WorldWideScience

Sample records for waterjets

  1. Pure waterjet drilling of articular bone

    OpenAIRE

    Biskup, Christian; Dunnen, Steven den; Kraaij, Gert; Kerkhoffs, Gino M. M. J.; Tuijthof, Gabrielle J. M.

    2015-01-01

    The clinical application of waterjet technology for machining tough human tissues, such as articular bone, has advantages, as it produces clean sharp cuts without tissue heating. Additionally, water supply is possible via flexible tubing, which enables minimally invasive surgical access. This pilot study investigates whether drilling bony tissue with pure waterjets is feasible. Water pressures between 20 and 120 MPa with an orifice of 0.6 mm were used to create waterjets to drill blind boring...

  2. The Propulsive Force of the Water-jet to the Flying Weft in Water-jet Looms

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In order to study the propulsive force on the water-jet to the flying weft in water-jet looms, a dynamic model has been established. Based on the analysis and example testing, an experiential formula of the propulsive force of the water-jet to the flying weft is obtained for the first time. The formula will profit the further research of the water-jet weft insertion and the production of textile.

  3. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    Vu Ngoc Pi

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is generate

  4. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    Vu Ngoc Pi

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is

  5. Performance Enhancement of Abrasive Waterjet Cutting

    NARCIS (Netherlands)

    Vu Ngoc Pi

    2008-01-01

    Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is generate

  6. Long hole waterjet drilling for gas drainage

    Energy Technology Data Exchange (ETDEWEB)

    Matt Stockwell; M. Gledhill; S. Hildebrand; S. Adam; Tim Meyer [CMTE (Australia)

    2003-04-01

    In-seam drilling for gas drainage is now an essential part of operations at many Australian underground coalmines. The objective of this project is to develop and trial a new drilling method for the accurate and efficient installation of long inseam boreholes (>1000 metres). This involves the integration of pure water-jet drilling technology (i.e. not water-jet assisted rotary drilling) developed by CMTE with conventional directional drilling technology. The system was similar to conventional directional drilling methods, but instead of relying on a down-hole-motor (DHM) rotating a mechanical drill bit for cutting, high pressure water-jets were used. The testing of the system did not achieve the full objectives set down in the project plan. A borehole greater than 1000 metres was not achieved. The first trial site had coal that was weathered, oxidized and dry. These conditions significantly affected the ability of the drilling tool to stay 'in-seam'. Due to the poor conditions at the first trial, many experimental objectives were forwarded to the second field trial. In the second trial drilling difficulties were experienced, this was due to the interaction between the confinement of the borehole and the dimensions of the down hole drilling assembly. This ultimately reduced the productivity of the system and the distance that could be drilled within the specified trial periods. Testing in the first field trial did not show any indication that the system would have this difficulty.

  7. Development and evaluation of ultra high pressure waterjet cutting

    NARCIS (Netherlands)

    Susuzlu, T.

    2008-01-01

    Abrasive waterjet (AWJ) cutting is a machining process to cut wide range of materials from soft materials such as rubber, leather to hard materials such as metals by means of a high-velocity slurry jet, formed as a result of injecting abrasive particles into a waterjet. The machining action is the

  8. The application of waterjets for cleaning

    Science.gov (United States)

    Summers, D. A.; Fossey, Robert

    1994-06-01

    The last 25 years has seen a dramatic growth in the use of high pressure waterjets for cleaning purposes. Throughout recorded history and no doubt for a long time before that, the dual role of water as both a solvent and a lubricant has been one of the major ways of washing surfaces down regardless of what the surface was. Also, the power built into a waterjet stream has allowed it to be used in moving material. In ancient Egypt rivers were commonly diverted to erode valuable mineral deposits and it was not until 1852 that the modern innovation of hydraulic mining got its start in the hills around Sacramento. The power of the waterjets used in those mining operations were such that most of the gold in California and later in Idaho and many of the other western states was mined hydraulically. Subsequently, the technology has advanced considerably by the use of increasingly high pressures and smaller jets to the point where today abrasive laden waterjets at pressures above 35,000 psi are becoming the tool of choice for cutting glass, titanium, and composite materials. Applications of high pressure waterjets to cutting are usually however, governed by a different set of requirements to those of the cleaning operation. Specifically, while in a cutting or mining operation one is seeking to remove the most volume of material with the least amount of energy looking for deep cuts and applying a highly focused jet energy to the surface. Frequent cleaning requires the ability to remove only one or two surface coatings which may be very shallow. It is generally important that the underlying material or substrate is not damaged by the cleaning process, and thus, the energy of the jet must often be more diffuse. In contrast also with conventional cutting where the depth of the cut has great importance in cleaning it is the area which can be covered in a given time which better optimizes the process. An example of the types of requirement needed can be illustrated by the failure

  9. Experimental research on water-jet guided laser processing

    Science.gov (United States)

    Li, Ling; Wang, Yang; Yang, Lijun; Chu, Jiecheng

    2007-01-01

    The water-jet guided laser processing is a new compound micro-machining process in which the laser beam passes through the water-jet by full reflection onto the workpiece. In this paper, a new key component:the coupling unit was designed and which would form a long, slim, high-pressure and stable water-jet. The couple unit made the fluid field in the chamber symmetry; the coupling quality of the laser beam and the water-jet could be easily detected by CCD camera. For its excellent surface quality, the nozzle with a \\fgr 0.18mm hole got better machining effect than other nozzles. Aiming at finding optimum machining parameters, experiments were carried out. The results showed the attenuation of laser energy bore relation to water-jet stability. The energy intensity distributed over the water-jet cross section nearly homogeneous and the laser energy nearly did not decrease in long working distance. When water-jet pressure was high, efficient cooling of the workpiece prevented burrs, cracks and heat affected zone from forming. During cutting Si wafer process, nearly no cracking was found; Adjusting reasonable laser parameters grooving 65Mn, the machining accuracy would combine with the speed.

  10. Liver resection in children, using a water-jet.

    Science.gov (United States)

    Hata, Y; Sasaki, F; Takahashi, H; Ohkawa, Y; Taguchi, K; Une, Y; Uchino, J

    1994-05-01

    The water-jet method has been used during hepatic resection in children. The instrument cuts the hepatic tissue by means of a high-pressure fine water-jet, while the exposed intrahepatic vessels are spared injury. Physiological saline was used for the jet water, and pressure of 12 to 15 kilograms of force per square centimeter (kgf/cm2) through a 0.15-mm-diameter nozzle was found to be optimal for cutting the liver parenchyma. The authors evaluated the usefulness of the water-jet dissector (n = 8) during bisegmentectomy or trisegmentectomy in comparison to the Cavitron Ultrasonic Surgical Aspirator (CUSA) (n = 5). The mean operation time was 4.08 +/- 0.87 hours for the water-jet group and 5.08 +/- 1.33 hours for the CUSA group. The mean blood loss was 602 +/- 659 mL for the water-jet group and 1,036 +/- 521 mL for the CUSA group. Although there were no significant differences with respect to operation time, blood loss, or postoperative complications, the liver parenchyma was dissected more easily using the water-jet. The authors believe that the mechanical simplicity and safety of the water-jet method will lead to its more widespread use in liver resection in children.

  11. The effects of nozzle geometry on waterjet breakup at high Reynolds numbers

    Energy Technology Data Exchange (ETDEWEB)

    Vahedi Tafreshi, H.; Pourdeyhimi, B. [Nonwovens Cooperative Research Center, North Carolina State University, NC 27695-8301, Raleigh (United States)

    2003-10-01

    Waterjet breakup is traditionally considered to follow the Ohnesorge classification. In this classification, high Reynolds number waterjets are considered to atomize quickly after discharge. By generating a constricted waterjet where the water flow stays detached all the way through the nozzle, we have observed the first wind-induced breakup mode at high Reynolds numbers. Such a peculiar behavior, however, was not observed in non-constricted waterjets. Our results indicate that, constricted jets do not follow the Ohnesorge classification, in contrast to the non-constricted waterjets. We discuss the impact of nozzle geometry on the characteristics of waterjets and support our discussion by numerical simulations. (orig.)

  12. Landmine Detection and Discrimination Using High-Pressure Waterjets

    Directory of Open Access Journals (Sweden)

    Beetner Daryl G

    2004-01-01

    Full Text Available Methods of locating and identifying buried landmines using high-pressure waterjets were investigated. Methods were based on the sound produced when the waterjet strikes a buried object. Three classification techniques were studied, based on temporal, spectral, and a combination of temporal and spectral approaches using weighted density distribution functions, a maximum likelihood approach, and hidden Markov models, respectively. Methods were tested with laboratory data from low-metal content simulants and with field data from inert real landmines. Results show that the sound made when the waterjet hit a buried object could be classified with a 90% detection rate and an 18% false alarm rate. In a blind field test using 3 types of harmless objects and 7 types of landmines, buried objects could be accurately classified as harmful or harmless 60%–90% of the time. High-pressure waterjets may serve as a useful companion to conventional detection and classification methods.

  13. Influence of Water-jet Nozzle Geometry on Cutting Ability of Soft Material

    Directory of Open Access Journals (Sweden)

    Irwansyah Irwansyah

    2012-06-01

    Full Text Available Hygiene is main reason for food processor to use waterjet cutting system. Traditionally food cutting process is low-quality, unsafe products, procedures and direct contact between product and labor. This paper introduced a low cost waterjet system for cutting soft material as identic food material. The low cost waterjet system has been developed by using a commercial pressure pump for cleaning purposes and modified nozzle. In order to enhance waterjet pressure for cutting products, a modified waterjet nozzle was designed. Paramater design of waterjet system was setup on nozzle orifice diameter 0.5 mm, standoff distance 15 mm, length of nozzle cylindrical tube 2.5 mm. Polycarbonate, polysterene, and polyethelene materials are used as sample product with thickness 2 mm, to represent similar properties with agriculture products. The experimental results indicate good possibilities of waterjet system to cut material in appropriate profile surface. The waterjet also can be used to improve cutting finished surface of food products. Therefore, utilizing a low cost commercial pump and modified nozzle for waterjet system reduces equipment price, operational cost and environmental hazards. It indicates viable technology applied to substitute traditional cutting technology in post harvest agriculture products. Keywords: cutting ability, modified nozzle, polymer material, water-jet system

  14. Study of Water Jet Impulse in Water-Jet Looms

    Institute of Scientific and Technical Information of China (English)

    LI Ke-rang; MA Wei-wei; CHEN Ming

    2005-01-01

    The water jet impulse is brought forward to study the traction force of the water jet to the flying weft in water-jet looms. The distribution of the water jet impulse in the shed is tested by a sensor, and the influence of water jet parameters on the water jet impulse is analyzed.

  15. Breakthrough Energy Savings with Waterjet Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee W. Saperstein; R. Larry Grayson; David A. Summers; Jorge Garcia-Joo; Greg Sutton; Mike Woodward; T.P. McNulty

    2007-05-15

    Experiments performed at the University of Missouri-Rolla's Waterjet Laboratory have demonstrated clearly the ability of waterjets to disaggregate, in a single step, four different mineral ores, including ores containing iron, lead and copper products. The study focused mainly on galena-bearing dolomite, a lead ore, and compared the new technology with that of traditional mining and milling to liberate the valuable constituent for the more voluminous host rock. The technical term for the disintegration of the ore to achieve this liberation is comminution. The potential for energy savings if this process can be improved, is immense. Further, if this separation can be made at the mining face, then the potential energy savings include avoidance of transportation (haulage and hoisting) costs to move, process and store this waste at the surface. The waste can, instead, be disposed into the available cavities within the mine. The savings also include the elimination of the comminution, crushing and grinding, stages in the processing plant. Future prototype developments are intended to determine if high-pressure waterjet mining and processing can be optimized to become cheaper than traditional fragmentation by drilling and blasting and to optimize the separation process. The basic new mining process was illustrated in tests on two local rock types, a low-strength sandstone with hematite inclusions, and a medium to high-strength dolomite commonly used for construction materials. Illustrative testing of liberation of minerals, utilized a lead-bearing dolomite, and included a parametric study of the optimal conditions needed to create a size distribution considered best for separation. The target goal was to have 50 percent of the mined material finer than 100 mesh (149 microns). Of the 21 tests that were run, five clearly achieved the target. The samples were obtained as run-of-mine lumps of ore, which exhibited a great deal of heterogeneity within the samples. This

  16. Technical Possibilities of Noise Reduction in Material Cutting by Abrasive Water-jet

    OpenAIRE

    Radvanská, Agáta; Ergić, Todor; IVANDIĆ, Željko; Hloch, Sergej; Valiček, Jan; Mullerova, Jana

    2009-01-01

    The technical procedure of noise reduction in material cutting by abrasive water-jet is described in this paper. The paper is aimed at the implementation of technical possibilities of noise reduction in the cutting of material by abrasive water-jet technology. Both the theoretical and experimental investigations were performed to verify and specify the new findings in the reduction of acoustic sound pressure at abrasive water-jet machining of engineering materials. By means of identification,...

  17. Pure waterjet drilling of articular bone: an in vitro feasibility study:

    OpenAIRE

    Biskup, Christian; Dunnen, Steven den; Kerkhoffs, Gino M. M. J.; Kraaij, Gert; Tuijthof, Gabrielle J. M.

    2013-01-01

    The clinical application of waterjet technology for machining tough human tissues, such as articular bone, has advantages, as it produces clean sharp cuts without tissue heating. Additionally, water supply is possible via flexible tubing, which enables minimally invasive surgical access. This pilot study investigates whether drilling bony tissue with pure waterjets is feasible. Water pressures between 20 and 120 MPa with an orifice of 0.6 mm were used to create waterjets to drill blind boring...

  18. Experimental evaluation of water-jet dissection in endoscopic surgery.

    Science.gov (United States)

    Cuschieri, A

    1994-01-01

    The problems associated with high-velocity high-pressure water-jet dissection were investigated by in-vivo experiments using endoscopic equipment. Three problems were identified: backspray with fouling of the optic, poor control of the depth of cut, and detachment of tissue fragments and isolated cells which contaminate the operative field. The first two problems have been resolved by adoption of a hooded hand-piece and the incorporation of an adjustable back stop. A "dry" system which enables the evacuation of the back spray may deal with the problem of contamination of the operative field by detached cells but further in-vivo experiments are needed to confirm this. Until then, water-jet cutting is considered unsafe for both open and endoscopic surgery in patients undergoing extirpative procedures for cancer because of the risk of tumour seeding within the peritoneal cavity.

  19. Comparisons of Hydraulic Performance in Permanent Maglev Pump for Water-Jet Propulsion

    Directory of Open Access Journals (Sweden)

    Puyu Cao

    2014-08-01

    Full Text Available The operation of water-jet propulsion can generate nonuniform inflow that may be detrimental to the performance of the water-jets. To reduce disadvantages of the nonuniform inflow, a rim-driven water-jet propulsion was designed depending on the technology of passive magnetic levitation. Insufficient understanding of large performance deviations between the normal water-jets (shaft and permanent maglev water-jets (shaftless is a major problem in this paper. CFD was directly adopted in the feasibility and superiority of permanent maglev water-jets. Comparison and discussion of the hydraulic performance were carried out. The shaftless duct firstly has a drop in hydraulic losses (K1, since it effectively avoids the formation and evolution of the instability secondary vortex by the normalized helicity analysis. Then, the shaftless intake duct improves the inflow field of the water-jet pump, with consequencing the drop in the backflow and blocking on the blade shroud. So that the shaftless water-jet pump delivers higher flow rate and head to the propulsion than the shaft. Eventually, not only can the shaftless model increase the thrust and efficiency, but it has the ability to extend the working range and broaden the high efficiency region as well.

  20. Neutralization of potential land mine hazards by abrasive waterjet use

    Science.gov (United States)

    Summers, David A.; Fossey, Robert D.; Thompson, S. J.

    1998-09-01

    A method of neutralizing landmines in which the integrity of the surrounding terrain is retained is herein described. High pressure waterjets which can be used to detect the presence of landmines can then be used to remove the soil and other cover in a plane immediately adjacent to and around the mine so that the side of the mine can be visually inspected through a remote television camera. At that time the flow of water is channeled through a line in which small particles of sand are added to the waterjet which is at a pressure of between 3,000 and 10,000 psi depending on the device which is used. Jet flow rates are on the order of 5 gpm depending on the nozzle configuration used. By bringing this abrasive stream in along a lateral plane through the mine it is possible to intersect, and neutralize, the fusing systems most likely to be used to initiate the charge, in a single pass. At higher flow rates, as the cut is made the jet will generate significant turbulence in the mine body, sufficient to remove a considerable quantity of the explosive which is resident within the mine at the same time as the mine is being dissected. The precision of cut achievable is shown by the longitudinal cutting into two parts of live detonators, as well as representative mine bodies.

  1. Characterization of Effective Parameters in Abrasive Waterjet Rock Cutting

    Science.gov (United States)

    Oh, Tae-Min; Cho, Gye-Chun

    2014-03-01

    The rock cutting performance of an abrasive waterjet is affected by various parameters. In this study, rock cutting tests are conducted with different energy (i.e., water pressure, traverse speed, and abrasive feed rate), geometry (i.e., standoff distance), and material parameters [i.e., uniaxial compressive strength (UCS)]. In particular, experimental tests are carried out at a long standoff distance (up to 60 cm) to consider field application. The effective parameters of the rock cutting process are identified based on the relationships between the cutting performance indices (depth, width, and volume) and parameters. In addition, the cutting efficiency is analyzed with effective parameters as well as different pump types and the number of cutting passes considering the concept of kinetic jet energy. Efficiency analysis reveals that the cutting depth efficiency tends to increase with an increase in the water pressure and traverse speed and with a decrease in the standoff distance and UCS. Cutting volume efficiency strongly depends on standoff distance. High efficiency of cutting volume is obtained at a long standoff distance regardless of the pump type. The efficiency analysis provides a realistic way to optimize parameters for abrasive waterjet rock excavation.

  2. Surface Smoothing of Blasted Glass Micro-Channels Using Abrasive Waterjet

    Energy Technology Data Exchange (ETDEWEB)

    Son, Sunggyun; Han, Solyi; Kim, Wookbae [Korea Polytechnic Univ., Siheung (Korea, Republic of); Sung, Inha [Hannam Univ., Daejeon (Korea, Republic of)

    2013-12-15

    Powder blasting, which is an efficient micromachining method for glass, silicon, and ceramics, has a critical disadvantage in that the surface finish is poor owing to the brittle fracture of materials. Low-pressure waterjet machining can be applied to smoothen the rough surface inside the blasted structure. In this study, the surface roughness and sectional dimension of micro-channels are observed during the repetitive application of a waterjet to blasted micro-channels. The asperities and subsurface cracks created by blasting are removed by waterjet machining. Along with the surface roughness, it is found that the sectional dimension increases and the edges of the finished micro-channel become slightly round. Finally, a microfluidic chip is machined by the blasting-waterjet process and a transparent microfluidic channel is obtained efficiently.

  3. Experiment and simulation study of laser dicing silicon with water-jet

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Jiading; Long, Yuhong, E-mail: longyuhong@guet.edu.cn; Tong, Youqun; Yang, Xiaoqing; Zhang, Bin; Zhou, Zupeng

    2016-11-30

    Highlights: • The explosive melt expulsion could be a dominant process for the laser ablating silicon in liquids with ns-pulsed laser of 1064 nm irradiating. • Self-focusing phenomenon was found and its causes are analyzed. • SPH modeling technique was employed to understand the effect of water and water-jet on debris removal during water-jet laser machining. - Abstract: Water-jet laser processing is an internationally advanced technique, which combines the advantages of laser processing with water jet cutting. In the study, the experiment of water-jet laser dicing are conducted with ns pulsed laser of 1064 nm irradiating, and Smooth Particle Hydrodynamic (SPH) technique by AUTODYN software was modeled to research the fluid dynamics of water and melt when water jet impacting molten material. The silicon surface morphology of the irradiated spots has an appearance as one can see in porous formation. The surface morphology exhibits a large number of cavities which indicates as bubble nucleation sites. The observed surface morphology shows that the explosive melt expulsion could be a dominant process for the laser ablating silicon in liquids with nanosecond pulse laser of 1064 nm irradiating. Self-focusing phenomenon was found and its causes are analyzed. Smooth Particle Hydrodynamic (SPH) modeling technique was employed to understand the effect of water and water-jet on debris removal during water-jet laser machining.

  4. Dimensionless Numerical Approaches for the Performance Prediction of Marine Waterjet Propulsion Units

    Directory of Open Access Journals (Sweden)

    Marco Altosole

    2012-01-01

    Full Text Available One of the key issues at early design stage of a high-speed craft is the selection and the performance prediction of the propulsion system because at this stage only few information about the vessel are available. The objective of this work is precisely to provide the designer, in the case of waterjet propelled craft, with a simple and reliable calculation tool, able to predict the waterjet working points in design and off-design conditions, allowing to investigate several propulsive options during the ship design process. In the paper two original dimensionless numerical procedures, one referred to jet units for naval applications and the other more suitable for planing boats, are presented. The first procedure is based on a generalized performance map for mixed flow pumps, derived from the analysis of several waterjet pumps by applying similitude principles of the hydraulic machines. The second approach, validated by some comparisons with current waterjet installations, is based on a complete physical approach, from which a set of non-dimensional waterjet characteristics has been drawn by the authors. The presented application examples show the validity and the degree of accuracy of the proposed methodologies for the performance evaluation of waterjet propulsion systems.

  5. Resection of C6 gliomas in rats with the aid of the waterjet technique.

    Science.gov (United States)

    Keiner, Doerthe; Heimann, Axel; Kronfeld, Andrea; Sommer, Clemens; Mueller-Forell, Wibke; Kempski, Oliver; Oertel, Joachim

    2016-07-01

    While clinically the safety and efficacy of waterjet resection of brain tumors have been shown, evidence that waterjet dissection improves tumor resection radicality in comparison with conventional techniques is still missing. In the present study, resection radicality and tumor-free long-term survival of both techniques were evaluated in a C6-glioma model. Fifty-thousand C6-glioma cells were stereotactically transplanted in the left frontal lobe of 100 male Sprague-Dawley rats. After MRI-scanning for evaluation of tumor extension, microsurgical tumor resection was performed with conventional techniques (n=50) or with the waterjet dissector at pressures of 6bar (n=50). Twenty-five animals of each group were sacrificed after surgery for histological analysis. For analysis of survival after tumor resection, twenty-five animals of each group were followed-up to analyze tumor-free survival using the Kaplan Meier method. In the waterjet group, the resection cavity was free of C6-tumor cells in 10/25 (40%) rats showing a trend (p=0.3) towards better resection radicality compared to the rats that were treated conventionally (7/10; 28%). R1-resection with up to 250C6 cells/object slice was found in 14/25 (56%) rats after waterjet dissection compared to 6/25 (24%) rats treated conventionally showing significance (prats. In this experimental model, waterjet tumor resection did reveal significantly better resection radicality compared to the conventional technique. Although a direct transfer of these results to human glioma surgery is prohibited, the waterjet technique might contribute to the best possible resection radicality in human gliomas. Nevertheless, tumor cell spreading remains a major problem. Further studies have to address that the surgical results - in deed - improve the postoperative outcome. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Abrasive waterjet machining of fiber reinforced composites: A review

    Science.gov (United States)

    Kalla, D. K.; Dhanasekaran, P. S.; Zhang, B.; Asmatulu, R.

    2012-04-01

    Machining of fiber reinforced polymer (FRP) composites is a major secondary manufacturing activity in the aircraft and automotive industries. Traditional machining of these composites is difficult due to the high abrasiveness nature of their reinforcing constituents. Almost all the traditional machining processes involve in the dissipation of heat into the workpiece which can be resulted in damage to workpiece and rapid wear of the cutting tool. This serious issue has been overcome by water jetting technologies. Abrasive waterjet machining (AWJM) is a nontraditional method and one of the best options for machining FRPs. This paper presents a review of the ongoing research and development in AWJM of FRPs, with a critical review of the physics of the machining process, surface characterization, modeling and the newer application to the basic research. Variable cutting parameters, limitations and safety aspects of AWJM and the noise related issues due to high flow rate of water jet will be addressed. Further challenges and scope of the future development in AWJM are also presented in detail.

  7. Correlation Between Particle Velocities and Conditions of Abrasive Waterjet Formation

    Science.gov (United States)

    Chen, Wei-Long

    1990-01-01

    The velocities of water and abrasive particles in abrasive waterjet(AWJ) were measured by the use of Laser Transit Anemometer(LTA). A setup for the velocity measurement was constructed and a statistical technique was used to improve the accuracy of the velocity determination. A comparison of the magnitude of velocities determined by LTA, Piezoelectric Force Transducer and Schlieren Photograph clearly indicates the feasibility of the use of LTA. The velocities of water and particles were measured for different diameters of water and slurry nozzles, abrasive mass flow rates and particle sizes. The performed experiments enabled us to evaluate the effects of conditions of jet formation on the particles velocities. An empirical equation for the prediction of particles velocities was constructed by the use of obtained results. The coefficient of correlation between experimental and computed results is equal to 0.93. The acquired information can be used to select the operational parameters in AWJ cutting. The obtained results also provide information on the acceleration mechanism of entrained particles, which may be used to improve the design of slurry nozzle.

  8. Experiment and simulation study of laser dicing silicon with water-jet

    Science.gov (United States)

    Bao, Jiading; Long, Yuhong; Tong, Youqun; Yang, Xiaoqing; Zhang, Bin; Zhou, Zupeng

    2016-11-01

    Water-jet laser processing is an internationally advanced technique, which combines the advantages of laser processing with water jet cutting. In the study, the experiment of water-jet laser dicing are conducted with ns pulsed laser of 1064 nm irradiating, and Smooth Particle Hydrodynamic (SPH) technique by AUTODYN software was modeled to research the fluid dynamics of water and melt when water jet impacting molten material. The silicon surface morphology of the irradiated spots has an appearance as one can see in porous formation. The surface morphology exhibits a large number of cavities which indicates as bubble nucleation sites. The observed surface morphology shows that the explosive melt expulsion could be a dominant process for the laser ablating silicon in liquids with nanosecond pulse laser of 1064 nm irradiating. Self-focusing phenomenon was found and its causes are analyzed. Smooth Particle Hydrodynamic (SPH) modeling technique was employed to understand the effect of water and water-jet on debris removal during water-jet laser machining.

  9. Assessment of possibility of metal waterjet cutting wastes use in building materials production

    Directory of Open Access Journals (Sweden)

    Skanavi Nataliya

    2017-01-01

    Full Text Available The paper is aimed at studying the composition and properties of the wastes generated during metal waterjet cutting and assessing the possibility of their use in building materials production. The essence of waterjet cutting process, waste generation mechanism, waste accumulation volumes at enterprises are described. The composition and properties of the used abradant – garnet sand is given and the features of its destruction during cutting are revealed. Waterjet cutting wastes are comprehensively studies: average and bulk density, granulometric composition, chemical composition are determined, various fractions are studied with an electronic microscope. It is revealed that during cutting abradant particles are destroyed, a large amount of dust fraction emerges with the particles of cut metal mixed into it. The metal waterjet cutting wastes are found to be very small, practically monofractive, heavy sands with a high content of dust fraction, which chemical composition is dominated by oxides of iron, silicon and aluminum. This characteristic of the wastes has allowed us to outline possible ways of how to use them: in ceramic items production as thinning agents and fluxing agents, in Portland cement production as a correcting iron-containing agent, as a mortar filler, including special mortars, as a building materials volumetric staining pigment, etc.

  10. Outburst control in soft and outburst prone coal seam using the waterjet slotting technique from modeling to field work

    Institute of Scientific and Technical Information of China (English)

    LU Ting-kan; YAO Zai-feng; CHANG Fang-tao; ZHAO Zhi-jian

    2012-01-01

    The paper discussed a comprehensive numerical simulation and field work by the usage of waterjet slotting technique to prevent the occurrence of outbursts in soft and outburst prone coal seams.This was based on the geological and geomechanical conditions of Jinjiachong Colliery,Guizhou Province,associated with varied waterjet slotting parameters such as slotting penetration,slotting thickness and slotting distance along the length of borehole.Also,to understand the variation of internal stress of coal seams after waterjet slotting application,the internal stress levels were compared with and without slotting application,and the results indicate that the internal effective stress levels can be reduced to 70% and 45% for the vertical and horizontal stresses,respectively,and the gas concentration can be increased up to 5 times when the waterjet slotting is applied.

  11. A Review on Current Research and Development in Abrasive Waterjet Machining

    Directory of Open Access Journals (Sweden)

    M. M. Korat

    2014-01-01

    Full Text Available Abrasive waterjet machining (AWJM is an emerging machining technology option for hard material parts that are extremely difficult-to-machine by conventional machining processes. A narrow stream of high velocity water mixed with abrasive particles gives relatively inexpensive and environment friendly production with reasonably high material removal rate. Because of that abrasive waterjet machining has become one of the leading manufacturing technologies in a relatively short period of time. This paper reviews the research work carried out from the inception to the development of AWJM within the past decade. It reports on the AWJM research relating to improving performance measures, monitoring and control of process, optimizing the process variables. A wide range of AWJM industrial applications for different category of material are reported with variations. The paper also discusses the future trend of research work in the same area.

  12. Water-jet guided laser: possibilities and potential for singulation of electronic packages

    Science.gov (United States)

    Wagner, Frank R.; Spiegel, Akos; Vago, Nandor; Richerzhagen, Bernold

    2002-06-01

    Singulation of packages is an important step in the manufacturing of IC devices. Presently, the most widely used technique is abrasive sawing. Due to the combination of different materials used in packages such as copper and mold compound, the saw rapidly blunts and also conventional laser cutting by a water-jet with the high precision and speed of a laser cut and is now applied into electronic package singulation.

  13. Fuzzy prediction and experimental verification of road surface cleaning rate by pure waterjets

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The cleaning parameters affecting cleaning rate using pure waterjets to clean road surface was researched. A mathematical model for predicting cleaning rate was established using fuzzy mathematical method. A fuzzy rule base characterizing the relationship between input and output parameters was built through experiments. The prediction of cleaning rate was achieved under the condition of given input parameters by rule-based fuzzy reasoning. The prediction results were analyzed through experimental verification.

  14. Influence of Spatially Varying Flow on the Dynamic Response of a Waterjet inside an SES

    Directory of Open Access Journals (Sweden)

    Michael R. Motley

    2014-01-01

    Full Text Available Surface Effect Ships (SES are a promising fuel-efficient ship technology that typically carry most of their weight on an air cushion. To accommodate its shallow draft and slender side hulls and to absorb the high thrust and power required for high-speed applications, waterjets are typically used as the primary propulsion system. A waterjet typically has a flush mounted inlet and operates under complex three-dimensional flow conditions that result in highly nonuniform flows. The objectives of this work are to quantify the flow nonuniformity and the influence of unsteady cavitation on the response of an SES-waterjet system and to investigate the effect of flow nonuniformity and cavitation on the dynamic hydroelastic response of the rotor and stator blades. The results showed that as the flow advances through the pump, the ingested boundary layer from the bottom of the side hulls becomes increasingly nonuniform, particularly between the rotor and stator. The flow nonuniformity was shown to result in hydrodynamic load fluctuations and high side forces on the rotor and stator blades. The unbalanced blade loads lead to the generation of net upward forces on the pump casing and shaft. Flow nonuniformity also leads to unsteady cavitation and unsteady blade stresses and deformations.

  15. An investigation on co-axial water-jet assisted fiber laser cutting of metal sheets

    Science.gov (United States)

    Madhukar, Yuvraj K.; Mullick, Suvradip; Nath, Ashish K.

    2016-02-01

    Water assisted laser cutting has received significant attention in recent times with assurance of many advantages than conventional gas assisted laser cutting. A comparative study between co-axial water-jet and gas-jet assisted laser cutting of thin sheets of mild steel (MS) and titanium (Ti) by fiber laser is presented. Fiber laser (1.07 μm wavelength) was utilised because of its low absorption in water. The cut quality was evaluated in terms of average kerf, projected dross height, heat affected zone (HAZ) and cut surface roughness. It was observed that a broad range process parameter could produce consistent cut quality in MS. However, oxygen assisted cutting could produce better quality only with optimised parameters at high laser power and high cutting speed. In Ti cutting the water-jet assisted laser cutting performed better over the entire range of process parameters compared with gas assisted cutting. The specific energy, defined as the amount of laser energy required to remove unit volume of material was found more in case of water-jet assisted laser cutting process. It is mainly due to various losses associated with water assisted laser processing such as absorption of laser energy in water and scattering at the interaction zone.

  16. Performance optimization of water-jet assisted underwater laser cutting of AISI 304 stainless steel sheet

    Science.gov (United States)

    Mullick, Suvradip; Madhukar, Yuvraj K.; Roy, Subhransu; Nath, Ashish K.

    2016-08-01

    Recent development of water-jet assisted underwater laser cutting has shown some advantages over the gas assisted underwater laser cutting, as it produces much less turbulence, gas bubble and aerosols, resulting in a more gentle process. However, this process has relatively low efficiency due to different losses in water. Scattering is reported to be a dominant loss mechanism, which depends on the growth of vapor layer at cut front and its removal by water-jet. Present study reports improvement in process efficiency by reducing the scattering loss using modulated laser power. Judicious control of laser pulse on- and off-time could improve process efficiency through restricting the vapor growth and its effective removal by water-jet within the laser on- and off-time, respectively. Effects of average laser power, duty cycle and modulation frequency on specific energy are studied to get an operating zone for maximum efficiency. Next, the variation in laser cut quality with different process parameters are studied within this operating zone using Design of experiment (DOE). Response surface methodology (RSM) is used by implementing three level Box-Behnken design to optimize the variation in cut quality, and to find out the optimal process parameters for desired quality. Various phenomena and material removal mechanism involved in this process are also discussed.

  17. Comparative Study of Remote Fiber Laser and Water-Jet Guided Laser Cutting of Thin Metal Sheets

    Science.gov (United States)

    Hock, Klaus; Adelmann, Benedikt; Hellmann, Ralf

    This article presents a comparison between remote laser cutting with a fiber laser and water-jet guided laser cutting using a 532 nm solid state laser. Complex contours are processed in stainless steel and brass sheets (thickness ≤ 100 μm), respectively. Results for achievable quality and productivity as well as possible applications for both systems are shown and discussed. We sustained dross free cuts with almost no heat affected zone and small kerf width for the water-jet guided process, whereas small dross, notable heat affected zone and varying kerf width where observed for remote cutting. However, process times for the water-jet guided process where considerably higher than those for remote cutting.

  18. Tomographic particle image velocimetry of a water-jet for low volume harvesting of fat tissue for regenerative medicine

    Directory of Open Access Journals (Sweden)

    Drobek Christoph

    2015-09-01

    Full Text Available Particle Image Velocimetry (PIV measurements of a water-jet for water-assisted liposuction (WAL are carried out to investigate the distribution of velocity and therefore momentum and acting force on the human sub-cutaneous fat tissue. These results shall validate CFD simulations and force sensor measurements of the water-jet and support the development of a new WAL device that is able to harvest low volumes of fat tissue for regenerative medicine even gentler than regular WAL devices.

  19. Performance analysis of cutting graphite-epoxy composite using a 90,000psi abrasive waterjet

    Science.gov (United States)

    Choppali, Aiswarya

    Graphite-epoxy composites are being widely used in many aerospace and structural applications because of their properties: which include lighter weight, higher strength to weight ratio and a greater flexibility in design. However, the inherent anisotropy of these composites makes it difficult to machine them using conventional methods. To overcome the major issues that develop with conventional machining such as fiber pull out, delamination, heat generation and high tooling costs, an effort is herein made to study abrasive waterjet machining of composites. An abrasive waterjet is used to cut 1" thick graphite epoxy composites based on baseline data obtained from the cutting of ¼" thick material. The objective of this project is to study the surface roughness of the cut surface with a focus on demonstrating the benefits of using higher pressures for cutting composites. The effects of major cutting parameters: jet pressure, traverse speed, abrasive feed rate and cutting head size are studied at different levels. Statistical analysis of the experimental data provides an understanding of the effect of the process parameters on surface roughness. Additionally, the effect of these parameters on the taper angle of the cut is studied. The data is analyzed to obtain a set of process parameters that optimize the cutting of 1" thick graphite-epoxy composite. The statistical analysis is used to validate the experimental data. Costs involved in the cutting process are investigated in term of abrasive consumed to better understand and illustrate the practical benefits of using higher pressures. It is demonstrated that, as pressure increased, ultra-high pressure waterjets produced a better surface quality at a faster traverse rate with lower costs.

  20. WATER-JET CUTTING MACHINE NOW AVAILABLE FROM THE CERN RAW MATERIALS STORES

    CERN Document Server

    2007-01-01

    The CERN Raw Materials Stores has recently acquired a new water-jet cutting machine. The machine is capable of cutting all types and shapes of materials up to 70 mm in thickness, with an accuracy of +/- 0.1mm/m. For the time being, users requiring materials to be cut should supply drawings in DXF, DWG or IGES (AutoCad) file format. The machine will be operational as of 1st October 2007. The Stores Team Paulo Dos Santos FI-LS-MM 72308

  1. WATER-JET CUTTING MACHINE NOW AVAILABLE FROM THE CERN RAW MATERIALS STORES

    CERN Multimedia

    2007-01-01

    The CERN Raw Materials Stores has recently acquired a new water-jet cutting machine. The machine is capable of cutting all types and shapes of materials up to 70 mm in thickness, with an accuracy of +/- 0.1mm/m. For the time being, users requiring materials to be cut should supply drawings in DXF, DWG or IGES (AutoCad) file format. The machine will be operational as of 1st October 2007. The Stores Team Paulo Dos Santos FI-LS-MM 72308

  2. Surgical and pathomorphological results of total mesorectumectomy by using waterjet dissection technique in patients with rectal cancer

    Directory of Open Access Journals (Sweden)

    D. V. Sidorov

    2016-01-01

    Full Text Available Background. The paper presents our own experience of using a waterjet dissector ERBEJET2® in the course of surgical interventions for colorectal cancer. This experience is unique for Russia.Materials and methods. Waterjet dissection method associated with total  mesorectumectomy was used by us in 20 patients suffering from rectal cancer. An average age of patients was 59.2 ± 13.9 years. In all the patients surgeries were performed for adenogenic colorectal cancer, morphologically verified at the preoperative stage. Resected preparations were studied on morphological level. For comparison, two control groups of 20 patients were selected, in which the rectum mobilization was performed by using monopolar coagulator and harmonic scalpel. The studied groups were matched by gender, age, location and the tumor extent. All the surgeries were performed by one surgical team.Results. Results of the study demonstrated advantages of waterjet dissection when performing total mesorectumectomy due to a minimum depth of tissue damage on the lateral margin of resection.Conclusion. Waterjet dissectors have taken their place in the extensive list of tools used when performing surgical interventions for colorectal cancer, that allows to expect an improvement of functional and oncological results of the surgical treatment.

  3. An investigation on surface roughness of granite machined by abrasive waterjet

    Indian Academy of Sciences (India)

    Gokhan Aydin; Izzet Karakurt; Kerim Aydiner

    2011-07-01

    Abrasive waterjet (AWJ) cutting is an emerging technology which enables the shaping of practically all engineering materials. However, AWJ cutting may cause roughness and waviness on the cut surface. This significantly affects the dimensional accuracy of the machined part and the quality of surface finish. In this study, the surface roughness of three granites is experimentally investigated for varying process parameters in abrasive waterjet. The philosophy of the Taguchi design is followed in the experimental study. Effects of the control (process) factors on the surface roughness are presented in terms of the mean of means responses. Additionally, the data obtained are evaluated statistically using the analysis of variance (ANOVA) to determine significant process parameters affecting the surface roughness. Furthermore, effects of the material properties on the surface roughness are assessed. It was statistically found that the water pressure and the abrasive flow rate are the most significant factors influencing the surface roughness of granites. Additionally, a consistent relationship between the material grain size and surface roughness of the granites was observed.

  4. Rock Cutting Depth Model Based on Kinetic Energy of Abrasive Waterjet

    Science.gov (United States)

    Oh, Tae-Min; Cho, Gye-Chun

    2016-03-01

    Abrasive waterjets are widely used in the fields of civil and mechanical engineering for cutting a great variety of hard materials including rocks, metals, and other materials. Cutting depth is an important index to estimate operating time and cost, but it is very difficult to predict because there are a number of influential variables (e.g., energy, geometry, material, and nozzle system parameters). In this study, the cutting depth is correlated to the maximum kinetic energy expressed in terms of energy (i.e., water pressure, water flow rate, abrasive feed rate, and traverse speed), geometry (i.e., standoff distance), material (i.e., α and β), and nozzle system parameters (i.e., nozzle size, shape, and jet diffusion level). The maximum kinetic energy cutting depth model is verified with experimental test data that are obtained using one type of hard granite specimen for various parameters. The results show a unique curve for a specific rock type in a power function between cutting depth and maximum kinetic energy. The cutting depth model developed here can be very useful for estimating the process time when cutting rock using an abrasive waterjet.

  5. Endoscopic band ligation with a water-jet scope for the treatment of colonic diverticular hemorrhage.

    Science.gov (United States)

    Ishii, Naoki; Itoh, Toshiyuki; Uemura, Masayo; Maruyama, Masataka; Horiki, Noriyuki; Setoyama, Takeshi; Matsuda, Michitaka; Suzuki, Shoko; Iizuka, Yusuke; Fukuda, Katsuyuki; Fujita, Yoshiyuki

    2010-07-01

    Although lower gastrointestinal bleeding generally has a less severe course and stops spontaneously in most cases without therapeutic intervention, some patients require endoscopic, surgical, or angiographic treatment depending on the nature of the bleeding. We applied endoscopic band ligation (EBL) with a water-jet scope to bleeding colonic diverticula and evaluated the efficacy and safety of EBL retrospectively. Five consecutive patients were diagnosed as having colonic diverticular hemorrhage, and were treated with EBL at St Luke's International Hospital in Tokyo from June 2009 to August 2009. Comorbid diseases, usage of anti-platelet agents, hemoglobin level on admission, procedural time, complications such as perforation and abscess formation, and rebleeding after EBL were retrospectively evaluated. In all cases, EBL achieved successful immediate hemostasis without any procedural complications. In four of five cases, bleeding colonic diverticula were everted after EBL. The mean length of hospital stay after EBL was 5 days (range 4-8 days). No patient exhibited clinical evidence of further bleeding during the mean follow-up period of 3 months (range 2-4 months), and no further intervention was needed after EBL. EBL with a water-jet scope is considered to be a safe and effective endoscopic treatment for colonic diverticular hemorrhage.

  6. Selection of the most influential factors on the water-jet assisted underwater laser process by adaptive neuro-fuzzy technique

    Science.gov (United States)

    Nikolić, Vlastimir; Petković, Dalibor; Lazov, Lyubomir; Milovančević, Miloš

    2016-07-01

    Water-jet assisted underwater laser cutting has shown some advantages as it produces much less turbulence, gas bubble and aerosols, resulting in a more gentle process. However, this process has relatively low efficiency due to different losses in water. It is important to determine which parameters are the most important for the process. In this investigation was analyzed the water-jet assisted underwater laser cutting parameters forecasting based on the different parameters. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data in order to select the most influential factors for water-jet assisted underwater laser cutting parameters forecasting. Three inputs are considered: laser power, cutting speed and water-jet speed. The ANFIS process for variable selection was also implemented in order to detect the predominant factors affecting the forecasting of the water-jet assisted underwater laser cutting parameters. According to the results the combination of laser power cutting speed forms the most influential combination foe the prediction of water-jet assisted underwater laser cutting parameters. The best prediction was observed for the bottom kerf-width (R2 = 0.9653). The worst prediction was observed for dross area per unit length (R2 = 0.6804). According to the results, a greater improvement in estimation accuracy can be achieved by removing the unnecessary parameter.

  7. Application of the fractal theory for evaluating effects of coal comminution by waterjet

    Institute of Scientific and Technical Information of China (English)

    Yaqing Li; Greg Galecki; Gul Akar; Sezai Sen; Yutao Zhang

    2014-01-01

    Comminution of coal to ultrafine sizes by high-pressure waterjet provides a novel method for preparation of coal-water fuels for next generation, near-zero emission electric power generation. The particle size distribution (PSD) of ground coal is a key parameter in the preparation of slurries as it determines the settling behavior of the particles and viscosity of the coal-water mixture. There are several methods available for representation and evaluation of particle size analysis data. However, fractal theory provides a means by which the entire PSD of comminuted materials can be quantified by using of a specific and exact value. In this paper, a volume-based fractal model was deduced to characterize the PSD of the coal which is ground in a specially designed comminution cell. During the size reduction process, the inlet pressures up to 276 MPa were used.

  8. Effect of multiple passes treatment in waterjet peening on fatigue performance

    Science.gov (United States)

    Azhari, Azmir; Schindler, Christian; Godard, Claudia; Gibmeier, Jens; Kerscher, Eberhard

    2016-12-01

    The influence of waterjet peening on the residual stresses and fatigue performance of AISI 304 is investigated. The specimen surfaces were treated with multiple jet passes. The fatigue strength was evaluated using an alternating bending fatigue tester. The results of XRD measurements showed that a higher amount of compressive residual stresses is induced in the treated specimens. This strengthening layer is limited within the first 100 μm below the surface, which had been confirmed by micro hardness measurements. Even though the treated specimens showed compressive residual stresses the fatigue limit is lower than that of the untreated specimens. The roughness of the surface and the resulting notch effect seems to be stronger than the positive effect of the hardened layer.

  9. Kerf modelling in abrasive waterjet milling using evolutionary computation and ANOVA techniques

    Science.gov (United States)

    Alberdi, A.; Rivero, A.; Carrascal, A.; Lamikiz, A.

    2012-04-01

    Many researchers demonstrated the capability of Abrasive Waterjet (AWJ) technology for precision milling operations. However, the concurrence of several input parameters along with the stochastic nature of this technology leads to a complex process control, which requires a work focused in process modelling. This research work introduces a model to predict the kerf shape in AWJ slot milling in Aluminium 7075-T651 in terms of four important process parameters: the pressure, the abrasive flow rate, the stand-off distance and the traverse feed rate. A hybrid evolutionary approach was employed for kerf shape modelling. This technique allowed characterizing the profile through two parameters: the maximum cutting depth and the full width at half maximum. On the other hand, based on ANOVA and regression techniques, these two parameters were also modelled as a function of process parameters. Combination of both models resulted in an adequate strategy to predict the kerf shape for different machining conditions.

  10. Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

    2012-02-01

    Laboratory tests were conducted to determine the fatigue performance of abrasive-waterjet- (AWJ-) machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results of the titanium specimens not only confirmed our previous findings in aluminum dog-bone specimens but in comparison also further enhanced the fatigue performance of the titanium. In addition, titanium is known to be difficult to cut, particularly for thick parts, however AWJs cut the material 34% faster han stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred ombination for processing aircraft titanium that is fatigue critical.

  11. Experimental research on the machinability of Hardox steel by abrasive waterjet cutting

    Directory of Open Access Journals (Sweden)

    Filip Alexandru Catalin

    2017-01-01

    Full Text Available One of the main present industry challenges is finding the most efficient manufacturing process for a certain part. When parts are made of strong steels like Hardox, their fabrication method is usually difficult. Abrasive waterjet cutting (AWJ is one of the cutting processes which can be used in this case. This paper presents an experimental research on the machinability of Hardox steel by AWJ. The experiments were conducted using a factorial design model considering two of the main influence parameters like the traverse speed and the distance between the nozzle and the surface of the material. Based on the measurement of the dimensions and the roughness of the parts, the influence of the parameters was revealed and analyzed. The manufacturing time was also compared, as it directly influences the production cost. Further research is considered to develop a mathematical model which can be used for a proper choice of the process parameters depending on the initial requirements.

  12. Experimental Investigations into Abrasive Waterjet Machining of Carbon Fiber Reinforced Plastic

    Directory of Open Access Journals (Sweden)

    Prasad D. Unde

    2015-01-01

    Full Text Available Abrasive waterjet machining (AWJM is an emerging machining process in which the material removal takes place due to abrasion. A stream of abrasive particles mixed with filtered water is subjected to the work surface with high velocity. The present study is focused on the experimental research and evaluation of the abrasive waterjet machining process in order to evaluate the technological factors affecting the machining quality of CFRP laminate using response surface methodology. The standoff distance, feed rate, and jet pressure were found to affect kerf taper, delamination, material removal rate, and surface roughness. The material related parameter, orientation of fiber, has been also found to affect the machining performance. The kerf taper was found to be 0.029 for 45° fiber orientation whereas it was 0.036 and 0.038 for 60° and 90°, respectively. The material removal rate is 18.95 mm3/sec for 45° fiber orientation compared to 18.26 mm3/sec for 60° and 17.4 mm3/sec for 90° fiber orientation. The Ra value for 45° fiber orientation is 4.911 µm and for 60° and 90° fiber orientation it is 4.927 µm and 4.974 µm, respectively. Delamination factor is found to be more for 45° fiber orientation, that is, 2.238, but for 60° and 90° it is 2.029 and 2.196, respectively.

  13. Numerical analysis of head degrade law under cavitation condition of contra-rotating axial flow waterjet pump

    Science.gov (United States)

    Huang, D.; Pan, Z. Y.

    2015-01-01

    In order to study the flow-head characteristic curve, the SST turbulence model, homogeneous multiphase model and Rayleigh-Plesset equation were applied to simulate the cavitation characteristics in contra-rotating axial flow waterjet pump under different conditions based on ANSYS CFX software. The distribution of cavity, pressure coefficient of the blade at the design point under different cavitation conditions were obtained. The analysis results of flow field show that the vapour volume distribution on the impeller indicates that the vapour first appears at the leading edge of blade and then extends to the outlet of impeller with the reduction of Net Positive Suction Head Allowance (NPSHA). The present study illustrates that the main reason for the decline of the pump performance is the development of cavitation, and the simulation can truly reflect the cavitation performance of the contra-rotating axial flow waterjet pump.

  14. 医用水刀的应用与实现%Application and Realization of Medical Water-jet

    Institute of Scientific and Technical Information of China (English)

    郑伟; 张西正

    2011-01-01

    The structure, the operating principle of medical water-jet and its application in the medical field are studied. The function which its control system should realize, that is, to achieve the constant pressure water supply as well as the hydraulic pressure limitless velocity modulation is defined. The frequency control constant pressure water supply technology is applied to achieve this function. Some other parts are added to develop the water-jet which is applied as the medical equipment. Medical water-jet has the broad prospect in the surgical operation domain because of its merits such as selective and protective cutting. In the future, water-jet will be used widely in the country gradually.%研究了医用水刀的结构、工作原理及其在医学领域的应用,明确了其控制系统所需实现恒压供水以及水压的无级调速功能,应用变频调速恒压供水技术可实现这一功能,增加了一些其他功能部件,开发出了应用于医学上的水刀设备,指出医用水刀的选择性和保护性切割等优点使其在外科手术领域具有广阔的前景,在不久的将来会在国内逐步得到推广应用.

  15. Water-jet Propulsion with Positive Displacement Pump%正排量泵喷水推进技术

    Institute of Scientific and Technical Information of China (English)

    杨友胜; 朱玉泉; 罗小辉

    2011-01-01

    喷水推进是一种高性能的船舶推进方式.针对当前船舶推进器存在的问题,介绍了一种新型以正排量泵为核心的喷水推进方式,比较分析了正/负排量泵喷水推进两者的优缺点,得出正排量泵喷泵喷是一种能进一步改善船只性能的推进技术.%Water-jet propulsion is a high performance propulsion method. Regarding the current problems in ship propulsion appliances, a new type of water-jet propulsion is introduced, which uses positive displacement (PD) pump as power unit. A comparative study is made between the positive and negative displacement (ND) pump water-jet propulsions. The results show that the PD pump water-jet propulsion can further improves the performance ofwatercraft.

  16. High-speed cutting of thin materials with a Q-switched laser in a water-jet versus conventional laser cutting with a free running laser

    Science.gov (United States)

    Wagner, Frank R.; Boillat, Christophe; Buchilly, Jean-Marie; Spiegel, Akos; Vago, Nandor; Richerzhagen, Bernold

    2003-07-01

    Cutting of thin material, c.f. stencils, stents and thin wafers, is an important market for laser machining. Traditionally this task is performed using flash-lamp pumped, free-running Nd:YAG lasers. Using the water-jet guided laser technology, we experienced that the use of Q-switched lasers leads to superior results while cutting a variety of thin materials. In this technique, the laser is conducted to the work piece by total internal reflection in a thin stable water-jet, comparable to the core of an optical fiber. Utilizing this system, we obtain burr-free, slightly tapered cuts at the same speed as the classical laser cutting and without distinguishable heat affected zone. The main difference is, except the water-jet usage, the pulse duration which is approximately 400 ns instead of 20 to 200 μs in the case of free running lasers. Up to 40'000 high quality apertures per hour can be achieved in stencil mask cutting with the new system. We will compare qualitatively the two possibilities: conventional laser cutting with free-running lasers and water-jet guided laser cutting with Q-switched lasers. The results will be discussed in terms of the different physical effects involved in the material removal upon both methods. In particular the importance of molten material expulsion by the water-jet will be pointed out and compared to the action of the assist-gas. The mentioned effects show that the combination of short pulse laser and water-jet will be beneficial for the production of a wide range of precision parts.

  17. Numerical and Experimental Studies of Cavitation Behavior in Water-Jet Cavitation Peening Processing

    Directory of Open Access Journals (Sweden)

    H. Zhang

    2013-01-01

    Full Text Available Water-jet cavitation peening (WCP is a new technology for the surface modification of metallic materials. The cavitation behavior in this process involves complex and changeable physics phenomena, such as high speed, high pressure, multiple phases, phase transition, turbulence, and unstable features. Thus, the cavitation behavior and impact-pressure distribution in WCP have always been key problems in this field. Numerous factors affect the occurrence of cavitation. These factors include flow-boundary conditions, absolute pressure, flow velocity, flow viscosity, surface tension, and so on. Among these factors, pressure and vapor fraction are the most significant. Numerical simulations are performed to determine the flow-field characteristics of both inside and outside the cavitating nozzle of a submerged water jet. The factors that influence the cavitation intensity of pressure are simulated. Fujifilm pressure-sensitive paper is used to measure the distribution of impact pressure along the jet direction during the WCP process. The results show that submerged cavitation jets can induce cavitation both inside and outside a conical nozzle and a convergent-divergent nozzle when the inlet pressure is 32 MPa. Moreover, the shock wave pressure induced by the collapse of the bubble group reaches up to 300 MPa.

  18. Characterization of nanoparticles from abrasive waterjet machining and electrical discharge machining processes.

    Science.gov (United States)

    Ling, Tsz Yan; Pui, David Y H

    2013-11-19

    Abrasive Waterjet Machining (AWM) and Electrical Discharge Machining (EDM) processes are found to produce nanoparticles during operation. Impacts of engineered nanoparticles released to the environment and biological system have caused much concern. Similarly, the nanoparticles unintentionally produced by the AWM and EDM can lead to comparable effects. By application of the Nanoparticle Tracking Analysis (NTA) technique, the size distribution and concentration of nanoparticles in the water used in AWM and EDM were measured. The particles generally have a peak size of 100-200 nm. The filtration systems of the AWM and EDM processes were found to remove 70% and 90% the nanoparticles present, respectively. However, the particle concentration of the filtered water from the AWM was still four times higher than that found in regular tap water. These nanoparticles are mostly agglomerated, according to the microscopy analysis. Using the electron dispersive spectroscopy (EDS) technique, the particles are confirmed to come from the debris of the materials cut with the equipment. Since AWM and EDM are widely used, the handling and disposal of used filters collected with nanoparticles, release of nanoparticles to the sewer, and potential use of higher performance filters for these processes will deserve further consideration.

  19. Investigation of the Effects of Machining Parameters on Material Removal Rate in Abrasive Waterjet Turning

    Directory of Open Access Journals (Sweden)

    Iman Zohourkari

    2014-05-01

    Full Text Available The effects of the main operational machining parameters on the material removal rate (MRR in abrasive waterjet turning (AWJT are presented in this paper using a statistical approach. The five most common machining parameters such as water pressure, abrasive mass flow rate, cutting head traverse speed, workpiece rotational speed, and depth of cut have been put into a five-level central composite rotatable experimental design (CCRD. The main effects of parameters and the interaction among them were analyzed by means of the analysis of variance (ANOVA and the response surfaces for MRR were obtained fitting a second-order polynomial function. It has been found that depth of cut and cutting head traverse speed are the most influential parameters, whereas the rotational speed is insignificant. In addition, the investigations show that interactions between traverse speed and pressure, abrasive mass flow rate and depth of cut, and pressure and depth of cut are significant on MRR. This result advances the AWJT state of the art. A complete model discussion has been reported drawing interesting considerations on the AWJT process characterising phenomena, where parameters interactions play a fundamental role.

  20. Separation and reconstruction of high pressure water-jet reflective sound signal based on ICA

    Science.gov (United States)

    Yang, Hongtao; Sun, Yuling; Li, Meng; Zhang, Dongsu; Wu, Tianfeng

    2011-12-01

    The impact of high pressure water-jet on the different materials target will produce different reflective mixed sound. In order to reconstruct the reflective sound signals distribution on the linear detecting line accurately and to separate the environment noise effectively, the mixed sound signals acquired by linear mike array were processed by ICA. The basic principle of ICA and algorithm of FASTICA were described in detail. The emulation experiment was designed. The environment noise signal was simulated by using band-limited white noise and the reflective sound signal was simulated by using pulse signal. The reflective sound signal attenuation produced by the different distance transmission was simulated by weighting the sound signal with different contingencies. The mixed sound signals acquired by linear mike array were synthesized by using the above simulated signals and were whitened and separated by ICA. The final results verified that the environment noise separation and the reconstruction of the detecting-line sound distribution can be realized effectively.

  1. Cost minimizing of cutting process for CNC thermal and water-jet machines

    Science.gov (United States)

    Tavaeva, Anastasia; Kurennov, Dmitry

    2015-11-01

    This paper deals with optimization problem of cutting process for CNC thermal and water-jet machines. The accuracy of objective function parameters calculation for optimization problem is investigated. This paper shows that working tool path speed is not constant value. One depends on some parameters that are described in this paper. The relations of working tool path speed depending on the numbers of NC programs frames, length of straight cut, configuration part are presented. Based on received results the correction coefficients for working tool speed are defined. Additionally the optimization problem may be solved by using mathematical model. Model takes into account the additional restrictions of thermal cutting (choice of piercing and output tool point, precedence condition, thermal deformations). At the second part of paper the non-standard cutting techniques are considered. Ones may lead to minimizing of cutting cost and time compared with standard cutting techniques. This paper considers the effectiveness of non-standard cutting techniques application. At the end of the paper the future research works are indicated.

  2. Pengembangan Rancangan Nozzle Waterjet untuk Meningkatkan Kecepatan Renang pada Tank BMP-3F (Infantry Fighting Vehicle

    Directory of Open Access Journals (Sweden)

    Rozzaqi Anata

    2013-09-01

    Full Text Available Negara Kepulauan Republik Indonesia (NKRI memiliki wilayah  perairan yang luas, sehingga pertahanan negara di sektor perairan menjadi lebih dirapatkan. Strategi yang dibentuk adalah dengan memproduksi dan membeli kendaraan tempur. Salah satu kendaraan yang dibeli adalah tank amphibi BMP-3F buatan rusia. Kendaraan tank ini ketika dioperasikan di perairan hanya mencapai kecepatan 10 km/h, oleh karena itu akan dilakukan pengembangan perancangan nozzle waterjet untuk dapat meningkatkan kecepatan renang dari tank BMP-3F. Sehingga dilakukan beberapa modifikasi dari variasi nozzle yang akan dianalisa menggunakan SolidWorks yakni variasi diameter nozzle dari kondisi awal 140 mm hingga menjadi 110 mm, serta perbedaan sudut nozzle yang nantinya akan membentuk cone, dari 10 hingga 40, serta penambahan ulir pada sisi outlet water jet. Dari hasil analisa data dan perhitungan diperoleh untuk hasil thrust tertinggi dengan bentuk nozzle cone variasi 40 menghasilkan thrust sebesar 146,347 kN dengan kecepatan renang meningkat sebesar 89% dari kecepatan awal yakni menjadi 10,017 knot pada saat thrust deduction factor sebesar 0,3076.

  3. Breast reconstruction de novo by water-jet assisted autologous fat grafting – a retrospective study

    Directory of Open Access Journals (Sweden)

    Hoppe, Delia Letizia

    2013-12-01

    Full Text Available [english] Background: Autologous fat grafting has become a frequent, simple, reproducible and low-risk technique for revisional or partial breast reconstruction. The presented European multicenter study describes an optimized treatment and follow-up protocol for the de novo breast reconstruction after total mastectomy by lipotransfer alone.Methods: A retrospective European multicenter trial included 135 procedures on 28 (35 breasts postmastectomy patients (mean 52.4 years. All women were treated with the water-jet assisted fat grafting method (BEAULI™ combined with additional procedures (NAC reconstruction, contralateral mastoplasty and evaluated with at least 6 months follow-up (mean 2.6 years. Sonography or mammography, clinical examination, patient questionnaire (10-point Likert scale and digital photographs were carried out.Results: On average the patients received 4 to 6 procedures each with a single volume of 159 ml (±61 ml over 21 months (range 9 months to 2.5 years. In total 1,020 ml (±515 ml fat were grafted till a complete breast reconstruction was achieved. Irradiated patients needed a significantly higher volume than non-irradiated (p<0.041. Main treatment complications were liponecrosis (2.59%, infection (0.74% and granuloma (0.74%. Patient satisfaction was overall high to very high (96% and confirmed the good aesthetic results (68% and the natural softness, contour and shape of the reconstructed breast.Conclusions: A complete breast reconstruction with large volume fat grafting is alternatively possible to standard techniques in selected cases. It takes at least 4 to 6 lipotransfers in the course of 2 years. Patients with prior radiotherapy may require even up to 8 sessions over nearly 3 years of treatment.

  4. Natural orifice transluminal endoscopic wedge hepatic resection with a water-jet hybrid knife in a non-survival porcine model

    Institute of Scientific and Technical Information of China (English)

    Hong Shi; Sheng-Jun Jiang; Bin Li; Deng-Ke Fu; Pei Xin; Yong-Guang Wang

    2011-01-01

    AIM:To explore the feasibility of a water-jet hybrid knife to facilitate wedge hepatic resection using a natural orifice transluminal endoscopic surgery (NOTES) approach in a non-survival porcine model.METHODS:The Erbe Jet2 water-jet system allows a needleless,tissue-selective hydro-dissection with a preselected pressure.Using this system,wedge hepatic resection was performed through three natural routes (trans-anal,trans-vaginal and trans-umbilical) in three female pigs weighing 35 kg under general anesthesia.Entry into the peritoneal cavity was via a 15-mm incision using a hook knife.The targeted liver segment was marked by an APC probe,followed by wedge hepatic resection performed using a water-jet hybrid knife with the aid of a 4-mm transparent distance soft cap mounted onto the tip of the endoscope for holding up the desired plane.The exposed vascular and ductal structures were clipped with Endoclips.Hemostasis was applied to the bleeding cut edges of the liver parenchyma by electrocautery.After the procedure,the incision site was left open,and the animal was euthanized followed by necropsy.RESULTS:Using the Erbe Jet2 water-jet system,transanal and trans-vaginal wedge hepatic resection was successfully performed in two pigs without laparoscopic assistance.Trans-umbilical attempt failed due to an unstable operating platform.The incision for peritoneal entry took 1 min,and about 2 h was spent on excision of the liver tissue.The intra-operative blood loss ranged from 100 to 250 mL.Microscopically,the hydro-dissections were relatively precise and gentle,preserving most vessels.CONCLUSION:The Erbe Jet2 water-jet system can safely accomplish non-anatomic wedge hepatic resection in NOTES,which deserves further studies to shorten the dissection time.

  5. Testing of Alternative Abrasives for Water-Jet Cutting at C Tank Farm

    Energy Technology Data Exchange (ETDEWEB)

    Krogstad, Eirik J.

    2013-08-01

    Legacy waste from defense-related activities at the Hanford Site has predominantly been stored in underground tanks, some of which have leaked; others may be at risk to do so. The U.S. Department of Energy’s goal is to empty the tanks and transform their contents into more stable waste forms. To do so requires breaking up, and creating a slurry from, solid wastes in the bottoms of the tanks. A technology developed for this purpose is the Mobile Arm Retrieval System. This system is being used at some of the older single shell tanks at C tank farm. As originally planned, access ports for the Mobile Arm Retrieval System were to be cut using a high- pressure water-jet cutter. However, water alone was found to be insufficient to allow effective cutting of the steel-reinforced tank lids, especially when cutting the steel reinforcing bar (“rebar”). The abrasive added in cutting the hole in Tank C-107 was garnet, a complex natural aluminosilicate. The hardness of garnet (Mohs hardness ranging from H 6.5 to 7.5) exceeds that of solids currently in the tanks, and was regarded to be a threat to Hanford Waste Treatment and Immobilization Plant systems. Olivine, an iron-magnesium silicate that is nearly as hard as garnet (H 6.5 to 7), has been proposed as an alternative to garnet. Pacific Northwest National Laboratory proposed to test pyrite (FeS2), whose hardness is slightly less (H 6 to 6.5) for 1) cutting effectiveness, and 2) propensity to dissolve (or disintegrate by chemical reaction) in chemical conditions similar to those of tank waste solutions. Cutting experiments were conducted using an air abrader system and a National Institute of Standards and Technology Standard Reference Material (SRM 1767 Low Alloy Steel), which was used as a surrogate for rebar. The cutting efficacy of pyrite was compared with that of garnet and olivine in identical size fractions. Garnet was found to be most effective in removing steel from the target; olivine and pyrite were less

  6. Construção de um sistema simples e compacto de recirculação d'água sob pressão para trompa d'água Construction of a simple and compact system to recirculate water under pressure using a water-jet aspira tor pump

    Directory of Open Access Journals (Sweden)

    Dennis de Oliveira Imbroisi

    2009-01-01

    Full Text Available Vacuum pumps are very useful in physical, chemical and biological experiments. In this communication it is described the design of a compact and low cost water recirculating system employing a water-jet aspirator pump as the vacuum source. The system requires only a water pump, water-jet aspirator pump, commercial PVC water tubes and a drain connection.

  7. 水切割机器人路径规划方法%Path planning method of water-jet cutting robot

    Institute of Scientific and Technical Information of China (English)

    王玫; 孟正大

    2012-01-01

    以汽车内饰件切割路径优化为研究对象,提出了一种改进禁忌表蚁群算法,实现优化排序.根据水切割过程特点和工艺要求,进行了水切割路径规划问题分析与建模,设计了改进的禁忌表,利用分层思想将禁忌表划分为3段:内部小环段、内部大环段和外部轮廓段,各段的优先级依次降低,并确定了与此相应的禁忌表的更新规则.在此基础上,给出了基于改进禁忌表蚁群算法的水切割路径优化排序方法,对轮廓切割顺序和各轮廓起始点选择同时进行优化.仿真与实验结果表明,改进禁忌表蚁群算法是可行、有效的,可大大缩短水切割机器人的示教编程时间,显著提高水切割作业的效率和质量.%Taking the optimization of path planning of cutting automotive interior ornament as the research object, an improved tabu list based ant colony algorithm is presented to achieve cutting sequence optimization. According to the characteristics and technology demands of the water-jet cutting process, water-jet cutting path planning problem was analyzed and modeled. Taking advantage of the hierarchy principle, an improved tabu list was designed, which was divided into three sections : interior small loop, interior large loop, exterior outline section, and their priority reduces successively. Corresponding updating rules of the tabu list were proposed. The water-jet cutting path planning method based on the improved ant colony algorithm was proposed with which the cutting sequence of outlines and selection of starting point for cutting every outline are optimized simultaneously. Simulation and experimental results show that the improved tabu list based ant colony algorithm is feasible and effective. The teaching programming time of water-jet cutting robots can be shorten greatly, efficiency and quality of water-jet cutting jobs can be raised evidently.

  8. Matching of Ship,Waterjet,Propeller and Engine for Hybrid Propulsion Ship%混合推进船舶"船-泵+桨-机"匹配方法研究

    Institute of Scientific and Technical Information of China (English)

    刘祥珺

    2011-01-01

    为提高混合推进船舶推进系统的性能,分析了"船-泵+桨-机"的匹配方法.介绍了"船-桨-机"与"船-泵-机"的匹配方法、思路与步骤,着重研究"船-泵+桨-机"匹配中的泵、桨负载分配对推进性能的影响.以调距桨特性曲线与喷水推进推力曲线进行混合推进舰船的快速性计算,螺旋桨重载降低推进效率,喷水推进重载容易产生空化.为避免喷水推进泵产生空化,调距桨的螺距、转速可调范围变窄.%A method is presented to match hull, waterjet, propeller and engine designs to improve the performance of hybrid propulsion system. The methods, clews and procedures for hull-propeller-engine and hull-waterjet-engine matching are described first. Load distribution of propeller, waterjet and its influences on propulsion performance of hybrid propulsion system is specially researched. Controllable pitch propeller's characteristics curves and waterjet propulsion thrust curves are used to predict the speed of hybrid propulsion ship. Propulsive efficiency would be reduced when propeller is overloaded and cavitation would occur when waterjet propulsion is overloaded in hybrid propulsion system. Operation range of CPP's pitch and rotation speed is limited in order to avoid waterjet propulsion pump cavitation.

  9. On the fatigue behavior of medical Ti6Al4V roughened by grit blasting and abrasiveless waterjet peening.

    Science.gov (United States)

    Lieblich, M; Barriuso, S; Ibáñez, J; Ruiz-de-Lara, L; Díaz, M; Ocaña, J L; Alberdi, A; González-Carrasco, J L

    2016-10-01

    Flat fatigue specimens of biomedical Ti6Al4V ELI alloy were surface-processed by high pressure waterjet peening (WJP) without abrasive particles using moderate to severe conditions that yield roughness values in the range of those obtained by commercial grit blasting (BL) with alumina particles. Fatigue behavior of WJP and BL specimens was characterized under cyclical uniaxial tension tests (R=0.1). The emphasis was put on a comparative analysis of the surface and subsurface induced effects and in their relevance on fatigue behavior. Within the experimental setup of this investigation it resulted that blasting with alumina particles was less harmful for fatigue resistance than abrasiveless WJP. BL specimens resulted in higher subsurface hardening and compressive residual stresses. Specimens treated with more severe WJP parameters presented much higher mass loss and lower compressive residual stresses. From the analysis performed in this work, it follows that, in addition to roughness, waviness emerges as another important topographic parameter to be taken into account to try to predict fatigue behavior. It is envisaged that optimization of WJP parameters with the aim of reducing waviness and mass loss should lead to an improvement of fatigue resistance.

  10. 基于CFD的船舶喷水推进器优化设计%Waterjet optimal design based on CFD technology

    Institute of Scientific and Technical Information of China (English)

    常书平; 王永生; 丁江明; 聂沛军

    2013-01-01

    The important application of computational fluid dynamics (CFD) for marine waterjet performance analysis, optimal design and propulsion characteristic prediction was introducted. The solution domain of waterjet was defined and meshed by hexagonal structured grids. Turbulence effects were taken into account by using shear stress transport turbulent model. This model was applied to a newly designed waterjet pump on base of grid density independence examined. Several qualitative indexes and quantitative ones were adopted to evaluate the diffuser’s rectifying performance and the intake duct’s flow-delivering characters. Some reasonable suggestions for optimal design were provided. The flow field of hull and waterjet was sim-ulated on the base of every component had a good work. Area-integration method was employed to deduce the thrust character, which could make certain the ship speed and guarantee a successful outcome.%  介绍了计算流体力学(CFD)作为一种先进手段在喷水推进器水力性能分析、结构优化设计和推进性能检验中的重要应用。界定了喷水推进器数值计算域,采用结构化网格进行空间离散,选择剪切应力输运湍流模型进行数值计算。在进行了网格无关性分析的基础上,计算了某新型喷水推进泵的外特性,并采用多种定性和定量指标对导叶的整流效果和进水流道的引流性能进行评估,并进行了合理的优化改进。在各部件性能优良的基础上,对“船+泵”流场进行整体计算,通过壁面积分法求取喷水推进器产生的有效推力进行船舶快速性预报。 CFD技术的应用为喷水推进器最终设计成功提供了有力保障。

  11. Technology of Water-jet and Its Application in Medicine%水刀技术及其在医学领域的应用

    Institute of Scientific and Technical Information of China (English)

    郭新; 张西正; 徐晓莹; 郭春; 陈明东; 黄跃青; 崔智慧

    2009-01-01

    The technology of water-jet is an advanced technology of cold cutting which is widely used in industry, espe-cially in the cutting of metal, glass, ceramics and paper. Its character and classification are introduced, especially basic prineiple, development and application. The technology of water-jet will paly an important role in medicine.%水刀技术是一项先进的冷切割技术,在工业上应用十分广泛,主要用于切割金属、玻璃陶瓷和纸等.由于其选择性和保护性切割等优点,被引入医学领域并应用于临床.简述了其分类、特点,着重论述了医用水刀的基本原理、发展及其应用,指出水刀技术在医学领域必将发挥更为重要的作用.

  12. Simultaneous Independent Multi-Weft Detector Applied to Water-Jet Looms%喷水织机用多纬同时分别检测装置

    Institute of Scientific and Technical Information of China (English)

    张振奇; 程玮燕

    2001-01-01

    喷水织机多纬同时引入时的织造,只有在纬丝全部同时检测时才能保证产品的质量,提高生产效率;但目前大部分织机上没有此检测装置。文章在对喷水织机原有纬丝检测装置的结构进行全面分析之后,结合其他无梭织机的纬丝检测装置的结构特点,设计了一种利用纺丝机上的感丝器进行检测的装置,经试用,安全可靠,造价低廉,不失为一种有意义的探索,可供其他无梭织机借鉴。%During multi-weft weaving by water-jet loom, only all wefts aresimultaneously detected, can the product quality and high productivity be ensured. However, such detecting devices are unavailable for most of current looms. Through thorough analyses on the structure of the existing weft detectors for water-jet loom and in combination with the structural features of weft detectors for other shuttleless looms, a detecting device is designed on the basis of the yarn detector of spinning machine. It proves to be safe, reliable and low in cost through trial application, offering reference for other shuttleless looms.

  13. 多喷嘴射水式喷射器加热性能分析%Heating performance analysis of multi-nozzle water-jet steam ejector

    Institute of Scientific and Technical Information of China (English)

    童明伟; 蔡琴; 白秀娟

    2011-01-01

    This paper developes a heating coefficient model to study the heating performance of multi-nozzle water-jet steam ejector. It analyzes the factors of heating performance, and explores the relationships between the heating performance and different operating parameters theoretically and experimentally. The results show that the heating performance of multi-nozzle water-jet steam ejector is very good. The heating coefficient decreases with the increase of the inlet water temperature, and increases with the increase of the steam pressure and ejecting coefficient. The relationships between heating performance of ejector and different operating parameters by calculation and experiment are in good agreement.%为研究多喷嘴射水式喷射器的加热性能,提出了分析喷射器加热系数的计算模型,对喷射器加热性能的影响因素进行了分析,并根据理论分析和实验数据得出了不同运行参数对其加热性能的影响规律.研究结果表明,多喷嘴射水式喷射器具有很好的加热性能,喷射器的加热系数随入口水温的升高而减小,随蒸汽压力和引射系数的升高而增大,并且计算和实验得到的各运行参数对喷射器加热性能的影响规律是基本一致的.

  14. The research and manufacture of numerical control abrasive water-jet machine tool%磨料水射流数控机床的研究与开发

    Institute of Scientific and Technical Information of China (English)

    贾明峰; 俞涛; 方明伦; 林金生

    2001-01-01

    This paper introduces application and foreground of abrasive water jet, and introduces general structure and working principle of CNC abrasive water-jet machine tool.%介绍了磨料水射流技术广泛的应用及前景,并详细地介绍了磨料水射流数控切割机床的总体结构、工作原理和机构设计。

  15. 高压水射流冲击刚壁压力分布规律研究%Experimental Research of Impact Force Distribution on Rigid Wall by High Pressure Waterjet

    Institute of Scientific and Technical Information of China (English)

    刘智谋; 毛桂庭; 柯熠; 欧阳邓培

    2016-01-01

    为了探讨高压纯水射流和高压磨料射流冲击刚壁时射流冲击压力的分布规律,利用建立的专用测力工作台,研究了射流方向与刚壁成90°角时冲击压力的分布规律及靶距、系统工作压力对冲击压力的影响,并对磨料射流的强化效果进行了分析。结果表明:射流冲击力随径向距离的增加急速降低,是一非单调递减阶梯函数,连接各阶中心冲击力值,可视其为具非单调负指数下降规律。在靶距不变的情况下,纯水射流和磨料射流,其中心(最高压力)位置的冲击压力和系统压力呈正相关。%For exploring the distribution of impact force on rigid wall by pure waterjet and abrasive jet, the distribution of impact force with waterjet cutting angle at a 90° angle to the rigid wall, and effects on the impact force by the distance of nozzle from the rigid wall and water pressure available for the waterjet system were all tested with a specific force⁃measurement table, and the intensifying effect achieved by abrasive jetting was also analyzed. It is found that impact force of waterjet decreases rapidly with the increasing of radial distance, as a non⁃monotonically decreasing step function, connecting the central position of workbench and following a non⁃monotonic negative exponential decreasing rule. With the same distance between the nozzle and rigid wall for both pure waterjet and abrasive jet, the central position ( with the highest pressure) correlates positively with the system pressure.

  16. An Electrosurgical Endoknife with a Water-Jet Function (Flushknife) Proves Its Merits in Colorectal Endoscopic Submucosal Dissection Especially for the Cases Which Should Be Removed En Bloc

    Science.gov (United States)

    Takeuchi, Yoji; Ishihara, Ryu; Iishi, Hiroyasu; Hanaoka, Noboru; Higashino, Koji; Uedo, Noriya

    2013-01-01

    Background. Previously, we reported that the Flushknife (electrosurgical endoknife with a water-jet function) could reduce the operation time of colorectal endoscopic submucosal dissection (ESD) however, suitable situation for the Flushknife was obscure. This subgroup analysis of a prospective randomized controlled trial was aimed to investigate the suitable situation for the Flushknife. Methods. A total of 48 superficial colorectal neoplasms that underwent ESD using either the Flexknife or the Flushknife in a referral center were enrolled. The differences of operation time between the Flexknife and the Flushknife groups in each subgroup (tumor size, location, and macroscopic type) were analyzed. Results. Median (95% CI) operation time calculated using survival curves was significantly shorter in the Flushknife group than in the Flexknife group (55.5 min [41, 78] versus 74.0 [57, 90] min; P = 0.039, Hazard Ratio HR: 0.53; 95% CI (0.29–0.97)). In particular, the HR in patients with laterally spreading tumors-nongranular type (LST-NG) in the Flushknife group was significantly smaller than in the Flexknife group (HR: 0.165→0.17; 95% CI (0.04–0.66)). There was a trend of decreasing HRs according to larger lesion size. Conclusions. The Flushknife proved its merits in colorectal ESD especially for the lesions which should be removed en bloc (LST-NG and large lesion). PMID:24174933

  17. Fragmentation of bile duct stones: a prospective systematic in vitro evaluation of argon plasma coagulation, cryotechnology, and water-jet technology.

    Science.gov (United States)

    Eickhoff, A; Koberstein, S; Rothsching, M; Gemmel, C; Eickhoff, J C; Riemann, J F; Enderle, M D

    2009-08-01

    Choledocholithiasis is a common disease in the West. Lithotripsy by mechanical methods using baskets and by laser or electrohydraulic methods varies in effectiveness. With argon plasma coagulation (APC), high temperatures are used for devitalization and fragmentation; cryogenic techniques use the selective controlled application of freeze-thaw cycles to devitalize pathological tissue; and the dissecting water jet exploits the high pressure action of a thin laminar jet. We aimed to assess the feasibility and effectiveness of APC, cryotechnology, and the dissecting water jet as options for the fragmentation of bile duct stones. In an in vitro feasibility study, we evaluated the fragmentation of 120 bile duct stones treated with the three methods. Primary measures were assessment of the fragmentation rate, fragmentation effect, and energy application for each technology. Fragmentation was seen in only 10 % of stones treated cryogenically using liquid nitrogen. APC at a power setting of 30 - 50 W fragmented all the cholesterol stones, but results with hard pigment stones were unsatisfactory even at high energies of a 100 W setting and long application time. Using the water jet, all 40 stones (100 %) were cracked effectively and completely with a pressure of 10 - 50 bar. In this feasibility study, the first of its kind, only the water-jet device demonstrated efficient fragmentation of large bile duct stones in vitro. APC and cryotechnology are not suitable for the treatment of bile duct stones; the fragmentation rate with these methods was inadequate.

  18. An Electrosurgical Endoknife with a Water-Jet Function (Flushknife Proves Its Merits in Colorectal Endoscopic Submucosal Dissection Especially for the Cases Which Should Be Removed En Bloc

    Directory of Open Access Journals (Sweden)

    Yoji Takeuchi

    2013-01-01

    Full Text Available Background. Previously, we reported that the Flushknife (electrosurgical endoknife with a water-jet function could reduce the operation time of colorectal endoscopic submucosal dissection (ESD however, suitable situation for the Flushknife was obscure. This subgroup analysis of a prospective randomized controlled trial was aimed to investigate the suitable situation for the Flushknife. Methods. A total of 48 superficial colorectal neoplasms that underwent ESD using either the Flexknife or the Flushknife in a referral center were enrolled. The differences of operation time between the Flexknife and the Flushknife groups in each subgroup (tumor size, location, and macroscopic type were analyzed. Results. Median (95% CI operation time calculated using survival curves was significantly shorter in the Flushknife group than in the Flexknife group (55.5 min [41, 78] versus 74.0 [57, 90] min; , Hazard Ratio HR: 0.53; 95% CI (0.29–0.97. In particular, the HR in patients with laterally spreading tumors-nongranular type (LST-NG in the Flushknife group was significantly smaller than in the Flexknife group (HR: 0.1650.17; 95% CI (0.04–0.66. There was a trend of decreasing HRs according to larger lesion size. Conclusions. The Flushknife proved its merits in colorectal ESD especially for the lesions which should be removed en bloc (LST-NG and large lesion.

  19. The use of water-jetting technology in prostheses revision surgery-first results of parameter studies on bone and bone cement.

    Science.gov (United States)

    Honl, M; Rentzsch, R; Müller, G; Brandt, C; Bluhm, A; Hille, E; Louis, H; Morlock, M

    2000-01-01

    Water-jet cutting techniques have been used in industrial applications for many different materials. Recently these techniques have been developed into a revolutionary cutting tool for soft tissues in visceral surgery. The present study investigates the usage of this cutting technology for the revision surgery of endoprostheses. In the first part of the study, samples of bovine bone and acrylic bone cement (PMMA) were cut using an industrial jet cutting device with pure water. Below 400 bar, only PMMA was cut; above 400 bar, bone was also cut, but only pressures above 800 bar resulted in clinically useful rates of material removal (cut depth 2. 4 mm at 10 mm/min traverse speed). In the second part of the study, the effect of adding biocompatible abrasives to the water in order to reduce the required pressure was investigated, resulting in a significantly higher removal of material. At 600 bar, PMMA was cut 5. 2 mm deep with plain water and 15.2 mm deep with added abrasives. The quality of the cuts was increased by the abrasive. Though there was no clear selectivity between bone and PMMA any more, the rate of material removal at similar pressures was significantly higher for PMMA than for bone (600 bar: 1.6 mm cut depth for bone samples, 15.2 mm for PMMA). The measured cut depths with either method were not influenced by a change of the cutting direction with respect to the main direction of the osteons in the bone. However, a reduction of the jet surface angle (90 degrees to 23 degrees ) resulted for bone in a significantly lower cut depth at 600 bar (plain water: 0.62 mm vs. 0.06 mm; abrasive: 1.61 mm vs. 0.60 mm). The laboratory experiments indicate that abrasive water jets may be suitable for cutting biomaterials like bone and bone cement.

  20. Experiments on Deflecting & Oscillating Waterjet

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new type jet,the oscillating & deflecting jet ,is put forward and its oscillating and deflecting characteristics are investigated.The nozzle of the self-oscillating & deflecting water jet consists of an upstream nozzle,a downstream nozzle,an oscillating chamber and two switches,It is experimentally shown that the deflective angle may reach 9.53 degeree,the generated pressure fluctuation is very regular and the jet can efficiently increase the ability for bradking and cutting by eliminating the water cushion effect associated with a continuous jet.

  1. Development of Waterjet Propulsion Unit

    Science.gov (United States)

    1985-03-01

    Figure I shows the configuration of the proposed propulsion system in the aft end of an LVTP-7A1. A 20-inch diameter impeller is to be housed in a...16A the straamlne0 1 ig. 30Reato between vltys coff "scienw C+ andrust r atio o nd no l ocit in 09- 046 Anlyi to 12e e1Pople 16 is 20 s 24 262n3 Fig

  2. SPH和FEM耦合法模拟磨料水射流中单磨粒加速过程%Numerical simulation of single particle acceleration process by SPH coupled FEM for abrasive water-jet cutting

    Institute of Scientific and Technical Information of China (English)

    王建明; 余丰; 刘飞宏; 张刚

    2011-01-01

    针对Eulerian和ALE(arbitrary lagriange eulerian)方法仿真研究磨料水射流喷嘴中磨料粒子加速过程的局限性,提出采用SPH(smoothed particle hydrodynamics)耦合FEM(finite element method)的方法研究后混式磨料水射流喷嘴中低速磨料粒子在高速水射流作用下的流体动力学特性和磨粒加速后撞击靶材的全过程。水用SPH建模,磨料粒子、喷嘴和工件用FEM建模,通过接触算法实现SPH和FEM的耦合以模拟后混式磨料水射流加工的全过程。仿真研究了磨粒和水在喷嘴中各自的速度变化过程;单磨粒在喷嘴中的运动轨迹;不同直径的磨料粒子在不同水压作用下的速度变化过程;不同直径的磨粒在不同直径的混合管中出口速度的变化规律;磨料粒子在工件上的撞击深度。通过与相关实验及理论数据的比较,验证了仿真模型和结果的正确性。%The existing Eulerian and arbitrary Lagrange Eulerian(ALE) grid-based algorithms were used to study the hydrodynamic characteristics of pre-mixed abrasive water-jet(AWJ) in a cutting head.Smooth particle hydrodynamics(SPH) coupled with the finite element method(FEM) algorithm was adopted to establish a new AWJ model,by which the abrasive particle could enter into the mixing chamber in a low velocity and could be accelerated in the focus tube by a high-speed water-jet from the orifice.SPH particles were used to model the high-speed water-jet and the FEM was applied to model the discrete abrasive particle,cutting head and workpiece.Consequently,the evolution of abrasive and water-jet velocities along the focus tube was analyzed and the trajectory of a single abrasive particle in the focus tube was sighted.Relationships between abrasive particle velocities and different water pressures were studied and the rule of outlet velocities of abrasive particle vs.dimensionless ratio of diameter was conducted.The penetration depth caused by a single

  3. 前混式磨料水射流弹药切割机的研究与开发%Research and Development of Premixing Abrasive Water-jet Cutting Machine for Ammunition Destruction

    Institute of Scientific and Technical Information of China (English)

    祝爽; 吕游; 李湘文

    2012-01-01

    In order to achieve the disintegration of dangerous ammunitions,an ammunition cutting machine based on premixing abrasive water-jet technology was developed.Through the system design,abrasive supply system study,special actuator development,some problems in application of the technology have been solved.The field experiment showed that the developed cutting machine could safely,economically,environment-friendly and flexibly cut dangerous ammunitions,has been included in the formal army equipments.%为了解决危险弹药解体问题,研制了基于前混式磨料水射流技术的弹药切割机,通过对系统方案设计、磨料供应系统研究、专用执行机构的开发,解决了技术应用中存在的问题,现场试验证明,研制设备达到了安全、可靠、经济、环保、灵活切割危险弹药的目的,已列入部队正式装备。

  4. 喷水推进器进水流道参数化设计方法%Research on the parametric design of an inlet duct found in a marine waterjet

    Institute of Scientific and Technical Information of China (English)

    丁江明; 王永生

    2011-01-01

    为了提高喷水推进器进水流道的设计水平,改善其水动力性能、缩短设计周期、降低设计费用,研究了进水流道的参数化设计方法.在该方法中,进水流道的三维几何结构采用11个动态关联的控制参数定量描述.改变这些控制参数的值可自动调整流道的三维空间形状,实现流道几何的快速建模.在此基础上,利用计算流体力学方法对进水流道及船尾流场进行数值计算,用进水流道的出流均匀度、流动分离程度、空化程度、流动损失程度以及变工况适用性等多项指标对进水流道的流体动力性能进行综合评估.流道三维几何结构的参数化建模和综合流体动力性能的数值模拟这2个过程迭代运用,可实现进水流道的优质、快速设计.%In order to satisfactorily design an inlet duct found in marine waterjets in a way that economically uses time and money, a parametric design method was investigated in this article. The 3-D geometry of the inlet duct was characterized and created by eleven governing parameters which were incident with one another. Its shape could be modified automatically by turning the value of the governing parameters. The viscous flow in regions around the inlet duct and stern was simulated by means of a computational fluid dynamics code. The hydrodynamic performance of the inlet duct can be evaluated in the round according to flow uniformity at the duct outlet, flow separation, cavitations, flow loss inside the duct, and the applicability to various working conditions. Multiple iterations between the parametric modification of the geometry and CFD simulation of the flow field can quickly result in an excellent inlet duct design.

  5. Modeling of Cavitating Flow through Waterjet Propulsors

    Science.gov (United States)

    2015-02-18

    break down due to massive suction side flow separation (stall). In Figure 3, photographs from tunnel testing and computed results are shown. The...128, pp. 1308-1323. Mishra C. & Peles, Y. (2005) "Cavitation in flow through a micro- orifice inside a silicon micro- channel,’ Phvs. Fluids 17

  6. Wear characterization of abrasive waterjet nozzles and nozzle materials

    Science.gov (United States)

    Nanduri, Madhusarathi

    Parameters that influence nozzle wear in the abrasive water jet (AWJ) environment were identified and classified into nozzle geometric, AWJ system, and nozzle material categories. Regular and accelerated wear test procedures were developed to study nozzle wear under actual and simulated conditions, respectively. Long term tests, using garnet abrasive, were conducted to validate the accelerated test procedure. In addition to exit diameter growth, two new measures of wear, nozzle weight loss and nozzle bore profiles were shown to be invaluable in characterizing and explaining the phenomena of nozzle wear. By conducting nozzle wear tests, the effects of nozzle geometric, and AWJ system parameters on nozzle wear were systematically investigated. An empirical model was developed for nozzle weight loss rate. To understand the response of nozzle materials under varying AWJ system conditions, erosion tests were conducted on samples of typical nozzle materials. The effect of factors such as jet impingement angle, abrasive type, abrasive size, abrasive flow rate, water pressure, traverse speed, and target material was evaluated. Scanning electron microscopy was performed on eroded samples as well as worn nozzles to understand the wear mechanisms. The dominant wear mechanism observed was grain pullout. Erosion models were reviewed and along the lines of classical erosion theories a semi-empirical model, suitable for erosion of nozzle materials under AWJ impact, was developed. The erosion data correlated very well with the developed model. Finally, the cutting efficiency of AWJ nozzles was investigated in conjunction with nozzle wear. The cutting efficiency of a nozzle deteriorates as it wears. There is a direct correlation between nozzle wear and cutting efficiency. The operating conditions that produce the most efficient jets also cause the most wear in the nozzle.

  7. Development of underwater cutting system by abrasive water-jet

    Science.gov (United States)

    Demura, Kenji; Yamaguchi, Hitoshi

    1993-09-01

    The technology to cut objects in the ocean's depths with abrasive water jets was examined for possible application in view of the greater water depths and sophistication involved in work on the ocean floor today. A test model was developed to study this technology's safety and practicability. The test model was designed for use at great water depths and has functions and a configuration that are unlike equipment used on land. A continuous, stable supply of abrasive is a distinctive design feature. In land applications, there had been problems with plugged tubes and an uneven supply. For this reason, the abrasive was converted to slurry form, and a continuous pressurized tube pump system was adopted for supply to the nozzle head. Also, a hydraulic motor that does not employ oil or electric power was used to provide an underwater drive that is environment-friendly. The report outlines the technology's general design concept including its distinctive functions and its configuration for use at great depths, and the report provides great detail on the equipment.

  8. Experiences with waterjet hydrosurgery system in wound debridement

    Directory of Open Access Journals (Sweden)

    Gurunluoglu Raffi

    2007-05-01

    Full Text Available Abstract Background Recently, a new device, the Versajet™, involving "Hydrosurgery Technology" which combines lavage and sharp debridement instrumentation has been described for soft tissue debridement. Methods The Versajet™ Hydrosurgery System utilizes a reusable power console with foot pedal activation, disposable handpiece and tubing assembly in conjunction with sterile saline and standard waste receptacle. The purpose of this paper is to report our experiences with this instrument in debridement of a variety of wounds prior to final reconstructive surgery. Technical details and pitfalls are discussed to facilitate clinical use. Results Efficient, safe and fast debridement was achieved in all patients using the hydrosurgery system. The actual time the hydrosurgery system was used for debridement averaged as 15.5 minutes. In ten patients, an adequately debrided wound bed was achieved with a single operative procedure, in four patients; two stages were required prior to reconstructive surgery. In one patient with recurrent sacral-iscial pressure sore, two debridements were carried out followed by long term vacuum assisted closure. The postoperative course was uneventful in all patients, but in three with a minor breakdown of the skin graft, which eventually healed with no surgical intervention. Conclusion As a result of our clinical experience, the Versajet™ enables surgeon to precisely target damaged and necrotic tissue and spare viable tissue. This modality may be a useful alternative tool for soft tissue debridement in certain cases. However, further studies are required to investigate its cost-effectiveness in wound management.

  9. EXPERIMENTAL AND NUMERICAL INVESTIGATION OF BUBBLE AUGMENTED WATERJET PROPULSION

    Institute of Scientific and Technical Information of China (English)

    WU Xiongjun; CHOI Jin-Keun; SINGH Sowmitra; HSIAO Chao-Tsung; CHAHINE Georges L.

    2012-01-01

    This contribution presents experimental and numerical investigations of the concept jet propulsion augmentation using bubble injection.A half-3D (D-shaped cylindrical configuration to enable optimal visualizations) divergent-convergent nozzle was designed,built,and used for extensive experiments under different air injection conditions and thrust measurement schemes.The design,optimization,and analysis were conducted using numerical simulations.The more advanced model was based on a two-way coupling between an Eulerian description of the flow field and a Lagrangian tracking of the injected bubbles using our Surface Averaged Pressure (SAP) model.The numerical resultscompare very favorably with nozzle experiments and both experiments and simulations validation the thrust augmentation concept.For a properly designed nozzle and air injection system,air injection produces net thrust augmentation,which increases with the rate of bubble injection.Doubling of thrust was measured for a 50% air injection rate.This beneficial effect remains at 50% after account for liquid pump additional work to overcome increased pressure by air injection.

  10. Prediction of Cavitating Waterjet Propulsor Performance Using a Boundary Element Method

    Science.gov (United States)

    2007-10-01

    Cavitation, September 11-15, 2006, Wageningen , The Netherlands. Kinnas, S.A., Choi, J.-K., Lee, H., Young, Y.L., Gu, H., Kakar, K. and Natarajan, S...inviscid component Propulsors and their Interaction interactive method", in CA V2006: Sixth International 13 Symposium on Cavitation, Wageningen , The

  11. Surface oxidation and phase transformation of the stainless steel by hybrid laser-waterjet impact

    Science.gov (United States)

    Weiss, L.; Aillerie, M.; Tazibt, A.; Tidu, A.

    2014-09-01

    Hybrid jets (laser guided by water jet) are commonly used in the area of microelectronics for cutting thin wafer plates and for the design of special pieces. In this context, the hybrid jet works with a low power and low pressure. Efforts are made to apply and to improve this hybrid technology for cutting thicker metallic materials. In order to facilitate this development, we have studied the effects induced by a water jet-laser system coupled to the same point on a metallic material. The pressure of the water jet is about 1 MPa and the power of the laser source is about 400 W, which is much higher than the actual hybrid jet power. As a result, in the case of 301 L steel plates, we have noticed the formation of a magnetite layer around the cut in accordance with the high temperature reactions between water and iron, but, surprisingly, in this case, the reaction is practically instantaneous. A small percentage of hematite also appears, from a secondary reaction of reduction of magnetite. By using different techniques (Raman spectroscopy, optical microscopy, SEM, XRD…) we have observed, firstly, that the width of the oxidized zone is proportional to the cutting speed and on the other hand, that there exists a phase transformation in a small heat-affected zone, consistent with the hybrid jets literature.

  12. OPTIMASI DENGAN ALGORITMA RSM-CCD PADA EVAPORATOR VAKUM WATERJET DENGAN PENGENDALI SUHU FUZZY PADA PEMBUATAN PERMEN SUSU (RSM-CCD Algorithm for Optimizing Waterjet Vacuum Evaporator Using Fuzzy Temperature Control in The Milk Candy Production

    Directory of Open Access Journals (Sweden)

    Yusuf Hendrawan

    2016-10-01

    Full Text Available Milk candy is a product which has to be produced under a high temperature to achieve the caramelization process. The use of vacuum system during a food processing is one of the alternatives to engineer the value of a material’s boiling point. The temperature control system and the mixing speed in machine that produce the milk candy were expected to be able to prevent the formation of off-flavour in the final product. A smart control system based on fuzzy logic was applied in the temperature control within the double jacket vacuum evaporator machine that needs stable temperature in the cooking process. The objective of this research is developing vacuum evaporator for milk candy production using fuzzy temperature control. The result in machine and system planning showed that the process of milk candy production was going on well. The parameter optimization of water content and ash content purposed to acquire the temperature point parameter and mixing speed in milk candy production. The optimization method was response surface methodology (RSM, by using the model of central composite design (CCD. The optimization resulted 90.18oC for the temperature parameter and 512 RPM for the mixing speed, with the prediction about 4.69% of water content and 1.57% of ash content. Keywords: Optimization, vacuum evaporator, fuzzy, milk candy, response surface methodology ABSTRAK Permen susu merupakan salah satu produk yang diolah dengan suhu tinggi untuk mencapai proses karamelisasi. Pengolahan pangan dengan sistem vakum merupakan salah satu alternatif untuk merekayasa nilai titik didih suatu bahan. Sistem pengendalian suhu serta kecepatan pengadukan pada mesin produksi permen susu diharapkan dapat mencegah terbentuknya partikel hitam (off-flavour pada produk akhir. Sistem kontrol cerdas logika fuzzy diaplikasikan dalam pengendalian suhu pada mesin evaporator vakum double jacket yang membutuhkan tingkat stabilitas suhu pemasakan permen susu. Tujuan dari penelitian ini adalah membuat rancang bangun evaporator vakum pada pembuatan permen susu dengan menggunakan pengendali suhu fuzzy. Hasil perancangan mesin dan sistem menunjukkan bahwa proses produksi permen susu dapat berlangsung dengan baik. Optimasi parameter kadar air dan kadar abu dilakukan untuk mendapatkan titik parameter suhu dan kecepatan pengadukan produksi permen susu yang optimum. Metode optimasi menggunakan response surface methodology (RSM model central composite design (CCD. Hasil optimasi didapatkan parameter suhu 90,18oC dan kecepatan pengadukan 512 RPM, dengan prediksi produk permen susu memiliki nilai kadar air 4,69% dan kadar abu 1,57%. Kata kunci: Optimasi, evaporator vakum, fuzzy, permen susu, response surface methodology

  13. Axial Waterjet (AxWJ) Model 5662 and Mixed-Flow Waterjet (MxWJ) Model 5662-1: Comparisons of Resistance and Model-Scale Powering with Propulsion Nozzle Designs

    Science.gov (United States)

    2007-12-01

    and yaw, but are free to pitch, heave, and roll. The location of each model tow point was approximately ship Station 5, parallel to, and at the same...MxWJ C5 NellH JOMOd GAlpeUJ3 U’) LO U-) ul U) U*) LO C4 ~ ~ 0% 0 oq c6 o 6- 6 0P U’) .. .. ... . lic C) U) COU o xo _ NU w UJ I4C V- T- (000 d4) GMO OAIG...C? Cf) N N - - 00 0) co - - 0~~ 0 * 0 0~ ~~ ~~~ 0r. 0 0 0 0 U)~~~~~~~Z .V - 0 ) C D LI V 1~CD (~vAld) GMO aAqell pepedd OW8j JOMOd PGJeA!Iea m) C%j

  14. The role of water-jet dissection in improving erectile function and urinary continence after nerve-sparing prostatectomy.

    Science.gov (United States)

    Glybochko, Peter V; Rapoport, Leonid M; Bezrukov, Eugene A; Sirota, Eugene S; Martirosyan, Gurgen A

    2017-08-01

    The aim of this study was to assess erectile function (EF) and urinary continence (UC) recovery after nerve-sparing retropubic radical prostatectomy (NS-RRPE) and nerve-sparing laparoscopic radical prostatectomy (NS-LRPE) depending on the neurovascular bundle (NVB) dissection technique used. Twenty-four hour pad test was used to assess the degree of postoperative UC 1, 6 and 12 months after the surgery. For the purpose of EF assessment, International Index of Erectile Function-5 (IIEF-5) questionnaire was used. In addition, EF recovery assessment included the time needed to achieve a successful sexual intercourse with or without Inhibitors Phosphodiesterase 5 (IPDE5). A successful sexual intercourse was defined as an ability to achieve a strong erection enough for penetration and maintain erection for a long time, throughout the intercourse. Assessment was performed before the surgery and 8 and 6 months after the surgery. In the patient group with BNS + water jet dissection (WJD), the IIEF-5 score was considerably higher 8 weeks after the surgery (by 2.8 points) (р = 0.02). In 6 months, the difference between the group become more significant and reached 3.5 points (p = 0.01). Three months after urethral catheter removal, majority (95%) of patients in the NS-RPE + WJD group had no urinary incontinence (UI). For standard NS-RPE, that figure was 87%. Mild stress UI was observed in 5% of patients after NS-RPE + WJD and in 13% of patients after NS-RPE. Six months after urethral catheter removal, no significant differences in UC assessment were observed in the two groups. The implementation of WJD of NVB in clinical practice has made it possible to considerably improve the quality of life for postoperative patients due to good outcomes in terms of early UC and EF recovery.

  15. How do jet time, pressure and bone volume fraction influence the drilling depth when waterjet drilling in porcine bone?

    Science.gov (United States)

    den Dunnen, Steven; Dankelman, Jenny; Kerkhoffs, Gino M M J; Tuijthof, Gabrielle J M

    2016-09-01

    Using water jets for orthopedic procedures that require bone drilling can be beneficial due to the absence of thermal damage and the always sharp cut. Previously, the influence of the water jet diameter and bone architectural properties on the drilling depth have been determined. To develop water jet instruments that can safely drill in orthopedic surgery, the impact of the two remaining primary factors were determined: the jet time (tjet [s]) and pressure (P [MPa]). To this end, 84 holes were drilled in porcine tali and femora with water jets using Ø 0.4mm nozzle. tjet was varied between 1, 3 and 5s and P between 50 and 70MPa. Drilling depths Lhole (mm), diameters Dhole (mm) and the volume of mineralized bone per unit volume (BV/TV) were determined with microCT scans. A non-linear regression analysis resulted in the predictive equation: Lhole= 0.22 * tjet(0.18) * (1.2-BV/TV) * (P-29) (R(2)=0.904). The established relation between the machine settings and drilling depth allows surgeons to adjust jet time and pressure for the patient׳s BV/TV to drill holes at a predetermined depth. For developers, the relation allows design decisions to be made that influence the dimensions, flexibility and accuracy of water jet instruments. For a pressure of 50MPa, the potential hole depth spread indicated by the 95% confidence interval is drilling can be applied in orthopedic surgery to drill holes in bone with controlled depth.

  16. Axial Waterjet (AxWJ) Model 5662: Hull Resistance and Model-Scale Powering with LDV Nozzle Design

    Science.gov (United States)

    2007-09-01

    6 M odel-Scale Rotor Forces: Ship Propulsion Point As Tested ........................................ 6 M odel-Scale Rotor Forces: Over and Under...Propulsion ................................................. 7 Model-Scale Rotor Forces: Estimated At Corrected Ship Propulsion Point...hull. The largest increase was measured at 30 knots, where the LDV nozzles increased the PE by 4.9%. Model-Scale Rotor Forces: Ship Propulsion Point

  17. Histologic effects of different technologies for dissection in endoscopic surgery: Nd:YAG laser, high frequency and water-jet.

    Science.gov (United States)

    Schurr, M O; Wehrmann, M; Kunert, W; Melzer, A; Lirici, M M; Trapp, R; Kanehira, E; Buess, G

    1994-01-01

    Precise cutting combined with reliable coagulation of the margins of the lesion is an important requirement for dissection techniques in endoscopic surgery. These requirements are met by the two most common ancillary energy sources applied for endoscopic dissection today, electrosurgery and "thermal lasers", mostly the Nd:YAG. For the comparison of the histological effects of monopolar and bipolar high frequency with the Nd:YAG laser an experimental in vitro and in vivo study has been performed. In order to evaluate the advantages of non thermal dissection for endoscopic procedures, a water jet cutting system was included in the in vitro study. In parenchymatous tissue the water jet was found to be the least traumatic technique, followed by bipolar high frequency, laser and monopolar high frequency. The water jet was not applicable for intestinal dissection since uncontrolled bloating of the rectal wall with uncontrolled disruption of the tissue layers occurred. A general disadvantage is that secure haemostasis in the line of incision is hard to achieve. In the microscopic comparison of the shape of the incision, the Nd:YAG laser produced the smoothest lesions with well-defined margins. The monopolar technique was more often associated with irregular and sometimes fissured margins. These results were confirmed in the in vivo part of the study (Transanal Endoscopic Microsurgery).

  18. Dermal microvasculature and tissue selective thinning techniques (ultrasound and water-jet) of short-time expanded skin in dogs.

    Science.gov (United States)

    Siegert, R; Danter, J; Jurk, V; Eggers, R; Krüger, S

    1998-01-01

    Certain reconstructive procedures, like auricular reconstructions, require thin and well-vascularized skin. The aims of this study were to analyze if the increased survival of expanded skin flaps was due to morphologic changes of the dermis, if thinning of short-time expanded skin was possible without harm to the microcirculation and if tissue selective cutting methods could be used to resect subcutaneous fat without damaging its vessels. Eighty-two 200-ml expanders were implanted into the trunk regions of 26 beagles and filled immediately with sterile saline. In the first series of experiments, the expansion was terminated after intervals of 0.5-5 weeks and dermal vessels were analyzed morphometrically. In the second series the expanded flaps were raised after 2 weeks and thinned solely surgically or with the additional use of an ultrasonic knife or with cutting by water jet. In contrast to sham flaps, the expanded skin showed only very few areas of necrosis and these were located superficially in most cases. The relative volume of the dermal vessels and their quantity showed a significant increase after the expansion. Additionally, the subcutaneous tissue could be thinned down to 0.4 mm with the water-jet-cutter. Findings demonstrated that the method used could create a well-vascularized skin flap of minimal thickness that could be very helpful for special reconstructive procedures.

  19. Thermal Investigation of Interaction between High-power CW-laser Radiation and a Water-jet

    Science.gov (United States)

    Brecher, Christian; Janssen, Henning; Eckert, Markus; Schmidt, Florian

    The technology of a water guided laser beam has been industrially established for micro machining. Pulsed laser radiation is guided via a water jet (diameter: 25-250 μm) using total internal reflection. Due to the cylindrical jet shape the depth of field increases to above 50 mm, enabling parallel kerfs compared to conventional laser systems. However higher material thicknesses and macro geometries cannot be machined economically viable due to low average laser powers. Fraunhofer IPT has successfully combined a high-power continuous-wave (CW) fiber laser (6 kW) and water jet technology. The main challenge of guiding high-power laser radiation in water is the energy transferred to the jet by absorption, decreasing its stability. A model of laser water interaction in the water jet has been developed and validated experimentally. Based on the results an upscaling of system technology to 30 kW is discussed, enabling a high potential in cutting challenging materials at high qualities and high speeds.

  20. TECHNIQUE AND SURGICAL OUTCOMES OF ANATOMICAL LIVER RESECTIONS FOR COLORECTAL CANCER LIVER METASTASES

    Directory of Open Access Journals (Sweden)

    D. V. Sidorov

    2013-01-01

    Full Text Available Technique and surgical outcomes of anatomical liver resections using ERBEJET2® water-jet dissector were described. Overall 98 patients with colorectal cancer liver metastases were included in this study. In 43 patients resections were performed using water-jet dissection technique. Water-jet dissection seems to be safe and effective technique for anatomical liver resections.

  1. Defense Technology Plan

    Science.gov (United States)

    1994-09-01

    solid waste evaporative treatment for * Supercritical water oxidation treatment ships liquid wastes for destruction of ships liquid - Alternative...Prcpulsion track and amphibious support over water waterjet drive vehicle 4 X current capability SDem•o reduced * Demo reduced length diameter, high...integral steering efficiency waterjet waterjets propulsors_ Future Vehicle * Complete FMBT user- * Demo a main battle FMBT Integration developer studies

  2. Research on hydrodynamic characteristics of axial waterjet pump with guide vane%加导叶轴流泵水动力特性研究

    Institute of Scientific and Technical Information of China (English)

    胡健; 黄胜; 王培生

    2008-01-01

    用数值方法计算了加导叶轴流泵的水动力特性.在质量守恒定理和动量守恒定理的基础上建立不可压缩流体的积分方程,以SIMPLE为基本算法,结合速度修正方程和压力修正方程,求解轴流泵的内部速度场和压力场,采用基于二方程雷诺数时均方程方法研究轴流泵的湍流模型.用数值方法建立轴流泵的三维数学模型,用混合网格布置方法提高计算精度.分析了不同流量下加导叶轴流泵器的流量和扬程、功率和效率的关系;研究了导叶对轴流泵水动力性能的影响.

  3. 论织物规格与喷水织机效率的关系%Relation between Fabric Specifications and Efficiency of Water-Jet Loom

    Institute of Scientific and Technical Information of China (English)

    陈超; 顾建华; 李春萍

    2001-01-01

    A success in the development of products should involve therequired fabric styles and weavability. Therefore, it is very important to know the relation between fabric specifications and loom efficiency. This paper quantitatively or qualitatively examines some essential factors for fabric specifications such as covering factor, fabric weave, warp and weft combination, loom efficiency and their relation, serving as a reference for prediction of loom efficiency in product design.%成功的产品开发既要使织物风格符合要求,又要有良好的织造性能,因此织物规格与织机效率的关系十分重要。文章定量或定性地讨论了织物规格的几个要素即织物紧度、织物组织与经纬组合与织机效率的关系,可供产品设计时预测织机效率作参考。

  4. 磨料水射流表面波模型%A model of surface waves of abrasive water-jet

    Institute of Scientific and Technical Information of China (English)

    胡俊伟; 陈义强; 王军

    2001-01-01

    In this paper,we describe the character of abrasive water-jetcutting and develop a model of surface wave.In this model establishes the relation between the surface wave Ry and the kerf depth h according to the influence to the surface wave by the changing of the kerf width,which can increase the precision of the model.The model can provide the convenience for the analysis to the cut characteristics.%对磨料水射流切割过程的特征进行了描述,并对射流切割形成的表面波纹建立了模型,该模型建立了表面波纹度Ry与射流切割深度h间的关系,同时,模型建立过程中还考虑到了切割宽度变化对表面波纹的影响,从而进一步增强了模型的准确性,该模型为进行切口质量分析提供了条件。

  5. 708所的新型喷水推进组合体

    Institute of Scientific and Technical Information of China (English)

    王立祥; 王泽群

    2000-01-01

    As a new typed thruster, water-jet thruster was successfully applied onboard of Shengli 221-a multi-tug ship for shallow sea in China at the end of 1980's and later it alsoo btained satisfaction on many other typed vessels. The successful installation onboard of the dredgers have showed that water-jet thruster may replace controllable pitch propeller. This paper details the structure, performances, features of the water-jet thruster, as well as the real applications onboard.

  6. Energy transfer during the hydroentanglement of fibres

    CSIR Research Space (South Africa)

    Moyo, D

    2012-10-01

    Full Text Available , and the resultant degree of fibre entanglement, determines the tensile strength of the nonwoven fabric as a consequence of the inter-fibre friction. Here, the relationship between hydroentangling energy from the waterjets and the changes it brings about... in the nonwoven fabric strength were studied. In the study, the energies of the waterjets transferred to every fabric sample as a function of the waterjet pressure, machine speed, machine efficiency and the web area weight were quantified, and the resultant...

  7. Influence of Outlet Guide Vanes upon Performances of Waterjet Axial-Flow Pump%后导叶对喷水推进轴流泵性能的影响

    Institute of Scientific and Technical Information of China (English)

    汤方平; 王国强

    2006-01-01

    通过三维紊流数值计算和模型试验研究后导叶对轴流泵整体性能的影响.计算和泵试验表明,基于RNG k-ε紊流模型的定常流动分析能有效预测高效区内的泵特性.叶轮和导叶之间的轴向间隙为0.1 D时,后导叶对叶轮性能几乎没有影响,后导叶主要以对叶轮出口水流的旋转动能的回收和水力损失的形式对泵的特性产生影响.通过后导叶设计工况的选择,可适应不同的应用要求,实现叶轮和后导叶优化配置的目的.%With the use of three-dimensional turbulence numerical simulation and model test,the influence of the outlet guide vanes (OGV) on the overall performances of the axial-flow pump is studied.The computational and experimental results indicate that the steady numerical simulation based on the RNG k-ε turbulence model can effectively predict the pump performances at the design flow rate. When the axial clearance between the impeller and the OGV is greater than 0.1D,the OGV almost has no influence on the performance of the impeller. The existence of OGV will recycle the rotating kinetic energy of the impeller outlet, and cause hydraulic losses at the same time. By selecting the design operation point of the OGV,the configuration between the impeller and the OGV can be optimized in order to satisfy user's requirements.

  8. Research on Harnessing Coal-dust Stained Yarn with Hydrodynamic Ultrasonic Water-jet Room%流体动力式超声喷水室治理"煤灰纱"研究

    Institute of Scientific and Technical Information of China (English)

    李刚; 黄翔

    2005-01-01

    介绍了传统喷水室用于去除微细粉尘的不足之处以及流体动力式超声波凝聚喷水室治理"煤灰纱"现象的原理.这种新方法能够充分利用原有喷水室,只需在原有基础上稍加改造即可,因此非常适合于纺织行业.

  9. Design and Research of the Premixed Abrasive Water-jet Cutting Machine%前混式磨料水射流切割机的设计与研究

    Institute of Scientific and Technical Information of China (English)

    张怀亮

    2001-01-01

    针对建筑物改造、装修时往往需要切割砖墙的需要,利用高压水射流技术设计出了一种前混式磨料水射流切割机.阐述了该切割机的设计原理和设计要求,提供了技术参数的确定办法和结构设计原则,实验表明该切割机具有独特的优点和广阔的应用前景.

  10. Study on Abrasive Water-Jet Cutting Process for Calcium Silicate Board%硅酸钙板的磨料水射流切割加工研究

    Institute of Scientific and Technical Information of China (English)

    刘绍庄

    2010-01-01

    文中详细介绍了硅酸钙板成品板磨料水射流切割加工的试验及效果,分析了其工作原理、切割压力、速度对加工质量的影响及加工消耗的材料成本,提出了磨料水射流切割加工硅酸钙板的切割参数.

  11. Manufacturing Laboratory for Next Generation Engineers

    Science.gov (United States)

    2013-12-16

    Installed Plasma CAM CNC Cutting System 6 Robotic Material Handling System (CIM system) - A Bosch Rexroth Modular Mechatronic Training system was acquired...automated CNC machines, rapid prototype systems, robotic assembly systems, metrology, and non-traditional systems such as a waterjet cutter, EDM machine...CNC machines, rapid prototype systems, robotic assembly systems, metrology, and non-traditional systems such as a waterjet cutter, EDM machine, plasma

  12. Environmental Technology Verification Coatings and Coating Equipment Program (ETV CCEP). High Transfer Efficiency Spray Equipment - Generic Verification Protocol (Revision 0)

    Science.gov (United States)

    2006-09-30

    private sector . A long-range goal of this initiative is to become a vital resource to the industry and, thus, self-sustaining through private support...High-Pressure Waterjet • CO2 Pellet/Turbine Wheel • Ultrahigh-Pressure Waterjet 5 Process Water Reuse/Recycle • Cross-Flow Microfiltration ...Diffusion Dialysis • Electrowinning • Ion Exchange • Membrane Electrolysis • Reverse Osmosis • Vacuum Evaporation 2 • Laser Figure 2. Demonstration

  13. 数控磨料水射流切割机伺服进给系统的振动爬行现象分析%Analysis on the Vibration and Crawling Phenomenon of Servo-feed System on CNC Abrasive Water-jet Cutting Machine

    Institute of Scientific and Technical Information of China (English)

    唐焱; 李连荣

    2009-01-01

    提出数控磨料水射流切割机伺服进给系统存在振动爬行现象,并对其危害、影响因素、爬行机理进行分析,通过建立物理模型和分析临界速度找到解决爬行的措施和对策,对提高系统稳定性具有实际意义.

  14. NUMERICAL SIMULATION OF ROCK BREAKING MECHANISM WITH HIGH-PRESSURE WATER JET

    Institute of Scientific and Technical Information of China (English)

    NI Hong-jian

    2004-01-01

    Based on the analysis of experimental results, the rock damage model and the damage coupling model suitable for the whole rock breaking process with water jet were established with continuous damage mechanics and micro damage mechanics, and the numerical method was developed with continuum mechanics and the FEM theory. The rock breaking mechanism with water jet was studied systematically with numerical simulation for the first time in the field of water-jet rock breaking. The numerical results agree with the experimental ones which shows that the presented method is reasonable and can reflect the reality of water-jet rock breaking. The conclusion can be applied in practice.

  15. Interaction between Brash Ice and Boat Propulsion Systems

    Science.gov (United States)

    2014-02-01

    that drive the outboard propellers are computer controlled. The motor to the propeller shaft had a 2:1 gear ratio through a belt-and- pulley ERDC TR...connected to drive gear . The same motors and gears used in the scale model outboard propulsion system were used in the waterjet intake system. The...14-1 12 Figure 11. Model’s waterjet intake system. Figure 12 shows a plan view of the motors, gears , and the Plexiglas intake. Figure 13 shows

  16. Calculation of Water Supply to Hydraulic Jet Devices

    Directory of Open Access Journals (Sweden)

    M. V. Krautsou

    2006-01-01

    Full Text Available Dependence for calculation of working fluid supply to water-air ejector is proposed. The de­pendence has been derived via analysis and processing of data being obtained by experimental research of water-jet devices.

  17. Application of Powell's analogy for the prediction of vortex-pairing sound in a low-Mach number jet based on time-resolved planar and tomographic PIV

    NARCIS (Netherlands)

    Violato, D.; Bryon, K.; Moore, P.; Scarano, F.

    2010-01-01

    This paper describes an experimental investigation by time-resolved planar and tomographic PIV on the sound production mechanism of vortex pairing of a transitional water-jet flow at Re=5000. The shear layer is characterized by axisymmetric vortex rings which undergo pairing with a varicose mode.

  18. Design of experiments in production engineering

    CERN Document Server

    2016-01-01

    This book covers design of experiments (DoE) applied in production engineering as a combination of manufacturing technology with applied management science. It presents recent research advances and applications of design experiments in production engineering and the chapters cover metal cutting tools, soft computing for modelling and optmization of machining, waterjet machining of high performance ceramics, among others.

  19. Application of Powell's analogy for the prediction of vortex-pairing sound in a low-Mach number jet based on time-resolved planar and tomographic PIV

    NARCIS (Netherlands)

    Violato, D.; Bryon, K.; Moore, P.; Scarano, F.

    2010-01-01

    This paper describes an experimental investigation by time-resolved planar and tomographic PIV on the sound production mechanism of vortex pairing of a transitional water-jet flow at Re=5000. The shear layer is characterized by axisymmetric vortex rings which undergo pairing with a varicose mode. Th

  20. Rapid prototyping of robotic platforms

    CSIR Research Space (South Africa)

    De Ronde, Willis

    2016-11-01

    Full Text Available Building a robotic platform from raw materials can take anything from a few weeks to a few years to complete, depending on the complexity and size of the platform. This paper aims to introduce a novel approach of using abrasive waterjet machining...

  1. Borehole Miner - Extendible Nozzle Development for Radioactive Waste Dislodging and Retrieval from Underground Storage Tanks

    Energy Technology Data Exchange (ETDEWEB)

    CW Enderlin; DG Alberts; JA Bamberger; M White

    1998-09-25

    This report summarizes development of borehole-miner extendible-nozzle water-jetting technology for dislodging and retrieving salt cake, sludge} and supernate to remediate underground storage tanks full of radioactive waste. The extendible-nozzle development was based on commercial borehole-miner technology.

  2. Assessment of the Applications of Water Jet Technology in Mining Sector

    Directory of Open Access Journals (Sweden)

    İzzet Karakurt

    2010-01-01

    Full Text Available Waterjet technology finding broad application potential in different areas, due to having low cutting force required and the possibility of flexible and multi-directional cutting, is used as an alternative method over the conventional cutting systems. Waterjet technology, used firstly in excavation processes of soft rocks in mining, has increased its usability with the hydraulic excavation of coal. Nowadays, it is commonly used for block cutting in quarries and processing of natural stones for the purposes of decorative production. The method has the potential use in drilling and tunneling processes too. Recently, investigations have been carried out to enhance the usability of the technology in milling processes. In this study, an assessment of some applications of waterjet technology in mining is presented. Additionally, the technology is compared with other cutting systems used in mining in terms of various aspects as well. As a result of the study, it is determined that the cutting process with waterjet technology could be efficiently used in mining sector because of the advantages such as little material losses, not requiring any additional processes after cutting, eliminating the dust, increasing the fragmentation efficiency of rock or coal, decreasing the costs resulted from wear.

  3. Processing and Mechanical Characterization of Polyurea Aerogels

    Science.gov (United States)

    2011-01-01

    filled with liquid that is later removed by supercritical drying. Once dry polyurea aerogels are difficult to form by standard methods such as machining...with a liquid solution that solidifies to form a solid gel filled with liquid that is later removed by supercritical drying. Once dry...7 Figure 2.5. Missouri University of Science and Technology Waterjet

  4. WAVESTRIDER Hullform Evaluation

    Science.gov (United States)

    1989-12-01

    physical injury such as the lower leg fractures which 1 TWIN HULL (CATAMARAN-LIKE) CRAFT SUPERCRITICAL PLANING TWO-STEPPED HULL IHYDROFOIL/PLANING PLATES...speed, the waterjet encountered cavitation 59 problems in developing sufficient thrust, and at high speed its lower efficiency demanded higher

  5. Valuable Patents for U.S. Businesses: A Catalog of DTRC Patents Available for Licensing by the Private Sector

    Science.gov (United States)

    1991-10-01

    Veazey PATENT NO: 4,553,037 DATE OF PATENT Nov. 12, 1985 TITLE: Transverse Waterjet Propulsion with Auxiliary Inlets and Impellers INVENTOR(S): John G...Lee PATENT NO: 4,398,687 DATE OF PATENT: Aug. 16, 1983 DTRC-91 /CT07 19 Valuable Patents, A Catalog TITLE: Mono-Element Combined Supercritical High

  6. Advanced Naval Vehicle Structural Loads Criteria and Structural Characteristics

    Science.gov (United States)

    1976-08-01

    cushionborne operational conditions. The recommended fatigue safety factor of 2.00 is in terms of cycles. Thus, for example, an SES hull or waterjet ...be designed to withstand the pressures and loads caused by pounding in severe sea states. Supercritical hulls which have demonstrably lower

  7. Numerical investigation of cavitation-vortex interaction in a mixed-flow water jet pump

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Renfang; Lou, Xianwu [Tsinghua University, Beijing (China); Ji, Bin [Wuhan University, Hubei (China); Zhai, Zhihong; Zhou, Jiajian [Marine Design and Research Institute of China, Shanghai (China)

    2015-09-15

    Turbulent cavitating flows in a mixed-flow waterjet pump were numerically investigated using the k-w SST turbulence model and the mass transfer cavitation model based on the Rayleigh-Plesset equation to provide a comprehensive understanding of the cavitation-vortex interaction mechanism. The predicted hydraulic performance, as well as the cavitation performance, exhibits a reasonable agreement with the experimental results. The vorticity distributions under three operation conditions were illustrated together. Based on the illustration, cavitation development enhances vorticity production and flow unsteadiness in a mixed-flow waterjet pump. Vortices are basically located at the cavity interface, particularly at the downstream interface, during cavitation. Further analyses using the relative vorticity transport equation in cavitating turbulent flows indicate that vortex dilation and baroclinic torque exhibit a steep jump as cavitation occurs. In addition, vortex stretching contributes mainly to large-scale vortex generation.

  8. LINAC 3 experiment: This experiment is used to study some scenarios of the future LEIR (low-energy ion ring) vacuum design.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Photo 1 316LN stainless steel sheet 0.7 m thick sheet metal, with water-jet cut holes; before (sheet metal) and after rolling (tube). Photo 2 316LN stainless steel tube with water-jet cut holes. Photo 3 Inner tube is fitted with NEG (non-evaporable getter) strips, creating a kind of total NEG pump. Photo 4 Inner tube is fitted with NEG (non-evaporable getter) strips, creating a kind of total NEG pump. Photo 5 Same tubes but compiled on top of each other. Photo 6 The stack of tubes is put into a vacuum chamber that will be used in the LINAC 3 experiment during summer 2002 (lead-ion beam will be used for this experiment). The holes allow all-round pumping, i.e. close to the vacuum chamber walls.

  9. Design method of water jet pump towards high cavitation performances

    Science.gov (United States)

    Cao, L. L.; Che, B. X.; Hu, L. J.; Wu, D. Z.

    2016-05-01

    As one of the crucial components for power supply, the propulsion system is of great significance to the advance speed, noise performances, stabilities and other associated critical performances of underwater vehicles. Developing towards much higher advance speed, the underwater vehicles make more critical demands on the performances of the propulsion system. Basically, the increased advance speed requires the significantly raised rotation speed of the propulsion system, which would result in the deteriorated cavitation performances and consequently limit the thrust and efficiency of the whole system. Compared with the traditional propeller, the water jet pump offers more favourite cavitation, propulsion efficiency and other associated performances. The present research focuses on the cavitation performances of the waterjet pump blade profile in expectation of enlarging its advantages in high-speed vehicle propulsion. Based on the specifications of a certain underwater vehicle, the design method of the waterjet blade with high cavitation performances was investigated in terms of numerical simulation.

  10. Identification of Upper and Lower Level Yield Strength in Materials

    Science.gov (United States)

    Valíček, Jan; Harničárová, Marta; Kopal, Ivan; Palková, Zuzana; Kušnerová, Milena; Panda, Anton; Šepelák, Vladimír

    2017-01-01

    This work evaluates the possibility of identifying mechanical parameters, especially upper and lower yield points, by the analytical processing of specific elements of the topography of surfaces generated with abrasive waterjet technology. We developed a new system of equations, which are connected with each other in such a way that the result of a calculation is a comprehensive mathematical–physical model, which describes numerically as well as graphically the deformation process of material cutting using an abrasive waterjet. The results of our model have been successfully checked against those obtained by means of a tensile test. The main prospect for future applications of the method presented in this article concerns the identification of mechanical parameters associated with the prediction of material behavior. The findings of this study can contribute to a more detailed understanding of the relationships: material properties—tool properties—deformation properties. PMID:28832526

  11. Ultra-high pressure water jet: Baseline report; Greenbook (chapter)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The technologies being tested for concrete decontamination are targeted for alpha contamination. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  12. Powering Performance of a High-Speed Shallow-Water Craft

    Institute of Scientific and Technical Information of China (English)

    HEShu-long; XINGSheng-de; HEChun-rong

    2004-01-01

    Hull form of a high-speed shallow-water craft used in fresh water is presented in this paper.Model tests for this hull lines are conducted at different water depth in towing tank, and the effect of shallow water on craft performance is investigated.Test resalts show that powering performance of this craft is superior to other representativeplanningboat, no matter in deep or shallow water.Concept of double-inlet water-jet system is designed with one inlet in side and the other in bottom.This craft,combined with the double-inlet water-jet system, can run in deep water with high speed and safely run in shallow water.The critical water depth can almost be the same as the draft of this craft.

  13. Investigation of sandwich material surface created by abrasive water jet (AWJ via vibration emission

    Directory of Open Access Journals (Sweden)

    P. Hreha

    2014-01-01

    Full Text Available The paper presents research a of abrasive waterjet cutting of heterogeneous “sandwich“ material with different Young modulus of elasticity of the cutted surface geometry by means of vibration emission. In order to confirm hypothetical assumptions about direct relation between vibration emission and surface quality an experiment in heterogeneous material consisting of stainless steel (DIN 1.4006 / AISI 410 and alloy AlCuMg2 has been provided.

  14. A nonlinear programming method for system design with results that have been implemented

    Science.gov (United States)

    Hauser, F.

    1984-01-01

    A general nonlinear programming algorithm (NICO) is discussed. An academic optimization example is given. The NICO multi-input, multi-output control system design is discussed. NICO applications relative to launch vehicle autopilot design, space shuttle static balance, transient response criteria in the design of a reentry vehicle control system, and waterjet propulsion and lift system components sized to a large surface effect ship are noted.

  15. Residual Stress Improved by Water Jet Peening for A Quenched Gear

    Institute of Scientific and Technical Information of China (English)

    Dong-Ying Ju; H. Tsuda; Vincent Ji; T. Uchiyama; R. Oba

    2004-01-01

    In this paper, a running cost is cheap from the thing used for harmless peening treatment to the environment,health which an influence is rare in toward processing material like heat being only water fundamentally, and economical,and the characteristics is hard to get are given. There is some research about the residual stress improvement by water-jet peening during the high-speed water. In this study, a big bubble cloud ceremony water-jet peening which dissolves the problem of the form of the applicable thing by exposing the whole of the applicable thing in the big bubble cloud as the way of dealing with peening efficiently in a short time is proposed by this research. Moreover, the uniform compression residual stress is added around the surface of the processing side, and connected with the remarkable improvement of the fatigue strength of the part. Furthermore, and safety processing is very possible, and it thinks about the thing which has possible high practical use, and writers to get rid of the problems of the way of processing it with peening until now. Water-jet peening was given by this research during high-speed water with big bubble cloud-type water toward tooth gear manufactured by SCr420H3V2 to open the effect of water-jet peening during the high-speed water. A change was measured at the time as the sutra of the residual stress on the surface of the test settlement by the X-ray method, and the validity of this law was verified.

  16. Water jet: a promising method for cutting optical glass

    Science.gov (United States)

    Salinas-Luna, Javier; Machorro, Roberto; Camacho, Javier; Luna, Esteban; Nunez, Juan

    2006-05-01

    We present an alternative method for cutting optical glass. It works with a high-pressure fluid, carring abrasive powder. This technique offers some advantages over conventional methods that use diamond abrasive covered wires or disks. We make a critical comparison between those two techniques, characterizing cuts with interferometric, polarimetric, and Ronchi testing. The main feature of the water-jet technique is that it allows surface of any shape, already polished, to be cut safely.

  17. Field performance of the waste retrieval end effectors in the Oak Ridge gunite tanks

    Energy Technology Data Exchange (ETDEWEB)

    Mullen, O.D.

    1997-09-01

    Waterjet-based tank waste retrieval end effectors have been developed by Retrieval Process Development and Enhancements through several generations of test articles targeted at deployment in Hanford underground storage tanks with a large robotic arm. The basic technology has demonstrated effectiveness for retrieval of simulants bounding a wide range of waste properties and compatibility with foreseen deployment systems. The Oak Ridge National Laboratory (ORNL) selected the waterjet scarifying end effector, the jet pump conveyance system, and the Modified Light Duty Utility Arm and Houdini Remotely Operated Vehicle deployment and manipulator systems for evaluation in the Gunite and Associated Tanks Treatability Study (GAAT-TS). The Retrieval Process Development and Enhancements (RPD&E) team was tasked with developing a version of the retrieval end effector tailored to the Oak Ridge tanks, waste, and deployment platforms. The conceptual design was done by the University of Missouri-Rolla in FY 1995-96. The university researchers conducted separate effects tests of the component concepts, scaled the basic design features, and constructed a full-scale test article incorporating their findings in early FY 1996. The test article was extensively evaluated in the Hanford Hydraulic Testbed and the design features were further refined. Detail design of the prototype item was started at Waterjet Technology, Inc. before the development testing was finished, and two of the three main subassemblies were substantially complete before final design of the waterjet manifold was determined from the Hanford hydraulic testbed (HTB) testing. The manifold on the first prototype was optimized for sludge retrieval; assembled with that manifold, the end effector is termed the Sludge Retrieval End Effector (SREE).

  18. Air Quality Management Using Pollution Prevention: A Joint Service Approach

    Science.gov (United States)

    1998-03-01

    Supercritical Carbon Dioxide •= May be suitable for degreasing processes •= May not be the best option for substitution •= Extensive redesign...system uses a manlift with a waterjet nozzle and 32 recovery shroud mounted at the end of the boom in place of a personnel basket. The system does...be higher because of the decreased time needed for curing. Background: Supercritical CO2 Spraying Supercritical CO2 Spraying is a paint spraying

  19. Reducing the contamination of beef carcasses by specified risk materials during slaughter

    Directory of Open Access Journals (Sweden)

    Elena Bozzetta

    2013-04-01

    Full Text Available According to the European Community Regulation 1139/2003, a sampling plan based on an appropriate tests to detect the presence of central nervous system (CNS tissue on the surface of the head muscles had to be implemented in each member state starting from 2003. In previous studies, we showed a medium CNS contamination in head meat from Italian slaughterhouses of 14,7%. Recently, German authors referred about alarming rates (82% of CNS contamination in para-vertebral muscles after routine carcass splitting and spinal cord removal practices. In that context, the authors intended to assess the percentage of CNS contamination in muscles close to the vertebral column obtained by applying three different removal practices of specific risk material (SRM. Two alternative techniques, by sucking out and by water-jet, were compared to the traditional one; in both situations the removal of spinal cord occurred before the carcass splitting. The percentage of contamination resulted 62% applying the traditional technique, 60% with the sucking out system and 36% using the water-jet. The results show that water-jet ensures the most significant reduction of SRM contamination in para-vertebral meat as it guarantees a rapid and complete extraction of the spinal cord.

  20. HEMISPHERIC CENTER FOR ENVIRONMENTAL TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian

    1999-01-31

    FIU-HCET participated in an ICT meeting at Mound during the second week of December and presented a brief videotape of the testing of the Robotic Climber technology. During this meeting, FIU-HCET proposed the TechXtract technology for possible testing at Mound and agreed to develop a five-page proposal for review by team members. FIU-HCET provided assistance to Bartlett Inc. and General Lasertronics Corporation in developing a proposal for a Program Opportunity Notice (PON). The proposal was submitted by these companies on January 5, 1999. The search for new equipment dismantlement technologies is continuing. The following vendors have responded to requests for demonstration: LUMONICS, Laser Solutions technology; CRYO-BEAM, Cryogenic cutting technology; Waterjet Technology Association, Waterjet Cutting technology; and DIAJET, Waterjet Cutting technology. Based on the tasks done in FY98, FIU-HCET is working closely with Numatec Hanford Corporation (NHC) and Pacific Northwest National Laboratory (PNNL) to revise the plan and scope of work of the pipeline plugging project in FY99, which involves activities of lab-scale flow loop experiments and a large-scale demonstration test bed.

  1. Bauxite washing for the removal of clay

    Institute of Scientific and Technical Information of China (English)

    Ishaq Ahmad; Ernst-Ulrich Hartge; Joachim Werther; and Reiner Wischnewski

    2014-01-01

    Clay impurities associated with bauxite negatively affect the Bayer process for alumina production. These impurities should be removed as far as possible by a beneficiation technique before the ore is used as feed for the Bayer process. In this current investigation, bauxite washing was conducted in the laboratory. Bauxite washing is a physical process that causes the disintegration and deagglomeration of the clay matrix, and bauxite is liberated from the clay (mainly rich in silica). Subsequently, separation occurs with the assistance of wet screening at a predetermined cut size. Three techniques were investigated in the laboratory: drum washing, water-jet washing, and ultrasonic washing. Various operating parameters were investigated for drum washing and water-jet washing, including materials retention time, drum rotation speed, solid concentration, water-jet spray duration, pressure, and height. We concluded that the retention time of bauxite inside the drum at a solid concentration of 55wt% and a drum rotation speed of 31 r/min is the dominant parameter for the removal of clay from the bauxite surface.

  2. Fractal Characteristic of Rock Cutting Load Time Series

    Directory of Open Access Journals (Sweden)

    Hongxiang Jiang

    2014-01-01

    Full Text Available A test-bed was developed to perform the rock cutting experiments under different cutting conditions. The fractal theory was adopted to investigate the fractal characteristic of cutting load time series and fragment size distribution in rock cutting. The box-counting dimension for the cutting load time series was consistent with the fractal dimension of the corresponding fragment size distribution, which indicated that there were inherent relations between the rock fragmentation and the cutting load. Furthermore, the box-counting dimension was used to describe the fractal characteristic of cutting load time series under different conditions. The results show that the rock compressive strength, cutting depth, cutting angle, and assisted water-jet types all have no significant effect on the fractal characteristic of cutting load. The box-counting dimension can be an evaluation index to assess the extent of rock crushing or cutting. Rock fracture mechanism would not be changed due to water-jet in front of or behind the cutter, but it would be changed when the water-jet was in cutter.

  3. Bauxite washing for the removal of clay

    Science.gov (United States)

    Ahmad, Ishaq; Hartge, Ernst-Ulrich; Werther, Joachim; Wischnewski, Reiner

    2014-11-01

    Clay impurities associated with bauxite negatively affect the Bayer process for alumina production. These impurities should be removed as far as possible by a beneficiation technique before the ore is used as feed for the Bayer process. In this current investigation, bauxite washing was conducted in the laboratory. Bauxite washing is a physical process that causes the disintegration and deagglomeration of the clay matrix, and bauxite is liberated from the clay (mainly rich in silica). Subsequently, separation occurs with the assistance of wet screening at a predetermined cut size. Three techniques were investigated in the laboratory: drum washing, water-jet washing, and ultrasonic washing. Various operating parameters were investigated for drum washing and water-jet washing, including materials retention time, drum rotation speed, solid concentration, water-jet spray duration, pressure, and height. We concluded that the retention time of bauxite inside the drum at a solid concentration of 55wt% and a drum rotation speed of 31 r/min is the dominant parameter for the removal of clay from the bauxite surface.

  4. Ossification of the frontal sinus in juvenile minipigs following water jet application.

    Science.gov (United States)

    Lenz, Jan-Hendrik; Henkel, Kai-Olaf; Schmidt, Wolfgang; Fulda, Gerhard; Hingst, Volker; Gundlach, Karsten K H

    2006-03-01

    Obliteration of the frontal sinus is a generally accepted management for patients with severe craniofacial trauma in whom the sinus cannot be repaired or adequately drained. Effective obliteration requires complete removal of mucosa, sufficient filling of the sinus cavity as well as effective occlusion of the nasofrontal duct. The use of various filling materials for sinus obliteration has been described and include autologous fat, bone, muscle and lyophilized cartilage. In order to appreciate the advantages of the water-jet scalpel an animal study in 10 juvenile (4 months old) and 10 adult (18 months) minipigs was performed. In 5 juvenile and 5 adult animals the frontal sinus mucosa was removed using the water jet, while in the others bone curettes were used. No occlusion of the frontonasal duct was carried out and no filling material was implanted. All animals were followed-up for 40 days. After sacrifice, radiological, histological and computerized histomorphometrical examinations were carried out. Removal of the mucosa from the sinus was simplified when using the water jet. Previous studies have shown that the selected tissue structures were less traumatized when compared with conventional surgical techniques. In young animals (only) and exclusively following the use of a water-jet scalpel osseous occlusion of the frontal sinus was found at follow-up. Histomorphometric findings revealed a significant increase of bone formation in the frontal sinus area of these animals. Based on these experimental results in a small series of juvenile minipigs the water-jet technique is a faster and less traumatic technique (less blood loss) for osteoplastic surgery of the frontal sinus. Further long-term studies are needed to evaluate the possibilities for applying this technique in post-traumatic craniofacial surgery in man.

  5. Liver resection using a water jet.

    Science.gov (United States)

    Une, Y; Uchino, J; Horie, T; Sato, Y; Ogasawara, K; Kakita, A; Sano, F

    1989-01-01

    The water-jet method has been used during hepatic resection. The instrument cuts the hepatic tissue with the high pressure of the fine water flow, while the exposed elastic intrahepatic vessels are spared injury. A comparative study on the water-jet method with the previously employed conventional methods was undertaken. Hepatic resections were performed on 35 patients using the water-jet method. Cirrhosis of the liver was associated with 10 of the 24 patients with hepatocellular carcinoma. An ordinary saline solution was used as the jet, which was projected at a pressure of between 12 kg/cm2 and 20 kg/cm2 through a 0.15/mm-diameter nozzle. A higher jet pressure was needed to cut the fibrotic hepatic parenchyma. In the case of normal liver, the intrahepatic vessels of more than 0.2 mm were well preserved. In most of the cases, the loss of blood when cutting the hepatic parenchyma can be easily reduced with a jet pressure of 15-16 kg/cm2, thus preserving the fine vessels more than 0.2 mm in diameter without injury. When the same pressure was applied in the cutting of a cirrhotic liver, it took much longer time compared to that of a non-cirrhotic normal liver parenchyma. The cut surface was smooth compared to that after using CUSA, although its disadvantages lie in the formation of air bubbles, which obscure the operative field. The controlled projection of a jet of water under optimal pressure may ensure a safe hepatic resection of both normal and cirrhotic livers. Furthermore, because of its uncomplicated form, a wide range of applications can be expected, while the lower cost will also expedite its large-scale use for economic reasons.

  6. Detecting the Ma‘agan Mikhael B shipwreck

    DEFF Research Database (Denmark)

    Cvikel, Deborah; Grøn, Ole; Boldreel, Lars Ole

    2017-01-01

    A shipwreck, designated as Ma‘agan Mikhael B, was discovered in 2005 by divers about 70 m from the shoreline and at a depth of 1 m, embedded in sandy seafloor sediments. Soon after, the shipwreck was lost in the sand. In May 2015, it was located in a survey with a chirp sub-bottom profiler, and a......, and a water-jetting survey in August 2015 confirmed its position. This paper discusses the detection of the Ma‘agan Mikhael B shipwreck using a chirp sub-bottom profiler....

  7. Evaluating the cost effectiveness of environmental projects: Case studies in aerospace and defense

    Science.gov (United States)

    Shunk, James F.

    1995-01-01

    Using the replacement technology of high pressure waterjet decoating systems as an example, a simple methodology is presented for developing a cost effectiveness model. The model uses a four-step process to formulate an economic justification designed for presentation to decision makers as an assessment of the value of the replacement technology over conventional methods. Three case studies from major U.S. and international airlines are used to illustrate the methodology and resulting model. Tax and depreciation impacts are also presented as potential additions to the model.

  8. Machining of composite materials. I - Traditional methods. II - Non-traditional methods

    Science.gov (United States)

    Abrate, S.; Walton, D. A.

    Traditional and nontraditional methods for machining organic-matrix and metal-matrix composites are reviewed. Such traditional procedures as drilling, cutting, sawing, routing, and grinding are discussed together with the damage introduced into composites by these manipulations. Particular attention is given to new, nontraditional methods, including laser, water-jet, electrodischarge, electrochemical spark, and ultrasonic machining methods showing that, these methods often speed up cutting and improve the surface quality. Moreover, it is sometimes possible to use new methods in cases where traditional methods are ineffective.

  9. Cryogenic optical performance of a lightweighted mirror assembly for future space astronomical telescopes: correlating optical test results and thermal optical model

    Science.gov (United States)

    Eng, Ron; Arnold, William R.; Baker, Markus A.; Bevan, Ryan M.; Burdick, Gregory; Effinger, Michael R.; Gaddy, Darrell E.; Goode, Brian K.; Hanson, Craig; Hogue, William D.; Kegley, Jeffrey R.; Kirk, Charlie; Maffett, Steven P.; Matthews, Gary W.; Siler, Richard D.; Smith, W. Scott; Stahl, H. Philip; Tucker, John M.; Wright, Ernest R.

    2013-09-01

    A 43cm diameter stacked core mirror demonstrator was interferometrically tested at room temperature down to 250 degrees Kelvin for thermal deformation. The 2.5m radius of curvature spherical mirror assembly was constructed by low temperature fusing three abrasive waterjet core sections between two CNC pocket milled face sheets. The 93% lightweighted Corning ULE® mirror assembly represents the current state of the art for future UV, optical, near IR space telescopes. During the multiple thermal test cycles, test results of interferometric test, thermal IR images of the front face were recorded in order to validate thermal optical model.

  10. Multi-objective genetic algorithm for the optimization of road surface cleaning process

    Institute of Scientific and Technical Information of China (English)

    CHEN Jie; GAO Dao-ming

    2006-01-01

    The parameters affecting road surface cleaning using waterjets were researched and a fuzzy neural network method of calculating cleaning rate was provided. A genetic algorithm was used to configure the cleaning parameters of pressure, standoff distance, traverse rate and angle of nozzles for the optimization of the cleaning effectiveness, efficiency, energy and water consumption, and a multi-objective optimization model was established. After calculation, the optimized results and the trend of variation of cleaning effectiveness, efficiency, energy and water consumption in different weighting factors were analyzed.

  11. Hanford Tanks Initiative alternate retrieval system demonstrations - final report of testing performed by Grey Pilgrim LLC

    Energy Technology Data Exchange (ETDEWEB)

    Berglin, E.J.

    1997-07-24

    A waste retrieval system has been defined to provide a safe and cost-effective solution to the Hanford Tanks Initiative. This system consists of the EMMA robotic manipulator (by GreyPilgrim LLC) and the lightweight Scarifier (by Waterjet Technology, Inc.) powered by a 36-kpsi Jet-Edge diesel powered high pressure pumping system. For demonstration and testing purposes, an air conveyance system was utilized to remove the waste from the simulated tank floor. The EMMA long reach manipulator utilized for this demonstration was 33 feet long. It consisted of 4 hydraulically controlled stages of varying lengths and coupling configurations. T

  12. HYDRAULIC ELEVATOR INSTALLATION ESTIMATION FOR THE WATER SOURCE WELL SAND-PACK CLEANING UP

    Directory of Open Access Journals (Sweden)

    V. V. Ivashechkin

    2016-01-01

    Full Text Available The article offers design of a hydraulic elevator installation for cleaning up water-source wells of sand packs. It considerers the installation hydraulic circuit according to which the normal pump feeds the high-level tank water into the borehole through two parallel water lines. The water-jet line with washing nozzle for destroying the sand-pack and the supply pipe-line coupled with the operational nozzle of the hydraulic elevator containing the inlet and the supply pipelines for respectively intaking the hydromixture and removing it from the well. The paper adduces equations for fluid motion in the supply and the water-jet pipelines and offers expressions for evaluating the required heads in them. For determining water flow in the supply and the water-jet pipe lines the author proposes to employ graphical approach allowing finding the regime point in Q–H chart by means of building characteristics of the pump and the pipe-lines. For calculating the useful vertical head, supply and dimensions of the hydraulic elevator the article employs the equation of motion quantity with consistency admission of the motion quantity before and after mixing the flows in the hydraulic elevator. The suggested correlations for evaluating the hydraulic elevator efficiency determine the sand pack removal duration as function of its sizes and the ejected fluid flow rate. A hydraulic-elevator installation parameters estimation example illustrates removing a sand pack from a water-source borehole of 41 m deep and 150 mm diameter bored in the village of Uzla of Myadelsk region, of Minsk oblast. The working efficiency of a manufactured and laboratory tested engineering prototype of the hydraulic elevator installation was acknowledged in actual tests at the indicated borehole site. With application of graphical approach, the suggested for the hydraulic elevator installation parameters calculation procedure allows selecting, with given depth and the borehole diameter

  13. Effects of water blowers on service life of combustion chamber heating surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Habryka, A. (Zaklad Techniki Cieplnej i Gospodarki Energetycznej (Poland))

    1990-07-01

    Discusses control of fouling in steam generators of coal-fired power plants and the performance of water jet equipment. Heating surfaces of combustion chambers were monitored by optical probes, industrial television cameras, photo- and film cameras. Continuous observation was accompanied by temperature measurements with thermocouples. Negative effects of water jet application and experience gained in Poland, Estonia and in the FRG concerning periods of cleaning cycles are considered. Improved heating surface cleaning procedures and application of water-jet cleaners of the type used in the Thierbach and Jaenschwalde power plants (FRG) are recommended. 8 refs.

  14. Cryogenic Optical Performance of a Lightweighted Mirror Assembly for Future Space Astronomical Telescopes: Correlating Optical Test Results and Thermal Optical Model

    Science.gov (United States)

    Eng, Ron; Arnold, William R.; Baker, Marcus A.; Bevan, Ryan M.; Burdick, Gregory; Effinger, Michael R.; Gaddy, Darrell E.; Goode, Brian K.; Hanson, Craig; Hogue, William D.; Kegley, Jeffrey R.; Kirk, Charlie; Maffett, Steven P.; Matthews, Gary W.; Siler, Richard D.; Smith, W. Scott; Stahl, H. Philip; Tucker, John M.; Wright, Ernest R.

    2013-01-01

    A 43cm diameter stacked core mirror demonstrator was interferometrically tested at room temperature down to 250 degrees Kelvin for thermal deformation. The 2.5m radius of curvature spherical mirror assembly was constructed by low temperature fusing three abrasive waterjet core sections between two CNC pocket milled face sheets. The 93% lightweighted Corning ULE® mirror assembly represents the current state of the art for future UV, optical, near IR space telescopes. During the multiple thermal test cycles, test results of interferometric test, thermal IR images of the front face were recorded in order to validate thermal optical model.

  15. Cryogenic Optical Performance of a Light-weight Mirror Assembly for Future Space Astronomical Telescopes: Optical Test Results and Thermal Optical Model

    Science.gov (United States)

    Eng, Ron; Arnold, William; Baker, Markus A.; Bevan, Ryan M.; Carpenter, James R.; Effinger, Michael R.; Gaddy, Darrell E.; Goode, Brian K.; Kegley, Jeffrey R.; Hogue, William D.; Siler, Richard D.; Smith, W. Scott; Stahl. H. Philip; Tucker, John M.; Wright, Ernest R.; Kirk, Charles S.; Hanson, Craig; Burdick, Gregory; Maffett, Steven

    2013-01-01

    A 40 cm diameter mirror assembly was interferometrically tested at room temperature down to 250 degrees Kelvin for thermal deformation. The 2.5 m radius of curvature spherical mirror assembly was constructed by low temperature fusing three abrasive waterjet core sections between two face sheets. The 93% lightweighted Corning ULE mirror assembly represents the current state of the art for future UV, optical, near IR space telescopes. During the multiple thermal test cycles, test results of interferometric test, thermal IR images of the front face were recorded in order to validate thermal optical model.

  16. Index to the Shock and Vibration Bulletins

    Science.gov (United States)

    1968-02-01

    facilities Reynold’s number graph, 26-2-172 supercritical in study of flow of incompressi- ble fluids, 26-2-147 vortex discharge at, 26-2-147, 180...used in shipboard shock tests, 29-1-12 Velocity generators, waterjet actuators, for sled tests, 35-6-47 Vermiculite, shock mitigating character...towers and other struc- tures, 34-2-279 at supercritical Reynolds number, 26-2-147,180 Vulnerability of aircraft to blast, 28-1-56 to nuclear

  17. Plasma-Spray Metal Coating On Foam

    Science.gov (United States)

    Cranston, J.

    1994-01-01

    Molds, forms, and other substrates made of foams coated with metals by plasma spraying. Foam might be ceramic, carbon, metallic, organic, or inorganic. After coat applied by plasma spraying, foam left intact or removed by acid leaching, conventional machining, water-jet cutting, or another suitable technique. Cores or vessels made of various foam materials plasma-coated with metals according to method useful as thermally insulating containers for foods, liquids, or gases, or as mandrels for making composite-material (matrix/fiber) parts, or making thermally insulating firewalls in automobiles.

  18. Investigation of cutting-induced damage in CMC bend bars

    Directory of Open Access Journals (Sweden)

    Neubrand A.

    2015-01-01

    Full Text Available Ceramic matrix composites (“CMC” with a strong fibre-matrix interface can be made damage-tolerant by introducing a highly porous matrix. Such composites typically have only a low interlaminar shear strength, which can potentially promote damage when preparing specimens or components by cutting. In order to investigate the damage induced by different cutting methods, waterjet cutting with and without abrasives, laser-cutting, wire eroding and cutoff grinding were used to cut plates of two different CMCs with a matrix porosity up to 35 vol.-%. For each combination of cutting method and composite, the flexural and interlaminar shear strength of the resulting specimens was determined. Additionally, the integrity of the regions near the cut surfaces was investigated by high-resolution x-ray computer tomography. It could be shown that the geometrical quality of the cut is strongly affected by the cutting method employed. Laser cut and waterjet cut specimens showed damage and delaminations near the cut surface leading to a reduced interlaminar shear strength of short bend bars in extreme cases.

  19. Ultra-high pressure water jet: Baseline report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The safety and health evaluation during the testing demonstration focused on two main areas of exposure. These were dust and noise. The dust exposure was found to be minimal, which would be expected due to the wet environment inherent in the technology, but noise exposure was at a significant level. Further testing for noise is recommended because of the outdoor environment where the testing demonstration took place. In addition, other areas of concern found were arm-hand vibration, ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, fall hazards, slipping hazards, hazards associated with the high pressure water, and hazards associated with air pressure systems.

  20. Engineering development of waste retrieval end effectors for the Oak Ridge gunite waste tanks

    Energy Technology Data Exchange (ETDEWEB)

    Mullen, O.D.

    1997-05-01

    The Gunite and Associated Tanks Treatability Study at Oak Ridge National Laboratory selected the waterjet scarifying end effector, the jet pump conveyance system, and the Modified Light Duty Utility Arm and Houdini Remotely Operated Vehicle deployment and manipulator systems for evaluation. The waterjet-based retrieval end effector had been developed through several generations of test articles targeted at deployment in Hanford underground storage tanks with a large robotic arm. The basic technology had demonstrated effectiveness at retrieval of simulants bounding the foreseen range of waste properties and indicated compatibility with the planned deployment systems. The Retrieval Process Development and Enhancements team was tasked with developing a version of the retrieval end effector tailored to the Oak Ridge tanks, waste and deployment platforms. The finished prototype was delivered to PNNL and subjected to a brief round of characterization and performance testing at the Hydraulic Testbed prior to shipment to Oak Ridge. It has undergone extensive operational testing in the Oak Ridge National Laboratory Tanks Technology Cold Test Facility and performed well, as expected. A second unit has been delivered outfitted with the high pressure manifold.

  1. A coupled three-dimensional hydrodynamic model for predicting hypolimnetic oxygenation and epilimnetic mixing in a shallow eutrophic reservoir

    Science.gov (United States)

    Chen, Shengyang; Lei, Chengwang; Carey, Cayelan C.; Gantzer, Paul A.; Little, John C.

    2017-01-01

    Artificial mixing and hypolimnetic oxygenation are two common methods for improving water quality in reservoirs. To examine the effects of their operation on the thermal structure of the water column, we used a three-dimensional hydrodynamic model coupled with a newly developed water-jet model and an existing linear bubble-plume model in conjunction with whole-reservoir in situ mixing experiments in a drinking-water reservoir. This reservoir has a side-stream supersaturation (SSS) hypolimnetic oxygenation system and a bubble-plume epilimnetic mixing (EM) system installed to reduce hypolimnetic hypoxia and algal blooms. The results show that the SSS successfully adds dissolved oxygen to the hypolimnion without destratifying the reservoir, whereas the EM, located at the lower metalimnetic boundary, deepens this boundary and partially mixes the metalimnion and epilimnion. The newly developed water-jet model coupled with the hydrodynamic model can successfully predict the variation of the thermal structure in the reservoir. The extent to which the SSS and EM systems affect the thermal structure of the reservoir is also quantified by further application of the coupled hydrodynamic model.

  2. Preparation of chitosan nanofibers from completely deacetylated chitosan powder by a downsizing process.

    Science.gov (United States)

    Aklog, Yihun Fantahun; Dutta, Ajoy Kumar; Izawa, Hironori; Morimoto, Minoru; Saimoto, Hiroyuki; Ifuku, Shinsuke

    2015-01-01

    Chitosan nanofibers were easily prepared from fully deacetylated chitosan dry powder using a high-pressure waterjet system. From SEM observation, after 10 cycles of treatment, most of the chitosan had been reduced to homogeneous nanofibers measuring tens of nanometers. On the other hand, further mechanical treatment did not show a significant change. Relative crystallinity of chitosan nanofibers gradually decreased as the number of passes increased since high-pressure waterjet treatment damaged the crystalline region of chitosan nanofibers. The transmittance of the chitosan nanofiber slurry increased steeply, as the number of passes increased, indicating that the chitosan fibers were disintegrated effectively. Viscosity of chitosan nanofiber slurry also showed that the chitosan disintegrated well into nanofibers up to 10 passes. Above 10 passes, disintegration efficiency was saturated. The molecular weights of the nanofibers steeply decreased due to the depolymerization of chitosan by mechanical disintegration. The Young's modulus and tensile strength of chitosan nanofiber sheets were improved as the number of treatments increased, but further treatments deteriorated the tensile strength.

  3. Cohesive Laws for Analyzing Through-Crack Propagation in Cross Ply Laminates

    Science.gov (United States)

    Bergan, Andrew C.; Davila, Carlos G.

    2015-01-01

    The laminate cohesive approach (LCA) is a methodology for the experimental characterization of cohesive through-the-thickness damage propagation in fiber-reinforced polymer matrix composites. LCA has several advantages over other existing approaches for cohesive law characterization, including: visual measurements of crack length are not required, structural effects are accounted for, and LCA can be applied when the specimen is too small to achieve steady-state fracture. In this work, the applicability of this method is investigated for two material systems: IM7/8552, a conventional prepreg, and AS4/VRM34, a non-crimp fabric cured using an out-of-autoclave process. The compact tension specimen configuration is used to propagate stable Mode I damage. Trilinear cohesive laws are characterized using the fracture toughness and the notch tip opening displacement. Test results are compared for the IM7/8552 specimens with notches machined by waterjet and by wire slurry saw. It is shown that the test results are nearly identical for both notch tip preparations methods, indicating that significant specimen preparation time and cost savings can be realized by using the waterjet to notch the specimen instead of the wire slurry saw. The accuracy of the cohesive laws characterized herein are assessed by reproducing the structural response of the test specimens using computational methods. The applicability of the characterization procedure for inferring lamina fracture toughness is also discussed.

  4. Predictors for identification of stigmata of recent hemorrhage on colonic diverticula in lower gastrointestinal bleeding.

    Science.gov (United States)

    Niikura, Ryota; Nagata, Naoyoshi; Aoki, Tomonori; Shimbo, Takuro; Tanaka, Shohei; Sekine, Katsunori; Kishida, Yoshihiro; Watanabe, Kazuhiro; Sakurai, Toshiyuki; Yokoi, Chizu; Yanase, Mikio; Akiyama, Junichi; Mizokami, Masashi; Uemura, Naomi

    2015-03-01

    The aim of this study was to identify predictors for the identification of stigmata of recent hemorrhage (SRH) on colonic diverticula. Several factors influence the identification of SRH in the diagnosis of colonic diverticular bleeding. A total of 396 patients hospitalized for lower gastrointestinal bleeding were analyzed. Comorbidities, medications, timing of colonoscopy [48 h], preparation, expert colonoscopist, use of a cap, use of a water-jet scope, total colonoscopy, and procedure time (over 60 min) were assessed. A multivariable logistic regression model was used to estimate odds ratio (OR) and 95% confidence interval (CI). Two hundred fifteen patients were diagnosed with colonic diverticular bleeding and 37 (17%) were identified with SRH. Urgent colonoscopy (OR, 8.4; 95% CI, 2.3-30; P48 hours groups (1.0%, P<0.01), showing a tendency to decrease with time (P<0.01 for trend). Factors of urgent colonoscopy, expert colonoscopist, use of a cap, and use of water-jet scope are useful for identifying SRH diverticula.

  5. Innovative technology summary report: Confined sluicing end effector

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    A Confined Sluicing End-Effector (CSEE) was field tested during the summer of 1997 in Tank W-3, one of the Gunite and Associated Tanks (GAAT) at the Oak Ridge Reservation (ORR). It should be noted that the specific device used at the Oak Ridge Reservation demonstration was the Sludge Retrieval End-Effector (SREE), although in common usage it is referred to as the CSEE. Deployed by the Modified Light-Duty Utility Arm (MLDUA) and the Houdini remotely operated vehicle (ROV), the CSEE was used to mobilize and retrieve waste from the tank. After removing the waste, the CSEE was used to scarify the gunite walls of Tank W-3, removing approximately 0.1 in of material. The CSEE uses three rotating water-jets to direct a short-range pressurized jet of water to effectively mobilize the waste. Simultaneously, the water and dislodged tank waste, or scarified materials, are aspirated using a water-jet pump-driven conveyance system. The material is then pumped outside of the tank, where it can be stored for treatment. The technology, its performance, uses, cost, and regulatory issues are discussed.

  6. Experimental study on variations in Charpy impact energies of low carbon steel, depending on welding and specimen cutting method

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaorui; Kang, Hansaem; Lee, Young Seog [Chung-Ang University, Seoul (Korea, Republic of)

    2016-05-15

    This paper presents an experimental study that examines variations of Charpy impact energy of a welded steel plate, depending upon the welding method and the method for obtaining the Charpy specimens. Flux cored arc welding (FCAW) and Gas tungsten arc welding (GTAW) were employed to weld an SA516 Gr. 70 steel plate. The methods of wire cutting and water-jet cutting were adopted to take samples from the welded plate. The samples were machined according to the recommendations of ASTM SEC. II SA370, in order to fit the specimen dimension that the Charpy impact test requires. An X-ray diffraction (XRD) method was used to measure the as-weld residual stress and its redistribution after the samples were cut. The Charpy impact energy of specimens was considerably dependent on the cutting methods and locations in the welded plate where the specimens were taken. The specimens that were cut by water jet followed by FCAW have the greatest resistance-to-fracture (Charpy impact energy). Regardless of which welding method was used, redistributed transverse residual stress becomes compressive when the specimens are prepared using water-jet cutting. Meanwhile, redistributed transverse residual stress becomes tensile when the specimens are prepared using wire cutting.

  7. Retrieval process development and enhancements: Hydraulic test bed integrated testing. Fiscal year 1995 technology development summary report

    Energy Technology Data Exchange (ETDEWEB)

    Hatchell, B.K.; Smalley, J.T.; Tucker, J.C.

    1996-02-01

    The Retrieval Process Development and Enhancements Program is sponsored by the U.S. Department of Energy (DOE) Office of Science and Technology to investigate waste dislodging and conveyance processes suitable for the retrieval of high-level radioactive waste. This program, represented by industry, national laboratories, and academia, is testing the performance of a technology of high-pressure waterjet dislodging and pneumatic conveyance integrated as a scarifier as a means of retrieval of waste inside waste storage tanks. Waste stimulants have been designed to challenge this retrieval process, and this technology has been shown to mobilize and convey the waste stimulants, at target retrieval rates while operating within the space envelope and the dynamic loading constraints of postulated deployment systems. The approach has been demonstrated to be versatile in dislodging and conveying a broad range of waste forms, from hard wastes to soft sludge wastes, through the use of simple and reliable in-tank components.

  8. Novel Repair Concept for Composite Materials by Repetitive Geometrical Interlock Elements

    Directory of Open Access Journals (Sweden)

    David Zaremba

    2011-12-01

    Full Text Available Material adapted repair technologies for fiber-reinforced polymers with thermosetting matrix systems are currently characterized by requiring major efforts for repair preparation and accomplishment in all industrial areas of application. In order to allow for a uniform distribution of material and geometrical parameters over the repair zone, a novel composite interlock repair concept is introduced, which is based on a repair zone with undercuts prepared by water-jet technology. The presented numerical and experimental sensitivity analyses make a contribution to the systematic development of the interlock repair technology with respect to material and geometrical factors of influence. The results show the ability of the novel concept for a reproducible and automatable composite repair.

  9. Protein/CaCO3/Chitin Nanofiber Complex Prepared from Crab Shells by Simple Mechanical Treatment and Its Effect on Plant Growth

    Directory of Open Access Journals (Sweden)

    Yihun Fantahun Aklog

    2016-09-01

    Full Text Available A protein/CaCO3/chitin nanofiber complex was prepared from crab shells by a simple mechanical treatment with a high-pressure water-jet (HPWJ system. The preparation process did not involve chemical treatments, such as removal of protein and calcium carbonate with sodium hydroxide and hydrochloric acid, respectively. Thus, it was economically and environmentally friendly. The nanofibers obtained had uniform width and dispersed homogeneously in water. Nanofibers were characterized in morphology, transparency, and viscosity. Results indicated that the shell was mostly disintegrated into nanofibers at above five cycles of the HPWJ system. The chemical structure of the nanofiber was maintained even after extensive mechanical treatments. Subsequently, the nanofiber complex was found to improve the growth of tomatoes in a hydroponics system, suggesting the mechanical treatments efficiently released minerals into the system. The homogeneous dispersion of the nanofiber complex enabled easier application as a fertilizer compared to the crab shell flakes.

  10. INVESTIGATION ON NEW TYPE OF DOUBLY BLENDING ABRASIVE WATER JET NOZZLE SYSTEM WITH HIGHER PERFORMANCE

    Institute of Scientific and Technical Information of China (English)

    ZHU Pailong; ZHOU Jinjin; TANG Dianbo

    2006-01-01

    Based on the two existing abrasive water-jet(AWJ) systems, the dia-jet (or pre-jet) and the post-jet, a new type of abrasive water-jet system is put forward, which combines the dia-jet's advantage, low operating system pressure, slender stream jet, and more concentrative abrasive in the blended stream, with merits of post-jet, the less sophisticate apparatus, successive supply of abrasives.The theoretic analysis is brought out in detail, and the nozzle system structure is concisely illustrated.Its relevant experiment results are demonstrated, proving that this new system is effective in various aspects, enlarging penetrating capability without raising system pressure, saving machining power supply, lessening energy loss, etc.

  11. Perspective on peroral endoscopic myotomy for achalasia: Zhongshan experience.

    Science.gov (United States)

    Li, Quan Lin; Zhou, Ping Hong

    2015-03-01

    Worldwide, peroral endoscopic myotomy (POEM) has achieved remarkable initial outcomes in the treatment of achalasia. In China, POEM has developed very quickly since the first case was performed in our center in August 2010. With ex-perience, we have successfully performed POEM for special cases (such as pediatric patients, patients with sigmoid-type esophagus, and patients with recurrent symptoms after previous surgery) and have altered our technique to achieve long-term symptom remission and simplify the POEM proce-dure. These changes include posterior wall incision, full-thick-ness myotomy, a "push-and-pull" technique for myotomy, and water-jet assisted POEM. In this article, our experiences in POEM are summarized, including changes in technique, ap-plications of the procedure, and the management of possible complications. (Gut Liver, 2015;9:152-158).

  12. The Versajet water dissector: a new tool for tangential excision.

    Science.gov (United States)

    Klein, Matthew B; Hunter, Sue; Heimbach, David M; Engrav, Loren H; Honari, Shari; Gallery, Ellen; Kiriluk, Diane-Marie; Gibran, Nicole S

    2005-01-01

    Goulian and Watson knives work well for tangential burn excision on large flat areas. They do not work well in small areas and in areas with a three-dimensional structure. The Versajet Hydrosurgery System (Smith and Nephew, Key Largo, FL) is a new waterjet-powered surgical tool designed for wound excision. The small size of the cutting nozzle and the ability to easily maneuver the water dissector into small spaces makes it a potentially useful tool for excision of burns of the eyelids, digits and web spaces. The Versajet Hydrosurgery System contains a power console that propels saline through a handheld cutting device. This stream of pressurized saline functions as a knife. We have used the Versajet for burn excision in 44 patients. Although there is a learning curve for both surgeons using and operating room staff setting up the device, the Versajet provides a relatively facile method for excision of challenging aesthetic and functional areas.

  13. Influence of methylene blue-mediated photodynamic therapy on the resistance to detachment of streptococcus mutans biofilms from titanium substrata

    Science.gov (United States)

    Sharab, Lina Y.

    In dental settings, as well as in other natural systems, plaque-forming microorganisms develop biofilms in which the microbes become protected via their own phenotypic changes and their polymeric exudates from disinfection by washes and antibiotics. Photodynamic Therapy (PDT) is variably effective against these microorganisms, depending on such factors as whether the bacteria are Gram positive or Gram negative, plaque age and thickness, and internal biofilm oxygen concentration. This investigation applied a novel combination of PDT and water-jet impingement techniques to Streptococcus mutans (ATCC strain 27351)-formed biofilms on commercially pure titanium (cpTi) starting with three different phases (ages) of the bacteria, to examine whether the detachment shear stress --as a signature for the work required for removal of the biofilms- would be affected by prior PDT treatment independently from microbial viability. Biofilms were grown with sucrose addition to Brain Heart Infusion media, producing visible thick films and nearly invisible thin films (within the same piece) having the same numbers of culturable microorganisms, the thicker films having greater susceptibility to detachment by water--jet impingement. Colony-forming-unit (CFU) counts routinely correlated well with results from a spectrophotometric Alamar Blue (AB) assay. Use of Methylene Blue (MB) as a photosensitizer (PS) for PDT of biofilms did not interfere with the AB assay, but did mask AB reduction spectral changes when employed with planktonic organisms. It was discovered in this work that PD-treated microbial biofilms, independently from starting or PS-influenced microorganism viability, were significantly (p<0.05) and differentially more easily delaminated and ultimately removed from their substrata biomaterials by the hydrodynamic forces of water-jet impingement. Control biofilms of varying thickness, not receiving PDT treatment, required between 144 and 228 dynes/cm2 of shear stress to

  14. Advanced processing of the Zerodur R glass ceramic

    Science.gov (United States)

    Marx, Thomas A.

    1991-11-01

    The Zerodur glass ceramic is an extraordinary material possessing a very low thermal expansion over a broad temperature range. Depending on the size of the castings, a continuous or a discontinuous melting technology is used in the manufacture of Zerodur. Continuous melters are being operated regularly in Germany and recently in the United States. The latest generation of discontinuous melters started production of 8.2 m spincast telescope blanks in early 1991. Zerodur fusion is a special process to generate lightweighted mirror blanks and special components. It requires glassy material and generates bonds that are as strong as the bulk material. Further process development such as waterjet cutting and insertion technologies are underway and may generate components of unique shapes and performance.

  15. The root caused analysis of leakaged heat exchanger tube; Ursachenanalyse einer Leckage an einem Waermeuebertraegerrohr

    Energy Technology Data Exchange (ETDEWEB)

    Shamsudin, Shaiful Rizam; Salleh, M.A.A. Mohd; Rahmat, Azmi; Anuar, Mohd Arif [Universiti Malaysia Perlis (UniMAP) (Malaysia). Center of Excellence Geopolymer and Green Technology (CEGeoGTech); Harun, Mohd; Zayid, Hafizal [Malaysian Nuclear Agency, Selangor (Malaysia). Industry Technology Div.; Noor, Mazlee Mohd [Universiti Malaysia Perlis (UniMAP) (Malaysia). School of Materials Engineering

    2015-05-01

    AISI type 316L stainless steel was used as a heat exchanger tube material in an inter-cooler column. After less than a year of operation, severe corrosion failures occurred and a transverse opening leakage was observed on one of the heat exchanger tubes. The failed tube was carefully analyzed using various metallurgical laboratory equipments. The root cause of the tube leakage was believed due to the presence of horizontal micro and macro pores as a hydrogen gas entrapment during casting of the parent ingot. The overlapped and gaping pores formed notch on the shell side of the tube surface, and it increasingly evident when the use of a high-energy water-jet and metal brush as cleaning procedure results in an establishment of pitting type local-action corrosion cells penetrated the tube wall. As a result, corrosive fluid in the tube side dissolved into the cooling water, accelerating the corrosion process.

  16. Resistance and Seakeeping Numerical Performance Analyses of a Semi-Small Waterplane Area Twin Hull at Medium to High Speeds

    Institute of Scientific and Technical Information of China (English)

    Giuliano Vernengo; Dario Bruzzone

    2016-01-01

    The hydrodynamic analysis of a new semi-small waterplane area twin hull (SWATH) suitable for various applications such as small and medium size passenger ferries is presented. This may be an attractive crossover configuration resulting from the merging of two classical shapes: a conventional SWATH and a fast catamaran. The final hull design exhibits a wedge-like waterline shape with the maximum beam at the stern; the hull ends with a very narrow entrance angle, has a prominent bulbous bow typical of SWATH vessels, and features full stern to arrange waterjet propellers. Our analysis aims to perform a preliminary assessment of the hydrodynamic performance of a hull with such a complex shape both in terms of resistance of the hull in calm water and seakeeping capability in regular head waves and compare the performance with that of a conventional SWATH. The analysis is performed using a boundary element method that was preliminarily validated on a conventional SWATH vessel.

  17. Experim ental research in plasma arc cutting engineering ceramics%工程陶瓷的等离子弧切割实验研究

    Institute of Scientific and Technical Information of China (English)

    徐文骥; 蒋希时; 金洙吉

    2001-01-01

    Based on the analysis of the present situation and the characteristics of the technology of laser cutting, abrasive water-jet cutting, WEDM on engineering ceramics, a new method-additional positive pole plasma arc cutting is offered. The feasibility of the method has been proved by experiments. The method has its own advantage and good prospect.%在分析采用激光、磨料水射流、电火花线切割等方法切割工程陶瓷技术的现状与特点的基础上,提出采用附加阳极等离子弧切割工程陶瓷的基本思想,通过实验证明上述方法可行且具有独特的优点,显示出良好的应用前景。

  18. 永磁柔性传动技术的节能改造应用研究%Energy Saving Reformation of Permanent-Magnet Flexible Drive Technology

    Institute of Scientific and Technical Information of China (English)

    王伊真

    2014-01-01

    The Thermal Power Plant of Masteel installed permanent magnet speed adjust device on its No.3 generator water-jet pump to transmit energy between motor and water pump through permanent magnet air gap, which forms a stable, reliable and energy-saving efficient brand-new speed adjust device.%马钢热电总厂3#机组射水泵改装了永磁调速装置,将电机和水泵之间的能量传递,通过永磁体气隙来完成,既稳定可靠,节能效果也非常明显,是一项全新的调速节能装置。

  19. Optimal Control of Water Jet Cutting System Based on Pressure Sensor%基于压力传感器的水刀切割优化控制系统

    Institute of Scientific and Technical Information of China (English)

    徐礼龙; 赵德安; 于雯

    2012-01-01

    Considering the fact that water jetting speed, pressure, sand diameter, friction velocity and nozzle' 8 geometric parameters can influence the quality of cutting parts respectively, of which, only water jetting speed can be controlled freely, a pressure sensor-based optimal control system for water-jetting cutting process was proposed.%水刀切割工件质量与水刀的速度、喷流压力、砂粒直径、流量摩擦流速及喷嘴的几何参数等有关,但是只有速度可以随意控制,笔者设计一种基于压力传感器的水刀切割优化系统,解决了水射流技术存在的缺点.

  20. Enabling Tool for Innovative Glass Applications - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    James M. Gillis

    2005-11-16

    The use of abrasive waterjet (AWJ) cutting systems in the industrial sector has been limited to applications that are difficult to machine using conventional methods. A major factor for this limited use is the high cost of the garnet abrasive currently used. Initial studies indicated that glass can be processed to produce particles with the desired characteristics at a fraction of the existing price of garnet. Inexpensive abrasive waterjet cutting systems would allow a wider array of glass products to be produced while eliminating many existing design limitations. Availability of low-cost abrasive waterjet cutting media would open new markets for glass applications by making glass a more versatile material. A fundamental goal of this project was to scale up and refine the circuit that was established in the initial phase of this project, which using waste glass as a feed stream, could economically produce glass particles displaying high angularity, sharp edges and a low aspect ratio which would prove suitable for use in abrasive waterjet (AWJ) cutting systems. Using commercial scale equipment, demonstration runs were conducted at various manufacturers facilities to further establish that waste glass is a viable source for the production of an inexpensive AWJ media for use in cutting glass and a variety of other materials. The glass abrasive produced was used to demonstrate that processed waste glass could serve as a less costly alternative to garnet in many AWJ cutting applications. Studies indicated that glass can be processed to produce particles with the desired characteristics at less than 1% of the existing price of garnet. The waste stream resulting from the use of the glass abrasive in an AWJ system was in turn used as a source for inexpensive fillers in various polymers. The reduced energy requirements needed to produce glass abrasives and lower cost associated with the use of waste glass over garnet, as well as the environmental benefits associated with

  1. A Study on the Pressure Relief Scope and the Stress Variation of Hydraulic Flushing Borehole

    Directory of Open Access Journals (Sweden)

    C. F.Wei

    2014-01-01

    Full Text Available To study the variation of the pressure relief scope and the stress around hydraulic flushing borehole, the theory of coalrock damage was utilized to distinguish the interaction area of water-jet and coal-rock into the coal-rock crushing area, the water-jet pressure stagnation area, the transition area and the original stress recovery area of coal-rock. Based on the actual occurrence conditions of the coal seam, the pressure variation and relief scope around the hydraulic flushing borehole were analyzed and simulated by RFPA2D-Flow software. The results showed that a relief area with the radius of 5.0 ~ 6.0 m around the borehole formed due to the hydraulic flushing with the pressure relief of 0.038 ~ 6.545 MPa, and the maximum principal stress is 15.85 MPa with a distance of 6.8 m from the inspected hole where stress concentration appeared. After hydraulic flushing test, the diameter (441.8 ~ 1171.6 mm of the hole which can be an expression of coal crushing area size, was calculated based on the examination of the coal amount through the trial process, and it can be drawn that the pressure relief area must be larger than that of the coal-rock crushing area. Meanwhile, the measured pressures relief range(5.96 ~ 6.62 m is basically consistent with the numerical simulation result (5.0 ~ 6.0 m which verified the accuracy of the simulation analysis, according to the distance from the inspection drilling to the hydraulic flushing borehole and the decreased degree of the gas content in the inspection hole by the way of Gas Content.

  2. HYDRODISSECTION FOR PRESERVATION OF NEUROVASCULAR BUNDLE DURING RADICAL PROSTATECTOMY

    Directory of Open Access Journals (Sweden)

    H. S. Gevorgyan

    2016-01-01

    Full Text Available Nerve-sparing radical prostatectomy is one of the high-tech operations in urology, and the challenge of the surgeon is not only to remove the prostate tumor, but also to provide a high quality of life. The fact that most questions devoted from patients in a conversation with the surgeon before the operation are devoted to this issue, shows the importance and relevance. At present, the diagnostic methods allow significantly more likely to detect early  prostate cancer, making finding and treatment of these patients more affordable and allows to apply this operation.Lately, it seems urgent to explore the possibility of water jet dissection in the field of urology, in particular, for nerve-sparing prostatectomy. Preservation of erectile function depends largely on the quality of separating the neurovascular bundle. Standard use of electrocautery is associated with damage to the neurovascular bundle.  When performing operations using water-jet mobilization of prostate the selective dissection of tissue is performed. This avoids injury of neurovascular bundle and further postoperative complications. The use of this technique may allow the surgeon to provide a more accurate mobilization prostate and selectively controlled intersection vessels heading to the prostate from the neurovascular bundle, reduce intraoperative blood loss,  maintaining continence, erectile function.This literature review is considered by the experience of using nerve-sparing radical prostatectomy using a water-jet dissector, estimated intraoperative parameters using this method.However, we have the lack of extensive research capabilities of this technique when performing nerve-preserving radical prostatectomy, that does not allow to make a comprehensive presentation on the benefits of this technique and its effects on erectile function and quality of urination, further study of this issue in such a difficult category of patients.

  3. Oak Ridge National Laboratory Old Hydrofracture Facility Waste Remediation Using the Borehole-Miner Extendible-Nozzle Sluicer

    Energy Technology Data Exchange (ETDEWEB)

    Bamberger, J.A.; Boris, G.F.

    1999-10-07

    A borehole-miner extendible-nozzle sluicing system was designed, constructed, and deployed at Oak Ridge National Laboratory to remediate five horizontal underground storage tanks containing sludge and supernate at the ORNL Old Hydrofracture Facility site. The tanks were remediated in fiscal year 1998 to remove {approx}98% of the waste, {approx}3% greater than the target removal of >95% of the waste. The tanks contained up to 18 in. of sludge covered by supernate. The 42,000 gal of low level liquid waste were estimated to contain 30,000 Ci, with 97% of this total located in the sludge. The retrieval was successful. At the completion of the remediation, the State of Tennessee Department of Environment and Conservation agreed that the tanks were cleaned to the maximum extent practicable using pumping technology. This deployment was the first radioactive demonstration of the borehole-miner extendible-nozzle water-jetting system. The extendible nozzle is based on existing bore hole-miner technology used to fracture and dislodge ore deposits in mines. Typically borehole-miner technology includes both dislodging and retrieval capabilities. Both dislodging, using the extendible-nozzle water-jetting system, and retrieval, using a jet pump located at the base of the mast, are deployed as an integrated system through one borehole or riser. Note that the extendible-nozzle system for Oak Ridge remediation only incorporated the dislodging capability; the retrieval pump was deployed through a separate riser. The borehole-miner development and deployment is part of the Retrieval Process Development and Enhancements project under the direction of the US Department of Energy's EM-50 Tanks Focus Area. This development and deployment was conducted as a partnership between RPD and E and the Oak Ridge National Laboratory's US DOE EM040 Old Hydrofracture Facility remediation project team.

  4. Numerical Modeling for Hole-Edge Cracking of Advanced High-Strength Steels (AHSS) Components in the Static Bend Test

    Science.gov (United States)

    Kim, Hyunok; Mohr, William; Yang, Yu-Ping; Zelenak, Paul; Kimchi, Menachem

    2011-08-01

    Numerical modeling of local formability, such as hole-edge cracking and shear fracture in bending of AHSS, is one of the challenging issues for simulation engineers for prediction and evaluation of stamping and crash performance of materials. This is because continuum-mechanics-based finite element method (FEM) modeling requires additional input data, "failure criteria" to predict the local formability limit of materials, in addition to the material flow stress data input for simulation. This paper presents a numerical modeling approach for predicting hole-edge failures during static bend tests of AHSS structures. A local-strain-based failure criterion and a stress-triaxiality-based failure criterion were developed and implemented in LS-DYNA simulation code to predict hole-edge failures in component bend tests. The holes were prepared using two different methods: mechanical punching and water-jet cutting. In the component bend tests, the water-jet trimmed hole showed delayed fracture at the hole-edges, while the mechanical punched hole showed early fracture as the bending angle increased. In comparing the numerical modeling and test results, the load-displacement curve, the displacement at the onset of cracking, and the final crack shape/length were used. Both failure criteria also enable the numerical model to differentiate between the local formability limit of mechanical-punched and water-jet-trimmed holes. The failure criteria and static bend test developed here are useful to evaluate the local formability limit at a structural component level for automotive crash tests.

  5. Magnetically Attached Multifunction Maintenance Rover

    Science.gov (United States)

    Bar-Cohen, Yoseph; Joffe, Benjamin

    2005-01-01

    A versatile mobile telerobot, denoted the magnetically attached multifunction maintenance rover (MAGMER), has been proposed for use in the inspection and maintenance of the surfaces of ships, tanks containing petrochemicals, and other large ferromagnetic structures. As its name suggests, this robot would utilize magnetic attraction to adhere to a structure. As it moved along the surface of the structure, the MAGMER would perform tasks that could include close-up visual inspection by use of video cameras, various sensors, and/or removal of paint by water-jet blasting, laser heating, or induction heating. The water-jet nozzles would be mounted coaxially within compressed-air-powered venturi nozzles that would collect the paint debris dislodged by the jets. The MAGMER would be deployed, powered, and controlled from a truck, to which it would be connected by hoses for water, compressed air, and collection of debris and by cables for electric power and communication (see Figure 1). The operation of the MAGMER on a typical large structure would necessitate the use of long cables and hoses, which can be heavy. To reduce the load of the hoses and cables on the MAGMER and thereby ensure its ability to adhere to vertical and overhanging surfaces, the hoses and cables would be paid out through telescopic booms that would be parts of a MAGMER support system. The MAGMER would move by use of four motorized, steerable wheels, each of which would be mounted in an assembly that would include permanent magnets and four pole pieces (see Figure 2). The wheels would protrude from between the pole pieces by only about 3 mm, so that the gap between the pole pieces and the ferromagnetic surface would be just large enough to permit motion along the surface but not so large as to reduce the magnetic attraction excessively. In addition to the wheel assemblies, the MAGMER would include magnetic adherence enhancement fixtures, which would comprise arrays of permanent magnets and pole pieces

  6. Evaluation of Shear Strength Threshold of Concern for Retrieval of Interim-Stored K-Basin Sludge in the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Yasuo; Yokuda, Satoru T.; Schmidt, Andrew J.

    2010-11-01

    K-Basin sludge will be recovered into the Sludge Transport and Storage Containers (STSCs) and will be stored in the T Plant for interim storage (at least 10 years). Long-term sludge storage tests conducted by Pacific Northwest National Laboratory show that high uranium content K Basin sludge can self-cement and form a strong sludge with a bulk shear strength of up to 65 kPa. Some of this sludge has "paste" and "chunks" with shear strengths of approximately 3~5 kPa and 380 ~ 770 kPa, respectively. High uranium content sludge samples subjected to hydrothermal testing (e.g., 185°C, 10 h) have been observed to form agglomerates with a shear strength up to 170 kPa. After interim storage at T Plant, the sludge in the STSCs will be mobilized by water jets impinging the sludge. The objective of the evaluation was to determine the range of sludge shear strength for which there is high confidence that a water-jet retrieval system can mobilize stored K-Basin sludge from STSCs. The shear strength at which the sludge can be retrieved is defined as the "shear strength threshold of concern." If the sludge shear strength is greater than the value of the shear strength threshold of concern, a water-jet retrieval system will be unlikely to mobilize the sludge up to the container’s walls. The shear strength threshold of concern can be compared with the range of possible shear strengths of K-Basin stored sludge to determine if the current post interim-storage, water-jet retrieval method is adequate. Fourteen effective cleaning radius (ECR) models were reviewed, and their validity was examined by applying them to Hanford 241-SY-101 and 241-AZ-101 Tanks to reproduce the measured ECR produced by the mixer pumps. The validation test identified that the Powell-3 and Crowe-2 ECR models are more accurate than other ECR models reviewed. These ECR models were used to address a question as to whether the effective cleaning radius of a water jet is sufficient or if it can be readily expanded

  7. Metallurgical Evaluations of Depainting Processes on Aluminum Substrate

    Science.gov (United States)

    McGill, Preston

    1999-01-01

    In December 1993, the Environmental Protection Agency (EPA) Emission Standards Division and the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC) signed an Interagency Agreement (IA) initiating a task force for the technical assessment of alternative technologies for aerospace depainting operations. The United States Air Force (USAF) joined the task force in 1994. The mandates of the task force were: (1) To identify available alternative depainting systems that do not rely on methylene chloride or other ozone-depleting, chlorinated, and volatile organic carbon solvents. (2) To determine the viability, applicability, and pollution prevention potential of each identified alternative. (3) To address issues of safety, environmental impact, reliability, and maintainability. Through a Technical Implementation Committee (TIC), the task force selected and evaluated eight alternative paint stripping technologies: chemical stripping, carbon dioxide (CO2) blasting, xenon flashlamp and CO2 coatings removal (FLASHJET(R)), CO2 laser stripping, plastic media blasting (PMB), sodium bicarbonate wet stripping, high-pressure water blasting (WaterJet), and wheat starch abrasive blasting (Enviro-Strip(R)). (The CO2 blasting study was discontinued after the first depainting sequence.) This final report presents the results of the Joint EPA/NASA/USAF Interagency Depainting Study. Significant topics include: (1) Final depainting sequence data for the chemical stripping, PMB, sodium bicarbonate wet stripping, and WaterJet processes. (2) Strip rates for all eight technologies. (3) Sequential comparisons of surface roughness measurements for the seven viable depainting technologies. (4) Chronological reviews of and lessons learned in the conduct of all eight technologies. (5) An analysis of the surface roughness trends for each of the seven technologies. (6) Metallurgic evaluations of panels Summaries of corrosion and hydrogen embrittlement

  8. Isolation and differentiation potential of human mesenchymal stem cells from adipose tissue harvested by water jet-assisted liposuction.

    Science.gov (United States)

    Meyer, Juliane; Salamon, Achim; Herzmann, Nicole; Adam, Stefanie; Kleine, Hans-Dieter; Matthiesen, Inge; Ueberreiter, Klaus; Peters, Kirsten

    2015-11-01

    In recent years the therapeutic application of extracted adipose tissue for autologous fat grafting and the application of adipose tissue-derived mesenchymal stem cells (adMSC) isolated thereof has progressed. Water-jet assisted liposuction (WAL) is 1 procedure for harvesting adipose tissue and provides a favorable aesthetic outcome combined with high tissue protection. Tissue aspirated by WAL has been successfully applied in grafting procedures. The aims of this study were to confirm the tissue viability and to understand the abundance and mesenchymal differentiation capacity of stem cells within the tissue. We analyzed tissue integrity of WAL tissue particles via fluorescence microscopy. The adMSC content was determined by isolating the cells from the tissue. The mesenchymal differentiation capacity was confirmed with cytochemical staining methods. The stromal vascular fraction of WAL tissue showed high viability and contained an average of 2.6 × 105 CD34-positive cells per milliliter of tissue. Thus WAL tissue contains a high number of stem cells. Furthermore adMSC isolated from WAL tissue showed typical mesenchymal differentiation potential. WAL of adipose tissue is well suited for autologous fat grafting because it retains tissue viability. Furthermore it is a valid source for the subsequent isolation of adMSC with multipotent differentiation potential. 3 Therapeutic. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  9. Pressurized-water reactor internals aging degradation study. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Luk, K.H. [Oak Ridge National Lab., TN (United States)

    1993-09-01

    This report documents the results of a Phase I study on the effects of aging degradations on pr internals. Primary stressers for internals an generated by the primary coolant flow in the they include unsteady hydrodynamic forces and pump-generated pressure pulsations. Other stressors are applied loads, manufacturing processes, impurities in the coolant and exposures to fast neutron fluxes. A survey of reported aging-related failure information indicates that fatigue, stress corrosion cracking (SCC) and mechanical wear are the three major aging-related degradation mechanisms for PWR internals. Significant reported failures include thermal shield flow-induced vibration problems, SCC in guide tube support pins and core support structure bolts, fatigue-induced core baffle water-jet impingement problems and excess wear in flux thimbles. Many of the reported problems have been resolved by accepted engineering practices. Uncertainties remain in the assessment of long-term neutron irradiation effects and environmental factors in high-cycle fatigue failures. Reactor internals are examined by visual inspections and the technique is access limited. Improved inspection methods, especially one with an early failure detection capability, can enhance the safety and efficiency of reactor operations.

  10. Development of a molecular-dynamics-based cluster-heat-capacity model for study of homogeneous condensation in supersonic water-vapor expansions.

    Science.gov (United States)

    Borner, Arnaud; Li, Zheng; Levin, Deborah A

    2013-02-14

    Supersonic expansions to vacuum produce clusters of sufficiently small size that properties such as heat capacities and latent heat of evaporation cannot be described by bulk vapor thermodynamic values. In this work the Monte-Carlo Canonical-Ensemble (MCCE) method was used to provide potential energies and constant-volume heat capacities for small water clusters. The cluster structures obtained using the well-known simple point charge model were found to agree well with earlier simulations using more rigorous potentials. The MCCE results were used as the starting point for molecular dynamics simulations of the evaporation rate as a function of cluster temperature and size which were found to agree with unimolecular dissociation theory and classical nucleation theory. The heat capacities and latent heat obtained from the MCCE simulations were used in direct-simulation Monte-Carlo of two experiments that measured Rayleigh scattering and terminal dimer mole fraction of supersonic water-jet expansions. Water-cluster temperature and size were found to be influenced by the use of kinetic rather than thermodynamic heat-capacity and latent-heat values as well as the nucleation model.

  11. A Novel Method for Borehole Blockage Removal and Experimental Study on a Hydraulic Self-Propelled Nozzle in Underground Coal Mines

    Directory of Open Access Journals (Sweden)

    Zhaolong Ge

    2016-08-01

    Full Text Available When coal bed methane (CBM drainage boreholes cross fractured, soft, or water-swelling strata, they collapse and block frequently. Borehole blockages result in a rapid decrease in CBM extraction ability, which leads to a reduction in CBM output and threatens coal mine safety production. To solve these problems, a novel method that uses a self-propelled water-jet nozzle to dredge blocked boreholes in coal seams has been proposed on the basis of the existing technology. Based on a theoretical analysis of the reason for borehole caving and the theory of blockage removal, we optimized the nozzle inlet pressure and selected an appropriate high-pressure resin pipe. A field experiment on the blockage removal of blocked CBM drainage boreholes using the proposed method was run in the Fengchun coal mine, Qijiang, Chongqing, southwest China. In this field trial, the time spent to unblock a borehole varied between 18.52 and 34.98 min, which is much shorter than using a drilling rig. After blockage removal, the average pure volume of the methane drainage of a single borehole was increased from 0.03 L/min to ~1.91–7.30 L/min, and the methane drainage concentration of a single borehole increased from 5% to ~44%–85%. The extraction effect increased significantly.

  12. Enhancement and Prediction of Adhesion Strength of Copper Cold Spray Coatings on Steel Substrates for Nuclear Fuel Repository

    Science.gov (United States)

    Fernández, R.; MacDonald, D.; Nastić, A.; Jodoin, B.; Tieu, A.; Vijay, M.

    2016-12-01

    Thick copper coatings have been envisioned as corrosion protection barriers for steel containers used in repositories for nuclear waste fuel bundles. Due to its high deposition rate and low oxidation levels, cold spray is considered as an option to produce these coatings as an alternative to traditional machining processes to create corrosion protective sleeves. Previous investigations on the deposition of thick cold spray copper coatings using only nitrogen as process gas on carbon steel substrates have continuously resulted in coating delamination. The current work demonstrates the possibility of using an innovative surface preparation process, forced pulsed waterjet, to induce a complex substrate surface morphology that serves as anchoring points for the copper particles to mechanically adhere to the substrate. The results of this work show that, through the use of this surface preparation method, adhesion strength can be drastically increased, and thick copper coatings can be deposited using nitrogen. Through finite element analysis, it was shown that it is likely that the bonding created is purely mechanical, explaining the lack of adhesion when conventional substrate preparation methods are used and why helium is usually required as process gas.

  13. [A simple apparatus for the determination of the resistance of bioindicators to saturated steam at temperatures less than 100 degrees C., tested with Enterococcus faecium as test microbe].

    Science.gov (United States)

    Spicher, G; Borchers, U; Peters, J

    1991-09-01

    An apparatus is described by means of which the resistance of microbiological indicators to water vapor at temperatures below 100 degrees C can be determined. The apparatus can be assembled from parts generally available in laboratories. The principle of the apparatus consists in the production of water vapor of the desired temperature under conditions of reduced pressure and its recondensation to water after having passed a special chamber. Accordingly, the device consists of a heated round-bottom flask serving as steam generator, an exposure chamber (B), and a condenser (D) attached to a receiver (E). The bioindicators are exposed to the water vapor in the exposure chamber. A bypass located between the steam generator and the condenser allows for continuous operation even when the exposure chamber is opened. The reduced pressure was achieved by means of a waterjet pump and adjusted by two tandem-joined pressure-regulating valves as needed. The apparatus was tested using water vapor of 73, 75 and 77 degrees C, respectively, and bioindicators containing Enterococcus faecium as test organism. In the range of exposure periods in which bioindicators change from the status "all indicators having surviving test organisms" to the status "all indicators free from surviving test organisms" the bioindicators showed D values of 5.7, 4.4 and 2.9 min, respectively. For the temperature dependence of resistance a z value of 12.5 Kelvin resulted.

  14. Adipose mesenchymal stem cells isolated after manual or water jet-assisted liposuction display similar properties

    Directory of Open Access Journals (Sweden)

    Claire eBony

    2016-01-01

    Full Text Available Mesenchymal stem or stromal cells (MSC are under investigation in many clinical trials for their therapeutic potential in a variety of diseases, including autoimmune and inflammatory disorders. One of the main sources of MSCs is the adipose tissue, which is mainly obtained by manual liposuction using a cannula linked to a syringe. However, in the last years, a number of devices for fat liposuction intended for clinical use have been commercialized but few papers have compared these procedures in terms of stromal vascular fraction (SVF or adipose stromal cells (ASC. The objective of the present study was to compare and qualify for clinical use the adipose stromal cells (ASC obtained from fat isolated with the manual or the Bodyjet® waterjet-assisted procedure. Although the initial number of cells after collagenase digestion was higher with the manual procedure, both the percentage of dead cells, the number of CFU-F and the phenotype of cells were identical in the SVF at isolation and in the ASC populations at day 14. We also showed that the osteogenic and adipogenic differentiation potentials of ASCs were identical between preparations while a slight but significant higher in vitro immunosuppressive effect was observed with ASCs isolated from fat removed with a cannula. The difference in the immunomodulatory effect between ASC populations was however not observed in vivo using the delayed-type hypersensitivity model. Our data therefore indicate that the procedure for fat liposuction does not impact the characteristics or the therapeutic function of ASCs.

  15. Application of multi-stage Monte Carlo method for solving machining optimization problems

    Directory of Open Access Journals (Sweden)

    Miloš Madić

    2014-08-01

    Full Text Available Enhancing the overall machining performance implies optimization of machining processes, i.e. determination of optimal machining parameters combination. Optimization of machining processes is an active field of research where different optimization methods are being used to determine an optimal combination of different machining parameters. In this paper, multi-stage Monte Carlo (MC method was employed to determine optimal combinations of machining parameters for six machining processes, i.e. drilling, turning, turn-milling, abrasive waterjet machining, electrochemical discharge machining and electrochemical micromachining. Optimization solutions obtained by using multi-stage MC method were compared with the optimization solutions of past researchers obtained by using meta-heuristic optimization methods, e.g. genetic algorithm, simulated annealing algorithm, artificial bee colony algorithm and teaching learning based optimization algorithm. The obtained results prove the applicability and suitability of the multi-stage MC method for solving machining optimization problems with up to four independent variables. Specific features, merits and drawbacks of the MC method were also discussed.

  16. Optimization of machining processes using pattern search algorithm

    Directory of Open Access Journals (Sweden)

    Miloš Madić

    2014-04-01

    Full Text Available Optimization of machining processes not only increases machining efficiency and economics, but also the end product quality. In recent years, among the traditional optimization methods, stochastic direct search optimization methods such as meta-heuristic algorithms are being increasingly applied for solving machining optimization problems. Their ability to deal with complex, multi-dimensional and ill-behaved optimization problems made them the preferred optimization tool by most researchers and practitioners. This paper introduces the use of pattern search (PS algorithm, as a deterministic direct search optimization method, for solving machining optimization problems. To analyze the applicability and performance of the PS algorithm, six case studies of machining optimization problems, both single and multi-objective, were considered. The PS algorithm was employed to determine optimal combinations of machining parameters for different machining processes such as abrasive waterjet machining, turning, turn-milling, drilling, electrical discharge machining and wire electrical discharge machining. In each case study the optimization solutions obtained by the PS algorithm were compared with the optimization solutions that had been determined by past researchers using meta-heuristic algorithms. Analysis of obtained optimization results indicates that the PS algorithm is very applicable for solving machining optimization problems showing good competitive potential against stochastic direct search methods such as meta-heuristic algorithms. Specific features and merits of the PS algorithm were also discussed.

  17. ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION

    Energy Technology Data Exchange (ETDEWEB)

    Dr. David J. Bayless; Dr. Morgan Vis; Dr. Gregory Kremer; Dr. Michael Prudich; Dr. Keith Cooksey; Dr. Jeff Muhs

    2001-01-16

    This is the first quarterly report of the project Enhanced Practical Photosynthetic CO{sub 2} Mitigation. The official project start date, 10/02/2000, was delayed until 10/31/2000 due to an intellectual property dispute that was resolved. However, the delay forced a subsequent delay in subcontracting with Montana State University, which then delayed obtaining a sampling permit from Yellowstone National Park. However, even with these delays, the project moved forward with some success. Accomplishments for this quarter include: Culturing of thermophilic organisms from Yellowstone; Testing of mesophilic organisms in extreme CO{sub 2} conditions; Construction of a second test bed for additional testing; Purchase of a total carbon analyzer dedicated to the project; Construction of a lighting container for Oak Ridge National Laboratory optical fiber testing; Modified lighting of existing test box to provide more uniform distribution; Testing of growth surface adhesion and properties; Experimentation on water-jet harvesting techniques; and Literature review underway regarding uses of biomass after harvesting. Plans for next quarter's work and an update on the project's web page are included in the conclusions.

  18. Robots for Aircraft Maintenance

    Science.gov (United States)

    1993-01-01

    Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

  19. 推进剂粉尘点火特性及预防措施%Characteristic and Preventive Measures of Propellant Dust Ignition

    Institute of Scientific and Technical Information of China (English)

    郁红陶; 董静

    2012-01-01

    During high pressure wateriet impact propellant from solid -propellant rocket engine, there are some dangerous. The characteristic and influencing factor of propellant dust ignition were discussed from propellant explosion induced by dust ignition. The static electricity protection and dust concentration monitoring were proposed through analysis of working environment, so the safety of waterjet impact propellant is improved.%高压水射流清理固体火箭发动机中的推进剂时存在危险性,从粉尘点火诱发推进剂爆炸的角度出发,探讨了推进剂粉尘点火的特性和影响因素.通过对作业环境的分析,提出了静电防护和粉尘浓度监测两种主要措施,由此提高了水射流清理推进剂的安全性.

  20. VO2 prediction and cardiorespiratory responses during underwater treadmill exercise.

    Science.gov (United States)

    Greene, Nicholas P; Greene, Elizabeth S; Carbuhn, Aaron F; Green, John S; Crouse, Stephen F

    2011-06-01

    We compared cardiorespiratory responses to exercise on an underwater treadmill (UTM) and land treadmill (LTM) and derived an equation to estimate oxygen consumption (VO2) during UTM exercise. Fifty-five men and women completed one LTM and five UTM exercise sessions on separate days. The UTM sessions consisted of chest-deep immersion, with 0, 25, 50, 75, and 100% water-jet resistance. All session treadmill velocities increased every 3 min from 53.6 to 187.8 m x min(-1). Cardiorespiratory responses were similar between LTM and UTM when jet resistance for UTM was 50%. Using multiple regression analysis, weight-relative VO2 could be estimated as: VO2 (mLO2 c kg(-1) x min(-1)) = 0.19248 x height (cm) + 0.17422 x jet resistance (% max) + 0.14092 x velocity (m x min(-1)) -0.12794 x weight (kg)-27.82849, R2 = .82. Our data indicate that similar LTM and UTM cardiorespiratory responses are achievable, and we provide a reasonable estimate of UTM VO2.

  1. Hydrodynamic Analysis of the Spherical Underwater Robot SUR-II

    Directory of Open Access Journals (Sweden)

    Chunfeng Yue

    2013-05-01

    Full Text Available Abstract This paper describes the development of the second-generation Spherical Underwater Robot (SUR-II. The new SUR-II has an improved propulsion system structure, resulting in better performance compared with the original design. This paper focuses on the characteristics of the water-jet thruster and the spherical hull of the SUR-II. To analyse its hydrodynamic characteristics, the main hydrodynamic parameters of the SUR-II were estimated based on two reasonable assumptions and a reasonable dynamic equation was proposed to describe the relationship between force and velocity. Drag coefficients were calculated separately for vertical and horizontal motions due to the fin on the robot's equator and the holes in the robot's hull. The holes had a particularly adverse effect on the horizontal drag coefficient. A hydrodynamic analysis using computational fluid dynamics was then carried out to verify the estimated parameters. The velocity vectors, pressure contours and drag coefficient for each state of motion were obtained. Finally, the propulsive force was determined experimentally to verify the theoretical calculations and simulation results.

  2. Fiscal 1998 achievement report on regional consortium research and development project. Venture business fostering regional consortium--Creation of key industries (Research and development of emission-free material separation and recycling process technologies for spent electric/electronic products); 1998 nendo shiyozomi denki denshi kogyo seihin no emissionless sozai bunri saisei junkan system no kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The personal computer is taken up as a sample, and studies are conducted about a system for separating and recovering recyclable materials. For the high-speed cutting and crushing of materials and their compaction, a water-jet cutting method is employed, which enables the unification of chip sizes after cutting, the prevention of dust generation, and the realization of clean working environments. For the separation of copper wires from their coats, a high-speed peeling machine is developed, and the copper wires are recovered for reuse. Fluorine plastics and polyester resin that constitute the coats do not show deterioration in their resin properties when put back into use. As for the powder resulting from the crushing of print circuit boards, it produces gas and unburnt carbon when subjected to heat treatment at 600 degrees C in inactive gas. The problem to arise from this recovery method is how to lower the cost. The separation of pelletized polymers and metal constituents can be accomplished by changing the ablation generation limit energy level during excimer laser irradiation, and this allows them to be recycled. (NEDO)

  3. Joint EPA/NASA/USAF Interagency Depainting Study

    Science.gov (United States)

    Clark-Ingram, M.

    2001-01-01

    Environmental regulations such as National Emission Standards for Hazardous Air Pollutants (NESHAPs) are drivers for the implementation of environmentally compliant methodologies in the manufacture of aerospace hardware. In 1995, the Environmental Protection Agency (EPA) promulgated the NESHAP for the Aerospace Manufacture and Rework (Aerospace NESHAP) industry. Affected facilities were to be in compliance by September 1998. Several aerospace manufacturing operations are regulated within the Aerospace NESHAP including Depainting operations. The National Aeronautics and Space Administration (NASA), EPA, and United States Air Force (USAF) combined resources to evaluate the performance of nine alternative depainting processes. The seven alternative depainting processes were: (1) Chemical stripping (non-methylene chloride); (2) Carbon Dioxide Blasting; (3) Xenon Flashlamp; (4) Carbon Dioxide Laser Stripping; (5) Plastic Media Blasting; (6) Sodium Bicarbonate Wet Stripping; and (7) Waterjet Blasting and Wheat Starch Blasting. All epoxy primer and polyurethane top coat system was applied to 2024-T3 clad and non-clad aluminum test specimens. Approximately 200 test specimens were evaluated in this study. Each coupon was subjected to three, four, or five complete depainting cycles. This paper discusses the conclusions from the study including the test protocol, test parameters, and achievable strip rates for the alternative depainting processes. Test data includes immersion corrosion testing, sandwich corrosion testing and hydrogen embrittlement testing for the non-methylene chloride chemical strippers. Additionally, the cumulative effect of the alternative depainting processes on the metallurgical integrity of the test substrate is addressed with the results from tensile and fatigue evaluations.

  4. Air flow exploration of abrasive feed tube

    Science.gov (United States)

    Zhang, Shijin; Li, Xiaohong; Gu, Yilei

    2009-12-01

    An abrasive water-jet cutting process is one in which water pressure is raised to a very high pressure and forced through a very small orifice to form a very thin high speed jet beam. This thin jet beam is then directed through a chamber and then fed into a secondary nozzle, or mixing tube. During this process, a vacuum is generated in the chamber, and garnet abrasives and air are pulled into the chamber, through an abrasive feed tube, and mixes with this high speed stream of water. Because of the restrictions introduced by the abrasive feed tube geometry, a vacuum gradient is generated along the tube. Although this phenomenon has been recognized and utilized as a way to monitor nozzle condition and abrasive flowing conditions, yet, until now, conditions inside the abrasive feed line have not been completely understood. A possible reason is that conditions inside the abrasive feed line are complicated. Not only compressible flow but also multi-phase, multi-component flow has been involved in inside of abrasive feed tube. This paper explored various aspects of the vacuum creation process in both the mixing chamber and the abrasive feed tube. Based on an experimental exploration, an analytical framework is presented to allow theoretical calculations of vacuum conditions in the abrasive feed tube.

  5. Functions and requirements for a waste dislodging and conveyance system for the gunite and associated tanks treatability study at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Potter, J.D.; Mullen, O.D.

    1997-02-01

    Since the mid 1940s, the Department of Defense (DOD) and the Department of Energy (DOE) have conducted research and development activities at the Oak Ridge National Laboratory (ORNL) in support of urgent national interests in the fields of nuclear weaponry and nuclear energy. Some of these activities resulted in radiologically hazardous waste being temporarily deposited at ORNL, Waste Area Grouping 1. At this location, waste is stored in several underground storage tanks, awaiting ultimate final disposal. There are tanks of two basic categories. One category is referred to as the gunite tanks, the other category is associated tanks. The ORNL Gunite and Associated Tanks Treatability Study (GAAT TS) project was initiated in FY 1994 to support a record of decision in selecting from seven different options of technologies for retrieval and remediation of these tanks. As part of this decision process, new waste retrieval technologies will be evaluated at the 25-foot diameter gunite tanks in the North tank farm. Work is currently being conducted at Hanford and the University of Missouri-Rolla to evaluate and develop some technologies having high probability of being most practical and effective for the dislodging and conveying of waste from underground storage tanks. The findings of these efforts indicate that a system comprised of a dislodging end effector employing jets of high-pressure fluids, coupled to a water-jet conveyance system, all carried above the waste by a mechanical arm or other mechanism, is a viable retrieval technology for the GAAT TS tasks.

  6. Unsteady penetration of a target by a liquid jet.

    Science.gov (United States)

    Uth, Tobias; Deshpande, Vikram S

    2013-12-10

    It is widely acknowledged that ceramic armor experiences an unsteady penetration response: an impacting projectile may erode on the surface of a ceramic target without substantial penetration for a significant amount of time and then suddenly start to penetrate the target. Although known for more than four decades, this phenomenon, commonly referred to as dwell, remains largely unexplained. Here, we use scaled analog experiments with a low-speed water jet and a soft, translucent target material to investigate dwell. The transient target response, in terms of depth of penetration and impact force, is captured using a high-speed camera in combination with a piezoelectric force sensor. We observe the phenomenon of dwell using a soft (noncracking) target material. The results show that the penetration rate increases when the flow of the impacting water jet is reversed due to the deformation of the jet-target interface--this reversal is also associated with an increase in the force exerted by the jet on the target. Creep penetration experiments with a constant indentation force did not show an increase in the penetration rate, confirming that flow reversal is the cause of the unsteady penetration rate. Our results suggest that dwell can occur in a ductile noncracking target due to flow reversal. This phenomenon of flow reversal is rather widespread and present in a wide range of impact situations, including water-jet cutting, needleless injection, and deposit removal via a fluid jet.

  7. Hydro-jet cutting: a method for selective surgical dissection of nerve tissue. An experimental study on the sciatic nerve of rats.

    Science.gov (United States)

    Kaduk, W M; Stengel, B; Pöhl, A; Nizze, H; Gundlach, K K

    1999-10-01

    The aim of this study was to answer the question: is it possible to save motor nerves when dissecting tissue with the hydro-jet dissector? In order to study the influence of the hydro-jet on motor nerves the function of the sciatic nerves of 10 Wistar rats was evaluated. The sciatic nerves were dissected bilaterally and only the left one was exposed to the hydro-jet. The water-jet emerged from a nozzle with a diameter of 0.1 mm and was applied to the nerve for 2, 5 or 10 s and with jet pressures of 80, 85 and 90 bar, respectively. After the operation the animals were observed for 5 months in order to monitor the degree of limping using a scale with 10 clinical grades of function. Five months postoperatively the animals were sacrificed and the sciatic nerves were studied by light and electron microscopy. It was found that hydro-jet pressures of 80 bar and exposure times of 2 s had already lead to irreversible damage to the sciatic nerve. Therefore further studies with lower pressures or shorter exposure times are required before considering hydro-jet cutting for parotid gland surgery. It must be confirmed as harmless to motor nerves before applying this method in humans.

  8. Distribution and inventories of fallout radionuclides ({sup 239+24}Pu, {sup 137}Cs) and {sup 21}Pb to study the filling velocity of salt marshes in Donana National Park (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Gasco, C. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Departamento de Medio Ambiente, Avda. Complutense 22, Madrid 28040 (Spain); Anton, M.P. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Departamento de Medio Ambiente, Avda. Complutense 22, Madrid 28040 (Spain)]. E-mail: maripaz.anton@ciemat.es; Pozuelo, M. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Departamento de Medio Ambiente, Avda. Complutense 22, Madrid 28040 (Spain); Clemente, L. [Consejo Superior de Investigaciones Cientificas, Instituto de Recursos Naturales y Agrobiologia, CSIC-IRNA, Departamento de Geoecologia, Avda. Reina Mercedes s/n, Sevilla 41012 (Spain); Rodriguez, A. [Universidad de Huelva, Departamento de Geodinamica y Paleontologia, Avda. de las Fuerzas Armadas s/n, Huelva 21071 (Spain); Yanez, C. [Consejo Superior de Investigaciones Cientificas, Instituto de Recursos Naturales y Agrobiologia, CSIC-IRNA, Departamento de Geoecologia, Avda. Reina Mercedes s/n, Sevilla 41012 (Spain); Gonzalez, A. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Departamento de Medio Ambiente, Avda. Complutense 22, Madrid 28040 (Spain); Meral, J. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Departamento de Medio Ambiente, Avda. Complutense 22, Madrid 28040 (Spain)

    2006-07-01

    Within an extensive multinational and multidisciplinary project carried out in Donana National Park (Spain) to investigate its preservation and regeneration, the filling velocity of the salt marshes has been evaluated through the calculation of their average sediment accumulation rates. {sup 239+24}Pu and {sup 137}Cs from weapons testing fallout and total {sup 21}Pb distribution profiles and inventories have been determined in some of the most characteristic zones of the park, namely, the ponds (or 'lucios') and the waterjets (or 'canos'). Plutonium inventories range from 16 to 101 Bq m{sup -2}, {sup 137}Cs values fluctuate between 514 and 3758 Bq m{sup -2} and unsupported {sup 21}Pb values comprise between 124 and 9398 Bq m{sup -2}. Average sedimentation rates range from 3 to 5 mm y{sup -1} (1952-2002). These data are higher than those obtained by carbon dating for the period 6500 AD-present, estimated as 1.5-2 mm y{sup -1}, suggesting an increase in the accumulation of sediments and the alteration of the park's hydrodynamics caused by the re-channeling of the major rivers feeding the salt marshes.

  9. Polysulfone and polyacrylate-based zwitterionic coatings for the prevention and easy removal of marine biofouling.

    Science.gov (United States)

    Hibbs, Michael R; Hernandez-Sanchez, Bernadette A; Daniels, Justin; Stafslien, Shane J

    2015-01-01

    A series of polysulfone and polyacrylate-based zwitterionic coatings were prepared on epoxy-primed aluminum substrata and characterized for their antifouling (AF) and fouling-release (FR) properties towards marine bacteria, microalgae and barnacles. The zwitterionic polymer coatings provided minimal resistance against bacterial biofilm retention and microalgal cell attachment, but facilitated good removal of attached microbial biomass by exposure to water-jet apparatus generated hydrodynamic shearing forces. Increasing the ion content of the coatings improved the AF properties, but required a stronger adhesive bond to the epoxy-primed aluminum substratum to prevent coating swelling and dissolution. Grafted poly(sulfobetaine) (gpSBMA), the most promising zwitterionic coating identified from microfouling evaluations, enabled the removal of four out of five barnacles reattached to its surface without incurring damage to their baseplates. This significant result indicated that gpSBMA relied predominately on its surface chemistry for its FR properties since it was very thin (~1-2 µm) relative to commercial coating standards (>200 µm).

  10. Manufacturing Process Developments for Regeneratively-Cooled Channel Wall Rocket Nozzles

    Science.gov (United States)

    Gradl, Paul; Brandsmeier, Will

    2016-01-01

    Regeneratively cooled channel wall nozzles incorporate a series of integral coolant channels to contain the coolant to maintain adequate wall temperatures and expand hot gas providing engine thrust and specific impulse. NASA has been evaluating manufacturing techniques targeting large scale channel wall nozzles to support affordability of current and future liquid rocket engine nozzles and thrust chamber assemblies. The development of these large scale manufacturing techniques focus on the liner formation, channel slotting with advanced abrasive water-jet milling techniques and closeout of the coolant channels to replace or augment other cost reduction techniques being evaluated for nozzles. NASA is developing a series of channel closeout techniques including large scale additive manufacturing laser deposition and explosively bonded closeouts. A series of subscale nozzles were completed evaluating these processes. Fabrication of mechanical test and metallography samples, in addition to subscale hardware has focused on Inconel 625, 300 series stainless, aluminum alloys as well as other candidate materials. Evaluations of these techniques are demonstrating potential for significant cost reductions for large scale nozzles and chambers. Hot fire testing is planned using these techniques in the future.

  11. Experimental and Numerical Study of the Influence of Substrate Surface Preparation on Adhesion Mechanisms of Aluminum Cold Spray Coatings on 300M Steel Substrates

    Science.gov (United States)

    Nastic, A.; Vijay, M.; Tieu, A.; Rahmati, S.; Jodoin, B.

    2017-07-01

    The effect of substrate surface topography on the creation of metallurgical bonds and mechanical anchoring points has been studied for the cold spray deposition of pure aluminum on 300M steel substrate material. The coatings adhesion strength showed a significant decrease from 31.0 ± 5.7 MPa on polished substrates to 6.9 ± 2.0 MPa for substrates with roughness of 2.2 ± 0.5 μm. Strengths in the vicinity of 45 MPa were reached for coatings deposited onto forced pulsed waterjet treated surfaces with roughnesses larger than 33.8 μm. Finite element analysis has confirmed the sole presence of mechanical anchoring in coating adhesion strength for all surface treatment except polished surfaces. Grit embedment has been shown to be non-detrimental to coating adhesion for the current deposited material combination. The particle deformation process during impacts has been studied through finite element analysis using the Preston-Tonks-Wallace (PTW) constitutive model. The obtained equivalent plastic strain (PEEQ), temperature, contact pressure and velocity vector were correlated to the particle ability to form metallurgical bonds. Favorable conditions for metallurgical bonding were found to be highest for particles deposited on polished substrates, as confirmed by fracture surface analysis.

  12. 高压水射流在发动机密封垫清理去除中的应用%The new application for High Pressure Water-jet(WJ) to remove and clean sealing plate on engine connecting surface

    Institute of Scientific and Technical Information of China (English)

    蔺焕章; 朱派龙; 周欣; 谢建正

    2001-01-01

    In this paper, the authors have carried out the high pressure water-jet (WJ) technology, which owns many advantages such as selective cutting ,cold cutting and powerful cleaning ability etc., to cope with this problem successfully, with flexible table designed and proper parameters chosen. On the basis of introduction to the forming principle, technical features and the equipment structure of WJ, and with the structure feature and materials of engine and sealing plate considered, several schedules are discussed, with adequate machining parameters and excellent results obtained, which will provide with new thoughts or approaches for similar cleaning jobs. It is proved that it is effective, flexible, safe, easy to handle and do no harm to the original machining quality or operator to use WJ to remove and clean the sealing plate on connecting surface of all kinds of engines instead of manual scraping.%在各种发动机的维修和翻修中,有大量的密封垫需去除更换。本文介绍具有诸多独特优势的高压水射流(WJ)来解决此问题。在介绍WJ形成原理、设备构成、射流结构和技术特点的基础上,结合发动机箱体、缸体材料组成、结构特征,给出了实施方案。以摩托车发动机缸体为例,设计了实用的工装,并试验了影响效率的诸多因素和规律,展示了试验效果。

  13. Rotating transient jet hitting force of the high-pressure jet manifold underwater net-washing machine%高压射流水下洗网机旋转的瞬态射流打击力研究

    Institute of Scientific and Technical Information of China (English)

    张小明; 郭根喜; 陶启友; 黄小华; 胡昱

    2011-01-01

    Calculated out the rotating transient jet angular velocity and hitting force of high-pressure water-jet manifold underwater net-washing machine,according to hydraulic dynamics. Analyzes demonstrated that the transient jet hitting force F diminished with the deflection angle α increasing,but increased with the pressure p,gyration radius R and the nozzle diameter d increasing; a reasonable choice of nozzle diameter d would primarily enhanced the role of the transient hitting force F to the stable working state ,while the increase of the gyration radius R had weak effect on the transient jet hitting force F. Oceania cleaning experiments showed that the apparatus rapidly reached the stable state and cleaned the nets well under the normal operating condition of the pump.%利用水力学得到歧管式高压射流水下洗网机旋转瞬态射流角速度公式和瞬态射流打击力公式.研究结果表明:洗网机旋转的瞬态射流打击力F随偏转角α增大而递减,但随射流压力P、洗网机旋转半径R和喷嘴孔径d增大而增大,合理选择喷嘴孔径d对瞬态射流打击力F迅速达到稳定状态的作用明显,而增大洗网机旋转半径R对瞬态射流打击力F的增强作用较弱.海上清洗实验表明,在工作泵正常工作条件下,洗网装置迅速达到工作状态,清洗网农效果良好.

  14. Research on and Design of a Self-Propelled Nozzle for the Tree-Type Drilling Technique in Underground Coal Mines

    Directory of Open Access Journals (Sweden)

    Yiyu Lu

    2015-12-01

    Full Text Available Due to the increasing depths of coal mines and the low permeability of some coal seams, conventional methods of gas drainage in underground mines are facing many problems. To improve gas extraction, a new technique using water jets to drill tree-type boreholes in coal seams is proposed. A self-propelled water-jet drilling nozzle was designed to drill these boreholes. The configuration of the self-propelled nozzle was optimized by conducting drilling experiments and self-propelling force measurements. Experimental results show that the optimal self-propelled nozzle has a forward orifice axial angle at 25°, a radial angle at 90°, a center distance of 1.5 mm, and backward pointing orifices with an axial angle of 25°. The self-propelling force generated by the jets of the nozzle with 30 MPa pump pressure can reach 29.8 N, enough to pull the hose and the nozzle forward without any external forces. The nozzle can drill at speeds up to 41.5 m/h with pump pressures at 30 MPa. The radial angles of the forward orifices improve the rock breaking performance of the nozzle and, with the correct angle, the rock breaking area of the orifices overlap to produce a connecting hole. The diameter of boreholes drilled by this nozzle can reach 35.2 mm. The nozzle design can be used as the basis for designing other self-propelled nozzles. The drilling experiments demonstrate the feasibility of using the tree-type drilling technique in underground mines.

  15. Optical stimulation of zebrafish hair cells expressing channelrhodopsin-2.

    Directory of Open Access Journals (Sweden)

    Bryan D Monesson-Olson

    Full Text Available Vertebrate hair cells are responsible for the high fidelity encoding of mechanical stimuli into trains of action potentials (spikes in afferent neurons. Here, we generated a transgenic zebrafish line expressing Channelrhodopsin-2 (ChR2 under the control of the hair-cell specific myo6b promoter, in order to examine the role of the mechanoelectrical transduction (MET channel in sensory encoding in afferent neurons. We performed in vivo recordings from afferent neurons of the zebrafish lateral line while activating hair cells with either mechanical stimuli from a waterjet or optical stimuli from flashes of ∼470-nm light. Comparison of the patterns of encoded spikes during 100-ms stimuli revealed no difference in mean first spike latency between the two modes of activation. However, there was a significant increase in the variability of first spike latency during optical stimulation as well as an increase in the mean number of spikes per stimulus. Next, we compared encoding of spikes during hair-cell stimulation at 10, 20, and 40-Hz. Consistent with the increased variability of first spike latency, we saw a significant decrease in the vector strength of phase-locked spiking during optical stimulation. These in vivo results support a physiological role for the MET channel in the high fidelity of first spike latency seen during encoding of mechanical sensory stimuli. Finally, we examined whether remote activation of hair cells via ChR2 activation was sufficient to elicit escape responses in free-swimming larvae. In transgenic larvae, 100-ms flashes of ∼470-nm light resulted in escape responses that occurred concomitantly with field recordings indicating Mauthner cell activity. Altogether, the myo6b:ChR2 transgenic line provides a platform to investigate hair-cell function and sensory encoding, hair-cell sensory input to the Mauthner cell, and the ability to remotely evoke behavior in free-swimming zebrafish.

  16. A PRIVILEGED CITY ESKISEHiR IN TERMS OF THE PARK AND GARDEN CERAMICS AND A CONVERSATION WITH PROF. BiLGEHAN UZUNER

    Directory of Open Access Journals (Sweden)

    Burak Yıldırım

    2014-12-01

    Full Text Available Parks and gardens are always the important places for us. During our history, they have creatured the culturel communication environments, universalizing the artistic and aesthetic consciousness, enabling to develop the protecting awareness of the ecological balance, helping people getting rid from crowded cities and distressing mood and have enabled to stay cheek by jowl with the nature in this places, the designs entwined with nature and artistic works are now a days very important. We are able to see the use of the common and advanced form of parks and gardens from 1960 to the present and their examples made for various purposes in many countries of the world. Today, in our country and around the world, a lot of ceramic artists have been still producing realistic, stylizedor abstract sculptures, monuments, benches, wallboards, birdhouses, pools, fountains and waterjets on behalf of park-garden and these ceramics support contemporary architecture, interiordesign, landscape architecture, urban and regional planning areas and these are functional and decorative ceramics. In our country, compared to cities in other European countries, the production of the ceramics such as parks-gardens are insufficient except for big cities such as İstanbul, İzmir, Ankara. But in this context Eskişehir has a privileged place. Eskişehir is a city of art. Because the city has ceramic works, having been produced in the International Terra Cotta Symposium since 2001 and the city has been decorated these ceramic Works in many public gardens and parking area. This symposium has been arranged by Eskişehir Anadolu University Faculty of Fine Arts Professor Bilgehan Uzuner.

  17. ENHANCED PRACTICAL PHOTOSYNTHETIC CO2 MITIGATION

    Energy Technology Data Exchange (ETDEWEB)

    Dr. David J. Bayless; Dr. Morgan Vis; Dr. Gregory Kremer; Dr. Michael Prudich; Dr. Keith Cooksey; Dr. Jeff Muhs

    2001-04-16

    This quarterly report documents significant achievements in the Enhanced Practical Photosynthetic CO{sub 2} Mitigation project during the period from 1/03/2001 through 4/02/2001. Many of the activities and accomplishments are continuations of work initiated and reported in last quarter's status report. Major activities and accomplishments for this quarter include: Three sites in Yellowstone National Park have been identified that may contain suitable organisms for use in a bioreactor; Full-scale culturing of one thermophilic organism from Yellowstone has progressed to the point that there is a sufficient quantity to test this organism in the model-scale bioreactor; The effects of the additive monoethanolamine on the growth of one thermophilic organism from Yellowstone has been tested; Testing of growth surface adhesion and properties is continuing; Construction of a larger model-scale bioreactor to improve and expand testing capabilities is completed and the facility is undergoing proof tests; Model-scale bioreactor tests examining the effects of CO{sub 2} concentration levels and lighting levels on organism growth rates are continuing; Alternative fiber optic based deep-penetration light delivery systems for use in the pilot-scale bioreactor have been designed, constructed and tested; An existing slug flow reactor system has been modified for use in this project, and a proof-of-concept test plan has been developed for the slug flow reactor; Research and testing of water-jet harvesting techniques is continuing, and a harvesting system has been designed for use in the model-scale bioreactor; and The investigation of comparative digital image analysis as a means for determining the ''density'' of algae on a growth surface is continuing Plans for next quarter's work and an update on the project's web page are included in the conclusions.

  18. Thermodynamic analysis of resources used in manufacturing processes.

    Science.gov (United States)

    Gutowski, Timothy G; Branham, Matthew S; Dahmus, Jeffrey B; Jones, Alissa J; Thiriez, Alexandre

    2009-03-01

    In this study we use a thermodynamic framework to characterize the material and energy resources used in manufacturing processes. The analysis and data span a wide range of processes from "conventional" processes such as machining, casting, and injection molding, to the so-called "advanced machining" processes such as electrical discharge machining and abrasive waterjet machining, and to the vapor-phase processes used in semiconductor and nanomaterials fabrication. In all, 20 processes are analyzed. The results show that the intensity of materials and energy used per unit of mass of material processed (measured either as specific energy or exergy) has increased by at least 6 orders of magnitude over the past several decades. The increase of material/energy intensity use has been primarily a consequence of the introduction of new manufacturing processes, rather than changes in traditional technologies. This phenomenon has been driven by the desire for precise small-scale devices and product features and enabled by stable and declining material and energy prices over this period. We illustrate the relevance of thermodynamics (including exergy analysis) for all processes in spite of the fact that long-lasting focus in manufacturing has been on product quality--not necessarily energy/material conversion efficiency. We promote the use of thermodynamics tools for analysis of manufacturing processes within the context of rapidly increasing relevance of sustainable human enterprises. We confirm that exergy analysis can be used to identify where resources are lost in these processes, which is the first step in proposing and/or redesigning new more efficient processes.

  19. Next Generation Lightweight Mirror Modeling Software

    Science.gov (United States)

    Arnold, William R., Sr.; Fitzgerald, Mathew; Rosa, Rubin Jaca; Stahl, H. Philip

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models easier.

  20. Next-Generation Lightweight Mirror Modeling Software

    Science.gov (United States)

    Arnold, William R., Sr.; Fitzgerald, Mathew; Rosa, Rubin Jaca; Stahl, Phil

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models possible

  1. Cytokine-Rich Adipose Tissue Extract Production from Water-Assisted Lipoaspirate: Methodology for Clinical Use

    Science.gov (United States)

    Lopez, Jenny; Huttala, Outi; Sarkanen, Jertta-Riina; Kaartinen, Ilkka; Kuokkanen, Hannu; Ylikomi, Timo

    2016-01-01

    Abstract Proper functioning wound healing strategies are sparse. Adequate vascular formation to the injured area, as well as replacement of the volume loss, is fundamental in soft tissue repair. Tissue engineering strategies have been proposed for the treatment of these injury sites. Novel cell-free substance, human adipose tissue extract (ATE), has been previously shown to induce in vitro angiogenesis and adipogenesis and in vivo soft tissue formation. This study reports the translation of ATE preparation from laboratory to the operating room (OR). ATE samples for this study were derived from adipose tissue obtained with the water-jet assisted liposuction technique from 27 healthy patients. The variables studied included incubation time (15, 30, and 45 min), temperature (room temperature vs. 37°C), and filter type to determine the optimal method yielding the most consistent total protein content, as well as consistent and high expression of adipose-derived growth factors and cytokines, including: vascular endothelial growth factor, basic fibroblast growth factor, interleukin-6, adiponectin, leptin, and insulin-like growth factor. Following the optimization, samples were produced in the OR and tested for their sterility. No significant differences were observed when comparing extract incubation time points or incubation temperature. Nonetheless, when studying the different filter types used, a syringe filter with PES membrane with larger filter area showed significantly higher protein concentration (p ≤ 0.018). When studying the different growth factor concentrations, ELISA results showed less variation in cytokine concentrations in the OR samples with the optimized protocol. All of the OR samples were tested sterile. The devised protocol is an easy and reproducible OR-ready method for ATE generation. As an attractive source of growth factors, ATE is a promising alternative in the vast field of tissue engineering. Its clinical applications include volume

  2. Erosion and corrosion resistance of laser cladded AISI 420 stainless steel reinforced with VC

    Science.gov (United States)

    Zhang, Zhe; Yu, Ting; Kovacevic, Radovan

    2017-07-01

    Metal Matrix Composites (MMC) fabricated by the laser cladding process have been widely applied as protective coatings in industries to improve the wear, erosion, and corrosion resistance of components and prolong their service life. In this study, the AISI 420/VC metal matrix composites with different weight percentage (0 wt.%-40 wt.%) of Vanadium Carbide (VC) were fabricated on a mild steel A36 by a high power direct diode laser. An induction heater was used to preheat the substrate in order to avoid cracks during the cladding process. The effect of carbide content on the microstructure, elements distribution, phases, and microhardness was investigated in detail. The erosion resistance of the coatings was tested by using the abrasive waterjet (AWJ) cutting machine. The corrosion resistance of the coatings was studied utilizing potentiodynamic polarization. The results showed that the surface roughness and crack susceptibility of the laser cladded layer were increased with the increase in VC fraction. The volume fraction of the precipitated carbides was increased with the increase in the VC content. The phases of the coating without VC consisted of martensite and austenite. New phases such as precipitated VC, V8C7, M7C3, and M23C6 were formed when the primary VC was added. The microhardness of the clads was increased with the increase in VC. The erosion resistance of the cladded layer was improved after the introduction of VC. The erosion resistance was increased with the increase in the VC content. No obvious improvement of erosion resistance was observed when the VC fraction was above 30 wt.%. The corrosion resistance of the clads was decreased with the increase in the VC content, demonstrating the negative effect of VC on the corrosion resistance of AISI 420 stainless steel

  3. 快速复合融除冰装置的研究%Research of Rapid Compound Deicing Equipment

    Institute of Scientific and Technical Information of China (English)

    朱自成; 张学军; 徐肖攀; 储伟俊; 李超新

    2014-01-01

    如何保证冰雪天气条件下交通顺畅、行车安全,提高道路通行能力和运营效益、减少和避免交通事故发生是当今面临的一大难题。为此,在分析现有不同除冰方法的基础上,提出一种融合热力-水射流切割融除冰与机械铣削除冰的复合除冰方法。介绍了热力快速复合融除冰装置和机械铣削除冰装置的结构组成、工作原理,设计了复合融除冰装置,并进行了相关试验。结果表明:该装置可以很好地完成融除冰任务,满足设计需求。%Determining how to strikingly reduce the accident rate on roads,ensure traffic flow and safety in the icy weather,and improve the capacity and efficiency of transportation in snow weather has become a tough issue nowadays.A new method was presented in which thermal water-jet cutting was combined with mechanical-milling deicing technology,basing on current different deicing meth-ods.Then the structure and working principle of this device were introduced,together with the practicality design.The experimental results indicate that this device can perform well in deicing work,and satisfy the design requirements.

  4. [Evaluation of potential risks of abrasive water jet osteotomy in-vivo].

    Science.gov (United States)

    Kuhlmann, C; Pude, F; Bishup, C; Krömer, S; Kirsch, L; Andreae, A; Wacker, K; Schmolke, S

    2005-10-01

    Since the 80's the water jet scalpel is an established tool in some surgical fields. It is used in particular in visceral surgery for preparation of parenchymatous organs. By the addition of biocompatible abrasives, this technique is able to effectively machine hard biological tissues. Free defined cutting geometries can be realised in a non contact process. Therewith this method has crucial advantages compared to conventional osteotomy techniques and gives new impulses to the development in endoprosthetics and correction osteotomies of hollow bones. In the presented work the new developed abrasive water injection jet (AWIJ) was used the first time for in-vivo osteotomies. Aim of this study was the detection of potential thrombembolic effects and wash in effects of the cutting fluid. Hollow bones of the fore and hind leg of 20 house pigs were treated with the new cutting technique. Intraoperative documentation of relevant vital parameters was performed by a multi monitoring system. Thrombembolic effects during the osteotomy were detected by transthoracic Doppler ultrasonography and transesophagale echocardiography. The hollow bones were prepared in consideration of the vascularisation's protection especially in respect to the venous flow. Thrombembolic effects with temporary haemodynamic respectively respiratory consequences could be detected exclusively by using the so called "3-component jet", which consists of 90 vol % of air. The usage of an abrasive suspension enables the airfree dosing of dry soluable abrasives. Thrombembolic effects could not be monitored in this case. Intramedullary fluid in-wash effects as well as resulting electrolytic disorders could not be proven. For abrasive waterjet osteotomies with 3 component jet a relevant risk of thrombembolic effects could be shown. This knowledge has also to be considered for abdominal and neurosurgical applications in the future. Due to the usage of an abrasive suspension this risk can fully be avoided.

  5. 大厚度材料磨料水射流切割工艺及关键技术%Abrasive Water Jet Cutting Process and Key Technology of Big-thickness Materials

    Institute of Scientific and Technical Information of China (English)

    李连荣; 王晓燕; 许栋刚

    2012-01-01

    water-jet cutting process with its unique cold and soft processing characteristics, and more unique advantages compared to other cutting process according to all kinds of thermal and hard brittle materials has good prospects for future development. But because of its own flexible jet characteristics, especially in cutting big thickness materials, it exists the quality insufficient obvious such as slope, corrugated, cross section lag, cut back sewing. That becomes the marketing bottlenecks restricted technology. In this paper, from the abrasive water jet cutting process principle mechanism and technology advantages, based on the points out its defects and cutting process effect factors affecting process, the specific key technology was proposed. It has positive practical significance to expand the application fields.%磨料水射流切割工艺以其独特的“冷、软”加工特性,与其他切割工艺相比,对各类热敏、硬脆等难加工材料的切割更有独特优势,具有良好的发展前景.但因射流自身的“柔性”特征,尤其在切割大厚度材料时存在断面明显坡度、波纹、滞后、切缝、回击等质量不足,成为制约该技术应用市场推广的瓶颈.本文从磨料水射流切割工艺原理和工艺优势出发,在指出其工艺缺陷和切割效果工艺影响因素的基础上,提出针对性的关键技术,对拓展该技术的应用领域具有积极的现实意义.

  6. Use of Multibeam and Dual-Beam Sonar Systems to Observe Cavitating Flow Produced by Ferryboats: In a Marine Renewable Energy Perspective

    Directory of Open Access Journals (Sweden)

    Francisco Francisco

    2017-07-01

    Full Text Available With the prospect to deploy hydrokinetic energy converters in areas with heavy boat traffic, a study was conducted to observe and assess the depth range of cavitating flow produced by ferryboats in narrow channels. This study was conducted in the vicinity of Finnhamn Island in Stockholm Archipelago. The objectives of the survey were to assess whether the sonar systems were able to observe and measure the depth of what can be cavitating flow (in a form of convected cloud cavitation produced by one specific type of ferryboats frequently operating in that route, as well as investigate if the cavitating flow within the wake would propagate deep enough to disturb the water column underneath the surface. A multibeam and a dual-beam sonar systems were used as measurement instruments. The hypothesis was that strong and deep wake can disturb the optimal operation of a hydrokinetic energy converter, therefore causing damages to its rotors and hydrofoils. The results showed that both sonar system could detect cavitating flows including its strength, part of the geometrical shape and propagation depth. Moreover, the boat with a propeller thruster produced cavitating flow with an intense core reaching 4 m of depth while lasting approximately 90 s. The ferry with waterjet thruster produced a less intense cavitating flow; the core reached depths of approximately 6 m, and lasted about 90 s. From this study, it was concluded that multibeam and dual-beam sonar systems with operating frequencies higher than 200 kHz were able to detect cavitating flows in real conditions, as long as they are properly deployed and the data properly analyzed.

  7. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy.

    Science.gov (United States)

    Miaja-Avila, L; O'Neil, G C; Uhlig, J; Cromer, C L; Dowell, M L; Jimenez, R; Hoover, A S; Silverman, K L; Ullom, J N

    2015-03-01

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼10(6) photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >10(7) laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  8. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    Directory of Open Access Journals (Sweden)

    L. Miaja-Avila

    2015-03-01

    Full Text Available We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  9. [Transurethral en bloc resection of non-muscle invasive bladder cancer. What is the state of the art?].

    Science.gov (United States)

    Kramer, M W; Wolters, M; Abdelkawi, I F; Merseburger, A S; Nagele, U; Gross, A; Bach, T; Kuczyk, M A; Herrmann, T R W

    2012-06-01

    Bladder cancer of the urothelium is the second most common malignancy among urological tumors. In view of a worldwide aging population and the fact that increased incidence rates are associated with higher age, new socioeconomic challenges will appear. Even nowadays the treatment of bladder cancer bears the highest lifetime treatment costs per patient among all forms of cancer. In conjunction with higher comorbidity rates among older patients urologists are facing new challenges in the treatment and care of patients with bladder cancer. The standard treatment for non-muscle invasive bladder cancer (NMIBC) is monopolar transurethral resection using resection loops (TURB). Based on experience in the surgical treatment of benign prostatic hyperplasia, different concepts of en bloc resection of bladder tumors using alternative energy resources (e.g. holmium laser, thulium laser and the water-jet HybridKnife) have been developed. Goals of new treatment modalities are reduction of perioperative and postoperative comorbidities, better pathological work-up of the specimens and increased recurrence-free survival. Postulated advantages using laser devices are a more precise cutting line as well as better hemostasis. The evidential value of this review is limited due to the lack of randomized, prospective studies. However, there is a tendency towards a limitation of perioperative and postoperative morbidities as well as higher chance of well-preserved tissues for better pathohistological evaluation using en bloc resection methods. More studies with long-term follow-up periods and better randomization are needed to clarify whether en bloc strategies provide better long-term oncological survival.

  10. Feeding behaviour of free-ranging walruses with notes on apparent dextrality of flipper use

    Directory of Open Access Journals (Sweden)

    Ehlme Göran

    2003-10-01

    Full Text Available Abstract Background Direct observations of underwater behaviour of free-living marine mammals are rare. This is particularly true for large and potentially dangerous species such as the walrus (Odobenus rosmarus. Walruses are highly specialised predators on benthic invertebrates – especially bivalves. The unique feeding niche of walruses has led to speculations as to their underwater foraging behaviour. Based on observations of walruses in captivity and signs of predation left on the sea floor by free-living walruses, various types of feeding behaviour have been suggested in the literature. In this study, however, the underwater feeding behaviour of wild adult male Atlantic walruses (O. r. rosmarus is documented for the first time in their natural habitat by scuba-divers. The video recordings indicated a predisposition for use of the right front flipper during feeding. This tendency towards dextrality was explored further by examining a museum collection of extremities of walrus skeletons. Results During July and August 2001, twelve video-recordings of foraging adult male walruses were made in Young Sound (74°18 N; 20°15 V, Northeast Greenland. The recordings did not allow for differentiation among animals, however based on notes by the photographer at least five different individuals were involved. The walruses showed four different foraging behaviours; removing sediment by beating the right flipper, removing sediment by beating the left flipper, removing sediment by use of a water-jet from the mouth and rooting through sediment with the muzzle. There was a significant preference for using right flipper over left flipper during foraging. Measurements of the dimensions of forelimbs from 23 walrus skeletons revealed that the length of the right scapula, humerus, and ulna was significantly greater than that of the left, supporting our field observations of walruses showing a tendency of dextrality in flipper use. Conclusion We suggest that the

  11. An ultrasound biomicroscopic and water jet ultrasound indentation method for detecting the degenerative changes of articular cartilage in a rabbit model of progressive osteoarthritis.

    Science.gov (United States)

    Wang, Yuexiang; Huang, Yan-Ping; Liu, Aijun; Wan, Wenbo; Zheng, Yong-Ping

    2014-06-01

    It is important to assess the early degeneration of articular cartilage associated with osteoarthritis (OA) for early intervention and treatment planning. Previously, we have developed a high frequency ultrasound and water jet indentation method for the morphologic, acoustic and mechanical assessment of articular cartilage, using the enzymatic digestion as a model of osteoarthritic degeneration. No naturally degenerated articular cartilage has been tested with the developed method. In this study, we aimed to determine the usefulness of the developed method for detecting the natural degeneration of articular cartilage in a standard surgical model of OA in rabbits. Forty adult New Zealand white female rabbits were used in this study, which included 30 experimental rabbits undergoing the right anterior cruciate ligament transection surgery and 10 control rabbits. At the 3rd, 6th, and 9th week post-surgery, 10 experimental rabbits were sacrificed, respectively, for assessment of the knee cartilage quality. The cartilage at the medial and lateral femoral condyles and tibial plateaus (four points) was measured by the high frequency ultrasound biomicroscopy, the water jet ultrasound indentation and a contact mechanical indentation test before a histopathologic analysis for grading of degeneration severity. Measured parameters were compared among different groups classified either by post-surgery time or by histopathologic grade. The results showed a general trend of increase for ultrasound roughness index and a general trend of decrease for integrated reflection coefficient, stiffness coefficient from water-jet indentation and Young's modulus (E) from the mechanical indentation with the increase of post-surgery time. Comparisons among groups with different histopathologic grades showed similar trend with the increase of degeneration severity. The water jet ultrasound indentation method was demonstrated to be an effective method to measure the mechanical properties of the

  12. Deployment of a Long-Term Broadband Seafloor Observatory in Monterey Bay

    Science.gov (United States)

    McGill, P.; Neuhauser, D.; Stakes, D.; Romanowicz, B.; Ramirez, T.; Uhrhammer, R.

    2002-12-01

    MOBB (Monterey bay Ocean floor Broad Band project) is a collaborative project between the Monterey Bay Aquarium Research Institute (MBARI) and the Berkeley Seismological Laboratory (BSL). Its goal is to install and operate a permanent seafloor broadband seismic station as a first step towards extending the on-shore broadband seismic network in northern California to the seaside of the North-America/Pacific plate boundary, providing better azimuthal coverage for regional earthquake and structure studies. The successful MOBB deployment took place 40km off shore at a water depth of 1000m during three dives on April 9-11, 2002. The seismometer was buried in a 60-cm deep caisson, which was later back filled with glass beads to stabilize the instrument. New tools, including a high-pressure water-jet excavator, were developed for the ROV Ventana to accomplish these tasks. The ocean-bottom MOBB station currently comprises a three-component seismometer package, a current-meter, and a recording and battery package. Data recovery dives, during which the recording and battery package will be exchanged, are planned every three months for the next three years. A differential pressure gauge (DPG) (Cox et al., 1984) will be deployed as part of the recording package during the next data recovery dive in September 2002. The station is currently recording data autonomously. Eventually, it will be linked to the planned (and recently funded) MARS (Monterey Accelerated Research System; rl {http://www.mbari.org/mars/}) cable and provide real-time, continuous seismic data to be merged with the rest of the northern California real-time seismic system. The data are archived at the NCEDC for on-line availability, as part of the Berkeley Digital Seismic Network (BDSN). This project follows the 1997 MOISE experiment, in which a three-component broadband system was deployed for a period of three months, 40km off shore in Monterey Bay. MOISE was a cooperative program sponsored by MBARI, UC

  13. Descriptive models for single-jet sluicing of sludge waste

    Energy Technology Data Exchange (ETDEWEB)

    Erian, F.F.; Mahoney, L.A.; Terrones, G.

    1997-12-01

    Mobilization of sludge waste stored in underground storage tanks can be achieved safely and reliably by sluicing. In the project discussed in this report, the waste in Hanford single-shell Tank 241-C-106 will be mobilized by sluicing, retrieved by a slurry retrieval pump, and transferred via an 1800-ft slurry pipeline to Tank 241-AY-102. A sluicing strategy must be developed that ensures efficient use of the deployed configuration of the sluicing system: the nozzle(s) and the retrieval pump(s). Given a sluicing system configuration in a particular tank, it is desirable to prescribe the sequential locations at which the sludge will be mobilized and retrieved and the rate at which these mobilization and retrieval processes take place. In addition, it is necessary to know whether the retrieved waste slurry meets the requirements for cross-site slurry transport. Some of the physical phenomena that take place during mobilization and retrieval and certain aspects of the sluicing process are described in this report. First, a mathematical model gives (1) an idealized geometrical representation of where, within the confines of a storage tank containing a certain amount of settled waste, sludge can be removed and mobilized; and (2) a quantitative measure of the amount of sludge that can be removed during a sluicing campaign. A model describing an idealized water jet issuing from a circular nozzle located at a given height above a flat surface is also presented in this report. This dynamic water-jet model provides the basis for improving the geometrical sluicing model presented next. In this model the authors assume that the water jet follows a straight trajectory toward a target point on a flat surface. However, the water jet does not follow a straight line in the actual tank, and using the true trajectory will allow a more accurate estimate of the amount of disturbed material. Also, the authors hope that developing accurate force and pressure fields will lead to a better

  14. 汶川大地震液化的特点及带来的新问题%Features and new aspects of liquefaction in the Wenchuan Earthquake

    Institute of Scientific and Technical Information of China (English)

    袁晓铭; 曹振中

    2011-01-01

    The scientific investigation on liquefaction induced by Wenchuan earthquake is outlined and presented herein, and new aspects concerning on liquefaction are analyzed and proposed. The results show: ( 1 ) the liquefaction and associated damage in the event are dramatic, involving widest areas and abundant macrophenomena; (2)the features of liquefaction are high water-jet, short duration and small quantity of ejected materials, but the categories of ejected sand are various; (3) five remarkable features are gravel liquefaction, liquefaction in seismic intensity Ⅵ regions, deep soil liquefaction, liquefaction exacerbation effect on structures and most liquefaction with cracks; (4) evaluation methods of gravel soil, mechanism and predicting methods of cracks caused by liquefaction,mechanism and predicting methods of liquefaction in seismic intensity Ⅵ and deep soil liquefaction, conditions of liquefaction exacerbation effect and energy absorption effect and liquefaction detection techniques are also new aspects. Therefore, it is completely necessary to develop new monitoring and measurement technologies and establish geotechnical earthquake engineering in-situ testing labs.%总结汶川8.0级大地震液化及其震害科学考察结果,分析此次地震液化带来的新问题.结果表明,汶川大地震中液化及其震害现象显著,是建国以来液化涉及区域最广、液化宏观现象最为丰富的一次;本次地震液化宏观现象特点为喷水高、持时短、喷砂量小但喷砂类型十分丰富;砂砾土液化、Ⅵ度区内场地液化、深层土液化、无液化减震以及液化普遍伴随地裂缝是此次地震液化5个突出特征;砂砾土液化判别技术、液化引起地表裂缝机理和预测方法、Ⅵ度区内场地液化与深层土的液化机理和预测方法、液化加减震发生条件、场地液化现场判定与识别技术等是新的课题.为解决上述问题,应优先发展岩土地震工程观测技术

  15. Diseño de un sistema de generación de chorro de agua de flujo laminar iluminado//Designing a system to generate water jet illuminated laminar flow

    Directory of Open Access Journals (Sweden)

    Néstor A. Ulloa-Auqui

    2015-09-01

    Full Text Available Se diseñó y fabricó exitosamente un Sistema de Generación de Chorro de Agua de Flujo Laminar Iluminado, el mismo tiene como finalidad desarrollar destrezas y capacidades en el laboratorio de fluidos cuando se realicen prácticas de variación de caudal para obtener diferentes alturas, alcances y observar como viajan las partículas de agua en un flujo laminar, fenómeno que se produce gracias a la iluminación de todo el chorro con la tecnología de la fibra óptica y un potenciador led RGB.  Los resultados obtenidos permiten realizar proyectos en el área de ornamentación que pueden ser utilizados de manera creativa en parques, hoteles, piscinas y piletas.  El estudio inicia con la determinación de las ecuaciones de cantidad de movimiento, balance de energía y movimiento parabólico que sirvieron para el cálculo hidráulico y selección de la bomba de caudal y boquilla del dispositivo. Palabras clave: flujo laminar, chorro de agua, fibra óptica, boquilla._____________________________________________________________________________AbstractA system to generate water jet illuminated laminar flow was successfully designed and fabricated, the same aims to develop skills and capabilities in the laboratory practices fluids when flow variation for different heights and ranges are made and watch the water particles traveling in laminar flow, phenomenon which occurs by lighting the whole jet technology with fiber optics and a RGB led enhancer.  The results obtained allow perform projects in the area of ornamentation, the same that can be used creatively in parks, hotels, swimming pools and fountains.  The study begins with the determination of the equations of momentum, energy balance and parabolic movement that served to the hydraulic calculation and selection of the pump flow and nozzle device. Key words: flow, laminar, waterjet, optical fiber, nozzle.

  16. Chapter L: U.S. Industrial Garnet

    Science.gov (United States)

    Evans, James G.; Moyle, Phillip R.

    2006-01-01

    The United States presently consumes about 16 percent of global production of industrial garnet for use in abrasive airblasting, abrasive coatings, filtration media, waterjet cutting, and grinding. As of 2005, domestic garnet production has decreased from a high of 74,000 t in 1998, and imports have increased to the extent that as much as 60 percent of the garnet used in the United States in 2003 was imported, mainly from India, China, and Australia; Canada joined the list of suppliers in 2005. The principal type of garnet used is almandite (almandine), because of its specific gravity and hardness; andradite is also extensively used, although it is not as hard or dense as almandite. Most industrial-grade garnet is obtained from gneiss, amphibolite, schist, skarn, and igneous rocks and from alluvium derived from weathering and erosion of these rocks. Garnet mines and occurrences are located in 21 States, but the only presently active (2006) mines are in northern Idaho (garnet placers; one mine), southeastern Montana (garnet placers; one mine), and eastern New York (unweathered bedrock; two mines). In Idaho, garnet is mined from Tertiary and (or) Quaternary sedimentary deposits adjacent to garnetiferous metapelites that are correlated with the Wallace Formation of the Proterozoic Belt Supergroup. In New York, garnet is mined from crystalline rocks of the Adirondack Mountains that are part of the Proterozoic Grenville province, and from the southern Taconic Range that is part of the northern Appalachian Mountains. In Montana, sources of garnet in placers include amphibolite, mica schist, and gneiss of Archean age and younger granite. Two mines that were active in the recent past in southwestern Montana produced garnet from gold dredge tailings and saprolite. In this report, we review the history of garnet mining and production and describe some garnet occurrences in most of the Eastern States along the Appalachian Mountains and in some of the Western States where

  17. Development of a patient-specific two-compartment anthropomorphic breast phantom

    Science.gov (United States)

    Prionas, Nicolas D.; Burkett, George W.; McKenney, Sarah E.; Chen, Lin; Stern, Robin L.; Boone, John M.

    2012-07-01

    The purpose of this paper is to develop a technique for the construction of a two-compartment anthropomorphic breast phantom specific to an individual patient's pendant breast anatomy. Three-dimensional breast images were acquired on a prototype dedicated breast computed tomography (bCT) scanner as part of an ongoing IRB-approved clinical trial of bCT. The images from the breast of a patient were segmented into adipose and glandular tissue regions and divided into 1.59 mm thick breast sections to correspond to the thickness of polyethylene stock. A computer-controlled water-jet cutting machine was used to cut the outer breast edge and the internal regions corresponding to glandular tissue from the polyethylene. The stack of polyethylene breast segments was encased in a thermoplastic ‘skin’ and filled with water. Water-filled spaces modeled glandular tissue structures and the surrounding polyethylene modeled the adipose tissue compartment. Utility of the phantom was demonstrated by inserting 200 µm microcalcifications as well as by measuring point dose deposition during bCT scanning. Affine registration of the original patient images with bCT images of the phantom showed similar tissue distribution. Linear profiles through the registered images demonstrated a mean coefficient of determination (r2) between grayscale profiles of 0.881. The exponent of the power law describing the anatomical noise power spectrum was identical in the coronal images of the patient's breast and the phantom. Microcalcifications were visualized in the phantom at bCT scanning. The real-time air kerma rate was measured during bCT scanning and fluctuated with breast anatomy. On average, point dose deposition was 7.1% greater than the mean glandular dose. A technique to generate a two-compartment anthropomorphic breast phantom from bCT images has been demonstrated. The phantom is the first, to our knowledge, to accurately model the uncompressed pendant breast and the glandular tissue

  18. Selective tissue elevation by pressure injection (STEP) facilitates endoscopic mucosal resection (EMR).

    Science.gov (United States)

    Kähler, Georg F B A; Sold, Moritz S; Post, Stefan; Fischer, Klaus; Enderle, Markus D

    2007-01-01

    Endoscopic mucosal resection and endoscopic submucosal dissection have become more common in treatment of flat superficial tumors of the gastrointestinal tract. Submucosal injection is used to try to avoid complications and improve the technical feasibility of the procedure. However, the method has its limitations, particularly when treating extensive flat tumors in the colon. The water-jet dissector has already demonstrated its capacity for selective cutting with the dissection of parenchymatous. This chapter addresses a new indication, transmucosal mucosal elevation, together with first clinical results. After carrying out animal experiments into the physical properties using animal preparations and freshly resected human specimens from operations, our work group investigated and compared the applicability of the procedure using different carrier fluids. Six test substances-hydroxyethyl starch (HES), Gelafusal, Infukoll, Glucose 50 und isotonic saline solution-were injected into six anesthetized pigs; the height of the submucosal fluid cushion created by the injection was measured endosonographically over a period of 45 minutes. Endoscopic mucosal resection was subsequently carried out, and the resected specimen together with the area it was taken from were assessed histologically. Using commercially available NaCl cartridges, applied by the way of endocapillaries, 18 lesions were elevated in a series of 12 patients and subsequently resected endoscopically. All investigated substances could be applied without difficulty using the Helix HydroJet (Erbe Elektromedizin GmbH, Waldhörnle-Str., Tübingen, Germany). The plasma expanders (HES and Gelafundin 4%, B. Braun Melsungen AG, Melsungen, Germany) produced longer lasting fluid cushions than the isotonic solutions. Mucosal resections could be carried out in all cases with all of the solutions. Histological investigation confirmed the selective nature of the fluid accumulation in the submucosal tissue, which spared

  19. 村镇供水中臭氧消毒副产物溴酸盐生成规律研究%Study on formation law of byproduct——bromate during ozone disinfection for rural drinking water supply

    Institute of Scientific and Technical Information of China (English)

    贾燕南; 宋卫坤; 李晓琴; 胡孟; 刘文朝

    2013-01-01

    结合村镇供水特点,本文采取三种投加方式对9省63份作为饮用水水源的地下水水样进行臭氧投加试验,考察了不同地区的水样消毒后生成溴酸盐浓度水平的差异,研究了臭氧投加量、投加方式对溴酸盐生成浓度的影响.结果表明:原水溴离子浓度越低,pH值越低,投加臭氧后生成的溴酸盐量也较小;溴酸盐生成量与臭氧投加量在一定范围内呈线性正相关关系.同一投加量下,三种臭氧投加方式对应的溴酸盐生成量由小到大依次为:投加高浓度臭氧水、水射器投加、直接通入臭氧气体.%In accordance with the characteristics of rural drinking water supply, the ozone adding experiment on the groundwater samples from 63 water sources for the rural drinking water in 9 provinces is made with three ozone dosing methods, and then the difference among the levels of bromate concentrations formed after the disinfections of the water samples from various areas is investigated and the impacts from both the ozone dosing and the dosing method on the bromate forming concentration are studied.The result shows that the less the bromonium ion concentration of the raw water is, the lower the pH value is to be, and then the less content of the bromate formed after ozone adding is to be as well, while the bromate formation shows linear positive correlation with the ozone dosage with a certain range.Under an identical dosing, the bromate formations corresponded to the three o-zone dosing methods, i.e.adding high concentration ozone water, adding by water-jet, direct adding of ozone gas, vary in an order from less to large.

  20. On the impacts of phytoplankton-derived organic matter on the properties of the primary marine aerosol – Part 1: Source fluxes

    Directory of Open Access Journals (Sweden)

    E. Fuentes

    2010-10-01

    Full Text Available The effect of biogenic dissolved and colloidal organic matter on the production of submicron primary sea-spray aerosol was investigated via the simulation of bubble bursting in seawater enriched with phytoplankton-released organics.

    Seawater samples collected along a transect off the West African coast during the RHaMBLe cruise (RRS Discovery cruise D319, conducted as part of the SOLAS UK program, were analysed in order to identify the dominant oceanic algal species in a region of high biological activity. Cultures of microalgal strains representative of the species found in the collected seawater were grown in order to produce natural bioexudate. Colloidal plus dissolved organic fraction in this material remaining after <0.2 μm filtration was employed to prepare organic-enriched seawater proxies for the laboratory production of marine aerosol using a plunging-waterjet system as an aerosol generator. Submicron size distributions of aerosols generated from different organic monolayers and seawater proxies enriched with biogenic exudate were measured and compared with blanks performed with artificial seawater devoid of marine organics. A shift of the aerosol submicron size distribution toward smaller sizes and an increase in the production of particles with dry diameter (Dp0<100 nm was repeatedly observed with increasing amounts of diatomaceous bioexudate in the seawater proxies used for aerosol generation. The effect was found to be sensitive to the organic carbon concentration in seawater and the algal exudate type. Diatomaceous exudate with organic carbon concentration (OC<0.2 μm >175 μM was required to observe a significant impact on the size distribution, which implies that effects are expected to be substantial only in high biological activity areas abundant with diatom algal populations. The laboratory findings were in agreement with analogous bubble-bursting experiments conducted with unfiltered

  1. Use of advanced particle methods in modeling space propulsion and its supersonic expansions

    Science.gov (United States)

    Borner, Arnaud

    droplet formation. Supersonic expansions to vacuum produce clusters of sufficiently small size that properties such as heat capacities and latent heat of evaporation cannot be described by bulk vapor thermodynamic values. Therefore, MD simulations are performed to compute the evaporation rate of small water clusters as a function of temperature and size and the rates are found to agree with Unimolecular Dissociation Theory (UDT) and Classical Nucleation Theory (CNT). The heat capacities and latent heat of vaporization obtained from Monte-Carlo Canonical-Ensemble (MCCE) simulations are used in DSMC simulations of two experiments that measured Rayleigh scattering and terminal dimer mole fraction of supersonic water-jet expansions. Water-cluster temperature and size are found to be influenced by the use of kinetic rather than thermodynamic heat-capacity and latent-heat values as well as the nucleation model. Additionally, MD simulations of water condensation in a one-dimensional free expansion are performed to simulate the conditions in the core of a plume. We find that the internal structure of the clusters formed depends on the stagnation temperature conditions. Clusters of sizes 21 and 324 are studied in detail, and their radial distribution functions (RDF) are computed and compared to reported RDFs for solid amorphous ice clusters. Dielectric properties of liquid water and water clusters are investigated, and the static dielectric constant, dipole moment autocorrelation function and relative permittivity are computed by means of MD simulations.

  2. 组织弹性测量之传统印压测试%Traditional Indentation Test for Measurement of Soft Tissue Elasticity

    Institute of Scientific and Technical Information of China (English)

    黄燕平; 郑永平

    2011-01-01

    与手触诊非常类似,印压测试使用比组织截面积小的压头对组织进行压缩,然后利用组织的反应力/形变测量组织的弹性特征.相对于触诊,印压测试的结果具有定量化和客观性强的优点,同时由于它对被测试组织准备没有特别的要求,可以进行无创测量,因此被大量用于各种活体组织弹性的测量,是应用最广泛的组织弹性测量技术之一.传统印压测试系统一般使用印压头的位移代替组织的形变,测试强调结果而不特别强调系统本身的实用性.近年来,该领域发展了一些新的印压系统,如超声印压和水冲印压系统,这些系统不仅可以很好地完成印压测试,而且具有便携性和可微型化的特点,所以在临床应用方面具有很大的前景,我们称这些系统为新型印压系统.本期我们主要介绍传统的印压测试和系统,先简要同顾它们的发展历史,然后重点介绍印压测试分析方法,以及在弹性测量里面的典型应用,最后小结全文.%As an analog of hand palpation,indentation test uses an indenter with a smaller contact area corupared to the tested soft tissue to compress it and utilizes the relationship of force/deformation to measure the elastic properties of the soft tissue.Compared to hand palpaation,the indentation is a method with quantitative results and objective analysis.With little requirement for the preparation of the tested soft tissue and as a noninvasive testing,the indentation has been widely applied to measure the tissue elasticity and has become one of the most frequently used methods in the field of elasticity measurement. Traditional indentation systems measure the displacement of indener as equivalent of the tissue deformation.The use of such system focues on the measurement results but pays little attention to the system aapplicability.In recent years,new indentation systems are emerging such as the ultrasound indentation and the water-jet

  3. Microhole High-Pressure Jet Drill for Coiled Tubing

    Energy Technology Data Exchange (ETDEWEB)

    Ken Theimer; Jack Kolle

    2007-06-30

    Tempress Small Mechanically-Assisted High-Pressure Waterjet Drilling Tool project centered on the development of a downhole intensifier (DHI) to boost the hydraulic pressure available from conventional coiled tubing to the level required for high-pressure jet erosion of rock. We reviewed two techniques for implementing this technology (1) pure high-pressure jet drilling and (2) mechanically-assisted jet drilling. Due to the difficulties associated with modifying a downhole motor for mechanically-assisted jet drilling, it was determined that the pure high-pressure jet drilling tool was the best candidate for development and commercialization. It was also determined that this tool needs to run on commingled nitrogen and water to provide adequate downhole differential pressure and to facilitate controlled pressure drilling and descaling applications in low pressure wells. The resulting Microhole jet drilling bottomhole assembly (BHA) drills a 3.625-inch diameter hole with 2-inch coil tubing. The BHA consists of a self-rotating multi-nozzle drilling head, a high-pressure rotary seal/bearing section, an intensifier and a gas separator. Commingled nitrogen and water are separated into two streams in the gas separator. The water stream is pressurized to 3 times the inlet pressure by the downhole intensifier and discharged through nozzles in the drilling head. The energy in the gas-rich stream is used to power the intensifier. Gas-rich exhaust from the intensifier is conducted to the nozzle head where it is used to shroud the jets, increasing their effective range. The prototype BHA was tested at operational pressures and flows in a test chamber and on the end of conventional coiled tubing in a test well. During instrumented runs at downhole conditions, the BHA developed downhole differential pressures of 74 MPa (11,000 psi, median) and 90 MPa (13,000 psi, peaks). The median output differential pressure was nearly 3 times the input differential pressure available from the

  4. Design and analysis of a novel latch system implementing fiber-reinforced composite materials

    Science.gov (United States)

    Guevara Arreola, Francisco Javier

    in the load-displacement slopes while the percentage of glass fiber increased. In the other hand, results showed that a detent made of only glass fiber layers was preferable than a carbon-glass fiber hybrid detent due to the high stresses shown in carbon fiber layers. Ultimately, forkbolt and detent were redesigned according to their functionality and test results. It was observed that the new design was stiffer than the original by showing a steeper load-displacement curve. Subsequently, an experimental procedure was performed in order to correlate computational model results. Fiber-reinforced composite forkbolt and detent were waterjet cut from a composite laminate manufactured by Vacuum Assisted Resin Transfer Molding (VART) process. Then, samples were tested according to the computational model. Six testing sample combinations of forkbolt and detent were tested including the top three woven iterations forkbolts from the computational model paired with woven and unidirectional glass fiber detents. Test results showed a stiffness drop of 15% when the carbon fiber percentage decreases from 100% to 75%. Also, it was observed that woven glass fiber detent was superior to the unidirectional glass fiber detent by presenting a forkbolt-detent stiffness 38% higher. Moreover, the new design of forkbolt and detent were tested showing a stiffness increment of 29%. Furthermore, it was observed that fiber-reinforced composite forkbolt and detent did not reach the desired load of 5000 N. However, the redesigned forkbolt made of 100% woven carbon fiber and the redesign detent made of 100% woven glass fiber were close to reach that load. The design review based on test results performed (DRBTR) showed that components did not fail where the computational model concluded to be the areas with the highest maximum principal stress. In contrast to the computational model, all samples failed at the contact area between forkbolt and detent.

  5. Comparison of mechanical properties obtained from conventional strength specimens and from as-sintered components%用常规强度试样与粉末冶金零件测定的力学性能的比较

    Institute of Scientific and Technical Information of China (English)

    Lorenz S.Sigl; Patrice Delarbre; Ulrike Jehring; 韩风麟

    2013-01-01

    由于零件的强度难以试验测定,因此通常都不使用这些数据.这篇论文介绍了一种可直接测定零件强度的新方法.这种方法是采用水射流切割(Water-jet Cutting),从零件上切割小型矩形试棒(尺寸约为40mm×5mm×5mm),经磨加工制备成试棒,用于测定力学性能.这篇论文将由高合金化Fe(Mo)-Ni-Cu粉末冶金钢制造的同步器齿毂作为典型零件,用由其上切割制成的矩形试棒测定了抗拉强度、冲击强度与三点弯曲的横向断裂强度,并将其和用常规拉伸试样(DIN EN ISO 2740)测定的强度与冲击性能进行了比较.由零件试棒和常规试样测定的性能完全一致,都在试验误差范围之内.为证明比较的有效性,还通过全面的化学与显微组织鉴定,对两种试样的相似性进行了核实.采用新方法评定了生产工艺变量对同步器齿毂的力学性能的影响.建立了小拉伸试棒的横向断裂强度与抗拉强度之间的相互关系.%Experimental access to the in-situ strength properties of components is difficult,which explains why such data are not generally available.The present paper introduces a new methodology which permits direct access to the strength properties of components.Such information is retrieved from small rectangular(40mm × 5mm × 5mm)which are prepared directiy from a component by water-jet cutting and subsequent grinding.Using a synchronizer-hub as a typical P/M component,the tensile strength,the impact resistance and the transverse rupture strength in 3-point bending were evaluated from these bars for a high-alloyed Fe (Mo)-Ni-Cu P/M steel,and compared to the strength and impact properties of conventional tensile specimens (DIN EN ISO 2740).Within the limits of experimental error,the data sets obtained from components and specimens are fully consistent.To confirm the validity of the comparison,the similarity of both specimen types is verified by a comprehensive chemical and microstructural

  6. 点源模型在旋转声源声场计算中的推广应用%Extended application of the point source model for the acoustic field solution of the rotating source

    Institute of Scientific and Technical Information of China (English)

    付建; 王永生

    2014-01-01

    In order to forecast the noise of circumvolve machines such as propellers, waterjets or pumps, the method of the point source model is studied to predict the loading noise of the rotating source in the frequency domain. The rotating source can be replaced by finite stationary sources distributing along the rotating trace, and the time differ-ence between sources can be transformed into phase differences in the frequency domain. The sound field of the ro-tating source is equal to the summation of all of the point sources. The veracity of the discretization method is vali-dated by the freedom sound field simulation of the rotating point source and rotating force source. And the require-ment of the number of discrete points of the rotating source with a different radius and frequency is analyzed. Final-ly, taking the single propeller blade as the object, two discretization methods of blade rotating force are put forward. One method is to take each acoustic mesh as a single force source, and the other method is to divide the blade into segments and each segment can be taken as a single force source. The validity of these discretization methods has been validated, which can provide the precondition for the extended application of the point source model for the sound field calculation of the rotating source.%针对螺旋桨、喷水推进器、风扇等旋转机械,研究了基于点源模型的旋转声源负载噪声频域预报方法。结合点源模型理论,将旋转声源离散为均匀分布在运动轨迹上的有限个固定声源,各声源间时域的迟滞时间转换为频域的相位差,所有点声源声场的总和即为旋转声源的声场。结合自由空间旋转点源和旋转力源声场仿真计算,验证了旋转声源离散方法的准确性;计算分析了不同半径、不同频率旋转声源对离散点数的要求;以单个螺旋桨叶片为对象,提出了叶片表面旋转力源按声场网格离散和分块离散的方

  7. Development of K-Basin High-Strength Homogeneous Sludge Simulants and Correlations Between Unconfined Compressive Strength and Shear Strength

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Yasuo; Baer, Ellen BK; Chun, Jaehun; Yokuda, Satoru T.; Schmidt, Andrew J.; Sande, Susan; Buchmiller, William C.

    2011-02-20

    K-Basin sludge will be stored in the Sludge Transport and Storage Containers (STSCs) at an interim storage location on Central Plateau before being treated and packaged for disposal. During the storage period, sludge in the STSCs may consolidate/agglomerate, potentially resulting in high-shear-strength material. The Sludge Treatment Project (STP) plans to use water jets to retrieve K-Basin sludge after the interim storage. STP has identified shear strength to be a key parameter that should be bounded to verify the operability and performance of sludge retrieval systems. Determining the range of sludge shear strength is important to gain high confidence that a water-jet retrieval system can mobilize stored K-Basin sludge from the STSCs. The shear strength measurements will provide a basis for bounding sludge properties for mobilization and erosion. Thus, it is also important to develop potential simulants to investigate these phenomena. Long-term sludge storage tests conducted by Pacific Northwest National Laboratory (PNNL) show that high-uranium-content K-Basin sludge can self-cement and form a strong sludge with a bulk shear strength of up to 65 kPa. Some of this sludge has 'paste' and 'chunks' with shear strengths of approximately 3-5 kPa and 380-770 kPa, respectively. High-uranium-content sludge samples subjected to hydrothermal testing (e.g., 185 C, 10 hours) have been observed to form agglomerates with a shear strength up to 170 kPa. These high values were estimated by measured unconfined compressive strength (UCS) obtained with a pocket penetrometer. Due to its ease of use, it is anticipated that a pocket penetrometer will be used to acquire additional shear strength data from archived K-Basin sludge samples stored at the PNNL Radiochemical Processing Laboratory (RPL) hot cells. It is uncertain whether the pocket penetrometer provides accurate shear strength measurements of the material. To assess the bounding material strength and

  8. Transurethral en bloc resection of bladder tumors

    Directory of Open Access Journals (Sweden)

    A. G. Martov

    2015-01-01

    Full Text Available Background. The high incidence of recurrent non-muscle-invasive bladder carcinoma (BC necessitates searches for new surgical methods. Objective: to comparatively evaluate the efficiency and safety of en block resection of bladder tumors versus transurethral resection (TUR. Subjects and methods. In January 2010 to June 2013, a total of 292 patients with primary and recurrent bladder tumor stages, cTa-T2, underwent transurethral endoscopic treatment (as TUR at the Unit of Minimally Invasive Urology, Moscow City Clinical Hospital Fifty-Seven. A major portion of these patients were included in the study of the efficiency and safety of en bloc TUR of bladder tumors. The criteria for study inclusion were primary or recurrent non-muscle-invasive bladder tumor measuring 1 to 3 cm, stage pTa-T1, signed informed consent to participate in the study and patients» readiness to undergo control examinations in inpatient setting for one year. The exclusion criteria were a confirmed or detected muscleinvasive tumor, multiple bladder involvement (> 3 tumors, as well as detected tumors spreading to the ureter, bladder neck, and prostatic urethra. The primary study endpoint was considered to be a recurrence of a tumor after TUR of the bladder (TURB. The secondary endpoint was the frequency of concealed bladder perforation, blood transfusions, recystoscopies for bladder tamponade, early recystoscopies to specify a BC stage, and the frequency of immediate intravesical injection of a chemical. For final analysis, the investigators selected 106 patients in a group where tumors were removed en bloc (a study group and 133 patients in a group where tumors were retrieved using traditional TURB (a control group. In the study group, the tumor was removed en bloc by a monopolar J-shaped electrode (sand wedge electrode in 45 patients, by a hook-like electrode in 14, by a hybrid procedure (hydropreparation and monopolar electrosurgery by a water-jet hybrid knife in 10, and by

  9. Transurethral en bloc resection of bladder tumors

    Directory of Open Access Journals (Sweden)

    A. G. Martov

    2015-03-01

    Full Text Available Background. The high incidence of recurrent non-muscle-invasive bladder carcinoma (BC necessitates searches for new surgical methods. Objective: to comparatively evaluate the efficiency and safety of en block resection of bladder tumors versus transurethral resection (TUR. Subjects and methods. In January 2010 to June 2013, a total of 292 patients with primary and recurrent bladder tumor stages, cTa-T2, underwent transurethral endoscopic treatment (as TUR at the Unit of Minimally Invasive Urology, Moscow City Clinical Hospital Fifty-Seven. A major portion of these patients were included in the study of the efficiency and safety of en bloc TUR of bladder tumors. The criteria for study inclusion were primary or recurrent non-muscle-invasive bladder tumor measuring 1 to 3 cm, stage pTa-T1, signed informed consent to participate in the study and patients» readiness to undergo control examinations in inpatient setting for one year. The exclusion criteria were a confirmed or detected muscleinvasive tumor, multiple bladder involvement (> 3 tumors, as well as detected tumors spreading to the ureter, bladder neck, and prostatic urethra. The primary study endpoint was considered to be a recurrence of a tumor after TUR of the bladder (TURB. The secondary endpoint was the frequency of concealed bladder perforation, blood transfusions, recystoscopies for bladder tamponade, early recystoscopies to specify a BC stage, and the frequency of immediate intravesical injection of a chemical. For final analysis, the investigators selected 106 patients in a group where tumors were removed en bloc (a study group and 133 patients in a group where tumors were retrieved using traditional TURB (a control group. In the study group, the tumor was removed en bloc by a monopolar J-shaped electrode (sand wedge electrode in 45 patients, by a hook-like electrode in 14, by a hybrid procedure (hydropreparation and monopolar electrosurgery by a water-jet hybrid knife in 10, and by

  10. A simple and rapid method for collecting saliva to assess sodium status in sheepum Um método simples e rápido de colheita de saliva para avaliar estados normais ou deficientes de sódio, em ovinos

    Directory of Open Access Journals (Sweden)

    Enrico Lippi Ortolani

    1997-06-01

    Full Text Available Fifteen lambs were fed diet with normal (0.11% or deficient levels of sodium ( 0.035%, respectively, for five weeks on each diet. At the end of each period saliva was collected by three different methods: swabbing with a 5 x 5 x 1.25cm synthetic sponge, aspiration with a 15cm long plastic tube connected to a 20ml syringe and sucking with a 4mm x 45cm long plastic tube through a water-jet aspirator pump or an eletric motor pump. The volume of saliva collected/min and the salivary sodium: potassium ratio were analysed. Larger volume of saliva was obtained with the developed sucking apparatus than with the sponge or the syringe. There was no influence of the method of saliva collection on the values of salivary Na:K ratio in both periods. Nevertheless, the lower the sodium dietary level was, the smaller the salivary Na:K ratio. Five weeks of low sodium diet intake resulted in a decrease in the salivary Na:K ratio values by half. However, the lambs did not exhibit any clinical sign of sodium deficiency. The advantages of the developed method to collect saliva are discussed.Neste experimento foram utilizados 15 cordeiros os quais receberam dietas com níveis adequados de sódio (0,11% ou deficientes deste elemento (0,035%, respectivamente, por dois períodos de cinco semanas cada. Ao término de cada período, foram colhidas amostras de saliva, de todos animais, por três diferentes métodos: absorção com o uso de uma esponja sintética com as seguintes medidas 5 x 5 x 1,25cm; aspiração com um tubo plástico de 15cm de comprimento conectado a uma seringa de 20ml; e através de sucção por tubo plástico, com 4mm x 45cm de comprimento, ligado a uma trompa de vácuo conectada a uma torneira ou a uma bomba motora elétrica geradora de vácuo. Foram avaliados o volume de saliva colhida por minuto e a razão das concentrações de sódio:potásio salivar. Quantidades muito maiores de saliva (p < 0,001 foram colhidas através do método utilizando

  11. The application of Hybrid knife to peroral endoscopic myotomy for achalasia%海博刀在经口内镜下肌切开术治疗贲门失弛缓症中的临床应用

    Institute of Scientific and Technical Information of China (English)

    令狐恩强; 翟亚奇; 李惠凯

    2012-01-01

    Objective To investigate the efficacy and safety of peroral endoscopic myotomy (POEM) with application of Hybrid knife (O-type).Methods POEM with Hybrid knife,was performed on 6 patients confirmed achalasia (AC) between January to August 2012 in PLA General Hospital.Datum of those patients was analyzed,as well as those who underwent conventional POEM during the same period.Difference in duration of different procedures and complication incidence was compared between two groups.Results All the 6 patients underwent POEM with Hybrid knife successfully.Among them,5 were female and 1 male.The median ages were 36.5 years(21-59 years) and median duration were 41.5 months (6-100 months).In Hybrid knife group,the duration time of whole operation,tunnel built-up and sphincter muscle dissection,was (52.3 ± 8.0)min,(28.8-± 3.9)min,(7.5 ± 1.2)min,respectively,while that of procedure with conventional POEM was (63.0 ± 12.9)min,(35.4 ± 7.5)min,(10.0 ± 3.0)min.Compared with conventional group,it took much less time in the process of the whole operation,tunnel built-up and muscle dissection in Hybrid knife group (P =0.020,P =0.001,P =0.005).Nocomplications were encountered in Hybrid knife group.However,5 patients developed complications in the conventional group (5/29,17.2 %),2 for mucosa perforation,1 for subcutaneous emphysema,1 for emphysema in both neck,mediastinum and abdominal cavity,1 for Pneumothorax combined with subcutaneous emphysema.Conclusions It suggested that Hybrid knife not only could complete POEM successfully,but also improve safety and increase operation speed,combined with water-jet and electrosurgery techniques.Meantime,study on a large scale are still awaited.%目的 探讨海博刀(O型)行经口内镜下肌切开术(POEM)治疗贲门失弛缓症(AC)的安全性和可行性.方法 2012年1~9月确诊为AC,并用海博刀行横开口法POEM的患者6例(海博刀组),男1例,女5例.选取同期用常规方法行POEM的患者29例(常规组)作为

  12. Modeling and preliminary characterization of passive, wireless temperature sensors for harsh environment applications based on periodic structures

    Science.gov (United States)

    Delfin Manriquez, Diego I.

    completed, the optimal configuration for the GMRF sensor was found to be the with an alumina slab with a thickness of 1.524 mm, two titanium screens with a thickness of 0.508, the use of metallic side reflectors and a side length of 49.525 mm. For the metamaterial, the process aforementioned resulted in a sensor design composed of a BTO/BN ceramic substrate and copper washers with 3.5 mm in OD and 1.6 mm in ID; the sensor side length was of 101.7 mm and design thickness was chosen to be 3.175 mm. The performed simulations resulted in several peaks in a 6 -- 18 GHz frequency range for both the reflection and transmission spectra. The limitation of the periodicity had a detrimental effect on the response of the sensor; however, a final sensor design was achieved with visible response in both the reflection and transmission regions. Fabrication was carried over using water-jet cutting and traditional machining methods for the GMRF sensor, while a traditional powder compression method was employed for the metamaterial sensor. For the former, titanium screens were used, while aluminum and steel plates were employed on the second one. Commercially available alumina ceramic was employed for both fabrication methods. As for the metamaterial sensor, the fabrication was done by utilizing a mixture of 70% boron nitride/30% barium titanate with an added 7.5% wt. PVA for structural rigidity. Final dimensions of 50.8 mm in side length and a thickness of 3.175 mm were achieved. Samples fabricated showed good structural integrity and manageability. Preliminary free space measurements were performed using a Programmable Network Analyzer (PNA) and a set of X-band horn antennas and Gaussian beam antennas to characterize the response of both the GMRF and the metamaterial sensors, respectively. No visible peak was observed for the GMRF sensor in the frequency region. The lack of response might be attributed to fabrication errors. For the metamaterial sensor, a strong response at 14.47 GHz mark