefit of pure water as fluid being environmentally friendly, easy to clean sanitary design, non-toxic, non-flammable, inexpensive, readily available and easily disposable. The low-pressure tap water...

  1. Thermal Hydraulic Design of PWT Accelerating Structures

    CERN Document Server

    Yu, David; Chen Ping; Lundquist, Martin; Luo, Yan

    2005-01-01

    Microwave power losses on the surfaces of accelerating structures will transform to heat which will deform the structures if it is not removed in time. Thermal hydraulic design of the disk and cooling rods of a Plane Wave Transformer (PWT) structure is presented. Experiments to measure the hydraulic (pressure vs flow rate) and cooling (heat removed vs flow rate) properties of the PWT disk are performed, and results compared with simulations using Mathcad models and the COSMOSM code. Both experimental and simulation results showed that the heat deposited on the structure could be removed effectively using specially designed water-cooling circuits and the temperature of the structure could be controlled within the range required.

  2. Development of a hydraulic turbine design method

    Science.gov (United States)

    Kassanos, Ioannis; Anagnostopoulos, John; Papantonis, Dimitris

    2013-10-01

    In this paper a hydraulic turbine parametric design method is presented which is based on the combination of traditional methods and parametric surface modeling techniques. The blade of the turbine runner is described using Bezier surfaces for the definition of the meridional plane as well as the blade angle distribution, and a thickness distribution applied normal to the mean blade surface. In this way, it is possible to define parametrically the whole runner using a relatively small number of design parameters, compared to conventional methods. The above definition is then combined with a commercial CFD software and a stochastic optimization algorithm towards the development of an automated design optimization procedure. The process is demonstrated with the design of a Francis turbine runner.

  3. Design Considerations for Hydropower Development In a Water Distribution System

    Institute of Scientific and Technical Information of China (English)

    DavidP.Chamberlain; EdStewart; Fei-FanYeh; MichaelT.Stift

    2004-01-01

    Installation of a hydraulic turbine in a water distribution system involving long pipeline reaches requires several unique design considerations. For a fixed speed unit, the selection of design points for head and flow needs to be optimized to provide an operating envelope that would maximize the return on the investment given the widely varied flow and pressure conditions imposed by the water distribution system. The selection of a turbine design speed is essential in facilitating runner design, which must minimize the hydraulic pressure transients on turbine runaway that may result in overstressing the existing pipelines. Method and approach to evaluate these considerations are outlined. Relevant results for the selected design are presented using the 4.3 MW Rancho Penasquitos Pressure Control/Hydroelectric Facility as an illustrative example. Licensing requirements for small inline hydroelectric facilities are also briefly discussed.

  4. VIRTUAL DESIGN OF A NEW TYPE OF HYDRAULIC SUPPORT

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using virtual reality to design a new type of hydraulic support is discussed. That is how to make use of the virtual design to develop coal mining machine in practice. The advantages of virtual design are studied and the simple virtual reality system is built. The 3D parts and elements of hydraulic support are modeled with parametric design in CAD software, then exported to VR environment, in which the virtual hydraulic support is assembled, operated and tested. With the method, the errors and faults of design can be fined easily, many improvements are made and the new hydraulic support is developed successfully.

  5. 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.

  6. Analysis of Innovative Design of Energy Efficient Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    M Osman Abdalla

    2013-01-01

    Full Text Available Hydraulic cylinder actuators are used extensively in industrial, construction and agricultural works. The small sized outlet ports of the cylinders resist the flow of discharged oil; and as a result the piston motion is slowed down. This causes a lot of heat generation and energy loss within the actuators. The study investigates and analyzes the possibilities of reducing the hydraulic resistance and increasing efficiency of the hydraulic actuator. Conventional hydraulic cylinders are simulated in FLUENT. Results show that the small outlet ports are the sources of energy loss in hydraulic cylinders. A new hydraulic system was proposed as a solution to relieve the hydraulic resistance in the actuators. The proposed system is a four ports hydraulic cylinder fitted with a novel flow control valve. The proposed four ports cylinder was simulated and parameters such as ports sizes, loads and pressures are varied during the simulation. The hydraulic resisting forces, piston speed and mass flow rates are computed. Results show that the hydraulic resistance is significantly reduced in the proposed four ports actuators; and the proposed cylinders run faster than the conventional cylinders and a considerable amount of energyis saved as well.

  7. Design of a hydraulic actuator for active control of rotating machinery

    Science.gov (United States)

    Rashidi, Majid; Dirusso, Eliseo

    1991-01-01

    A hydraulic actuator is described which consists of a pump, a hydraulic servo-valve, and a thin elastic plate which transduces the generated pressure variations into forces acting on a mass which simulates the bearing of a rotor system. An actuator characteristic number is defined to provide a base for an optimum design of force actuators with combined weight, frequency, and force considerations. This characteristic number may also be used to compare hydraulic and electromagnetic force actuators. In tests, this actuator generated 182.3 Newton force at a frequency of 100 Hz and a displacement amplitude of 5.8 x 10 exp -5 meter.

  8. OPTIMAL HYDRAULIC DESIGN AND CAD APPLICATIONS OF AXIAL FLOW HYDRAULIC TURBINE'S RUNNER

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A method of the optimal hydraulic design and CAD application of runner blades of axial-flow hydraulic turbines are discussed on the basis of optimization principle and CAD technique in this paper. Based on the theory of fluid dynamics, the blade′s main geometrical parameter, working parameters and performances index of the blades and the relationship between them are analysed, and the mathematical model of optimal hydraulic design of axial-flow runners has been established. Through nonlinear programming, the problems can be solved. By making use of the calculation geometry and computer graphics, the distribution method of the singular points, and an CAD applied software, an optimal hydraulic design are presented.

  9. Parameter Designing for Heave Compensation Hydraulic System Installed in Deepwater

    Directory of Open Access Journals (Sweden)

    Zhao Teng

    2013-01-01

    Full Text Available The function diagram of active heave compensation hydraulic system has been given, besides, the mathematics model for the principal hydraulic components of the compensation system has been built, and the input-output relation between components has been made clear. Aimed at compensating work capacity for the system, design and research on parameters as the bearing pressure, the initial state and the maximum flow of hydraulic cylinder, accumulator and other principal components have been made separately, and standardized design has been accomplished in accordance with relevant standards. Furthermore, calculus and verification for the capacity of the hydraulic system in different working stages have been made in order to calculate the pressure lose of the system and provide objective data for the hardware system design of the hydraulic components of the heave compensation system.

  10. 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)…

  11. 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 ...

  12. 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...

  13. Power Management in Mobile Hydraulic Applications - An Approach for Designing Hydraulic Power Supply Systems

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen

    2004-01-01

    in a project to develop rules and methods for designing and controlling mobile hydraulic systems in the most energy efficient way, when also considering the operational aspects of the system. The paper first describes the thoughts and ideas behind the project and then focus on an automated approach to design......Throughout the last three decades energy consumption has become one of the primary design aspects in hydraulic systems, especially for mobile hydraulic systems, as power and cooling capacity here is at limited disposal. Considering the energy usage, this is dependent on component efficiency......, but even more important is the system topology. However, there are no rules or guidelines for what system topology to choose for a given application, in order to obtain the most energy efficient system, nor for how the energy should be distributed in the system. This paper describes the approach taken...

  14. Automated Hydraulic System Design and Power Management in Mobile Applications

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen

    a presentation of the used graph theory representation that is developed to represent a hydraulic open-circuit system and which is based on a numerical formulation that uniquely describe the system in terms of five set of design variables that describe respectively the topology, the components and the operating...... are found on most medium and high-end mobile hydraulic machinery. Despite the energy saving potentials that these systems posses, compared to the other open-circuit hydraulic system topologies, LS-system may still be subject to very low system efficiencies if not designed correctly. This is typically...... machines if operated in the intended and optimal work area, but due to an inappropriate system layout. Most of the power lost in open circuit hydraulic system systems is in this regard in the transmission part, i.e. hoses and fittings, and the valves used to control the system. A large part of the design...

  15. Future space suit design considerations.

    Science.gov (United States)

    1991-07-01

    Future space travel to the moon and Mars will present new challenges in space suit design. This paper examines the impact that working on the surface environment of the moon and Mars will have on the requirements of space suits. In particular, habitat pressures will impact suit weight and design. Potential structural materials are explored, as are the difficulties in designing a suit to withstand the severe dust conditions expected.

  16. Rook Jumping Maze Design Considerations

    Science.gov (United States)

    Neller, Todd W.; Fisher, Adrian; Choga, Munyaradzi T.; Lalvani, Samir M.; McCarty, Kyle D.

    We define the Rook Jumping Maze, provide historical perspective, and describe a generation method for such mazes. When applying stochastic local search algorithms to maze design, most creative effort concerns the definition of an objective function that rates maze quality. We define and discuss several maze features to consider in such a function definition. Finally, we share our preferred design choices, make design process observations, and note the applicability of these techniques to variations of the Rook Jumping Maze.

  17. Smile design--specific considerations.

    Science.gov (United States)

    Morley, J

    1997-09-01

    Smile design is a new discipline that has come to the forefront with the recent popularity of cosmetic dentistry techniques. This article explores some of the principles used in smile design that can enhance the esthetics of any anterior restorative procedure.

  18. Hydraulic design of a low-specific speed Francis runner for a hydraulic cooling tower

    Science.gov (United States)

    Ruan, H.; Luo, X. Q.; Liao, W. L.; Zhao, Y. P.

    2012-11-01

    The air blower in a cooling tower is normally driven by an electromotor, and the electric energy consumed by the electromotor is tremendous. The remaining energy at the outlet of the cooling cycle is considerable. This energy can be utilized to drive a hydraulic turbine and consequently to rotate the air blower. The purpose of this project is to recycle energy, lower energy consumption and reduce pollutant discharge. Firstly, a two-order polynomial is proposed to describe the blade setting angle distribution law along the meridional streamline in the streamline equation. The runner is designed by the point-to-point integration method with a specific blade setting angle distribution. Three different ultra-low-specificspeed Francis runners with different wrap angles are obtained in this method. Secondly, based on CFD numerical simulations, the effects of blade setting angle distribution on pressure coefficient distribution and relative efficiency have been analyzed. Finally, blade angles of inlet and outlet and control coefficients of blade setting angle distribution law are optimal variables, efficiency and minimum pressure are objective functions, adopting NSGA-II algorithm, a multi-objective optimization for ultra-low-specific speed Francis runner is carried out. The obtained results show that the optimal runner has higher efficiency and better cavitation performance.

  19. Mechanical considerations and design skills.

    Energy Technology Data Exchange (ETDEWEB)

    Alvis, Robert L.

    2008-03-01

    The purpose of the report is to provide experienced-based insights into design processes that will benefit designers beginning their employment at Sandia National Laboratories or those assuming new design responsibilities. The main purpose of this document is to provide engineers with the practical aspects of system design. The material discussed here may not be new to some readers, but some of it was to me. Transforming an idea to a design to solve a problem is a skill, and skills are similar to history lessons. We gain these skills from experience, and many of us have not been fortunate enough to grow in an environment that provided the skills that we now need. I was fortunate to grow up on a farm where we had to learn how to maintain and operate several different kinds of engines and machines. If you are like me, my formal experience is partially based upon the two universities from which I graduated, where few practical applications of the technologies were taught. What was taught was mainly theoretical, and few instructors had practical experience to offer the students. I understand this, as students have their hands full just to learn the theoretical. The practical part was mainly left up to 'on the job experience'. However, I believe it is better to learn the practical applications early and apply them quickly 'on the job'. System design engineers need to know several technical things, both in and out of their field of expertise. An engineer is not expected to know everything, but he should know when to ask an expert for assistance. This 'expert' can be in any field, whether it is in analyses, drafting, machining, material properties, testing, etc. The best expert is a person who has practical experience in the area of needed information, and consulting with that individual can be the best and quickest way for one to learn. If the information provided here can improve your design skills and save one design from having a problem

  20. Concept Design of Movable Beam of Hydraulic Press

    Directory of Open Access Journals (Sweden)

    Li Yancong

    2017-01-01

    Full Text Available The hydraulic press movable beam is one of the key components of the hydraulic press; its design quality impacts the accuracy of the workpiece that the press suppressed. In this paper, first, with maximum deflection and material strength as constraints, mechanical model of the movable beam is established; next, the concept design model of the moveable beam structure is established; the relationship among the force of the side cylinder, the thickness of the inclined plate, outer plate is established also. Taking movable beam of the 100MN type THP10-10000 isothermal forging hydraulic press as an example, the conceptual design result is given. This concept design method mentoned in the paper has general meaning and can apply to other similar product design.

  1. Lunar Navigation Architecture Design Considerations

    Science.gov (United States)

    D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael

    2009-01-01

    The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).

  2. Automated Hydraulic System Design and Power Management in Mobile Applications

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen

    machines if operated in the intended and optimal work area, but due to an inappropriate system layout. Most of the power lost in open circuit hydraulic system systems is in this regard in the transmission part, i.e. hoses and fittings, and the valves used to control the system. A large part of the design...... are working under the most optimal operating conditions. The above in this way constitute the background for the work that is the basis of this report, which deals with how to design and control open-circuit hydraulic systems with multiple consumers to obtain the largest energy utilization, when also...... a presentation of the used graph theory representation that is developed to represent a hydraulic open-circuit system and which is based on a numerical formulation that uniquely describe the system in terms of five set of design variables that describe respectively the topology, the components and the operating...

  3. CSM RCS Design Considerations and Failure Modes

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    Objectives include: a) Define major Command and Service Module (CSM) design considerations; b) List Command Module (CM) RCS failures and lessons learned; and c) List Service Module (SM) RCS failures and lessons learned.

  4. 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.

  5. HTGR fuel element structural design considerations

    Energy Technology Data Exchange (ETDEWEB)

    Alloway, R.; Gorholt, W.; Ho, F.; Vollman, R.; Yu, H.

    1986-09-01

    The structural design of the large HTGR prismatic core fuel elements involve the interaction of four engineering disciplines: nuclear physics, thermo-hydraulics, structural and material science. Fuel element stress analysis techniques and the development of structural criteria are discussed in the context of an overview of the entire design process. The core of the proposed 2240 MW(t) HTGR is described as an example where the design process was used. Probabalistic stress analysis techniques coupled with probabalistic risk analysis (PRA) to develop structural criteria to account for uncertainty are described. The PRA provides a means for ensuring that the proposed structural criteria are consistent with plant investment and safety risk goals. The evaluation of cracked fuel elements removed from the Fort St. Vrain reactor in the USA is discussed in the context of stress analysis uncertainty and structural criteria development.

  6. PRINCIPLE OF POST-PRODUCTION DESIGN OF HYDRAULIC ACTUATORS

    Directory of Open Access Journals (Sweden)

    A. V. Puzanov

    2015-01-01

    Full Text Available In work the problem of design-technology preparation of production of hydraulic actuators is staticized. The structure and business processes of design and production are analysed. Methods and means of reorganization of project works for the purpose of cutting-down of time of preparation of production are offered. The directions of reorganization of process of design are formulated. The principle of carrying out procedures of design-technology preparation of production of hydraulic actuators with use of ready elements of a production cycle is considered. The scheme of their practical realization at machine-building enterprise is offered. The assessment of growth of efficiency of design-technology preparation of production is given in machine-building enterprise.

  7. Effect of filter designs on hydraulic properties and well efficiency.

    Science.gov (United States)

    Kim, Byung-Woo

    2014-09-01

    To analyze the effect of filter pack arrangement on the hydraulic properties and the well efficiency of a well design, a step drawdown was conducted in a sand-filled tank model. Prior to the test, a single filter pack (SFP), granule only, and two dual filter packs (DFPs), type A (granule-pebble) and type B (pebble-granule), were designed to surround the well screen. The hydraulic properties and well efficiencies related to the filter packs were evaluated using the Hazen's, Eden-Hazel's, Jacob's, and Labadie-Helweg's methods. The results showed that the hydraulic properties and well efficiency of the DFPs were higher than those of a SFP, and the clogging effect and wellhead loss related to the aquifer material were the lowest owing to the grain size and the arrangement of the filter pack. The hydraulic conductivity of the DFPs types A and B was about 1.41 and 6.43 times that of a SFP, respectively. In addition, the well efficiency of the DFPs types A and B was about 1.38 and 1.60 times that of the SFP, respectively. In this study, hydraulic property and well efficiency changes were observed according to the variety of the filter pack used. The results differed from the predictions of previous studies on the grain-size ratio. Proper pack-aquifer ratios and filter pack arrangements are primary factors in the construction of efficient water wells, as is the grain ratio, intrinsic permeability (k), and hydraulic conductivity (K) between the grains of the filter packs and the grains of the aquifer. © 2014, National Ground Water Association.

  8. Design Optimization of Hydraulic Press Plate using Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    Akshay Vaishnav

    2016-05-01

    Full Text Available Metal forming is a process which is done by deforming metal work pieces to the desired shape and size using pressing or hammering action. Hydraulic presses are being used for forming and pressing operations with wide range of capacities. Hydraulic press machine works under continuous impact load. Because of this continuous load, tensile and compressive stresses are experienced in various parts of machine. These stresses cause permanent deformation in some parts of machine. This work is based on optimization of a 250-ton four pillar type hydraulic press considering constraints like design, weight and cost. The work is focused on design and optimization of top plate of the press machine. Top plate holds the hydraulic cylinder and is one of the most critical parts of the machine. The design is based on sizing optimization method and the results are validated by Finite Element method with proper boundary conditions. The CAD modelling has been carried out by PTC CREO and for FEA, ANSYS software is used.

  9. Human Factors Considerations in System Design

    Science.gov (United States)

    Mitchell, C. M. (Editor); Vanbalen, P. M. (Editor); Moe, K. L. (Editor)

    1983-01-01

    Human factors considerations in systems design was examined. Human factors in automated command and control, in the efficiency of the human computer interface and system effectiveness are outlined. The following topics are discussed: human factors aspects of control room design; design of interactive systems; human computer dialogue, interaction tasks and techniques; guidelines on ergonomic aspects of control rooms and highly automated environments; system engineering for control by humans; conceptual models of information processing; information display and interaction in real time environments.

  10. Implantable intraocular pressure monitoring systems: Design considerations

    KAUST Repository

    Arsalan, Muhammad

    2013-12-01

    Design considerations and limitations of implantable Intraocular Pressure Monitoring (IOPM) systems are presented in this paper. Detailed comparison with the state of the art is performed to highlight the benefits and challenges of the proposed design. The system-on-chip, presented here, is battery free and harvests energy from incoming RF signals. This low-cost design, in standard CMOS process, does not require any external components or bond wires to function. This paper provides useful insights to the designers of implantable wireless sensors in terms of design choices and associated tradeoffs. © 2013 IEEE.

  11. Design considerations for a gas microcontroller

    Science.gov (United States)

    Ritter, D. A.

    1986-01-01

    Some of the design problems that are now being addressed in consideration of a microcontroller for the upcoming GAS payload are discussed. Microcontrollers will be used to run the experiments and to collect and store the data from those experiments. Some of the requirements for a microcontroller are to be small, lightweight, have low power consumption, and high reliability. Some of the solutions that were developed to meet these design requirements are discussed. At present, the experiment is still in the design stage and the final design may change from what is presented here. The search for new integrated circuits which will do all that is needed all in one package continues.

  12. OPTIMUM DESIGN AND NON-LINEAR MODEL OF POWERPLANT HYDRAULIC MOUNT SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Shi Wenku; Min Haitao; Dang Zhaolong

    2003-01-01

    6-DOF non-linear mechanics model of powerplant hydraulic mount system is established. Optimum design of the powerplant hydraulic mount system is made with the hydraulic mount parameters as variables and with uncoupling of energy, rational disposition of nature frequency and minimum of reactive force at mount's location as objective functions. And based on the optimum design, software named ODPHMS (optimum design of powerplant hydraulic mount system) used in powerplant mount system optimum design is developed.

  13. Visual Metadiscourse: Designing the Considerate Text.

    Science.gov (United States)

    Kumpf, Eric P.

    2000-01-01

    Considers how visual metadiscourse provides design criteria for authors when considering the needs and expectations of readers. Notes the author's discussions of textual metadiscourse in technical writing classes since 1995. Notes an improvement in the cohesion and considerateness of student writing after rethinking their role as writers and the…

  14. 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.

  15. Effects of Microneedle Design Parameters on Hydraulic Resistance

    Science.gov (United States)

    Hood, R. Lyle; Kosoglu, Mehmet A.; Parker, Matthew; Rylander, Christopher G.

    2011-01-01

    Microneedles have been an expanding medical technology in recent years due to their ability to penetrate tissue and deliver therapy with minimal invasiveness and patient discomfort. Variations in design have allowed for enhanced fluid delivery, biopsy collection, and the measurement of electric potentials. Our novel microneedle design attempts to combine many of these functions into a single length of silica tubing capable of both light and fluid delivery terminating in a sharp tip of less than 100 microns in diameter. This manuscript focuses on the fluid flow aspects of the design, characterizing the contributions to hydraulic resistance from the geometric parameters of the microneedles. Experiments consisted of measuring the volumetric flow rate of de-ionized water at set pressures (ranging from 69-621 kPa) through a relevant range of tubing lengths, needle lengths, and needle tip diameters. Data analysis showed that the silica tubing (~150 micron bore diameter) adhered to within ±5% of the theoretical prediction by Poiseuille’s Law describing laminar internal pipe flow at Reynolds numbers less than 700. High hydraulic resistance within the microneedles correlated with decreasing tip diameter. The hydraulic resistance offered by the silica tubing preceding the microneedle taper was approximately 1-2 orders of magnitude less per unit length, but remained the dominating resistance in most experiments as the tubing length was >30 mm. These findings will be incorporated into future design permutations to produce a microneedle capable of both efficient fluid transfer and light delivery. PMID:22211159

  16. Design considerations for Mars photovoltaic power systems

    Science.gov (United States)

    Landis, Geoffrey A.; Appelbaum, Joseph

    1990-01-01

    Considerations for operation of a photovoltaic power system on Mars are discussed with reference to Viking Lander data. The average solar insolation at Mars is 590 W/sq m, which is reduced yet further by atmospheric dust. Of major concern are dust storms, which have been observed to occur on local as well as on global scales, and their effect on solar array output. While atmospheric opacity may rise to values ranging from 3 to 9, depending on storm severity, there is still an appreciable large diffuse illumination, even at high opacities, so that photovoltaic operation is still possible. If the power system is to continue to generate power even on high-optical-opacity (i.e., dusty atmosphere) days, it is important that the photovoltaic system be designed to collect diffuse irradiance as well as direct. Energy storage will be required for operation during the night. Temperature and wind provide additional considerations for array design.

  17. Design and Construction of a Hydraulic Ram Pump

    Directory of Open Access Journals (Sweden)

    Shuaibu Ndache MOHAMMED

    2007-09-01

    Full Text Available The Design and Fabrication of a Hydraulic Ram Pump (Hydram is undertaken. It is meant to lift water from a depth of 2m below the surface with no other external energy source required. Based on the design the volume flow rate in the derived pipe was 4.5238 × 10-5 m3/s (2.7 l/min, Power was 1.273 kW which results in an efficiency of 57.3%. The overall cost of fabrication of this hydram shows that the pump is relatively cheaper than the existing pumps.

  18. Design considerations for piezoelectric polymer ultrasound transducers.

    Science.gov (United States)

    Brown, L F

    2000-01-01

    Much work has been published on the design of ultrasound transducers using piezoelectric ceramics, but a great deal of this work does not apply when using the piezoelectric polymers because of their unique electrical and mechanical properties. The purpose of this paper is to review and present new insight into seven important considerations for the design of active piezoelectric polymer ultrasound transducers: piezoelectric polymer materials selection, transducer construction and packaging requirements, materials characterization and modeling, film thickness and active area design, electroding selection, backing material design, and front protection/matching layer design. Besides reviewing these design considerations, this paper also presents new insight into the design of active piezoelectric polymer ultrasonic transducers. The design and fabrication of an immersible ultrasonic transducer, which has no adhesive layer between the active element and backing layer, is included. The transducer features direct deposition of poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] copolymer onto an insulated aluminum backing substrate. Pulse-echo tests indicated a minimum insertion loss of 37 dB and -6 dB bandwidth of 9.8 to 22 MHz (71%). The use of polymer wear-protection/quarter-wave matching layers is also discussed. Test results on a P(VDF-TrFE) transducer showed that a Mylar/sup TM/ front layer provided a slight increase in pulse-echo amplitude of 15% (or 1.2 dB) and an increase in -6 dB pulse-echo fractional bandwidth from 86 to 95%. Theoretical derivations are reported for optimizing the active area of the piezoelectric polymer element for maximum power transfer at resonance. These derivations are extended to the special case for a low profile (i.e., thin) shielded transducer. A method for modeling the non-linear loading effects of a commercial pulser-receiver is also included.

  19. Novel method for the simultaneous quantification of soil hydraulic functions in the laboratory under consideration of shrinkage

    Science.gov (United States)

    Schindler, Uwe; Mueller, Lothar

    2013-04-01

    Knowledge about the soil hydraulic properties - water retention curve and unsaturated hydraulic conductivity - is required for soil water modelling and various soil hydrological studies. In general, soils and their pore size system are assumed to be rigid during the loss of water on drying. This is different from reality for many soils, especially for soils with high contents of clay or organic matter which are shrinking dependent on the pore pressure. As a result, the porosity, the pore size distribution and the bulk density of these soils are changing. Measurements of soil hydraulic functions with the classical methods are time consuming, the equipment is costly and the measuring results are affected by uncertainties. Methods enabling the quantification of soil hydraulic functions under consideration of shrinkage are missing. A method frequently used for the simultaneous determination of both the hydraulic functions of unsaturated soil samples is the evaporation method. Due to the limited range of common tensiometers, all methodological variations of the evaporation method in the past suffered from the limitation that the hydraulic functions could only be determined to a maximum tension of 50 kPa. The extended evaporation method (EEM) overcomes this restriction. Using new boyling delay tensiometers and applying the air-entry pressure of the tensiometer's porous ceramic cup as final tension value allows the quantification of the soil hydraulic functions in a range to close to the wilting point. Based on EEM a practicable method was developed which additionally allows the consideration of shrinkage. The experimental setup followed the system HYPROP which is a commercial device with vertically aligned tensiometers that is optimized to perform evaporation measurements. Preliminary investigations were conducted to study the geometrical change of 24 samples different in texture and origin. The samples were enwrapped with a rubber membrane impermeable for water and air

  20. Design and Development of Attachment for Hydraulic Stacker

    Directory of Open Access Journals (Sweden)

    S.H. Gawande

    2010-05-01

    Full Text Available The main purpose of this paper is to develop an Attachment which will enable the lateral movement of the manufacturing Dies by mounting it on the forks of any Hydraulic Stacker or Fork Lift. The Attachmentmanufactured is unique because it can be attached or mounted on any hydraulic stalker in the One Tonne range. The attachment is a combination of two separate bed of rollers, a lead screw, a gear mechanism and a moving frame which enables the hydraulic stacker to easily load or unload Dies upto the range of one tonne, in and out of Machine Presses and Storage Racks which reduces material handling time and cost, manual effort and increases safety. The developed attachment in this work can also be easily detached and kept aside when not in use, so that the stacker can be used for regular purposes in the logistics department. The detail design, fabrication and testing work is carried out at A.V.M Seating Systems Ltd, Pune-26.

  1. Design considerations for a ceramic fabric radiator

    Energy Technology Data Exchange (ETDEWEB)

    Pauley, K.A.; Webb, B.J. (Pacific Northwest Lab., Richland, WA (USA)); Klein, A.C. (Oregon State Univ., Corvallis, OR (USA). Dept. of Nuclear Engineering)

    1990-04-01

    The design of an Advanced Ceramic Fabric (ACF) thermal management device for use in both interplanetary and near-earth space must consider several important aspects of the environment. First, the radiation field at various locations is dominated by a proton component which deposits its energy on the surface of the device. Second, the ACF materials, as well as pressure liner materials, must also be compatible with the working fluids selected for the system. Third, the fluid dynamics and heat transfer characteristics of this device should be adequately characterized. With the proper consideration of materials and operating conditions, the Bubble Membrane Radiator (BMR) may be utilized for several advanced space missions. 17 refs.

  2. Design Rules for High Damping in Mobile Hydraulic Systems

    OpenAIRE

    Axin, Mikael; Krus, Petter

    2013-01-01

    This paper analyses the damping in pressure compensated closed centre mobile working hydraulic systems. Both rotational and linear loads are covered and the analysis applies to any type of pump controller. Only the outlet orifice in the directional valve will provide damping to a pressure compensated system. Design rules are proposed for how the system should be dimensioned in order to obtain a high damping. The volumes on each side of the load have a high impact on the damping. In case of a ...

  3. Hydraulic manipulator design, analysis, and control at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kress, R.L.; Jansen, J.F. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Love, L.J. [Oak Ridge Inst. for Science and Education, TN (United States); Basher, A.M.H. [South Carolina State Univ., Orangeburg, SC (United States)

    1996-09-01

    To meet the increased payload capacities demanded by present-day tasks, manipulator designers have turned to hydraulics as a means of actuation. Hydraulics have always been the actuator of choice when designing heavy-life construction and mining equipment such as bulldozers, backhoes, and tunneling devices. In order to successfully design, build, and deploy a new hydraulic manipulator (or subsystem) sophisticated modeling, analysis, and control experiments are usually needed. To support the development and deployment of new hydraulic manipulators Oak Ridge National Laboratory (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 hydraulics laboratory at ORNL has three different manipulators. First is a 6-Degree-of-Freedom (6-DoF), multi-planer, teleoperated, flexible controls test bed used for the development of waste tank clean-up manipulator controls, thermal studies, system characterization, and manipulator tracking. Finally, is a human amplifier test bed used for the development of an entire new class of teleoperated systems. To compliment the hardware in the hydraulics laboratory, ORNL has developed a hydraulics simulation capability including a custom package to model the hydraulic systems and manipulators for performance studies and control development. This paper outlines the history of hydraulic manipulator developments at ORNL, describes the hydraulics laboratory, discusses the use of the equipment within the laboratory, and presents some of the initial results from experiments and modeling associated with these hydraulic manipulators. Included are some of the results from the development of the human amplifier/de-amplifier concepts, the characterization of the thermal sensitivity of hydraulic systems, and end-point tracking accuracy studies. Experimental and analytical

  4. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic or pneumatic power and control-materials and... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component (such as pipe runs, fittings, flanges, and standard valves) for hydraulic or pneumatic power and...

  5. Practical design considerations for photovoltaic power station

    Science.gov (United States)

    Swanson, T. D.

    Aspects of photovoltaic (PV) technology are discussed along with generic PV design considerations, taking into account the resource sunlight, PV modules and their reliability, questions of PV system design, the support structure subsystem, and a power conditioning unit subsystem. A description is presented of two recent projects which demonstrate the translation of an idea into actual working PV systems. A privately financed project in Denton, Maryland, went on line in early December, 1982, and began providing power to the local utility grid. It represents the first intermediate size, grid-connected, privately financed power station in the U.S. Based on firm quotes, the actual cost of this system is about $13/W peak. The other project, called the PV Breeder, is an energy independent facility which utilizes solar power to make new solar cells. It is also the first large industrial structure completely powered by the sun.

  6. Design of PI Controllers for Hydraulic Control Systems

    Directory of Open Access Journals (Sweden)

    LJubiša Dubonjić

    2013-01-01

    Full Text Available The paper proposes a procedure for design of PI controllers for hydraulic systems with long transmission lines which are described by models of high order. Design is based on the combination of the IE criterion and engineering specifications (settling time and relative stability as well as on the application of D-decomposition. In comparison with some known results, the method is of graphical character, and it is very simple (solving nonlinear algebraic equations is eliminated. The paper presents the algorithm of software procedure for design of the controller. The method is compared with other methods at the level of simulation, and its superiority is shown. By applying the Nyquist criterion, it is shown that the method possesses robustness in relation to non modelled dynamics.

  7. Optimization design of an interior permanent-magnet synchronous machine for a hybrid hydraulic excavator

    Institute of Scientific and Technical Information of China (English)

    Qi-huai CHEN; Qing-feng WANG; Tao WANG

    2015-01-01

    A hybrid power transmission system (HPTS) is a promising way to save energy in a hydraulic excavator and the electric machine is one of the key components of the system. In this paper, a design process for permanent-magnet synchronous machines (PMSMs) in a hybrid hydraulic excavator (HHE) is presented based on the analysis of the working conditions and requirements of an HHE. A parameterized design approach, which combines the analytical model and the 2D finite element method (FEM), is applied to the electric machine to improve the design efficiency and accuracy. The analytical model is employed to optimize the electric machine efficiency and obtain the stator dimension and flux density distribution. The rotor is designed with the FEM to satisfy the flux requirements obtained in stator design. The rotor configuration of the PMSM employs an interior magnet structure, thus resulting in some inverse saliency, which allows for much higher values in magnetic flux density. To reduce the rotor leakage, a disconnected type silicon steel block structure is adopted. To improve the air gap flux density distribution, the trapezoid permanent magnet (PM) and centrifugal rotor structure are applied to PMSM. Demagnetization and armature reactions are also taken into consideration and calculated by the FEM. A prototype of the newly designed electric machine has been fabri-cated and tested on the experimental platform. The analytical design results are validated by measurements.

  8. Hydraulic considerations in sampling the unsaturated zone with inclined gravity lysimeters

    Science.gov (United States)

    Oaksford, E.T.

    1983-01-01

    Inclined gravity lysimeters as deep as 5.39 meters below land surface designed for sampling soil water in coarse sand under continuous ponding conditions, were shown to be capable of collecting 10 liters per hour at an infiltration rate of 0.5 meter per hour. This represents a capture efficiency of approximately 50%, a value observed in two similar but shallower lysimeters. When lysimeters are installed from a trench or observation manhole, soil-water samples can be taken under virtually undisturbed conditions, avoiding the soil disturbance and filtration associated with porous-cup vacuum lysimeters. Successful operation requires that the sampler be designed for the hydraulic characteristics of the soil from which the water sample is to be extracted. Criteria for lysimeter dimensions can be established on the basis of pressure heads experienced during sampling, can be induced to flow into the lysimeter by gradient manipulation. Observed head gradients outside the lysimeter ranged between 1.7 and 2.2 times those across the lysimeter, which would seem to explain the observed capture efficiency. (USGS)

  9. Analysis of Innovative Design of Energy Efficient Hydraulic Actuators

    OpenAIRE

    M Osman Abdalla

    2013-01-01

    Hydraulic cylinder actuators are used extensively in industrial, construction and agricultural works. The small sized outlet ports of the cylinders resist the flow of discharged oil; and as a result the piston motion is slowed down. This causes a lot of heat generation and energy loss within the actuators. The study investigates and analyzes the possibilities of reducing the hydraulic resistance and increasing efficiency of the hydraulic actuator. Conventional hydraulic cylinders are simulate...

  10. Thermal hydraulic analysis of the annular flow helium heater design

    Science.gov (United States)

    Chen, N. C.; Sanders, J. P.

    1982-05-01

    Core support performance test (CSPT) by use of an existing facility, components flow test loop (CFTL), as part of the high temperature gas cooled reactor (HTGR) application program were conducted. A major objective of the CSPT is to study accelerated corrosion of the core graphite support structure in helium at reactor conditions. Concentration of impurities will be adjusted so that a 6 month test represents the 30 year reactor life. Thermal hydraulic and structural integrity of the graphite specimen, will be studied at high pressure of 7.24 MPa (1050 psi) and high temperature of 1000 deg C in a test vessel. To achieve the required high temperature at the test section, a heater bundle has to be specially designed and properly manufactured. Performance characteristics of the heater which were determined from an analysis based on this design are presented.

  11. LBB considerations for a new plant design

    Energy Technology Data Exchange (ETDEWEB)

    Swamy, S.A.; Mandava, P.R.; Bhowmick, D.C.; Prager, D.E. [Westinghouse Electric Corp., Pittsburgh, PA (United States)

    1997-04-01

    The leak-before-break (LBB) methodology is accepted as a technically justifiable approach for eliminating postulation of Double-Ended Guillotine Breaks (DEGB) in high energy piping systems. This is the result of extensive research, development, and rigorous evaluations by the NRC and the commercial nuclear power industry since the early 1970s. The DEGB postulation is responsible for the many hundreds of pipe whip restraints and jet shields found in commercial nuclear plants. These restraints and jet shields not only cost many millions of dollars, but also cause plant congestion leading to reduced reliability in inservice inspection and increased man-rem exposure. While use of leak-before-break technology saved hundreds of millions of dollars in backfit costs to many operating Westinghouse plants, value-impacts resulting from the application of this technology for future plants are greater on a per plant basis. These benefits will be highlighted in this paper. The LBB technology has been applied extensively to high energy piping systems in operating plants. However, there are differences between the application of LBB technology to an operating plant and to a new plant design. In this paper an approach is proposed which is suitable for application of LBB to a new plant design such as the Westinghouse AP600. The approach is based on generating Bounding Analyses Curves (BAC) for the candidate piping systems. The general methodology and criteria used for developing the BACs are based on modified GDC-4 and Standard Review Plan (SRP) 3.6.3. The BAC allows advance evaluation of the piping system from the LBB standpoint thereby assuring LBB conformance for the piping system. The piping designer can use the results of the BACs to determine acceptability of design loads and make modifications (in terms of piping layout and support configurations) as necessary at the design stage to assure LBB for the, piping systems under consideration.

  12. Design consideration for magnetically suspended flywheel systems

    Science.gov (United States)

    Anand, D.; Kirk, J. A.; Frommer, D. A.

    1985-01-01

    Consideration is given to the design, fabrication, and testing of a magnetically suspended flywheel system for energy storage applications in space. The device is the prototype of a system combining passive suspension of the flywheel plate by samarium cobalt magnets and active control in the radial direction using eight separate magnetic coils. The bearing assembly was machined from a nickel-iron alloy, and the machine parts are all hydrogen annealed. Slots in the magnetic plate allow four independent quadrants for control. The motor/generator component of the system is a brushless dc-permanent magnetic/ironless engine using electronic communication. The system has been tested at over 2500 rpm with satisfactory results. The system characteristics of the flywheel for application in low earth orbit (LEO) are given in a table.

  13. Design considerations for miniaturized optical neural probes

    Science.gov (United States)

    Rudmann, Linda; Ordonez, Juan S.; Stieglitz, Thomas

    2016-03-01

    Neural probes are designed to selectively record from or stimulate nerve cells. In optogenetics it is desirable to build miniaturized and long-term stable optical neural probes, in which the light sources can be directly and chronically implanted into the animals to allow free movement and behavior. Because of the size and the beam shape of the available light sources, it is difficult to target single cells as well as spatially localized networks. We therefore investigated design considerations for packages, which encapsulate the light source hermetically and have integrated hemispherical lens structures that enable to focus the light onto the desired region, by optical simulations. Integration of a biconvex lens into the package lid (diameter = 300 μm, material: silicon carbide) increased the averaged absolute irradiance ηA by 298 % compared to a system without a lens and had a spot size of around 120 μm. Solely integrating a plano-convex lens (same diameter and material) results in an ηA of up to 227 %.

  14. Design Considerations For Night Vision Goggles

    Science.gov (United States)

    Glasheen, W. M.; Reiss, R. S.

    1985-01-01

    Baird Corporation of Bedford, Massachusetts, has designed and developed two similar night vision goggles. These goggles are binocular viewing to the wearer's eyes, but use a single objective lens and a single image intensifier tube. Binocular viewing is achieved by dividing a single image and sharing it between the'viewer's eyes. The goggles are self-sufficient, independent instruments which can be simply and easily interfaced with a face mask that the viewer wears. This paper covers the main design considerations that are associated with achieving the goals of these goggle configurations and their performance. Baird's first goggle design is designated the GP/NVG; the second is designated the AN/PVS-7. The GP/NVG night vision goggle is a high-performance, single intensifier tube, passive night vision device that provides the user with a 40-degree field of view at unity magnification. The fixed aperture, f/1.0 objective lens collects the available light and images it on the fiber optic faceplate of the second generation image intensifier tube. The image intensifier tube converts the real image at the fiber optic faceplate into electrons across the image, amplifies them, and then reconverts the electrons into a real, visible image at the fiber optic output of the tube. This image is then collimated to appear as if it is coming from infinity, split in two, and reimaged by the relay lenses. The eyelenses provide a magnified image to the user. The user can adjust each eyelens to clearly view the output faceplate of the image intensifier tube. This adjustment is made only once for each user. The objective focus can be manually set for distances from 25 centimeters to infinity. The general configuration of this night vision goggle is similar to that of a pair of single objective binocular field glasses. It is extremely lightweight (with most of the main construction molded from plastic) and compact for easy handling. All adjustments and on/off switching have been "human

  15. Hydraulic analysis and optimization design in Guri rehabilitation project

    Science.gov (United States)

    Cheng, H.; Zhou, L. J.; Gong, L.; Wang, Z. N.; Wen, Q.; Zhao, Y. Z.; Wang, Y. L.

    2016-11-01

    Recently Dongfang was awarded the contract for rehabilitation of 6 units in Guri power plant, the biggest hydro power project in Venezuela. The rehabilitation includes, but not limited to, the extension of output capacity by about 50% and enhancement of efficiency level. To achieve the targets the runner and the guide vanes will be replaced by the newly optimized designs. In addition, the out-of-date stay vanes with straight plate shape will be modified into proper profiles after considering the application feasibility in field. The runner and vane profiles were optimized by using state-of-the-art flow simulation techniques. And the hydraulic performances were confirmed by the following model tests. This paper describes the flow analysis during the optimization procedure and the comparison between various technical concepts.

  16. A Thermoelastic Hydraulic Fracture Design Tool for Geothermal Reservoir Development

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad Ghassemi

    2003-06-30

    Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Thus, knowledge of conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fracture are created in the reservoir using hydraulic fracturing. At times, the practice aims to create a number of parallel fractures connecting a pair of wells. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have set out to develop advanced thermo-mechanical models for design of artificial fractures and rock fracture research in geothermal reservoirs. These models consider the significant hydraulic and thermo-mechanical processes and their interaction with the in-situ stress state. Wellbore failure and fracture initiation is studied using a model that fully couples poro-mechanical and thermo-mechanical effects. The fracture propagation model is based on a complex variable and regular displacement discontinuity formulations. In the complex variable approach the displacement discontinuities are

  17. Tap Water Hydraulic Control Systems - Design and Industrial Applications. Chapter 7 in Advances in Hydraulic Control Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    Deals with development and design of modern tap water hydraulic components and systems, in particalar the Danfoss Nessie-family of components and systems working with pure tap water without any kind of additives. Typical industrial applications are presented and the perspectives of new industrial...

  18. Educational Design & ECOP: Considerations and propositions

    NARCIS (Netherlands)

    McKenney, Susan

    2016-01-01

    This presentation addresses foundational ideas about educational design, specifically: About design • What is educational design (research)? • What supports curriculum design? About designers • What are common designer struggles? • What can we learn from expert designers? • What are competencies of

  19. 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)

  20. Considerations for the design of Ada reusable packages

    Science.gov (United States)

    Nise, Norman S.; Giffin, Chuck

    1986-01-01

    Two important considerations that precede the design of Ada reusable packages (commonality and programming standards) are discuessed. First, the importance of designing packages to yield widespread commonality is expressed. A means of measuring the degree of applicability of packages both within and across applications areas is presented. Design consideration that will improve commonality are also discussed. Second, considerations for the development of programming standards are set forth. These considerations will lead to standards that will improve the reusability of Ada packages.

  1. Design of Transputer Controllers for Hydraulic Actuator Systems

    DEFF Research Database (Denmark)

    Conrad, Finn

    1996-01-01

    The paper deals with how transputers can be applied for fast controllers for hydraulic actuator systems. A general transputer-based control systems including a data acquisition transputer subsystem is presented. An application case: development of a mechatronic test facility with a fast hydraulic...

  2. Fluid-dynamic design optimization of hydraulic proportional directional valves

    Science.gov (United States)

    Amirante, Riccardo; Catalano, Luciano Andrea; Poloni, Carlo; Tamburrano, Paolo

    2014-10-01

    This article proposes an effective methodology for the fluid-dynamic design optimization of the sliding spool of a hydraulic proportional directional valve: the goal is the minimization of the flow force at a prescribed flow rate, so as to reduce the required opening force while keeping the operation features unchanged. A full three-dimensional model of the flow field within the valve is employed to accurately predict the flow force acting on the spool. A theoretical analysis, based on both the axial momentum equation and flow simulations, is conducted to define the design parameters, which need to be properly selected in order to reduce the flow force without significantly affecting the flow rate. A genetic algorithm, coupled with a computational fluid dynamics flow solver, is employed to minimize the flow force acting on the valve spool at the maximum opening. A comparison with a typical single-objective optimization algorithm is performed to evaluate performance and effectiveness of the employed genetic algorithm. The optimized spool develops a maximum flow force which is smaller than that produced by the commercially available valve, mainly due to some major modifications occurring in the discharge section. Reducing the flow force and thus the electromagnetic force exerted by the solenoid actuators allows the operational range of direct (single-stage) driven valves to be enlarged.

  3. Empirical Design Considerations for Industrial Centrifugal Compressors

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2012-01-01

    Full Text Available Computational Fluid Dynamics (CFD has been extensively used in centrifugal compressor design. CFD provides further optimisation opportunities for the compressor design rather than designing the centrifugal compressor. The experience-based design process still plays an important role for new compressor developments. The wide variety of design subjects represents a very complex design world for centrifugal compressor designers. Therefore, some basic information for centrifugal design is still very important. The impeller is the key part of the centrifugal stage. Designing a highly efficiency impeller with a wide operation range can ensure overall stage design success. This paper provides some empirical information for designing industrial centrifugal compressors with a focus on the impeller. A ported shroud compressor basic design guideline is also discussed for improving the compressor range.

  4. Hydraulically actuated hexapod robots design, implementation and control

    CERN Document Server

    Nonami, Kenzo; Irawan, Addie; Daud, Mohd Razali

    2014-01-01

    Legged robots are a promising locomotion system, capable of performing tasks that conventional vehicles cannot. Even more exciting is the fact that this is a rapidly developing field of study for researchers from a variety of disciplines. However, only a few books have been published on the subject of multi-legged robots. The main objective of this book is to describe some of the major control issues concerning walking robots that the authors have faced over the past 10 years. A second objective is to focus especially on very large hydraulically driven hexapod robot locomotion weighing more than 2,000 kg, making this the first specialized book on this topic. The 10 chapters of the book touch on diverse relevant topics such as design aspects, implementation issues, modeling for control, navigation and control, force and impedance control-based walking, fully autonomous walking, walking and working tasks of hexapod robots, and the future of walking robots. The construction machines of the future will very likel...

  5. Design of a Hydraulic Damper for Heavy Machinery

    Directory of Open Access Journals (Sweden)

    Emil Zaev

    2011-09-01

    Full Text Available A hydraulic unit consisting of an accumulator as energy storage element and an orifice providing friction was designed to damp oscillations of a machine during operation. In the first step, a model for the gas spring was developed from the ideal gas laws for the dimensioning the elements. To model the gas process with a graphical simulation tool it is necessary to find a form of the gas law which can be integrated with a numerical solver, such as Tustin, Runge-Kutta, or other. For simulating the working condition, the model was refined using the van der Waals equations for real gas. A unified model representation was found to be applied for any arbitrary state change. Verifications were made with the help of special state changes, adiabatic and isothermal. After determining the dimensional parameters, which are the accumulator capacity and the orifice size, the operational and the limiting parameters were to be found. The working process of a damper includes the gas pre-charging to a predefined pressure, the nearly isothermal static loading process, and the adiabatic change during the dynamic operation.

  6. Computational theory of cavitating flows for hydraulic turbomachinery with consideration of influence of water quality

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Previously it was assumed that the pressure within the cavity or on the cavity surface remained constant and the vapor pressure of clean water at 20°C and 0 m altitude was utilized as the computational boundary for cavitating flows in hydraulic turbomachinery. Cavitation was confused with vaporization, and the effect of water quality on cavitation pressure characteristics was not taken into account. In recent years, lots of experiments of cavitation pressure characteristics of different water qualities including different sand concentrations of sand water and different altitudes of clean water have been performed by the authors, and the important influences of water quality on cavitation pressure characteristic have been validated. Thus the water quality should be involved in the cavitating flows computation. In the present paper, the effect of water quality on the cavitation pressure characteristic is analyzed and the computational method and theory of cavitating flows for hydraulic turbomachinery that considers the influence of water quality are proposed. The theory is suitable for both the potential flow method and the two-phase flow method for cavitating flows simulation. Finally, the validation results for cavitating flows in a hydraulic tur- bine indicate the significant influences of water quality on the cavitating flow performance.

  7. Analysis of an controller design for an electro-hydraulic servo pressure regulator

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Andersen, Torben Ole; Madsen, A. M.;

    2009-01-01

    of the existing hydraulic components there are, however, still a need for being able to generate a hydraulic pilot pressure, as e.g. almost all open-circuit pumps are hydraulically controlled. The focus of the current paper is therefore on the analysis and controller design an electro-hydraulic servo pressure...... regulator, which generates a hydraulic LS-pressure based on an electrical reference, hereby synergistically integrating knowledge from all parts of the mechatronics area. The servo pressure regulator is used to generate the LS-signal for a variable displacement pump, and the paper rst presents...... to generate a controlled leakage  ow that aids in stabilising the system. The robustness of the system is then discussed in relation to dierent pilot line volumes and pump dynamics. Finally experimental results are presented, where the performance is compared to that of a similar hydraulic reference system...

  8. Networked Learning: Design Considerations for Online Instructors

    Science.gov (United States)

    Czerkawski, Betul C.

    2016-01-01

    The considerable increase in web-based knowledge networks in the past two decades is strongly influencing learning environments. Learning entails information retrieval, use, communication, and production, and is strongly enriched by socially mediated discussions, debates, and collaborative activities. It is becoming critical for educators to…

  9. Hydraulic design of a tilting weir allowing for periodic fish migration

    NARCIS (Netherlands)

    Hoitink, A.J.F.; Dommerholt, A.; Gerven, van L.P.A.

    2008-01-01

    The hydraulic design of a tilting weir is presented, which allows for periodic exchange of potadromous fish between freshwater ecosystems. The application domain includes inland waters that need to be isolated hydraulically, preserving the existing ecological connection with the surrounding areas as

  10. Optimal design of Stewart platforms based on expanding the control bandwidth while considering the hydraulic system design

    Institute of Scientific and Technical Information of China (English)

    Wei WANG; Hua-yong YANG; Jun ZOU; Xiao-dong RUAN; Xin FU

    2009-01-01

    We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart platform. The method is based on generalized natural frequency and takes hydraulic oil into consideration. A Lagrangian formulation which considers the whole leg inertia is presented to obtain the accurate equivalent mass matrix. Using the model, the effect of leg inertia and the influence of design parameters on the generalized natural frequency are investigated. Finally, numerical examples are presented to validate and confirm the efficiency of the mathematical model. The results show that the leg inertia, especially the piston part plays an important role in the dynamics. The optimum diameter ratio of the base to the moving platform is between 2 and 3, and the optimum joint angle ratio of the base to the moving platform is about 1. The smaller joint angles and a longer leg stroke are favorable for raising system frequencies. The system oil should be preprocessed for large platforms with a requirement for good dynamic performance.

  11. Design Formulae for Hydraulic Stability and Structural Integrity of Dolos Breakwater Round-Heads

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Jensen, Jacob Birk; Liu, Z.

    1995-01-01

    A rational design of Dolos armour unit should incorporate both the hydraulic stability and the structural integrity. The previous tests performed by Aalborg University (AU) resulted in design formulae for the trunk of a 1:1.5 slope Dolos breakwater without superstructure including both...... the hydraulic stability and the structural integrity. The objective of the round-head tests is to produce similar design formulae for Dolos armour in around-head. The tests will also include examinations of the hydraulic stability and run-up for a trunk section adjacent to the round-head. A run-up formula...

  12. BASIC FLOW PATTERNS AND OPTIMUM HYDRAULIC DESIGN OF A SUCTION BOX OF PUMPING STATION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A numerical method based on 3-D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types.In light of the computational results, the basic flow patterns in the boxes were revealed and a theoretical method to optimize hydraulically design of the suction box is developed.The box geometrical parameters, which influence the flow pattern in the box, could be optimized.The optimum criteria for the hydraulic design of the suction boxes of six types established, respectively.Furthermore, a summarization is given here based on the classification of the basic flow patterns in order to systematically understand the hydraulic design of suction boxes.

  13. Design and Analysis of High Pressure Hydraulic Filter for Marine Application

    Science.gov (United States)

    Momin, Toshin; Chandrasekar, RP; Balasubramanian, S.; Junaid Basha, AM, Dr.

    2017-05-01

    Filter is a critical component in ahydraulic system for maintaining the cleanliness of the fluid to required class level. InMarine applications very high reliable filter is required to operate continuously in saline environment. Design anddevelopment of high pressure hydraulic filter for Marine application is a challenging task. The design involves selection of special materialsandstringent qualification tests as per International standards. The present paper describes various stages of design and development of high pressure hydraulic filter for Marine application.

  14. Design and Optimization of Fast Switching Valves for Large Scale Digital Hydraulic Motors

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck

    of seat valves suitable for large scale digital hydraulic motors and detailed analysis methods for the pressure chambers of such machines. In addition, modeling methods of seat valves within this field have been developed, and a design method utilizing these models including optimization of subdomains has......The present thesis is on the design, analysis and optimization of fast switching valves for digital hydraulic motors with high power ratings. The need for such high power motors origins in the potential use of hydrostatic transmissions in wind turbine drive trains, as digital hydraulic machines...... have been shown to improve the overall efficiency and efficient operation range compared to traditional hydraulic machines. Digital hydraulic motors uses electronically controlled independent seat valves connected to the pressure chambers, which must be fast acting and exhibit low pressure losses...

  15. Mechatronic Design - Still a Considerable Challenge

    DEFF Research Database (Denmark)

    Torry-Smith, Jonas; Qamar, Ahsan; Achiche, Sofiane

    2011-01-01

    Development of mechatronic products is traditionally carried out by several design experts from different design domains. Performing development of mechatronic products is thus greatly challenging. In order to tackle this, the critical challenges in mechatronics have to be well understood and wel...

  16. Instructional design considerations promoting engineering design self-efficacy

    Science.gov (United States)

    Jackson, Andrew M.

    Engineering design activities are frequently included in technology and engineering classrooms. These activities provide an open-ended context for practicing critical thinking, problem solving, creativity, and innovation---collectively part of the 21st Century Skills which are increasingly needed for success in the workplace. Self-efficacy is a perceptual belief that impacts learning and behavior. It has been shown to directly impact each of these 21st Century Skills but its relation to engineering design is only recently being studied. The purpose of this study was to examine how instructional considerations made when implementing engineering design activities might affect student self-efficacy outcomes in a middle school engineering classroom. Student responses to two self-efficacy inventories related to design, the Engineering Design Self-Efficacy Instrument and Creative Thinking Self-Efficacy Inventory, were collected before and after participation in an engineering design curriculum. Students were also answered questions on specific factors of their experience during the curriculum which teachers may exhibit control over: teamwork and feedback. Results were analyzed using Pearson's correlation coefficients, paired and independent t-tests, and structural equation modeling to better understand patterns for self-efficacy beliefs in students. Results suggested that design self-efficacy and creative thinking self-efficacy are significantly correlated, r(1541) = .783, p showed that students perceive team inclusion and feedback as significant contributors to their self-efficacy beliefs, while team diversity was not related to self-efficacy. Separate models for each predictor demonstrated good fit. Recommendations are made based on the corresponding nature of engineering design self-efficacy and creative thinking self-efficacy: strategies encouraging self-efficacy in these domains may be transferrable. Instructors are made aware of the significant impact of classroom

  17. Design considerations for CELT adaptive optics

    Science.gov (United States)

    Dekany, Richard G.; Nelson, Jerry E.; Bauman, Brian J.

    2000-07-01

    California Institute of Technology and University of California have begun conceptual design studies for a new telescope for astronomical research at visible and infrared wavelengths. The California Extremely Large Telescope (CELT) is currently envisioned as a filled-aperture, steerable, segmented telescope of approximately 30 m diameter. The key to satisfying many of the science goals of this observatory is the availability of diffraction-limited wavefront control. We describe potential observing modes of CELT, including a discussion of the several major outstanding AO system architectural design issues to be resolved prior to the initiation of the detailed design of the adaptive optics capability.

  18. Mechatronic Design - Still a Considerable Challenge

    DEFF Research Database (Denmark)

    Torry-Smith, Jonas; Qamar, Ahsan; Achiche, Sofiane

    2011-01-01

    supported through applicable methods and tools. This paper aims at identifying the major challenges, by conducting a survey of the most relevant research work in mechatronic design. Solutions proposed in literature are assessed and illustrated through a case study in order to investigate, if the challenges...... can be handled appropriately by the methods, tools, and mindsets suggested by the mechatronic community. Using a real world mechatronics case, the paper identifies the areas where further research is required, by showing a clear connection between the actual problems faced during the design task......Development of mechatronic products is traditionally carried out by several design experts from different design domains. Performing development of mechatronic products is thus greatly challenging. In order to tackle this, the critical challenges in mechatronics have to be well understood and well...

  19. A Multilevel Consideration of Service Design Conditions

    DEFF Research Database (Denmark)

    Karpen, Ingo; Gemser, Gerda; Calabretta, Giulia

    2017-01-01

    Purpose The purpose of this paper is to advance the current understanding of organisational conditions that facilitate service design. Specifically, the focus is on organisational capabilities, interactive practices and individual abilities as units of analysis across service system levels. Groun...

  20. Design consideration of solar powered cars

    Energy Technology Data Exchange (ETDEWEB)

    Koten, Hasan; Yilmaz, Mustafa; Zafer Gul, M. [Marmara University Mechanical Engineering Department (Turkey)], E-mail: hasan.koten@marmara.edu.tr

    2011-07-01

    With the coming shortage of fossil fuels and the rising concerns over the environment, it is important to develop new technologies that reduce both energy consumption and pollution at the same time. Using solar energy is a good solution which could meet the world's energy needs. The aim of this study is to present the design process in the production of a solar powered car. Designing a solar powered car is a difficult task as there are strict requirements in term of efficiency: the car must have low drag resistance, be light-weight, and have low rolling resistance. In addition this paper presents the use of the solar powered Stirling engine technology rather than a photovoltaic conversion system for vehicle propulsion. This study presented a design process in the construction of a solar powered car and is expected to provide a new topic of research in the transportation field.

  1. Isotope Production Facility Conceptual Thermal-Hydraulic Design Review and Scoping Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Pasamehmetoglu, K.O.; Shelton, J.D.

    1998-08-01

    The thermal-hydraulic design of the target for the Isotope Production Facility (IPF) is reviewed. In support of the technical review, scoping calculations are performed. The results of the review and scoping calculations are presented in this report.

  2. Trajectory Design Considerations for Exploration Mission 1

    Science.gov (United States)

    Dawn, Timothy F.; Gutkowski, Jeffrey P.; Batcha, Amelia L.

    2017-01-01

    Exploration Mission 1 (EM-1) will be the first mission to send an uncrewed Orion vehicle to cislunar space in 2018, targeted to a Distant Retrograde Orbit (DRO). Analysis of EM-1 DRO mission opportunities in 2018 help characterize mission parameters that are of interest to other subsystems (e.g., power, thermal, communications, flight operations, etc). Subsystems request mission design trades which include: landing lighting, addition of an Orion main engine checkout burn, and use of auxiliary thruster only cases. This paper examines the evolving trade studies that incorporate subsystem feedback and demonstrate the feasibility of these constrained mission trajectory designs and contingencies.

  3. An Analysis of Ethical Considerations in Programme Design Practice

    Science.gov (United States)

    Govers, Elly

    2014-01-01

    Ethical considerations are inherent to programme design decision-making, but not normally explicit. Nonetheless, they influence whose interests are served in a programme and who benefits from it. This paper presents an analysis of ethical considerations made by programme design practitioners in the context of a polytechnic in Aotearoa/New Zealand.…

  4. The LACIE data bases: Design considerations

    Science.gov (United States)

    Westberry, L. E. (Principal Investigator)

    1979-01-01

    The implementation of direct access storage devices for LACIE is discussed with emphasis on the storage and retrieval of image data. Topics covered include the definition of the problem, the solution methodology (design decisions), the initial operational structure, and the modifications which were incorporated. Some conclusions and projections of future problems to be solved are also presented.

  5. Design Considerations for Phased Array Modules

    Science.gov (United States)

    1980-11-01

    basica )ly designed for C7 operation. In pulsed mode of oporation however, peak pov:e%.’ of 150:7 at 10.52GHz wras obtained for psoc pulse lengths and...repeating the above calculations with the appropriate value of referer:ce phase ýP applied to each element. Bearing in mind the tedious algebra involved in

  6. Section summary: Uncertainty and design considerations

    Science.gov (United States)

    Stephen Hagen

    2013-01-01

    Well planned sampling designs and robust approaches to estimating uncertainty are critical components of forest monitoring. The importance of uncertainty estimation increases as deforestation and degradation issues become more closely tied to financing incentives for reducing greenhouse gas emissions in the forest sector. Investors like to know risk and risk is tightly...

  7. Service-Learning Instructional Design Considerations

    Science.gov (United States)

    Maddrell, Jennifer

    2014-01-01

    This paper explores the design of "service-learning" experiences to engage college students in the real-world application of course subject matter. Service learning is an educational approach that combines community service, academic coursework, and work-based applied learning. Based on data gathered during a series of recent interviews…

  8. Service-Learning Instructional Design Considerations

    Science.gov (United States)

    Maddrell, Jennifer

    2014-01-01

    This paper explores the design of "service-learning" experiences to engage college students in the real-world application of course subject matter. Service learning is an educational approach that combines community service, academic coursework, and work-based applied learning. Based on data gathered during a series of recent interviews…

  9. Aeroelastic Considerations in the Preliminary Design Aircraft

    Science.gov (United States)

    1983-09-01

    DESIGN OBJECTIVES FEM FASO MODELINGWEGS TRNFRAIS SIZING RIGID AtP .FIRST FIRST FLEX FIRST FLEXSTATICLOADS [ IZING STATIC LOADS SIZING UPDATEFLEX SIZING...Structural Optimization by ASAT A computer software system called ASAT (Automatische Struktur Auslegung von Trag- flchen) exists at MBB which allows

  10. Considerations for efficient airflow design in cleanrooms

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Tengfang

    2004-07-29

    A high-performance cleanroom should provide efficient energy performance in addition to effective contamination control. Energy-efficient designs can yield capital and operational cost savings, and can be part of a strategy to improve productivity in the cleanroom industry. Based upon in-situ measurement data from ISO Class 5 clean rooms, this article discusses key factors affecting cleanroom air system performance and benefits of efficient airflow design in clean rooms. Cleanroom HVAC systems used in the semiconductor, pharmaceutical, and healthcare industries are very energy intensive, requiring large volumes of cleaned air to remove or dilute contaminants for satisfactory operations. There is a tendency, however, to design excessive airflow rates into cleanroom HVAC systems, due to factors such as design conservatism, lack of thorough understanding of airflow requirements, concerns about cleanliness reliability, and potential design and operational liabilities. Energy use of cleanroom environmental systems varies with system type and design, cleanroom functions, and the control of critical parameters such as temperature and humidity. In particular, cleanroom cleanliness requirements specified by cleanliness class have an impact on overall energy use. A previous study covering Europe and the US reveals annual cleanroom electricity usage for cooling and fan energy varies significantly depending on cleanliness class, and may account for up to three-quarters of total annual operating costs. A study on a semiconductor cleanroom in Japan found air delivery systems account for more than 30% of total power consumption. It is evident that the main factors dictating cleanroom operation energy include airflow rates and HVAC system efficiency. Improving energy efficiency in clean rooms may potentially contribute to significant savings in the initial costs of the facilities as well as operation and maintenance costs. For example, energy consumption by a typical chip

  11. An Optimisation Approach Applied to Design the Hydraulic Power Supply for a Forklift Truck

    DEFF Research Database (Denmark)

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

    2004-01-01

    -level optimisation approach, and is in the current paper exemplified through the design of the hydraulic power supply for a forklift truck. The paper first describes the prerequisites for the method and then explains the different steps in the approach to design the hydraulic system. Finally the results...... of the optimisation example for the forklift truck are presented along with a discussion of the method....

  12. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole;

    2011-01-01

    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable......Currently mobile hydraulics is in a transition phase, where electronic sensors and digital signal processors are becoming standard on a high number of machines, hereby replacing hydraulic pilot lines and offering new possibilities with regard to both control and feasibility. As most open...... displacement pump based on an electrical reference. The paper first presents the considered system and an experimentally verified model of this. A linearized model and a stability analysis is then presented, based on which an H∞control strategy is selected. A nominal performance and a robustly stable...

  13. Design considerations for tropical forest inventories

    Directory of Open Access Journals (Sweden)

    Ronald Edward McRoberts

    2013-06-01

    Full Text Available Forests contribute substantially to maintaining the global greenhouse gas balance, primarily because among the five economic sectors identified by the United Nations Framework Convention on Climate Change, only the forestry sector has the potential to remove greenhouse gas emissions from the atmosphere. In this context, development of national forest carbon accounting systems, particularly in countries with tropical forests, has emerged as an international priority. Because these systems are often developed as components of or in parallel with national forest inventories, a brief review of statistical issues related to the development of forest ground sampling designs is provided. This overview addresses not only the primary issues of plot configurations and sampling designs, but also to a lesser extent the emerging roles of remote sensing and uncertainty assessment. Basic inventory principles are illustrated for two case studies, the national forest inventory of Brazil with special emphasis on the state of Santa Catarina, and an inventory for Tanzania.

  14. Thermal expansion recovery microscopy: Practical design considerations

    Energy Technology Data Exchange (ETDEWEB)

    Mingolo, N., E-mail: nmingol@fi.uba.ar; Martínez, O. E. [Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colon 850, 1063 Buenos Aires (Argentina)

    2014-01-15

    A detailed study of relevant parameters for the design and operation of a photothermal microscope technique recently introduced is presented. The technique, named thermal expansion recovery microscopy (ThERM) relies in the measurement of the defocusing introduced by a surface that expands and recovers upon the heating from a modulated source. A new two lens design is presented that can be easily adapted to commercial infinite conjugate microscopes and the sensitivity to misalignment is analyzed. The way to determine the beam size by means of a focus scan and the use of that same scan to verify if a thermoreflectance signal is overlapping with the desired ThERM mechanism are discussed. Finally, a method to cancel the thermoreflectance signal by an adequate choice of a nanometric coating is presented.

  15. SOME CONSIDERATIONS ON FOREIGN LANGUAGE SYLLABUS DESIGN

    Directory of Open Access Journals (Sweden)

    Norica-Felicia BUCUR

    2014-05-01

    Full Text Available Studies and articles that focus on describing and classifying foreign language syllabuses are dominated by the product / process dichotomy. Nevertheless, this is not always the case, as there are authors who, apparently, use other criteria to produce their own taxonomy. Thus, this paper attempts to provide a brief chronological outline of the various descriptions found in the syllabus design literature, so that the principles underlying the proposed taxonomies could be identified and critical comparisons could be performed.

  16. Controller Design Considerations for ACM APFC Systems

    Directory of Open Access Journals (Sweden)

    Alexander Abramovitz

    2012-01-01

    Full Text Available This paper is concerned with performance of the current shaping network in Average Current Mode (ACM Active Power Factor Correction (APFC systems. Theoretical expressions for the ripple components are derived. Then, ripple interaction and impact on the current loop reference signal are investigated. A modification of the controller network is suggested that results in an improved Total Harmonic Distortion (THD. Design guidelines are suggested. The theoretical predictions were validated by simulation.

  17. Physics Considerations in the Design of NCSX

    Energy Technology Data Exchange (ETDEWEB)

    G.H. Neilson; M.C. Zarnstorff; L.P. Ku; E.A. Lazarus; P.K. Mioduszewski; M. Fenstermacher; E. Fredrickson; G.Y. Fu; A. Grossman; P.J. Heitzenroeder; R.H. Hatcher; S.P. Hirshman; S.R. Hudson; D.W. Johnson; H.W. Kugel; J.F. Lyon; R. Majeski; D.R. Mikkelsen; D.A. Monticello; B.E. Nelson; N. Pomphrey; W.T. Reiersen; A.H. Reiman; P.H. Rutherford; J.A. Schmidt; D.A. Spong; D.J. Strickler

    2002-10-09

    Compact stellarators have the potential to make steady-state, disruption-free magnetic fusion systems with beta approximately 5% and relatively low aspect ratio (R/ < 4.5) compared to most drift-optimized stellarators. Magnetic quasi-symmetry can be used to reduce orbit losses. The National Compact Stellarator Experiment (NCSX) is designed to test compact stellarator physics in a high-beta quasi-axisymmetric configuration and to determine the conditions for high-beta disruption-free operation. It is designed around a reference plasma with low ripple, good magnetic surfaces, and stability to the important ideal instabilities at beta approximately 4%. The device size, available heating power, and pulse lengths provide access to a high-beta target plasma state. The NCSX has magnetic flexibility to explore a wide range of equilibrium conditions and has operational flexibility to achieve a wide range of beta and collisionality values. The design provides space to accommodate plasma-facing components for divertor operation and ports for an extensive array of diagnostics.

  18. Wankel engines as steam expanders: design considerations

    Energy Technology Data Exchange (ETDEWEB)

    Badr, O.; Naik, S.; O' Callaghan, P.W.; Probert, S.D. (Cranfield Inst. of Tech., Bedford (GB). Dept. of Applied Energy)

    1991-01-01

    Rotary Wankel engines offer several advantages compared with turbines and other positive-displacement machines as the expansion devices in low-power-output Rankine-cycle systems. So a Wankel expander was selected as the most appropriate device for a steam Rankine-engine, operating principally as a mini combined heat-and-power unit, providing a mechanical output of 5-20 kW. A computer-aided-design technique for selecting the optimal geometry and location of the ports of the expander is described: the computer programs are available from the authors. Lubrication and possible material combinations are also discussed. (author).

  19. 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...

  20. Design Considerations in Capacitively Coupled Plasmas

    Science.gov (United States)

    Song, Sang-Heon; Ventzek, Peter; Ranjan, Alok

    2015-11-01

    Microelectronics industry has driven transistor feature size scaling from 10-6 m to 10-9 m during the past 50 years, which is often referred to as Moore's law. It cannot be overstated that today's information technology would not have been so successful without plasma material processing. One of the major plasma sources for the microelectronics fabrication is capacitively coupled plasmas (CCPs). The CCP reactor has been intensively studied and developed for the deposition and etching of different films on the silicon wafer. As the feature size gets to around 10 nm, the requirement for the process uniformity is less than 1-2 nm across the wafer (300 mm). In order to achieve the desired uniformity, the hardware design should be as precise as possible before the fine tuning of process condition is applied to make it even better. In doing this procedure, the computer simulation can save a significant amount of resources such as time and money which are critical in the semiconductor business. In this presentation, we compare plasma properties using a 2-dimensional plasma hydrodynamics model for different kinds of design factors that can affect the plasma uniformity. The parameters studied in this presentation include chamber accessing port, pumping port, focus ring around wafer substrate, and the geometry of electrodes of CCP.

  1. Consideration from a PBL perspective designing a virtual workshop

    DEFF Research Database (Denmark)

    Buus, Lillian; Bygholm, Ann

    2006-01-01

    This paper is taking departure in considerations of the pedagogical and learning oriented approaches made in the process from design to evaluation of the virtual workshop; as part of the MVU tutor course. Our focus in this paper is on elaborating and discussing the pedagogical considerations...... assignments. The design has tight and clear standards concentrated within only one week, as to give the participants opportunity to generate experiences in a considerable focus of collaboration, group work and different media supporting the assignments. In this paper we will elaborate the considerations...

  2. Design considerations for parallel graphics libraries

    Science.gov (United States)

    Crockett, Thomas W.

    1994-01-01

    Applications which run on parallel supercomputers are often characterized by massive datasets. Converting these vast collections of numbers to visual form has proven to be a powerful aid to comprehension. For a variety of reasons, it may be desirable to provide this visual feedback at runtime. One way to accomplish this is to exploit the available parallelism to perform graphics operations in place. In order to do this, we need appropriate parallel rendering algorithms and library interfaces. This paper provides a tutorial introduction to some of the issues which arise in designing parallel graphics libraries and their underlying rendering algorithms. The focus is on polygon rendering for distributed memory message-passing systems. We illustrate our discussion with examples from PGL, a parallel graphics library which has been developed on the Intel family of parallel systems.

  3. Digital libraries philosophies, technical design considerations, and example scenarios

    CERN Document Server

    Stern, David

    1999-01-01

    An unparalleled overview of current design considerations for your digital library! Digital Libraries: Philosophies, Technical Design Considerations, and Example Scenarios is a balanced overview of public services, collection development, administration, and systems support, for digital libraries, with advice on adopting the latest technologies that appear on the scene. As a professional in the library and information science field, you will benefit from this special issue that serves as an overview of selected directions, trends, possibilities, limitations, enhancements, design principals, an

  4. Design considerations for partial neutralization acid injection

    Energy Technology Data Exchange (ETDEWEB)

    Perl, T.R.; Van der Cook, R.E.

    1977-01-01

    It is currently estimated that, after vacuum evaporator-crystallizer of Hanford liquid wastes on the order of 10 million gallons of caustic residual liquor will remain. Partial Neutralization, the continuous addition of nitric acid to the slurry is being developed to allow additional volume reduction and reduce interim storage costs. Tests revealed that acid and liquor compositions as well as nozzle design are significant factors in the concentration of NO/sub x/ in the mild steel vessel vent system. The available literature information relating to mixing of up to 20 gallons per minute of acid with 14,000 gallons per minute of slurry is presented. Very rapid and thorough mixing of the injected acid is required, since reaction of even 0.1 percent of the injected acid with sodium nitrite in the slurry would yield unacceptable levels of NO/sub x/ in the vessel vent system. The mixing time calculated by a method developed herein was used to evaluate the proposed conceptual mixing nozzle.

  5. Design Considerations for Proposed Fermilab Integrable RCS

    Energy Technology Data Exchange (ETDEWEB)

    Eldred, Jeffrey [Fermilab; Valishev, Alexander

    2017-03-02

    Integrable optics is an innovation in particle accelerator design that provides strong nonlinear focusing while avoiding parametric resonances. One promising application of integrable optics is to overcome the traditional limits on accelerator intensity imposed by betatron tune-spread and collective instabilities. The efficacy of high-intensity integrable accelerators will be undergo comprehensive testing over the next several years at the Fermilab Integrable Optics Test Accelerator (IOTA) and the University of Maryland Electron Ring (UMER). We propose an integrable Rapid-Cycling Synchrotron (iRCS) as a replacement for the Fermilab Booster to achieve multi-MW beam power for the Fermilab high-energy neutrino program. We provide a overview of the machine parameters and discuss an approach to lattice optimization. Integrable optics requires arcs with integer-pi phase advance followed by drifts with matched beta functions. We provide an example integrable lattice with features of a modern RCS - long dispersion-free drifts, low momentum compaction, superperiodicity, chromaticity correction, separate-function magnets, and bounded beta functions.

  6. Design and Performance Analysis of a new Rotary Hydraulic Joint

    Science.gov (United States)

    Feng, Yong; Yang, Junhong; Shang, Jianzhong; Wang, Zhuo; Fang, Delei

    2017-07-01

    To improve the driving torque of the robots joint, a wobble plate hydraulic joint is proposed, and the structure and working principle are described. Then mathematical models of kinematics and dynamics was established. On the basis of this, dynamic simulation and characteristic analysis are carried out. Results show that the motion curve of the joint is continuous and the impact is small. Moreover the output torque of the joint characterized by simple structure and easy processing is large and can be rotated continuously.

  7. Analysis of and H∞ Controller Design For An Electro-Hydraulic Servo Pressure Regulator

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2011-01-01

    -circuit pumps are still hydraulically controlled, there is however still a need for being able to generate a hydraulic pilot pressure. The focus of the current paper is on the analysis and controller design of an electrohydraulic servo pressure regulator, which generates a hydraulic LS-pressure for a variable...... displacement pump based on an electrical reference. The paper first presents the considered system and an experimentally verified model of this. A linearized model and a stability analysis is then presented, based on which an H∞control strategy is selected. A nominal performance and a robustly stable...

  8. Planetary Protection Considerations in EVA System Design

    Science.gov (United States)

    Eppler, Dean B.; Kosmo, Joseph J.

    2011-01-01

    very little expression of these anomalies. hardware from the human-occupied area may limit (although not likely eliminate) external materials in the human habitat. Definition of design-to requirements is critical to understanding technical feasibility and costs. The definition of Planetary Protection needs in relation to EVA mission and system element development cost impacts should be considered and interpreted in terms of Plausible Protection criteria. Since EVA operations will have the most direct physical interaction with the Martian surface, PP needs should be considered in the terms of mitigating hardware and operations impacts and costs.

  9. An Optimisation Approach Applied to Design the Hydraulic Power Supply for a Forklift Truck

    DEFF Research Database (Denmark)

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

    2004-01-01

    This paper describes the first part of a method that may be used in the design of the most energy efficient hydraulic opencircuit systems, when also considering the operational aspects of the system given in the design specifications. The method builds on a numerically based multi-level optimisat......This paper describes the first part of a method that may be used in the design of the most energy efficient hydraulic opencircuit systems, when also considering the operational aspects of the system given in the design specifications. The method builds on a numerically based multi...

  10. Overview of pool hydraulic design of Indian prototype fast breeder reactor

    Indian Academy of Sciences (India)

    K Velusamy; P Chellapandi; S C Chetal; Baldev Raj

    2010-04-01

    Thermal hydraulics plays an important role in the design of liquid metal cooled fast breeder reactor components, where thermal loads are dominant. Detailed thermal hydraulic investigations of reactor components considering multi-physics heat transfer are essential for choosing optimum designs among the various possibilities. Pool hydraulics is multi-dimensional in nature and simple one-dimensional treatment for the same is often inadequate. Computational Fluid Dynamics (CFD) plays a critical role in the design of pool type reactors and becomes an increasingly popular tool, thanks to the advancements in computing technology. In this paper, thermal hydraulic characteristics of a fast breeder reactor, design limits and challenging thermal hydraulic investigations carried out towards successful design of Indian Prototype Fast Breeder Reactor (PFBR) that is under construction, are highlighted. Special attention is paid to phenomena like thermal stratification, thermal stripping, gas entrainment, inter-wrapper flow in decay heat removal and multiphysics cellular convection. The issues in these phenomena and the design solutions to address them satisfactorily are elaborated. Experiments performed for special phenomena, which are not amenable for CFD treatment and experiments carried out for validation of the computer codes have also been described.

  11. Modeling, Optimization, and Detailed Design of a Hydraulic Flywheel-Accumulator

    Science.gov (United States)

    Strohmaier, Kyle Glenn

    Improving mobile energy storage technology is an important means of addressing concerns over fossil fuel scarcity and energy independence. Traditional hydraulic accumulator energy storage, though favorable in power density, durability, cost, and environmental impact, suffers from relatively low energy density and a pressure-dependent state of charge. The hydraulic flywheel-accumulator concept utilizes both the hydro-pneumatic and rotating kinetic energy domains by employing a rotating pressure vessel. This thesis provides an in-depth analysis of the hydraulic flywheel-accumulator concept and an assessment of the advantages it offers over traditional static accumulator energy storage. After specifying a practical architecture for the hydraulic flywheel-accumulator, this thesis addresses the complex fluid phenomena and control implications associated with multi-domain energy storage. To facilitate rapid selection of the hydraulic flywheel-accumulator dimensions, computationally inexpensive material stress models are developed for each component. A drive cycle simulation strategy is also developed to assess the dynamic performance of the device. The stress models and performance simulation are combined to form a toolset that facilitates computationally-efficient model-based design. The aforementioned toolset has been embedded into a multi-objective optimization algorithm that aims to minimize the mass of the hydraulic flywheel-accumulator system and to minimize the losses it incurs over the course of a drive cycle. Two optimizations have been performed - one with constraints that reflect a vehicle-scale application, and one with constraints that reflect a laboratory application. At both scales, the optimization results suggest that the hydraulic flywheel-accumulator offers at least an order of magnitude improvement over traditional static accumulator energy storage, while operating at efficiencies between 75% and 93%. A particular hydraulic flywheel-accumulator design

  12. Hydraulic conclusions from chemical considerations: groundwater in sedimentary environments in the central part of the Pannonian Basin, Hungary

    Science.gov (United States)

    Varsányi, Irén; Kovács, Lajos Ó.; Bálint, András

    2015-05-01

    Hydro-chemical and isotopic data from different aquifers in the Great Hungarian Plain (the central part of the Pannonian Basin) were evaluated down to a depth of 2,740 m. The chemical and isotopic composition of water is influenced by its origin and by chemical and mixing processes. The analytical data and chemical considerations, together with geology, pressure conditions and evolution history of the area, explain the evolution of the subsurface water. Most of the samples are of meteoric origin, but there were some samples with a non-meteoric contribution, as indicated by the water stable isotopes, and these were identified as seawater trapped during the sedimentation in Lake Pannon. The sea contribution is traceable by the shifts in δ18O and δ2H and the chemical composition of the water, and is explained with an upward-driving force. Chemical considerations and spatial variability of the dissolved components suggest that distinct water bodies, each with a specific origin and chemical evolution, can be separately identified. Although in the Quaternary layers there are water bodies that can be considered to display complete flow systems (from recharge to discharge), in most water bodies present infiltration was not identified. The lack of recent recharge to several water bodies in various places and depths suggests a separation of the recharge and the discharge that occurred not in space, but in time. A possible explanation of the cessation of recharge is a significant change in the hydraulic circumstances, probably the surface elevation.

  13. Design and Experiment of Electronic-hydraulic Loading Test-bed Based on Tractor’s Hydraulic Steering By-wire

    Institute of Scientific and Technical Information of China (English)

    Yue JIN; Yang LU; Jiahui GONG; Zhixiong LU; Wenming LI; Jungan WU

    2015-01-01

    An Electro-hydraulic loading system is designed based on a test-bed of tractor’s hydraulic steering by-wire. To simulate the steering resistance driving tractor in many kinds of soils and roads,the loading force is controlled to make proportional and continuous variable by an electro-hydraulic proportional relief valve. A steering resistance loading test-bed is built to test three kinds of steering resistance including constant,step and sine style. Tire lateral resistance is also tested under different steering conditions. The result shows that the electro-hydraulic loading system has high stability and following performance. Besides,the system’s steady state error is lower than 3. 1%,and it meets the test requirement of tractor’s hydraulic steering by-wire.

  14. Multiobjective Optimization Design of Double-Row Blades Hydraulic Retarder with Surrogate Model

    Directory of Open Access Journals (Sweden)

    Liu Chunbao

    2015-02-01

    Full Text Available For the design of double-row blades hydraulic retarder involves too many parameters, the solution process of the optimal parameter combination is characterized by the large calculation load, the long calculation time, and the high cost. In this paper, we proposed a multiobjective optimization method to obtain the optimal balanced solution between the braking torque and volume of double-row blades hydraulic retarder. Moreover, we established the surrogate model for objective function with radial basis function (RBF, thus avoiding the time-consuming three-dimensional modeling and fluid simulation. Then, nondominated sorting genetic algorithm-II (NSGA-II was adopted to obtain the optimal combination solution of design variables. Moreover, the comparison results of computational fluid dynamics (CFD values of the optimal combination parameters and original design parameters indicated that the multiobjective optimization method based on surrogate model was applicable for the design of double-row blades hydraulic retarder.

  15. Design and performance characteristic analysis of servo valve-type water hydraulic poppet valve

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Hwan [Pusan National University, Busan (Korea, Republic of)

    2009-09-15

    For water hydraulic system control, the flow or pressure control using high-speed solenoid valve controlled by PWM control method could be a good solution for prevention of internal leakage. However, since the PWM control of on-off valves cause extensive flow and pressure fluctuation, it is difficult to control the water hydraulic actuators precisely. In this study, the servo valve-type water hydraulic valve using proportional poppet as the main valve is designed and the performance characteristics of the servo valve-type water hydraulic valve are analyzed. Furthermore, it is demonstrated through experiments that a decline in control chamber pressure that follows the change of pilot flow is caused by the occurrence of cavitation around the proportional poppet, and that fundamental characteristics of the developed valve remain unaffected by the occurrence of cavitation

  16. Design of hydraulic active stabilizer bar test platform based on dSPACE

    Directory of Open Access Journals (Sweden)

    Shan CHEN

    2016-12-01

    Full Text Available For the study of the influence of hydraulic active stabilizer bar to vehicle lateral stability under high speed steering maneuver, the hydraulic active stabilizer bar HIL test platform is implemented. The HIL test platform is designed with single/double axles universal test bench to experiment on single or double axles active stabilizer bar, using MC9S12DG128 microcontroller as the core controller and running vehicle dynamics model in the dSPACE. This HIL platform is used to study the effect of the hydraulic active stabilizer bar on the vehicle roll stability under different types of the road and typical steering maneuvers. The experiment results illustrate that the hydraulic active stabilizer bar HIL test platform can simulate the experiment environment and provide a powerful support for the development of active stabilizer bar system.

  17. Considerations on nominal and real content of active hydraulic materials in cements

    Directory of Open Access Journals (Sweden)

    Calleja, J.

    1966-06-01

    Full Text Available Not availableGran parte de las deficiencias y fallos de los conglomerados, además de las inherentes a defectos de ejecución no considerados en este trabajo, se deben, bien sea a dosificaciones bajas de conglomerante, o a empleo de conglomerantes inadecuados por su baja calidad. Por conglomerantes inadecuados se entiende aquí, no los que se ajustan por los valores de sus resistencias a la categoría más baja del P.C.C.H. 64, puesto que con los requisitos a ella exigidos ya cumplen, sino los obtenidos por "dilución" de clínkeres de buena o excelente calidad con materiales "inertes". Es mucho más nocivo y peligroso, desde el punto de vista de la calidad del conglomerado en todos los órdenes, emplear uno de estos conglomerantes "inadecuados" que utilizar una dosificación "real" menor que la "nominal", en condiciones comparables. Cuando se dan simultáneamente ambas circunstancias, los efectos perjudiciales pueden ser muy considerables.

  18. 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.

  19. Design Formulae for Hydraulic Stability and Structural Integrity of Dolos Breakwater Round-Heads

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Jensen, Jacob Birk; Liu, Z.

    1995-01-01

    A rational design of Dolos armour unit should incorporate both the hydraulic stability and the structural integrity. The previous tests performed by Aalborg University (AU) resulted in design formulae for the trunk of a 1:1.5 slope Dolos breakwater without superstructure including both...

  20. Probe interface design consideration. [for interplanetary spacecraft missions

    Science.gov (United States)

    Casani, E. K.

    1974-01-01

    Interface design between a probe and a spacecraft requires not only technical considerations but also management planning and mission analysis interactions. Two further aspects of importance are the flyby versus the probe trade-off, and the relay link design and data handling optimization.

  1. Four Major Considerations of a Business English Curriculum Design

    Institute of Scientific and Technical Information of China (English)

    GUO Jing

    2016-01-01

    Business English(BE)in China is developing in an amazing speed, yet no consensus on curriculum design is reached. This paper reviews the history of Business English development both in and out of China, and gives four major considerations of the curriculum design of Business English for BA level.

  2. 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.

  3. Research design considerations for chronic pain prevention clinical trials

    DEFF Research Database (Denmark)

    Gewandter, Jennifer S; Dworkin, Robert H; Turk, Dennis C

    2015-01-01

    Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations...... for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment...... element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have...

  4. Considerations in designing a centrifugal atomiser for metal powder production

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Y.Y. [Department of Engineering, The University of Liverpool, Liverpool L69 3GH (United Kingdom)]. E-mail: y.y.zhao@livepool.ac.uk

    2006-07-01

    In centrifugal atomisation for metal powder production, the key to the control of the particle sizes is the design of the atomiser. This paper studies the main issues concerned in designing a centrifugal atomiser and provides guidance on the selection of an electric motor, radius of atomiser, slope angle of atomiser wall and flow rate of cooling water. In the selection of the atomiser radius, the power and material constraints as well as the hydraulic jump radius need to be considered. A cup atomiser with a slope angle of 60-70{sup o} would result in small spray droplets and thus a fine powder. The water cooling system needs to be assessed by examining the heat flow in the solid metal layer and in the atomiser.

  5. Three dimensional considerations in thermal-hydraulics of helical cruciform fuel rods for LWR power uprates

    Energy Technology Data Exchange (ETDEWEB)

    Shirvan, Koroush, E-mail: kshirvan@mit.edu; Kazimi, Mujid S.

    2014-04-01

    Highlights: • We benchmarked the 4 × 4 helical cruciform fuel (HCF) bundle pressure drop experimental data with CFD. • We also benchmarked the 4 × 4 HCF mixing experimental data with CFD. • We derived new friction factors for PWR and BWR designs at PWR and BWR operating conditions from CFD. • We showed the importance of modeling the 3D conduction in HCF in steady state and transient conditions. - Abstract: In order to increase the power density of current and new light water reactor designs, the helical cruciform fuel (HCF) rods have been proposed. The HCF rod is equivalent to a thin cylindrical rod, with 4 fuel containing vanes, wrapped around it. The HCF rods increase the surface area to volume ratio of the fuel and enhance the inter-subchannel mixing due to their helical shape. The rods do not need supporting grids, as they are packed to periodically contact their neighbors along the flow direction, enabling a higher power density in the core. The HCF rods were reported to have the potential to uprate existing PWRs by 45% and BWRs by 20%. In order to quantify the mixing behavior of the HCF rods based on their twist pitch, experiments were previously performed at atmospheric pressures with single phase water in a 4 by 4 HCF and cylindrical rod bundles. In this paper, the experimental results on pressure drop and mixing are benchmarked with computational fluid dynamic (CFD) using steady state the Reynolds average Navier–Stokes (RANS) turbulence model. The sensitivity of the CFD approach to computational domain, mesh size, mesh shape and RANS turbulence models are examined against the experimental conditions. Due to the refined radial velocity profile from the HCF rods twist, the turbulence models showed little sensitivity to the domain. Based on the CFD simulations, the total pressure drops under the PWR and BWR conditions are expected to be about 10% higher than the values previously reported solely from an empirical correlation based on the

  6. Feed-pump hydraulic performance and design improvement, Phase I: research program design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Brown, W.H.; Gopalakrishnan, S.; Fehlau, R.; Thompson, W.E.; Wilson, D.G.

    1982-03-01

    As a result of prior EPRI-sponsored studies, it was concluded that a research program should be designed and implemented to provide an improved basis for the design, procurement, testing, and operation of large feed pumps with increased reliability and stability over the full range of operating conditions. This two-volume report contains a research plan which is based on a review of the present state of the art and which defines the necessary R and D program and estimates the benefits and costs of the program. The recommended research program consists of 30 interrelated tasks. It is designed to perform the needed research; to verify the results; to develop improved components; and to publish computer-aided design methods, pump specification guidelines, and a troubleshooting manual. Most of the technology proposed in the research plan is applicable to nuclear power plants as well as to fossil-fired plants. This volume contains appendixes on pump design, cavitation damage, performance testing, hydraulics, two-phase flow in pumps, flow stability, and rotor dynamics.

  7. RELIABILITY-BASED DESIGN AND ANALYSIS ON HYDRAULIC SYSTEM FOR SYNTHETIC RUBBER PRESS

    Institute of Scientific and Technical Information of China (English)

    Yao Chengyu; Zhao Jingyi

    2005-01-01

    To overcome the design limitations of traditional hydraulic control system for synthetic rubber press and such faults as high fault rate, low reliability, high energy-consuming and which always led to shutting down of post-treatment product line for synthetic rubber, brand-new hydraulic system combining with PC control and two-way cartridge valves for the press is developed, whose reliability is analyzed, reliability model of the hydraulic system for the press is established by analyzing processing steps, and reliability simulation of each step and the whole system is carried out by software MATLAB, which is verified through reliability test. The fixed time test has proved not that theory analysis is sound, but the system has characteristics of reasonable design and high reliability,and can lower the required power supply and operational energy cost.

  8. Robust Adaptive Backstepping Control Design for a Nonlinear Hydraulic-Mechanical System

    DEFF Research Database (Denmark)

    Choux, Martin; Karimi, Hamid Reza; Hovland, Geir

    2009-01-01

    converge to zero despite the uncertainties in the system according to the Barbalat lemma. The resulting controllers are able to take into account the interval uncertainties in Coulomb friction parameters and in the internal leakage parameters in the cylinders. Two adaptation laws are obtained by using......The complex dynamics that characterize hydraulic systems make it difficult for the control design to achieve prescribed goals in an efficient manner. In this paper, we present the design and analysis of a robust nonlinear controller for a nonlinear hydraulic-mechanical (NHM) system. The system...... consists of an electrohydraulic servo valve and two hydraulic cylinders. Specifically, by considering a part of the dynamics of the NHM system as a norm-bounded uncertainty, two adaptive controllers are developed based on the backstepping technique that ensure the tracking error signals asymptotically...

  9. OPTIMIZATION DESIGN OF HYDRAU-LIC MANIFOLD BLOCKS BASED ON HUMAN-COMPUTER COOPERATIVE GENETIC ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Feng Yi; Li Li; Tian Shujun

    2003-01-01

    Optimization design of hydraulic manifold blocks (HMB) is studied as a complex solid spatial layout problem. Based on comprehensive research into structure features and design rules of HMB, an optimal mathematical model for this problem is presented. Using human-computer cooperative genetic algorithm (GA) and its hybrid optimization strategies, integrated layout and connection design schemes of HMB can be automatically optimized. An example is given to testify it.

  10. Recent advances and design considerations in capping systems

    Energy Technology Data Exchange (ETDEWEB)

    DiPippo, G.J.; Monteleone, M.J. [Eckenfelder Inc., Mahwah, NJ (United States)

    1996-12-31

    Capping systems for solid and hazardous waste management facilities and remedial applications have changed significantly over the years. Early designs were virtually monolithic, with little specification of functional properties. The evolution of capping systems has continued and was hastened by the application of geosynthetics and the diligence of those working in the industry in understanding the design considerations for and performance of various capping materials. Capping systems continue to evolve particularly with respect to the application and understanding of the geosynthetic components. Today the design of an effective cap with a total thickness of two feet, or even less as is discussed further below, is possible. Yet much more work remains in various areas such as more precise means of assessing stability, the effects of strain softening, design using seismic considerations, and the like. This paper describes various recent advances in cap design. Three of these advances are covered in some detail; namely, geosynthetic clay layers, subdrainage design using high capacity geonets, and a thin cap section using direct asphalt overlay of geosynthetics for industrial site applications. Several other advances and design considerations are more briefly addressed to illustrate the breadth of the evolution of capping systems.

  11. Test Rig Design and Presentation for a Hydraulic Yaw System

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2013-01-01

    dynamics under real conditions. The behavior of the system is analyzed with regard to 20 years of operation. This is for example done by applying loads from different design load cases, e.g. normal turbulence, extreme turbulence and different fault scenarios on the turbine. The paper first presents...... an introduction with the current state of the art and problem description, followed by a system description, where the system is designed and dimensioned. Based on the design, results from the test rig are presented and analyzed. Finally a conclusion summing up the design, model and test results is given....

  12. Spectrum analysis on quality requirements consideration in software design documents.

    Science.gov (United States)

    Kaiya, Haruhiko; Umemura, Masahiro; Ogata, Shinpei; Kaijiri, Kenji

    2013-12-01

    Software quality requirements defined in the requirements analysis stage should be implemented in the final products, such as source codes and system deployment. To guarantee this meta-requirement, quality requirements should be considered in the intermediate stages, such as the design stage or the architectural definition stage. We propose a novel method for checking whether quality requirements are considered in the design stage. In this method, a technique called "spectrum analysis for quality requirements" is applied not only to requirements specifications but also to design documents. The technique enables us to derive the spectrum of a document, and quality requirements considerations in the document are numerically represented in the spectrum. We can thus objectively identify whether the considerations of quality requirements in a requirements document are adapted to its design document. To validate the method, we applied it to commercial software systems with the help of a supporting tool, and we confirmed that the method worked well.

  13. Use of hydraulic models to identify and resolve design isssues in FGD systems

    Energy Technology Data Exchange (ETDEWEB)

    Strock, T.W. [Babcock & Wilcox, Alliance, OH (United States); Gohara, W.F. [Babcock & Wilcox, Barberton, OH (United States)

    1995-06-01

    The hydraulics within a wet flue gas desulfurization (FGD) scrubber involve several complex two-phase gas/liquid interactions that directly affect the scrubber pressure drop, mist elimination efficiency, and the mass transfer process of SO{sub 2} removal. Current industrial efforts to develop cost effective, high-efficiency wet FGD scrubbers are focusing, in part, on the hydraulics. The development of an experimental approach and test facility for understanding and optimizing wet scrubber flow characteristics has been completed. Hydraulic models simulate full-scale units and allow the designer to view the gas/liquid flow interactions. Modeling procedures for downsizing the wet scrubber for the laboratory have been developed and validated with field data comparisons. A one-eighth scale hydraulic model has been used to study several FGD scrubber design issues. Design changes to reduce capital and operating cost have been developed and tested. Recently, the model was used to design a commercial, uniform flow, high gas velocity absorber for the next generation of FGD systems.

  14. Modeling and Optimal Design of 3 Degrees of Freedom Helmholtz Resonator in Hydraulic System

    Institute of Scientific and Technical Information of China (English)

    GUAN Changbin; JIAO Zongxia

    2012-01-01

    Three degrees of freedom (3-DOF) Helmholtz resonator which consists of three cylindrical necks and cavities connected in series (neck-cavity-ncck-cavity-neck-cavity) is suitable to reduce flow pulsation in hydraulic system.A novel lumped parameter model (LPM) of 3-DOF Helmholtz resonator in hydraulic system is developed which considers the viscous friction loss of hydraulic fluid in the necks.Applying the Newton's second law of motion to the equivalent mechanical model of the resonator,closed-form expression of transmission loss and resonance frequency is presented.Based on the LPM,an optimal design method which employs rotate vector optimization method (RVOM) is proposed.The purpose of the optimal design is to search the resonator's unknown parameters so that its resonance frequencies can coincide with the pump-induced flow pulsation harmonics respectively.The optimal design method is realized to design 3-DOF Helmholtz resonator for a certain type of aviation piston pump hydraulic system.The optimization result shows the feasibility of this method,and the simulation under optimum parameters reveals that the LPM can get the same precision as transfer matrix method (TMM).

  15. Monitoring Conceptual Development: Design Considerations of a Formative Feedback tool

    NARCIS (Netherlands)

    Berlanga, Adriana; Smithies, Alisdair; Braidman, Isobel; Wild, Fridolin

    2010-01-01

    Berlanga, A. J., Smithies, A., Braidman, I., & Wild, F. (2010, 15 September). Monitoring Conceptual Development: Design Considerations of a Formative Feedback Tool. Presentation at the Interactive Computer Aided Learning Conference (ICL 2010), Track on Computer-based Knowledge & Skill Assessment and

  16. Lunar Module Electrical Power System Design Considerations and Failure Modes

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    This slide presentation reviews the design and redesign considerations of the Apollo lunar module electrical power system. Included in the work are graphics showing the lunar module power system. It describes the in-flight failures, and the lessons learned from these failures.

  17. The Design Consideration for Game-Based Learning

    Science.gov (United States)

    Liang, Chaoyun; Lee, Yuan-Zone; Chou, Wen-Shou

    2010-01-01

    The integration of game playing with online education has recently become one of the most discussed issues in the e-learning field for its potentially positive impact on the development of related industries and on the social lives of young people. In this article, the authors propose a set of design considerations to assist game-based learning…

  18. Considerations in designing an evaluation system for adaptive delta management

    NARCIS (Netherlands)

    Hermans, L.M.; Maat, J.; Haasnoot, M.; Kwakkel, J.H.

    2014-01-01

    New planning approaches put new requirements on evaluation. A recent innovation in the water domain is adaptive delta management (ADM). ADM supports long-term planning in the face of uncertainty. This paper discusses the main considerations for the design of an evaluation system for ADM, departing f

  19. Design and Development of Hydraulic Disc Brake Systems for Well Servicing Rig Drawworks

    Institute of Scientific and Technical Information of China (English)

    Gao xiangqian; Zhou Yongxia

    1996-01-01

    @@ The conventional band brakes have been known to be important but also the most unlnerable part in servicing rig deawworks.. The failures in braking and releasing operations haven't well been avoided. There have evidently existed the problems of difficult operation and inconvenient maintenance in this connection. The use of power-assisted hydraulic cylinders or pneumatic cylinders can not meet the requirements of operations either. Since the late 1980s, we have cooperated with Shengli oilfields and others in the successful design and development of PST25 hydraulic disc brake systems for well servicing rig in a fully closed working state.

  20. FRF based position controller design through system identification for A hydraulic cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Hyoung Kyu; Kim, Dong Hwan [Dept. of Mechanical Design and Robot Engineering, Seoul National University of Science and Technology, Seoul (Korea, Republic of); Park, Jong Won [Reliability Assessment Center, Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2015-11-15

    In this study, we have focused on the design of a controller and an operating program for the operation of the hydraulic actuators used in a shaker. To control the motion of the shaker accurately, the position of each hydraulic cylinder should be controlled precisely even under an uncertain environment. For this purpose, we have suggested a control algorithm using an FRF (frequency response function) based control which senses the behavior of the actuator in advance, calculates a transfer function through the system identification method, and provides the final control input. The experimental results on the performance of this system were compared with that of a simple PID control algorithm.

  1. Design of a New Type of Distribution Valve for Hydraulic Breaker and Analysis of Energy Consumption

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Energy consumed by distribution valves causes an energy loss for the output energy of hydraulic breakers, which has a significant influence on its efficiency. A new type of distribution valve used for hydraulic breakers, designed to reduce energy consumption, is analyzed on the basis of the operating principle and energy loss of the current distribution valve. The new distribution valve adopts a cone valve and the optimization technique of unequal open degree for the valve port. Theoretical calculations and analyses have proven that the new distribution valve can reduce energy loss by 9.0127J, or energy consumption by 31%, during an impact cycle and the efficiency of the hydraulic breaker can be raised by 4.5%. It has the following characteristics: little leakage, little pressure loss and low energy consumption.

  2. AP600 design certification thermal hydraulics testing and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hochreiter, L.E.; Piplica, E.J.

    1995-09-01

    Westinghouse Electric Corporation, in conjunction with the Department of Energy and the Electric Power Research Institute, have been developing an advanced light water reactor design; the AP600. The AP600 is a 1940 Mwt, 600Mwe unit which is similar to a Westinghouse two-loop Pressurized Water Reactor. The accumulated knowledge on reactor design to reduce the capital costs, construction time, and the operational and maintenance cost of the unit once it begins to generate electrical power. The AP600 design goal is to maintain an overall cost advantage over fossil generated electrical power.

  3. Thermal hydraulic design and decay heat removal of a solid target for a spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Takenaka, N. [Department of Mechanical Engineering, Kobe University, Kobe (Japan)]. E-mail: takenaka@mech.kobe-u.ac.jp; Nio, D. [Hokkaido University, Sapporo (Japan); Kiyanagi, Y. [Hokkaido University, Sapporo (Japan); Mishima, K. [Kyoto University Research Reactor Institute, Kumatori (Japan); Kawai, M. [High Energy Accelerator Research Institute, Tsukuba (Japan); Furusaka, M. [High Energy Accelerator Research Institute, Tsukuba (Japan)

    2005-08-01

    Thermal hydraulic design and thermal stress calculations were conducted for a water-cooled solid target irradiated by a MW-class proton beam for a spallation neutron source. Plate type and rod bundle type targets were examined. The thickness of the plate and the diameter of the rod were determined based on the maximum and the wall surface temperature. The thermal stress distributions were calculated by a finite element method (FEM). The neutronics performance of the target is roughly proportional to its average density. The averaged densities of the designed targets were calculated for tungsten plates, tantalum-clad tungsten plates, tungsten rods sheathed by tantalum and Zircaloy and they were compared with mercury density. It was shown that the averaged density was highest for the tungsten plates and was high for the tantalum cladding tungsten plates, the tungsten rods sheathed by tantalum and Zircaloy in order. They were higher than or equal to that of mercury for the 1-2 MW proton beams. Tungsten target without the cladding or the sheath is not practical due to corrosion by water under irradiation condition. Therefore, the tantalum cladding tungsten plate already made successfully by HIP and the sheathed tungsten rod are the candidate of high performance solid targets. The decay heat of each target was calculated. It was low enough low compared to that of ISIS for the target without tantalum but was about four times as high as that of ISIS when the thickness of the tantalum cladding was 0.5 mm. Heat removal methods of the decay heat with tantalum were examined. It was shown that a special cooling system was required for the target exchange when tantalum was used for the target. It was concluded that the tungsten rod target sheathed with stainless steel or Zircaloy was the most reliable from the safety considerations and had similar neutronics performance to that of mercury.

  4. Thermal hydraulic design and decay heat removal of a solid target for a spallation neutron source

    Science.gov (United States)

    Takenaka, N.; Nio, D.; Kiyanagi, Y.; Mishima, K.; Kawai, M.; Furusaka, M.

    2005-08-01

    Thermal hydraulic design and thermal stress calculations were conducted for a water-cooled solid target irradiated by a MW-class proton beam for a spallation neutron source. Plate type and rod bundle type targets were examined. The thickness of the plate and the diameter of the rod were determined based on the maximum and the wall surface temperature. The thermal stress distributions were calculated by a finite element method (FEM). The neutronics performance of the target is roughly proportional to its average density. The averaged densities of the designed targets were calculated for tungsten plates, tantalum clad tungsten plates, tungsten rods sheathed by tantalum and Zircaloy and they were compared with mercury density. It was shown that the averaged density was highest for the tungsten plates and was high for the tantalum cladding tungsten plates, the tungsten rods sheathed by tantalum and Zircaloy in order. They were higher than or equal to that of mercury for the 1 2 MW proton beams. Tungsten target without the cladding or the sheath is not practical due to corrosion by water under irradiation condition. Therefore, the tantalum cladding tungsten plate already made successfully by HIP and the sheathed tungsten rod are the candidate of high performance solid targets. The decay heat of each target was calculated. It was low enough low compared to that of ISIS for the target without tantalum but was about four times as high as that of ISIS when the thickness of the tantalum cladding was 0.5 mm. Heat removal methods of the decay heat with tantalum were examined. It was shown that a special cooling system was required for the target exchange when tantalum was used for the target. It was concluded that the tungsten rod target sheathed with stainless steel or Zircaloy was the most reliable from the safety considerations and had similar neutronics performance to that of mercury.

  5. 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)

  6. Design considerations for energy efficient, resilient, multi-layer networks

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Hansen, Line Pyndt; Ruepp, Sarah Renée

    2016-01-01

    This work investigates different network design considerations with respect to energy-efficiency, under green-field resilient multi-layer network deployment. The problem of energy efficient, reliable multi-layer network design is known to result in different trade-offs between key performance...... in multi-layer networks and performance measures such as network resource utilization, availability, agility to traffic fluctuations and energy consumption. A green-field network deployment scenario is considered, where different resiliency methods, design methodologies and grooming strategies are applied...

  7. Design Considerations for a Flexible Multigrid Preconditioning Library

    Directory of Open Access Journals (Sweden)

    Jérémie Gaidamour

    2012-01-01

    Full Text Available MueLu is a library within the Trilinos software project [An overview of Trilinos, Technical Report SAND2003-2927, Sandia National Laboratories, 2003] and provides a framework for parallel multigrid preconditioning methods for large sparse linear systems. While providing efficient implementations of modern multigrid methods based on smoothed aggregation and energy minimization concepts, MueLu is designed to be customized and extended. This article gives an overview of design considerations for the MueLu package: user interfaces, internal design, data management, usage of modern software constructs, leveraging Trilinos capabilities, linear algebra operations and advanced application.

  8. Design for Additive Manufacturing: Trends, opportunities, considerations, and constraints

    DEFF Research Database (Denmark)

    Thompson, Mary Kathryn; Moroni, Giovanni; Vaneker, Tom

    2016-01-01

    The past few decades have seen substantial growth in Additive Manufacturing (AM) technologies. However, this growth has mainly been process-driven. The evolution of engineering design to take advantage of the possibilities afforded by AM and to manage the constraints associated with the technology...... has lagged behind. This paper presents the major opportunities, constraints, and economic considerations for Design for Additive Manufacturing. It explores issues related to design and redesign for direct and indirect AM production. It also highlights key industrial applications, outlines future...

  9. Development of guidelines for improved hydraulic design of waste stabilisation ponds.

    Science.gov (United States)

    Shilton, A; Harrison, J

    2003-01-01

    Pond hydraulic behaviour is influenced by the inlet/outlet configuration, baffles and wind, but design information relating to these factors is still very limited. This paper reviews the development of "Guidelines for the Improved Hydraulic Design of Waste Stabilisation Ponds" and summarises some of the key findings and recommendations. This work was based on review of previous research, laboratory experimentation, field studies and mathematical modelling using computational fluid dynamics. The inlet design can have a significant influence on the flow regime in a pond. Poorly considered positioning of the inlet and the outlet can create hydraulic short-circuiting problems. As an example of the nature of the work undertaken in this project, the use of a small horizontal inlet pipe was compared against a vertical inlet design. A practical method of assessing the relative significance of wind versus inlet power input was presented. The application of this analysis may allow engineers to size inlet pipes to help control the flow patterns in ponds for efficient performance. Extensive testing has been undertaken on a wide range of baffle configurations. An example of this research showed how short stub baffles could provide similar improvements to longer "traditional" baffle designs, potentially offering significant savings in construction costs. For traditional baffle designs a minimum of two baffles is recommended. For the pond modelled in this work, it was found that any more than four baffles gave only marginal improvements.

  10. A novel design of semi-active hydraulic mount with wide-band tunable notch frequency

    Science.gov (United States)

    Wang, Min; Yao, Guo-feng; Zhao, Jing-zhou; Qin, Min

    2014-04-01

    Hydraulic engine mount is advanced vibration isolator with superior performance to reduce vibration transferred from engine to chassis. As the stiffness at notch frequency is small, some semi-active or active hydraulic mounts tune some parameters to let notch frequency coincide with exciting frequency for better vibration isolation performance. It is discovered the current semi-active mounts can tune the notch frequency in narrow frequency band when only one parameter is tuned. A novel semi-active hydraulic engine mount design which introduces screw thread is proposed and researched in the paper. This hydraulic mount can control both cross section area and the length of inertia track and the theoretical tunable notch frequency band is [0, ∞). Theoretical work is carried out to uncover the capability for the proposed design to tune notch frequency. Simulation work is performed to understand its high vibration isolation performance. For the purpose of energy conservation, the friction self-locking is introduced. This denotes once the mount is tuned at optimal condition, the energy can be cut off and the optimal condition will never change. We also determine the best time to tune the parameters of the proposed mount in order to decrease the acting force. The proposed semi-active mount has capability to obtain wide band tunable notch frequency and has merit of energy conservation.

  11. Profile constructing and elevation design of soil reclaimed by hydraulic dredge pump in mining areas

    Energy Technology Data Exchange (ETDEWEB)

    Longqian, C.; Aiqin, S.; Tianjian, Z. [China Univ. of Mining and Technology, Xuzhou, Jiangsu (China). School of Environmental Science and Spatial Informatics; Mei, L. [China Univ. of Mining and Technology, Xuzhou, Jiangsu (China)

    2007-07-01

    Underground coal mining is the main method of coal mining in China. The hydraulic dredge pump reclamation method is the basic method used for repairing hydraulic erosion. This paper reviewed land reclamation by hydraulic dredge pump in the Yi'an coal mine of Xuzhou mining area in the east of China, and analyzed the constructing theory of soil profiling. It examined factors such as the height of the ground-water table; the thickness of plough horizon; the length of crops root and the state of soil erosion; and the methods of profile construction and elevation design of soil reclaimed by hydraulic dredge pump. A relevant mathematical model was also developed. The paper discussed the general situation of the study site as well as the basic theory of profile constructing and the profile constructing method. The paper also discussed the elevation design of the reclaimed land. It was concluded that the practice has proved that the methods can make the reclaimed soil keep a similar characteristics to that of original cropped soil, and meet the requirements for elevation of reclaimed land. 8 refs., 1 tab., 2 figs.

  12. Corps of Engineers Hydraulic Design Criteria. Volume I

    Science.gov (United States)

    1977-01-01

    Design Memorandum No. G-7, 1955. (10) Moore, M. 0., "Incrustation in water pipelines ." ASCE, Pipeline Di- vision, Journal, vol 94, PL 1, paper 6161...October 1968), pp 37-T7. 224 -1/1 Revised 6-57 Revised 1-64 Revised 9-70 Revised 3-73 (i)Franke, P. G., "Some roughness values of water pipelines ." L’Energia

  13. Designing of Hydraulically Balanced Water Distribution Network Based on GIS and EPANET

    Directory of Open Access Journals (Sweden)

    RASOOLI Ahmadullah

    2016-02-01

    Full Text Available The main objectives of this paper are, designing and balancing of Water Distribution Network (WDN based on loops hydraulically balanced method as well as using Geographical Information System (GIS methodology with the contribution of EPANET. GIS methodology is used to ensure WDN’s integrity and skeletonized a proper and functional WDN by using Network Analyst utilizing the geometric network and topology network by hierarchical geo-databases. The problem is to make WDN hydraulically balanced by applying WDN balancing method. For that reason, we have analyzed water flows in each pipe and performed the iterations process on loops in order to make the algebraic summation of head loss“h_f” around any closed loop zero. In case, the summation of pipe flows must be equal to the flow amount entering or leaving the system through each node. At each iteration, reasonable changes occurred at pipes flow until the head loss has become very small or fixed zero as (optimizes correction by using excel sheet solver. Since this method is confirmed to be effective, simulations were done by using GIS and EPANET water distribution platform. As a result, we accomplished hydraulically balanced WDN. Finally, we have analyzed and simulated hydraulics parameters for the targeted area in Kabul city. Thus, determined successfully the hydraulics state of parameters around the network as a positive result. It is worth mentioning that, Hardy-cross method is being used for approaching more precise optimized correction and consequences concerning hydraulically-balanced and optimal WDN. This method can be done for complex loops WDN as well; the advantage of the method is simple math and self-correction. Managers and engineers who work in the field of water supply this methodology has been recommended as the more advantageous workflow in planning water distribution pattern.

  14. Resolution of thermal-hydraulic safety and licensing issues for the system 80+{sup {trademark}} design

    Energy Technology Data Exchange (ETDEWEB)

    Carpentino, S.E.; Ritterbusch, S.E.; Schneider, R.E. [ABB-Combustion Engineering, Windsor, CT (United States)] [and others

    1995-09-01

    The System 80+{sup {trademark}} Standard Design is an evolutionary Advanced Light Water Reactor (ALWR) with a generating capacity of 3931 MWt (1350 MWe). The Final Design Approval (FDA) for this design was issued by the Nuclear Regulatory Commission (NRC) in July 1994. The design certification by the NRC is anticipated by the end of 1995 or early 1996. NRC review of the System 80+ design has involved several new safety issues never before addressed in a regulatory atmosphere. In addition, conformance with the Electric Power Research Institute (EPRI) ALWR Utility Requirements Document (URD) required that the System 80+ plant address nuclear industry concerns with regard to design, construction, operation and maintenance of nuclear power plants. A large number of these issues/concerns deals with previously unresolved generic thermal-hydraulic safety issues and severe accident prevention and mitigation. This paper discusses the thermal-hydraulic analyses and evaluations performed for the System 80+ design to resolve safety and licensing issues relevant to both the Nuclear Stream Supply System (NSSS) and containment designs. For the NSSS design, the Safety Depressurization System mitigation capability and resolution of the boron dilution concern are described. Examples of containment design issues dealing with containment shell strength, robustness of the reactor cavity walls and hydrogen mixing under severe accident conditions are also provided. Finally, the overall approach used in the application of NRC`s new (NUREG-1465) radiological source term for System 80+ evaluation is described. The robustness of the System 80+ containment design to withstand severe accident consequences was demonstrated through detailed thermal-hydraulic analyses and evaluations. This advanced design to shown to meet NRC severe accident policy goals and ALWR URD requirements without any special design features and unnecessary costs.

  15. NIF ReShock/Shear Photometrics Design Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Flippo, Kirk Adler [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-12

    The design of the photometrics for the NIF Shock/Shear campaign was driven by three linked considerations: the backlighter (BL) material had to be chosen such that it’s He-α emission line gave high enough contrast to measure mix width and see the shock propagation in the target wall, the BL beam geometry had to give sufficient BL spot dimensions and intensity to produce a uniform He-α radiograph of the target, and the BL/pinhole system had to have a high enough resolution and signal to be able to measure the quantities of interest. The design considerations are linked such that the required contrast determines the BL material, the BL material determines what laser intensity range is need for He-α emission, and the resulting He-α emission intensity helps determine whether or not there will be sufficient signal for analysis.

  16. Design considerations and operational performance of Anaerobic Digester: A Review

    Directory of Open Access Journals (Sweden)

    Muzaffar Ahmad Mir

    2016-04-01

    Full Text Available Due to the decline in fossil fuel reservoirs, the researchers emphasized more on the production of biogas from organic waste. Producing the renewable energy from biodegradable waste helps to overcome the energy crisis and solid waste management, done by anaerobic digestion. Anaerobic digestion is controlled breakdown of organic matter into methane gas (60%, carbon dioxide (40%, trace components along with digested used as soil conditioner. However there is vast dearth of literature regarding the design considerations. The batch digestion system yields a cost-effective and economically viable means for conversion of the food waste to useful energy. It is therefore recommended that such process can be increasingly employed in order to get and simultaneously protect the environment .This paper aims to draw key analysis and concern about the design considerations, analysis of gas production, substrates and inoculums utilization, uses and impacts of biogas.

  17. Biomechanics of injury prediction for anthropomorphic manikins - preliminary design considerations

    Energy Technology Data Exchange (ETDEWEB)

    Engin, A.E. [Univ. of South Alabama, Mobile, AL (United States)

    1996-12-31

    The anthropomorphic manikins are used in automobile safety research as well as in aerospace related applications. There is now a strong need to advance the biomechanics knowledge to determine appropriate criteria for injury likelihood prediction as functions of manikin-measured responses. In this paper, three regions of a manikin, namely, the head, knee joint, and lumbar spine are taken as examples to introduce preliminary design considerations for injury prediction by means of responses of theoretical models and strategically placed sensing devices.

  18. Stability and Ergonomic Design Features of Tractor Mounted Hydraulic Elevator for Coconut Harvesting

    Directory of Open Access Journals (Sweden)

    Kishor P. Kolhe

    2011-01-01

    Full Text Available Problem statement: The most important design criterion of mechanized device is safety; safety comprises both the safety of operator and safety of maintenance personnel. Failures and safety of harvesting platform of Tractor Mounted Hydraulic Elevator (TMHE powered by tractor PTO was tested by Finite Element Method for the mechanical harvesting of coconut orchards using digital Ergonomic hart rate meter. The objective of this study was to study the stability of the THME by finite element method, operational safety and power requirement for the use of this elevator for coconut harvesting. Also to provide sufficient adjustment and space to account for variation in body sizes, ensure controls are situated within suitable reach and are properly marked. Approach: The Modal analysis was carried out for the whole assembly of tractor mounted hydraulic elevator by using Ansis software. The digital polar hart rate meter RS400TM having infrared connectivity sensor is used for recording the hart rates. The research work was conducted at, Dr. Balasaheb Sawant Kokan Krishi Vidyapeeth Dapoli. The harvesting of coconuts was performed by manual climbing labor and by tractor mounted hydraulic elevator. The technical assessments included the use of biomechanical models, vibration testing equipment, ODR, BPDS. The ergonomical evaluation results of the above study are correlates to decide the feasibility, safety and efficiency of Tractor mounted hydraulic elevator for coconut harvesting. The PTO rpm influence for the lifting and lowering of the harvesting platform was studied experimentally by using digital tachometer. Results: The better stability results with the controlled vibrations and frequency of the lifting platform and welded joints were recorded by keeping constrained boundary conditions. Ergonomically operational safe and controlled heart rates are recorded. Hence the labors can continuously do the coconut harvesting work by using the tractor mounted

  19. The design considerations for a superconducting magnetic bearing system

    Science.gov (United States)

    Cansiz, Ahmet; Yildizer, Irfan

    2014-09-01

    In this paper a high temperature superconducting magnetic bearing is studied with various design considerations. The design of the bearing consists of a rotor with 7.5 kg mass. The stable levitation of the rotor is provided with the Evershed type and superconducting components. The dynamic stability of the rotor is strengthened with the electromagnetic and electrodynamic levitation techniques. The force on the rotor is predicted in terms of semi-analytical frozen image model. The designed driving system sustains stable levitation during the rotation of the rotor and achieves higher rotational speed than that of the torque driver. The results indicate that the designed rotor and driving system have potential solutions for the development of the superconducting flywheel energy storage.

  20. Lead Coolant Test Facility Systems Design, Thermal Hydraulic Analysis and Cost Estimate

    Energy Technology Data Exchange (ETDEWEB)

    Soli Khericha; Edwin Harvego; John Svoboda; Ryan Dalling

    2012-01-01

    The Idaho National Laboratory prepared a preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed: (1) Develop and Demonstrate Feasibility of Submerged Heat Exchanger; (2) Develop and Demonstrate Open-lattice Flow in Electrically Heated Core; (3) Develop and Demonstrate Chemistry Control; (4) Demonstrate Safe Operation; and (5) Provision for Future Testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimate. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

  1. Lead coolant test facility systems design, thermal hydraulic analysis and cost estimate

    Energy Technology Data Exchange (ETDEWEB)

    Khericha, Soli, E-mail: slk2@inel.gov [Battelle Energy Alliance, LLC, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Harvego, Edwin; Svoboda, John; Evans, Robert [Battelle Energy Alliance, LLC, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Dalling, Ryan [ExxonMobil Gas and Power Marketing, Houston, TX 77069 (United States)

    2012-01-15

    The Idaho National Laboratory prepared a preliminary technical and functional requirements (T and FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic coolant. Based on review of current world lead or lead-bismuth test facilities and research needs listed in the Generation IV Roadmap, five broad areas of requirements were identified as listed below: Bullet Develop and demonstrate feasibility of submerged heat exchanger. Bullet Develop and demonstrate open-lattice flow in electrically heated core. Bullet Develop and demonstrate chemistry control. Bullet Demonstrate safe operation. Bullet Provision for future testing. This paper discusses the preliminary design of systems, thermal hydraulic analysis, and simplified cost estimated. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 4200 Degree-Sign C. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M (in 2006 $). It is also estimated that the facility will require two years to be constructed and ready for operation.

  2. Design and Experimental Validation of Hydraulic Yaw System for Multi MW Wind Turbine

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2013-01-01

    environment. The model and the test rig are tested up against different design load cases and the results are compared. The experiments show that the model is valid for comparing the overall dynamics of the hydraulic yaw system. Based on the results it is concluded that the model derived is suitable......To comply with the increasing demands for life time and reliability of wind turbines as these grow in size, new measures needs to be taken in the design of wind turbines and components hereof. One critical point is the initial testing of the components and systems before they are implemented...... market. A hydraulic yaw system is such a new technology, and so a mathematical model of the full scale system and test rig system is derived and compared to measurements from the system. This is done in order to have a validated model, which wind turbine manufacturers may use for test in their simulation...

  3. Intelligent Stability Design of Large Underground Hydraulic Caverns: Chinese Method and Practice

    Directory of Open Access Journals (Sweden)

    Xiating Feng

    2011-10-01

    Full Text Available The global energy shortage has revived the interest in hydroelectric power, but extreme geological condition always pose challenges to the construction of hydroelectric power stations with large underground caverns. To solve the problem of safe design of large underground caverns, a Chinese-style intelligent stability design, representing recent developments in Chinese techniques for the construction of underground hydropower systems is presented. The basic aim of this method is to help designers improve the stability and design efficiency of large underground hydropower cavern groups. Its flowchart consists of two parts, one is initial design with an ordinal structure, and the other is dynamic design with a closed loop structure. In each part of the flowchart, analysis techniques, analysis content and design parameters for caverns’ stability are defined, respectively. Thus, the method provides designers with a bridge from the basic information of objective engineering to reasonable design parameters for managing the stability of hydraulic cavern groups. Application to two large underground caverns shows that it is a scientific and economical method for safely constructing underground hydraulic caverns.

  4. Effects of radial diffuser hydraulic design on a double-suction centrifugal pump

    Science.gov (United States)

    Hou, H. C.; Zhang, Y. X.; Xu, C.; Zhang, J. Y.; Li, Z. L.

    2016-05-01

    In order to study effects of radial diffuser on hydraulic performance of crude oil pump, the steady CFD numerical method is applied and one large double-suction oil pump running in long-distance pipeline is considered. The research focuses on analysing the influence of its diffuser vane profile on hydraulic performance of oil pump. The four different types of cylindrical vane have been designed by in-house codes mainly including double arcs (DA), triple arcs (TA), equiangular spiral line (ES) and linear variable angle spiral line (LVS). During design process diffuser vane angles at inlet and outlet are tentatively given within a certain range and then the wrapping angle of the four types of diffuser vanes can be calculated automatically. Under the given inlet and outlet angles, the linear variable angle spiral line profile has the biggest wrapping angle and profile length which is good to delay channel diffusion but bring more friction hydraulic loss. Finally the vane camber line is thickened at the certain uniform thickness distribution and the 3D diffuser models are generated. The whole flow passage of oil pump with different types of diffusers under various flow rate conditions are numerically simulated based on RNG k-ɛ turbulent model and SIMPLEC algorithm. The numerical results show that different types of diffusers can bring about great difference on the hydraulic performance of oil pump, of which the ES profile diffuser with its proper setting angle shows the best hydraulic performance and its inner flow field is improved obviously. Compared with the head data from model sample, all designed diffusers can make a certain improvement on head characteristic. At the large flow rate conditions the hydraulic efficiency increases obviously and the best efficiency point shift to the large flow rate range. The ES profile diffuser embodies the better advantages on pump performance which can be explained theoretically that the diffuser actually acts as a diffusion

  5. Advance of Study on Design Methods of Hydraulic System of Radio Remote Control of Construction Machinery

    Institute of Scientific and Technical Information of China (English)

    FENG Kai-lin; YANG Wei-min; CHEN kang-ning

    2003-01-01

    The working principle of radio remote controlling of construction machinery should be that signals of the radio wave from the transmitter obtained in the receiver were controlled and then changed into electronic analog or digital signals which can be used to drive different actuators and mechanisms of the vehicle.The vehicle could be acted by following the controlling instructions sent by the operator.The best operation mode of construction machinery is suitable not only to manual operating but also to remote controlling in the same vehicle.The design methods of the hydraulic system used for the radio remote controlling of construction machinery are discussed.The design methods of hydraulic circuits for the actuators controlled by solenoid on-off type valves,hydro-electronic multi-way proportional valves,closed loop proportional servo driver or three-way proportional reducing valves are discussed in detail (with real example).The design methods of the power shift transmission of electro-hydraulic controlling,the devices of braking and the directional streering are discussed in this paper.

  6. Design of a Resistively Heated Thermal Hydraulic Simulator for Nuclear Rocket Reactor Cores

    Science.gov (United States)

    Litchford, Ron J.; Foote, John P.; Ramachandran, Narayanan; Wang, Ten-See; Anghaie, Samim

    2007-01-01

    A preliminary design study is presented for a non-nuclear test facility which uses ohmic heating to replicate the thermal hydraulic characteristics of solid core nuclear reactor fuel element passages. The basis for this testing capability is a recently commissioned nuclear thermal rocket environments simulator, which uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce high-temperature pressurized hydrogen flows representative of reactor core environments, excepting radiation effects. Initially, the baseline test fixture for this non-nuclear environments simulator was configured for long duration hot hydrogen exposure of small cylindrical material specimens as a low cost means of evaluating material compatibility. It became evident, however, that additional functionality enhancements were needed to permit a critical examination of thermal hydraulic effects in fuel element passages. Thus, a design configuration was conceived whereby a short tubular material specimen, representing a fuel element passage segment, is surrounded by a backside resistive tungsten heater element and mounted within a self-contained module that inserts directly into the baseline test fixture assembly. With this configuration, it becomes possible to create an inward directed radial thermal gradient within the tubular material specimen such that the wall-to-gas heat flux characteristics of a typical fuel element passage are effectively simulated. The results of a preliminary engineering study for this innovative concept are fully summarized, including high-fidelity multi-physics thermal hydraulic simulations and detailed design features.

  7. Optimal Design and Hybrid Control for the Electro-Hydraulic Dual-Shaking Table System

    Directory of Open Access Journals (Sweden)

    Lianpeng Zhang

    2016-08-01

    Full Text Available This paper is to develop an optimal electro-hydraulic dual-shaking table system with high waveform replication precision. The parameters of hydraulic cylinders, servo valves, hydraulic supply power and gravity balance system are designed and optimized in detail. To improve synchronization and tracking control precision, a hybrid control strategy is proposed. The cross-coupled control using a novel based on sliding mode control based on adaptive reaching law (ASMC, which can adaptively tune the parameters of sliding mode control (SMC, is proposed to reduce the synchronization error. To improve the tracking performance, the observer-based inverse control scheme combining the feed-forward inverse model controller and disturbance observer is proposed. The system model is identified applying the recursive least squares (RLS algorithm and then the feed-forward inverse controller is designed based on zero phase error tracking controller (ZPETC technique. To compensate disturbance and model errors, disturbance observer is used cooperating with the designed inverse controller. The combination of the novel ASMC cross-coupled controller and proposed observer-based inverse controller can improve the control precision noticeably. The dual-shaking table experiment system is built and various experiments are performed. The experimental results indicate that the developed system with the proposed hybrid control strategy is feasible and efficient and can reduce the tracking errors to 25% and synchronization error to 16% compared with traditional control schemes.

  8. Experiences with the hydraulic design of the high specific speed Francis turbine

    Science.gov (United States)

    Obrovsky, J.; Zouhar, J.

    2014-03-01

    The high specific speed Francis turbine is still suitable alternative for refurbishment of older hydro power plants with lower heads and worse cavitation conditions. In the paper the design process of such kind of turbine together with the results comparison of homological model tests performed in hydraulic laboratory of ČKD Blansko Engineering is introduced. The turbine runner was designed using the optimization algorithm and considering the high specific speed hydraulic profile. It means that hydraulic profiles of the spiral case, the distributor and the draft tube were used from a Kaplan turbine. The optimization was done as the automatic cycle and was based on a simplex optimization method as well as on a genetic algorithm. The number of blades is shown as the parameter which changes the resulting specific speed of the turbine between ns=425 to 455 together with the cavitation characteristics. Minimizing of cavitation on the blade surface as well as on the inlet edge of the runner blade was taken into account during the design process. The results of CFD analyses as well as the model tests are mentioned in the paper.

  9. Analysis of the Advantages and Disadvantages of Special and Traditional Hydraulic Fixture Design%专用、传统液压夹具设计的优缺点辨析

    Institute of Scientific and Technical Information of China (English)

    周小蓉; 黄立东

    2012-01-01

    液压夹具是新型的工业设备。对于传统、专用的液压夹具的设计需要做出一定思考,才能为以后高效能液压夹具的设计更加科学。企业抓住了液压夹具的优缺点辨析,才能向着更加科学、高效的方向前进。%Hydraulic fixture device is a new type of industrial equipment.For the traditional,special hydraulic fixture design,there need certain considerations,so as to make later high performance hydraulic fixture design more scientific.Enterprises will develop toward more scientific,efficient direction if seizing the advantages and disadvantages of hydraulic fixture.

  10. DESIGN CONSIDERATIONS UPON PRODUCT END-OF-LIFE OPTIONS

    Directory of Open Access Journals (Sweden)

    BARSAN Lucian

    2016-11-01

    Full Text Available The paper presents some considerations about the necessity of evaluating the environmental impact of a product during its entire life. The present situation (economic, social and ecologic imposes solutions to reduce this impact as a result of an analysis performed during all stages of the life cycle. This paper focuses on design solutions with consequences in the last stage, the end-of-life. Reusing products, with, or without remanufacturing and recycling the materials from products that cannot be reused represent some options analysed in this paper. The end-of-life options should be known even from the beginning of the design process and should be included as design objectives or, at least as constrictions. Considering them as human needs would naturally include them in the requirements list.

  11. Forming-Precision-Driven Structure Design of Hydraulic Press:Methodology and Case Study

    Institute of Scientific and Technical Information of China (English)

    李艳聪; 张连洪; 何柏岩; 陈永亮; 张淳

    2015-01-01

    The structure stiffness of presses has great effects on the forming precision of workpieces, especially in near-net or net shape forming. Conventionally the stiffness specification of presses is empirically determined, re-sulting in poor designs with insufficient or over sufficient stiffness of press structures. In this paper, an approach for the structure design of hydraulic presses is proposed, which is forming-precision-driven and can make presses cost-effective by lightweight optimization. The approach consists of five steps:(1)the determination of the press stiff-ness specification in terms of the forming precision requirement of workpieces;(2)the conceptual design of the press structures according to the stiffness and workspace specifications, and the structure configuration of the press;(3)the prototype design of the press structures by equivalently converting the conceptual design to proto-types;(4)the selection of key structure parameters by sensitivity analysis of the prototype design; and(5)the opti-mization of the prototype design. The approach is demonstrated and validated through a case study of the structure design of a 100 MN hydraulic press.

  12. Design considerations for fume hoods for process plants.

    Science.gov (United States)

    Goodfellow, H D; Bender, M

    1980-07-01

    Proper design of fume hoods is a necessary requisite for a clean working environment for many industrial processes. Until recently, the design of these hoods has been rather a trial and error approach and not based on sound engineering design principles. Hatch Associates have developed and applied new techniques to establish hood parameters for different industrail processes. The paper reviews the developed techniques and illustrates practical application of these techniques to the solving of difficult and comples fume hood design and operating performance problems. The scope of the paper covers the following subject areas: definitions and general considerations: evaluation of volume and heat flow rates for emission sources; local capture of process emissions; remote capture of process emissions and case studies of fume hood applications. The purpose of the paper is to detail a coherent approach in the analysis of emission problems which will result in the development of an efficient design of a fume capture hood. An efficient fume hood can provide a safe working place as well as a clean external environment. Although the techniques can be applied to smaller sources, the case studies which will be examined will be for fume hoods in the flow design range of 50 000 CFM to +1 000 000 CFM.

  13. A Bayesian Chance-Constrained Method for Hydraulic Barrier Design Under Model Structure Uncertainty

    Science.gov (United States)

    Chitsazan, N.; Pham, H. V.; Tsai, F. T. C.

    2014-12-01

    The groundwater community has widely recognized the model structure uncertainty as the major source of model uncertainty in groundwater modeling. Previous studies in the aquifer remediation design, however, rarely discuss the impact of the model structure uncertainty. This study combines the chance-constrained (CC) programming with the Bayesian model averaging (BMA) as a BMA-CC framework to assess the effect of model structure uncertainty in the remediation design. To investigate the impact of the model structure uncertainty on the remediation design, we compare the BMA-CC method with the traditional CC programming that only considers the model parameter uncertainty. The BMA-CC method is employed to design a hydraulic barrier to protect public supply wells of the Government St. pump station from saltwater intrusion in the "1,500-foot" sand and the "1-700-foot" sand of the Baton Rouge area, southeastern Louisiana. To address the model structure uncertainty, we develop three conceptual groundwater models based on three different hydrostratigraphy structures. The results show that using the traditional CC programming overestimates design reliability. The results also show that at least five additional connector wells are needed to achieve more than 90% design reliability level. The total amount of injected water from connector wells is higher than the total pumpage of the protected public supply wells. While reducing injection rate can be achieved by reducing reliability level, the study finds that the hydraulic barrier design to protect the Government St. pump station is not economically attractive.

  14. Design Considerations For Blast Loads In Pressure Vessels.

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, E. A. (Edward A.); Nickell, Robert E.; Pepin, J. E. (Jason E.)

    2007-01-01

    Los Alamos National Laboratory (LANL), under the auspices of the U.S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA), conducts confined detonation experiments utilizing large, spherical, steel pressure vessels to contain the reaction products and hazardous materials from high-explosive (HE) events. Structural design and analysis considerations include: (a) Blast loading phase (i.e., impulsive loading); (b) Dynamic structural response; (c) Fragment (i.e., shrapnel) generation and penetration; (d) Ductile and non-ductile fracture; and (e) Design Criteria to ASME Code Sec. VIII, Div. 3, Impulsively Loaded Vessels. These vessels are designed for one-time-use only, efficiently utilizing the significant plastic energy absorption capability of ductile vessel materials. Alternatively, vessels may be designed for multiple-detonation events, in which case the material response is restricted to elastic or near-elastic range. Code of Federal Regulations, Title 10 Part 50 provides requirements for commercial nuclear reactor licensing; specifically dealing with accidental combustible gases in containment structures that might cause extreme loadings. The design philosophy contained herein may be applied to extreme loading events postulated to occur in nuclear reactor and non-nuclear systems or containments.

  15. Carbon Taxes: A Review of Experience and Policy Design Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Sumner, J.; Bird, L.; Smith, H.

    2009-12-01

    State and local governments in the United States are evaluating a wide range of policies to reduce carbon emissions, including, in some instances, carbon taxes, which have existed internationally for nearly 20 years. This report reviews existing carbon tax policies both internationally and in the United States. It also analyzes carbon policy design and effectiveness. Design considerations include which sectors to tax, where to set the tax rate, how to use tax revenues, what the impact will be on consumers, and how to ensure emissions reduction goals are achieved. Emission reductions that are due to carbon taxes can be difficult to measure, though some jurisdictions have quantified reductions in overall emissions and other jurisdictions have examined impacts that are due to programs funded by carbon tax revenues.

  16. Carbon Taxes. A Review of Experience and Policy Design Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Sumner, Jenny [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bird, Lori [National Renewable Energy Lab. (NREL), Golden, CO (United States); Smith, Hillary [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2009-12-01

    State and local governments in the United States are evaluating a wide range of policies to reduce carbon emissions, including, in some instances, carbon taxes, which have existed internationally for nearly 20 years. This report reviews existing carbon tax policies both internationally and in the United States. It also analyzes carbon policy design and effectiveness. Design considerations include which sectors to tax, where to set the tax rate, how to use tax revenues, what the impact will be on consumers, and how to ensure emissions reduction goals are achieved. Emission reductions that are due to carbon taxes can be difficult to measure, though some jurisdictions have quantified reductions in overall emissions and other jurisdictions have examined impacts that are due to programs funded by carbon tax revenues.

  17. 3D Blade Hydraulic Design Method of the Rotodynamic Multiphase Pump Impeller and Performance Research

    Directory of Open Access Journals (Sweden)

    Yongxue Zhang

    2014-02-01

    Full Text Available A hydraulic design method of three-dimensional blade was presented to design the blades of the rotodynamic multiphase pump. Numerical simulations and bench test were conducted to investigate the performance of the example impeller designed by the presented method. The results obtained from the bench test were in good agreement with the simulation results, which indicated the reasonability of the simulation. The distributions of pressure and gas volume fraction were analyzed and the results showed that the designed impeller was good for the transportation of mixture composed of gas and liquid. In addition, the advantage of the impeller designed by the presented method was suitable for using in large volume rate conditions, which were reflected by the comparison of the head performance between this three-dimensional design method and another one.

  18. Dynamics and design of a power unit with a hydraulic piston actuator

    Science.gov (United States)

    Misyurin, S. Yu.; Kreinin, G. V.

    2016-07-01

    The problem of the preselection of parameters of a power unit of a mechatronic complex on the basis of the condition for providing a required control energy has been discussed. The design of the unit is based on analysis of its dynamics under the effect of a special-type test conditional control signal. The specific features of the approach used are a reasonably simplified normalized dynamic model of the unit and the formation of basic similarity criteria. Methods of designing a power unit with a hydraulic piston actuator that operates in point-to-point and oscillatory modes have been considered.

  19. A Computational Model of Hydraulic Volume Displacement Drive

    Directory of Open Access Journals (Sweden)

    V. N. Pil'gunov

    2014-01-01

    Full Text Available The paper offers a computational model of industrial-purpose hydraulic drive with two hydraulic volume adjustable working chamber machines (pump and motor. Adjustable pump equipped with the pressure control unit can be run together with several adjustable hydraulic motors on the principle of three-phase hydraulic socket-outlet with high-pressure lines, drain, and drainage system. The paper considers the pressure-controlled hydrostatic transmission with hydraulic motor as an output link. It shows a possibility to create a saving hydraulic drive using a functional tie between the adjusting parameters of the pump and hydraulic motor through the pressure difference, torque, and angular rate of the hydraulic motor shaft rotation. The programmable logic controller can implement such tie. The Coulomb and viscous frictions are taken into consideration when developing a computational model of the hydraulic volume displacement drive. Discharge balance considers external and internal leakages in equivalent clearances of hydraulic machines, as well as compression loss volume caused by hydraulic fluid compressibility and deformation of pipe walls. To correct dynamic properties of hydraulic drive, the paper offers that in discharge balance are included the additional regulated external leakages in the open circuit of hydraulic drive and regulated internal leakages in the closed-loop circuit. Generalized differential equations having functional multipliers and multilinked nature have been obtained to describe the operation of hydraulic positioning and speed drive with two hydraulic volume adjustable working chamber machines. It is shown that a proposed computational model of hydraulic drive can be taken into consideration in development of LS («Load-Sensing» drives, in which the pumping pressure is tuned to the value required for the most loaded slave motor to overcome the load. Results attained can be used both in designing the industrial-purpose heavy

  20. Design Considerations for a Launch Vehicle Development Flight Instrumentation System

    Science.gov (United States)

    Johnson, Martin L.; Crawford, Kevin

    2011-01-01

    When embarking into the design of a new launch vehicle, engineering models of expected vehicle performance are always generated. While many models are well established and understood, some models contain design features that are only marginally known. Unfortunately, these analytical models produce uncertainties in design margins. The best way to answer these analytical issues is with vehicle level testing. The National Aeronautics and Space Administration respond to these uncertainties by using a vehicle level system called the Development Flight Instrumentation, or DFI. This DFI system can be simple to implement, with only a few measurements, or it may be a sophisticated system with hundreds of measurement and video, without a recording capability. From experience with DFI systems, DFI never goes away. The system is renamed and allowed to continue, in most cases. Proper system design can aid the transition to future data requirements. This paper will discuss design features that need to be considered when developing a DFI system for a launch vehicle. It will briefly review the data acquisition units, sensors, multiplexers and recorders, telemetry components and harnessing. It will present a reasonable set of requirements which should be implemented in the beginning of the program in order to start the design. It will discuss a simplistic DFI architecture that could be the basis for the next NASA launch vehicle. This will be followed by a discussion of the "experiences gained" from a past DFI system implementation, such as the very successful Ares I-X test flight. Application of these design considerations may not work for every situation, but they may direct a path toward success or at least make one pause and ask the right questions.

  1. Thermal-hydraulic design and transient evaluation of a small long-life HTR

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Ming [Harbin Engineering University, Nantong Street 145, 150001 Harbin (China); Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Kloosterman, Jan Leen, E-mail: j.l.kloosterman@tudelft.nl [Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)

    2013-02-15

    Highlights: ► We present the thermal-hydraulic evaluations of a small, long-life and block-type HTR using the DALTON/THERMIX code system. ► A cross section generation methodology is developed and verified for the diffusion calculations of the small HTR. ► The thermal-hydraulic characteristics of the small HTR during pressurized loss of forced-cooling incidents are compared with depressurized loss of forced-cooling ones. ► The thermal-hydraulic characteristics of a cylindrical core are compared with an annular one. ► Thermal power limit of the small HTR is investigated based on depressurized loss of forced-cooling incidents. -- Abstract: Small long-life high temperature gas-cooled reactors (HTRs) may provide electricity or heat for remote areas or industrial users in developed and/or developing countries. Moreover, small HTRs have advantages over large nuclear reactors of demonstrated inherent safety, transportability, modular construction, and flexible site selection. This paper presents the thermal-hydraulic evaluations of the U-Battery, which is a small, long-life and block-type HTR using the DALTON/THERMIX code system. The thermal-hydraulic characteristics of a cylindrical design and an annular design of the U-Battery were evaluated for loss of forced-cooling (LOFC) incidents including depressurized LOFC (DLOFC) and pressurized LOFC (PLOFC) incidents. The calculations show that the stronger natural circulation during the PLOFC makes the reactor core cool faster than during the DLOFC, flattens the radial solid temperature distribution, and transfers more heat from the hot regions (bottom and center of the reactor core) to cold regions (top and periphery of the reactor core). Although the natural circulation in the reactor core is so weak that it is neglected during the DLOFC, the decay heat is removed passively by conduction without any violation of the temperature limits for the 20 MWth U-Battery. The comparisons of the cylindrical and annular reactor

  2. Thermal Hydraulic design parameters study for severe accidents using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Chang Hyun; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Chang, Keun Sun [Sunmoon University, Asan (Korea, Republic of)

    1997-12-31

    To provide the information on severe accident progression is very important for advanced or new type of nuclear power plant (NPP) design. A parametric study, therefore, was performed to investigate the effect of thermal hydraulic design parameters on severe accident progression of pressurized water reactors (PWRs). Nine parameters, which are considered important in NPP design or severe accident progression, were selected among the various thermal hydraulic design parameters. The backpropagation neural network (BPN) was used to determine parameters, which might more strongly affect the severe accident progression, among nine parameters. For training, different input patterns were generated by the latin hypercube sampling (LHS) technique and then different target patterns that contain core uncovery time and vessel failure time were obtained for Young Gwang Nuclear (YGN) Units 3 and 4 using modular accident analysis program (MAAP) 3.0B code. Three different severe accident scenarios, such as two loss of coolant accidents (LOCAs) and station blackout (SBO), were considered in this analysis. Results indicated that design parameters related to refueling water storage tank (RWST), accumulator and steam generator (S/G) have more dominant effects on the progression of severe accidents investigated, compared to the other six parameters. 9 refs., 5 tabs. (Author)

  3. 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.

  4. 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.

  5. Hydraulic design and analysis of the saxo-type vertical axial turbine

    Energy Technology Data Exchange (ETDEWEB)

    Hofler, Edvard; Gale, Janez; Bergant, Anton

    2010-07-01

    The design of the blade geometry of a wind turbine is highly important as it influences the power generation. The aim of this study is to introduce a method for hydraulic design and analysis of the blade geometry of a highly specific speed runner of the Saxo-type double-regulated vertical axial turbine. The streamline curvature method (SCM) was used to develop four blade shapes which were analyzed with computational fluid dynamics (CFD) tools and the best one chosen in term of turbine efficiency and cavitational characteristics. Results demonstrated that the physical shape of the blade can be found for the design duty point in a rapid and transparent way by using the SCM method with no adjustments required to use the CFD methods. This study proved that the SCM design procedure developed herein can be used to accurately design runner blades.

  6. A Course on Operational Considerations in Wastewater Treatment Plant Design. Student Manual.

    Science.gov (United States)

    Stottler, Stag and Associates, San Antonio, TX.

    This manual was designed to furnish information for upgrading the design of wastewater treatment plant facilities and to serve as a resource for establishing criteria for upgrading these plants. The manual also furnishes information for modifying plant design to compensate for current organic and hydraulic overloads and/or to meet more stringent…

  7. Hydraulic design and pre-whirl regulation law of inlet guide vane for centrifugal pump

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new hydraulic design method of three-dimensional guide vane for centrifugal pump is proposed on the assumption that the fluid at the outlet of guide vane satisfies the uniform velocity moment condition.The geometry of blade is controlled by the distributed rule of blade angles along the meridional streamline which is described by a fourth-order polynomial.Experiment results demonstrate that the designed guide vane can overcome the drawback of two-dimensional guide vane,enlarge the high efficiency scope and improve the hydraulic performance of centrifugal pump on the off-design operation conditions.In comparison with the performance of the centrifugal pump without inlet guide vane,the peak value of efficiency can be enhanced by 2.13% after the three-dimensional guide vane was being installed.The three-dimensional entire flow field of the centrifugal pump with inlet guide vane is simulated,and the basic principle and mechanism of inlet guide vane pre-whirl regulation are analyzed.The validity of design method has been proved.

  8. Optimal design of the front linkage of a hydraulic excavator for multi-objective function

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Won; Jung, Seung Min; Kim, Jong Won [Seoul National University, Seoul (Korea, Republic of); Kim, Jin Uk [Doosan Infracore, Incheon (Korea, Republic of); Seo, Tae Won [Yeungnam University, Gyeongsan (Korea, Republic of)

    2014-08-15

    The workspace, working velocity, excavating force, and load capacity of a hydraulic excavator play critical roles in the performance of the excavator for various tasks. This paper presents an optimal design of the front linkage of an excavator to maximize the performances of several indices simultaneously. A multi-objective function is defined to increase the excavator's workspace, working velocity, excavating force, and load capacity simultaneously. The workspace is defined by using four geometrical indices and the working velocity is defined by the amount of time needed to perform one cycle composed of digging and dumping. The excavating force consists of two forces, and the load capacity is defined by using the minimum values of three types with specific operations. A total of 10 indices define objective function with each weight, and pin-points of the front linkage are the design parameters, including joint positions of links and hydraulic actuators. A two-step optimization procedure is considered based on a new method called the hybrid Taguchi-random coordinate search algorithm. The results indicate a 3.43% increase in performance relative to the initial design parameters of a commercial excavator. More specifically, the excavator's workspace, working velocity, excavating force, and load capacity increase by 5.55%, 0.14%, 5.46%, and 0.33%, respectively. These improved design parameters can be applied to next generation excavators.

  9. System Design Considerations In Bar-Code Laser Scanning

    Science.gov (United States)

    Barkan, Eric; Swartz, Jerome

    1984-08-01

    The unified transfer function approach to the design of laser barcode scanner signal acquisition hardware is considered. The treatment of seemingly disparate system areas such as the optical train, the scanning spot, the electrical filter circuits, the effects of noise, and printing errors is presented using linear systems theory. Such important issues as determination of depth of modulation, filter specification, tolerancing of optical components, and optimi-zation of system performance in the presence of noise are discussed. The concept of effective spot size to allow for impact of optical system and analog processing circuitry upon depth of modulation is introduced. Considerations are limited primarily to Gaussian spot profiles, but also apply to more general cases. Attention is paid to realistic bar-code symbol models and to implications with respect to printing tolerances.

  10. Design of A Hydraulic Power Take-off System for the Wave Energy Device with An Inverse Pendulum

    Institute of Scientific and Technical Information of China (English)

    张大海; 李伟; 赵海涛; 鲍经纬; 林勇刚

    2014-01-01

    This paper describes a dual-stroke acting hydraulic power take-off (PTO) system employed in the wave energy converter (WEC) with an inverse pendulum. The hydraulic PTO converts slow irregular reciprocating wave motions to relatively smooth, fast rotation of an electrical generator. The design of the hydraulic PTO system and its control are critical to maximize the generated power. A time domain simulation study and the laboratory experiment of the full-scale beach test are presented. The results of the simulation and laboratory experiments including their comparison at full-scale are also presented, which have validated the rationality of the design and the reliability of some key components of the prototype of the WEC with an inverse pendulum with the dual-stroke acting hydraulic PTO system.

  11. Climate Changes and their Influence on the Design of Hydraulic Structures from Romania

    Directory of Open Access Journals (Sweden)

    Florin Trofin

    2013-09-01

    Full Text Available During the last decades, the human being influenced environmentally the Earth, causing global environmental changes of such a size that have become global phenomena. These changes include the climate, ozone layer depletion, biogeochemical cycles, hydrological cycle, and water resources, raising the ocean levels or thermohaline circulation. The hydrological cycle and water resources changes have significant effects on the design of hydraulic structures, provided they are exploited in the presence or absence of major climatic factors, such as water, air, or soil.

  12. Mechatronic System Design and Intelligent Motion Control of Hydraulic Robots and Machines

    DEFF Research Database (Denmark)

    Conrad, Finn; Sørensen, Torben

    2003-01-01

    The paper presents an approach and concept to mechatronic system design and intelligent motion control. The Information Technology (IT) offers software and hardware for improvement of R&D Mechatronic Teams to create products and solutions for industrial applications. The latest progress in IT makes...... control as well as from the Esprit project SWING on IT-tools for rapid prototyping of fluid power components and systems. A mechatronic test facility for a DTU-AAU hydraulic robot ¿Thor¿, and a CNC XY-machine table was implemented. The controller applies digital signal processors (DSPs). The DSP...

  13. DESIGNING HYDRAULIC AIR CHAMBER IN WATER TRANSMISSION SYSTEMS USING GENETIC ALGORITHM

    Directory of Open Access Journals (Sweden)

    Abdorahim Jamal

    2016-09-01

    Full Text Available Transient flow control in Water Transmission Systems (WTS is one of the requirements of designing these systems. Hence, among control equipment, air chambers offer the best solution to control transient flow effects, i.e. both prevents water column separation and absorbs pressure increase. It is essential to carry out an accurate and optimized design of air chambers, not only due to high costs of their manufacturing but also their important protective role. Accordingly, hydraulic design parameters comprise tank volume, diameter of nozzle and coefficients of inflow and outflow of nozzle. In this paper, it is intended to optimize these parameters in order to minimize manufacturing costs. On the other hand, maximum and minimum pressures in main pipeline are considered as constraints which shall fall in allowed range. Therefore, a model has been developed which is a combination of a hydraulic simulation model of WTS and an optimization model based on genetic algorithm. This model is first applied to WTS of Dehgolan-Ghorveh plain as a case study. Results of this research demonstrate that based on suggested model, negative wave creation and pressure increase in pipeline is prevented as well as decrease in manufacturing costs of air chamber.

  14. 远洋船用伸缩折叠起重机液压系统设计%Marine telescopic folding crane hydraulic system design

    Institute of Scientific and Technical Information of China (English)

    卢志珍; 倪学虎; 舒希勇; 王成龙

    2012-01-01

    在分析伸缩折叠起重机对液压系统要求的基础上,针对起重机技术参数及客户要求提出了液压系统设计的思路.对关键液压元件——液压泵、液压马达、液压缸进行了计算选型,设计了液压原理图,并阐述了起重机液压回路的工作原理.%Based on the analysis of telescopic folding crane hydraulic system requirements,put forward the hydraulic system design thinking according to crane technical parameters and requirements of customers. Calculation and type selection of the key hydraulic components------hydraulic pump and hydraulic motor, hydraulic cylinder, design hydraulic principle diagram and expoundscrane hydraulic loop principle of work.

  15. Design considerations for joints in deployable space truss structures

    Science.gov (United States)

    Rhodes, Marvin D.

    1986-01-01

    All of the structures considered for the Control of Flexible Structures (COFS) flight experiments are deployable truss structures and their response will be dominated by the structural response of the joints. To prepare for these experiments some fundamental research work is being conducted in the Structures and Dynamics Division at LaRC which will provide insight into structurally efficient and predictable deployable truss joints. This work involves generic studies of the static and dynamic response of joints as well as the development of analytical models which can be used to predict the response of a large multijointed truss. In addition to the generic joint studies, the research effort encompasses the design and fabrication of a 20-meter long deployable truss beam for laboratory evaluation of its structural characteristics and correlation with developed prediction methods. The experimental results have indicated the importance of attention to detail in the design and fabrication of joints for deployable truss structures. The dimensional relations and material considerations for efficient pin-clevis joints have been outlined. Results of tests on the near-center latch are discussed.

  16. Standard guide for general design considerations for hot cell equipment

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 Intent: 1.1.1 The intent of this guide is to provide general design and operating considerations for the safe and dependable operation of remotely operated hot cell equipment. Hot cell equipment is hardware used to handle, process, or analyze nuclear or radioactive material in a shielded room. The equipment is placed behind radiation shield walls and cannot be directly accessed by the operators or by maintenance personnel because of the radiation exposure hazards. Therefore, the equipment is operated remotely, either with or without the aid of viewing. 1.1.2 This guide may apply to equipment in other radioactive remotely operated facilities such as suited entry repair areas, canyons or caves, but does not apply to equipment used in commercial power reactors. 1.1.3 This guide does not apply to equipment used in gloveboxes. 1.2 Applicability: 1.2.1 This guide is intended for persons who are tasked with the planning, design, procurement, fabrication, installation, or testing of equipment used in rem...

  17. Non-linear hydraulic properties of woodchips necessary to design denitrification beds

    Science.gov (United States)

    Ghane, Ehsan; Feyereisen, Gary W.; Rosen, Carl J.

    2016-11-01

    Denitrification beds are being used to reduce the transport of water-soluble nitrate via subsurface drainage systems to surface water. Only recently has the non-linearity of water flow through woodchips been ascertained. To successfully design and model denitrification beds with optimum nitrate removal, a better understanding of flow in denitrification beds is needed. The main objectives of this study were to characterize the hydraulic properties of old degraded woodchips and provide a better understanding of the factors affecting flow. To achieve this goal, we conducted constant-head column experiments using old woodchips that were excavated from a four-year old denitrification bed near Willmar, Minnesota, USA. For Izbash's equation, the non-Darcy exponent (n) ranged from 0.76 to 0.87 that indicates post-linear regime, and the permeability coefficient (M10) at 10°C ranged from 0.9 to 2.6 cm s-1. For Forchheimer's equation, the intrinsic permeability of 5.6 × 10-5 cm2 and ω constant of 0.40 (at drainable porosity of 0.41) closely resembled the in-situ properties found in a previous study. Forchheimer's equation was better than that of Izbash's for describing water flow through old woodchips, and the coefficients of the former provided stronger correlations with drainable porosity. The strong correlation between intrinsic permeability and drainable porosity showed that woodchip compaction is an important factor affecting water flow through woodchips. Furthermore, we demonstrated the importance of temperature effects on woodchip hydraulics. In conclusion, the hydraulic properties of old woodchips should be characterized using a non-Darcy equation to help design efficient systems with optimum nitrate removal.

  18. Optimal design of hydraulic manifold blocks based on niching genetic simulated annealing algorithm

    Institute of Scientific and Technical Information of China (English)

    Jia Chunqiang; Yu Ling; Tian Shujun; Gao Yanming

    2007-01-01

    To solve the combinatorial optimization problem of outer layout and inner connection integrated schemes in the design of hydraulic manifold blocks(HMB),a hybrid genetic simulated annealing algorithm based on niche technology is presented.This hybrid algorithm,which combines genetic algorithm,simulated annealing algorithm and niche technology,has a strong capability in global and local search,and all extrema can be found in a short time without strict requests for preferences.For the complex restricted solid spatial layout problems in HMB,the optimizing mathematical model is presented.The key technologies in the integrated layout and connection design of HMB,including the realization of coding,annealing operation and genetic operation,are discussed.The framework of HMB optimal design system based on hybrid optimization strategy is proposed.An example is given to testify the effectiveness and feasibility of the algorithm.

  19. Quasi-experimental designs in practice-based research settings: design and implementation considerations.

    Science.gov (United States)

    Handley, Margaret A; Schillinger, Dean; Shiboski, Stephen

    2011-01-01

    Although randomized controlled trials are often a gold standard for determining intervention effects, in the area of practice-based research (PBR), there are many situations in which individual randomization is not possible. Alternative approaches to evaluating interventions have received increased attention, particularly those that can retain elements of randomization such that they can be considered "controlled" trials. Methodological design elements and practical implementation considerations for two quasi-experimental design approaches that have considerable promise in PBR settings--the stepped-wedge design, and a variant of this design, a wait-list cross-over design, are presented along with a case study from a recent PBR intervention for patients with diabetes. PBR-relevant design features include: creation of a cohort over time that collects control data but allows all participants (clusters or patients) to receive the intervention; staggered introduction of clusters; multiple data collection points; and one-way cross-over into the intervention arm. Practical considerations include: randomization versus stratification, training run in phases; and extended time period for overall study completion. Several design features of practice based research studies can be adapted to local circumstances yet retain elements to improve methodological rigor. Studies that utilize these methods, such as the stepped-wedge design and the wait-list cross-over design, can increase the evidence base for controlled studies conducted within the complex environment of PBR.

  20. Design consideration for design a flat and ring plastics part using Solidworks software

    Science.gov (United States)

    Amran, M. A. M.; Faizal, K. M.; Salleh, M. S.; Sulaiman, M. A.; Mohamad, E.

    2015-12-01

    Various considerations on design of plastic injection moulded parts were applied in initial stage to prevent any defects of end products. Therefore, the objective of this project is to design the plastic injection moulded part by taking consideration on several factors such as draft angle, corner radius and location of gate. In this project, flat plastic part, ring plastic part, core inserts for flat and ring plastic part were designed using SolidWorks software. The plastic part was drawn in sketching mode then the 3D modeling of solid part was generated using various commands. Considerations of plastic part such as draft angle and corner radius with location of gate was considered in the design stage. Finally, it was successfully designed the two plastic parts with their respectively insert by using SolidWorks software. The flat plastic part and ring plastic part were designed for the purpose for future researches for study the weld lines, meld lines, air trapped and geometrical size of the product. Thus, by designing the flat plastic part and ring plastic part having core insert on each part, the completed mould design of two plate mould can be considered. This is because, plastic injection parts are needed to be designed properly in order to neglect any defect when the mould was made.

  1. Thermal-hydraulic performance analysis for the conceptual design of Korean HCCR TBMset

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Won; Jin, Hyung Gon; Lee, Eo Hwak; Yoon, Jae Sung; Kim, Suk Kwon [KAERI, Daejeon (Korea, Republic of); Shin, Kyu In [Gentec Co., Daejeon (Korea, Republic of); Cho, Seungyon [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The purpose of this document is to provide the thermal-hydraulic (TH) analyses results of the Helium Cooled Ceramic Reflector (HCCR) Test Blanket Module (TBM) including TBM-shield, which is called TBM-set. The analyses were performed for Electro- Magnetic Module (EM-TBM) and INTegral Module (INT-TBM) including TBM-shield, respectively, with the same model and meshes according to the ITER operation conditions of H/He and D-T phases, respectively. Thermal-hydraulic performance of the EM- and INTTBM- sets were analysed using the fixed CATIA model for CDR. Fine mesh with 15.9 million elements for solid and 44.7 million elements for fluid was used for ANSYS-CFX 14.5 simulation and coarse mesh with 7.6 million elements for solid is prepared for the thermomechanical analysis. The boundary conditions such as heat flux, nuclear heating, and coolant conditions were determined considering the ITER operation condition and designed cooling scheme. The analysis results and conclusions are as follows; (1) It is confirmed that both EM- and INT-TBM performance results meet the design requirements, which were determined by the material characteristics. (2) The temperature results with fine mesh of both EMand INT-TBM-sets were successfully transferred to those of coarse mesh for the thermo-mechanical analysis.

  2. Quasi-three dimensional hydraulic design and performance calculation of high specific speed mixed-flow pump

    Science.gov (United States)

    Su, M.; Zhang, Y. X.; Zhang, J. Y.; Hou, H. C.

    2016-05-01

    According to the basic parameters of 211-80 high specific speed mixed-flow pump, based on the quasi-three dimensional flow theory, the hydraulic design of impeller and its matching spaced guide vanes for high specific speed mixed flow pump was completed, in which the iterative calculation of S 1, S 2 stream surfaces was employed to obtain meridional flow fields and the point-by-point integration method was employed to draw blade camber lines. Blades are thickened as well as blade leading edges are smoothed in the conformal mapping surface. Subsequently the internal fields of the whole flow passage of the designed pump were simulated by using RANS equations with RNG k-ε two-equation turbulent model. The results show that, compared with the 211-80 model, the hydraulic efficiency of the designed pump at the optimal flow rate increases 9.1%. The hydraulic efficiency of designed pump in low flow rate condition (78% designed flow rate) increases 6.46%. The hydraulic efficiency in high flow rate areas increases obviously and there is no bad phenomenon of suddenly decrease of hydraulic efficiency in model pump. From the distributions of velocity and pressure fields, it can be seen that the flow in impeller is uniform and the increase of pressure is gentle. There are no obvious impact phenomenon on impeller inlet and obvious wake shedding vortex phenomenon from impeller outlet to guide vanes inlet.

  3. Lunar Module Wiring Design Considerations and Failure Modes

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    This slide presentation reviews the considerations for the design of wiring for the Lunar Module. Included are a review of the choice of conductors and insulations, the wire splicing (i.e., crimping, and soldering), the wire connectors, and the fabrication of the wire harnesses. The problems in fabrication include the wires being the wrong length, the damage due to the sharp edges, the requried use of temproary protective covers and inadequate training. The problems in the wire harness installation include damge from sharp eges, work on adjacent harnesses, connector damage, and breaking wires. Engineering suggestions from the Apollo-era in reference to the conductors that are reviewed include: the use of plated conductors, and the use of alloys for stronger wiring. In refernce to insulation, the suggestions from Apollo era include the use of polymer tape-wrap wire insulation due to the light weight, however, other types of modern insulation might be more cost-effective. In reference to wire splices and terminal boards the suggestions from the Apollo Era include the use of crimp splices as superior to solder splices, joining multiple wire to a common point using modular plug-ins might be more reliable, but are heavier than crimp splicing. For connectors, the lessons from the Apollo era indicate that a rear environmental seal that does not require additional potting is preferred, and pins should be crimped or welded to the incoming wires and be removable from the rear of the connector.

  4. Energy-harvesting laser phosphor display and its design considerations

    Science.gov (United States)

    Fujieda, Ichiro; Itaya, Shunsuke; Ohta, Masamichi; Hirai, Yuuki; Kohmoto, Takamasa

    2017-04-01

    One can convert a luminescent solar concentrator to a display by projecting intensity-modulated light on it. We fabricated a 95 mm×95 mm×10 mm screen by sandwiching a thin coumarin 6 layer with two acrylic plates. We removed the light source in a commercial projector and fed a blue laser beam into its optics. It displayed monochrome images on the screen clearly. A photodiode covered a 10 mm×10 mm region on the edge surface of the screen. As we pulsed the laser, the photodiode output varied synchronously. Its output indicates that a fully covered version would harvest up to 71% of the incoming laser power. However, a ghost image was noticeable when we displayed a high-contrast still image. We address two aspects in design considerations. First, tiling small modules will reduce the thickness of a large-area projection system and alleviate its self-absorption loss. For seamless tiling, we can attach output couplers to the surface of the transparent plate and extract photoluminescence (PL) photons in each module. Second, the origin of the ghost image is the PL photons reflected at the plate-air interface inside the screen. Thinning the transparent plate facing the projector will eliminate such an optical cross talk.

  5. Completion Design Considerations for a Horizontal Enhanced Geothermal System

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Jeffrey; Eustes, Alfred; Fleckenstein, William; Eker, Erdinc; Baker, Reed; Augustine, Chad

    2015-09-02

    The petroleum industry has had considerable success in recent decades in developing unconventional shale plays using horizontal drilling and multi-zonal isolation and stimulation techniques to fracture tight formations to enable the commercial production of oil and gas. Similar well completions could be used in Enhanced Geothermal Systems (EGS) to create multiple fractures from horizontal wells. This study assesses whether well completion techniques used in the unconventional shale industry to create multi-stage fractures can be applied to an enhanced geothermal system, with a focus on the completion of the EGS injection well. This study assumes an Enhanced Geothermal System (EGS) consisting of a central horizontal injection well flanked on each side by horizontal production wells, connected to the injection well by multiple fractures. The focus is on the design and completion of the horizontal well. For the purpose of developing design criteria, a reservoir temperature of 200 degrees C (392 degrees F) and an injection well flow rate of 87,000 barrels per day (160 kg/s), corresponding to production well flow rates of 43,500 barrels per day (80 kg/s) is assumed. The analysis found that 9-5/8 inches 53.5 pounds per foot (ppf) P110 casing string with premium connections meets all design criteria for the horizontal section of injection well. A P110 grade is fairly common and is often used in horizontal sections of shale development wells in petroleum operations. Next, several zonal isolation systems commonly used in the shale gas industry were evaluated. Three techniques were evaluated -- a 'plug and perf' design, a 'sand and perf' design, and a 'packer and port' design. A plug and perf system utilizes a cemented casing throughout the length of the injector wellbore. The sand and perf system is identical to the plug and perf system, but replaces packers with sand placed in the casing after stimulation to screen out the stimulated

  6. Design of a Magnetostrictive-Hydraulic Actuator Considering Nonlinear System Dynamics and Fluid-Structure Coupling

    Science.gov (United States)

    Larson, John Philip

    Smart material electro-hydraulic actuators (EHAs) utilize fluid rectification via one-way check valves to amplify the small, high-frequency vibrations of certain smart materials into large motions of a hydraulic cylinder. Although the concept has been demonstrated in previously, the operating frequency of smart material EHA systems has been limited to a small fraction of the available bandwidth of the driver materials. The focus of this work is to characterize and model the mechanical performance of a magnetostrictive EHA considering key system components: rectification valves, smart material driver, and fluid-system components, leading to an improved actuator design relative to prior work. The one-way valves were modeled using 3-D finite element analysis, and their behavior was characterized experimentally by static and dynamic experimental measurement. Taking into account the effect of the fluid and mechanical conditions applied to the valves within the pump, the dynamic response of the valve was quantified and applied to determine rectification bandwidth of different valve configurations. A novel miniature reed valve, designed for a frequency response above 10~kHz, was fabricated and tested within a magnetostrictive EHA. The nonlinear response of the magnetostrictive driver, including saturation and hysteresis effects, was modeled using the Jiles-Atherton approach to calculate the magnetization and the resulting magnetostriction based on the applied field calculated within the rod from Maxwell's equations. The dynamic pressure response of the fluid system components (pumping chamber, hydraulic cylinder, and connecting passages) was measured over a range of input frequencies. For the magnetostrictive EHA tested, the peak performance frequency was found to be limited by the fluid resonances within the system. A lumped-parameter modeling approach was applied to model the overall behavior of a magnetostrictive EHA, incorporating models for the reed valve response

  7. Direct Drive Electro-hydraulic Servo Control System Design with Self-Tuning Fuzzy PID Controller

    Directory of Open Access Journals (Sweden)

    Wang Yeqin

    2013-06-01

    Full Text Available According to the nonlinear and time-varying uncertainty characteristics of direct drive electro-hydraulic servo control system, a self-tuning fuzzy PID control method with speed change integral and differential ahead optimizing operator is put forward by combining fuzzy inference and traditional PID control in this paper.The rule of fuzzy logic is designed, the membership function of the fuzzy subsets is determined and lookup table method is used to correcte the PID parameters in real-time. Finally the simulation is conducted with the typical input signal, such as tracking step, sine etc. The simulation results show that,the self-tuning fuzzy PID control system can effectively improve the dynamic characteristic when the system is out of the range of the operating point compared with the traditional PID control system, there is obvious improvement in the indexes of rapidity, stability and accuracy,  and fuzzy self-tuning PID Control is more robust, and more suitable for direct drive electro-hydraulic servo system.

  8. Dynamic Analysis and Design Optimization of Series Hydraulic Hybrid System through Power Bond Graph Approach

    Directory of Open Access Journals (Sweden)

    R. Ramakrishnan

    2014-01-01

    Full Text Available The availability of natural gas and crude oil resources has been declining over the years. In automobile sector, the consumption of crude oil is 63% of total crude oil production in the world. Hence, automobile industries are placing more emphasis on energy efficient hydraulic hybrid systems, which can replace their conventional transmission systems. Series hydraulic hybrid system (SHHS is a multidomain mechatronics system with two distinct power sources that includes prime mover and hydropneumatic accumulator. It replaces the conventional transmission system to drive the vehicle. The sizing of the subsystems in SHHS plays a major role in improving the energy efficiency of the vehicle. In this paper, a power bond graph approach is used to model the dynamics of the SHHS. The obtained simulation results indicate the energy flow during various modes of operations. It also includes the dynamic response of hydropneumatic accumulator, prime mover, and system output speed. Further, design optimization of the system is carried out to optimize the process parameters for maximizing the system energy efficiency. This leads to increase in fuel economy and environmentally friendly vehicle.

  9. Preliminary Design of Large Scale Sodium Thermal-Hydraulic Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae Ho; Kim, Tae Joon; Eoh, Jae Hyuk; Lee, Hyeong Yeon; Lee, Jae Han; Jeong, Ji Young; Park, Su Ki; Han, Ji Woong; Yoo, Yong Hwan; Lee, Yong Bum [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-10-15

    A large scale sodium thermal-hydraulic test facility is being designed for verification of the advanced design concept of the passive decay heat removal circuit (PDRC) in a medium- or large-sized pool-type SFR. In the test, its cooling capability during the long- and short-term periods after the reactor trip will be evaluated, and also the produced experimental data will be utilized for the assessment and verification of the safety and performance analysis codes. Starting with the preliminary design of the test facility this year using KALIMER-600 as a reference reactor, the basic and the detailed designs will be made through 2011-2012 based on the demonstration reactor which is intended to be constructed by 2028 according to a long-term national SFR development plan. The installation is scheduled to be completed by the end of 2013, and the main experiments will commence from 2015 after the startup test in 2014. This paper briefly introduces the preliminary design features which were produced as a first step to assess the appropriateness of the facility design methodology.

  10. Passive wick fluxmeters: Design considerations and field applications

    Science.gov (United States)

    Gee, G. W.; Newman, B. D.; Green, S. R.; Meissner, R.; Rupp, H.; Zhang, Z. F.; Keller, J. M.; Waugh, W. J.; van der Velde, M.; Salazar, J.

    2009-04-01

    Optimization of water use in agriculture and quantification of percolation from landfills and watersheds require reliable estimates of vadose zone water fluxes. Current technology is limited primarily to lysimeters, which directly measure water flux but are expensive and may in some way disrupt flow, causing errors in the measured drainage. We report on design considerations and field tests of an alternative approach, passive wick fluxmeters, which use a control tube to minimize convergent or divergent flow. Design calculations with a quasi-three-dimensional model illustrate how convergence and divergence can be minimized for a range of soil and climatic conditions under steady state and transient fluxes using control tubes of varying heights. There exists a critical recharge rate for a given wick length, where the fluxmeter collection efficiency is 100% regardless of the height of the control tube. Otherwise, convergent or divergent flow will occur, especially when the control tube height is small. While divergence is eliminated in coarse soils using control tubes, it is reduced but not eliminated in finer soils, particularly for fluxes soils ranging from nonvegetated semiarid settings in the United States to grasslands in Germany and rain-fed crops in New Zealand and the South Pacific. Where side-by-side comparisons of drainage were made between passive wick fluxmeters and conventional lysimeters in the United States and Germany, agreement was very good. In semiarid settings, drainage was found to depend upon precipitation distribution, surface soil, topographic relief, and the type and amount of vegetation. In Washington State, United States, soil texture dominated all factors controlling drainage from test landfill covers. As expected, drainage was greatest (>60% annual precipitation) from gravel surfaces and least (no drainage) from silt loam soils. In Oregon and New Mexico, United States, and in New Zealand, drainage showed substantial spatial variability

  11. 自动上粕机液压系统设计%Design of Hydraulic System for Automatic Loading Machine

    Institute of Scientific and Technical Information of China (English)

    高军霞

    2016-01-01

    An introduction to the main functions and design principle of the hydraulic system for a automatic loading machine was presented.Based on analyzing the action and functions of the hydraulic system of the automatic loading machine, the design scheme of the hydraulic system was put forward and the circuit design process and hydraulic system working principle were introduced in detail.By practical test, the hydraulic system whose performance can meet the demand of automatic loading machine and work stably, has the good market application prospect.%介绍自动上粕机液压系统的主要功能和设计原理。在分析自动上粕机液压系统动作和功能的基础上,提出该液压系统的设计方案,详细阐述了液压系统回路设计过程以及工作原理。经实践测试:该液压系统工作运行平稳,各项性能可满足自动上粕机作业需求,具有良好的市场应用前景。

  12. Hydraulic Fracturing Design of Coal-bed Gas Well%煤层气井水力压裂设计

    Institute of Scientific and Technical Information of China (English)

    张志全; 张军; 许弟龙; 胡东; 张保国; 唐艳

    2001-01-01

    针对煤层气井储层特性和压裂的特殊性,选择了拟三维模型进行水力压裂设计。针对一口具体井的资料进行了模拟计算,计算结果合理。同时就地面注液排量、压裂液稠度系数和地应力差值对裂缝几何形态的影响进行了计算和分析,并提出了相应的建议。%In consideration of reservoir charateristics and particalarity of fracturing of coal-bed gas well,a psuedo 3D fracture model is selected to design the hydraulic fracturing.A simulation calculation is performed with data from a specific well,of which the result is reasonable,at the same time calculation and analysis are conducted on the geometry of fractures based on the displacement of surface injected fluid,density coefficient of fracturing fluid and differential value of earth stress,thus related proposals are made.

  13. The design concept of the 6-degree-of-freedom hydraulic shaker at ESTEC

    Science.gov (United States)

    Brinkman, P. W.; Kretz, D.

    1992-01-01

    The European Space Agency (ESA) has decided to extend its test facilities at the European Space and Technology Center (ESTEC) at Noordwijk, The Netherlands, by implementing a 6-degree-of-freedom hydraulic shaker. This shaker will permit vibration testing of large payloads in the frequency range from 0.1 Hz to 100 Hz. Conventional single axis sine and random vibration modes can be applied without the need for a configuration change of the test set-up for vertical and lateral excitations. Transients occurring during launch and/or landing of space vehicles can be accurately simulated in 6-degrees-of-freedom. The performance requirements of the shaker are outlined and the results of the various trade-offs, which are investigated during the initial phase of the design and engineering program are provided. Finally, the resulting baseline concept and the anticipated implementation plan of the new test facility are presented.

  14. Design, manufacture and evaluation of a hydraulically installed, multi-sampling lysimeter. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Scroppo, J.A.; Scroppo, G.L. [Bladon International, Inc., Oak Brook, IL (United States); Carty, R.H.; Chaimberg, M. [Institute of Gas Technology, Chicago, IL (United States); Timmons, R.D.; O`Donnell, M. [Timco Mfg., Inc., Prairie du Sac, WI (United States)

    1992-06-01

    There is a need for a quick, simple, reliable, and inexpensive on-site method for sampling soil pollutants before they reach the groundwater. Vadose zone monitoring is an important aspect of sound groundwater management. In the vadose zone, where water moves via percolation, this water medium possesses the ability to transfer hazardous wastes to the nation`s groundwater system. Obtaining samples of moisture and contaminants from the vadose zone is necessary if potential problems are to be identified before they reach the water table. Accurate determination of spatial distribution, movement, and concentrations of contaminants is essential to the selection of remediation technologies. There is a need for three-dimentional subsurface characterization technologies to identify the location of hazardous plumes and their migration. Current subsurface characterization methods for dispersed contaminants primarily involve a time consuming, expensive process for drilling wells and taking samples. With no major water flow in the vadose zone, conventional monitoring wells will not function as designed. The multi-sampling lysimeter can be readily linked with physical and chemical sensors for on-site screening. The hydraulically-installed suction lysimeter was capable of extracting soil pore liquid samples from unsaturated test soils without the need to predrill a well. Test results verified that the lysimeters installed with a hydraulic or mechanical ram were able to collect soil pore liquid samples in excess of the amount typically required for monitoring and analysis on a daily basis. Modifications to the prototype design eliminated moving parts and the need for inflatable packers. The elimination of the packer system and the use of porous nickel contributed to increased system ruggedness.

  15. Designing an Electro-Hydraulic Control Module for an Open-Circuit Variable Displacement Pump

    DEFF Research Database (Denmark)

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

    2005-01-01

    , in the form of an electric control signal, under varying working conditions, when having access to engine speed and actual pump pressure. The paper presents a model of both the pump and the control module, along with design considerations on which linear controllers are developed for a worst point...

  16. Design of Hydraulic Pump Detector Based on ARM%基于ARM的液压泵检测仪设计

    Institute of Scientific and Technical Information of China (English)

    高立龙; 王新晴; 蒋文峰; 张红涛

    2013-01-01

    Aim at the conditions that engineering machine has big fluidity, engineering machine hydraulic system is complex and hydraulic pump detection is difficult on the spot. This paper introduces a design of the portable hydraulic pump detector based on ARM embedded system. This detector has S3C6410A based on ARM11 as the core processor, designing signal regulate circuit, photoelectric isolating circuit and friendly data acquisition software, introducing the installation and test methods of hydraulic pump detection, realizing the collection of pump meters and the hydraulic pump performance test on the spot.%针对工程机械流动性大、液压系统复杂、液压泵现场检测困难等情况.该文设计了一种基于ARM嵌入式系统的便携式液压泵检测仪,该检测仪以ARM 11类型处理器S3C6410A为核心,设计了相应的信号整流电路、光电隔离电路和友好的数据采集软件,介绍了液压泵现场检测的安装和检测方法,实现了液压泵参数的现场快速采集和性能曲线的现场绘制.

  17. Hydraulic System Design of Hydraulic-Driven Load Exoskeleton Robot%液压驱动型负重外骨骼机器人液压系统设计

    Institute of Scientific and Technical Information of China (English)

    周加永; 张昂; 莫新民; 赵浩; 纪平鑫

    2016-01-01

    Started from human motion characteristics, the hydraulic drive overall load exoskeleton robot skeleton structure was an-alyzed. According to the characteristics of the load exoskeleton robot, a complete hydraulic drive system was designed, and the main el-ements of the selection calculation were carried out as hydraulic system, hydraulic pumps, servo valves and hydraulic cylinders, and etc. Simhydraulics software was used to establish the simulation schematics for hydraulic system of load exoskeleton robot, study and simulation analysis were carried out for the hydraulic system, and simulation results were proved of the rational design of the hydraulic system. In the last, technology challenges faced by the hydraulic drive load exoskeleton robot are analyzed, which provide reference for further design of the hydraulic system.%从人体运动特征出发,分析了液压驱动负重外骨骼机器人的整体骨架结构。根据负重外骨骼机器人的特点要求设计了一套完整的液压传动系统,对液压系统中液压泵、伺服阀和液压缸等主要元件进行了选型计算。利用Simhydraulics软件建立了负重外骨骼机器人液压系统仿真原理图,并对液压系统进行了仿真分析研究,由仿真结果证明了所设计液压系统的合理性。最后对液压驱动型负重外骨骼机器人技术面临的挑战进行了分析,为该液压系统的深化设计提供了参考。

  18. Feedback Control Systems Loop Shaping Design with Practical Considerations

    Science.gov (United States)

    Kopsakis, George

    2007-01-01

    This paper describes loop shaping control design in feedback control systems, primarily from a practical stand point that considers design specifications. Classical feedback control design theory, for linear systems where the plant transfer function is known, has been around for a long time. But it s still a challenge of how to translate the theory into practical and methodical design techniques that simultaneously satisfy a variety of performance requirements such as transient response, stability, and disturbance attenuation while taking into account the capabilities of the plant and its actuation system. This paper briefly addresses some relevant theory, first in layman s terms, so that it becomes easily understood and then it embarks into a practical and systematic design approach incorporating loop shaping design coupled with lead-lag control compensation design. The emphasis is in generating simple but rather powerful design techniques that will allow even designers with a layman s knowledge in controls to develop effective feedback control designs.

  19. 77 FR 74196 - Draft Guidance for Industry on Safety Considerations for Product Design To Minimize Medication...

    Science.gov (United States)

    2012-12-13

    ... Product Design To Minimize Medication Errors; Availability AGENCY: Food and Drug Administration, HHS... guidance for industry entitled ``Safety Considerations for Product Design to Minimize Medication Errors... using a systems approach to minimize medication errors relating to product design. The draft...

  20. Design of a pictogram of the operator-hydraulic filler system

    Energy Technology Data Exchange (ETDEWEB)

    Bukhgol' ts, V.P.; Dinershtein, V.A.

    1985-09-01

    A modern hydraulic filling system is discussed which consists of two lines: the crusher and sorter preparing the filling material, and the hydraulic filling unit, which includes a mixer and a system of pulp conduits. The process chart of the hydraulic filling system without the crusher-sorter is illustrated. When the system is started, water is first flushed through the pulp conduit, gate valves with drives are opened, and the quantity of water discharged is measured by water output sensors. For effective and failure-free operation of the system, remote control and monitoring elements are introduced into the hydraulic filling system.

  1. Trends in Modelling, Simulation and Design of Water Hydraulic Systems – Motion Control and Open-Ended Solutions

    DEFF Research Database (Denmark)

    Conrad, Finn

    2006-01-01

    The paper presents and discusses a R&D-view on trends in development and best practise in modelling, simulation and design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus...

  2. Factors that affect the hydraulic performance of raingardens: implications for design and maintenance.

    Science.gov (United States)

    Virahsawmy, Harry K; Stewardson, Michael J; Vietz, Geoff; Fletcher, Tim D

    2014-01-01

    Raingardens are becoming an increasingly popular technology for urban stormwater treatment. However, their hydraulic performance is known to reduce due to clogging from deposition of fine-grained sediments on the surface. This impacts on their capacity to treat urban runoff. It has been recently hypothesised that plants can help to mitigate the effect of surface clogging on infiltration. A conceptual model is therefore presented to better understand key processes, including those associated with plant cover, which influences surface infiltration mechanisms. Based on this understanding, a field evaluation was carried out to test the hypothesis that plants increase the infiltration rate, and to investigate factors that influence the deposition of fine-grained sediments within raingardens. The results show that infiltration rates around plants are statistically higher than bare areas, irrespective of the degree of surface clogging. This suggests that preferential flow pathways exist around plants. Sediment deposition processes are also influenced by design elements of raingardens such as the inlet configuration. These findings have implications for the design and maintenance of raingardens, in particular the design of the inlet configuration, as well as maintenance of the filter media surface layer and vegetation.

  3. 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

  4. The design of hydraulic pressure regulators that are stable without the use of sensing line restrictors or frictional dampers

    Science.gov (United States)

    Gold, H.

    1977-01-01

    A direct-acting hydraulic pressure regulator design which incorporates stability margin, response and droop margin is developed. The pressure regulator system does not involve a nonlinear sensing line restrictor (which may degrade transient response) or linear damping (which is sensitive to clearance and viscosity). The direct-acting hydraulic pressure regulator makes use of the technique of lead network stabilization (i.e., the tuned stabilizer concept). An analytically derived circuit pressure regulator is tested to study the stability limit under a parallel capacitive plus resistive load and the stabilizing effect of the tuned stabilizer.

  5. IT-Tools Concept for Simulation and Design of Water Hydraulic Mechatronic Test Facilities for Motion Control and Operation in Environmentally Sensitive Application Areas

    DEFF Research Database (Denmark)

    Conrad, Finn; Pobedza, J.; Sobczyk, A.

    2004-01-01

    This paper presents a proposed IT-Tools concept for modeling, simulation, analysis and design of water hydraulic actuators for motion control of machines, lifts, cranes and robots. The designed test rigs have tap water hydraulic components of the Danfoss Nessie® product family and equipped...

  6. Design considerations for lunar base photovoltaic power systems

    Science.gov (United States)

    Hickman, J. Mark; Curtis, Henry B.; Landis, Geoffrey A.

    1990-01-01

    A survey was made of factors that may affect the design of photovoltaic arrays for a lunar base. These factors, which include the lunar environment and system design criteria, are examined. A photovoltaic power system design with a triangular array geometry is discussed and compared to a nuclear reactor power systems and a power system utilizing both nuclear and solar power sources.

  7. Design considerations for HFQ® hot stamped aluminium structural panels

    Directory of Open Access Journals (Sweden)

    Foster Alistair

    2015-01-01

    Full Text Available HFQ is a deep drawing process for alloyed aluminium sheet that can be used to produce complex-stamped forms while maintaining the high-strength of 6xxx and 7xxx alloys. By adopting a strategy to design for HFQ at the platform level, designers can reduce part count (thereby reducing cost and weight, reduce gauge (thereby reducing weight, and improve part packaging. Two simple design examples are given to assist designers in evolving traditionally formed panel designs to HFQ formed solutions. Example features are used to illustrate the effect of geometry, thickness and strength on the final structural component.

  8. 基于有限元分析的2MN四柱液压机液压缸设计%Design of Hydraulic Cylinder for 2 MN Four-column Hydraulic Press Based on FEM Analysis

    Institute of Scientific and Technical Information of China (English)

    卜匀; 王会刚; 刘晓雯

    2014-01-01

    The hydraulic cylinder is a widely used actuators.Based on the design theory for hydraulic press,the structure design method of four-column hydraulic press hydraulic cylinder was introduced.Static finite element analysis of cylinder part was done.Then optimization scheme was proposed.The finite element analysis results show that the improvement design is reasonable.%液压缸是一种应用广泛的执行元件。依据液压机设计理论,介绍四柱式液压机液压缸结构设计方法,对缸筒部件进行静态有限元分析,提出优化改进方案,有限元分析结果表明改进设计合理。

  9. 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

  10. Capture-zone design in an aquifer influenced by cyclic fluctuations in hydraulic gradients

    Science.gov (United States)

    Zawadzki, Willy; Chorley, Don; Patrick, Guy

    2002-10-01

    Design of a groundwater pumping and treatment system for a wood-treatment facility adjacent to the tidally influenced Fraser River estuary required the development of methodologies to account for cyclic variations in hydraulic gradients. Design of such systems must consider the effects of these cyclic fluctuations on the capture of dissolved-phase contaminants. When the period of the cyclic fluctuation is much less than the travel time of the dissolved contaminant from the source to the discharge point, the hydraulic-gradient variations resulting from these cycles can be ignored. Capture zones are then designed based on the average hydraulic gradient determined using filter techniques on continuous groundwater-level measurements. When the period of cyclic fluctuation in hydraulic gradient is near to or greater than the contaminant travel time, the resulting hydraulic-gradient variations cannot be ignored. In these instances, procedures are developed to account for these fluctuations in the capture-zone design. These include proper characterization of the groundwater regime, assessment of the average travel time and period of the cyclic fluctuations, and numerical techniques which allow accounting for the cyclic fluctuations in the design of the capture zone. Résumé. L'étude d'un système de pompage et de traitement de l'eau souterraine d'une usine de traitement du bois proche de l'estuaire de la rivière Fraser, influencé par les marées, a nécessité la mise au point de méthodologies pour prendre en compte les variations cycliques de gradients hydrauliques. L'étude de tels systèmes doit considérer les effets de ces variations cycliques sur l'extraction des contaminants en phase dissoute. Lorsque la période des variations cycliques est très inférieure au temps de parcours du contaminant dissous entre la source et le point d'émergence, les variations du gradient hydraulique résultant de ces cycles peuvent être ignorées. Les zones d'extraction sont

  11. Design of a New Energy-saving Hydraulic Cylinder%一种新型节能液压缸的设计

    Institute of Scientific and Technical Information of China (English)

    田灵飞; 陈龙淼

    2011-01-01

    In order to improve the efficiency of hydraulic cylinder, on the basis of improving hydraulic cylinder structure and hydraulic circuit design, a new energy-saving hydraulic cylinders was designed which was a combination of piston-cylinder and plungercylinder.The hydraulic cylinder has the characteristics of saving energy and improving the efficiency of hydraulic system.%为提高液压缸的工作效率,从改进液压缸结构以及液压回路的设计出发,设计一种基于柱塞缸与活塞缸的组合式新型节能高效液压缸.使用该液压缸既能节约液压能,又能提高液压系统效率.

  12. A methodology for integrating sustainability considerations into process design

    OpenAIRE

    Azapagic, A.; Millington, A.; Collett, A

    2006-01-01

    Designing more sustainable processes is one of the key challenges for sustainable development of the chemical industry. This is by no means a trivial task as it requires translating the theoretical principles of sustainable development into design practice. At present, there is no general methodology to guide sustainable process design and almost no practical experience. In an attempt to contribute to this emerging area, this paper proposes a new methodology for integrating sustainability con...

  13. Design considerations for beamwaveguide in the NASA Deep Space Network

    Science.gov (United States)

    Veruttipong, Thavath; Withington, James R.; Galindo-Israel, Victor; Imbraile, William A.; Bathker, Dan A.

    1988-01-01

    A generalized solution is found for retrofitting a large dual-shaped reflector antenna for a beamwaveguide. The design is termed as a bypass beamwaveguide. Both highpass design feed imaging and bandpass design feed imaging are considered. Each design was studied using geometrical optics, Gaussian wave analysis, and both low-frequency and high-frequency diffraction analysis. An important extension of the Mizusawa-Kitsuregawa criteria was discovered (Zusama and Kitsuregawa, 1973). The principle revealed shows how a two-reflector cell, although in itself distorting, may be combined with a second cell which compensates for the first and delivers an output beam which is a good image of the input beam.

  14. Design software for hydraulic circuits [for heating systems]; Ontwerpsoftware voor hydraulische schakelingen

    Energy Technology Data Exchange (ETDEWEB)

    Soethout, L.L. [Afdeling Gezonde Gebouwen en Installaties, TNO Bouw, Delft (Netherlands); Aerts, J. [ISSO, Rotterdam (Netherlands); Plokker, W. [Vabi, Delft (Netherlands)

    2006-02-15

    A method for designing hydraulic circuits for heating applications is described, based on the 1998 ISSO Publication 44. Also attention is paid to the development of software to support this method. The aim of the method is to achieve a design that works well both at full load and at partial load. The main approach is to assemble the water side of the installation from modules that are mutually independent as far as possible. These models are selected from a library of standard modules for emission, generation and distribution. The user is given support in choosing the correct module according to the heat requirement of the building and zones within it, and in configuring the modules to obtain efficient operation at full load and controllability at part load. [Dutch] Een methode voor het ontwerp van hydraulische schakelingen voor verwarming wordt beschreven, gebaseerd op de in 1998 gepubliceerde ISSO-publicatie 44, Tevens wordt aandacht gegeven aan de ontwikkeling van software ter ondersteuning van de methode. De methode beoogt tot een ontwerp te leiden dat zowel bij vollast als bij deellast goed werkt. Uitgangspunt is de opbouw van de waterzijdige installatie met modulen die elkaar zo min mogelijk beinvloeden. Deze modulen worden gekozen uit een bibliotheek van standaard modulen voor afgifte, opwekking en distributie. De gebruiker krijgt ondersteuning om, afhankelijk van de warmtebehoefte van het gebouw en zones hierin, de juiste modulen te selecteren, en deze te configureren voor een goede werking bij vollast en een goede regeling bij deellast.

  15. Biomechanical design considerations for transradial prosthetic interface: A review.

    Science.gov (United States)

    Sang, Yuanjun; Li, Xiang; Luo, Yun

    2016-03-01

    Traditional function and comfort assessment of transradial prostheses pay scant attention to prosthetic interface. With better understanding of the biomechanics of prosthetic interface comes better efficiency and safety for interface design; in this way, amputees are more likely to accept prosthetic usage. This review attempts to provide design and selection criteria of transradial interface for prosthetists and clinicians. Various transradial socket types in the literature were chronologically reviewed. Biomechanical discussion of transradial prosthetic interface design from an engineering point of view was also done. Suspension control, range of motion, stability, as well as comfort and safety of socket designs have been considered in varying degrees in the literature. The human-machine interface design should change from traditional "socket design" to new "interface design." From anatomy and physiology to biomechanics of the transradial residual limb, the force and motion transfer, together with comfort and safety, are the two main aspects in prosthetic interface design. Load distribution and transmission should mainly rely on achieving additional skeletal control through targeted soft tissue relief. Biomechanics of the residual limb soft tissues should be studied to find the relationship between mechanical properties and the comfort and safety of soft tissues. © IMechE 2016.

  16. Feed-in Tariffs: Good Practices and Design Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Sadie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Esterly, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-01-02

    In recent years, feed-in tariff (FIT) activity has focused primarily on revisions to current policies, underscoring the need for stable and predictable, yet flexible, policy environments. This policy brief provides a primer on key FIT design elements, lessons from country experience, and support resources to enable more detailed and country-specific FIT policy design.

  17. Renewable Electricity Standards: Good Practices and Design Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Sadie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Esterly, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-01-02

    In widespread use globally, renewable electricity standards (RES) are one of the most widely adopted renewable energy policies and a critical regulatory vehicle to accelerate renewable energy deployment. This policy brief provides an introduction to key RES design elements, lessons from country experience, and support resources to enable more detailed and country-specific RES policy design.

  18. Design and control considerations for industrial and space manipulators

    Science.gov (United States)

    Whitney, D. E.; Book, W. J.; Lynch, P. M.

    1974-01-01

    This paper is a progress report summarizing theoretical and practical results concerning integration of design and control aspects of manipulator arms for industrial or space applications. The relationships between task specifications, gross motions, fine motions, actuator type and location, size and strength of structural members, control servos and strategies, and overall design evaluation are briefly discussed, with some technical examples.

  19. Design Considerations of Permanent Magnet Transverse Flux Machines

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Rasmussen, Peter Omand; Ritchie, Ewen

    2011-01-01

    Permanent magnet transverse flux machine (PMTFM) is well known for its high torque density and is interested in various direct-drive applications. Due to its complicated 3-D flux components, design and design optimization of a PMTFM is more difficult and time consuming than for radial flux...

  20. Design and control considerations for industrial and space manipulators

    Science.gov (United States)

    Whitney, D. E.; Book, W. J.; Lynch, P. M.

    1974-01-01

    This paper is a progress report summarizing theoretical and practical results concerning integration of design and control aspects of manipulator arms for industrial or space applications. The relationships between task specifications, gross motions, fine motions, actuator type and location, size and strength of structural members, control servos and strategies, and overall design evaluation are briefly discussed, with some technical examples.

  1. Design considerations for an archimedean slot spiral antenna

    Science.gov (United States)

    Nurnberger, Michael W.; Volakis, John L.

    1995-01-01

    The design goal is to develop a 118-157 MHz, vertically polarized, low-profile (or conformal) antenna as a replacement for VHF AM blade antennas on aircraft. This design is to be arrived at by scaling the dimensions of an antenna designed for a center frequency of 1.1 GHz. The design prior to scaling may have the following maximum dimensions: diameter less than 3.70 in. and thickness less than 0.50 in. Although a four-arm spiral design was originally suggested, a two-arm spiral may also be used, as both mode-1 and mode-2 (sum and difference) radiation patterns aren't required. While a four-arm spiral can easily be designed should both sum and difference patterns be required, the two-arm design will provide the required sum pattern and simplify the design problem somewhat: only one feed is required, and the feed area geometry is more straightforward. Polarization requirements dictate that a slot spiral be used, as opposed to a wire spiral. Two similar radiating structures were considered. The first is the standard archimedean spiral antenna. The second is a hollow archimedean spiral antenna, essentially a standard archimedean spiral with the inner portion removed.

  2. Improve Designing for Heavy-duty Automobile Hydraulic Tank%某重型汽车液压油箱的改进设计

    Institute of Scientific and Technical Information of China (English)

    高军

    2012-01-01

    本文分析了某重型汽车车载液压动力系统失效的原因,介绍了液压油箱设计原则,并对液压油箱进行了改进设计。%this article analyzed the failing reason of heavy-duty automobile hydraulic system, and introduced designing principle of hydraulic tank, also redesigned the hydraulic tank.

  3. Numerical design and optimization of hydraulic resistance and wall shear stress inside pressure-driven microfluidic networks.

    Science.gov (United States)

    Damiri, Hazem Salim; Bardaweel, Hamzeh Khalid

    2015-11-07

    Microfluidic networks represent the milestone of microfluidic devices. Recent advancements in microfluidic technologies mandate complex designs where both hydraulic resistance and pressure drop across the microfluidic network are minimized, while wall shear stress is precisely mapped throughout the network. In this work, a combination of theoretical and modeling techniques is used to construct a microfluidic network that operates under minimum hydraulic resistance and minimum pressure drop while constraining wall shear stress throughout the network. The results show that in order to minimize the hydraulic resistance and pressure drop throughout the network while maintaining constant wall shear stress throughout the network, geometric and shape conditions related to the compactness and aspect ratio of the parent and daughter branches must be followed. Also, results suggest that while a "local" minimum hydraulic resistance can be achieved for a geometry with an arbitrary aspect ratio, a "global" minimum hydraulic resistance occurs only when the aspect ratio of that geometry is set to unity. Thus, it is concluded that square and equilateral triangular cross-sectional area microfluidic networks have the least resistance compared to all rectangular and isosceles triangular cross-sectional microfluidic networks, respectively. Precise control over wall shear stress through the bifurcations of the microfluidic network is demonstrated in this work. Three multi-generation microfluidic network designs are considered. In these three designs, wall shear stress in the microfluidic network is successfully kept constant, increased in the daughter-branch direction, or decreased in the daughter-branch direction, respectively. For the multi-generation microfluidic network with constant wall shear stress, the design guidelines presented in this work result in identical profiles of wall shear stresses not only within a single generation but also through all the generations of the

  4. Design considerations in Li/SOCl{sub 2} battery technology

    Energy Technology Data Exchange (ETDEWEB)

    Cieslak, W.R.

    1994-02-01

    Li/SOCl{sub 2} battery technology is attractive by virtue of its high energy density, low self-discharge rate, and ability to to perform well at a wide variety of discharge rates. However, some of these same attributes also make Li/SOCl{sub 2} cells capable of hightly exothermic events when handled under abnormal conditions. We manage the energy safely and optimize the performance by tailoring the design to the application. We have developed three different ``D`` size cells that target low, moderate, and high rate applications. Each design provides safe and efficient performance, although, in progressing from low to high rate capability, the likelihood of venting under abuse conditions increses. We incorporate a vent mechanism in all designs as the ultimate protection from severe abuse. The details of our battery designs and the benefits of application-specific design are discussed.

  5. Effect of the method of estimation of soil saturated hydraulic conductivity with regards to the design of stormwater infiltration trenches

    Science.gov (United States)

    Paiva coutinho, Artur; Predelus, Dieuseul; Lassabatere, Laurent; Ben Slimene, Erij; Celso Dantas Antonino, Antonio; Winiarski, Thierry; Joaquim da Silva Pereira Cabral, Jaime; Angulo-Jaramillo, Rafael

    2014-05-01

    Best management practices are based on the infiltration of stormwater (e.g. infiltration into basins or trenches) to reduce the risk of flooding of urban areas. Proper estimations of saturated hydraulic conductivity of the vadose zone are required to avoid inappropriate design of infiltration devices. This article aims at assessing (i) the method-dependency of the estimation of soils saturated hydraulic conductivity and (ii) the consequences of such dependency on the design of infiltration trenches. This is illustrated for the specific case of an infiltration trench to be constructed to receive stormwater from a specific parking surface, 250 m2 in area, in Recife (Brazil). Water infiltration experiments were conducted according to the Beerkan Method, i.e. application of a zero water pressure head through a disc source (D=15 cm) and measures of the amount of infiltrated water with time. Saturated hydraulic conductivity estimates are derived from the analysis of these infiltration tests using several different conceptual approaches: one-dimensional models of Horton(1933) and Philip(1957), three-dimensional methods recently developed (Lassabatere et al., 2006, Wu et al., 1999, and Bagarello et al., 2013) and direct 3-dimensional numerical inversion. The estimations for saturated hydraulic conductivity ranged between 65.5 mm/h and 94 mm/h for one-dimensional methods, whereas using three-dimensional methods saturated hydraulic conductivity ranged between 15.6 mm/h and 50 mm/h. These results shows the need for accounting for 3D geometry, and more generally, the physics of water infiltration in soils, if a proper characterization of soil saturated hydraulic conductivity is targeted. In a second step, each estimate of the saturated hydraulic conductivity was used to calculate the stormwater to be stored in the studied trench for several rainfall events of recurrence intervals of 2 to 25 years. The calculation of these volumes showed a great sensitivity with regards to the

  6. Manual for the thermal and hydraulic design of direct contact spray columns for use in extracting heat from geothermal brines

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, H.R.

    1985-06-01

    This report outlines the current methods being used in the thermal and hydraulic design of spray column type, direct contact heat exchangers. It provides appropriate referenced equations for both preliminary design and detailed performance. The design methods are primarily empirical and are applicable for us in the design of such units for geothermal application and for application with solar ponds. Methods for design, for both preheater and boiler sections of the primary heat exchangers, for direct contact binary powers plants are included. 23 refs., 8 figs.

  7. On-chip antenna: Practical design and characterization considerations

    KAUST Repository

    Shamim, Atif

    2012-07-28

    This paper highlights the challenges of an emergent field, namely, on-chip antenna design. Consistent with the RF System-on-Chip (SoC) concept, co-design strategy for circuits and on-chip antennas is described. A number of design and layout issues, arising from the highly integrated nature of this kind of systems, are discussed. The characterization difficulties related to on-chip antennas radiation properties are also highlighted. Finally, a novel on-wafer test fixture is proposed to measure the gain and radiation pattern of the on-chip antennas in the anechoic chamber.

  8. Design Considerations of a Solid State Thermal Energy Storage

    Science.gov (United States)

    Janbozorgi, Mohammad; Houssainy, Sammy; Thacker, Ariana; Ip, Peggy; Ismail, Walid; Kavehpour, Pirouz

    2016-11-01

    With the growing governmental restrictions on carbon emission, renewable energies are becoming more prevalent. A reliable use of a renewable source however requires a built-in storage to overcome the inherent intermittent nature of the available energy. Thermal design of a solid state energy storage has been investigated for optimal performance. The impact of flow regime, laminar vs. turbulent, on the design and sizing of the system is also studied. The implications of low thermal conductivity of the storage material are discussed and a design that maximizes the round trip efficiency is presented. This study was supported by Award No. EPC-14-027 Granted by California Energy Commission (CEC).

  9. Practical considerations for adaptive trial design and implementation

    CERN Document Server

    Pinheiro, José; Kuznetsova, Olga

    2014-01-01

    This edited volume is a definitive text on adaptive clinical trial designs from creation and customization to utilization. As this book covers the full spectrum of topics involved in the adaptive designs arena, it will serve as a valuable reference for researchers working in industry, government and academia. The target audience is anyone involved in the planning and execution of clinical trials, in particular, statisticians, clinicians, pharmacometricians, clinical operation specialists, drug supply managers, and infrastructure providers.  In spite of the increased efficiency of adaptive trials in saving costs and time, ultimately getting drugs to patients sooner, their adoption in clinical development is still relatively low.  One of the chief reasons is the higher complexity of adaptive design trials as compared to traditional trials. Barriers to the use of clinical trials with adaptive features include the concerns about the integrity of study design and conduct, the risk of regulatory non-acceptance, t...

  10. Geothermal FIT Design: International Experience and U.S. Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Rickerson, W.; Gifford, J.; Grace, R.; Cory, K.

    2012-08-01

    Developing power plants is a risky endeavor, whether conventional or renewable generation. Feed-in tariff (FIT) policies can be designed to address some of these risks, and their design can be tailored to geothermal electric plant development. Geothermal projects face risks similar to other generation project development, including finding buyers for power, ensuring adequate transmission capacity, competing to supply electricity and/or renewable energy certificates (RECs), securing reliable revenue streams, navigating the legal issues related to project development, and reacting to changes in existing regulations or incentives. Although FITs have not been created specifically for geothermal in the United States to date, a variety of FIT design options could reduce geothermal power plant development risks and are explored. This analysis focuses on the design of FIT incentive policies for geothermal electric projects and how FITs can be used to reduce risks (excluding drilling unproductive exploratory wells).

  11. Multiaxial and thermomechanical fatigue considerations in damage tolerant design

    Science.gov (United States)

    Leese, G. E.; Bill, R. C.

    1985-01-01

    In considering damage tolerant design concepts for gas turbine hot section components, several challenging concerns arise: Complex multiaxial loading situations are encountered; Thermomechanical fatigue loading involving very wide temperature ranges is imposed on components; Some hot section materials are extremely anisotropic; and coatings and environmental interactions play an important role in crack propagation. The effects of multiaxiality and thermomechanical fatigue are considered from the standpoint of their impact on damage tolerant design concepts. Recently obtained research results as well as results from the open literature are examined and their implications for damage tolerant design are discussed. Three important needs required to advance analytical capabilities in support of damage tolerant design become readily apparent: (1) a theoretical basis to account for the effect of nonproportional loading (mechanical and mechanical/thermal); (2) the development of practical crack growth parameters that are applicable to thermomechanical fatigue situations; and (3) the development of crack growth models that address multiple crack failures.

  12. Ultra-mobile rugged computing platform design considerations

    Science.gov (United States)

    Garcia, Ray; Wright-Johnson, Mark; Daniels, Reginald

    2011-06-01

    State of the art mobile computing is designed to withstand variable rugged environments. Specific platforms including mobile phones, GPS devices, tablets, Netbooks and laptops that are used by the general public and increasingly by dismounted military users.

  13. Propagation considerations in the American Mobile Satellite system design

    Science.gov (United States)

    Kittiver, Charles; Sigler, Charles E., Jr.

    1993-01-01

    An overview of the American Mobile Satellite Corporation (AMSC) mobile satellite services (MSS) system with special emphasis given to the propagation issues that were considered in the design is presented. The aspects of the voice codec design that effect system performance in a shadowed environment are discussed. The strategies for overcoming Ku-Band rain fades in the uplink and downlink paths of the gateway station are presented. A land mobile propagation study that has both measurement and simulation activities is described.

  14. Optimum municipal wastewater treatment plant design with consideration of uncertainty

    Institute of Scientific and Technical Information of China (English)

    ZENG Guang-ming; LIN Yu-peng; QIN Xiao-sheng; HUANG Guo-he; LI Jian-bing; JIANG Ru

    2004-01-01

    A newly developed model for the optimum municipal wastewater treatment plant (MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by the fluctuation of the wastewater quality and quantity during the design of MWTP. The model solution procedure is illustrated in detail, and a numerical example is given to verify the feasibility and advantage of the model. Furthermore, the possibility of the model application is briefly outlined.

  15. DESIGN CONSIDERATIONS FOR SERIES HYBRID ACTIVE POWER FILTER

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Some important factors for designing a series hybrid active power filter (SHAPF) are presented in this paper for the case when the load is varied in a wide range and/or the source voltage is seriously distorted. Special design of passive filters, adaptive control of parameter and multi variant control are discussed in detail. The filter is stable, has good performance, and causes small capacitive reactive current. The simulation and experimental results accorded with the theoretical analysis results.

  16. Design Considerations for an Underactuated Robotic Finger Mechanism

    Institute of Scientific and Technical Information of China (English)

    YAO Shuangji; CECCARELLI Marco; ZHAN Qiang; ARBONE Giuseppe; LU Zhen

    2009-01-01

    A design approach is presented in this paper for underactuation in robotic finger mechanisms. The characters of underactuated finger mechanisms are introduced as based on linkage and spring systems. The feature of self-adaptive enveloping grasp by underactuated finger mechanisms is discussed with feasible in grasping unknown objects. The design problem of robotic fingers is analyzed by looking at many aspects for an optimal functionality. Design problems and requirements for underactuated mechanisms are formulated as related to human-like robotic fingers. In particular, characteristics of finger mechanisms are analyzed and optimality criteria are summarized with the aim to formulate a general design algorithm. A general multi-objective optimization design approach is applied as based on a suitable optimization problem by using suitable expressions of optimality criteria. An example is illustrated as an improvement of finger mechanism in Laboratory of Robotics and Mechatronics (LARM) Hand. Results of design outputs and grasp simulations are reported with the aim to show the practical feasibility of the proposed concepts and computations.

  17. Initial MPTS study results: Design considerations and issues

    Science.gov (United States)

    Maynard, O. E.

    1980-01-01

    One of the key issues identified during investigations of microwave power transmission systems from 1965 to 1976 was the need to assure that the billions of diodes on ground-based rectennas are sufficiently reliable to support long life times of approximately 30 years. Major systems studies conducted focused on waveguides; radio frequency interference and biological considerations; the relationship between performance, weight, and cost; risk assessment; crossed field directional amplifier noise; a 48 kW klystron; effects of the environment on propagation and phase control; rectenna technology; a rationale for the ground power density region; alternate technologies for orbital assembly; ionospheric effects and phase control; and reception conversion (rf to dc collector/converter).

  18. System design considerations for fast-neutron interrogation systems

    Energy Technology Data Exchange (ETDEWEB)

    Micklich, B.J.; Curry, B.P.; Fink, C.L.; Smith, D.L.; Yule, T.J.

    1993-10-01

    Nonintrusive interrogation techniques that employ fast neutrons are of interest because of their sensitivity to light elements such as carbon, nitrogen, and oxygen. The primary requirement of a fast-neutron inspection system is to determine the value of atomic densities, or their ratios, over a volumetric grid superimposed on the object being interrogated. There are a wide variety of fast-neutron techniques that can provide this information. The differences between the various nuclear systems can be considered in light of the trade-offs relative to the performance requirements for each system`s components. Given a set of performance criteria, the operational requirements of the proposed nuclear systems may also differ. For instance, resolution standards will drive scanning times and tomographic requirements, both of which vary for the different approaches. We are modelling a number of the fast-neutron interrogation techniques currently under consideration, to include Fast Neutron Transmission Spectroscopy (FNTS), Pulsed Fast Neutron Analysis (PFNA), and its variant, 14-MeV Associated Particle Imaging (API). The goals of this effort are to determine the component requirements for each technique, identify trade-offs that system performance standards impose upon those component requirements, and assess the relative advantages and disadvantages of the different approaches. In determining the component requirements, we will consider how they are driven by system performance standards, such as image resolution, scanning time, and statistical uncertainty. In considering the trade-offs between system components, we concentrate primarily on those which are common to all approaches, for example: source characteristics versus detector array requirements. We will then use the analysis to propose some figures-of-merit that enable performance comparisons between the various fast-neutron systems under consideration. The status of this ongoing effort is presented.

  19. Thermal Hydraulic Design and Analysis of a Water-Cooled Ceramic Breeder Blanket with Superheated Steam for CFETR

    Science.gov (United States)

    Cheng, Xiaoman; Ma, Xuebin; Jiang, Kecheng; Chen, Lei; Huang, Kai; Liu, Songlin

    2015-09-01

    The water-cooled ceramic breeder blanket (WCCB) is one of the blanket candidates for China fusion engineering test reactor (CFETR). In order to improve power generation efficiency and tritium breeding ratio, WCCB with superheated steam is under development. The thermal-hydraulic design is the key to achieve the purpose of safe heat removal and efficient power generation under normal and partial loading operation conditions. In this paper, the coolant flow scheme was designed and one self-developed analytical program was developed, based on a theoretical heat transfer model and empirical correlations. Employing this program, the design and analysis of related thermal-hydraulic parameters were performed under different fusion power conditions. The results indicated that the superheated steam water-cooled blanket is feasible. supported by the National Special Project for Magnetic Confined Nuclear Fusion Energy of China (Nos. 2013GB108004, 2014GB122000 and 2014GB119000), and National Natural Science Foundation of China (No. 11175207)

  20. Some design considerations for ceramic components in heat engine applications

    Science.gov (United States)

    Gyekenyesi, John P.

    1986-01-01

    The design methodology for brittle material structures which is being developed and used at the Lewis Research Center for sizing ceramic components in heat engine applications is reviewed. Theoretical aspects of designing with structural ceramics are discussed, and a general purpose reliability program for predicting fast fracture response due to volume distributed flaws is described. Statistical treatment of brittle behavior, based on the Weibull model, is reviewed and its advantages, as well as drawbacks, are listed. A mechanistic statistical fracture theory, proposed by Batdorf to overcome the Weibull model limitations and based on Griffith fracture mechanics, is summarized. Failure probability predictions are made for rotating annular Si3N4 disks using various fracture models, and the results are compared to actual failure data. The application of these design methods to Government funded ceramics engine demonstration programs is surveyed. The uncertainty in observed component performance emphasizes the need for proof testing and improved nondestructive evaluation to guarantee adequate structural integrity.

  1. Mechanical design and thermo-hydraulic simulation of the infrared thermography diagnostic of the WEST tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Micolon, Frédéric, E-mail: frederic.micolon@cea.fr; Courtois, Xavier; Aumeunier, Marie-Hélène; Chenevois, Jean-Pierre; Larroque, Sébastien

    2015-10-15

    The WEST (Tungsten (W) Environment in Steady state Tokamak) project is a partial rebuild of the Tore Supra tokamak to make it an X-point metallic environment machine aimed at testing ITER technologies in relevant plasma environment. For the safe operation of the WEST tokamak, infra-red (IR) thermography is a crucial diagnostic as it is a sound and reliable way to detect hotspots or abnormal heating patterns on the plasma facing components (PFCs). Thus WEST will be fitted with middle/short-IR (1.5–2 μm or 3–5 μm) cameras in the upper port plugs to get a full view of the critical PFCs (in particular the new lower divertor) and radio-frequency (RF) heating antennas and one camera at the equatorial level to monitor the new upper divertor and the first wall. This paper describes the design of the up-to-date optical system along with the hydraulic analysis and the thermal and mechanical finite element analysis conducted to ensure adequate heat extraction capabilities. Boundary conditions and simulation results will be presented and discussed as well as technological solutions retained.

  2. Designing terraces for the rainfed farming region in Iraq using the RUSLE and hydraulic principles

    Directory of Open Access Journals (Sweden)

    Mohammad H. Hussein

    2016-03-01

    Full Text Available The rainfed region in Iraq comprises an area of more than 5 million ha of forest, grazing and farmland areas. Except the plains, the region suffers from moderate to severe water erosion due mainly to overgrazing and land mismanagement. Due to population growth and the shortage in water resources, an expansion in land used for agriculture in the region is expected. Terracing is an option when utilizing sloping land for agricultural production. A terrace design criterion was developed for the region in which terrace spacing was determined using the Revised Universal Soil Loss Equation (RUSLE; terrace channel specifications were determined using conventional hydraulic computations. Analyses showed that terracing is feasible on rolling and hilly sloping land in the high rainfall zone (seasonal rainfall >600 mm where economic crops are grown to offset the high cost of terrace construction and maintenance. In the medium and low rainfall zones (seasonal rainfall 400–600 mm and 300–400 mm, terracing for water erosion control is generally not needed on cultivated land less than 10% in slope where wheat and barley crops are normally grown; however, pioneer research projects are needed to assess the feasibility of terraces of the level (detention type to conserve rain water in these two zones for a more successful rainfed farming venture.

  3. Hydraulic performance of biofilter systems for stormwater management: Influences of design and operation

    Science.gov (United States)

    Le Coustumer, Sébastien; Fletcher, Tim D.; Deletic, Ana; Barraud, Sylvie; Lewis, Justin F.

    2009-09-01

    SummaryIn order to evaluate the long-term performance of stormwater biofilters, a study was undertaken to assess their hydraulic conductivity. Despite variability in conductivity (40% being below the recommended range of 50-200 mm/h, 43% within it, and 17% above), treatment performance is unlikely to be affected, as most systems are over-sized such that their detention storage volume compensates for reduced media conductivity. The study broadly reveals two types of systems: some with a high initial conductivity (>200 mm/h) and some with a low initial value (biofilters in the former group, although most are shown to maintain an acceptably high conductivity. Those with initially low conductivity do not change greatly over time. Site characteristics such as filter area (relative to catchment area), age and inflow volume were not useful predictors of conductivity, with initial conductivity of the original media being the most powerful explanatory variable. It is clear therefore, that strict attention must be paid to the specification of original filter media, to ensure that it satisfies design requirements.

  4. Design of a hydraulic analog of the circulatory system for evaluating artificial hearts.

    Science.gov (United States)

    Donovan, F M

    1975-01-01

    A major problem in improving artificial heart designs is the absence of methods for accurate in vitro testing of artificial heart systems. A mock circulatory system has been constructed which hydraulically simulates the systemic and pulmonary circulations of the normal human. The device is constructed of 1/2 in. acrylic sheet and has overall dimensions of 24 in. wide, 16 in. tall, and 8 in. deep. The artificial heart to be tested is attached to the front of the device, and pumps fluid from the systemic venous chamber into the pulmonary arterial chamber and from the pulmonary venous chamber into the systemic arterial chamber. Each of the four chambers is hermetically sealed. The compliance of each chamber is determined by the volume of air trapped above the fluid in that chamber. The pulmonary and systemic resistances are set automatically by bellows-operated valves to simulate the barroreceptor response in the systemic arteries and the passive pulmonary resistance response in the pulmonary arteries. Cardiac output is measured by a turbine flowmeter in the systemic circulation. Results using the Kwan-Gett artificial heart show a good comparison between the mock circulatory system response and the calf response.

  5. Magnet Design Considerations for Fusion Nuclear Science Facility

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Y. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Kessel, C. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); El-Guebaly, L. [Univ. of Wisconsin, Madison, WI (United States) Fusion Technology Institute; Titus, P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

    2016-06-01

    The Fusion Nuclear Science Facility (FNSF) is a nuclear confinement facility that provides a fusion environment with components of the reactor integrated together to bridge the technical gaps of burning plasma and nuclear science between the International Thermonuclear Experimental Reactor (ITER) and the demonstration power plant (DEMO). Compared with ITER, the FNSF is smaller in size but generates much higher magnetic field, i.e., 30 times higher neutron fluence with three orders of magnitude longer plasma operation at higher operating temperatures for structures surrounding the plasma. Input parameters to the magnet design from system code analysis include magnetic field of 7.5 T at the plasma center with a plasma major radius of 4.8 m and a minor radius of 1.2 m and a peak field of 15.5 T on the toroidal field (TF) coils for the FNSF. Both low-temperature superconductors (LTS) and high-temperature superconductors (HTS) are considered for the FNSF magnet design based on the state-of-the-art fusion magnet technology. The higher magnetic field can be achieved by using the high-performance ternary restacked-rod process Nb3Sn strands for TF magnets. The circular cable-in-conduit conductor (CICC) design similar to ITER magnets and a high-aspect-ratio rectangular CICC design are evaluated for FNSF magnets, but low-activation-jacket materials may need to be selected. The conductor design concept and TF coil winding pack composition and dimension based on the horizontal maintenance schemes are discussed. Neutron radiation limits for the LTS and HTS superconductors and electrical insulation materials are also reviewed based on the available materials previously tested. The material radiation limits for FNSF magnets are defined as part of the conceptual design studies for FNSF magnets.

  6. Considerations on Seismic Design of Installations using Natural Gas Fuel

    Directory of Open Access Journals (Sweden)

    Adriana Tokar

    2016-10-01

    Full Text Available The paper presents issues relating to existing standards underlying seismic design restrictions for non-structural components (NSC related to constructions. Are presented measures that can be implemented to maintain a high level of safety in case of earthquake, natural gas plants, which due to the flammability of fuel, carry some risk of fire or explosion. The purpose of this paper is to highlight the need for seismic design of facilities using natural gas fuel for new buildings but also to review the existing installations in buildings by taking mandatory measures.

  7. Mems Electromagnetic Micro Relays Overview and Design Considerations

    Directory of Open Access Journals (Sweden)

    Zuraini Dahari, Thurai Vinay and Dinesh Sood

    2012-10-01

    Full Text Available Miniature electromagnetic relay matrices capable of switching currents up to one ampere range are  widely used in commercial applications such as instrumentation and telecommunication. Traditionally these devices have been fabricated from a number of discrete components, however in recent years the emergence of Micro Electro Mechanical System (MEMS technology has opened up the possibility for batch fabrication of microrelays at much reduced unit cost. While several electromagnetic microrelay designs have been successfully developed and commercialized for use as individual units, development work on electromagnetic microrelay matrices where individual relays can be selectively switched on and off have been fewer and less successful. Due to inherent limitations of the micromachining processes, significant dimensional and material property variations occur among individual relays in a matrix. These variations severely limit the tolerance window and hence the reliability of operation of the device. After reviewing existing designs of electromagnetic microrelays, a set of desirable design features that would make the electromagnetic microrelay more robust are identified.  A novel design incorporating these features is proposed and preliminary results of ANSYS1 simulation studies are presented.Keywords: MEMS, microrelay and electromagnetic

  8. Design for Additive Manufacturing: Trends, opportunities, considerations, and constraints

    NARCIS (Netherlands)

    Tompson, M.K.; Moroni, G.; Vaneker, Thomas H.J.; Fadel, G.; Campbell, I.; Gibson, I.; Bernard, A.; Schulz, J.; Graf, P.; Ahuja, B.; Martina, F.

    2016-01-01

    The past few decades have seen substantial growth in Additive Manufacturing (AM) technologies. However, this growth has mainly been process-driven. The evolution of engineering design to take advantage of the possibilities afforded by AM and to manage the constraints associated with the technology h

  9. Acoustical Considerations in Planning and Design of Library Facilities.

    Science.gov (United States)

    Wrightson, Denelle; Wrightson, John M.

    1999-01-01

    Discusses acoustical demands in public libraries to consider during the design and construction process of new or renovated library space. Topics include intrusive noises; overly reverberant spaces; lack of speech privacy; sound transmission class; noise criteria; reverberation time and noise reduction coefficient; space planning; sound systems;…

  10. Additive Manufacturing Design Considerations for Liquid Engine Components

    Science.gov (United States)

    Whitten, Dave; Hissam, Andy; Baker, Kevin; Rice, Darron

    2014-01-01

    The Marshall Space Flight Center's Propulsion Systems Department has gained significant experience in the last year designing, building, and testing liquid engine components using additive manufacturing. The department has developed valve, duct, turbo-machinery, and combustion device components using this technology. Many valuable lessons were learned during this process. These lessons will be the focus of this presentation. We will present criteria for selecting part candidates for additive manufacturing. Some part characteristics are 'tailor made' for this process. Selecting the right parts for the process is the first step to maximizing productivity gains. We will also present specific lessons we learned about feature geometry that can and cannot be produced using additive manufacturing machines. Most liquid engine components were made using a two-step process. The base part was made using additive manufacturing and then traditional machining processes were used to produce the final part. The presentation will describe design accommodations needed to make the base part and lessons we learned about which features could be built directly and which require the final machine process. Tolerance capabilities, surface finish, and material thickness allowances will also be covered. Additive Manufacturing can produce internal passages that cannot be made using traditional approaches. It can also eliminate a significant amount of manpower by reducing part count and leveraging model-based design and analysis techniques. Information will be shared about performance enhancements and design efficiencies we experienced for certain categories of engine parts.

  11. Safety Considerations in the Design of Riot-Control Grenades

    Science.gov (United States)

    1982-08-01

    fuze design resulted in injuries to the user, because the user would not maintain the required pressure after removing the safety pin . The grenade...of the M25A2 grenade was the accidental functioning of the grenade with the safety pin intact. If the ferenade was dropped onto a hard surface

  12. Teachers' Considerations of Students' Thinking during Mathematics Lesson Design

    Science.gov (United States)

    Amador, Julie M.

    2016-01-01

    Teachers' abilities to design mathematics lessons are related to their capability to mobilize resources to meeting intended learning goals based on their noticing. In this process, knowing how teachers consider Students' thinking is important for understanding how they are making decisions to promote student learning. While teaching, what teachers…

  13. Design for Additive Manufacturing: Trends, opportunities, considerations, and constraints

    NARCIS (Netherlands)

    Tompson, M.K.; Moroni, G.; Vaneker, T.H.J.; Fadel, G.; Campbell, I.; Gibson, I.; Bernard, A.; Schulz, J.; Graf, P.; Ahuja, B.; Martina, F.

    2016-01-01

    The past few decades have seen substantial growth in Additive Manufacturing (AM) technologies. However, this growth has mainly been process-driven. The evolution of engineering design to take advantage of the possibilities afforded by AM and to manage the constraints associated with the technology h

  14. Design for Additive Manufacturing: Trends, opportunities, considerations, and constraints

    NARCIS (Netherlands)

    Tompson, M.K.; Moroni, G.; Vaneker, Thomas H.J.; Fadel, G.; Campbell, I.; Gibson, I.; Bernard, A.; Schulz, J.; Graf, P.; Ahuja, B.; Martina, F.

    2016-01-01

    The past few decades have seen substantial growth in Additive Manufacturing (AM) technologies. However, this growth has mainly been process-driven. The evolution of engineering design to take advantage of the possibilities afforded by AM and to manage the constraints associated with the technology

  15. Thermo-hydraulic analysis for sub-module of Chinese HCSB TBM design

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhou; FENG Kai-ming; WANG Xiao-yu; YUAN Tao

    2006-01-01

    Thermo-hydraulic calculation and analysis for sub-module of Chinese HCSB TBM were carried out using FE code ANSYS. Results indicate that temperature distribution in materials used in sub-module is reasonable and acceptable.

  16. 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.

  17. Flexible energy-storage devices: design consideration and recent progress.

    Science.gov (United States)

    Wang, Xianfu; Lu, Xihong; Liu, Bin; Chen, Di; Tong, Yexiang; Shen, Guozhen

    2014-07-23

    Flexible energy-storage devices are attracting increasing attention as they show unique promising advantages, such as flexibility, shape diversity, light weight, and so on; these properties enable applications in portable, flexible, and even wearable electronic devices, including soft electronic products, roll-up displays, and wearable devices. Consequently, considerable effort has been made in recent years to fulfill the requirements of future flexible energy-storage devices, and much progress has been witnessed. This review describes the most recent advances in flexible energy-storage devices, including flexible lithium-ion batteries and flexible supercapacitors. The latest successful examples in flexible lithium-ion batteries and their technological innovations and challenges are reviewed first. This is followed by a detailed overview of the recent progress in flexible supercapacitors based on carbon materials and a number of composites and flexible micro-supercapacitors. Some of the latest achievements regarding interesting integrated energy-storage systems are also reviewed. Further research direction is also proposed to surpass existing technological bottle-necks and realize idealized flexible energy-storage devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Design Considerations for Stand-Alone Photovoltaic (PV Cell Applications

    Directory of Open Access Journals (Sweden)

    Mehmet Cebeci

    2013-06-01

    Full Text Available Solar energy is one of the most important renewable energy sources. The photovoltaic (PV cell systems are used to convert solar energy into electricity. PV systems are divided into two as fixed systems and tracking systems. Fixed systems are mounted at a certain tilt with horizontal to make full use of sunlight. The tilt angle of PV arrays in a fixed system depends on the location and time. If this tilt angle is determined well, the amount of insolation and the energy that is generated increases. When a stand-alone PV cell system is being chosen, certain design operations should be implemented. The number of modules and batteries needed for any system should be calculated by means of the amount of load, insolation level, module characteristics, etc. The design of system is finalized according to the energy demand.

  19. Design Considerations for Human Rating of Liquid Rocket Engines

    Science.gov (United States)

    Parkinson, Douglas

    2010-01-01

    I.Human-rating is specific to each engine; a. Context of program/project must be understood. b. Engine cannot be discussed independently from vehicle and mission. II. Utilize a logical combination of design, manufacturing, and test approaches a. Design 1) It is crucial to know the potential ways a system can fail, and how a failure can propagate; 2) Fault avoidance, fault tolerance, DFMR, caution and warning all have roles to play. b. Manufacturing and Assembly; 1) As-built vs. as-designed; 2) Review procedures for assembly and maintenance periodically; and 3) Keep personnel trained and certified. c. There is no substitute for test: 1) Analytical tools are constantly advancing, but still need test data for anchoring assumptions; 2) Demonstrate robustness and explore sensitivities; 3) Ideally, flight will be encompassed by ground test experience. III. Consistency and repeatability is key in production a. Maintain robust processes and procedures for inspection and quality control based upon development and qualification experience; b. Establish methods to "spot check" quality and consistency in parts: 1) Dedicated ground test engines; 2) Random components pulled from the line/lot to go through "enhanced" testing.

  20. Design and construction considerations for light steel structures

    Directory of Open Access Journals (Sweden)

    G. P.J. de Vos

    2001-09-01

    Full Text Available Many alternative structural systems have recently been proposed in South Africa in an attempt to reduce costs of lightweight steel structures. Most of these comprise premanufactured components which are bolted together on site. Large industrial type structures are usually constructed with hot-rolled steel profiles, so that, apart from the architect, a structural engineer, manufacturer and contractor would be required. As an alternative to these existing practices, this article proposes design and construction techniques that may reduce the cost of the structure and at the same time create employment for emerging contractors. The proposed construction method consists of the welding together of lightweight profiles on site. For the structure the following is proposed: short pile  footings to provide partial fixidity to the structure, effective and lightweight compositions of cold-formed thin-walled profiles for structural elements, and stressed skin diaphragm design wherein the cladding, purlins and structural elements work together as one unit. Alternative portal frame configurations were analysed and designed to form larger structures, which indicates the versatility of the proposed construction concept. The article further illustrates that the utilization of the proposed construction method results in more economical structures and discusses applications of the principles on a number of real structures.

  1. Hemodynamics in Idealized Stented Coronary Arteries: Important Stent Design Considerations.

    Science.gov (United States)

    Beier, Susann; Ormiston, John; Webster, Mark; Cater, John; Norris, Stuart; Medrano-Gracia, Pau; Young, Alistair; Cowan, Brett

    2016-02-01

    Stent induced hemodynamic changes in the coronary arteries are associated with higher risk of adverse clinical outcome. The purpose of this study was to evaluate the impact of stent design on wall shear stress (WSS), time average WSS, and WSS gradient (WSSG), in idealized stent geometries using computational fluid dynamics. Strut spacing, thickness, luminal protrusion, and malapposition were systematically investigated and a comparison made between two commercially available stents (Omega and Biomatrix). Narrower strut spacing led to larger areas of adverse low WSS and high WSSG but these effects were mitigated when strut size was reduced, particularly for WSSG. Local hemodynamics worsened with luminal protrusion of the stent and with stent malapposition, adverse high WSS and WSSG were identified around peak flow and throughout the cardiac cycle respectively. For the Biomatrix stent, the adverse effect of thicker struts was mitigated by greater strut spacing, radial cell offset and flow-aligned struts. In conclusion, adverse hemodynamic effects of specific design features (such as strut size and narrow spacing) can be mitigated when combined with other hemodynamically beneficial design features but increased luminal protrusion can worsen the stent's hemodynamic profile significantly.

  2. Design and fabrication considerations of EUVL collectors for HVM

    Science.gov (United States)

    Bianucci, G.; Cassol, G. L.; Kools, J.; Prea, M.; Salmaso, G.; Valsecchi, G.; Zocchi, F. E.; Bolshukhin, D.; Schürmann, M.; Schriever, G.; Mader, A.; Zink, P.

    2009-03-01

    The power roadmap for EUVL high volume manufacturing (HVM) exceeds the 200W EUV in-band power at intermediate focus, thus posing more demanding requirements on HVM sources, debris suppression systems and collectors. Starting from the lessons learned in the design and fabrication of the grazing incidence collectors for the Alpha EUVL scanners, Media Lario Technologies is developing HVM optical solutions that enable designed-in lifetime improvements, such as larger source-collector distances, optimized collection efficiency through larger collected solid angles, and customized EUV reflective layers. The optical design of an HVM collector is described together with the selection of the sacrificial ruthenium reflective layer. The water cooling layout of the collector is evolved from the integrated cooling technology developed at Alpha level into an innovative cooling layout that minimizes the thermal gradients across the mirrors and allows controlling the optical performance at the far-field plane. Finally, the evolution of the collector's manufacturing technologies for HVM is discussed. XTREME technologies and Philips Extreme UV support this work by integrating the collector in the complete source collector module (SoCoMo). At system level, each component of the SoCoMo is part of a development and improvement plan leading to a comprehensive system that will fulfill the 200+ W EUV in-band power at intermediate focus.

  3. Mixed-flow vertical tubular hydraulic turbine. Determination of proper design duty point

    Energy Technology Data Exchange (ETDEWEB)

    Sirok, B. [Ljubljana Univ. (Slovenia). Faculty of Mechanical Engineering; Bergant, A. [Litostroj Power, d.o.o., Ljubljana (Slovenia); Hoefler, E.

    2011-12-15

    A new vertical single-regulated mixed-flow turbine with conical guide apparatus and without spiral casing is presented in this paper. Runner blades are fixed to the hub and runner band and resemble to the Francis type runner of extremely high specific speed. Due to lack of information and guidelines for the design of a new turbine, a theoretical model was developed in order to determinate the design duty point, i.e. to determine the optimum narrow operation range of the turbine. It is not necessary to know the kinematic conditions at the runner inlet, but only general information on the geometry of turbine flow-passage, meridional contour of the runner and blading, the number of blades and the turbine speed of rotation. The model is based on the integral tangential lift coefficient, which is the average value over the entire runner blading. The results are calculated for the lift coefficient 0.5 and 0.6, for the flow coefficient range from 0.2 to 0.36, for the number of the blades between 5 and 13, and are finally presented in the Cordier diagram (specific speed vs. specific diameter). Calculated results of the turbine optimum operation in Cordier diagram correspond very well to the adequate area of Kaplan turbines with medium and low specific speed and extends into the area of Francis turbines with high specific speed. Presented model clearly highlights the parameters that affect specific load of the runner blade row and therefore the optimum turbine operation (discharge - turbine head). The presented method is not limited to a specific reaction type of the hydraulic turbine. The method can therefore be applied to a wide range from mixed-flow (radial-axial) turbines to the axial turbines. Applicability of the method may be considered as a tool in the first stage of the turbine design i.e. when designing the meridional geometry and selecting the number of blades according to calculated operating point. Geometric and energy parameters are generally defined to an

  4. Modeling and design of cooperative braking in electric and hybrid vehicles using induction machine and hydraulic brake

    Directory of Open Access Journals (Sweden)

    Zaini Dalimus

    2016-07-01

    Full Text Available In mixed-mode braking applications, the electric motor / generator (M/G and hydraulic pressure valve are controlled to meet the driver’s braking demand. Controlling these braking elements is achieved by modulating the current generated by the M/G and adjusting the fluid pressure to the wheel brake cylinders. This paper aims to model and design combined regenerative and hydraulic braking systems which, comprise an induction electric machine, inverter, NiMH battery, controller, a pressure source, pressure control unit, and brake calipers. A 15 kW 1500 rpm induction machine equipped with a reduction gear having a gear ratio of 4 is used. A hydraulic brake capable to produce fluid pressure up to 40 bar is used. Direct torque control and pressure control are chosen as the control criteria in the M/G and the hydraulic solenoid valve. The braking demands for the system are derived from the Federal Testing Procedure (FTP drive cycle. Two simulation models have been developed in Matlab®/Simulink® to analyze the performance of the control strategy in each braking system. The developed model is validated through experiment. It is concluded that the control system does introduce torque ripple and pressure oscillation in the braking system, but these effects do not affect vehicle braking performance due to the high frequency nature of pressure fluctuation and the damping effect of the vehicle inertia. Moreover, experiment results prove the effectiveness of the developed model.

  5. Antenna Design Considerations for the Advanced Extravehicular Mobility Unit

    Science.gov (United States)

    Bakula, Casey J.; Theofylaktos, Onoufrios

    2015-01-01

    NASA is designing an Advanced Extravehicular Mobility Unit (AEMU)to support future manned missions beyond low-Earth orbit (LEO). A key component of the AEMU is the communications assembly that allows for the wireless transfer of voice, video, and suit telemetry. The Extravehicular Mobility Unit (EMU) currently used on the International Space Station (ISS) contains a radio system with a single omni-directional resonant cavity antenna operating slightly above 400 MHz capable of transmitting and receiving data at a rate of about 125 kbps. Recent wireless communications architectures are calling for the inclusion of commercial wireless standards such as 802.11 that operate in higher frequency bands at much higher data rates. The current AEMU radio design supports a 400 MHz band for low-rate mission-critical data and a high-rate band based on commercial wireless local area network (WLAN) technology to support video, communication with non-extravehicular activity (EVA) assets such as wireless sensors and robotic assistants, and a redundant path for mission-critical EVA data. This paper recommends the replacement of the existing EMU antenna with a new antenna that maintains the performance characteristics of the current antenna but with lower weight and volume footprints. NASA has funded several firms to develop such an antenna over the past few years, and the most promising designs are variations on the basic patch antenna. This antenna technology at UHF is considered by the authors to be mature and ready for infusion into NASA AEMU technology development programs.

  6. Design considerations for an air core magnetic actuator

    Science.gov (United States)

    Groom, Nelson J.

    1992-01-01

    Equations for the force produced by an air core electromagnet on a permanent magnet core as a function of the coil height, coil inner and outer radii, and core displacement are developed. The magnetization vector of the permanent magnet core is assumed to be aligned with the central axis of the electromagnet and the forces which are produced lie along the same axis. Variations in force due to changes in electromagnet parameters and core displacement are investigated and parameter plots which should be useful for coil design are presented.

  7. Design considerations for a low-noise CMOS image sensor

    Science.gov (United States)

    González-Márquez, Ana; Charlet, Alexandre; Villegas, Alberto; Jiménez-Garrido, Francisco; Medeiro, Fernando; Domínguez-Castro, Rafael; Rodríguez-Vázquez, Ángel

    2015-03-01

    This paper reports a Low-Noise CMOS Image Sensor. Low-noise operation is achieved owing to the combination of a noise-enhanced pixel, the use of a two-step ADC architecture and the analysis, and the optimization thereof, of the noise contributed by the readout channel. The paper basically gathers the sensor architecture, the ADC converter architecture, the outcome of the noise analysis and some basic characterization data. The general low-noise design framework is discussed in the companion presentation.

  8. Considerations of Protein Subpockets in Fragment-Based Drug Design.

    Science.gov (United States)

    Bartolowits, Matthew; Davisson, V Jo

    2016-01-01

    While the fragment-based drug design approach continues to gain importance, gaps in the tools and methods available in the identification and accurate utilization of protein subpockets have limited the scope. The importance of these features of small molecule-protein recognition is highlighted with several examples. A generalized solution for the identification of subpockets and corresponding chemical fragments remains elusive, but there are numerous advancements in methods that can be used in combination to address subpockets. Finally, additional examples of approaches that consider the relative importance of small-molecule co-dependence of protein conformations are highlighted to emphasize an increased significance of subpockets, especially at protein interfaces.

  9. Trends in Modelling, Simulation and Design of Water Hydraulic Systems – Motion Control and Open-Ended Solutions

    DEFF Research Database (Denmark)

    Conrad, Finn

    2006-01-01

    The paper presents and discusses a R&D-view on trends in development and best practise in modelling, simulation and design of both low-pressure and high-pressure tap water hydraulic components and systems for motion control as well as open-ended solutions various industrial applications. The focus...... is on the advantages using ordinary tap water and the range of application areas are illustrated with examples, in particular within the food processing industry, humidification operations, water mist systems for fire fighting, high water pressure cleaners, water moisturising systems for wood processing, lumber drying...... is that the components operate with pure water from the tap without additives of any kind. Hence water hydraulics takes the benefit of pure water as fluid being environmentally friendly, easy to clean sanitary design, non-toxic, non-flammable, inexpensive, readily available and easily disposable. The low-pressure tap...

  10. Design and market considerations for axial flux superconducting electric machine design

    CERN Document Server

    Ainslie, Mark D; Shaw, Robert; Dawson, Lewis; Winfield, Andy; Steketee, Marina; Stockley, Simon

    2013-01-01

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. This work was carried out as part of the University of Cambridge's Centre for Entrepreneurial Learning ETECH Project programme, designed to accelerate entrepreneurship and diffusion of innovations based on early stage and potentially disruptive technologies from the University. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricin...

  11. System-Level Design Considerations for Carbon Nanotube Electromechanical Resonators

    Directory of Open Access Journals (Sweden)

    Christian Kauth

    2013-01-01

    Full Text Available Despite an evermore complete plethora of complex domain-specific semiempirical models, no succinct recipe for large-scale carbon nanotube electromechanical systems design has been formulated. To combine the benefits of these highly sensitive miniaturized mechanical sensors with the vast functionalities available in electronics, we identify a reduced key parameter set of carbon nanotube properties, nanoelectromechanical system design, and operation that steers the sensor’s performance towards system applications, based on open- and closed-loop topologies. Suspended single-walled carbon nanotubes are reviewed in terms of their electromechanical properties with the objective of evaluating orders of magnitude of the electrical actuation and detection mechanisms. Open-loop time-averaging and 1ω or 2ω mixing methods are completed by a new 4ω actuation and detection technique. A discussion on their extension to closed-loop topologies and system applications concludes the analysis, covering signal-to-noise ratio, and the capability to spectrally isolate the motional information from parasitical feedthrough by contemporary electronic read-out techniques.

  12. Mental and behavioral health environments: critical considerations for facility design.

    Science.gov (United States)

    Shepley, Mardelle McCuskey; Watson, Angela; Pitts, Francis; Garrity, Anne; Spelman, Elizabeth; Kelkar, Janhawi; Fronsman, Andrea

    2016-01-01

    The purpose of the study was to identify features in the physical environment that are believed to positively impact staff and patients in psychiatric environments and use these features as the foundation for future research regarding the design of mental and behavioral health facilities. Pursuant to a broad literature review that produced an interview script, researchers conducted 19 interviews of psychiatric staff, facility administrators and architects. Interview data were analyzed using the highly structured qualitative data analysis process authored by Lincoln and Guba (1985). Seventeen topics were addressed ranging from the importance of a deinstitutionalized environment to social interaction and autonomy. The interviewees reinforced the controversy that exists around the implications of a deinstitutionalized environment, when the resulting setting diminishes patient and staff safety. Respondents tended to support open nurse stations vs. enclosed stations. Support for access to nature and the provision of an aesthetic environment was strong. Most interviewees asserted that private rooms were highly desirable because lower room density reduces the institutional character of a unit. However, a few interviewees adamantly opposed private rooms because they considered the increased supervision of one patient by another to be a deterrent to self-harm. The need to address smoking rooms in future research received the least support of all topics. Responses of interviews illustrate current opinion regarding best practice in the design of psychiatric facilities. The findings emphasize the need for more substantive research on appropriate physical environments in mental and behavioral health settings. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Design Considerations for Space Transfer Vehicles Using Solar Thermal Propulsion

    Science.gov (United States)

    Emrich, William J.

    1995-01-01

    The economical deployment of satellites to high energy earth orbits is crucial to the ultimate success of this nations commerical space ventures and is highly desirable for deep space planetary missions requiring earth escape trajectories. Upper stage space transfer vehicles needed to accomplish this task should ideally be simple, robust, and highly efficient. In this regard, solar thermal propulsion is particularly well suited to those missions where high thrust is not a requirement. The Marshall Space Flight Center is , therefore, currently engaged in defining a transfer vehicle employing solar thermal propulsion capable of transferring a 1000 lb. payload from low Earth orbit (LEO) to a geostationary Earth orbit (GEO) using a Lockheed launch vehicle (LLV3) with three Castors and a large shroud. The current design uses liquid hydrogen as the propellant and employs two inflatable 16 x 24 feet eliptical off-axis parabolic solar collectors to focus sunlight onto a tungsten/rhenium windowless black body type absorber. The concentration factor on this design is projected to be approximately 1800:1 for the primary collector and 2.42:1 for the secondary collector for an overall concentration factor of nearly 4400:1. The engine, which is about twice as efficient as the best currently available chemical engines, produces two pounds of thrust with a specific impulse (Isp) of 860 sec. Transfer times to GEO are projected to be on the order of one month. The launch and deployed configurations of the solar thermal upper stage (STUS) are depicted.

  14. Design Considerations, Modeling and Analysis for the Multispectral Thermal Imager

    Energy Technology Data Exchange (ETDEWEB)

    Borel, C.C.; Clodius, W.B.; Cooke, B.J.; Smith, B.W.; Weber, P.G.

    1999-02-01

    The design of remote sensing systems is driven by the need to provide cost-effective, substantive answers to questions posed by our customers. This is especially important for space-based systems, which tend to be expensive, and which generally cannot be changed after they are launched. We report here on the approach we employed in developing the desired attributes of a satellite mission, namely the Multispectral Thermal Imager. After an initial scoping study, we applied a procedure which we call: "End-to-end modeling and analysis (EEM)." We began with target attributes, translated to observable signatures and then propagated the signatures through the atmosphere to the sensor location. We modeled the sensor attributes to yield a simulated data stream, which was then analyzed to retrieve information about the original target. The retrieved signature was then compared to the original to obtain a figure of merit: hence the term "end-to-end modeling and analysis." We base the EEM in physics to ensure high fidelity and to permit scaling. As the actual design of the payload evolves, and as real hardware is tested, we can update the EEM to facilitate trade studies, and to judge, for example, whether components that deviate from specifications are acceptable.

  15. Biomechanical considerations in the design of graft: the homeostasis hypothesis.

    Science.gov (United States)

    Kassab, Ghassan S; Navia, José A

    2006-01-01

    Since its inception in the 1960s, coronary artery bypass graft (CABG) evolved as one of the most common, best documented, and most effective of all major surgical treatments for ischemic heart disease. Despite its widespread use, however, the outcome is not always completely satisfactory. The objective of this review is to highlight the physical determinants of biomechanical design of CABG so that future procedures would have prolonged patency and better outcome. Our central axiom postulates the existence of a mechanical homeostatic state of the blood vessel, i.e., the variation in vessel wall stresses and strains are relatively small under physiological conditions. Any perturbation of mechanical homeostasis leads to growth and remodeling. In this sense, stenosis and failure of a graft may be viewed as an adaptation process gone awry. We outline the principles of engineering design and discuss the biofluid and biosolid mechanics principles that may have the greatest bearing on mechanical homeostasis and the long-term outcome of CABG.

  16. SPOUTED BED DESIGN CONSIDERATIONS FOR COATED NUCLEAR FUEL PARTICLES

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Douglas W.

    2017-07-01

    High Temperature Gas Cooled Reactors (HTGRs) are fueled with tristructural isotropic (TRISO) coated nuclear fuel particles embedded in a carbon-graphite fuel body. TRISO coatings consist of four layers of pyrolytic carbon and silicon carbide that are deposited on uranium ceramic fuel kernels (350µm – 500µm diameters) in a concatenated series of batch depositions. Each layer has dedicated functions such that the finished fuel particle has its own integral containment to minimize and control the release of fission products into the fuel body and reactor core. The TRISO coatings are the primary containment structure in the HTGR reactor and must have very high uniformity and integrity. To ensure high quality TRISO coatings, the four layers are deposited by chemical vapor deposition (CVD) using high purity precursors and are applied in a concatenated succession of batch operations before the finished product is unloaded from the coating furnace. These depositions take place at temperatures ranging from 1230°C to 1550°C and use three different gas compositions, while the fuel particle diameters double, their density drops from 11.1 g/cm3 to 3.0 g/cm3, and the bed volume increases more than 8-fold. All this is accomplished without the aid of sight ports or internal instrumentation that could cause chemical contamination within the layers or mechanical damage to thin layers in the early stages of each layer deposition. The converging section of the furnace retort was specifically designed to prevent bed stagnation that would lead to unacceptably high defect fractions and facilitate bed circulation to avoid large variability in coating layer dimensions and properties. The gas injection nozzle was designed to protect precursor gases from becoming overheated prior to injection, to induce bed spouting and preclude bed stagnation in the bottom of the retort. Furthermore, the retort and injection nozzle designs minimize buildup of pyrocarbon and silicon carbide on the

  17. 粉末制品成形液压机的设计%Design of hydraulic press for powder products

    Institute of Scientific and Technical Information of China (English)

    李响

    2012-01-01

    As per the technical requirement of press forming process for powder products, the key design points of hydraulic press for powder products with high performance have been briefly introduced.%针对粉末制品压坯成形的工艺要求,简要介绍了高性能粉末制品成形液压机的设计要点.

  18. Design Considerations for High Energy Electron -- Positron Storage Rings

    Science.gov (United States)

    Richter, B.

    1966-11-01

    High energy electron-positron storage rings give a way of making a new attack on the most important problems of elementary particle physics. All of us who have worked in the storage ring field designing, building, or using storage rings know this. The importance of that part of storage ring work concerning tests of quantum electrodynamics and mu meson physics is also generally appreciated by the larger physics community. However, I do not think that most of the physicists working tin the elementary particle physics field realize the importance of the contribution that storage ring experiments can make to our understanding of the strongly interacting particles. I would therefore like to spend the next few minutes discussing the sort of things that one can do with storage rings in the strongly interacting particle field.

  19. Design Considerations for Optimized Lateral Spring Structures for Wearable Electronics

    KAUST Repository

    Hussain, Aftab M.

    2016-03-07

    The market for wearable electronics has been gaining momentum in the recent years. For completely electronic wearable textiles with integrated sensors, actuators, computing units and communication circuitry, it is important that there is significant stretchability. This stretchability can be obtained by introducing periodic stretchable structures between the electronic circuits. In this work, we derive the equations and constraints governing the stretchability in horseshoe lateral spring structures. We have derived the optimum design and the parameters therein, to help develop the best spring structures for a given stretchability. We have also developed a figure of merit, called area efficiency of stretchability, to compare all twodimensional stretchable systems. Finally, we experimentally verify the validity of our equations by fabricating a metal/polymer bilayer thin film based stretchable horseshoe lateral spring structures. We obtain a stretchability of 1.875 which is comparable to the theoretical maxima of 2.01 for the given parameters.

  20. Design and implementation considerations of a MSAT packet data network

    Science.gov (United States)

    Karam, Fouad G.; Hearn, Terry; Rohr, Doug; Guibord, Arthur F.

    The Mobile Data System, which is intended to provide for packet switched data services is currently under development. The system is based on a star network topology consisting of a centralized Data Hub (DH) serving a large number of mobile terminals. Through the Data Hub, end-to-end connections can be established between terrestrial users on public or private data networks and mobile users. The MDS network will be capable of offering a variety of services some of which are based on the standard X.25 network interface protocol, and others optimized for short messages and broadcast messages. A description of these services and the trade-offs in the DH design are presented.

  1. Some design considerations for small piezo-electrical ceramic transducers

    Science.gov (United States)

    Rijnja, H. A. J.

    1989-07-01

    The design parameters and the characteristics of small omnidirectional transducers, to be applied under water as projectors in the frequency range of about 1 kHz to 100 kHz and as hydrophones from very low frequencies up to again 100kHz are described. The transducers are constructed with piezoelectrical ceramic materials in the shape of hollow spheres, end capped tubes or piston (Tonpilz) elements. The highest source levels are obtained with spherical transducers as single omnidirectional sound sources. If larger arrays of sources are applied the array should be composed of single ended Tonpilz elements. The most sensitive receivers (hydrophones) are obtained with tangentially polarized end-capped tubes.

  2. Fuel-cell powered uninterruptible power supply systems: Design considerations

    Science.gov (United States)

    Choi, Woojin; Howze, Jo. W.; Enjeti, Prasad

    A 1-kVA fuel cell powered, line-interactive uninterruptible power supply (UPS) system that employs modular (fuel cell and power converter) blocks is introduced. Two commercially available proton-exchange membrane fuel cell (25-39 V, 500 W) modules together with suitable dc-dc and dc-ac power electronic converter modules are employed. A supercapacitor module is also used to compensate for the instantaneous power fluctuations and to overcome the slow dynamics of the fuel processor (reformers). Further energy stored in the supercapacitor is also utilized to handle a momentary overload such as 200% for a short duration. Due to the absence of batteries, the system satisfies the demand for an environmentally clean source of energy. A complete design that defines the amount of hydrogen storage required for a power outage of 1 h, and the sizing of the supercapacitors for transient load demand is presented for a 1-kVA UPS.

  3. Technicon H*1 Hematology System: Optical Design Considerations

    Science.gov (United States)

    Colella, G. M.; Tycko, D. H.; Groner, W.

    1988-06-01

    The Technicon H*1 systemTM is a clinical laboratory flow cytometer which performs a complete hematology profile, providing quantitative information on the various types of cells in a blood sample. A light-scattering method, using a HeNe laser, determines in a single flow channel the red cell count, platelet count, and the distributions of red cell volume, red cell hemoglobin concentration, and platelet volume. To accomplish this the scattered light from each red cell in the sample is measured in real time at two angular intervals. The cell volume and the hemoglobin concentration within the cell are derived from these two measurements. Severe accuracy and precision specifications are placed on the medically important red cell count (RBC) and the mean red cell volume (MCV). From the point of view of optical system design, the dominant factor is the requirement that RBC and MCV have precision and accuracy of the order of 2%. Signal-to-noise and scattering-angle definition requirements dictated the choice of a HeNe laser light source. The optics includes an illumination system for producing a sharply defined, uniformly illuminated scattering region and a detection system which must accurately define the accepted scattering angles. In previous cytometric methods for determining MCV only a single quantity was measured for each cell. Such methods cannot disentangle the independent effects of cell size and hemoglobin concentration on the measurement, thus compromising MCV accuracy. The present double-angle scattering method overcomes this accuracy problem. The H*1 red cell method, the supporting optical design and data demonstrating that the use of this technique eliminates interference between the observed red cell indices are presented.

  4. Ultra-long fiber Raman lasers: design considerations

    Science.gov (United States)

    Koltchanov, I.; Kroushkov, D. I.; Richter, A.

    2015-03-01

    In frame of the European Marie Currie project GRIFFON [http://astonishgriffon.net/] the usage of a green approach in terms of reduced power consumption and maintenance costs is envisioned for long-span fiber networks. This shall be accomplished by coherent transmission in unrepeatered links (100 km - 350 km) utilizing ultra-long Raman fiber laser (URFL)-based distributed amplification, multi-level modulation formats, and adapted Digital Signal Processing (DSP) algorithms. The URFL uses a cascaded 2-order pumping scheme where two (co- and counter-) ˜ 1365 nm pumps illuminate the fiber. The URFL oscillates at ˜ 1450 nm whereas amplification is provided by stimulated Raman scattering (SRS) of the ˜ 1365 nm pumps and the optical feedback is realized by two Fiber Bragg gratings (FBGs) at the fiber ends reflecting at 1450 nm. The light field at 1450 nm provides amplification for signal waves in the 1550 nm range due to SRS. In this work we present URFL design studies intended to characterize and optimize the power and noise characteristics of the fiber links. We use a bidirectional fiber model describing propagation of the signal, pump and noise powers along the fiber length. From the numerical solution we evaluate the on/off Raman gain and its bandwidth, the signal excursion over the fiber length, OSNR spectra, and the accumulated nonlinearities. To achieve best performance for these characteristics the laser design is optimized with respect to the forward/backward pump powers and wavelengths, input/output signal powers, reflectivity profile of the FBGs and other parameters.

  5. 液压机液压系统过滤器的选择与设计%Selection and design of hydraulic filter for hydraulic press

    Institute of Scientific and Technical Information of China (English)

    崔景海

    2012-01-01

    维护油液清洁对液压机液压系统十分重要.介绍了液压机液压系统中常用过滤器的种类及过滤器选型时应考虑的因素.%The cleanliness of the hydraulic oil is very important to the hydraulic system of hydraulic press.There are four common kinds of filter used in hydraulic system of hydraulic press as follows: high pressure filter,low pressure filter,water pressure filter,and air filter.Entry and exit size of filters,nominal pressure,filtering precision,and filter material should have been considered in the selection of the filter.

  6. Materials for Consideration in Standardized Canister Design Activities.

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R.; Ilgen, Anastasia Gennadyevna; Enos, David George; Teich-McGoldrick, Stephanie; Hardin, Ernest

    2014-10-01

    This document identifies materials and material mitigation processes that might be used in new designs for standardized canisters for storage, transportation, and disposal of spent nuclear fuel. It also addresses potential corrosion issues with existing dual-purpose canisters (DPCs) that could be addressed in new canister designs. The major potential corrosion risk during storage is stress corrosion cracking of the weld regions on the 304 SS/316 SS canister shell due to deliquescence of chloride salts on the surface. Two approaches are proposed to alleviate this potential risk. First, the existing canister materials (304 and 316 SS) could be used, but the welds mitigated to relieve residual stresses and/or sensitization. Alternatively, more corrosion-resistant steels such as super-austenitic or duplex stainless steels, could be used. Experimental testing is needed to verify that these alternatives would successfully reduce the risk of stress corrosion cracking during fuel storage. For disposal in a geologic repository, the canister will be enclosed in a corrosion-resistant or corrosion-allowance overpack that will provide barrier capability and mechanical strength. The canister shell will no longer have a barrier function and its containment integrity can be ignored. The basket and neutron absorbers within the canister have the important role of limiting the possibility of post-closure criticality. The time period for corrosion is much longer in the post-closure period, and one major unanswered question is whether the basket materials will corrode slowly enough to maintain structural integrity for at least 10,000 years. Whereas there is extensive literature on stainless steels, this evaluation recommends testing of 304 and 316 SS, and more corrosion-resistant steels such as super-austenitic, duplex, and super-duplex stainless steels, at repository-relevant physical and chemical conditions. Both general and localized corrosion testing methods would be used to

  7. 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.

  8. Design Considerations for RNA Spherical Nucleic Acids (SNAs).

    Science.gov (United States)

    Barnaby, Stacey N; Perelman, Grant A; Kohlstedt, Kevin L; Chinen, Alyssa B; Schatz, George C; Mirkin, Chad A

    2016-09-21

    Ribonucleic acids (RNAs) are key components in many cellular processes such as cell division, differentiation, growth, aging, and death. RNA spherical nucleic acids (RNA-SNAs), which consist of dense shells of double-stranded RNA on nanoparticle surfaces, are powerful and promising therapeutic modalities because they confer advantages over linear RNA such as high cellular uptake and enhanced stability. Due to their three-dimensional shell of oligonucleotides, SNAs, in comparison to linear nucleic acids, interact with the biological environment in unique ways. Herein, the modularity of the RNA-SNA is used to systematically study structure-function relationships in order to understand how the oligonucleotide shell affects interactions with a specific type of biological environment, namely, one that contains serum nucleases. We use a combination of experiment and theory to determine the key architectural properties (i.e., sequence, density, spacer moiety, and backfill molecule) that affect how RNA-SNAs interact with serum nucleases. These data establish a set of design parameters for SNA architectures that are optimized in terms of stability.

  9. Design Considerations for Array CGH to OligonucleotideArrays

    Energy Technology Data Exchange (ETDEWEB)

    Baldocchi, R.A.; Glynne, R.J.; Chin, K.; Kowbel, D.; Collins, C.; Mack, D.H.; Gray, J.W.

    2005-03-04

    Background: Representational oligonucleotide microarray analysis has been developed for detection of single nucleotide polymorphisms and/or for genome copy number changes. In this process, the intensity of hybridization to oligonucleotides arrays is increased by hybridizing a polymerase chain reaction (PCR)-amplified representation of reduced genomic complexity. However, hybridization to some oligonucleotides is not sufficiently high to allow precise analysis of that portion of the genome. Methods: In an effort to identify aspects of oligonucleotide hybridization affecting signal intensity, we explored the importance of the PCR product strand to which each oligonucleotide is homologous and the sequence of the array oligonucleotides. We accomplished this by hybridizing multiple PCR-amplified products to oligonucleotide arrays carrying two sense and two antisense 50-mer oligonucleotides for each PCR amplicon. Results: In some cases, hybridization intensity depended more strongly on the PCR amplicon strand (i.e., sense vs. antisense) than on the detection oligonucleotide sequence. In other cases, the oligonucleotide sequence seemed to dominate. Conclusion: Oligonucleotide arrays for analysis of DNA copy number or for single nucleotide polymorphism content should be designed to carry probes to sense and antisense strands of each PCR amplicon to ensure sufficient hybridization and signal intensity.

  10. Design considerations and modifications on an optomechatronic load cell

    Science.gov (United States)

    Camacho P., Alma A.; Martínez Serrano, Francisco Javier; García D., Osvaldo M.

    2011-10-01

    We have divided this project in stages the first being the construction of an optomechatronics load cell1, the operating principle is based on the fact that the application on a mechanical load produces a deformation on that element. This deformation causes a reduction in the distance between the transmitter and receiver, resulting in a change in the electrical signal. It should be noted that the distribution of light intensity varies between sender and receiver due to the displacement generated. In a load cell, it was adapted an infrared emitter whose signal is received by the detector at the other end. The second stage was the demonstration that our system is able to measure external loads on a mechanical device through an indirect method for measuring stresses, which we present results generated from the experimental trials with adequate mechanical equipment in the cited work. We have implemented a strain sensitive prototype. As a result of the first and second stages to implement the system is to test it on academic applications and then adapt it to industrial environment. Note that the third stage there was a validation of the optomecatronic load cell with ASTM E74-061-2 shows the result with the basic metrological characteristics of resolution, sensitivity, repeatability, which requires it. We are currently analyzing other mechanical design proposals to improve their elastic behavior and the efficiency of this measurement system, because they increase the range of load values at which the expected response should be linear.

  11. Consideration of plant behaviour in optimal servo-compensator design

    Science.gov (United States)

    Moase, W. H.; Manzie, C.

    2016-07-01

    Where the most prevalent optimal servo-compensator formulations penalise the behaviour of an error system, this paper considers the problem of additionally penalising the actual states and inputs of the plant. Doing so has the advantage of enabling the penalty function to better resemble an economic cost. This is especially true of problems where control effort needs to be sensibly allocated across weakly redundant inputs or where one wishes to use penalties to soft-constrain certain states or inputs. It is shown that, although the resulting cost function grows unbounded as its horizon approaches infinity, it is possible to formulate an equivalent optimisation problem with a bounded cost. The resulting optimisation problem is similar to those in earlier studies but has an additional 'correction term' in the cost function, and a set of equality constraints that arise when there are redundant inputs. A numerical approach to solve the resulting optimisation problem is presented, followed by simulations on a micro-macro positioner that illustrate the benefits of the proposed servo-compensator design approach.

  12. Design and market considerations for axial flux superconducting electric machine design

    Science.gov (United States)

    Ainslie, M. D.; George, A.; Shaw, R.; Dawson, L.; Winfield, A.; Steketee, M.; Stockley, S.

    2014-05-01

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricing for conventional turbines. Next, a study is also carried out on the machine's applicability as an in-wheel hub motor for electric vehicles. Some recommendations for future applications are made based on the outcome of these two studies. Finally, the cost of YBCO-based superconducting (2G HTS) wire is analysed with respect to competing wire technologies and compared with current conventional material costs and current wire costs for both 1G and 2G HTS are still too great to be economically feasible for such superconducting devices.

  13. Nuclear Design Considerations for Z-IFE Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Meier, W R; Schmitt, R C; Abbott, R P; Latkowski, J F; Reyes, S

    2005-02-02

    Z-pinch driven IFE (Z-IFE) requires the design of a repetitive target insertion system that allows coupling of the pulsed power to the target with adequate standoff, and a chamber that can withstand blast and radiation effects from large yield targets. The present strategy for Z-IFE is to use high yield targets ({approx}2-3 GJ/shot), low repetition rate per chamber ({approx}0.1 Hz), and 10 chambers per power plant. In this study, we propose an alternative power plant configuration that uses very high yield targets (20 GJ/shot) in a single chamber operating at 0.1 Hz. A thick-liquid-wall chamber is proposed to absorb the target emission (x-rays, debris and neutrons) and mitigate the blast effects on the chamber wall. The target is attached to the end of a conical shaped Recyclable Transmission Line (RTL) made from a solid coolant (e.g., frozen flibe), or a material that is easily separable from the coolant (e.g., steel). The RTL/target assembly is inserted through a single opening at the top of the chamber for each shot. This study looks at the RTL material choice from a safety and environmental point of view. Materials were assessed according to waste disposal rating (WDR) and contact dose rate (CDR). Neutronics calculations, using the TART2002 Monte Carlo code from Lawrence Livermore National Laboratory (LLNL), were performed for the RTL and Z-IFE chamber, and key results reported here.

  14. Design, Optimization and Analysis of Hydraulic Soft Yaw System for 5 MW Wind Turbine

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.

    2011-01-01

    presents work previous done on this subject with focus on hydraulic yaw systems. 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. Results show that a significant...... reduction in fatigue and extreme loads to the yaw system and rotor shaft are possible, 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. The duty cycles, based...... on the extrapolated loads, show that it is possible to construct a hydraulic soft yaw system, which is able to reduce the loads on the wind turbine significantly....

  15. Design of Hydraulic System for Embedded Double Pipes Amphibious Crane%内嵌双输油管两用起重机液压系统设计

    Institute of Scientific and Technical Information of China (English)

    卢志珍; 倪学虎; 舒希勇; 王成龙

    2012-01-01

    Based on analyzing requirements of embedded double pipes amphibious crane to hydraulic system, the hydraulic system design thinking was put forward according to crane technical parameters and customers requirements. Calculations and type selections of the key hydraulic components; hydraulic pump and hydraulic motor, hydraulic cylinder, were completed. The hydraulic principle diagram was designed and the work principle of the hydraulic loop was expounded.%在分析内嵌双输油管两用起重机对液压系统要求的基础上,针对起重机技术参数及客户要求提出了液压系统设计的思路,对关键液压元件——液压泵、液压马达、液压缸进行了计算选型,给出了液压原理图,并阐述了起重机液压回路的工作原理.

  16. Development of modelling tools for thermo-hydraulic analyses and design of JT-60SA TF coils

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, Benoit, E-mail: benoit.lacroix@cea.fr [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Portafaix, Christophe [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Barabaschi, Pietro [Fusion For Energy, D-85748 Garching (Germany); Duchateau, Jean-Luc; Hertout, Patrick; Lamaison, Valerie; Nicollet, Sylvie; Reynaud, Pascal [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Villari, Rosaria [Euratom-ENEA Association, IT-00044 Frascati (Italy); Zani, Louis [Fusion For Energy, D-85748 Garching (Germany)

    2011-10-15

    In the framework of the JT-60SA project, the Toroidal Field (TF) coils design has required to address reliably the choice between multiple design options and to calculate the temperature margin criterion for the superconductor. For this purpose, a tool was developed in two stages, interfacing the ANSYS code, used to model the thermal diffusion between the casing and the winding pack, with the GANDALF code which solves the 1D thermo-hydraulics inside each conductor. The first version of this Thermo-hydraulic EXtended TOol (TEXTO) was developed for producing conservative results and has allowed to simulate the fast discharge of the magnet, providing valuable results such as the mass flow expelled from each pancake. In the second stage, the ANSYS code was configured for modelling the helium transport in the casing and in the winding pack, thus computing more realistic transverse heat fluxes to be injected into the GANDALF code for an accurate calculation of the temperature margin. This second version of TEXTO, which integrates the TACOS (Thermo-hydraulic Ansys COmputation Semi 3D) module, has been used for studying the feasibility of positioning the helium inlets in the electrical connections. The temperature margin has then been found close but below the criterion of 1 K.

  17. The design of hyperthermia hydraulic pump station%高温型液压泵站的设计

    Institute of Scientific and Technical Information of China (English)

    王华安; 武光玉

    2013-01-01

    the article refer to key point of design of hyperthermia hydraulic pump station.This kind of pump station can supply hydraulic oil whose pressure is up to 21 MPa 、quantity of flow is up to 30 L/min when its temperature is120℃ ,and it also can be used as a formal station.%本文介绍了高温型泵站的设计要点。该泵站能够提供温度至120℃、压力至21MPa、流量至30L/min的压力油,亦可作为常规泵站使用。

  18. 78 FR 66941 - Design Considerations for Pivotal Clinical Investigations for Medical Devices; Guidance for...

    Science.gov (United States)

    2013-11-07

    ... for Medical Devices; Guidance for Industry, Clinical Investigators, Institutional Review Boards and... entitled ``Design Considerations for Pivotal Clinical Investigations for Medical Devices.'' This document... premarket submissions for medical devices and for FDA staff who review those submissions. This...

  19. An Analytic Approach to Cascade Control Design for Hydraulic Valve-Cylinder Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Hansen, Anders Hedegaard; Andersen, Torben O.

    2016-01-01

    control and possibly linear active damping functionalities. However difficulties often arise due to the inherent and strong nonlinear nature of hydraulic drives, with the more dominant being nonlinear valve flow- and oil stiffness characteristics, and furthermore the volume expansion/retraction when...

  20. Lunar Module ECS (Environmental Control System) - Design Considerations and Failure Modes. Part 1

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    Design considerations and failure modes for the Lunar Module (LM) Environmental Control System (ECS) are described. An overview of the the oxygen supply and cabin pressurization, atmosphere revitalization, water management and heat transport systems are provided. Design considerations including reliability, flight instrumentation, modularization and the change to the use of batteries instead of fuel cells are discussed. A summary is provided for the LM ECS general testing regime.

  1. Particulate Matter Filtration Design Considerations for Crewed Spacecraft Life Support Systems

    Science.gov (United States)

    Agui, Juan H.; Vijayakumar, R.; Perry, Jay L.

    2016-01-01

    Particulate matter filtration is a key component of crewed spacecraft cabin ventilation and life support system (LSS) architectures. The basic particulate matter filtration functional requirements as they relate to an exploration vehicle LSS architecture are presented. Particulate matter filtration concepts are reviewed and design considerations are discussed. A concept for a particulate matter filtration architecture suitable for exploration missions is presented. The conceptual architecture considers the results from developmental work and incorporates best practice design considerations.

  2. A new type of dehydration unit of natural gas and its design considerations

    Institute of Scientific and Technical Information of China (English)

    LIU Hengwei; LIU Zhongliang; ZHANG Jian; GU Keyu; YAN Tingmin

    2005-01-01

    A new type of dehydration unit for natural gas is described and its basic structure and working principles are presented.The key factors affecting the performance and dehydration efficiency of the unit such as nucleation rate, droplet growth rate, the strength of the swirl, and the position at which the shock wave occurs are discussed. And accordingly the design considerations of each component of the unit are provided. Experimental investigations on the working performance of the unit justified the design considerations.

  3. Hydraulic System Design of 4 YX-4 Type Full-hydraulic Self-propelled Corn Harvester%4 YX-4型全液压自走式玉米收获机液压系统设计

    Institute of Scientific and Technical Information of China (English)

    张志起; 崔中凯; 刘继元; 邸志峰; 魏训成; 姜伟; 周进

    2015-01-01

    随着现代农机技术的进步,液压技术在玉米收获机中的应用越来越广泛。为此,设计了4 YX-4型全液压自走式玉米收获机的液压系统,对液压系统的工作原理、液压元件选择和特点等进行了论述。试验结果表明:该液压系统设计合理、选型正确、可靠性高,能很好完成玉米收获机的工作要求。%With the advancement of modern agricultural technology , the applying of hydraulic technology in corn harvester is getting more and more widely .This article designs the hydraulic system of 4YX-4 type full-hydraulic self-propelled corn harvester and summarizes the principle , characteristic and hydraulic elements selection of this system .The experiment results show that the design is reasonable with correct hydraulic elements selection and high reliability .This system can meet the work requirement of corn harvester well .

  4. Comparison of hydraulic and hemolytic properties of different impeller designs of an implantable rotary blood pump by computational fluid dynamics.

    Science.gov (United States)

    Arvand, Arash; Hahn, Nicole; Hormes, Marcus; Akdis, Mustafa; Martin, Michael; Reul, Helmut

    2004-10-01

    A mixed-flow blood pump for long-term applications has been developed at the Helmholtz-Institute in Aachen, Germany. Central features of this implantable pump are a centrally integrated motor, a blood-immersed mechanical bearing, magnetic coupling of the impeller, and a shrouded impeller, which allows a relatively wide clearance. The aim of the study was a numerical analysis of hydraulic and hemolytic properties of different impeller design configurations. In vitro testing and numerical simulation techniques (computational fluid dynamics [CFD]) were applied to achieve a comprehensive overview. Pressure-flow charts were experimentally measured in a mock loop in order to validate the CFD data. In vitro hemolysis tests were performed at the main operating point of each impeller design. General flow patterns, pressure-flow charts, secondary flow rates, torque, and axial forces on the impeller were calculated by means of CFD. Furthermore, based on streak line techniques, shear stress (stress loading), exposure times, and volume percentage with critical stress loading have been determined. Comparison of CFD data with pressure head measurements showed excel-lent agreement. Also, impressive trend conformity was observed between in-vitro hemolysis results and numerical data. Comparison of design variations yielded clear trends and results. Design C revealed the best hydraulic and hemolytic properties and was chosen as the final design for the mixed-flow rotary blood pump.

  5. A maximum likelihood estimator for bedrock fracture transmissivities and its application to the analysis and design of borehole hydraulic tests

    Science.gov (United States)

    West, Anthony C. F.; Novakowski, Kent S.; Gazor, Saeed

    2006-06-01

    We propose a new method to estimate the transmissivities of bedrock fractures from transmissivities measured in intervals of fixed length along a borehole. We define the scale of a fracture set by the inverse of the density of the Poisson point process assumed to represent their locations along the borehole wall, and we assume a lognormal distribution for their transmissivities. The parameters of the latter distribution are estimated by maximizing the likelihood of a left-censored subset of the data where the degree of censorship depends on the scale of the considered fracture set. We applied the method to sets of interval transmissivities simulated by summing random fracture transmissivities drawn from a specified population. We found the estimated distributions compared well to the transmissivity distributions of similarly scaled subsets of the most transmissive fractures from among the specified population. Estimation accuracy was most sensitive to the variance in the transmissivities of the fracture population. Using the proposed method, we estimated the transmissivities of fractures at increasing scale from hydraulic test data collected at a fixed scale in Smithville, Ontario, Canada. This is an important advancement since the resultant curves of transmissivity parameters versus fracture set scale would only previously have been obtainable from hydraulic tests conducted with increasing test interval length and with degrading equipment precision. Finally, on the basis of the properties of the proposed method, we propose guidelines for the design of fixed interval length hydraulic testing programs that require minimal prior knowledge of the rock.

  6. Single incision Hydraulic Shear Design%单层下切式液压切头剪设计

    Institute of Scientific and Technical Information of China (English)

    王雨

    2013-01-01

    剪切机是用于剪断金属材料的一种机械设备。在板带车间轧制线及其辅助作业线上,一般都配备有各种型式的剪切机,其中大多数是斜刀刃剪切机。近年来,随着液压传动的广泛应用,在现代化连轧板带车间里,愈来愈多地采用液压驱动的剪切机。本文较为全面地介绍了用于电工钢退火机组的液压单层剪在板带处理线上的运用情况,并且叙述了其结构选择与设计计算。%The shearing machine is used to cut metal material a mechanical device. Workshop in strip rolling line and auxiliary jobs online, generally are equipped with all types of shearing machines, most of which is inclined blade shears. In recent years, with the extensive application of hydraulic transmission, in the modern strip rolling workshop, more and more driven by hydraulic shears. This more comprehensive introduction to electrical steel annealing line for hydraulic shear layer in strip processing line use case, and describe its structure selection and design calculations.

  7. 一种用于液体静压导轨的高精密液压站设计%Design of the Ultra-precision Hydraulic Station for Hydraulic Static Pressured Guide

    Institute of Scientific and Technical Information of China (English)

    赵午云; 郭勇

    2014-01-01

    Hydraulic static pressured guide is the important function unit of precision machine tool. Hydraulic station is indispen-sable and supplementary unit for hydraulic static pressured guide in normal operation,and must provide hydraulic static pressured guide with lubricating oil of invariable pressure. An ultra-precision hydraulic station for hydraulic static pressured guide was designed. In this hydraulic station,lubricating oil was provided by precision gear pump driven by variable frequency motor,and pressure export was ensured to be steady by full-closed loop feedback control. The export pressure precision of the hydraulic station can reach ± 0.05%. Good effect is gained in the application of the hydraulic station on the hydraulic static pressured guide of ultra-precision machine tool.%液体静压导轨是精密超精密加工机床的重要功能单元,液压站是液体静压导轨正常工作的必要辅助单元。液体静压导轨要保持高的精度,液压站必须能够为静压导轨提供压力非常稳定的润滑油输入。设计一种用于液体静压导轨的高精密液压站,该液压站利用变频电机驱动精密齿轮泵供给润滑油,利用全闭环反馈调节装置控制润滑油的稳压输出。实际测量证明:该液压站的输出压力稳定精度可达±0.05%,应用于超精密机床上的液体静压导轨取得了良好的效果。

  8. Numerical Modeling of a Thermal-Hydraulic Loop and Test Section Design for Heat Transfer Studies in Supercritical Fluids

    Science.gov (United States)

    McGuire, Daniel

    A numerical tool for the simulation of the thermal dynamics of pipe networks with heat transfer has been developed with the novel capability of modeling supercritical fluids. The tool was developed to support the design and deployment of two thermal-hydraulic loops at Carleton University for the purpose of heat transfer studies in supercritical and near-critical fluids. First, the system was characterized based on its defining features; the characteristic length of the flow path is orders of magnitude larger than the other characteristic lengths that define the system's geometry; the behaviour of the working fluid in the supercritical thermodynamic state. An analysis of the transient thermal behaviour of the model's domains is then performed to determine the accuracy and range of validity of the modeling approach for simulating the transient thermal behaviour of a thermal-hydraulic loop. Preliminary designs of three test section geometries, for the purpose of heat transfer studies, are presented in support of the overall design of the Carleton supercritical thermal-hydraulic loops. A 7-rod-bundle, annular and tubular geometries are developed with support from the new numerical tool. Materials capable of meeting the experimental requirements while operating in supercritical water are determined. The necessary geometries to satisfy the experimental goals are then developed based on the material characteristics and predicted heat transfer behaviour from previous simulation results. An initial safety analysis is performed on the test section designs, where they are evaluated against the ASME Boiler, Pressure Vessel, and Pressure Piping Code standard, required for safe operation and certification.

  9. Design and evaluation of hydraulic baffled-channel PAC contactor for taste and odor removal from drinking water supplies.

    Science.gov (United States)

    Kim, Young-Il; Bae, Byung-Uk

    2007-05-01

    Based on the concept of hydraulic flocculator, a baffled-channel powdered activated carbon (PAC) contactor, placed before the rapid-mixing basin, was designed and evaluated for removal of taste and odor (T&O) in drinking water. PAC adsorption kinetic tests for raw water samples were conducted for selection of design parameters related to contact time and degree of mixing. Within the tested range of velocity gradient (G) from 18 to 83s(-1), mixing had a relatively minor effect on the adsorption kinetics of the PAC. The hydrodynamic characteristics of the pilot-scale horizontally and vertically baffled-channel PAC contactor were investigated by tracer tests. It was found that the plug flow fractions of vertically baffled-channel PAC contactor (vBPC) were higher than those of the horizontally baffled-channel PAC contactor (hBPC) for the same bend width or bend height. However, the hBPC seems to be more appropriate than the vBPC in terms of construction and maintenance. The geosmin and MIB removal rate increased with the number of baffles, PAC dose and contact time increased regardless of bend width in the pilot-scale hBPC. The pair of full-scale hBPCs at Pohang water treatment plant, having a design capacity of 6.5x10(4)m(3)/d with 20min of hydraulic retention time with a safety factor of 2, was designed based on lab- and pilot-scale experimental results. Under a velocity gradient of 20s(-1), the number of baffles to be installed was calculated to be 20 with a space of about 2m between each baffle, resulting in a hydraulic head loss through the contactor of about 0.056m. The successful application of hBPC for T&O removal from drinking water supplies should provide momentum for developing more effective treatment methods.

  10. Design optimization of axial flow hydraulic turbine runner: Part I - an improved Q3D inverse method

    Science.gov (United States)

    Peng, Guoyi; Cao, Shuliang; Ishizuka, Masaru; Hayama, Shinji

    2002-06-01

    With the aim of constructing a comprehensive design optimization procedure of axial flow hydraulic turbine, an improved quasi-three-dimensional inverse method has been proposed from the viewpoint of system and a set of rotational flow governing equations as well as a blade geometry design equation has been derived. The computation domain is firstly taken from the inlet of guide vane to the far outlet of runner blade in the inverse method and flows in different regions are solved simultaneously. So the influence of wicket gate parameters on the runner blade design can be considered and the difficulty to define the flow condition at the runner blade inlet is surmounted. As a pre-computation of initial blade design on S2m surface is newly adopted, the iteration of S1 and S2m surfaces has been reduced greatly and the convergence of inverse computation has been improved. The present model has been applied to the inverse computation of a Kaplan turbine runner. Experimental results and the direct flow analysis have proved the validation of inverse computation. Numerical investigations show that a proper enlargement of guide vane distribution diameter is advantageous to improve the performance of axial hydraulic turbine runner. Copyright

  11. NUMERICAL MODELING OF MULTICYLINDER ELECTRO-HYDRAULIC SYSTEM AND CONTROLLER DESIGN FOR SHOCK TEST MACHINE

    Institute of Scientific and Technical Information of China (English)

    CHU Deying; ZHANG Zhiyi; WANG Gongxian; HUA Hongxing

    2007-01-01

    A high fidelity dynamic model of a high-energy hydraulically-actuated shock test machine for heavy weight devices is presented to satisfy the newly-built shock resistance standard and simulate the actual underwater explosion environments in laboratory as well as increase the testing capability of shock test machine. In order to produce the required negative shock pulse in the given time duration, four hydraulic actuators are utilized. The model is then used to formulate an advanced feedforward controller for the system to produce the required negative waveform and to address the motion synchronization of the four cylinders. The model provides a safe and easily controllable way to perform a "virtual testing" before starting potentially destructive tests on specimen and to predict performance of the system. Simulation results have demonstrated the effectiveness of the controller.

  12. Parameter Design for the Energy-Regeneration System of Series Hydraulic-Hybrid Bus

    Directory of Open Access Journals (Sweden)

    SONG Yunpu

    2012-10-01

    Full Text Available This paper simplifies the energy recovery process in the series hydraulic hybrid bus’ energy regeneration system into a process in which the main axle’s moment of inertia drives the secondary element variable delivery pump/motor and brings hydraulic oil from the oil tank to the accumulator. This process enables braking of the vehicle and also allows recovery of energy to the accumulator. Based on the flow equation for the secondary element variable delivery pump/motor and the torque equilibrium equation for its axle, the force equilibrium equation for vehicle braking and the pressure variation and flow continuity equations for the accumulator, simulation studies are conducted to analyze the effects of various system parameters, such as accumulator capacity, displacement of the secondary element variable delivery pump/motor, initial operating pressure of the system, etc. on system performance during regenerative braking.  

  13. 基于AMESim液压元件设计库的液压系统建模与仿真研究%Modeling and Simulation Research of Hydraulic System Based on Hydraulic Component Design Library of AMESim

    Institute of Scientific and Technical Information of China (English)

    张宪宇; 陈小虎; 何庆飞; 万俊盛

    2012-01-01

    A hydraulic system test-bed was taken as research object, and AMESim was used for simulation analysis. Hie HCD simulation model of the hydraulic system was built. In order to verify the correctness of the model, characteristics simulation was proceeded and compared with physical characteristics. The HCD simulation model was used to analyze the characteristic factors which in- flueneed hydraulic actuator velocity. The quantification contrast curves of hydraulic actuator velocity were gotten, which were influenced by flow, piston diameter, piston rod diameter and leakage. It provides basis for hydraulic system design and fault diagnosis.%以某液压实验台为研究对象,运用AMESim对液压系统进行仿真分析.建立液压系统的HCD仿真模型;进行特性仿真,并与物理特性进行对比,验证了HCD仿真模型的正确性;运用所建立的HCD仿真模型对影响液压缸运动速度的因素进行分析,给出不同的流量、活塞缸直径、活塞杆直径及泄漏影响液压缸运动速度的量化对比曲线,从而为液压系统的设计及故障诊断提供依据.

  14. Issues Related To Troubleshooting Of Avionic Hydraulic Units

    Directory of Open Access Journals (Sweden)

    Jastrzębski Grzegorz

    2014-12-01

    Full Text Available The paper outlines workflows associated with troubleshooting of avionic hydraulic systems with detailed description of the troubleshooting algorithm and classification of diagnostic signals provided by avionic hydraulic systems and their subassemblies. Attention is paid to measurement sequences for diagnostic signals from hydraulic systems, circuits and units. Detailed description is dedicated to an innovative design of a troubleshooting device intended for direct measurements of internal leaks from avionic hydraulic units. Advantages of the proposed measurement method are summarized with benefits from use of the presented device and compared against the methods that are currently in use. Subsequent phases of the troubleshooting process are described with examples of measurement results that have been acquired from subassemblies of hydraulic systems of SU-22 aircrafts currently in service at Polish Air Forces with consideration given to cases when the permissible threshold of diagnostic signals were exceeded. Finally, all results from investigations are subjected to thorough analysis.

  15. Design of Hydraulic Protection Equipment Served the Disabled Weight-lifting%残疾人举重液压伺服保护装置设计

    Institute of Scientific and Technical Information of China (English)

    汪功明

    2015-01-01

    A kind of hydraulic protection equipment served the disabled weight⁃lifting was designed. The equipment consisted of guide rail, hydraulic following unit and hydraulic lifting unit. It mainly depended on hydraulic servo theory to work. The technical pro⁃posal and the model designs of the core structure of the equipment were stated.%设计一种残疾人举重保护装置,该装置由导轨、液压跟随单元、液压托举单元等三部分组成,主要依据液压伺服原理工作。阐述了该装置的技术方案,并对装置的核心结构做了选型设计。

  16. Design of Electric-hydraulic Control Butterfly Valve%电液动调节蝶阀的设计

    Institute of Scientific and Technical Information of China (English)

    王建新; 张逸芳

    2014-01-01

    Introduced process design、main content and key factors to consider of the electro-hydraulic control valve ,Discusses the points for attention and suggestions of valve body,actuator,control system design and calculation.%介绍了电液动调节蝶阀方案设计的过程、主要内容及考虑的关键因素,论述了阀门本体、执行机构、控制系统等设计计算的关注点及建议。

  17. 船用多液动蝶阀启闭液压控制系统的设计%Design on Hydraulic Control System for Marine Muliti-hydraulic Butterfly Valve On-off

    Institute of Scientific and Technical Information of China (English)

    于娜; 杨志贤; 毛卫平; 顾寄南

    2016-01-01

    A hydraulic system to realize the marine butterfly valve open-shut and opening was designed, and the project of the hy-draulic control system was made. Combining with the actual working condition of the system, the selection and parameter of the main components of the hydraulic system were analyzed and calculated. Considering the working feature of the hydraulic control system for marine butterfly valve, the hydraulic power unit was designed in automatic unloading mode and the accumulator was added to supply hydraulic oil assistantly in order to ensure the pressure maintain within the allowable scope of the work, and the safe and stable opera-tion of the whole system are ensured.%设计了一种船用蝶阀启、 闭液压控制系统,确定了该液压系统的控制方案;结合该系统的实际工况要求,对该系统中各主要元件的选型和参数进行了分析和计算;结合船用蝶阀液压遥控系统的工作特点,对液压泵站进行了设计,设置两台液压泵互为备用,并增加蓄能器辅助供油,同时泵站采用自动卸荷方式,保证系统油压维持在允许的工作范围内,从而确保了整个船用阀门液压遥控系统的的安全稳定运行.

  18. Design of Spinning Forming Hydraulic Press's Hydraulics and Control System%旋压成形液压机液压系统及控制系统的设计

    Institute of Scientific and Technical Information of China (English)

    李卫民; 丛树阳

    2011-01-01

    After careful analyzing the work of the hydrostatic press,the design project was determined,hydraulic schematic diagram of hydraulic spinning press was formulated,and pupm stations of the hydraulic system was designed.Using CAD technology designed integrated valves of the hydraulic system.The control system was based on the movement sequence of hydraulic system and the principle of automatic control.Through using the PLC and touch screen joint programming,PLC program development simulation software,the use of man-machine interface configuration software for configuration and programming and PLC and human-machine interface technology of communication,the key issuse of determining and selection of components and technical parameters in hydraulic system of the hydraulic spinning machine have been solved,as well as to the design of automatic control procedures and the control procedures and the control design of man-machine interface.%通过对旋压液压机的工况的分析,确定了设计方案,制定了完成旋压加工的旋压液压机液压原理图,设计了液压系统的液压泵站,采用CAD技术设计了集成式液压系统的集成块阀组;其控制系统是以液压系统的动作顺序和自动控制原理为基础,采用PLC和触摸屏联合编程技术、PLC程序开发软件编程模拟、人机界面运用组态软件进行组态和编程、PLC和人机界面的通讯等技术,解决了旋压液压机液压系统中各部件技术参数的确定与选用、自动控制程序的设计、人机界面的控制设计等关键问题.

  19. Vorticity and turbulence effects in fluid structure interaction an application to hydraulic structure design

    CERN Document Server

    Brocchini, M

    2006-01-01

    This book contains a collection of 11 research and review papers devoted to the topic of fluid-structure interaction.The subject matter is divided into chapters covering a wide spectrum of recognized areas of research, such as: wall bounded turbulence; quasi 2-D turbulence; canopy turbulence; large eddy simulation; lake hydrodynamics; hydraulic hysteresis; liquid impacts; flow induced vibrations; sloshing flows; transient pipe flow and air entrainment in dropshaft.The purpose of each chapter is to summarize the main results obtained by the individual research unit through a year-long activity

  20. Design, analysis and control of hydraulic soft yaw system for 5MW wind turbine

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2012-01-01

    by active control of a hydraulic yaw system. The control is based on a non-linear and linear model derived based on a concept yaw system for the NREL 5MW wind turbine. The control strategies show a reduction in pressure pulsations under load and it is concluded that the strategie including high......As wind turbines increase in size and the demands for lifetime also increases, new methods of load reduction needs to be examined. One method is to make the yaw system of the turbine soft/flexible and wereby dampen the loads to the system. This paper presents work done on dampening of these loads...

  1. Numerical models in hydraulic design; Numerische Modelle bei der wasserbaulichen Planung

    Energy Technology Data Exchange (ETDEWEB)

    Musall, M.; Stelzer, C.; Nestmann, F. [Technische Univ. Karlsruhe (DE). Inst. fuer Wasser und Gewaesserentwicklung (IWG); Theobald, S. [Technische Univ. Karlsruhe (DE). Inst. fuer Wasser und Gewaesserentwicklung (IWG); Kassel Univ. (Germany)

    2006-07-01

    By means of a practical example the significance of numerical modelling within a hybrid hydraulic planning process, which is based on the combination of several numerical and physical models, is shown. Thereby especially the interaction of the different applied numerical methods as well as the possibilities of numerical optimization of preliminary planning aiming on reduced construction costs of the laboratory models are pointed out. A detailed description of the additional laboratory models and their techniques is given by the article of Queisser et al. (orig.)

  2. Evolution of design considerations in complex craniofacial reconstruction using patient-specific implants.

    Science.gov (United States)

    Peel, Sean; Bhatia, Satyajeet; Eggbeer, Dominic; Morris, Daniel S; Hayhurst, Caroline

    2017-06-01

    Previously published evidence has established major clinical benefits from using computer-aided design, computer-aided manufacturing, and additive manufacturing to produce patient-specific devices. These include cutting guides, drilling guides, positioning guides, and implants. However, custom devices produced using these methods are still not in routine use, particularly by the UK National Health Service. Oft-cited reasons for this slow uptake include the following: a higher up-front cost than conventionally fabricated devices, material-choice uncertainty, and a lack of long-term follow-up due to their relatively recent introduction. This article identifies a further gap in current knowledge - that of design rules, or key specification considerations for complex computer-aided design/computer-aided manufacturing/additive manufacturing devices. This research begins to address the gap by combining a detailed review of the literature with first-hand experience of interdisciplinary collaboration on five craniofacial patient case studies. In each patient case, bony lesions in the orbito-temporal region were segmented, excised, and reconstructed in the virtual environment. Three cases translated these digital plans into theatre via polymer surgical guides. Four cases utilised additive manufacturing to fabricate titanium implants. One implant was machined from polyether ether ketone. From the literature, articles with relevant abstracts were analysed to extract design considerations. In all, 19 frequently recurring design considerations were extracted from previous publications. Nine new design considerations were extracted from the case studies - on the basis of subjective clinical evaluation. These were synthesised to produce a design considerations framework to assist clinicians with prescribing and design engineers with modelling. Promising avenues for further research are proposed.

  3. Nonlinear dynamic analysis and robust controller design for Francis hydraulic turbine regulating system with a straight-tube surge tank

    Science.gov (United States)

    Liang, Ji; Yuan, Xiaohui; Yuan, Yanbin; Chen, Zhihuan; Li, Yuanzheng

    2017-02-01

    The safety and stability of hydraulic turbine regulating system (HTRS) in hydropower plants become increasingly important since the rapid development and the broad application of hydro energy technology. In this paper, a novel mathematical model of Francis hydraulic turbine regulating system with a straight-tube surge tank based on a few state-space equations is introduced to study the dynamic behaviors of the HTRS system, where the existence of possible unstable oscillations of this model is studied extensively and presented in the forms of the bifurcation diagram, time waveform plot, phase trajectories, and power spectrum. To eliminate these undesirable behaviors, a specified fuzzy sliding mode controller is designed. In this hybrid controller, the sliding mode control law makes full use of the proposed model to guarantee the robust control in the presence of system uncertainties, while the fuzzy system is applied to approximate the proper gains of the switching control in sliding mode technique to reduce the chattering effect, and particle swarm optimization is developed to search the optimal gains of the controller. Numerical simulations are presented to verify the effectiveness of the designed controller, and the results show that the performances of the nonlinear HTRS system assisted with the proposed controller is much better than that with the commonly used optimal PID controller.

  4. 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...

  5. Integrated Hydraulic Power Unit Design for Marine Hydraulic Hauling Winch%船用拖拉液压绞车用集成式液压泵站的设计

    Institute of Scientific and Technical Information of China (English)

    严建新; 王元杰

    2014-01-01

    采用液压泵站与执行元件(船用液压拖拉绞车)集成一体的设计,较传统液压系统中的液压泵站与执行元件分离的设计而言,操作时既方便了对整个液压系统相关数据的观察,又能准确地观测到执行元件的运行情况;同时为整体运输带来了方便,无需运输后再整体接管装配的过程,可直接进行生产运作;在检测运行和维修方面也有很大的便捷。用户应用结果表明,该设计安全可靠,结构紧凑,工作效率高,运输操作便捷,可以大范围内推广应用。%This design integrated the hydraulic power unit with the implemented components (marine hydraulic haul-ing winch), compared to the traditional hydraulic power unit with the separation of implemented components in com-mon hydraulic system, the operation is convenient to observe the related technical data of hydraulic system, and can accurately observed operation performance. At the same time, it's convenient to whole packing and transportation. It can directly put into action without any more connection of pipeline and coupling. And it's very convenient in the op-eration and maintenance and repair. The applied result from the customers indicates that this design is safety, com-pact layout design as whole, high work efficiency, and convenient to transport, can be widely used in various field.

  6. 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...

  7. 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...

  8. Design and Optimization of the Slide Guide System of Hydraulic Press Based on Energy Loss Analysis

    Directory of Open Access Journals (Sweden)

    Mengdi Gao

    2016-06-01

    Full Text Available The clearances in the slide guide system of a hydraulic press are one of the significant factors affecting its accuracy. These clearances also affect the energy consumption of the press. An energy loss model that considers the oil leaks and friction associated with these clearances was proposed, and the size of clearances was optimized based on the model. The maximum allowable eccentric load and the energy loss on the wedge clearance condition were calculated to ensure the slide and guide pillars function properly. The stiffness of pillars and wear of guide rails were checked under an eccentric load condition. A case for rapid sheet metal forming with a 20 MN hydraulic press was examined. For this case, the optimum fit clearances were found to be approximately 0.4 mm. The energy loss under an eccentric load condition was increased by approximately 83% compared to a non-eccentric load condition. The pillars were optimized by reducing excessive stiffness, which served to decrease the pillar weight by nearly 20%.

  9. Design considerations and experimental observations for the TAMU air-cooled reactor cavity cooling system for the VHTR

    Science.gov (United States)

    Sulaiman, S. A.; Dominguez-Ontiveros, E. E.; Alhashimi, T.; Budd, J. L.; Matos, M. D.; Hassan, Y. A.

    2015-04-01

    The Reactor Cavity Cooling System (RCCS) is a promising passive decay heat removal system for the Very High Temperature Reactor (VHTR) to ensure reliability of the transfer of the core residual and decay heat to the environment under all off-normal circumstances. A small scale experimental test facility was constructed at Texas A&M University (TAMU) to study pertinent multifaceted thermal hydraulic phenomena in the air-cooled reactor cavity cooling system (RCCS) design based on the General Atomics (GA) concept for the Modular High Temperature Gas-Cooled Reactor (MHTGR). The TAMU Air-Cooled Experimental Test Facility is ⅛ scale from the proposed GA-MHTGR design. Groundwork for experimental investigations focusing into the complex turbulence mixing flow behavior inside the upper plenum is currently underway. The following paper illustrates some of the chief design considerations used in construction of the experimental test facility, complete with an outline of the planned instrumentation and data acquisition methods. Computational Fluid Dynamics (CFD) simulations were carried out to furnish some insights on the overall behavior of the air flow in the system. CFD simulations assisted the placement of the flow measurement sensors location. Preliminary experimental observations of experiments at 120oC inlet temperature suggested the presence of flow reversal for cases involving single active riser at both 5 m/s and 2.25 m/s, respectively and four active risers at 2.25 m/s. Flow reversal may lead to thermal stratification inside the upper plenum by means of steady state temperature measurements. A Particle Image Velocimetry (PIV) experiment was carried out to furnish some insight on flow patterns and directions.

  10. Design considerations and experimental observations for the TAMU air-cooled reactor cavity cooling system for the VHTR

    Energy Technology Data Exchange (ETDEWEB)

    Sulaiman, S. A., E-mail: shamsulamri@tamu.edu; Dominguez-Ontiveros, E. E., E-mail: elvisdom@tamu.edu; Alhashimi, T., E-mail: jbudd123@tamu.edu; Budd, J. L., E-mail: dubaiboy@tamu.edu; Matos, M. D., E-mail: mailgoeshere@gmail.com; Hassan, Y. A., E-mail: yhasssan@tamu.edu [Department of Nuclear Engineering, Texas A and M University, College Station, TX, 77843-3133 (United States)

    2015-04-29

    The Reactor Cavity Cooling System (RCCS) is a promising passive decay heat removal system for the Very High Temperature Reactor (VHTR) to ensure reliability of the transfer of the core residual and decay heat to the environment under all off-normal circumstances. A small scale experimental test facility was constructed at Texas A and M University (TAMU) to study pertinent multifaceted thermal hydraulic phenomena in the air-cooled reactor cavity cooling system (RCCS) design based on the General Atomics (GA) concept for the Modular High Temperature Gas-Cooled Reactor (MHTGR). The TAMU Air-Cooled Experimental Test Facility is ⅛ scale from the proposed GA-MHTGR design. Groundwork for experimental investigations focusing into the complex turbulence mixing flow behavior inside the upper plenum is currently underway. The following paper illustrates some of the chief design considerations used in construction of the experimental test facility, complete with an outline of the planned instrumentation and data acquisition methods. Computational Fluid Dynamics (CFD) simulations were carried out to furnish some insights on the overall behavior of the air flow in the system. CFD simulations assisted the placement of the flow measurement sensors location. Preliminary experimental observations of experiments at 120oC inlet temperature suggested the presence of flow reversal for cases involving single active riser at both 5 m/s and 2.25 m/s, respectively and four active risers at 2.25 m/s. Flow reversal may lead to thermal stratification inside the upper plenum by means of steady state temperature measurements. A Particle Image Velocimetry (PIV) experiment was carried out to furnish some insight on flow patterns and directions.

  11. Design and verification of additional filtration for the application of ecological transmission and hydraulic fluids in tractorc

    Directory of Open Access Journals (Sweden)

    Pavel Máchal

    2013-01-01

    Full Text Available This contribution presents the design and function verification of additional filtration. It is intended for the common transmission and hydraulic oil filling of tractors. The main role of this filtration concept is to ensure a high level of oil cleanness as a condition for the application of ecologic fluids in tractors. The next one is to decrease the wear of lubricated tractor components, the degradation of oil and eventually to extend the interval of oil change. The designed additional filtering is characterized by ease installation through the use of quick couplings and hoses to the external hydraulic circuit. Therefore, the filtration is suitable for various tractor types. Filter element has been designed with the filter ability 1micron and the ability to separate to 0.5 dm3 of water from oil. Function of additional filtration was verified during the 150 engine hours of tractor operation. During this time period the oil contamination was evaluated on the basis of chemical elements content such as Fe, Cu, Si, Al, Ni, Mo and Cr. The additive concentration was evaluated on the basis of chemical elements content such as Ca, P and Zn. During the test operation of tractor the concentration decrease of chemical elements reached the values 25.53 % (Fe, 23.53 % (Si, 25 % (Al and 5.5 % (Cu. The decrease of additive concentration reached only medium level (6.6 %. Therefore, the designed additional filtration doesn’t remove additives from oil. Based on the evaluation of the content of chemical elements (that representing contamination and additives, we can say that the designed filtering method is suitable for use in agricultural tractors.

  12. Design and Simulation of Hydraulic System of Press Machine%压力机液压系统的设计与仿真

    Institute of Scientific and Technical Information of China (English)

    宋晓美; 韩亮

    2014-01-01

    For the problems of the vibration and noise common to hydraulic system of press,the hydraulic and control system applied in the actual production is designed.The principle of the hydraulic system is analyzed and the hydraulic circuit and electric control circuit of the system is simulated by FluidSIM software.%针对压力机液压系统常见的振动及噪声问题,设计了应用于生产实际的压力机液压及控制系统,分析了液压系统原理,并利用FluidSIM软件对该系统的液压回路及电气控制回路进行仿真。

  13. Design and Construction of Experiment for Direct Electron Irradiation of Uranyl Sulfate Solution: Bubble Formation and Thermal Hydraulics Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakho [Argonne National Lab. (ANL), Argonne, IL (United States); Heltemes, Thad [Argonne National Lab. (ANL), Argonne, IL (United States); Sun, Zaijing [Argonne National Lab. (ANL), Argonne, IL (United States); Wardle, Kent E. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, James [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, Dominique [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-10-01

    Argonne is assisting SHINE Medical Technologies in developing SHINE, a system for producing fission-product 99Mo using a D/T-accelerator to produce fission in a non-critical target solution of aqueous uranyl sulfate. We have developed an experimental setup for studying thermal-hydraulics and bubble formation in the uranyl sulfate solution to simulate conditions expected in the SHINE target solution during irradiation. A direct electron beam from the linac accelerator will be used to irradiate a 20 L solution (sector of the solution vessel). Because the solution will undergo radiolytic decomposition, we will be able to study bubble formation and dynamics and effects of convection and temperature on bubble behavior. These experiments will serve as a verification/ validation tool for the thermal-hydraulic model. Utilization of the direct electron beam for irradiation allows homogeneous heating of a large solution volume and simplifies observation of the bubble dynamics simultaneously with thermal-hydraulic data collection, which will complement data collected during operation of the miniSHINE experiment. Irradiation will be conducted using a 30-40 MeV electron beam from the high-power linac accelerator. The total electron-beam power will be 20 kW, which will yield a power density on the order of 1 kW/L. The solution volume will be cooled on the front and back surfaces and central tube to mimic the geometry of the proposed SHINE solution vessel. Also, multiple thermocouples will be inserted into the solution vessel to map thermal profiles. The experimental design is now complete, and installation and testing are in progress.

  14. 某隧道液压台车设计%Design of Hydraulic Trolley for a Certain Tunnel

    Institute of Scientific and Technical Information of China (English)

    王春梅; 徐涛; 周仕强

    2011-01-01

    Considering the geological conditions ot a certain tunnel, a tull-face steel formwork concrete liner tunnel trolley was designed.The constitution of the steel trolley was described.The mechanical, hydraulic, electrical system of the trolley were designed, while load analysis of trolley was made.The practical results show that this trolley meets the construction demand of the tunnel.%针对某隧道的地质状况,设计全断面钢模板砼衬砌隧道台车.详细介绍钢模台车的组成,对台车的机电液系统进行设计,同时对台车进行受力分析.使用结果表明设计的钢模台车满足该隧道的施工要求.

  15. Design considerations for post accident monitoring system of a research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Gwi Sook; Park, Je Yun; Kim, Young Ki [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    The Post Accident Monitoring System (PAMS) provides primary information for operators to assess the plant conditions and perform their role in bringing the plant to a safe condition during an accident. The PAMS of NPP (Nuclear Power Plant) in KOREA provides the continuous display of the PAM category 1 parameters specified in R.G 1.97, Rev. 03. Recently the PAMS of NPP has been designed according to R.G 1.97, Rev. 04. There is no PAMS at the HANARO in KOREA, but recently RRs (Research Reactors) around the world are going to have PAMS for various multi purposes. We should determine the design considerations for PAMS in a Korean RR based on the design state analysis. Thus, this paper proposes strategies on the design considerations for the PAMS of a Korean RR.

  16. Research design considerations for single-dose analgesic clinical trials in acute pain

    DEFF Research Database (Denmark)

    Cooper, Stephen A; Desjardins, Paul J; Turk, Dennis C

    2016-01-01

    This article summarizes the results of a meeting convened by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) on key considerations and best practices governing the design of acute pain clinical trials. We discuss the role of early phase clinical trials......, including pharmacokinetic-pharmacodynamic (PK-PD) trials, and the value of including both placebo and active standards of comparison in acute pain trials. This article focuses on single-dose and short-duration trials with emphasis on the perioperative and study design factors that influence assay...... sensitivity. Recommendations are presented on assessment measures, study designs, and operational factors. Although most of the methodological advances have come from studies of postoperative pain after dental impaction, bunionectomy, and other surgeries, the design considerations discussed are applicable...

  17. Research design considerations for single-dose analgesic clinical trials in acute pain: IMMPACT recommendations.

    Science.gov (United States)

    Cooper, Stephen A; Desjardins, Paul J; Turk, Dennis C; Dworkin, Robert H; Katz, Nathaniel P; Kehlet, Henrik; Ballantyne, Jane C; Burke, Laurie B; Carragee, Eugene; Cowan, Penney; Croll, Scott; Dionne, Raymond A; Farrar, John T; Gilron, Ian; Gordon, Debra B; Iyengar, Smriti; Jay, Gary W; Kalso, Eija A; Kerns, Robert D; McDermott, Michael P; Raja, Srinivasa N; Rappaport, Bob A; Rauschkolb, Christine; Royal, Mike A; Segerdahl, Märta; Stauffer, Joseph W; Todd, Knox H; Vanhove, Geertrui F; Wallace, Mark S; West, Christine; White, Richard E; Wu, Christopher

    2016-02-01

    This article summarizes the results of a meeting convened by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) on key considerations and best practices governing the design of acute pain clinical trials. We discuss the role of early phase clinical trials, including pharmacokinetic-pharmacodynamic (PK-PD) trials, and the value of including both placebo and active standards of comparison in acute pain trials. This article focuses on single-dose and short-duration trials with emphasis on the perioperative and study design factors that influence assay sensitivity. Recommendations are presented on assessment measures, study designs, and operational factors. Although most of the methodological advances have come from studies of postoperative pain after dental impaction, bunionectomy, and other surgeries, the design considerations discussed are applicable to many other acute pain studies conducted in different settings.

  18. Some Considerations Regarding the Design and Implementation of Data Warehouse in Insurance Broker Management

    Directory of Open Access Journals (Sweden)

    Alexandru Manole

    2015-09-01

    Full Text Available This paper describes a proposal for a data warehouse model, designed for the use in the management of insurance brokerage companies. The model aims to provide information to the leadership of such companies, beyond the classical knowledge drawn from current activity reports. Also, the design process took into consideration the characteristics of the business model analysed. The model is then “exploited” by making some analyses on the data loaded.

  19. 77 FR 74195 - Draft Guidance for Industry and Food and Drug Administration Staff; Design Considerations for...

    Science.gov (United States)

    2012-12-13

    ... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry and Food and Drug Administration Staff; Design Considerations for Devices Intended for Home Use; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing...

  20. Designing the Best Urban, Preservice Elementary Science Methods Course: Dilemmas and Considerations

    Science.gov (United States)

    Moscovici, Hedy; Osisioma, Irene

    2008-01-01

    This paper addresses the dilemmas encountered by two secondary science education instructors designing a course for preservice elementary teachers. Taking into consideration past experiences of teaching education and science courses in general and with preservice elementary teachers in particular and recommendations from state and national…

  1. Hydraulic Resistance of Vitreous Cutters: The Impact of Blade Design and Cut Rate

    Science.gov (United States)

    Rossi, Tommaso; Querzoli, Giorgio; Angelini, Giampiero; Malvasi, Carlo; Rossi, Alessandro; Morini, Mario; Esposito, Graziana; Micera, Alessandra; di Luca, Natale Mario; Ripandelli, Guido

    2016-01-01

    Purpose To measure the hydraulic resistance (HR) of vitreous cutters equipped with a Regular guillotine Blade (RB) or double edge blade (DEB) at cut rates comprised between 0 and 12,000 cuts per minute (CPM) and compare it with vitreous fragment size. This was an in vitro experimental study; in vivo HR measure and vitreous sampling. Methods HR, defined as aspiration pressure/flow rate, was measured in balanced salt solution (BSS; Alcon, Fort Worth, TX) (in vitro) and during pars plana vitrectomy of 20 consecutive patients aged 18 to 65, undergoing macular surgery. HR was recorded at increasing cut rates (500–6000 CPM for the RB and 500–12,000 CPM for the DEB; 5 mL/min flow). Vitreous samples were withdrawn and analyzed with Western and collagen type II and IX immunostaining to evaluate protein size. The main outcome measures were hydraulic resistance (mm Hg/ml/min [±SD]) and optic density for Western blot and immunostaining. Results RB and DEB showed identical HR in BSS between 0 and 3000 CPM. Above 3000 CPM, RB HR steadily increased, and was significantly higher than DEB HR. Vitreous HR was also similar for the two blades between 0 and 1500 CPM. Above 1500 CPM, RB offered a significantly higher resistance. Western blot and immunostaining of vitreous samples did not yield a significant difference in size, regardless of blade type and cut rate. Conclusions DEB is more efficient, offering a lower HR than RB over 1500 CPM in human vitreous. There is no viscosity reduction as a function of cut-rate between 1500 and 12,000 CPM, as HR does not vary. Translational Relevance Future vitreous cutters will benefit of a DEB; optimal cut rate needs to be defined, and the simple increase of cut rate does not provide benefits after a certain limit to be assessed. PMID:27441099

  2. Design of a hydraulic microturbine type Michell-Banki; Diseno de una microturbina hidraulica tipo Michell-Banki

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Luiz, Norberto; Rodriguez Bautista, Jose; Verduzco Figueroa, Hilario; Gudino Lau, Jorge; Galindo Granados, Miguel angel [Universidad de Colima, Facultad de Ingenieria Electromecanica, Manzanillo, Colima (Mexico)]. E-mail: norberto_lopez@ucol.mx

    2010-11-15

    The aim of this paper is to present the design of a hydraulic microturbine (MTH), which may be installed in areas where supplies are not available for electric power transmission lines, but possessing hydroelectric. MTH's role is to convert hydraulic energy into mechanical work, is coupled to an electric generator, whose function is to convert the mechanical energy into electrical energy. The turbine generator set will produce more electric power the greater the hydroelectric of the area. In southern Mexico, we have great hydroelectric potential, as the case of the states of Veracruz, Chiapas and Oaxaca, which have small causes of rivers where the MTH could be installed and put into operation. [Spanish] El objetivo de este articulo es presentar el diseno de una microturbina hidraulica (MTH), la cual podra ser instalada en zonas donde no se cuente con suministro de energia electrica por medio de lineas de transmision, pero que posean aprovechamientos hidroelectricos. La funcion de la MTH es convertir la energia hidraulica en trabajo mecanico, estara acoplada a un generador electrico, cuya funcion es convertir dicha energia mecanica en energia electrica. El conjunto turbina generador producira mas potencia electrica mientras mayor sea el aprovechamiento hidroelectrico de la zona. En el sur de Mexico contamos con un gran potencial hidroelectrico, como el caso de los estados de Veracruz, Chiapas y Oaxaca, que cuentan con pequenos causes de rios donde las MTH podrian ser instaladas y puestas en operacion.

  3. 液压泵性能测试实验台设计%Design of Performance Test Bench for Hydraulic Pump

    Institute of Scientific and Technical Information of China (English)

    郑明辉; 江吉彬; 郭熛

    2011-01-01

    Hydraulic pump as hydraulic system's power part, is one of important parts of engineering machinery product. The hydraulic pump performance test bench is the necessary device for hydraulic pump product quality examination which is the main safe guard of pump product quality. A hydraulic pump performance test bench was designed. The composition, working principle and char acteristics of the hydraulic system were introduced. Data test and analysis were carried on.%液压泵作为液压系统的动力元件,是工程机械产品的重要部件之一.液压泵性能测试实验台是进行液压泵产品质量检测的必要设备,是泵产品质量监控的主要保障.设计了液压泵性能测试实验台,介绍液压系统组成、工作原理和特点,并进行了数据测试及分析.

  4. Precision and cost considerations for two-stage sampling in a panelized forest inventory design.

    Science.gov (United States)

    Westfall, James A; Lister, Andrew J; Scott, Charles T

    2016-01-01

    Due to the relatively high cost of measuring sample plots in forest inventories, considerable attention is given to sampling and plot designs during the forest inventory planning phase. A two-stage design can be efficient from a field work perspective as spatially proximate plots are grouped into work zones. A comparison between subsampling with units of unequal size (SUUS) and a simple random sample (SRS) design in a panelized framework assessed the statistical and economic implications of using the SUUS design for a case study in the Northeastern USA. The sampling errors for estimates of forest land area and biomass were approximately 1.5-2.2 times larger with SUUS prior to completion of the inventory cycle. Considerable sampling error reductions were realized by using the zones within a post-stratified sampling paradigm; however, post-stratification of plots in the SRS design always provided smaller sampling errors in comparison. Cost differences between the two designs indicated the SUUS design could reduce the field work expense by 2-7 %. The results also suggest the SUUS design may provide substantial economic advantage for tropical forest inventories, where remote areas, poor access, and lower wages are typically encountered.

  5. Methodologic issues, theoretical considerations, and design criteria for experimental animal and cell culture experiments.

    Science.gov (United States)

    Birt, D F

    1997-12-01

    This article provides background information that is important when evaluating the relevance to humans of particular animal or in vitro experiments designed to assess the relations between fatty acids and cancer. Considerations in designing carcinogenesis studies to assess the relation between dietary fatty acids and human cancer include selection of the animal model and design of the experimental diets. Animal carcinogenesis models are generally best for evaluating the early phases of cancer development: the initiation and promotion of cancer. Transplantation protocols have been developed for evaluating the effect of diet on the growth and metastasis of partially or fully transformed cells. The variables that are important in such models are the origin and biology of the cell line, the animal host used for the implantation, the site of transplantation, whether the primary tumor is excised after a period of time to allow for metastasis, and when the diets are fed relative to the different phases of tumor growth and metastasis. Studies in cultured cells have been particularly useful for assessing the mechanisms by which fatty acids affect cancer. Considerations in designing studies with cultured cells include selection of the cell line, cell culture conditions, selection of biological endpoints that are relevant to human cancer, and in vivo confirmation of the mechanisms observed in vitro. Design considerations for each of these experimental approaches are discussed and the contributions of each approach are summarized.

  6. Design Considerations of Very Low Profile Coupled Inductors for Flexible Photovoltaic Module

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Acanski, M; Popovic, J

    2012-01-01

    important design issues for the sandwich core structure including self-inductance, leakage inductance, eddy current effect and core loss are analyzed in-depth in this work. Since the non-uniform flux is distributed in the core plates, the parameters calculation and the design considerations are completely......Power converters with flexible PCB integrated magnetic components are highly demanded in future photovoltaic (PV) applications, resulting in a higher power density. In this paper, a 1.5-mm thickness integrated coupled inductor with planar sandwich core structure is under investigation. Several...... different with the traditional magnetic approaches. Accordingly, this paper enables original design considerations as a guideline for sandwiched coupled inductor. In order to reduce the high frequency eddy current effect in sandwich core structure, section III initiates a discussion with adjustable core...

  7. Web-based assessments of physical activity in youth: considerations for design and scale calibration.

    Science.gov (United States)

    Saint-Maurice, Pedro F; Welk, Gregory J

    2014-12-01

    This paper describes the design and methods involved in calibrating a Web-based self-report instrument to estimate physical activity behavior. The limitations of self-report measures are well known, but calibration methods enable the reported information to be equated to estimates obtained from objective data. This paper summarizes design considerations for effective development and calibration of physical activity self-report measures. Each of the design considerations is put into context and followed by a practical application based on our ongoing calibration research with a promising online self-report tool called the Youth Activity Profile (YAP). We first describe the overall concept of calibration and how this influences the selection of appropriate self-report tools for this population. We point out the advantages and disadvantages of different monitoring devices since the choice of the criterion measure and the strategies used to minimize error in the measure can dramatically improve the quality of the data. We summarize strategies to ensure quality control in data collection and discuss analytical considerations involved in group- vs individual-level inference. For cross-validation procedures, we describe the advantages of equivalence testing procedures that directly test and quantify agreement. Lastly, we introduce the unique challenges encountered when transitioning from paper to a Web-based tool. The Web offers considerable potential for broad adoption but an iterative calibration approach focused on continued refinement is needed to ensure that estimates are generalizable across individuals, regions, seasons and countries.

  8. The Design of Hydraulic Circuit of Hydraulic Steering Gear for Teaching Test-bed%液压舵机教学实验台液压系统的设计

    Institute of Scientific and Technical Information of China (English)

    卢运娇

    2014-01-01

    为了满足教学和相关科研的需要,笔者所在的教学团队设计了一套液压舵机教学实验台,针对实验台中的液压控制部分进行设计,并介绍其工作原理。该系统具有结构简单,造价成本低,运行安全可靠等优点,无论是在教学上还是科研试验中都将起到积极的作用。%The teaching team designed a set of hydraulic steering gear test-bed for teaching and scientific research.Hydraulic circuit is designed for the test-bed and its working principle is introduced .The hydraulic circuit has the advantages of simple structure, low cost, safe and reliable operation and so on.The design for teaching or for related research will play an active role.

  9. 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...

  10. Hydraulic testing of intravascular axial flow blood pump designs with a protective cage of filaments for mechanical cavopulmonary assist.

    Science.gov (United States)

    Kapadia, Jugal Y; Pierce, Kathryn C; Poupore, Amy K; Throckmorton, Amy L

    2010-01-01

    To provide hemodynamic support to patients with a failing single ventricle, we are developing a percutaneously inserted, magnetically levitated axial flow blood pump designed to augment pressure in the cavopulmonary circulation. The device is designed to serve as a bridge-to-transplant, bridge-to-recovery, bridge-to-hemodynamic stability, or bridge-to-surgical reconstruction. This study evaluated the hydraulic performance of three blood pump prototypes (a four-bladed impeller, a three-bladed impeller, and a three-bladed impeller with a four-bladed diffuser) whose designs evolved from previous design optimization phases. Each prototype included the same geometric protective cage of filaments, which stabilize the rotor within the housing and protect the housing wall from the rotating blades. All prototypes delivered pressure rises over a range of flow rates and rotational speeds that would be sufficient to augment hemodynamic conditions in the cavopulmonary circulation. The four-bladed impeller outperformed the two remaining prototypes by >40%; this design was able to generate a pressure rise of 4-28 mm Hg for flow rates of 0.5-10 L/min at rotational speeds of 4,000-7,000 RPM. Successful development of this blood pump will provide clinicians with a feasible therapeutic option for mechanically supporting the failing Fontan.

  11. Robotic Observatory System Design-Specification Considerations for Achieving Long-Term Sustainable Precision Performance

    Science.gov (United States)

    Wray, J. D.

    2003-05-01

    The robotic observatory telescope must point precisely on the target object, and then track autonomously to a fraction of the FWHM of the system PSF for durations of ten to twenty minutes or more. It must retain this precision while continuing to function at rates approaching thousands of observations per night for all its years of useful life. These stringent requirements raise new challenges unique to robotic telescope systems design. Critical design considerations are driven by the applicability of the above requirements to all systems of the robotic observatory, including telescope and instrument systems, telescope-dome enclosure systems, combined electrical and electronics systems, environmental (e.g. seeing) control systems and integrated computer control software systems. Traditional telescope design considerations include the effects of differential thermal strain, elastic flexure, plastic flexure and slack or backlash with respect to focal stability, optical alignment and angular pointing and tracking precision. Robotic observatory design must holistically encapsulate these traditional considerations within the overall objective of maximized long-term sustainable precision performance. This overall objective is accomplished through combining appropriate mechanical and dynamical system characteristics with a full-time real-time telescope mount model feedback computer control system. Important design considerations include: identifying and reducing quasi-zero-backlash; increasing size to increase precision; directly encoding axis shaft rotation; pointing and tracking operation via real-time feedback between precision mount model and axis mounted encoders; use of monolithic construction whenever appropriate for sustainable mechanical integrity; accelerating dome motion to eliminate repetitive shock; ducting internal telescope air to outside dome; and the principal design criteria: maximizing elastic repeatability while minimizing slack, plastic deformation

  12. Apollo CSM Power Generation System Design Considerations, Failure Modes and Lessons Learned

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    The objectives of this slide presentation are to: review the basic design criteria for fuel cells (FC's), review design considerations during developmental phase that affected Block I and Block II vehicles, summarize the conditions that led to the failure of components in the FC's, and state the solution implemented for each failure. It reviews the location of the fuel cells, the fuel cell theory the design criteria going into development phase and coming from the development phase, failures and solutions of Block I and II, and the lessons learned.

  13. 液压CAT系统模块化设计%The Modular Design of Hydraulic CAT System

    Institute of Scientific and Technical Information of China (English)

    姚凯; 金侠杰; 金健; 白桂豹; 蒋洪雷

    2013-01-01

    Using the A/D module, D/A module and the communication module, this paper realizes the hardware mod-ularization. By developing the functional modules of the program, this paper realizes the software modularization. The modular design of the hydraulic CAT system shortens the development cycle, improves the expansibility and the universality of the CAT system.%  使用PLC的A/D模块、D/A模块和通讯模块实现了液压CAT系统硬件模块化。以LabVIEW为平台开发出各功能模块的程序,并对各模块进行了封装,实现了软件模块化。液压CAT系统的模块化设计,缩短了开发周期,提高了系统设计的扩展性和通用性。

  14. Development of Design Technology on Thermal-Hydraulic Performance in Tight-Lattice Rod Bundles: I-Master Plan and Executive Summary

    Science.gov (United States)

    Ohnuki, Akira; Kureta, Masatoshi; Yoshida, Hiroyuki; Tamai, Hidesada; Liu, Wei; Misawa, Takeharu; Takase, Kazuyuki; Akimoto, Hajime

    R&D project to investigate thermal-hydraulic performance in tight-lattice rod bundles for Innovative Water Reactor for Flexible Fuel Cycle has been progressed at Japan Atomic Energy Agency in collaboration with power utilities, reactor vendors and universities since 2002. In this series-study, we will summarize the R&D achievements using large-scale test facility (37-rod bundle with full-height and full-pressure), model experiments and advanced numerical simulation technology. This first paper described the master plan for the development of design technology and showed an executive summary for this project up to FY2005. The thermal-hydraulic characteristics in the tight-lattice configuration were investigated and the feasibility was confirmed based on the experiments. We have developed the design technology including 3-D numerical simulation one to evaluate the effects of geometry/scale on the thermal-hydraulic behaviors.

  15. Design Considerations of a Transverse Flux Machine for Direct-Drive Wind Turbine Applications

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Tausif; Hasan, Iftekhar; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2017-02-16

    This paper presents the design considerations of a double-sided transverse flux machine (TFM) for direct-drive wind turbine applications. The TFM has a modular structure with quasi-U stator cores and ring windings. The rotor is constructed with ferrite magnets in a flux-concentrating arrangement to achieve high air gap flux density. The design considerations for this TFM with respect to initial sizing, pole number selection, key design ratios, and pole shaping are presented in this paper. Pole number selection is critical in the design process of a TFM because it affects both the torque density and power factor under fixed magnetic and changing electrical loading. Several key design ratios are introduced to facilitate the design procedure. The effect of pole shaping on back-emf and inductance is also analyzed. These investigations provide guidance toward the required design of a TFM for direct-drive applications. The analyses are carried out using analytical and three-dimensional finite element analysis. A prototype is under construction for experimental verification.

  16. Design Considerations of a Transverse Flux Machine for Direct-Drive Wind Turbine Applications: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Tausif; Hasan, Iftekhar; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2017-01-01

    This paper presents the design considerations of a double-sided transverse flux machine (TFM) for direct-drive wind turbine applications. The TFM has a modular structure with quasi-U stator cores and ring windings. The rotor is constructed with ferrite magnets in a flux-concentrating arrangement to achieve high air gap flux density. The design considerations for this TFM with respect to initial sizing, pole number selection, key design ratios, and pole shaping are presented in this paper. Pole number selection is critical in the design process of a TFM because it affects both the torque density and power factor under fixed magnetic and changing electrical loading. Several key design ratios are introduced to facilitate the design procedure. The effect of pole shaping on back-emf and inductance is also analyzed. These investigations provide guidance toward the required design of a TFM for direct-drive applications. The analyses are carried out using analytical and three-dimensional finite element analysis. A prototype is under construction for experimental verification.

  17. Inconsistency in the average hydraulic models used in nuclear reactor design and safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jee Won; Roh, Gyu Hong; Choi, Hang Bok [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    One of important inconsistencies in the six-equation model predictions has been found to be the force experienced by a single bubble placed in a convergent stream of liquid. Various sets of governing equations yield different amount of forces to hold the bubble stationary in a convergent nozzle. By using the first order potential flow theory, it is found that the six-equation model can not be used to estimate the force experienced by a deformed bubble. The theoretical value of the particle stress of a bubble in a convergent nozzle flow has been found to be a function of the Weber number when bubble distortion is allowed. This force has been calculated by using different sets of governing equations and compared with the theoretical value. It is suggested in this study that the bubble size distribution function can be used to remove the presented inconsistency by relating the interfacial variables with different moments of the bubble size distribution function. This study also shows that the inconsistencies in the thermal-hydraulic governing equation can be removed by mechanistic modeling of the phasic interface. 11 refs., 3 figs. (Author)

  18. Design, Modeling, and Analysis of a Novel Hydraulic Energy-Regenerative Shock Absorber for Vehicle Suspension

    Directory of Open Access Journals (Sweden)

    Junyi Zou

    2017-01-01

    Full Text Available To reduce energy consumption or improve energy efficiency, the regenerative devices recently have drawn the public’s eyes. In this paper, a novel hydraulic energy-regenerative shock absorber (HERSA is developed for vehicle suspension to regenerate the vibration energy which is dissipated by conventional viscous dampers into heat waste. At first, the schematic of HERSA is presented and a mathematic model is developed to describe the characteristic of HERSA. Then the parametric sensitivity analysis of the vibration energy is expounded, and the ranking of their influences is k1≫m2>m1>k2≈cs. Besides, a parametric study of HERSA is adopted to research the influences of the key parameters on the characteristic of HERSA. Moreover, an optimization of HERSA is carried out to regenerate more power as far as possible without devitalizing the damping characteristic. To make the optimization results more close to the actual condition, the displacement data of the shock absorber in the road test is selected as the excitation in the optimization. The results show that the RMS of regenerated energy is up to 107.94 W under the actual excitation. Moreover it indicates that the HERSA can improve its performance through the damping control.

  19. Computational fluid dynamics simulation and geometric design of hydraulic turbine draft tube

    Directory of Open Access Journals (Sweden)

    JB Sosa

    2015-10-01

    Full Text Available Any hydraulic reaction turbine is installed with a draft tube that impacts widely the entire turbine performance, on which its functions are as follows: drive the flux in appropriate manner after it releases its energy to the runner; recover the suction head by a suction effect; and improve the dynamic energy in the runner outlet. All these functions are strongly linked to the geometric definition of the draft tube. This article proposes a geometric parametrization and analysis of a Francis turbine draft tube. Based on the parametric definition, geometric changes in the draft tube are proposed and the turbine performance is modeled by computational fluid dynamics; the boundary conditions are set by measurements performed in a hydroelectric power plant. This modeling allows us to see the influence of the draft tube shape on the entire turbine performance. The numerical analysis is based on the steady-state solution of the turbine component flows for different guide vanes opening and multiple modified draft tubes. The computational fluid dynamics predictions are validated using hydroelectric plant measurements. The prediction of the turbine performance is successful and it is linked to the draft tube geometric features; therefore, it is possible to obtain a draft tube parameter value that results in a desired turbine performance.

  20. 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.

  1. Hydraulic elements in reduction of vibrations in mechanical systems

    Science.gov (United States)

    Białas, K.; Buchacz, A.

    2017-08-01

    This work presents non-classical method of design of mechanic systems with subsystem reducing vibrations. The purpose of this paper is also introduces synthesis of mechanic system with reducing vibrations understand as design of this type of systems. The synthesis may be applied to modify the already existing systems in order to achieve a desired result. Elements which reduce vibrations can be constructed with passive, semi-active or active components. These considerations systems have selected active items. A hallmark of active elements it is possible to change the parameters on time of these elements and their power from an external source. The implementation of active elements is very broad. These elements can be implemented through the use of components of electrical, pneumatic, hydraulic, etc. The system was consisted from mechanical and hydraulic elements. Hydraulic elements were used as subsystem reducing unwanted vibration of mechanical system. Hydraulic elements can be realized in the form of hydraulic cylinder. In the case of an active vibration reduction in the form of hydraulic cylinder it is very important to find the corresponding values of hydraulic components. The values of these elements affect the frequency of vibrations of this sub-system which is related to the effective vibration reduction [7,11].

  2. Hydraulic development of high specific-speed pump-turbines by means of an inverse design method, numerical flow-simulation (CFD) and model testing

    Science.gov (United States)

    Kerschberger, P.; Gehrer, A.

    2010-08-01

    In recent years an increased interest in pump-turbines has been recognized in the market. The rapid availability of pumped storage schemes and the benefits to the power system by peak lopping, providing reserve and rapid response for frequency control are becoming of growing advantage. In that context it is requested to develop pump-turbines that reliably stand dynamic operation modes, fast changes of the discharge rate by adjusting the variable diffuser vanes as well as fast changes from pump to turbine operation. Within the present study various flow patterns linked to the operation of a pump-turbine system are discussed. In that context pump and turbine mode are presented separately and different load cases at both operation modes are shown. In order to achieve modern, competitive pump-turbine designs it is further explained which design challenges should be considered during the geometry definition of a pump-turbine impeller. Within the present study a runner-blade profile for a low head pump-turbine has been developed. For the initial hydraulic runner-blade design, an inverse design method has been applied. Within this design procedure, a first blade geometry is generated by imposing the pressure loading-distribution and by means of an inverse 3D potential-flow-solution. The hydraulic behavior of both, pump-mode and turbine-mode is then evaluated by solving the full 3D Navier-Stokes equations in combination with a robust turbulence model. Based on this initial design the blade profile has been further optimized and redesigned considering various hydraulic pump-turbine requirements. Finally, the progress in hydraulic design is demonstrated by model test results which show a significant improvement in hydraulic performance compared to an existing reference design.

  3. Hydraulic development of high specific-speed pump-turbines by means of an inverse design method, numerical flow-simulation (CFD) and model testing

    Energy Technology Data Exchange (ETDEWEB)

    Kerschberger, P; Gehrer, A, E-mail: peter.kerschberger@andritz.co [Andritz Hydro Graz A-8045 Graz, Reichsstrasse 68B (Austria)

    2010-08-15

    In recent years an increased interest in pump-turbines has been recognized in the market. The rapid availability of pumped storage schemes and the benefits to the power system by peak lopping, providing reserve and rapid response for frequency control are becoming of growing advantage. In that context it is requested to develop pump-turbines that reliably stand dynamic operation modes, fast changes of the discharge rate by adjusting the variable diffuser vanes as well as fast changes from pump to turbine operation. Within the present study various flow patterns linked to the operation of a pump-turbine system are discussed. In that context pump and turbine mode are presented separately and different load cases at both operation modes are shown. In order to achieve modern, competitive pump-turbine designs it is further explained which design challenges should be considered during the geometry definition of a pump-turbine impeller. Within the present study a runner-blade profile for a low head pump-turbine has been developed. For the initial hydraulic runner-blade design, an inverse design method has been applied. Within this design procedure, a first blade geometry is generated by imposing the pressure loading-distribution and by means of an inverse 3D potential-flow-solution. The hydraulic behavior of both, pump-mode and turbine-mode is then evaluated by solving the full 3D Navier-Stokes equations in combination with a robust turbulence model. Based on this initial design the blade profile has been further optimized and redesigned considering various hydraulic pump-turbine requirements. Finally, the progress in hydraulic design is demonstrated by model test results which show a significant improvement in hydraulic performance compared to an existing reference design.

  4. Research design considerations for chronic pain prevention clinical trials: IMMPACT recommendations.

    Science.gov (United States)

    Gewandter, Jennifer S; Dworkin, Robert H; Turk, Dennis C; Farrar, John T; Fillingim, Roger B; Gilron, Ian; Markman, John D; Oaklander, Anne Louise; Polydefkis, Michael J; Raja, Srinivasa N; Robinson, James P; Woolf, Clifford J; Ziegler, Dan; Ashburn, Michael A; Burke, Laurie B; Cowan, Penney; George, Steven Z; Goli, Veeraindar; Graff, Ole X; Iyengar, Smriti; Jay, Gary W; Katz, Joel; Kehlet, Henrik; Kitt, Rachel A; Kopecky, Ernest A; Malamut, Richard; McDermott, Michael P; Palmer, Pamela; Rappaport, Bob A; Rauschkolb, Christine; Steigerwald, Ilona; Tobias, Jeffrey; Walco, Gary A

    2015-07-01

    Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment, outcomes, timing of assessment, and adjusting for risk factors in the analyses. We provide a detailed examination of 4 models of chronic pain prevention (ie, chronic postsurgical pain, postherpetic neuralgia, chronic low back pain, and painful chemotherapy-induced peripheral neuropathy). The issues discussed can, in many instances, be extrapolated to other chronic pain conditions. These examples were selected because they are representative models of primary and secondary prevention, reflect persistent pain resulting from multiple insults (ie, surgery, viral infection, injury, and toxic or noxious element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have the potential to reduce the prevalence of chronic pain in the population. Additionally, standardization of outcomes in prevention clinical trials will facilitate meta-analyses and systematic reviews and improve detection of preventive strategies emerging from clinical trials.

  5. 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

  6. 综采工作面液压支架集控系统设计研究%Design of hydraulic support system for hydraulic support in fully mechanized mining face

    Institute of Scientific and Technical Information of China (English)

    唐鹏

    2015-01-01

    In view of the present stage of our country's domestic hydraulic support control system has the problem of poor real-time, low reliability and low degree of automation. This paper designs the hydraulic support system of hydraulic support in the fully mechanized working face, and introduces the hardware and software design of the system. The system has high real-time performance, stable communication, high degree of integration, and can meet the requirements of the establishment of high efifciency fully mechanized coal face.%针对现阶段我国的国产液压支架控制系统有实时性差、可靠性低、自动化程度较低等问题,设计了综采工作面液压支架集控系统,该文介绍了该系统硬件组成与软件设计,分析了液压支架集控的实现过程。该系统实时性高,通信稳定,集控程度高,能满足建立高产高效综采工作面的要求。

  7. Novel dose-finding designs and considerations on practical implementations in oncology clinical trials.

    Science.gov (United States)

    Huang, Bo; Bycott, Paul; Talukder, Enayet

    2017-01-01

    One of the main objectives in phase I oncology trials is to evaluate safety and tolerability of an experimental treatment by estimating the maximum tolerated dose (MTD) based on the rate of dose-limiting toxicities (DLT). To meet emerging challenges in dose-finding studies, over the past two decades, extensive research has been conducted by statistical and medical researchers to create innovative dose finding designs that perform better than the standard 3 + 3 design, which often exhibits undesirable statistical and operational properties. However, clinical implementation and practical usage of these new designs have been limited. This article begins with a review of the most recent literature and then provides some perspectives on implementing novel adaptive dose finding designs in oncology phase I trials from a pharmaceutical industry perspective. Statistical planning and logistical considerations on how to effectively execute such designs in multi-center clinical trials are discussed using two recent case studies.

  8. Effects of Volute Design and Number of Impeller Blades on Lateral Impeller Forces and Hydraulic Performance

    Directory of Open Access Journals (Sweden)

    Daniel O. Baun

    2003-01-01

    Full Text Available A comparison is made between the characteristics of the measured lateral impeller forces and the hydraulic performances of a four- and a five-vane impeller, each operating in a spiral volute, a concentric volute, and a double volute. The pump's rotor was supported in magnetic bearings. In addition to supporting and controlling the rotor motion, the magnetic bearings also served as active load cells and were used to measure the impeller forces acting on the pump's rotor. The lateral impeller force characteristics, as a function of a normalized flow coefficient, were virtually identical in the four- and five-vane impellers in each respective volute type. The measured impeller forces for each volute type were compared with correlations in the literature. The measured forces from the double volute configurations agreed with the forces from a correlation model over the full flow range. Single volute configurations compared well with the predictions of a published correlation at high flow rates, ϕ/ϕn>0.5. Concentric volute configurations compared well with a published correlation at low flow rates, ϕ/ϕn<0.4. The head-versus-flow characteristics of the four-vane impeller in each volute type were stable over a greater flow range than the corresponding characteristics of the five-vane impeller. At higher flow rates in the stable region of the head's characteristic curves near the best efficiency point, the five-vane impeller produced higher head than did the four-vane impeller in each volute type.

  9. Memories and NASA Spacecraft: A Description of Memories, Radiation Failure Modes, and System Design Considerations

    Science.gov (United States)

    LaBel, Kenneth A.; Ladbury, Ray; Oldhamm, Timothy

    2010-01-01

    As NASA has evolved it's usage of spaceflight computing, memory applications have followed as well. In this slide presentation, the history of NASA's memories from magnetic core and tape recorders to current semiconductor approaches is discussed. There is a brief description of current functional memory usage in NASA space systems followed by a description of potential radiation-induced failure modes along with considerations for reliable system design.

  10. Considerations in the design of a communication network for an autonomously managed power system

    Science.gov (United States)

    Mckee, J. W.; Whitehead, Norma; Lollar, Louis

    1989-01-01

    The considerations involved in designing a communication network for an autonomously managed power system intended for use in space vehicles are examined. An overview of the design and implementation of a communication network implemented in a breadboard power system is presented. An assumption that the monitoring and control devices are distributed but physically close leads to the selection of a multidrop cable communication system. The assumption of a high-quality communication cable in which few messages are lost resulted in a simple recovery procedure consisting of a time out and retransmit process.

  11. Residential hospice environments: evidence-based architectural and landscape design considerations.

    Science.gov (United States)

    Verderber, Stephen

    2014-01-01

    The residential hospice care movement is increasingly accepted and supported globally, and yet, unfortunately, the amount of literature on best practices in the planning and design of residential hospice facilities and adjacent outdoor spaces remains relatively small. This paper reports on a compendium of architectural and landscape design considerations that reflect the fundamental dimensions of the residential hospice experience: site and context, arrival spaces, communal and private spaces of the residential milieu, transitional spaces, and nature connectivity. Additionally, key staffing and administrative ramifications of this built-environment compendium are addressed, as are prognostications and challenges for the future.

  12. The preliminary thermal–hydraulic analysis of a water cooled blanket concept design based on RELAP5 code

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guanghuai; Peng, Changhong; Guo, Yun, E-mail: guoyun79@ustc.edu.cn

    2016-11-01

    Highlights: • The superheated steam and PWR schemes are analyzed by RELAP5 code. • The influence of non-uniform heating sources is include. • A supposed slow flow decrease case is discussed and the PWR scheme is better. - Abstract: Water cooled blanket (WCB) is very important in the conceptual design and energy transfer in future fusion power plant. One conceptual design of WCB is under computational testing. RELAP5 code, which is mature and often used in transient analysis in Pressurizer water reactor (PWR), is selected as the simulation tool. The complex inner flow channels and heat sources are simplified according to its thermal–hydraulic characteristics. Then the nodal model for REALP5 is built for approximating the conceptual design. Two typical operating plans, superheated steam scheme and PWR scheme, are analyzed. After some adjustments of the inlet flow resistance coefficients of some flow channels, the reasonable stable conditions of both operation plans can be obtained. The stable fluid and wall temperature distributions and pressure drops are studied. At last, a supposed slow flow decreasing is discussed under two operating conditions separately. According to present results, the superheated steam scheme still needs to be further optimized. The PWR scheme shows a very good safety feature.

  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. Designing for Motivation: Design-Considerations for Spaced-Repetition-Based Learning Games on Mobile Devices

    Science.gov (United States)

    Schimanke, Florian; Mertens, Robert; Vornberger, Oliver

    2017-01-01

    Learning games are an ideal vessel for many kinds of learning content. Playful interaction with the subject matter makes the human mind more receptive and thus learning itself more effective. Well designed games also come with an addictive game-play that makes users want to play the game over and over. This is intended in fun games but it can be…

  15. Single-case research design in pediatric psychology: considerations regarding data analysis.

    Science.gov (United States)

    Cohen, Lindsey L; Feinstein, Amanda; Masuda, Akihiko; Vowles, Kevin E

    2014-03-01

    Single-case research allows for an examination of behavior and can demonstrate the functional relation between intervention and outcome in pediatric psychology. This review highlights key assumptions, methodological and design considerations, and options for data analysis. Single-case methodology and guidelines are reviewed with an in-depth focus on visual and statistical analyses. Guidelines allow for the careful evaluation of design quality and visual analysis. A number of statistical techniques have been introduced to supplement visual analysis, but to date, there is no consensus on their recommended use in single-case research design. Single-case methodology is invaluable for advancing pediatric psychology science and practice, and guidelines have been introduced to enhance the consistency, validity, and reliability of these studies. Experts generally agree that visual inspection is the optimal method of analysis in single-case design; however, statistical approaches are becoming increasingly evaluated and used to augment data interpretation.

  16. PLC程序控制研配液压机的结构设计%Structure Design of Bedding-in Hydraulic Press Controlled by PLC Program

    Institute of Scientific and Technical Information of China (English)

    刘泽民; 付丽; 敖茜; 李慧

    2014-01-01

    The design scheme of bedding-in hydraulic press controlled by PLC was introduced. The bedding-in process,struc-ture,hydraulic system and PLC control process of the bedding-in hydraulic press were analyzed. The program significantly improves the control precision and production efficiency.%介绍了应用PLC技术的研配液压机的设计方案,对该机的研配过程、结构、液压系统和PLC控制过程进行了分析和说明。该方案的提出显著提高了控制精度和生产效率。

  17. 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

  18. Optimum Design of a Moving Coil Actuator for Fast-Switching Valves in Digital Hydraulic Pumps and Motors

    DEFF Research Database (Denmark)

    Roemer, Daniel Beck; Bech, Michael Møller; Johansen, Per

    2015-01-01

    Fast-switching seat valves suitable for digital hydraulic pumps and motors utilize direct electromagnetic actuators, which must exhibit superior transient performance to allow efficient operation of the fluid power pump/motor. A moving coil actuator resulting in a minimum valve switching time.......5 bar at 600 L/min flow rate, enabling efficient operation of digital hydraulic pumps and motors....

  19. Design, Construction, Reliability and Hydraulic Performance of an Innovative Wave Overtopping Device

    DEFF Research Database (Denmark)

    Frigaard, Peter; Andersen, Thomas Lykke; Margheritini, Lucia

    2008-01-01

    concrete structure has been under detailed design in Norway. The construction was planned to be installed during spring and summer 2008 at a small island Kvitsoy situated near Stavanger. Unfortunately environmental issues have demanded a movement of the project to another location. The actual situation......The SSG (Sea Slot-cone Generator) is a wave energy converter of the overtopping type. The structure consists of a number of reservoirs one on the top of each others above the mean water level, in which the water of incoming waves is stored temporary. In each reservoir, expressively designed low...... is that some breakwaters under design are being investigated as a possible places for integrating the SSG structure. The paper describes the concept of the SSG wave energy converter, the structure and the studies that led to its design....

  20. Mechatronic System Design and Intelligent Motion Control of Hydraulic Robots and Machines

    DEFF Research Database (Denmark)

    Conrad, Finn; Sørensen, Torben

    2003-01-01

    integration of an overall design and manufacturing IT- concept feasible and commercially attractive. An IT-tool concept for modelling, simulation and design of mechatronic products and systems is proposed in this paper. It built on results from a Danish mechatronic research program on intelligent motion...... controller utilizes the dSPACE System suitable for real-time experimentation, evaluation and validation of control laws and algorithms....

  1. 液压支架电液控制系统急停控制功能的设计与实现%Design and realization on emergency stop control function of electro-hydraulic control system of hydraulic support

    Institute of Scientific and Technical Information of China (English)

    牛一村

    2016-01-01

    针对液压支架电液控制系统运行特点,提出了液压支架电液控制系统急停控制功能整体设计方案,通过基于单线 CAN 总线的急停通信电路实现了全系统的急停功能,并具有急停触发和解除时的高亮高分贝报警功能,能够在所有支架控制器上显示急停触发位置,对于系统通信故障、支架控制器复位及急停按钮损坏等故障有较好的适应能力,经过功能和性能测试,验证了该方案的可行性。%According to the operation characteristics of the electro-hydraulic control system of the hydraulic support, the paper proposed the whole design scheme to realize emergency stop control function of the electro-hydraulic control system of the hydraulic support, and the emergency stop of the whole system realized via the emergency stop circuit based on single-line CAN bus. In addition, highlighted and high decibel alarm took effect on emergency stop and release, and emergency stop triggering position displayed on all the support controllers. It possessed excellent adaptability for the faults about system communication, reset of support controller and damage of emergency button, and proved feasible after function and performance test.

  2. Experimental and Parametric Design of Petroleum Back-pressured Hydraulic Impactor

    Institute of Scientific and Technical Information of China (English)

    YUAN Guang-jie; YAO Zhen-qiang; CHEN Ping; HUANG Wan-zhi

    2005-01-01

    Percussive-rotary drilling technology was considered many years ago as one of the best approaches for hard rock drilling. It is a key for popularizing this technology on a large scale to design and make an impactor with excellent performance. This paper presents a suit of method to design the percussive parameters for the oil or gas field by introducing the working principle of back-pressured impactor, dividing the working periods of impactor into three phases and establishing the computer emulational model of percussive parameters. It draws a comparison between the results of model calculation and experiment on the basis of analyzing the experiment results of impactor.The conclude provides credible foundation for designing and further ameliorating the impactor.

  3. Optimization of hydraulic dampers with the use of Design For Six Sigma methodology

    Directory of Open Access Journals (Sweden)

    D. Sławik

    2010-12-01

    Full Text Available Purpose: The aims of this paper are to identify the root cause of the temporary decrease in the damping force which occurs during the early stage of the stroking cycle’s compression phase, the so-called damping lag, to describe measures of the phenomenon and to present methods for optimizing the design towards minimizing this (negative effect.Design/methodology/approach: A theoretical background is presented in a constructive and computable manner with emphasis on data-driven modeling. The Design For Six Sigma (DFFS approach and tools were used to validate the model statistically and, more importantly, to propose a method for data-driven optimization of the design.Findings: The root cause of the damping lag was confirmed during model validation as being a result of oil aeration. DFFS methodology proved to be useful in achieving design optimality.Research limitations/implications: The statistical model and conclusions drawn from it are only valid in the interior of the investigated region of the parameter space. Additionally, it might not be possible to find a local minimum of the aeration measure (damping lag inside the selected region of the parameter space; a/the (depending on the context global minimum located at the boundary might be the only possible solution.Practical implications: The optimal value of parameters is not unique and thus additional sub-criteria (cost/durability can be imposed. Conducting tests in an organized manner and according to the Six Sigma methodology allows the design optimization process to be expedited and unnecessary costs to be eliminated.Originality/value: Improvements in understanding and measuring aeration effects constitute a clear foundation for further product optimization. Signal post-processing algorithms are essential for the statistical analysis and are the original contribution of this work.

  4. Analysis and design consideration of mean temperature differential Stirling engine for solar application

    Energy Technology Data Exchange (ETDEWEB)

    Tlili, Iskander; Timoumi, Youssef; Nasrallah, Sassi Ben [Laboratoire d' Etude des Systemes Thermiques et Energetiques Ecole Nationale d' Ingenieurs de Monastir, Rue Ibn El Jazzar, 5019 Monastir (Tunisia)

    2008-08-15

    This article presents a technical innovation, study of solar power system based on the Stirling dish (SD) technology and design considerations to be taken in designing of a mean temperature differential Stirling engine for solar application. The target power source will be solar dish/Stirling with average concentration ratio, which will supply a constant source temperature of 320{sup o}C. Hence, the system design is based on a temperature difference of 300{sup o}C, assuming that the sink is kept at 20{sup o}C. During the preliminary design stage, the critical parameters of the engine design are determined according to the dynamic model with losses energy and pressure drop in heat exchangers was used during the design optimisation stage in order to establish a complete analytical model for the engine. The heat exchangers are designed to be of high effectiveness and low pressure-drop. Upon optimisation, for given value of difference temperature, operating frequency and dead volume there is a definite optimal value of swept volume at which the power is a maximum. The optimal swept volume of 75 cm{sup 3} for operating frequency 75 Hz with the power is 250 W and the dead volume is of 370 cm{sup 3}. (author)

  5. System and antenna design considerations for highly elliptical orbits as applied to the proposed Archimedes Constellation

    Science.gov (United States)

    Paynter, C.; Cuchanski, M.

    1995-01-01

    The paper discusses various aspects of the system design for a satellite in a highly elliptical inclined orbit, and presents a number of antenna design options for the proposed Archimedes mission. A satellite constellation was studied for the provision of multi media communication services in the L and S Band for northern latitudes. The inclined elliptical orbit would allow coverage of Europe, America, and East Asia. Using Canada and North America as the baseline coverage area, this paper addresses system considerations such as the satellite configuration and pointing, beam configuration, and requirements for antennas. A trade-off is performed among several antenna candidates including a direct radiating array, a focal-fed reflector, and a single reflector imaging system. Antenna geometry, performance, and beam forming methods are described. The impact of the designs on the antenna deployment is discussed.

  6. Some important considerations in the design of a quiet compressor station

    Energy Technology Data Exchange (ETDEWEB)

    Binek, J.

    1996-08-01

    Some considerations in the design of power generating plants using natural gas compressors were discussed from the point of view of noise control, affecting not only operating personnel but also residents in the surrounding community. Among these were: (1) determination of noise sources (engine inlet, engine casing, engine exhaust, booster compressor, yard piping and valves, gas aftercoolers, blow-off valves), (2) understanding sound attenuation phenomena (hemispheric divergence, wind, temperature, molecular absorption and ground cover), (3) the importance of low frequency noise, and (4) the shortcomings of dBA as a noise descriptor. Noise control systems should be designed concurrently with the design of the new facility, or the expansion of an old one, recognizing that peaceful coexistence with the surrounding community is an essential ingredient of success. 7 refs., 12 figs.

  7. Zebrafish housing systems: a review of basic operating principles and considerations for design and functionality.

    Science.gov (United States)

    Lawrence, Christian; Mason, Timothy

    2012-01-01

    The strategies for housing zebrafish used in biomedical research have evolved considerably over the past three decades. To keep pace with the rapid expansion and development of the zebrafish model system, the field has generally moved from keeping fish at the level of aquarium hobbyist to that of industrialized, recirculating aquaculture. Numerous commercial system vendors now offer increasingly sophisticated housing systems based on design principles that maximize the number of animals that can be housed in a given space footprint, and they are thus able to support large and diverse research programs. This review is designed to provide managers, lab animal veterinarians, investigators, and other parties responsible for care and use of these animals with a comprehensive overview of the basic operating and design principles of zebrafish housing systems. This information can be used to help plan the construction of new facilities and/or the upgrade and maintenance of existing operations.

  8. 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;

  9. Material Control and Accounting Design Considerations for High-Temperature Gas Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Trond Bjornard; John Hockert

    2011-08-01

    The subject of this report is domestic safeguards and security by design (2SBD) for high-temperature gas reactors, focusing on material control and accountability (MC&A). The motivation for the report is to provide 2SBD support to the Next Generation Nuclear Plant (NGNP) project, which was launched by Congress in 2005. This introductory section will provide some background on the NGNP project and an overview of the 2SBD concept. The remaining chapters focus specifically on design aspects of the candidate high-temperature gas reactors (HTGRs) relevant to MC&A, Nuclear Regulatory Commission (NRC) requirements, and proposed MC&A approaches for the two major HTGR reactor types: pebble bed and prismatic. Of the prismatic type, two candidates are under consideration: (1) GA's GT-MHR (Gas Turbine-Modular Helium Reactor), and (2) the Modular High-Temperature Reactor (M-HTR), a derivative of Areva's Antares reactor. The future of the pebble-bed modular reactor (PBMR) for NGNP is uncertain, as the PBMR consortium partners (Westinghouse, PBMR [Pty] and The Shaw Group) were unable to agree on the path forward for NGNP during 2010. However, during the technology assessment of the conceptual design phase (Phase 1) of the NGNP project, AREVA provided design information and technology assessment of their pebble bed fueled plant design called the HTR-Module concept. AREVA does not intend to pursue this design for NGNP, preferring instead a modular reactor based on the prismatic Antares concept. Since MC&A relevant design information is available for both pebble concepts, the pebble-bed HTGRs considered in this report are: (1) Westinghouse PBMR; and (2) AREVA HTR-Module. The DOE Office of Nuclear Energy (DOE-NE) sponsors the Fuel Cycle Research and Development program (FCR&D), which contains an element specifically focused on the domestic (or state) aspects of SBD. This Material Protection, Control and Accountancy Technology (MPACT) program supports the present work

  10. 掩护式液压支架的优化设计%Optimization Design for Hydraulic-support of Shield

    Institute of Scientific and Technical Information of China (English)

    张闯; 杨琳琳

    2014-01-01

    液压支架对支护顶板的管理能力由四连杆结构参数决定。本文以顶梁前端运动轨迹为目标函数,建立了支架几何运动模型,应用混沌粒子群算法对 ZY6000进行了优化设计。通过对比分析,优化的参数合理可靠,提高了支架的运动特性,为液压支架的设计方法提供了一个新的参考。%The capability of managing roof of the hydraulic support is determined by four-linkage structure parameters . In this paper , taken the front of the top beam motion curve as the objective function , the motion model of hydraulic support is established , and the design of ZY6000 is optimized by chaotic particle swarm algorithm . Through the comparative analysis , the optimization of the parameters is reasonable and reliable, and improves the motion performance of the hydraulic support . The result provides a new reference for the design of hydraulic support .

  11. Conceptual Thermal Hydraulic Design of a 20MW Multipurpose Research Reactor (KAERI/VAEC joint study on a new research reactor for Vietnam)

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Hee Taek; Seo, Chul Gyo; Park, Jong Hark; Park, Cheol [Kaeri, Daejeon (Korea, Republic of); Vinh, Le Vinh; Nghiem, Huynh Ton; Dang, Vo Doan Hai [Dalat Nuclear Research Reactor, Hanoi (Viet Nam)

    2007-08-15

    The conceptual thermal hydraulics design analyses for the 20 MW reference AHR core have been jointly performed by the KAERI and DNRI(VAEC). The preliminary core thermal hydraulic characteristics and safety margins for the AHR core were studied for various core flow rates, fuel assembly powers and core inlet temperatures. Statistical method was applied to the thermal hydraulic design of the reactor core. The MATRA{sub h} subchannel code has been applied to evaluate the thermal hydraulic performances of the AHR and the resulting thermal margins of the core under the forced convection cooling mode during a nominal power operation and the natural circulation mode during a reactor shutdown condition. In addition, typical accident analyses were carried out for a loss of flow accident by a primary pump seizure and a reactivity induced accident by a CAR rod withdrawal during a normal full power operation. The normal full power operation of the AHR was ensured with a sufficient safety margin for the onset of nucleate boiling phenomena. The AHR also had a sufficient natural circulation cooling capability to cool the core without the onset of nucleate boiling in the channel after a normal reactor shutdown and the anticipated transients. It was confirmed by the typical accident analyses that the AHR core was sufficiently protected from the loss of flow by the primary cooling pump seizure and the overpower transients by the CAR withdrawal from the MCHFR and fuel temperature points of view.

  12. 基于PLC的多层液压电梯控制系统设计%Design of Multi-layer Hydraulic Elevator Control System Based on PLC

    Institute of Scientific and Technical Information of China (English)

    刘忠; 陈佳; 邹宇

    2014-01-01

    According to the hydraulic elevator speed control system, this paper puts forward the principle of hy-draulic elevator speed control system based on Siemens S7-200PLC controller, hardware configuration and con-trol method. Based on the special requirement of hydraulic elevator, the paper designs a complete electrical prin-ciple and wiring diagram, and provides a new design idea for the hydraulic elevator control system.%针对液压电梯调速系统的要求,基于西门子S7-200PLC控制器,提出了液压电梯速度控制系统的原理、硬件配置及控制方法。结合液压电梯的特殊要求,设计了完整的电气原理以及接线方式图,为液压电梯控制系统提供了一种新的设计思路。

  13. Design of active disturbance rejection controller for the hydraulic APC system of the rolling mill

    Science.gov (United States)

    Zhang, Ruicheng; Chen, Zhikun

    2011-10-01

    Considering uncertain external disturbance, the model of automatic position control system is established. Then, according to the information of input and output, using extended states observer (ESO), a newer observer is proposed to observe and compensate this integrated disturbance, and a controller is designed based on active disturbance rejection control (ADRC). This controller has very strong robustness not only to external disturbance, but also to unpredictable plant parameter variations.

  14. Proof test on thermal and hydraulic design reliability of Japanese PWR fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Mamoru (Univ. of Tokyo (Japan)); Inoue, Akira (Tokyo Institute of Technology (Japan)); Miyazaki, Keiji (Osaka Univ. (Japan)); Abeta, Sadaaki (Mitsubishi, Tokyo (Japan)); Hori, Keiichi (Mitsubishi, Hyogo (Japan)); Mukasa, Tomio; Oishi, Masao; Aoki, Toshimasa; Makihara, Yoshiaki

    1990-01-01

    A series of departure from nucleate boiling (DNB) tests for pressurized water reactors (PWRs) was performed at the Nuclear Power Engineering Test Center. The objective was to prove the reliability of fuel assembly design by confirming the thermal margin of heat transfer. The present method for evaluating the DNB ratio in a Japanese 17 x 17 PWR core is adequate according to the newly obtained DNB test data.

  15. Design Considerations and Experimental Verification of a Rail Brake Armature Based on Linear Induction Motor Technology

    Science.gov (United States)

    Sakamoto, Yasuaki; Kashiwagi, Takayuki; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

    This paper describes the design considerations and experimental verification of an LIM rail brake armature. In order to generate power and maximize the braking force density despite the limited area between the armature and the rail and the limited space available for installation, we studied a design method that is suitable for designing an LIM rail brake armature; we considered adoption of a ring winding structure. To examine the validity of the proposed design method, we developed a prototype ring winding armature for the rail brakes and examined its electromagnetic characteristics in a dynamic test system with roller rigs. By repeating various tests, we confirmed that unnecessary magnetic field components, which were expected to be present under high speed running condition or when a ring winding armature was used, were not present. Further, the necessary magnetic field component and braking force attained the desired values. These studies have helped us to develop a basic design method that is suitable for designing the LIM rail brake armatures.

  16. Design considerations for a LORAN-C timing receiver in a hostile signal to noise environment

    Science.gov (United States)

    Porter, J. W.; Bowell, J. R.; Price, G. E.

    1981-01-01

    The environment in which a LORAN-C Timing Receiver may function effectively depends to a large extent on the techniques utilized to insure that interfering signals within the pass band of the unit are neutralized. The baseline performance manually operated timing receivers is discussed and the basic design considerations and necessary parameters for an automatic unit utilizing today's technology are established. Actual performance data is presented comparing the results obtained from a present generation timing receiver against a new generation microprocessor controlled automatic acquisition receiver. The achievements possible in a wide range of signal to noise situations are demonstrated.

  17. Note: Design considerations and characterization of a flexible snapshot hyperspectral probe

    Science.gov (United States)

    Lim, Hoong-Ta; Murukeshan, Vadakke Matham

    2017-03-01

    Hyperspectral imaging is a combination of imaging and spectroscopy to give detailed spectral information for each spatial point in the imaged scene. Using the concept of integral field spectroscopy, a custom fabricated two-dimensional to one-dimensional fiber bundle has recently been reported. It is used as a flexible snapshot hyperspectral probe, which can be used as an endoscope for biomedical applications. This paper reports on the design considerations of the fiber bundle as the flexible probe in the snapshot hyperspectral imaging system. The physical characterization of the custom fabricated fiber bundle and lateral resolution of the developed hyperspectral imaging system are also analyzed and described.

  18. Design and optimization of the WEST ICRH antenna front face components based on thermal and hydraulic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhaoxi, E-mail: chenzx@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); University of Science and Technology of China, Hefei 230026 (China); Vulliez, Karl [Laboratoire d’étanchéité, DEN/DTEC/SDTC, Commissariat à l’énergie atomique et aux énergies alternatives, 2 rue James Watt, 26700 Pierrelatte (France); Ferlay, Fabien; Martinez, André; Mollard, Patrick; Hillairet, Julien; Doceul, Louis; Bernard, Jean-Michel; Larroque, Sébastien; Helou, Walid [CEA, IRFM, F-13108, Saint-Paul-Lez-Durance (France); Song, Yuntao; Yang, Qingxi; Wang, Yongsheng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-05-15

    Highlights: • Three ICRH antennas are designed to realize continuous-wave operation. • Fully active cooling structure is designed which takes the balance of structure safety and cooling performance. • High cooling efficiency is achieved for the current cooling circuit design based on the thermal-hydraulic simulation. - Abstract: The WEST (Tungsten (W) Environment in Steady-state Tokamak) is an upgrade of Tore-Supra (TS) which aims it into an X-point magnetic configuration tokamak equipped with an actively cooled tungsten divertor. To be a platform of ITER technologies of high heat flux components testing, three sets of Ion Cyclotron Resonant Heating (ICRH) antennas have been designed to inject 9 MW during 30 s or 3 MW during 1000 s. The antenna design is based on a load resilient prototype successfully tested in Tore Supra in 2007. In order to allow continuous-wave (CW) operations, the mechanical design of the WEST ICRH antenna is emphasized on its cooling performances by designing fully active cooling structure. Two kinds of cooling water loops are used, with temperature and pressure of 70 °C/30 bar and 25 °C/5.2 bar, respectively. The hot water loop is used for the Faraday screen (FS) and the housing box (HB), while the cold water loop is used for the straps, the matching capacitors and the impedance transformer. To enhance the heat removal ability and control the pressure drop, the cooling channels in the FS and HB are drilled directly and parallel connected as much as possible. By performing the hydraulic–thermal analysis, the lack of cooling efficiency was found in the front face of lateral collector where 1 MW/m{sup 2} is imposed and fluid dead zones were found in some of the bars. After optimization, the cooling performance of the cooling circuit increased significantly. With a mass flow rate of 2.5 kg/s, the total pressure drop is 3.1 bar, and the peak temperatures on the FS and HB are 500 °C and 261 °C, respectively. Besides, no cavitation is

  19. Research on design and manufacturing methods of hydraulic valve blocks%液压集成阀块设计及制造方法研究

    Institute of Scientific and Technical Information of China (English)

    禹阳华; 程度旺; 黄长发

    2012-01-01

    阐述了液压集成阀块的设计要点、油道通径及材料的选择,指出了阀块机加工需注意的问题,举例说明了阀块设计的具体过程,对液压集成阀块的设计与制造具有指导意义.%The paper presents key points of design, and selection of orifice diameter and material of hydraulic valve blocks, as well as specific problems requiring high attention for machining valve blocks. In addition, the paper shows detailed process for design of valve blocks, which gives guidance to design and manufacturing of the hydraulic valve blocks.

  20. 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...

  1. Improving the Hydraulic Efficiency of Centrifugal Pumps through Computational Fluid Dynamics Based Design optimization

    Directory of Open Access Journals (Sweden)

    Abdellah Ait moussa

    2014-08-01

    Full Text Available The design and optimization of turbo machine impellers such as those in pumps and turbines is a highly complicated task due to the complex three-dimensional shape of the impeller blades and surrounding devices. Small differences in geometry can lead to significant changes in the performance of these machines. We report here an efficient numerical technique that automatically optimizes the geometry of these blades for maximum performance. The technique combines, mathematical modeling of the impeller blades using non-uniform rational B-spline (NURBS, Computational fluid dynamics (CFD with Geometry Parameterizations in turbulent flow simulation and the Globalized and bounded Nelder-Mead (GBNM algorithm in geometry optimization.

  2. 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.

  3. Design considerations for a time-resolved tomographic diagnostic at DARHT

    Energy Technology Data Exchange (ETDEWEB)

    Morris I. Kaufman, Daniel Frayer, Wendi Dreesen, Douglas Johnson, Alfred Meidinger

    2006-08-01

    An instrument has been developed to acquire time-resolved tomographic data from the electron beam at the DARHT [Dual-Axis Radiographic Hydrodynamic Test] facility at Los Alamos National Laboratory. The instrument contains four optical lines of sight that view a single tilted object. The lens design optically integrates along one optical axis for each line of sight. These images are relayed via fiber optic arrays to streak cameras, and the recorded streaks are used to reconstruct the original two-dimensional data. Installation of this instrument into the facility requires automation of both the optomechanical adjustments and calibration of the instrument in a constrained space. Additional design considerations include compound tilts on the object and image planes.

  4. Design Considerations for Scalable High-Performance Vision Systems Embedded in Industrial Print Inspection Machines

    Directory of Open Access Journals (Sweden)

    Rössler Peter

    2007-01-01

    Full Text Available This paper describes the design of a scalable high-performance vision system which is used in the application area of optical print inspection. The system is able to process hundreds of megabytes of image data per second coming from several high-speed/high-resolution cameras. Due to performance requirements, some functionality has been implemented on dedicated hardware based on a field programmable gate array (FPGA, which is coupled to a high-end digital signal processor (DSP. The paper discusses design considerations like partitioning of image processing algorithms between hardware and software. The main chapters focus on functionality implemented on the FPGA, including low-level image processing algorithms (flat-field correction, image pyramid generation, neighborhood operations and advanced processing units (programmable arithmetic unit, geometry unit. Verification issues for the complex system are also addressed. The paper concludes with a summary of the FPGA resource usage and some performance results.

  5. 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...

  6. A Frequency Response Approach to Sliding Control Design for Hydraulic Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Johansen, Per; Andersen, Torben Ole

    2014-01-01

    Sliding modes applied in control structures may generally provide for perfect control performance and robustness toward uncertain bounded parameters and disturbances, in the ideal case with infinite actuator bandwidth and switching frequency. However, in the context of physical systems......, such performance cannot be realized due to finite actuator bandwidths and switching frequencies, which, in the case of direct application of sliding control terms, may lead to control chattering and high frequency oscillations in the system states. In order to compensate for this undesirable effect......, the application of so-called boundary layers are commonly applied, guaranteeing sliding precision in some well-defined vicinity of the control target. Commonly the control target, or sliding manifold, is designed as some desired closed loop dynamics of the controlled plant, utilizing multiple states as feedback...

  7. 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.

  8. Development and design of a dynamic armrest for hydraulic-actuation joystick controlled mobile machines.

    Science.gov (United States)

    Murphy, T; Oliver, M L

    2008-05-01

    Standard armrests used in conjunction with joysticks of heavy mobile machinery have been proven to inadequately meet operator needs, resulting in excessive static loading of shoulder musculature. During joystick operation, the trajectory of the user's forearm is governed by the motion of the controller, which creates horizontal and vertical movement of the forearm. The vertical motion of the forearm in the forward and backward motion create postures that stationary armrests cannot support thereby generating increased muscle activation and risk of repetitive strain injuries. The current paper describes the design process used in creating a dynamic armrest that replicates the operator's natural motion trajectories. By incorporating the natural motion paths into a dynamic armrest, the postural requirements and muscular activation of the operator's shoulder may be reduced.

  9. Research design considerations for confirmatory chronic pain clinical trials: IMMPACT recommendations.

    Science.gov (United States)

    Dworkin, Robert H; Turk, Dennis C; Peirce-Sandner, Sarah; Baron, Ralf; Bellamy, Nicholas; Burke, Laurie B; Chappell, Amy; Chartier, Kevin; Cleeland, Charles S; Costello, Ann; Cowan, Penney; Dimitrova, Rozalina; Ellenberg, Susan; Farrar, John T; French, Jacqueline A; Gilron, Ian; Hertz, Sharon; Jadad, Alejandro R; Jay, Gary W; Kalliomäki, Jarkko; Katz, Nathaniel P; Kerns, Robert D; Manning, Donald C; McDermott, Michael P; McGrath, Patrick J; Narayana, Arvind; Porter, Linda; Quessy, Steve; Rappaport, Bob A; Rauschkolb, Christine; Reeve, Bryce B; Rhodes, Thomas; Sampaio, Cristina; Simpson, David M; Stauffer, Joseph W; Stucki, Gerold; Tobias, Jeffrey; White, Richard E; Witter, James

    2010-05-01

    There has been an increase in the number of chronic pain clinical trials in which the treatments being evaluated did not differ significantly from placebo in the primary efficacy analyses despite previous research suggesting that efficacy could be expected. These findings could reflect a true lack of efficacy or methodological and other aspects of these trials that compromise the demonstration of efficacy. There is substantial variability among chronic pain clinical trials with respect to important research design considerations, and identifying and addressing any methodological weaknesses would enhance the likelihood of demonstrating the analgesic effects of new interventions. An IMMPACT consensus meeting was therefore convened to identify the critical research design considerations for confirmatory chronic pain trials and to make recommendations for their conduct. We present recommendations for the major components of confirmatory chronic pain clinical trials, including participant selection, trial phases and duration, treatment groups and dosing regimens, and types of trials. Increased attention to and research on the methodological aspects of confirmatory chronic pain clinical trials has the potential to enhance their assay sensitivity and ultimately provide more meaningful evaluations of treatments for chronic pain.

  10. Hydraulic System Design of Electric Log Splitter%电动液压劈木机液压系统设计

    Institute of Scientific and Technical Information of China (English)

    孙增忠

    2014-01-01

    采用液压原理,设计了一款外形美观、移动方便、符合德国“GS”标准的电动卧式液压劈木机。针对设计开发过程中出现的保压和德国“GS”标准中要求双手操作的安全要求等问题,一是设计了三位三通液压控制阀,有效解决了双手操作问题;二是提高齿轮泵、液压控制阀等关键件的制造精度,加强关键件组装工序检验和控制手段,使劈木机压力得到了保证。结果表明:液压技术在电动工具中应用,具有一定的发展前景,电动卧式液压劈木机可以系列化,以满足不同客户要求。%Based on the hydraulic principle , it designs a good appearance , which is mobile convenience and up to the standard of Germany "GS"electric horizontal hydraulic log splitter .In view of this machine characteristic such as keeping the pressure and Germany "GS"hands operation safety in the standard requirement , it designs a hydraulic control valve with three tee to solve the problem of the hands operation , improves the manufacturing precision of the gear pump , hydraulic control valves , strengthens the key -module assembly process inspection and control means .These make the splitting machine obtain satisfactory pressure .The results show that the hy-draulic technology can be used in electric tools and have a certain development prospects .

  11. Hydraulic design to optimize the treatment capacity of Multi-Stage Filtration units

    Science.gov (United States)

    Mushila, C. N.; Ochieng, G. M.; Otieno, F. A. O.; Shitote, S. M.; Sitters, C. W.

    2016-04-01

    Multi-Stage Filtration (MSF) can provide a robust treatment alternative for surface water sources of variable water quality in rural communities at low operation and maintenance costs. MSF is a combination of Slow Sand Filters (SSFs) and Pre-treatment systems. The general objective of this research was to optimize the treatment capacity of MSF. A pilot plant study was undertaken to meet this objective. The pilot plant was monitored for a continuous 98 days from commissioning till the end of the project. Three main stages of MSF namely: The Dynamic Gravel Filter (DGF), Horizontal-flow Roughing Filter (HRF) and SSF were identified, designed and built. The response of the respective MSF units in removal of selected parameters guiding drinking water quality such as microbiological (Faecal and Total coliform), Suspended Solids, Turbidity, PH, Temperature, Iron and Manganese was investigated. The benchmark was the Kenya Bureau (KEBS) and World Health Organization (WHO) Standards for drinking water quality. With respect to microbiological raw water quality improvement, MSF units achieved on average 98% Faecal and 96% Total coliform removal. Results obtained indicate that implementation of MSF in rural communities has the potential to increase access to portable water to the rural populace with a probable consequent decrease in waterborne diseases. With a reduced down time due to illness, more time would be spent in undertaking other economic activities.

  12. Development of Design Technology on Thermal-Hydraulic Performance in Tight-Lattice Rod Bundles: III - Numerical Evaluation of Fluid Mixing Phenomena using Advanced Interface-Tracking Method -

    Science.gov (United States)

    Yoshida, Hiroyuki; Nagayoshi, Takuji; Takase, Kazuyuki; Akimoto, Hajime

    Thermal-hydraulic design of the current boiling water reactor (BWR) is performed by correlations with empirical results of actual-size tests. However, for the Innovative Water Reactor for Flexible Fuel Cycle (FLWR) core, an actual size test of an embodiment of its design is required to confirm or modify such correlations. Development of a method that enables the thermal-hydraulic design of nuclear reactors without these actual size tests is desired, because these tests take a long time and entail great cost. For this reason we developed an advanced thermal-hydraulic design method for FLWRs using innovative two-phase flow simulation technology. In this study, detailed Two-Phase Flow simulation code using advanced Interface Tracking method: TPFIT is developed to calculate the detailed information of the two-phase flow. We tried to verify the TPFIT code by comparing it with the 2-channel air-water and steam-water mixing experimental results. The predicted result agrees well the observed results and bubble dynamics through the gap and cross flow behavior could be effectively predicted by the TPFIT code, and pressure difference between fluid channels is responsible for the fluid mixing.

  13. The Design Method of Axial Flow Runners Focusing on Axial Flow Velocity Uniformization and Its Application to an Ultra-Small Axial Flow Hydraulic Turbine

    Directory of Open Access Journals (Sweden)

    Yasuyuki Nishi

    2016-01-01

    Full Text Available We proposed a portable and ultra-small axial flow hydraulic turbine that can generate electric power comparatively easily using the low head of open channels such as existing pipe conduits or small rivers. In addition, we proposed a simple design method for axial flow runners in combination with the conventional one-dimensional design method and the design method of axial flow velocity uniformization, with the support of three-dimensional flow analysis. Applying our design method to the runner of an ultra-small axial flow hydraulic turbine, the performance and internal flow of the designed runner were investigated using CFD analysis and experiment (performance test and PIV measurement. As a result, the runners designed with our design method were significantly improved in turbine efficiency compared to the original runner. Specifically, in the experiment, a new design of the runner achieved a turbine efficiency of 0.768. This reason was that the axial component of absolute velocity of the new design of the runner was relatively uniform at the runner outlet in comparison with that of the original runner, and as a result, the negative rotational flow was improved. Thus, the validity of our design method has been verified.

  14. Planning Considerations for a Mars Sample Receiving Facility: Summary and Interpretation of Three Design Studies

    Science.gov (United States)

    Beaty, David W.; Allen, Carlton C.; Bass, Deborah S.; Buxbaum, Karen L.; Campbell, James K.; Lindstrom, David J.; Miller, Sylvia L.; Papanastassiou, Dimitri A.

    2009-10-01

    It has been widely understood for many years that an essential component of a Mars Sample Return mission is a Sample Receiving Facility (SRF). The purpose of such a facility would be to take delivery of the flight hardware that lands on Earth, open the spacecraft and extract the sample container and samples, and conduct an agreed-upon test protocol, while ensuring strict containment and contamination control of the samples while in the SRF. Any samples that are found to be non-hazardous (or are rendered non-hazardous by sterilization) would then be transferred to long-term curation. Although the general concept of an SRF is relatively straightforward, there has been considerable discussion about implementation planning. The Mars Exploration Program carried out an analysis of the attributes of an SRF to establish its scope, including minimum size and functionality, budgetary requirements (capital cost, operating costs, cost profile), and development schedule. The approach was to arrange for three independent design studies, each led by an architectural design firm, and compare the results. While there were many design elements in common identified by each study team, there were significant differences in the way human operators were to interact with the systems. In aggregate, the design studies provided insight into the attributes of a future SRF and the complex factors to consider for future programmatic planning.

  15. Planning considerations for a Mars Sample Receiving Facility: summary and interpretation of three design studies.

    Science.gov (United States)

    Beaty, David W; Allen, Carlton C; Bass, Deborah S; Buxbaum, Karen L; Campbell, James K; Lindstrom, David J; Miller, Sylvia L; Papanastassiou, Dimitri A

    2009-10-01

    It has been widely understood for many years that an essential component of a Mars Sample Return mission is a Sample Receiving Facility (SRF). The purpose of such a facility would be to take delivery of the flight hardware that lands on Earth, open the spacecraft and extract the sample container and samples, and conduct an agreed-upon test protocol, while ensuring strict containment and contamination control of the samples while in the SRF. Any samples that are found to be non-hazardous (or are rendered non-hazardous by sterilization) would then be transferred to long-term curation. Although the general concept of an SRF is relatively straightforward, there has been considerable discussion about implementation planning. The Mars Exploration Program carried out an analysis of the attributes of an SRF to establish its scope, including minimum size and functionality, budgetary requirements (capital cost, operating costs, cost profile), and development schedule. The approach was to arrange for three independent design studies, each led by an architectural design firm, and compare the results. While there were many design elements in common identified by each study team, there were significant differences in the way human operators were to interact with the systems. In aggregate, the design studies provided insight into the attributes of a future SRF and the complex factors to consider for future programmatic planning.

  16. Advanced tokamak reactors based on the spherical torus (ATR/ST). Preliminary design considerations

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.L.; Krakowski, R.A.; Bathke, C.G.; Copenhaver, C.; Schnurr, N.M.; Engelhardt, A.G.; Seed, T.J.; Zubrin, R.M.

    1986-06-01

    Preliminary design results relating to an advanced magnetic fusion reactor concept based on the high-beta, low-aspect-ratio, spherical-torus tokamak are summarized. The concept includes resistive (demountable) toroidal-field coils, magnetic-divertor impurity control, oscillating-field current drive, and a flowing liquid-metal breeding blanket. Results of parametric tradeoff studies, plasma engineering modeling, fusion-power-core mechanical design, neutronics analyses, and blanket thermalhydraulics studies are described. The approach, models, and interim results described here provide a basis for a more detailed design. Key issues quantified for the spherical-torus reactor center on the need for an efficient drive for this high-current (approx.40 MA) device as well as the economic desirability to increase the net electrical power from the nominal 500-MWe(net) value adopted for the baseline system. Although a direct extension of present tokamak scaling, the stablity and transport of this high-beta (approx.0.3) plasma is a key unknown that is resoluble only by experiment. The spherical torus generally provides a route to improved tokamak reactors as measured by considerably simplified coil technology in a configuration that allows a realistic magnetic divertor design, both leading to increased mass power density and reduced cost.

  17. A Design for Wind Lubrication of Hydraulic Lubrication Pump%一种用于风电润滑的液动润滑泵设计

    Institute of Scientific and Technical Information of China (English)

    周益; 臧铁钢; 高志朋; 雷晓光

    2012-01-01

    The design for a wind turbine hydraulic lubrication pump, this paper expounds the working principle, features and related function, this pump adopts hydraulic drive way, improve the lubrication pump outlet pressure, pumping performance and reliability. Finally, the control system design, realization sensing monitoring, automatic alarm, historical records and inquires the related functions.%设计了一种用于风力发电设备的液动润滑泵,阐述了其工作原理、主要特点以及相关功能.该泵采用液压方式驱动,提高了润滑泵的出口压力、泵送性能及可靠性.设计了控制系统,实现传感检测、自动报警、历史记录与查询等相关功能.

  18. On the reliability design of hydraulic structures%论水工建筑物的可靠性设计

    Institute of Scientific and Technical Information of China (English)

    陈厚群

    2013-01-01

    So far the application of the method of limit state method with partial factors to substitute the conventional single safety factor method has been disputed especially in the design circles of hydraulic structures,mainly because the former to be confused with reliability analysis.The single safety factor method involves both the non-random factor of engineering experience and all random uncertainties but without regard to their degree of uncertainty.The reliability analysis method can evaluate the combined failure probability of random uncertainties with different degrees but is unable to consider the factor of engineering experience which is now still important for design of hydraulic structures.In this paper some confused concepts inducing the debate are clarified.In the limit state method not only the different degrees of all random uncertainties can be distinguished by the partial factors,but also a structural factor γd is introduced to reflect the engineering experience.Obviously,it should be more logical than the conventional single safety factor method.At present,all the partial factors have still to be determined in accordance with the traditional safety factor in order to keep the continuous of the design codes.So,the concerned method is actually a multi-safety factor method having no essential difference with the conventional single safety factor method concerning the setting of safety level as a whole.However,it is entirely different from the reliability analysis method,as a structural factor γd is introduced and all partial factors both of action effects and resistances are determined independently from the reliability index.So,neither complex theory and unfamiliar terms nor insufficient statistical data must be worried about by the designers.Finally,as an example the successful application of the method of limit state method with partial factors in the《Seismic Design Code of Hydraulic Structures》is briefly described.%主要由于替代惯用的

  19. The Novel Design and Manufacturing Technology of Densified RDF from Reclaimed Landfill without a Mixing Binding Agent Using a Hydraulic Hot Pressing Machine

    Directory of Open Access Journals (Sweden)

    Kerdsuwan Somrat

    2016-01-01

    Full Text Available The manufacturing of RDF (Refuse Derived Fuel from a conventional cold press extrusion machine is not suitable for producing RDF from reclaimed landfill since it is not identical in shape and form after production due to the swelling of the plastic fraction contained inside the reclaimed landfill and hence needs a very high compression force. Moreover, a binder agent is needed in order to keep the RDF in a similar shape and form. A novel design and manufacturing technology for a hydraulic hot pressing machine has been established and can produce high-quality RDF without any binder. The two electrical heaters are installed at the inner core and on the surface of the mold. The compression force on the mold is performed by a hydraulic jack. In addition, a newly-designed locking plate system which is designed by a slider to open and close along the paired horizontal slots, can reduce the cycle time of the manufacturing process and yield higher productivity. The testing properties of the RDF produced by the novel hydraulic hot pressing machine include the examination of size, shape, weight, unit density, bulk density, compression strength, moisture content, and heating value. The results showed that the RDF is suitable to be used as feedstock in an incinerator or gasifier to produce green and clean energy from reclaimed landfill.

  20. 扒渣机液压系统设计与仿真分析%Design and Simulation of Hydraulic System for Cinder Scraper

    Institute of Scientific and Technical Information of China (English)

    杨林; 杨洋

    2013-01-01

    In order to meet the demands of the structure and functions,hydraulic system of the cinder scraper was designed on the basis of LUDV. Its simulation model was built,the simulation and analyses for the key components and the system static-dynamic per-formance were made. The results indicate that the designed hydraulic system is feasible and correct. It provides a basis for design and optimization of hydraulic system of the cinder scraper.%针对ZWY-120/55L型扒渣机结构组成及功能需求,进行了基于LUDV的扒渣机液压系统设计。利用AMESim模块化仿真平台,建立了扒渣机液压系统的仿真模型,并进行了关键部件和系统动静态性能的仿真与分析。仿真结果验证了液压系统的可行性和正确性,为扒渣机液压系统的设计与优化提供了依据。

  1. Technical considerations for designing low-cost, long-wave infrared objectives

    Science.gov (United States)

    Desroches, Gerard; Dalzell, Kristy; Robitaille, Blaise

    2014-06-01

    With the growth of uncooled infrared imaging in the consumer market, the balance between cost implications and performance criteria in the objective lens must be examined carefully. The increased availability of consumer-grade, long-wave infrared cameras is related to a decrease in military usage but it is also due to the decreasing costs of the cameras themselves. This has also driven up demand for low-cost, long-wave objectives that can resolve smaller pixels while maintaining high performance. Smaller pixels are traditionally associated with high cost objectives because of higher resolution requirements but, with careful consideration of all the requirements and proper selection of materials, costs can be moderated. This paper examines the cost/performance trade-off implications associated with optical and mechanical requirements of long-wave infrared objectives. Optical performance, f-number, field of view, distortion, focus range and thermal range all affect the cost of the objective. Because raw lens material cost is often the most expensive item in the construction, selection of the material as well as the shape of the lens while maintaining acceptable performance and cost targets were explored. As a result of these considerations, a low-cost, lightweight, well-performing objective was successfully designed, manufactured and tested.

  2. Some considerations for establishing seismic design criteria for nuclear plant piping

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.P. [Energy Technology Engineering Center, Canoga Park, CA (United States); Chokshi, N.C. [Nuclear Regulatory Commission, Washington, DC (United States)

    1997-01-01

    The Energy Technology Engineering Center (ETEC) is providing assistance to the U.S. NRC in developing regulatory positions on the seismic analysis of piping. As part of this effort, ETEC previously performed reviews of the ASME Code, Section III piping seismic design criteria as revised by the 1994 Addenda. These revised criteria were based on evaluations by the ASME Special Task Group on Integrated Piping Criteria (STGIPC) and the Technical Core Group (TCG) of the Advanced Reactor Corporation (ARC) of the earlier joint Electric Power Research Institute (EPRI)/NRC Piping & Fitting Dynamic Reliability (PFDR) program. Previous ETEC evaluations reported at the 23rd WRSM of seismic margins associated with the revised criteria are reviewed. These evaluations had concluded, in part, that although margins for the timed PFDR tests appeared acceptable (>2), margins in detuned tests could be unacceptable (<1). This conclusion was based primarily on margin reduction factors (MRFs) developed by the ASME STGIPC and ARC/TCG from realistic analyses of PFDR test 36. This paper reports more recent results including: (1) an approach developed for establishing appropriate seismic margins based on PRA considerations, (2) independent assessments of frequency effects on margins, (3) the development of margins based on failure mode considerations, and (4) the implications of Code Section III rules for Section XI.

  3. Carbon dioxide mineralization process design and evaluation: concepts, case studies, and considerations.

    Science.gov (United States)

    Yuen, Yeo Tze; Sharratt, Paul N; Jie, Bu

    2016-11-01

    Numerous carbon dioxide mineralization (CM) processes have been proposed to overcome the slow rate of natural weathering of silicate minerals. Ten of these proposals are mentioned in this article. The proposals are described in terms of the four major areas relating to CM process design: pre-treatment, purification, carbonation, and reagent recycling operations. Any known specifics based on probable or representative operating and reaction conditions are listed, and basic analysis of the strengths and shortcomings associated with the individual process designs are given in this article. The processes typically employ physical or chemical pseudo-catalytic methods to enhance the rate of carbon dioxide mineralization; however, both methods have its own associated advantages and problems. To examine the feasibility of a CM process, three key aspects should be included in the evaluation criteria: energy use, operational considerations as well as product value and economics. Recommendations regarding the optimal level of emphasis and implementation of measures to control these aspects are given, and these will depend very much on the desired process objectives. Ultimately, a mix-and-match approach to process design might be required to provide viable and economic proposals for CM processes.

  4. Consideration of neutral beam prompt loss in the design of a tokamak helicon antenna

    Energy Technology Data Exchange (ETDEWEB)

    Pace, D.C., E-mail: pacedc@fusion.gat.com; Van Zeeland, M.A.; Fishler, B.; Murphy, C.

    2016-11-15

    Highlights: • Neutral beam prompt losses place appreciable power on an in-vessel tokamak antenna. • Simulations predict prompt loss power and inform protective tile design. • Experiments confirm the validity of the prompt loss simulations. - Abstract: Neutral beam prompt losses (injected neutrals that ionize such that their first poloidal transit intersects with the wall) can put appreciable power on the outer wall of tokamaks, and this power may damage the wall or other internal components. These prompt losses are simulated including a protruding helicon antenna installation in the DIII-D tokamak and it is determined that 160 kW of power will impact the antenna during the injection of a particular neutral beam. Protective graphite tiles are designed in response to this modeling and the wall shape of the installed antenna is precisely measured to improve the accuracy of these calculations. Initial experiments confirm that the antenna component temperature increases according to the amount of neutral beam energy injected into the plasma. In this case, only injection of beams that are aimed counter to the plasma current produce an appreciable power load on the outer wall, suggesting that the effect is of little concern for tokamaks featuring only co-current neutral beam injection. Incorporating neutral beam prompt loss considerations into the design of this in-vessel component serves to ensure that adequate protection or cooling is provided.

  5. Bioequivalence study designs for generic solid oral anticancer drug products: scientific and regulatory considerations.

    Science.gov (United States)

    Kaur, Paramjeet; Chaurasia, Chandra S; Davit, Barbara M; Conner, Dale P

    2013-12-01

    The demonstration of bioequivalence (BE) between the test and reference products is an integral part of generic drug approval process. A sound BE study design is pivotal to the successful demonstration of BE of generic drugs to their corresponding reference listed drug product. Generally, BE of systemically acting oral dosage forms is demonstrated in a crossover, single-dose in vivo study in healthy subjects. The determination of BE of solid oral anticancer drug products is associated with its own unique challenges due to the serious safety risks involved. Unlike typical BE study in healthy subjects, the safety issues often necessitate conducting BE studies in cancer patients. Such BE studies of an anticancer drug should be conducted without disturbing the patients' therapeutic dosing regimen. Attributes such as drug permeability and solubility, pharmacokinetics, dosing regimen, and approved therapeutic indication(s) are considered in the BE study design of solid anticancer drug products. To streamline the drug approval process, the Division of Bioequivalence posts the Bioequivalence Recommendations for Specific Products guidances on the FDA public website. The objective of this article is to illustrate the scientific and regulatory considerations in the design of BE studies for generic solid oral anticancer drug products through examples.

  6. Facts learnt from the Hanshin-Awaji disaster and consideration on design basis earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Heki [Yokohama National Univ. (Japan). Faculty of Engineering

    1997-03-01

    This paper will deal with how to establish the concept of the design basis earthquake for critical industrial facilities such as nuclear power plants in consideration of disasters induced by the 1995 Hyogoken-Nanbu Earthquake (Southern Hyogo-prefecture Earthquake-1995), so-called Kobe earthquake. The author once discussed various DBEs at 7 WCEE. At that time, the author assumed that the strongest effective PGA would be 0.7 G, and compared to the values of accelerations to a structure obtained by various codes in Japan and other countries. The maximum PGA observed by an instrument at the Southern Hyogo-pref. Earthquake-1995 exceeded the previous assumption of the author, even though the evaluation results of the previous paper had been pessimistic. According to the experience of Kobe event, the author will point out the necessity of the third earthquake S{sub s} adding to S{sub 1} and S{sub 2}, previous DBEs. (author)

  7. BPM Design and Impedance Considerations for a Rotatable Collimator for the LHC Collimation Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jeffrey Claiborne; /SLAC; Keller, Lewis; /SLAC; Lundgren, Steven; /SLAC; Markiewicz, Thomas; /SLAC; Young, Andrew; /SLAC

    2010-08-26

    The Phase II upgrade to the LHC collimation system calls for complementing the 30 high robust Phase I graphite secondary collimators with 30 high Z Phase II collimators. This paper reports on BPM and impedance considerations and measurements of the integrated BPMs in the prototype rotatable collimator to be installed in the Super Proton Synchrotron (SPS) at CERN. The BPMs are necessary to align the jaws with the beam. Without careful design the beam impedance can result in unacceptable heating of the chamber wall or beam instabilities. The impedance measurements involve utilizing both a single displaced wire and two wires excited in opposite phase to disentangle the driving and detuning transverse impedances. Trapped mode resonances and longitudinal impedance are to also be measured and compared with simulations. These measurements, when completed, will demonstrate the device is fully operational and has the impedance characteristics and BPM performance acceptable for installation in the SPS.

  8. Integrated design and evaluation of biomass energy system taking into consideration demand side characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Hongbo [Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 56-1 Toji-in Kitamachi, Kita-Ku, 603-8577 Kyoto (Japan); Zhou, Weisheng; Nakagami, Ken' ichi [College of Policy Sciences, Ritsumeikan University, 603-8577 Kyoto (Japan); Gao, Weijun [Faculty of Environmental Engineering, The University of Kitakyushu, 808-0135 Kitakyushu (Japan)

    2010-05-15

    In this paper, a linear programming model has been developed for the design and evaluation of biomass energy system, while taking into consideration demand side characteristics. The objective function to be minimized is the total annual cost of the energy system for a given customer equipped with a biomass combined cooling, heating and power (CCHP) plant, as well as a backup boiler fueled by city gas. The results obtained from the implementation of the model demonstrate the optimal system capacities that customers could employ given their electrical and thermal demands. As an illustrative example, an investigation addresses the optimal biomass CCHP system for a residential area located in Kitakyushu Science and Research Park, Japan. In addition, sensitivity analyses have been elaborated in order to show how the optimal solutions would vary due to changes of some key parameters including electricity and city gas tariffs, biogas price, electricity buy-back price, as well as carbon tax rate. (author)

  9. System considerations and RF front-end design for integration of satellite navigation and mobile standards

    Directory of Open Access Journals (Sweden)

    A. Miskiewicz

    2009-05-01

    Full Text Available The paper presents the challenges involved in a system design of a robust reconfigurable RF front-end for navigation and mobile standards. Receiver architecture is chosen from the point of view of inter-system interference and 130nm CMOS process characteristics. System concept covers the implementation of GPS, Galileo, UMTS, GSM and CDMA2000 using a Zero-IF architecture with reconfigurable analog and digital path. Feasibility studies of the system cover analysis of the wireless regulations and performance criteria, such as overall gain, noise figure (NF, and 1dB compression point (P1dB of the RF chain, phase noise requirements and VCO tuning range [1]. The presented chip was fabricated in 130 nm CMOS technology. System considerations are confirmed with the chip measurements of gain, noise figure, and linearity. Prospects for the future work are presented including technology shrink.

  10. 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…

  11. 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...

  12. Design Considerations for Attitude State Awareness and Prevention of Entry into Unusual Attitudes

    Science.gov (United States)

    Ellis, Kyle K. E.; Prinzel, Lawrence J., III; Arthur, Jarvis J.; Nicholas, Stephanie N.; Kiggins, Daniel; Verstynen, Harry; Hubbs, Clay; Wilkerson, James

    2017-01-01

    Loss of control - inflight (LOC-I) has historically represented the largest category of commercial aviation fatal accidents. A review of the worldwide transport airplane accidents (2001-2010) evinced that loss of attitude or energy state awareness was responsible for a large majority of the LOC-I events. A Commercial Aviation Safety Team (CAST) study of 18 worldwide loss-of-control accidents and incidents determined that flight crew loss of attitude awareness or energy state awareness due to lack of external visual reference cues was a significant causal factor in 17 of the 18 reviewed flights. CAST recommended that "Virtual Day-Visual Meteorological Condition" (Virtual Day-VMC) displays be developed to provide the visual cues necessary to prevent loss-of-control resulting from flight crew spatial disorientation and loss of energy state awareness. Synthetic vision or equivalent systems (SVS) were identified for a design "safety enhancement" (SE-200). Part of this SE involves the conduct of research for developing minimum aviation system performance standards (MASPS) for these flight deck display technologies to aid flight crew attitude and energy state awareness similar to that of a virtual day-VMC-like environment. This paper will describe a novel experimental approach to evaluating a flight crew's ability to maintain attitude awareness and to prevent entry into unusual attitudes across several SVS optical flow design considerations. Flight crews were subjected to compound-event scenarios designed to elicit channelized attention and startle/surprise within the crew. These high-fidelity scenarios, designed from real-world events, enable evaluation of the efficacy of SVS at improving flight crew attitude awareness to reduce the occurrence of LOC-I incidents in commercial flight operations.

  13. Design considerations for massively parallel sequencing studies of complex human disease.

    Directory of Open Access Journals (Sweden)

    Bing-Jian Feng

    Full Text Available Massively Parallel Sequencing (MPS allows sequencing of entire exomes and genomes to now be done at reasonable cost, and its utility for identifying genes responsible for rare Mendelian disorders has been demonstrated. However, for a complex disease, study designs need to accommodate substantial degrees of locus, allelic, and phenotypic heterogeneity, as well as complex relationships between genotype and phenotype. Such considerations include careful selection of samples for sequencing and a well-developed strategy for identifying the few "true" disease susceptibility genes from among the many irrelevant genes that will be found to harbor rare variants. To examine these issues we have performed simulation-based analyses in order to compare several strategies for MPS sequencing in complex disease. Factors examined include genetic architecture, sample size, number and relationship of individuals selected for sequencing, and a variety of filters based on variant type, multiple observations of genes and concordance of genetic variants within pedigrees. A two-stage design was assumed where genes from the MPS analysis of high-risk families are evaluated in a secondary screening phase of a larger set of probands with more modest family histories. Designs were evaluated using a cost function that assumes the cost of sequencing the whole exome is 400 times that of sequencing a single candidate gene. Results indicate that while requiring variants to be identified in multiple pedigrees and/or in multiple individuals in the same pedigree are effective strategies for reducing false positives, there is a danger of over-filtering so that most true susceptibility genes are missed. In most cases, sequencing more than two individuals per pedigree results in reduced power without any benefit in terms of reduced overall cost. Further, our results suggest that although no single strategy is optimal, simulations can provide important guidelines for study design.

  14. 双向液压锁新型车载液压尾板系统的研究与设计%Research and Design of A New Type of Vehicle Hydraulic Lift-tail System Using Hydraulic Lock

    Institute of Scientific and Technical Information of China (English)

    赵丽华; 李喜玲; 高和平

    2016-01-01

    车载液压尾板在现代汽车装载作业中被广泛应用。由于汽车车底空间有限,不能承受太大的重量,所以整个液压尾板的尺寸与重量成为尾板设计过程中首先要考虑的问题。现在市面上大部分液压尾板采用两个举升油缸、两个翻转油缸和一个平衡油缸的结构型式控制尾板的举升与翻转,油缸较多,使整个尾板的重量增加,且传动结构复杂。本文将介绍一种新式液压尾板设计思路,省去平衡缸,且举升缸和翻转缸分别用一个,举升缸采用二级伸缩油缸控制尾板的翻转与举升,液压系统中加装液压锁。该传动机构简单实用,在减小了尾板尺寸与重量的同时,提升了整套设备的安全性与可靠性。%Vehicle hydraulic lift-tail has been applied in the truck loading operation . Due to the space of the car’s bottom is limited,it can’t bear too much,so the size and weight of the hydraulic lift-tail become the first issue to be consided in the process of design. Now on the market,most of the hydraulic lift-tail works with two lifting oil cylinder, two overturning oil cylinder and one balance cylinder to f control the lift-tail’s lifting and overturning, cylinder is too many, make the whole weight of the lift-tail increase,and the transmission structure is too complex. This paper will introduce a new design of the hydraulic lift-tail,save the balance cylinder,only use one lifting cylinder and one overturning cylinder, and use the secondary scaling cylinder to control the overturning and lifting of the lift-tail ,the transmission mechanism is simple and practical ,in this way,it can achieve the purpose of reducing the size and weight of the hydraulic lift-tail and improving the security and reliability of the whole equipment.

  15. Design of Hydraulic System for the LTQ-2000Y Passenger Boarding Bridge%LTQ-2000Y型旅客登机桥液压系统设计

    Institute of Scientific and Technical Information of China (English)

    郭会歌; 薛鹏; 杨军宁; 王永利

    2012-01-01

    阐述了旅客登机桥的作用及对液压系统的要求.介绍了LTQ-2000Y型旅客登机桥的液压系统的设计实践,包括油源系统、升降回路、行走回路、转向回路、调平回路、回转回路和应急回路的设计.归纳了该液压系统的主要特点:控制、操作方式多样;油源高效、节能;行走、制动可靠;升降同步、可控;调平自动、及时.这些特点在设备使用中得到了良好的体现.%The passenger boarding bridge's function and its requirement to the hydraulic system were expatiated. The design practices of the LTQ-2000Y passenger boarding bridge's hydraulic system were described, including the design of the oil source system, lifting loop, walking loop, steering loop, leveling loop, rotating loop and emergency loop. The main features of the hydraulic system were generalized; the control and operation modes were varied; oil source was efficient and energy-saving; walking and braking was reliable; up & down lifting was synchronized and controllable; leveling was automatically and timely. These features are well reflected when using the device.

  16. 液压泵性能检测实验台设计及检测分析%Design of Performance Test System for Hydraulic Pump

    Institute of Scientific and Technical Information of China (English)

    武金良; 赵坚; 于浩

    2016-01-01

    液压泵是液压系统中的动力元件,其性能的优劣直接影响到液压系统的工作。因此,对其进行性能检测十分必要。引入绿色设计理念,设计了液压泵性能检测系统,并进行了实测验证,保证了系统检测数据的精度,提高了检测效率。%The hydraulic pump is the drive component of the hydraulic system, its performance will directly affect the normal work of hydraulic system. Therefore, it is very necessary to test its performance. The concept of green design was introduced, the hy⁃draulic pump performance test system was designed, and the verification was completed. So the accuracy of the system is guaranteed, and its detecting efficiency is improved obviously.

  17. 无液压缸驱动的压力机设计探讨%Design discussion about forging press without hydraulic cylinder driving system

    Institute of Scientific and Technical Information of China (English)

    黄家仕; 陆红

    2013-01-01

    The feasibility of forging prebs without hydraulic cylinder driving system has been demonstrated in the text from many aspects. As the seal failure of the hydraulic cylinder has caused the leak of liquid, the advantages of application of machinery and hydraulic without cylinder driving has been described. The design of press without cylinder technology is the best idea for environment-protective design and cost.%对于无液压缸驱动滑块的锻压液压机,从诸多方面进行了较为全面的可行性论证.以液压缸密封不良而导致液体的泄漏为主线,说明无缸驱动是各种相关机电液技术综合应用的极致.在规避了液压机研发关键性技术短板的前提下,无缸乃是液压机实现绿色设计与低碳运行的最佳构思.

  18. Using observed postconstruction peak discharges to evaluate a hydrologic and hydraulic design model, Boneyard Creek, Champaign and Urbana, Illinois

    Science.gov (United States)

    Over, Thomas M.; Soong, David T.; Holmes, Jr., Robert R.

    2011-01-01

    Boneyard Creek—which drains an urbanized watershed in the cities of Champaign and Urbana, Illinois, including part of the University of Illinois at Urbana-Champaign (UIUC) campus—has historically been prone to flooding. Using the Stormwater Management Model (SWMM), a hydrologic and hydraulic model of Boneyard Creek was developed for the design of the projects making up the first phase of a long-term plan for flood control on Boneyard Creek, and the construction of the projects was completed in May 2003. The U.S. Geological Survey, in cooperation with the Cities of Champaign and Urbana and UIUC, installed and operated stream and rain gages in order to obtain data for evaluation of the design-model simulations. In this study, design-model simulations were evaluated by using observed postconstruction precipitation and peak-discharge data. Between May 2003 and September 2008, five high-flow events on Boneyard Creek satisfied the study criterion. The five events were simulated with the design model by using observed precipitation. The simulations were run with two different values of the parameter controlling the soil moisture at the beginning of the storms and two different ways of spatially distributing the precipitation, making a total of four simulation scenarios. The simulated and observed peak discharges and stages were compared at gaged locations along the Creek. The discharge at one of these locations was deemed to be critical for evaluating the design model. The uncertainty of the measured peak discharge was also estimated at the critical location with a method based on linear regression of the stage and discharge relation, an estimate of the uncertainty of the acoustic Doppler velocity meter measurements, and the uncertainty of the stage measurements. For four of the five events, the simulated peak discharges lie within the 95-percent confidence interval of the observed peak discharges at the critical location; the fifth was just outside the upper end of

  19. Using observed postconstruction peak discharges to evaluate a hydrologic and hydraulic design model, Boneyard Creek, Champaign and Urbana, Illinois

    Science.gov (United States)

    Over, Thomas M.; Soong, David T.; Holmes, Jr., Robert R.

    2011-01-01

    Boneyard Creek—which drains an urbanized watershed in the cities of Champaign and Urbana, Illinois, including part of the University of Illinois at Urbana-Champaign (UIUC) campus—has historically been prone to flooding. Using the Stormwater Management Model (SWMM), a hydrologic and hydraulic model of Boneyard Creek was developed for the design of the projects making up the first phase of a long-term plan for flood control on Boneyard Creek, and the construction of the projects was completed in May 2003. The U.S. Geological Survey, in cooperation with the Cities of Champaign and Urbana and UIUC, installed and operated stream and rain gages in order to obtain data for evaluation of the design-model simulations. In this study, design-model simulations were evaluated by using observed postconstruction precipitation and peak-discharge data. Between May 2003 and September 2008, five high-flow events on Boneyard Creek satisfied the study criterion. The five events were simulated with the design model by using observed precipitation. The simulations were run with two different values of the parameter controlling the soil moisture at the beginning of the storms and two different ways of spatially distributing the precipitation, making a total of four simulation scenarios. The simulated and observed peak discharges and stages were compared at gaged locations along the Creek. The discharge at one of these locations was deemed to be critical for evaluating the design model. The uncertainty of the measured peak discharge was also estimated at the critical location with a method based on linear regression of the stage and discharge relation, an estimate of the uncertainty of the acoustic Doppler velocity meter measurements, and the uncertainty of the stage measurements. For four of the five events, the simulated peak discharges lie within the 95-percent confidence interval of the observed peak discharges at the critical location; the fifth was just outside the upper end of

  20. Design considerations for remotely operated welding in space: Task definition and visual weld monitoring experiment

    Science.gov (United States)

    Reynerson, Charles M.

    1993-05-01

    This thesis explores the concept of welding in a space environment with the use of automation. Since the amount of time astronauts can work outside a spacecraft is limited, future construction and repair tasks will likely be assisted by automation. It is also likely that remote space welding will be needed for the construction of large-scale space structures in earth orbit as well as for lunar and Martian ground-based structures. Due to the complex nature of the tasks to be accomplished, the equipment will probably not be fully autonomous but instead supervised by a human operator. The welding fabrication problem in space is examined in a broad sense including some of the considerations for designing a human supervisory remote welding system. The history of space welding processes is examined, as well as current research in the field. A task definition and functional analysis is provided to assist future designers in outlining typical operational sequences for such a remote welding system. Such analysis is important when deciding whether the human operator should perform certain tasks or if the operator should supervise the automated system while it performs the tasks.

  1. Design considerations and experimental results for MRI systems using HTS magnets

    Science.gov (United States)

    Parkinson, Ben

    2017-01-01

    An increasing number of magnetic resonance imaging (MRI) systems using high temperature superconductors (HTS) magnets have been designed and constructed, with detailed results of their performance now available. Features of REBCO and BSCCO conductors are described as they pertain to use in high homogeneity magnets, with emphasis placed on the practical use of these conductors in magnets. Methods of coil winding are discussed, in particular the differences between pancake and layer winding techniques. Design considerations for HTS magnets are presented in light of the difficulties presented by quench in these magnets, but also in terms of the features of HTS magnets afforded by their high operating temperatures, namely robust cryogen free operation and the potential to use unshielded gradient coils. Drawing on two example MRI systems, namely a 3 T BSCCO brain imaging magnet developed in Japan and a 1.5 T REBCO orthopaedic imaging system developed in New Zealand, the report details real-world stability and homogeneity of HTS-MRI systems, in particular with regards to the screening current effects observed in these systems. It is concluded that, apart from conductor cost, there are currently no technical obstacles to use of HTS-MRI systems.

  2. 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.

  3. 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...

  4. 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.

  5. A geostatistical methodology for the optimal design of space-time hydraulic head monitoring networks and its application to the Valle de Querétaro aquifer.

    Science.gov (United States)

    Júnez-Ferreira, H E; Herrera, G S

    2013-04-01

    This paper presents a new methodology for the optimal design of space-time hydraulic head monitoring networks and its application to the Valle de Querétaro aquifer in Mexico. The selection of the space-time monitoring points is done using a static Kalman filter combined with a sequential optimization method. The Kalman filter requires as input a space-time covariance matrix, which is derived from a geostatistical analysis. A sequential optimization method that selects the space-time point that minimizes a function of the variance, in each step, is used. We demonstrate the methodology applying it to the redesign of the hydraulic head monitoring network of the Valle de Querétaro aquifer with the objective of selecting from a set of monitoring positions and times, those that minimize the spatiotemporal redundancy. The database for the geostatistical space-time analysis corresponds to information of 273 wells located within the aquifer for the period 1970-2007. A total of 1,435 hydraulic head data were used to construct the experimental space-time variogram. The results show that from the existing monitoring program that consists of 418 space-time monitoring points, only 178 are not redundant. The implied reduction of monitoring costs was possible because the proposed method is successful in propagating information in space and time.

  6. 基于PLC的液压驱动式机械手动作设计%The Movement Design of Hydraulic Manipulator Based on PLC

    Institute of Scientific and Technical Information of China (English)

    朱凌宏

    2011-01-01

    A kind of hydraulic manipulator was introduced. The traits includled simple configuration and balanced movement. It was fit for conveying heavy objects. By analyzing the movement process, the hydraulic loop was designed, simulation and movement control based on PLC were completed. A simulated expriment was done on YZ-02 fluid driving platform. The results show that the hydraulic manipulator has strong power and stable performamce. The used differential loop improve local velocity.%介绍一款采用液压驱动式的机械手,该机械手的特点是结构简单、输出力大、动作平稳,适合于大物件的搬运工作.针对该机械手各动作情况分别对其进行液压回路设计、模拟仿真、PIE顺序控制,并在YZ-02型智能化液压传动实验台上进行机电液一体化模拟实验.实验结果表明:液压驱动式机械手抓力较大,工作性能稳定,通过差动回路可改善其局部运行速度.

  7. 摇摆台升沉运动液压系统设计%Design of Hydraulic Lift System for Swing Bench

    Institute of Scientific and Technical Information of China (English)

    张瑜; 王红艳; 沈延康; 田魁岳; 鲁士军

    2012-01-01

    This swing bench(oscillating table) is a precise piece of equipment for physical simulation that it can simulate a boat oscillating under various sea water conditions. The text introduces how the up-down motion hydraulic system was designed for the oscillating table, and how to analyze the oil-pneumatic spring-balance system and the hydraulic servo system which was consisted of bag-type accumulator and hydraulic cylinders while pointing out superiorities of the system's minimized inertial impact, lower power drive rate, and lower cost.%摇摆试验台(摇摆台)是一种高精度物理仿真设备,它可以模拟舰船在不同海况下的摇摆运动.介绍摇摆台的升沉运动液压系统的设计,对囊式蓄能器和液压缸组成的油气弹簧平衡系统和液压伺服系统进行分析.指出此系统在减小惯性冲击,降低系统驱动功率,降低成本方面的优势.

  8. Launch and Functional Considerations Guiding the Scaling and Design of Rigid Inflatable Habitat Modules

    Science.gov (United States)

    Bell, L.

    2002-01-01

    The Sasakawa International Center for Space Architecture (SICSA) has a long history of projects that involve design of space structures, including habitats for low-Earth orbit (LEO) and planetary applications. Most of these facilities and component systems are planned to comply with size, geometry and mass restrictions imposed by the Space Shuttle Orbiter's payload and lift/landing abort restrictions. These constraints limit launch elements to approximately 15 ft. diameter, 40 ft. long cylindrical dimensions weighing no more than approximately 25 metric tons. It is clear that future success of commercial space programs such as tourism will hinge upon the availability of bigger and more efficient Earth to LEO launch vehicles which can greatly reduce transportation and operational costs. This will enable development and utilization of larger habitat modules and other infrastructure elements which can be deployed with fewer launches and on-orbit assembly procedures. The sizing of these new heavy lift launchers should be scaled to optimize habitat functionality and efficiency, just as the habitat designs must consider optimization of launch vehicle economy. SICSA's planning studies address these vehicle and habitat optimization priorities as parallel and interdependent considerations. The allowable diameter of habitat modules established by launch vehicle capacity dictates functionally acceptable internal configuration options. Analyses of these options relative to practical dimensions for Earth-to-orbit launch vehicle scaling were conducted for two general schemes. The "bologna slice" configuration stacks the floors within a predominately cylindrical or spherical envelope, producing circular areas. The "banana split" approach divides a cylindrical module longitudinally, creating floors that are generally rectangular in shape. The assessments established minimum sizes for reasonable utility and efficiency. The bologna slice option. This configuration is only acceptable

  9. Design Considerations for the Nuclear Thermal Rocket Element Environmental Simulator (NTREES)

    Science.gov (United States)

    Emrich, Bill; Kirk, Daniel

    2006-01-01

    Nuclear Thermal Rockets or NTR's have been suggested as a propulsion system option for vehicles traveling to the moon or Mars. These engines are capable of providing high thrust at specific impulses at least twice that of today s best chemical engines. The performance constraints on these engines are mainly the result of temperature limitations on the fuel coupled with a limited ability to withstand chemical attack by the hot hydrogen propellant. To operate at maximum efficiency, fuel forms are desired which can withstand the extremely hot, hostile environment characteristic of NTR operation for at least several hours. The simulation of such an environment would require an experimental device which could simultaneously approximate the power, flow, and temperature conditions which a nuclear fuel element (or partial element) would encounter during NTR operation. Such a simulation would allow detailed studies of the fuel behavior and hydrogen flow characteristics under reactor like conditions to be performed. The goal of these simulations would be directed toward expanding the performance envelope of NTR engines over that which was demonstrated during the Rover and NERVA nuclear rocket programs of the 1970's. Currently, such a simulator is nearing completion at the Marshall Space Flight Center, and will shortly be used in the future to evaluate a wide variety of he1 element designs and the materials of which they are constructed. This present work addresses the initial experimental objectives of the Nuclear Thermal Rocket Element Environmental Simulator or NTREES and some of the design considerations which were considered prior to and during its construction.

  10. The SpeX Prism Library Analysis Toolkit: Design Considerations and First Results

    Science.gov (United States)

    Burgasser, Adam J.; Aganze, Christian; Escala, Ivana; Lopez, Mike; Choban, Caleb; Jin, Yuhui; Iyer, Aishwarya; Tallis, Melisa; Suarez, Adrian; Sahi, Maitrayee

    2016-01-01

    Various observational and theoretical spectral libraries now exist for galaxies, stars, planets and other objects, which have proven useful for classification, interpretation, simulation and model development. Effective use of these libraries relies on analysis tools, which are often left to users to develop. In this poster, we describe a program to develop a combined spectral data repository and Python-based analysis toolkit for low-resolution spectra of very low mass dwarfs (late M, L and T dwarfs), which enables visualization, spectral index analysis, classification, atmosphere model comparison, and binary modeling for nearly 2000 library spectra and user-submitted data. The SpeX Prism Library Analysis Toolkit (SPLAT) is being constructed as a collaborative, student-centered, learning-through-research model with high school, undergraduate and graduate students and regional science teachers, who populate the database and build the analysis tools through quarterly challenge exercises and summer research projects. In this poster, I describe the design considerations of the toolkit, its current status and development plan, and report the first published results led by undergraduate students. The combined data and analysis tools are ideal for characterizing cool stellar and exoplanetary atmospheres (including direct exoplanetary spectra observations by Gemini/GPI, VLT/SPHERE, and JWST), and the toolkit design can be readily adapted for other spectral datasets as well.This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. NNX15AI75G. SPLAT code can be found at https://github.com/aburgasser/splat.

  11. CONSIDERATIONS REGARDING THE DESIGN OF FOOTWEAR WHICH ASSURES THE HEALTH OF THE FOOT

    Directory of Open Access Journals (Sweden)

    MĂRCUŞ Liviu

    2016-05-01

    Full Text Available The high demands for cheap footwear can only be satisfied by mass fabrication. Costumed footwear would represent a regress, despite the advantages that it brings. This paper regards mainly the demands that mass footwear requires, in order to maintain the health of the foot. The desire to maintain the foot shape and functionality requires certain last forms and fabrication algorithms. We analyze certain aspects referring to: the correct design of the inner sole, insuring the flexibility of the lower part of the footwear by choosing the right type of materials and confection systems, choosing the right height of the heel, setting the adequate shape by increasing the number of different shoe sizes. In order to give a loose space to the adults’ toes, where they are not pressed, but have a complete range of motion, the orthopedists and the last specialists have set several requirements for building the contour of the inner sole. The technique of building a bond between the footwear forepart and the inferior ensemble is dependent to the purpose and partially to the fashion demands of the shoe. The sole shape is influenced by the buyers, as seen by the development of the ex-flex footwear. There must be noted that in this case, the work of the model designer coincides with the exigencies of the specialist in footwear health. With the help of certain functional considerations and of several mechanical calculations, it can be proven that a heel with a height of 3 cm does not necessarily have a negative impact on the foot health. This is why even the orthopedics consider this limit as acceptable. Higher heels must be avoided if we want to maintain a normal function and development of the foot.

  12. Design consideration for nano-accuracy long trace profiler at BSRF

    Science.gov (United States)

    Yang, Fugui; Wang, Lichao; Tang, Shanzhi; Wang, Qiushi; Li, Ming

    2014-09-01

    The third generation synchrotron radiation source like High Energy Photon Source (HEPS, Beijing) requires X-ray optics surface with high accuracy. It is crucial to develop advanced optics surface metrology instrument. The Long Trace Profiler (LTP) is an instrument which measures slope in the long dimension of an optical surface. In order to meet the accuracy requirements for synchrotron optics, a number of researches have been carried out to improve the LTP during the last decades. Many variations have been installed worldwide. As a part of the advanced research of HEPS, the metrology laboratory at Beijing Synchrotron Radiation Facility (BSRF, Beijing) has been conducting work of building a new LTP since 2012. The accuracy of the instrument is expected to be <0.1μrad rms for component up to 1m in length. In this paper, we present some design consideration for nano-accuracy LTP. Two error sources, including the deformation of the granite structure and imperfect optical surface, are studied. We report our optimized configuration of the granite structure and the dependences of the measurement error on the surface error. The results are considered as an important instruction for the proper choice of each component in the profiler. We expect to bring the profiler into operation in 2015.

  13. Antibiotic-free selection in E. coli: new considerations for optimal design and improved production

    Directory of Open Access Journals (Sweden)

    Peubez Isabelle

    2010-09-01

    Full Text Available Abstract Background The increasing regulatory requirements to which biological agents are subjected will have a great impact in the field of industrial protein expression and production. There is an expectation that in a near future, there may be "zero tolerance" towards antibiotic-based selection and production systems. Besides the antibiotic itself, the antibiotic resistance gene is an important consideration. The complete absence of antibiotic-resistance gene being the only way to ensure that there is no propagation in the environment or transfer of resistance to pathogenic strains. Results In a first step, we have designed a series of vectors, containing a stabilization element allowing a complete elimination of antibiotics during fermentation. Vectors were further improved in order to include alternative selection means such as the well known poison/antidote stabilization system. Eventually we propose an elegant positive pressure of selection ensuring the elimination of the antibiotic-resistance gene through homologous recombination. In addition, we have shown that the presence of an antibiotic resistance gene can indirectly reduce the amount of expressed protein, since even in absence of selection pressure the gene would be transcribed and account for an additional stress for the host during the fermentation process. Conclusions We propose a general strategy combining plasmid stabilization and antibiotic-free selection. The proposed host/vector system, completely devoid of antibiotic resistance gene at the end of construction, has the additional advantage of improving recombinant protein expression and/or plasmid recovery.

  14. Human engineering design considerations for the use of signal color enhancement in ASW displays

    Energy Technology Data Exchange (ETDEWEB)

    Banks, W.W.

    1990-11-01

    The Lawrence Livermore National Laboratory (LLNL) was requested to examine and define man-machine limits as part of the Office of Naval Technology's High Gain Initiative program (HGI). As an initial investigative area, LLNL's Systems and Human Performance effort focused upon color display interfaces and the use of color enhancement techniques to define human and system interface limits in signal detection and discrimination tasks. The knowledgeable and prudent use of color in different types of display is believed to facilitate human visual detection, discrimination and recognition in complex visual tasks. The consideration and understanding of the complex set of interacting variables associated with the prudent use of color is essential to optimize human performance, especially in the ASW community. The designers of advanced display technology and signal processing algorithms may be eventually called upon to present pre-processed information to ASW operators and researchers using the latest color enhancement techniques. These techniques, however, may be limited if one does not understand the complexity and limits of human information processing which reflects the assessed state of knowledge relevant to the use of color in displays. The initial sections of this report discuss various aspects of color presentation and the problems typically encountered, while the last section deals with a specific research proposal required to further our understanding and proper use of color enhancement methods.

  15. Beyond Mouse and Keyboard: Expanding Design Considerations for Information Visualization Interactions.

    Science.gov (United States)

    Lee, Bongshin; Isenberg, P; Riche, N H; Carpendale, S

    2012-12-01

    The importance of interaction to Information Visualization (InfoVis) and, in particular, of the interplay between interactivity and cognition is widely recognized [12, 15, 32, 55, 70]. This interplay, combined with the demands from increasingly large and complex datasets, is driving the increased significance of interaction in InfoVis. In parallel, there have been rapid advances in many facets of interaction technologies. However, InfoVis interactions have yet to take full advantage of these new possibilities in interaction technologies, as they largely still employ the traditional desktop, mouse, and keyboard setup of WIMP (Windows, Icons, Menus, and a Pointer) interfaces. In this paper, we reflect more broadly about the role of more "natural" interactions for InfoVis and provide opportunities for future research. We discuss and relate general HCI interaction models to existing InfoVis interaction classifications by looking at interactions from a novel angle, taking into account the entire spectrum of interactions. Our discussion of InfoVis-specific interaction design considerations helps us identify a series of underexplored attributes of interaction that can lead to new, more "natural," interaction techniques for InfoVis.

  16. Design considerations regarding slug ruptures in the intermediate power level reactor

    Energy Technology Data Exchange (ETDEWEB)

    Pearl, W.L.; Pursel, C.A.

    1954-11-01

    The minimum shutdown time, to permit accessibility, for the Intermediate Power Reactor is estimated to be 38 hours. In case the reactor were shutdown following each rupture this long shutdown period would have serious disadvantages. The desirability of being able to make firm power commitments (independent of slug ruptures) has led to a study of the possibility of continuous operation following a rupture. There is evidence to indicate that, at the proposed water temperature, the rate of corrosion of uranium may be so high that at least a major portion of the rupture products may have entered the system before the reactor can be shutdown. A pushout of the affected column would then be a pushout of only those slugs which are still intact and the problem would still remain of removing the rupture products from the system. The first portion of this report is concerned with the rate of corrosion of a slug following rupture and the possible limitations to the principle of non-shutdown operation. These limitations include a flow stoppage by the ruptured can, undue increase in gamma activity, increased corrosion by the rupture products, and adherence of rupture products to the piping. The latter portion of the document is concerned with design considerations of the shielding and water plant so as to eliminate or minimize the effects of the introduction of rupture products into the cooling system. 7 refs., 2 figs.

  17. 一种同构式主从液压机械手的设计%Design of an Isomorphism Type Master-slave Hydraulic Manipulator

    Institute of Scientific and Technical Information of China (English)

    张丽

    2015-01-01

    提出一种同构式主从液压机械手, 应用直线型光栅作为主手位置的检测装置、 应用步进式电动推杆驱动从手,设计了新型液压传动装置并用此液压装置传递动力, 主手的直线型光栅发出的脉冲经硬件电路处理后, 直接作为步进式电动推杆的驱动与控制脉冲, 步进式电动推杆经液压传动装置把运动传递给机械手的从手, 从手可完全、 实时重复主手的动作.%An isomorphism type master-slave hydraulic manipulator was presented. Applying linear grating as the main hand posi-tion detecting device, applying stepping type electric push rod to drive the slave hand, a new type of hydraulic transmission was designed and the hydraulic device was used to transfer power. The pulses generated by master hand linear grating were processed by the hardware circuit, then they were directly as the control pulses of the stepping electric push rod. Through hydraulic transmission device, the stepping electric push rod transferred the motion to the slave hand, so the slave hand could completely repeat the movements of the main hand real-time.

  18. 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.

  19. Design and hydraulic characteristics of a field-scale bi-phasic bioretention rain garden system for storm water management.

    Science.gov (United States)

    Yang, H; Florence, D C; McCoy, E L; Dick, W A; Grewal, P S

    2009-01-01

    A field-scale bioretention rain garden system was constructed using a novel bi-phasic (i.e. sequence of anaerobic to aerobic) concept for improving retention and removal of storm water runoff pollutants. Hydraulic tests with bromide tracer and simulated runoff pollutants (nitrate-N, phosphate-P, Cu, Pb, and Zn) were performed in the system under a simulated continuous rainfall. The objectives of the tests were (1) to determine hydraulic characteristics of the system, and (2) to evaluate the movement of runoff pollutants through the system. For the 180 mm/24 h rainfall, the bi-phasic bioretention system effectively reduced both peak flow (approximately 70%) and runoff volume (approximately 42%). The breakthrough curves (BTCs) of bromide tracer suggest that the transport pattern of the system is similar to dispersed plug flow under this large runoff event. The BTCs of bromide showed mean 10% and 90% breakthrough times of 5.7 h and 12.5 h, respectively. Under the continuous rainfall, a significantly different transport pattern was found between each runoff pollutant. Nitrate-N was easily transported through the system with potential leaching risk from the initial soil medium, whereas phosphate-P and metals were significantly retained indicating sorption-mediated transport. These findings support the importance of hydraulics, in combination with the soil medium, when creating bioretention systems for bioremediation that are effective for various rainfall sizes and intervals.

  20. 一种船用液压舵机控制系统设计%Design of Hydraulic Servo Control System for Ship

    Institute of Scientific and Technical Information of China (English)

    汪永生; 王洪波

    2014-01-01

    Aiming at small and medium ships,an open-loop type hydraulic servo control system was designed which had a simple structure and taking up small space. Adopting the system,the rudder machine works more steadily.%针对中小型船舶,设计一种结构简单、占用空间小的开式回路液压控制系统,同时采用了回油节流调速回路,使得舵机工作比较平稳。