Riser pipe elevator

Energy Technology Data Exchange (ETDEWEB)

Bennett, W.; Jimenez, A.F.

1987-09-08

This patent describes a method for storing and retrieving a riser pipe, comprising the steps of: providing an upright annular magazine comprised of an inside annular wall and an outside annular wall, the magazine having an open top; storing the riser pipe in a substantially vertically oriented position within the annular magazine; and moving the riser pipe upwardly through the open top of the annular magazine at an angle to the vertical along at least a portion of the length of the riser pipe.

Engineering Task Plan for simulated riser installation by use of rotary drilling

International Nuclear Information System (INIS)

Barnes, G.A.

1995-12-01

This task is being performed to demonstrate the feasibility of the best riser installation alternative identified in the Engineering Study. This Engineering Task Plan (ETP) will be the WHC project management plan for the riser installation demonstration activities

Continuous composite riser

Energy Technology Data Exchange (ETDEWEB)

Slagsvold, L. [ABB Offshore Systems (Norway)

2002-12-01

The industry is now looking at developing reserves in waters depths of up to 3000 m (10000 ft). When moving into deeper waters the un-bonded flexible riser becomes very heavy and introduces large hang-off forces on the vessel. We are therefore investigating riser concepts incorporating new materials and with a simpler cross section that can be used for floating production. Advanced composite materials have properties such as, low weight, high strength, good durability and very good fatigue performance. Composite materials are slowly being exploited in the oil industry; they are being prototype tested for drilling risers and small diameter lines. Part of the process for the industry to accept larger diameter production risers made out of composite materials is to understand both the advantages and limitations. A new continuous composite riser system is being developed which capitalizes on the technical benefits of this material while addressing the known constraints. The fully bonded riser is being developed for ultra deep waters and its' characteristics include high temperature (160 deg C), high pressure (500 barg min), light weight, chemical resistant, good insulation, excellent fatigue characteristics and installation by reeling. The concept is based on the use of a thermoplastic liner together with a thermoplastic carbon fibre composite. This paper summarises the ongoing development, which has a goal to manufacture and qualify an 8'' riser, and includes all the steps in a production process from material qualification to the winding process and analytical modelling. (author)

Numerical Modeling and Mechanical Analysis of Flexible Risers

OpenAIRE

Li, J. Y.; Qiu, Z. X.; Ju, J. S.

2015-01-01

ABAQUS is used to create a detailed finite element model for a 10-layer unbonded flexible riser to simulate the riser’s mechanical behavior under three load conditions: tension force and internal and external pressure. It presents a technique to create detailed finite element model and to analyze flexible risers. In FEM model, all layers are modeled separately with contact interfaces; interaction between steel trips in certain layers has been considered as well. FEM model considering contact ...

A numerical simulation of VIV on a flexible circular cylinder

International Nuclear Information System (INIS)

Xie Fangfang; Deng Jian; Zheng Yao; Xiao Qing

2012-01-01

In this paper, numerical simulations of a flexible circular cylinder subjected to a vortex-induced vibration (VIV) are conducted. The Reynolds number for simulations is fixed at 1000. The finite volume method is applied for modeling fluid flow with the moving meshes feature. The dynamic response of a flexible cylinder fixed at both ends is modeled by the Euler–Bernoulli beam theory. The comparison between two-dimensional (2D) simulations and 3D simulations for the flexible cylinder shows that the maximum response amplitude of the cross-flow oscillation is about 0.57D for 2D rigid cylinders (modeled by a spring–damper–mass model) and 1.03D for flexible cylinders, respectively. The results from 3D simulations are closer to previous experimental results. Furthermore, the results obtained with various frequency ratios show that different wake patterns exist according to the frequency ratio, such as 2S mode, 2P mode and some more complicated modes. The wake pattern is different at various sections along the cylinder length, due to the fact that the two ends of the beam are fixed. The vibration of the flexible cylinder can also greatly alter the three dimensionality in the wake, which is our research in future work, especially in the transition region for Reynolds number ranging from 170 to 300. (paper)

Validation of mathematical models to describe fluid dynamics of a cold riser by gamma ray attenuation; Validacao de modelos matematicos para descrever a fluidodinamica de um riser utilizando atenuacao gama

Energy Technology Data Exchange (ETDEWEB)

Melo, Ana Cristina Bezerra Azedo de

2004-12-15

The fluid dynamic behavior of a riser in a cold type FCC model was investigated by means of catalyst concentration distribution measured with gamma attenuation and simulated with a mathematical model. In the riser of the cold model, MEF, 0,032 m in diameter, 2,30 m in length the fluidized bed, whose components are air and FCC catalyst, circulates. The MEF is operated by automatic control and instruments for measuring fluid dynamic variables. An axial catalyst concentration distribution was measured using an Am-241 gamma source and a NaI detector coupled to a multichannel provided with a software for data acquisition and evaluation. The MEF was adapted for a fluid dynamic model validation which describes the flow in the riser, for example, by introducing an injector for controlling the solid flow in circulation. Mathematical models were selected from literature, analyzed and tested to simulate the fluid dynamic of the riser. A methodology for validating fluid dynamic models was studied and implemented. The stages of the work were developed according to the validation methodology, such as data planning experiments, study of the equations which describe the fluidodynamic, computational solvers application and comparison with experimental data. Operational sequences were carried out keeping the MEF conditions for measuring catalyst concentration and simultaneously measuring the fluid dynamic variables, velocity of the components and pressure drop in the riser. Following this, simulated and experimental values were compared and statistical data treatment done, aiming at the required precision to validate the fluid dynamic model. The comparison tests between experimental and simulated data were carried out under validation criteria. The fluid dynamic behavior of the riser was analyzed and the results and the agreement with literature were discussed. The adopt model was validated under the MEF operational conditions, for a 3 to 6 m/s gas velocity in the riser and a slip

Composite risers for deep-water offshore technology: Problems and prospects. 1. Metal-composite riser

Science.gov (United States)

Beyle, A. I.; Gustafson, C. G.; Kulakov, V. L.; Tarnopol'skii, Yu. M.

1997-09-01

Prospects for the application of advanced composites in the offshore technology of oil production are considered. The use of composites in vertical pipelines-risers seems to be the most efficient. The operating loads are studied and the attendant problems are formulated. A comparative analysis of the characteristics of metal, composite, and metal-composite deep-water risers is presented. A technique is developed for designing multilayered risers, taking into account the action of internal and external pressures, gravity, and the axial tensile force created by tensioners, as well as the residual technological stresses due to the difference in coefficients of thermal expansion, physical-chemical shrinkage, and force winding. Numerical estimations are given for a two-layered riser with an inner metal layer of steel, titanium, or aluminum alloys and a composite layer of glass- or carbon-fiber plastics formed by circumferential winding. It is shown that the technological stresses substantially affect the characteristics of the riser.

modelling and modelling and simulation of coking in the riser

African Journals Online (AJOL)

eobe

into the modeling of FCC riser by predicting catalyst coke content as a function of reaction by predicting ... understanding of the process, hence restricting scale up to within the ... MATLAB (R2009a) on a Compaq HP CQ61 laptop. The following ...

Validation of mathematical models to describe fluid dynamics of a cold riser by gamma ray attenuation

International Nuclear Information System (INIS)

Melo, Ana Cristina Bezerra Azedo de

2004-12-01

The fluid dynamic behavior of a riser in a cold type FCC model was investigated by means of catalyst concentration distribution measured with gamma attenuation and simulated with a mathematical model. In the riser of the cold model, MEF, 0,032 m in diameter, 2,30 m in length the fluidized bed, whose components are air and FCC catalyst, circulates. The MEF is operated by automatic control and instruments for measuring fluid dynamic variables. An axial catalyst concentration distribution was measured using an Am-241 gamma source and a NaI detector coupled to a multichannel provided with a software for data acquisition and evaluation. The MEF was adapted for a fluid dynamic model validation which describes the flow in the riser, for example, by introducing an injector for controlling the solid flow in circulation. Mathematical models were selected from literature, analyzed and tested to simulate the fluid dynamic of the riser. A methodology for validating fluid dynamic models was studied and implemented. The stages of the work were developed according to the validation methodology, such as data planning experiments, study of the equations which describe the fluidodynamic, computational solvers application and comparison with experimental data. Operational sequences were carried out keeping the MEF conditions for measuring catalyst concentration and simultaneously measuring the fluid dynamic variables, velocity of the components and pressure drop in the riser. Following this, simulated and experimental values were compared and statistical data treatment done, aiming at the required precision to validate the fluid dynamic model. The comparison tests between experimental and simulated data were carried out under validation criteria. The fluid dynamic behavior of the riser was analyzed and the results and the agreement with literature were discussed. The adopt model was validated under the MEF operational conditions, for a 3 to 6 m/s gas velocity in the riser and a slip

Damage localization of marine risers using time series of vibration signals

Science.gov (United States)

Liu, Hao; Yang, Hezhen; Liu, Fushun

2014-10-01

Based on dynamic response signals a damage detection algorithm is developed for marine risers. Damage detection methods based on numerous modal properties have encountered issues in the researches in offshore oil community. For example, significant increase in structure mass due to marine plant/animal growth and changes in modal properties by equipment noise are not the result of damage for riser structures. In an attempt to eliminate the need to determine modal parameters, a data-based method is developed. The implementation of the method requires that vibration data are first standardized to remove the influence of different loading conditions and the autoregressive moving average (ARMA) model is used to fit vibration response signals. In addition, a damage feature factor is introduced based on the autoregressive (AR) parameters. After that, the Euclidean distance between ARMA models is subtracted as a damage indicator for damage detection and localization and a top tensioned riser simulation model with different damage scenarios is analyzed using the proposed method with dynamic acceleration responses of a marine riser as sensor data. Finally, the influence of measured noise is analyzed. According to the damage localization results, the proposed method provides accurate damage locations of risers and is robust to overcome noise effect.

Reliability-based dynamic positioning of floating vessels with riser and mooring system

DEFF Research Database (Denmark)

Fang, Shaoji; Leira, Bernt J.; Blanke, Mogens

2011-01-01

To maintain safety of a floating vessel with associated slender components such as risers and mooring line, the vessel is normally kept within a limited region. To specify a safe position in that region, this paper suggests a new position chasing algorithm with the consideration of both riser ang...... to their criticality. An optimal position set-point is produced by minimization of the value of the cost function. Numerical simulations show the effectiveness of the proposed algorithm....

Investigation and Control of VIVs with Multi-Lock-in Regions on Wide Flat Box Girders

Directory of Open Access Journals (Sweden)

Bo Wu

2017-01-01

Full Text Available On the preliminary designing of a wide flat box girder with the slenderness ratio 12, vertical and torsional vortex-induced vibrations (VIV are observed in wind tunnel tests. More than one lock-in region, which are defined as “multi-lock-in regions,” are recorded. Therefore, suspicions should be aroused regarding the viewpoint that wide box girders are aerodynamic friendly. As the three nascent vortexes originating at the pedestrian guardrails and inspection rails shed to near-wake through different pathways with different frequencies, the mechanisms of VIVs and multi-lock-in regions are analyzed to be determined by the inappropriate subsidiary structures. A hybrid method combining Large Eddy Simulation (LES with experimental results is introduced to study the flow-structure interactions (FSI when undergoing VIVs; the vortex mode of torsional VIV on wide flat box girders is defined as “4/2S,” which is different from any other known ones. Based on the mechanism of VIV, a new approach by increasing ventilation rate of the pedestrian guardrails is proved to be effective in suppressing vertical and torsional VIVs, and it is more feasible than other control schemes. Then, the control mechanisms are deeper investigated by analyzing the evolution of vortex mode and FSI using Hybrid-LES method.

Reconstruction of Twist Torque in Main Parachute Risers

Science.gov (United States)

Day, Joshua D.

2015-01-01

The reconstruction of twist torque in the Main Parachute Risers of the Capsule Parachute Assembly System (CPAS) has been successfully used to validate CPAS Model Memo conservative twist torque equations. Reconstruction of basic, one degree of freedom drop tests was used to create a functional process for the evaluation of more complex, rigid body simulation. The roll, pitch, and yaw of the body, the fly-out angles of the parachutes, and the relative location of the parachutes to the body are inputs to the torque simulation. The data collected by the Inertial Measurement Unit (IMU) was used to calculate the true torque. The simulation then used photogrammetric and IMU data as inputs into the Model Memo equations. The results were then compared to the true torque results to validate the Model Memo equations. The Model Memo parameters were based off of steel risers and the parameters will need to be re-evaluated for different materials. Photogrammetric data was found to be more accurate than the inertial data in accounting for the relative rotation between payload and cluster. The Model Memo equations were generally a good match and when not matching were generally conservative.

Reliable Radiographic Inspection of Flexible Risers for the Oil Industry

Science.gov (United States)

Almeida, Rômulo M.; Rebello, Joao Marcos A.; Vaz, Murilo A.

2010-02-01

Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

RELIABLE RADIOGRAPHIC INSPECTION OF FLEXIBLE RISERS FOR THE OIL INDUSTRY

International Nuclear Information System (INIS)

Almeida, Romulo M.; Rebello, Joao Marcos A.; Vaz, Murilo A.

2010-01-01

Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

Three-Dimensional Dynamics of a Flexible Marine Riser Undergoing Large Elastic Deformations

International Nuclear Information System (INIS)

Raman-Nair, W.; Baddour, R.E.

2003-01-01

The equations of the three dimensional motion of a marine riser undergoing large elastic deformations are formulated using Kane's formalism. The riser is modeled using lumped masses connected by extensional and rotational springs including structural damping. Surface waves are described by Stokes? second-order wave theory. Fluid-structure coupling is achieved by application of the hydrodynamic loads via Morison's equation and added-mass coefficients using the instantaneous relative velocities and accelerations between the fluid field and the riser segments. In the same way, a model for incorporating the effects of vortex-induced lift forces is included. The effect of internal flow is included in the model. The detailed algorithm is presented and the equations are solved using a robust implementation of the Runge-Kutta method provided in MATLAB. The mathematical model and associated algorithm are validated by comparing the steady-state equilibrium configuration of the riser with special cases of an elastic catenary mooring line and large deflection statics of a cantilever beam. The results of sample simulations are presented

Steel catenary risers supported by subsurface buoy

OpenAIRE

Adebayo, Addayo

2011-01-01

Master's thesis in Offshore technology Oil and gas exploration and production activities in deep and ultra deep waters in hostile environments necessitates the need to develop innovative riser systems capable of ensuring transfer of fluids from the seabed to a floating vessel and vice versa, with little or no issues with respect to influences of environmental loads and vessel motions. Over the years, studies have shown that the conventional flexible riser and steel catenary riser config...

Reliability analysis of wake-induced collision of flexible risers

OpenAIRE

Fu, Ping; Leira, Bernt Johan; Myrhaug, Dag

2017-01-01

Collision between risers is an important design and operational concern, especially in deep water since the probability of collision tends to increase as the riser length increases. Riser collision is due to the joint effects of many processes, i.e. environmental loads, hydrodynamic interference and surface floater motions and the most of them are stochastic processes. This paper provides an approach for estimating the failure probability of riser collision by considering these joint effects ...

Oscillation of a rigid catenary riser due to the internal two-phase flow

Energy Technology Data Exchange (ETDEWEB)

Bordalo, Sergio N.; Morooka, Celso K.; Cavalcante, Cesar C.P. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Matt, Cyntia G.C.; Franciss, Ricardo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

2008-07-01

Production of petroleum reservoirs from deep and ultra-deep waters is of paramount importance in Brazil, and several researches are necessary to develop appropriated equipment and risers for those operational conditions. Risers are suspended pipes used to transport the petroleum fluids between the seabed and the floating production unit. The structural flexibility of riser's lines is conferred by its length when compared with the diameter, characterizing it as a slender body. The risers are submitted to large static and dynamic loads originated from its own weight, waves, currents, platform motions and the internal flow. These loadings may threaten, by fatigue, the structural integrity of the system, compromising its useful life, and so they must be considered in the riser's project. There is a large amount of knowledge in the literature about the effects of external loadings on these systems, but the effect of the internal flow remains vastly unexplored. The variation of the flow mass and momentum inside the riser causes a dynamic loading on this system, originating an oscillatory motion. Furthermore, the gas-liquid two-phase flow may assume several flow patterns (bubble, slug, intermittent or annular), each one possessing completely different characteristics. In this work, the influence of the internal flow on the oscillatory motion (whipping motion) of catenary risers is analyzed. To provide a better understanding of this physical phenomenon, a scaled apparatus was designed and built. The material used to manufacture the riser's model was a flexible silicone tube, and air and water were used to simulate the two-phase flow. The instrumentation used to measure the fluids flow rates and the sustaining force at the top of the model was installed in the apparatus. A video acquisition system was used to determine the displacements, and frequency spectrum, of color targets positioned throughout the model, under several flow conditions. The flow patterns

Riser configuration, Tank 241-A-105, light duty utility arm

International Nuclear Information System (INIS)

Boucher, T.D.

1994-01-01

The light-duty utility arm (LDUA) is a seven-joint stainless steel robotic arm with a payload capacity of 75 lb. The robotic arm is deployed vertically with a maximum vertical reach of 63 ft. and a maximum horizontal reach of 13.5 ft. The functional requirements of the LDUA system are mapping and characterization of waste in Hanford single-shell tanks (SST) before and during waste retrieval. The LDUA system consists of a mobile deployment system (MDS), a vertical positioning mast (VPM), a tank riser interface confinement (TRIC), the LDUA, and a controller subsystem or support trailer. Currently, the system is in design and is subject to change; however, the LDUA or robotic arm will be deployed through a 12-in. riser above the tank dome. Field trips were performed to gather specifics for future deployment of the LDUA in Tank 241-A-105. The purpose of this report is to support two previous reports for the investigation of SSTs for deployment of the LDUA system. The first report identified the availability of risers while the second report identified the availability of Tanks 241-A-105, 241-A-S-109, 241-A-T-101, and 241-A-T-109 for deployment of the LDUA system. The second report also identified those 4- and 12-in. risers that could be used for deployment of the LDUA and camera system. This report addresses accessibility to the 241-A Tank Farm and the usability of the Tank 241-A-105 risers. The following information for assisting in the design and deployment of the LDUA will be discussed in this report: radiation survey; flange identification; high resolution video; computer simulated model; and field survey

Natural Frequencies and Mode Shapes of Statically Deformed Inclined Risers

KAUST Repository

Alfosail, Feras

2016-10-15

We investigate numerically the linear vibrations of inclined risers using the Galerkin approach. The riser is modeled as an Euler-Bernoulli beam accounting for the nonlinear mid-plane stretching and self-weight. After solving for the initial deflection of the riser due to self-weight, we use a Galerkin expansion employing 15 axially loaded beam mode shapes to solve the eigenvalue problem of the riser around the static equilibrium configuration. This yields the riser natural frequencies and corresponding exact mode shapes for various values of inclination angles and tension. The obtained results are validated against a boundary-layer analytical solution and are found to be in good agreement. This constitutes a basis to study the nonlinear forced vibrations of inclined risers.

Prevention of pulsations caused by flexible risers

NARCIS (Netherlands)

Belfroid S.P.C; Golliard, J.; Korst, H.J.C.

2013-01-01

In the last few decades, flexible risers have increasingly been used in the offshore oil and gas industry. In gas applications these risers can generate high amplitude tonal pressure fluctuations when the gas velocity reaches a threshold value. The resulting pressure fluctuations can then cause high

Analysis of the Suppression Device as Vortex Induced Vibration (VIV Reducer on Free Span using Finite Element Method

Directory of Open Access Journals (Sweden)

Dwi Priyanta

2016-12-01

Full Text Available Subsea pipeline is a transportation infrastructure of oil and gas as an alternative for ship tanker. The uneven topography surface of the sea floor resulting the pipe undergoes free span. The free span is a condition endured by the pipe where the pipe position has  distance or gap with the seabed supported by two pivot. The free span is at risk of experiencing a vibration caused by the presence of dynamic load that is current and the wave. The vibration that occurs is the impact of the presence of the phenomenon of Vortex Induced Vibration (VIV. The Phenomenon Of VIV occur on a cylindrical component caused by ocean currents, causing the occurrence of vibration by the movement of fluid on the pipe so that it raises the vortex at the rear of the direction of oncoming flow. One way to dampen or reduce the impact of VIV is by adding suppresion device. VIV suppression device is a tool that is installed on the pipeline on offshore piping installationcthat serves to dampen or reduce the impact of VIV. One of the simulations used to know the characteristics of a fluid is to use (CFD Computational Fluid Dynamic. With the addition of suppression device can add the rest of the operating time on a free span of affected VIV, on the condition of free span critical exposed VIV (Vortex Induced Vibration value has a life time on plain pipe 44.21 years, on pipe with 53.09 years and Fairing on the pipe with the Helical strike 52.95 year.

1000 meters water depth rigid TLP riser; Riser rigido de plataforma de pernas atirantadas para lamina d'agua de 1000 metros

Energy Technology Data Exchange (ETDEWEB)

Braga, Mauro Jacinto Pastor

1990-07-01

A procedure to estimate the fatigue life of a TLP riser in 1000 meters water depth based on a hydro-elastic analysis of an integrated riser-TLP model in the time domain is presented . The computational architecture is shown that makes it feasible to process and store the great amount of data involved. The procedure is applied to a 1000 meters water depth TLP with a set of 40 risers 8 inches in diameter equipped with a floatation layer. (author)

Flexible riser integrity management: areas of concern and applications

Energy Technology Data Exchange (ETDEWEB)

Podskarbi, Mateusz [Schlumberger Servicos de Petroleo Ltda., Rio de Janeiro, RJ (Brazil)

2008-07-01

Flexible risers are key enables for both deep water and shallow water offshore production developments. Number of flexible risers installed worldwide is into several thousands with two main concentration areas - offshore Brazil and North Sea. Flexible risers are subject to significant loads including environmental impacts, vessel motions, internal temperature and pressure as well as substantial installation loads. Excessive loads of one type or a combination of various types of loads can cause damage to the flexible that can lead to a catastrophic failure. Industry observed number of failures increasing in recent years. Operators and manufacturing companies are taking various steps to address this issue. One of possible approaches is to use monitoring instrumentation to measure riser response and integrity in real time. This paper reviews various types of flexible riser damage mechanisms caused by impact damage, corrosion, excessive pressure, armor wire rupture, compromising flexible riser minimum bend radius, excessive fatigue loading, etc. Failure mechanisms are reviewed with particular focus on the consequences that it causes in terms of risk to the infrastructure and detectable changes. Further part of the paper is focused on monitoring techniques employed and available to detect particular types of failure mechanisms. Systematic review of the monitoring techniques is provided with specific attention given to ability of these techniques to provide early warnings of riser failure. Evaluation of monitoring techniques versus modes of operation and failure mechanism is key to selecting appropriate system that ensures effectiveness of the integrity management program. (author)

Vector form Intrinsic Finite Element Method for the Two-Dimensional Analysis of Marine Risers with Large Deformations

Science.gov (United States)

Li, Xiaomin; Guo, Xueli; Guo, Haiyan

2018-06-01

Robust numerical models that describe the complex behaviors of risers are needed because these constitute dynamically sensitive systems. This paper presents a simple and efficient algorithm for the nonlinear static and dynamic analyses of marine risers. The proposed approach uses the vector form intrinsic finite element (VFIFE) method, which is based on vector mechanics theory and numerical calculation. In this method, the risers are described by a set of particles directly governed by Newton's second law and are connected by weightless elements that can only resist internal forces. The method does not require the integration of the stiffness matrix, nor does it need iterations to solve the governing equations. Due to these advantages, the method can easily increase or decrease the element and change the boundary conditions, thus representing an innovative concept of solving nonlinear behaviors, such as large deformation and large displacement. To prove the feasibility of the VFIFE method in the analysis of the risers, rigid and flexible risers belonging to two different categories of marine risers, which usually have differences in modeling and solving methods, are employed in the present study. In the analysis, the plane beam element is adopted in the simulation of interaction forces between the particles and the axial force, shear force, and bending moment are also considered. The results are compared with the conventional finite element method (FEM) and those reported in the related literature. The findings revealed that both the rigid and flexible risers could be modeled in a similar unified analysis model and that the VFIFE method is feasible for solving problems related to the complex behaviors of marine risers.

Contribution to the evaluation of vortex-induced vibrations analysis using 'wake oscillators' and 'vortex-tracking' models; Contribuicao a avaliacao dos modelos 'wake oscillator' e 'vortex tracking' para analise de vibracoes induzidas por vortices

Energy Technology Data Exchange (ETDEWEB)

Carneiro, Daniel L. [Bureau Veritas do Brasil, Rio de Janeiro, RJ (Brazil); Ellwanger, Gilberto B. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE); Galgoul, Nelson S. [SUPORTE Consultoria e Projetos, Rio de Janeiro, RJ (Brazil)

2008-07-01

Fatigue due to vortex-induced vibrations (VIV) is one of the major uncertainties today in the design of slender offshore structures, such as risers, pipelines, umbilicals, tendons and mooring lines, required for oil and gas production in deep waters. The absence of reliable tools for quantitative analyses of this phenomenon is a technological barrier, which is being faced by several research groups, generating tens of thesis and articles every year. This paper presents VIV results achieved by the author, using 'wake oscillator' and 'vortex tracking' models, when researching for his M. Sc. dissertation. Time domain analyses were performed using a commercial software. First results describe the response of the evaluated models for two degrees-of-freedom rigid cylinders, which were compared to values prescribed in recognized recommended practices. Afterwards, VIV analyses results for a steel catenary 10-inch diameter riser in three dimensional current profiles were compared to measured values. The considered riser, installed in 910 m water depth offshore Brazil, is possibly the only monitored SCR with no VIV suppression devices in the world today. The results were considered satisfactory, despite some discrepancies. The authors expect the presented results to contribute in further studies on these models. (author)

Composite Risers for Deepwater Applications Risers composites pour applications en mer profonde

Directory of Open Access Journals (Sweden)

Metivaud G.

2006-11-01

Full Text Available This paper is devoted to the high performance composite tubes developed by the Institut Français du Pétrole (IFP and Aerospatiale for deepwater risers applications. The design principles of the tubes are first presented, along with results of preliminary work carried out as part of the initial feasibility study. Applications of composite tubes to drilling riser Kill and Choke lines and to TLP production risers, both of which have been studied in detail, are then described. Technical and operational advantages obtained from such applications are discussed. Cet article présente les travaux réalisés par l'Institut Français du Pétrole et l'Aerospatiale dans le domaine des tubes composites haute performance pour les applications aux liaisons fond-surface de forage et de production en mer profonde. Les matériaux composites avancés sont une classe de matériaux très particulière, présentant à la fois des caractéristiques mécaniques élevées et une densité spécifique faible. Ils sont utilisés principalement par les industries de l'aéronautique et de l'espace, mais l'industrie pétrolière en mer profonde est un secteur où ils peuvent trouver dans l'avenir des applications très intéressantes, notamment les tubes de risers. Les tubes de risers pétroliers en mer présentent en effet une gamme de spécifications élevées (diamètres, pression, traction, fatigue dans un environnement sévère et leur poids suspendu peut pénaliser fortement les systèmes de forage ou de production par grande profondeur d'eau. Un premier concept de tube composite haute performance a été développé par IFP et Aerospatiale au début des années 1980 ; sa partie courante, réalisée par enroulement filamentaire de fibres de verre R ou de fibres de carbone, et son système d'embout ont été soumis à une série d'essais mécaniques (pression interne jusqu'à 105 MPa, traction supérieure à 1 000 kN pour un diamètre nominal de 0,1 m, millions de

Dynamic response of a riser under excitation of internal waves

Science.gov (United States)

Lou, Min; Yu, Chenglong; Chen, Peng

2015-12-01

In this paper, the dynamic response of a marine riser under excitation of internal waves is studied. With the linear approximation, the governing equation of internal waves is given. Based on the rigid-lid boundary condition assumption, the equation is solved by Thompson-Haskell method. Thus the velocity field of internal waves is obtained by the continuity equation. Combined with the modified Morison formula, using finite element method, the motion equation of riser is solved in time domain with Newmark-β method. The computation programs are compiled to solve the differential equations in time domain. Then we get the numerical results, including riser displacement and transfiguration. It is observed that the internal wave will result in circular shear flow, and the first two modes have a dominant effect on dynamic response of the marine riser. In the high mode, the response diminishes rapidly. In different modes of internal waves, the deformation of riser has different shapes, and the location of maximum displacement shifts. Studies on wave parameters indicate that the wave amplitude plays a considerable role in response displacement of riser, while the wave frequency contributes little. Nevertheless, the internal waves of high wave frequency will lead to a high-frequency oscillation of riser; it possibly gives rise to fatigue crack extension and partial fatigue failure.

Vivências da sexualidade durante a gravidez

OpenAIRE

Cruz, Maria Diana Fernandes da

2012-01-01

Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciada em Enfermagem Sumário Durante o período de gravidez, existem uma série de mudanças biológicas, psicológicas, culturais e sociais, estas podem ter influência na vivência da sexualidade. A vivência da sexualidade durante esta fase pode ser entendida de diversas formas pela gestante, muitas vezes pode ser um factor importante para a satisfação das necessidades acrescidas d...

Hydrodynamics of a natural circulation loop in a scaled-down steam drum-riser-downcomer assembly

Energy Technology Data Exchange (ETDEWEB)

Basu, Dipankar N., E-mail: dnbasu@iitg.ernet.in; Patil, N.D.; Bhattacharyya, Souvik; Das, P.K.

2013-12-15

Highlights: • Experimental investigation of loop hydrodynamics in a scaled-down simulated AHWR. • Identification of flow regimes and transition analyzing conductance probe signal. • Downcomer flow maximizes with fully developed churn flow and lowest for bubbly flow. • Highest downcomer flow rate is achieved with identical air supply to both risers. • Interaction of varying flow patterns reduces downcomer flow for unequal operation. - Abstract: Complex interactions of different phases, widely varying frictional characteristics of different flow regimes and the involvement of multiple scales of transport make the modelling of a two-phase natural circulation loop (NCL) exceedingly difficult. The knowledge base about the dependency of downcomer flow rate on riser-side flow patterns, particularly for systems with multiple parallel channels is barely developed, necessitating the need for detailed experimentation. The present study focuses on developing a scaled-down test facility relevant to the Advanced Heavy Water Reactor conceived in the atomic energy programme of India to study the hydrodynamics of the NCL using air and water as test fluids. An experimental facility with two risers, one downcomer and a phase-separating drum was fabricated. Conductivity probes and photographic techniques are used to characterize the two phase flow. Normalized voltage signals obtained from the amplified output of conductivity probes and their subsequent analysis through probability distribution function reveal the presence of different two-phase flow patterns in the riser tubes. With the increase in air supply per riser void fraction in the two-phase mixture increases and gradually flow patterns transform from bubbly to fully developed annular through slug, churn and dispersed annular flow regimes. Downcomer flow rate increases rapidly with air supply till a maximum and then starts decreasing due to enhanced frictional forces. However, the maximum value of downcomer water

How to inspect platform risers: an effective approach and new challenges

International Nuclear Information System (INIS)

Agthoven, Robert van

2007-01-01

Ageing risers on offshore platforms, designed and built several decades ago, were until recently hard to inspect or not inspectable at all. This was due to their layout or ID geometry changes prohibiting the use of product propelled intelligent pigs, which are frequently used, on long distance pipelines. Growing concerns about reliability and safety, as well as environmental pressure, are the impetus for operators of offshore platforms to check the condition of the risers, which until now could not be inspected. This paper describes a few solutions to enter these 'non-inspect-able' risers to check their condition by using special small diameter cable operated tools. These new miniature cable tools are spin-offs from the well-known cable (tether, umbilical) tools introduced more than two decades ago by RTD for the inspection of (off)-loading lines. The first generation gravity driven small diameter riser inspection tools were designed to inspect the vertical section of the riser only. On-going development has resulted in a second generation of riser inspection tools which can now enter a few hundred metres into the horizontal connecting pipeline on the sea-floor by using a small, but powerful, crawler. With this ability these tools are the only solution for riser-pipes and relatively short connecting pipelines which terminate at a T-or Y-connection in the vicinity of the platform. All riser inspection tools apply ultrasonics to quantify wall thickness and corrosion. A novel TOFD (Time Of Flight Diffraction) module can be applied as an option to inspect in the circumferential weld area. All cable tools have a reinforced cable, which is used for tool control and retrieval. A strong advantage of these cable tools is that they provide on-line results and allow on-site evaluation. Since the introduction of these new tools considerable experience has been gained. The history of development and several typical cases of applications are given in this paper. In addition

Evaluation of riser 14 temperature response

International Nuclear Information System (INIS)

OGDEN, D.M.

1999-01-01

The initial sluicing activities of Project WRSS resulted in a two month increase in temperatures as measured by the Riser 14 thermocouple tree of tank 241-C-106. While this increase was anticipated, the maximum temperature was higher than expected. An evaluation was performed to determine if adequate subcooling exists in the waste to continue sluicing activities. It was determined that a minimum of 10 F subcooling exists in the waste and that the higher Riser 14 temperatures were the result of higher than assumed waste saturation temperature

FCC riser quick separation system: a review

Directory of Open Access Journals (Sweden)

Zhi Li

2016-10-01

Full Text Available Abstract The riser reactor is the key unit in the fluid catalytic cracking (FCC process. As the FCC feedstocks become heavier, the product mixture of oil, gas and catalysts must be separated immediately at the outlet of the riser to avoid excessive coking. The quick separation system is the core equipment in the FCC unit. China University of Petroleum (Beijing has developed many kinds of separation system including the fender-stripping cyclone and circulating-stripping cyclone systems, which can increase the separation efficiency and reduce the pressure drop remarkably. For the inner riser system, a vortex quick separation system has been developed. It contains a vortex quick separator and an isolated shell. In order to reduce the separation time, a new type of separator called the short residence time separator system was developed. It can further reduce the separation time to less than 1 s. In this paper, the corresponding design principles, structure and industrial application of these different kinds of separation systems are reviewed. A system that can simultaneously realize quick oil gas separation, quick oil gas extraction and quick pre-stripping of catalysts at the end of the riser is the trend in the future.

Preliminary optimal configuration on free standing hybrid riser

Directory of Open Access Journals (Sweden)

Kyoung-Su Kim

2018-05-01

Full Text Available Free Standing Hybrid Riser (FSHR is comprised of vertical steel risers and Flexible Jumpers (FJ. They are jointly connected to a submerged Buoyancy Can (BC. There are several factors that have influence on the behavior of FSHR such as the span distance between an offshore platform and a foundation, BC up-lift force, BC submerged location and FJ length.An optimization method through a parametric study is presented. Firstly, descriptions for the overall arrangement and characteristics of FSHR are introduced. Secondly, a flowchart for optimization of FSHR is suggested. Following that, it is described how to select reasonable ranges for a parametric study and determine each of optimal configuration options. Lastly, numerical analysis based on this procedure is performed through a case study. In conclusion, the relation among those parameters is analyzed and non-dimensional parametric ranges on optimal arrangements are suggested. Additionally, strength analysis is performed with variation in the configuration. Keywords: Free standing hybrid riser, Hybrid riser system, Buoyancy can, Flexible jumper, Deepwater, Multi-body dynamics

Helical wire stress analysis of unbonded flexible riser under irregular response

Science.gov (United States)

Wang, Kunpeng; Ji, Chunyan

2017-06-01

A helical wire is a critical component of an unbonded flexible riser prone to fatigue failure. The helical wire has been the focus of much research work in recent years because of the complex multilayer construction of the flexible riser. The present study establishes an analytical model for the axisymmetric and bending analyses of an unbonded flexible riser. The interlayer contact under axisymmetric loads in this model is modeled by setting radial dummy springs between adjacent layers. The contact pressure is constant during the bending response and applied to determine the slipping friction force per unit helical wire. The model tracks the axial stress around the angular position at each time step to calculate the axial force gradient, then compares the axial force gradient with the slipping friction force to judge the helical wire slipping region, which would be applied to determine the bending stiffness for the next time step. The proposed model is verified against the experimental data in the literature. The bending moment-curvature relationship under irregular response is also qualitatively discussed. The stress at the critical point of the helical wire is investigated based on the model by considering the local flexure. The results indicate that the present model can well simulate the bending stiffness variation during irregular response, which has significant effect on the stress of helical wire.

Response prediction of long flexible risers subject to forced harmonic vibration

OpenAIRE

Riveros, Carlos Alberto; Utsunomiya, Tomoaki; Maeda, Katsuya; Itoh, Kazuaki

2010-01-01

Several research efforts have been directed toward the development of models for response prediction of flexible risers. The main difficulties arise from the fact that the dynamic response of flexible risers involves highly nonlinear behavior and a self-regulated process. This article presents a quasi-steady approach for response prediction of oscillating flexible risers. Amplitude-dependent lift coefficients are considered, as is an increased mean drag coefficient model during synchronizatio...

Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) Study of Mass-Transfer Mechanisms in Riser Flow.

Science.gov (United States)

Carlos Varas, Álvaro E; Peters, E A J F; Kuipers, J A M

2017-05-17

We report a computational fluid dynamics-discrete element method (CFD-DEM) simulation study on the interplay between mass transfer and a heterogeneous catalyzed chemical reaction in cocurrent gas-particle flows as encountered in risers. Slip velocity, axial gas dispersion, gas bypassing, and particle mixing phenomena have been evaluated under riser flow conditions to study the complex system behavior in detail. The most important factors are found to be directly related to particle cluster formation. Low air-to-solids flux ratios lead to more heterogeneous systems, where the cluster formation is more pronounced and mass transfer more influenced. Falling clusters can be partially circumvented by the gas phase, which therefore does not fully interact with the cluster particles, leading to poor gas-solid contact efficiencies. Cluster gas-solid contact efficiencies are quantified at several gas superficial velocities, reaction rates, and dilution factors in order to gain more insight regarding the influence of clustering phenomena on the performance of riser reactors.

Multidimensional analysis of developing two-phase flows in an ESBWR chimney with and without riser channels

International Nuclear Information System (INIS)

Murakawa, H.; Antal, S.P.; Lahey, R T.

2008-01-01

The object of this work was to simulate developing multidimensional velocity and void fraction distributions in bubbly and churn turbulent two-phase flows. An advanced Computational Multiphase Fluid Dynamics (CMFD) code, NPHASE, was used to perform three-dimensional, multi-field simulations of the developing phasic velocity and phase distributions in vertical adiabatic conduits. The NPHASE code employed a multi-field two-fluid model, in which, for churn turbulent flow, the vapor phase was divided into small and large, cap bubble fields. In addition, state-of-the-art interfacial area density and field-to-field mass transfer models were used for both the small and large, cap bubbles. In particular, the bubble breakup and coalescence processes were quantified using a two-group interfacial area density transport equation. This allowed the CMFD simulation of developing churn turbulent flows in an ESBWR with and without vertical riser channels in the chimney region above the core. Based on these simulations it was concluded that riser channels have little adverse effect on the induced natural circulation flow through the core and the stability characteristics of an ESBWR. (authors)

Engineering study - installation of new risers in Single-Shell Tanks

International Nuclear Information System (INIS)

Magruder, W.J.

1994-08-01

A sampling program is being developed to characterize the 149 underground SSTs on the Hanford Site. The sampling effort will require access to the tank interior in a minimum of two locations per tank. Some of the risers suitable for sampling are either unavailable or are not in locations for proper characterization of the tank contents. Additional risers will be required in the SSTs to support the tank characterization sampling program. The purpose of this engineering study is to review alternatives for installation of new riser in the SSTs

Pressured drilling riser design for drilling in ultra deep water with surface bop

Energy Technology Data Exchange (ETDEWEB)

Zhang, J.; Morrison, D.; Efthymiou, M.; Lo, K.H. [Shell Global Solutions, 78 - Velizy Villacoublay (France); Magne, E.; Leach, C. [Shell Internationale Exploration and Production (Netherlands)

2002-12-01

In conventional drilling with a semi-submersible rig valuable rig time is used to run and retrieve the BOP and its accessories on the seabed, and this time increases with water depth. Furthermore, use of the conventional sub-sea BOP requires a large-diameter riser, which requires substantial rig storage and deck load capacity prior to installation. It also requires high riser-tensioning capacity or additional buoyancy. Thus as the water depth increases, it leads to a need for heavy duty 4. and 5. generation rigs with escalation in costs. The high cost of deep-water drill rigs is leading to the development of Surface BOP technology. In this development, the BOP is placed above sea level and the riser is simply a continuation of the casing (typical diameter 13-3/8''). This eliminates the need for a heavy 21'' riser and for running the BOP to the sea bed and retrieving it. Moreover, the reduced tension requirement for the smaller riser extends the water depth capability of 3. generation drilling semi-submersibles, enabling them to drill in deeper waters. A critical success factor for this development is the ability to design the riser/casing to withstand high internal pressures due to well kicks, in addition to environmental loads, and to restrict vessel offsets within certain limits so as not to overload the riser under the prevailing weather conditions. This paper addresses the design considerations of a pressured drilling riser that can be used with a surface BOP in deep-water. Key design issues that are sensitive to ultra-deep-water applications are discussed. The technical aspects of using (disposable) standard casing with threaded connector for the drilling riser are discussed, with a particular emphasis on the connector fatigue-testing program to quantify the stress concentration factor for fatigue design. Emerging composite material offers some alternatives to the steel riser when drilling in ultra-deep water Design issues related to the

A case study on riser analysis of a drilling riser in deep waters; Estudo de caso: analises estruturais e hidrodinamicas de um riser de perfuracao em aguas profundas

Energy Technology Data Exchange (ETDEWEB)

Roveri, Francisco E.; Pestana, Rafael G. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

2008-07-01

This paper presents a set of structural and hydrodynamic analyses of a connected marine riser, in 1900 meter water depth. Operating windows are determined for one year return period environmental conditions and for a set of drilling fluid weight density values. Parametric analyses are carried out to study the riser response sensitivity to variations in environmental conditions, drilling fluid weight density, upper and lower flex joint rotational stiffness and vessel motion phase angles. Current, drilling fluid weight density and vessel motion phase angle changes affect significantly the system response, whereas the response is not significantly affected by changes in wave height, wave period and flex joint rotational stiffness. (author)

Stochastic dynamic analysis of marine risers considering Gaussian system uncertainties

Science.gov (United States)

Ni, Pinghe; Li, Jun; Hao, Hong; Xia, Yong

2018-03-01

This paper performs the stochastic dynamic response analysis of marine risers with material uncertainties, i.e. in the mass density and elastic modulus, by using Stochastic Finite Element Method (SFEM) and model reduction technique. These uncertainties are assumed having Gaussian distributions. The random mass density and elastic modulus are represented by using the Karhunen-Loève (KL) expansion. The Polynomial Chaos (PC) expansion is adopted to represent the vibration response because the covariance of the output is unknown. Model reduction based on the Iterated Improved Reduced System (IIRS) technique is applied to eliminate the PC coefficients of the slave degrees of freedom to reduce the dimension of the stochastic system. Monte Carlo Simulation (MCS) is conducted to obtain the reference response statistics. Two numerical examples are studied in this paper. The response statistics from the proposed approach are compared with those from MCS. It is noted that the computational time is significantly reduced while the accuracy is kept. The results demonstrate the efficiency of the proposed approach for stochastic dynamic response analysis of marine risers.

Development of a 14-inch ID High-Pressure Hybrid Riser for SBOP Drilling Développement d’un riser hybride 14”ID haute pression pour le forage SBOP

Directory of Open Access Journals (Sweden)

Persent E.

2009-11-01

Full Text Available This paper discusses the development of a 14-inch ID high-pressure hybrid riser (10 000 psi for surface BOP drilling in ultra-deep water (10 000 ft. The high-pressure hybrid riser system is obtained by adapting and combining two existing technologies, previously developed by the IFP for other applications: – the Clip connector, a double breech-block type connector to provide a quick and safe connection for riser joints; – hybrid pipe technology, a steel pipe hoop-wound with tapes of carbon fibers impregnated with polyamide thermoplastic resin. IFP has developed a new 14-inch ID HP Clip connector for the hybrid riser application. The connector is capable of withstanding a 2.8 million pound tension and a 10 000 psi operating pressure. In addition, a 16-inch nominal OD hybrid riser pipe has been designed to replace the steel riser pipe with a thinnerwalled hoop-wound steel pipe. The significant weight savings that can be achieved with the hybrid riser pipe make it possible to design an effective riser architecture to withstand the high pressure and deep water requirements. Pursuant to design studies, a 14-inch ID prototype assembly consisting of two hybrid riser pipe sections with a high-pressure Clip connector was manufactured. A test program, including burst and collapse tests as well as cyclic fatigue testing, was formulated and carried out to qualify the performance of the Clip connector and hybrid riser pipe system. Completion of hybrid pipe additional fatigue testing and realization of a scale-one field testing of the hybrid riser are considered as the next steps of the project. To date, the main test results (burst, collapse, fatigue resistance confirm that the Clip connector and the hybrid pipe technologies are well suited for ultra-deep sea drilling with a surface BOP. However, the fatigue resistance of hybrid riser pipes still needs to be better characterized. Cet article présente le développement d’un riser hybride 14”ID haute

Riser equipment decontamination engineering task plan

International Nuclear Information System (INIS)

BOGER, R.M.

1999-01-01

On October 15, 1998, two Characterization Project Operations (CPO) employees were found to have contaminated clothing. An operator had 300,000-dpm/100cm2 beta/gamma, no alpha, contamination on his coat sleeve and a Radiation Control Technician (RCT) had 10,000 dpm/100cm2 beta/gamma, no alpha, on his shirt sleeve. The CPO swing shift crew was working in TX tank farm, performing sampling activities at 241-TX-113. TX tank farm is a ''clean farm'' and does not require anti-contamination clothing for entry. The CPO personnel were dressed in normal work clothes. An operator and an RCT were performing a pre-job survey that involved removing bagging around the riser equipment. When the RCT saw that the contamination readings from smear samples of the riser equipment were greater than expected, the job was suspended. Crew members were then directed to areas of lower background radiation for personnel surveys. During personnel surveys, reportable contamination was found on the coat sleeve of the operator who had been involved in the pre-job survey and on the shirt sleeve of the RCT who had been involved in the pre-job survey. No other personnel were found to be contaminated. Because of this off normal event Characterization Engineering was given the following corrective action: Examine the process methodology used for core sampling operations to determine practicality and potential long-term advantages of reducing personnel contact with contaminated equipment. This Engineering Task Plan ensures that LMHC 1998a, Corrective Action No.7 is completely addressed by Characterization Engineering. The deliverable is an Engineering Study that evaluates decontamination of riser equipment components and considers additional engineered features to reduce potential exposure to workers operating the riser equipment. This engineering study shall also address any released design features that have failed to be implemented

Development and characterization of composite materials for production of composite risers by filament winding

Energy Technology Data Exchange (ETDEWEB)

Sobrinho, L.L.; Bastian, F.L. [Federal University of Rio de Janeiro, RJ (Brazil). Dept. of Metallurgical and Materials Engineering], e-mail: ledjane@metalmat.ufrj.br; Calado, V.M.A. [Federal University of Rio de Janeiro, RJ (Brazil). Escola de Quimica

2008-07-01

Industry has been challenged to provide riser systems which are more cost effective and which can fill the technology gaps with respect to water depth, riser diameter and high temperatures left open by flexible, steel catenary risers (SCRs) and hybrid risers. Composite materials present advantages over conventional steel risers because composite materials are lighter, more fatigue and corrosion resistant, better thermal insulators and can be designed for improving the structural and mechanical response. Besides, composite materials present some attractive attributes for the offshore service, such as: high specific strength and stiffness. This paper focuses on the development and characterization of a polymer matrix (epoxy) and of material composite (epoxy/fiber glass), which will be used in a development for composites risers by the filament winding process (wet winding). (author)

Registro e vivência

Directory of Open Access Journals (Sweden)

Diego Acevedo Aguilar

2013-06-01

Full Text Available A memória natural, ligada ao corpo e ao seu universo sensitivo, parece ter cedido lugar à memória instrumental, dependente da tecnologia e dos seus dispositivos. A cultura dá um giro radical: privilegia-se o registro em detrimento da vivência, a prova em relação à experiência. Ao menos é o que parece nesta passagem da religiosidade quitenha.

A state space approach for the eigenvalue problem of marine risers

KAUST Repository

Alfosail, Feras; Nayfeh, Ali H.; Younis, Mohammad I.

2017-01-01

A numerical state-space approach is proposed to examine the natural frequencies and critical buckling limits of marine risers. A large axial tension in the riser model causes numerical limitations. These limitations are overcome by using

Girassol, Riser Towers for ultra deep water

Energy Technology Data Exchange (ETDEWEB)

Rougier, Regis

1999-07-01

This is a brief presentation of the technical concept developed by ALTO MAR GIRASSOL (AMG) for the Girassol umbilical and flowlines system. In 1998 AMG was awarded a contract by Elf Exploration Angola for the engineering, procurement, construction and installation (EPCI) of the umbilical and flowline system. The technical concept is based around the use of sealine bundles and self-supporting hybrid riser towers which carry the production, water injection, gas injection, gas lift and service lines. The items discussed are: (1) selected field layout, (2) seabed flowlines, hybrid riser system, umbilicals, export lines, installation plan and overall project schedule.

Identifying and evaluating high risk areas and challenges on marine drilling riser system in relation to deepwater problems

OpenAIRE

Iversen, Alexander

2012-01-01

Master's thesis in Offshore technology The main concerns during drilling operations are riser integrity and maintaining well control. This thesis has mainly been focusing on the problems and challenges faced with the marine riser system to illuminate high risk areas related to riser integrity. A marine riser system consists generally of four main elements; the upper marine riser package, riser joints, lower marine riser package, and the blowout preventer, each playing an important par...

Structural analysis of multiport riser 5A installation on tank 241SY101

Energy Technology Data Exchange (ETDEWEB)

Strehlow, J.P.

1994-09-16

The Tank 101-SY multiport riser assembly in the 241-SY-101 waste tank will replace the existing 42 inch riser with four smaller ports. Each smaller port can be used independently to access the tank interior with equipment and instruments needed to mitigate the concentration of hydrogen in the tank. This document provides a design report on the structural evaluation of the multiport riser assembly as well as its anchorage. The multiport riser assembly is a steel structure installed directly above the 42-inch riser and sealed at the existing riser flange. The assembly is structurally supported by the concrete pad placed around the 42 inch riser. The multiport riser assembly will provide two 8-inch penetrations, one 12-inch penetration and one 24-inch penetration. Each penetration will have a shielding plate. These penetrations will be used to insert equipment such as a sonic probe into the tank. In addition to normal loads, non-reactor Safety Class 1 structures, systems and components are to withstand the effects of extreme environmental loads including Design Basis Earthquake (DBE), Design Basis Wind (DBW), Design Basis Flood, Volcanic Eruptions and other abnormal loads considered on a case by case basis. Non-reactor Safety Class 2, 3 and 4 structures, systems and components are those that are not Safety Class 1 and are respectively specified as onsite safety related, occupational safety related and non-safety related items. The 241-SY-101 tank is considered as a non-reactor Safety Class 1 structure. The multiport riser assembly is considered as a non-reactor Safety Class 2 structure since it serves to contain the radioactive and toxic materials under normal operating conditions. However, the pressure relief doors provided on the assembly are considered as Safety Class 1 structures.

Flexible riser global analysis for very shallow water

OpenAIRE

Karegar, Sadjad

2013-01-01

Master's thesis in Offshore technology Flexible risers are widely used for a range of water depths and can accommodate large floater motions when using a buoyant system. A wide range of buoyancy solutions have been developed for very shallow water (e.g. 30-50 m), shallow water (e.g. 90-110 m) and semi-deep water (e.g. 300-400 m) and in the ranges between these depths. Flexible risers can have different configurations. These different solutions have different characteristics which influe...

A vivência afetiva em idosos

Directory of Open Access Journals (Sweden)

Érika Arantes de Oliveira

Full Text Available Objetivou-se analisar a vivência afetiva em idosos asilados (A e não asilados (NA a partir de dois grupos de 25 mulheres com mais de 60 anos. Utilizou-se entrevista semi-estruturada sobre história de vida e Teste de Pfister, sendo que A e NA apontaram idealização da infância e da velhice e qualificação negativa da juventude. Na fase adulta, os asilados referiram vivência mais negativa. O Pfister sinalizou, em ambos os grupos, preservação do funcionamento lógico e afetivo, mas certa ansiedade. Inexistiu diferença significativa entre A e NA, sugerindo que a institucionalização não dificulta, necessariamente, o vivenciar saudável da velhice, apontando direção para intervenções terapêuticas com esta população.

Experimental Plan for Crystal Accumulation Studies in the WTP Melter Riser

Energy Technology Data Exchange (ETDEWEB)

Miller, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-04-28

This experimental plan defines crystal settling experiments to be in support of the U.S. Department of Energy – Office of River Protection crystal tolerant glass program. The road map for development of crystal-tolerant high level waste glasses recommends that fluid dynamic modeling be used to better understand the accumulation of crystals in the melter riser and mechanisms of removal. A full-scale version of the Hanford Waste Treatment and Immobilization Plant (WTP) melter riser constructed with transparent material will be used to provide data in support of model development. The system will also provide a platform to demonstrate mitigation or recovery strategies in off-normal events where crystal accumulation impedes melter operation. Test conditions and material properties will be chosen to provide results over a variety of parameters, which can be used to guide validation experiments with the Research Scale Melter at the Pacific Northwest National Laboratory, and that will ultimately lead to the development of a process control strategy for the full scale WTP melter. The experiments described in this plan are divided into two phases. Bench scale tests will be used in Phase 1 (using the appropriate solid and fluid simulants to represent molten glass and spinel crystals) to verify the detection methods and analytical measurements prior to their use in a larger scale system. In Phase 2, a full scale, room temperature mockup of the WTP melter riser will be fabricated. The mockup will provide dynamic measurements of flow conditions, including resistance to pouring, as well as allow visual observation of crystal accumulation behavior.

Monitoring system of depressurization valves of migrated gas in annular space of flexible risers

Energy Technology Data Exchange (ETDEWEB)

Mesquita, Luiz A.; Santos, Joilson M.; Carvalho, Antonio L.; Loureiro, Patricia [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

2005-07-01

PETROBRAS Research and Development Center - CENPES developed an automatic system for monitoring pressure of annular space due to permeation of gas in flexible risers to inspect continuously integrity of such lines. To help maintaining physical integrity of flexible risers, two PSV's are installed to end fittings on top of riser, so that operation of any valve grants the maximum admissible gas pressure within the riser annular space, as overpressure might cause damages to external polymeric layer of flexible riser. Due to the fact that there is no mechanism allowing operation to verify correct PSV performance and frequency of valve's closings and openings, we felt to be necessary the development and implement an automatic instrumented system, integrated to platform's automation and control infrastructure. The objective of this instrumentation is to monitor and register pressure of annular space in flexible riser, as well as XV's depressurization frequency. Having such information registered and monitored, can infer some riser structural conditions, anticipating repairs and preventive maintenance. In this paper we present developed system details including instruments required, application, operation of associated screens that are used in the ECOS, with events, alarms and industrial automation services required (Application development and system integration). (author)

Proximal tibial fracture following anterior cruciate ligament reconstruction surgery: a biomechanical analysis of the tibial tunnel as a stress riser.

Science.gov (United States)

Aldebeyan, Wassim; Liddell, Antony; Steffen, Thomas; Beckman, Lorne; Martineau, Paul A

2017-08-01

This is the first biomechanical study to examine the potential stress riser effect of the tibial tunnel or tunnels after ACL reconstruction surgery. In keeping with literature, the primary hypothesis tested in this study was that the tibial tunnel acts as a stress riser for fracture propagation. Secondary hypotheses were that the stress riser effect increases with the size of the tunnel (8 vs. 10 mm), the orientation of the tunnel [standard (STT) vs. modified transtibial (MTT)], and with the number of tunnels (1 vs. 2). Tibial tunnels simulating both single bundle hamstring graft (8 mm) and bone-patellar tendon-bone graft (10 mm) either STT or MTT position, as well as tunnels simulating double bundle (DB) ACL reconstruction (7, 6 mm), were drilled in fourth-generation saw bones. These five experimental groups and a control group consisting of native saw bones without tunnels were loaded to failure on a Materials Testing System to simulate tibial plateau fracture. There were no statistically significant differences in peak load to failure between any of the groups, including the control group. The fracture occurred through the tibial tunnel in 100 % of the MTT tunnels (8 and 10 mm) and 80 % of the DB tunnels specimens; however, the fractures never (0 %) occurred through the tibial tunnel of the standard tunnels (8 or 10 mm) (P = 0.032). In the biomechanical model, the tibial tunnel does not appear to be a stress riser for fracture propagation, despite suggestions to the contrary in the literature. Use of a standard, more vertical tunnel decreases the risk of ACL graft compromise in the event of a fracture. This may help to inform surgical decision making on ACL reconstruction technique.

Riser equipment decontamination engineering task plan; TOPICAL

International Nuclear Information System (INIS)

BOGER, R.M.

1999-01-01

On October 15, 1998, two Characterization Project Operations (CPO) employees were found to have contaminated clothing. An operator had 300,000-dpm/100cm2 beta/gamma, no alpha, contamination on his coat sleeve and a Radiation Control Technician (RCT) had 10,000 dpm/100cm2 beta/gamma, no alpha, on his shirt sleeve. The CPO swing shift crew was working in TX tank farm, performing sampling activities at 241-TX-113. TX tank farm is a ''clean farm'' and does not require anti-contamination clothing for entry. The CPO personnel were dressed in normal work clothes. An operator and an RCT were performing a pre-job survey that involved removing bagging around the riser equipment. When the RCT saw that the contamination readings from smear samples of the riser equipment were greater than expected, the job was suspended. Crew members were then directed to areas of lower background radiation for personnel surveys. During personnel surveys, reportable contamination was found on the coat sleeve of the operator who had been involved in the pre-job survey and on the shirt sleeve of the RCT who had been involved in the pre-job survey. No other personnel were found to be contaminated. Because of this off normal event Characterization Engineering was given the following corrective action: Examine the process methodology used for core sampling operations to determine practicality and potential long-term advantages of reducing personnel contact with contaminated equipment. This Engineering Task Plan ensures that LMHC 1998a, Corrective Action No.7 is completely addressed by Characterization Engineering. The deliverable is an Engineering Study that evaluates decontamination of riser equipment components and considers additional engineered features to reduce potential exposure to workers operating the riser equipment. This engineering study shall also address any released design features that have failed to be implemented

An efficient structural finite element for inextensible flexible risers

Science.gov (United States)

Papathanasiou, T. K.; Markolefas, S.; Khazaeinejad, P.; Bahai, H.

2017-12-01

A core part of all numerical models used for flexible riser analysis is the structural component representing the main body of the riser as a slender beam. Loads acting on this structural element are self-weight, buoyant and hydrodynamic forces, internal pressure and others. A structural finite element for an inextensible riser with a point-wise enforcement of the inextensibility constrain is presented. In particular, the inextensibility constraint is applied only at the nodes of the meshed arc length parameter. Among the virtues of the proposed approach is the flexibility in the application of boundary conditions and the easy incorporation of dissipative forces. Several attributes of the proposed finite element scheme are analysed and computation times for the solution of some simplified examples are discussed. Future developments aim at the appropriate implementation of material and geometric parameters for the beam model, i.e. flexural and torsional rigidity.

OTEC riser cable model and prototype testing

Science.gov (United States)

Kurt, J. P.; Schultz, J. A.; Roblee, L. H. S.

1981-12-01

Two different OTEC riser cables have been developed to span the distance between a floating OTEC power plant and the ocean floor. The major design concerns for a riser cable in the dynamic OTEC environment are fatigue, corrosion, and electrical/mechanical aging of the cable components. The basic properties of the cable materials were studied through tests on model cables and on samples of cable materials. Full-scale prototype cables were manufactured and were tested to measure their electrical and mechanical properties and performance. The full-scale testing was culminated by the electrical/mechanical fatigue test, which exposes full-scale cables to simultaneous tension, bending and electrical loads, all in a natural seawater environment.

Magnetic non-destructive evaluation of ruptures of tensile armor in oil risers

International Nuclear Information System (INIS)

Pérez-Benitez, J A; Padovese, L R

2012-01-01

Risers are flexible multilayered pipes formed by an inner flexible metal structure surrounded by polymer layers and spiral wound steel ligaments, also known as armor wires. Since these risers are used to link subsea pipelines to floating oil and gas production installations, and their failure could produce catastrophic consequences, some methods have been proposed to monitor the armor integrity. However, until now there is no practical method that allows the automatic non-destructive detection of individual armor wire rupture. In this work we show a method using magnetic Barkhausen noise that has shown high efficiency in the detection of armor wire rupture. The results are examined under the cyclic and static load conditions of the riser. This work also analyzes the theory behind the singular dependence of the magnetic Barkhausen noise on the applied tension in riser armor wires. (paper)

An analytic solution of the static problem of inclined risers conveying fluid

KAUST Repository

Alfosail, Feras; Nayfeh, Ali H.; Younis, Mohammad I.

2016-01-01

We use the method of matched asymptotic expansion to develop an analytic solution to the static problem of clamped–clamped inclined risers conveying fluid. The inclined riser is modeled as an Euler–Bernoulli beam taking into account its self

Most recent developments for monitoring and controlling the annulus conditions of Marlim-Sul flexible risers

Energy Technology Data Exchange (ETDEWEB)

Rabelo, Alexandre S.; Motta, Antonio; Romero, Antonio; Nunes, Joao P.; Zaganelli Junior, Jose L.; Brack, Marcelo [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2009-07-01

The main objective of this paper is to present the recent developments for monitoring and controlling the annulus conditions of flexible risers. PETROBRAS has been monitoring the pressure of permeated gas in the annulus region of some risers in order to infer the eventual occurrence of non-conformities as damage on the riser external sheath, for example. Such occurrence would affect the permeated gas flow pattern, the gas pressurization period and the relief valve opening frequencies. Furthermore, the mentioned occurrence would increase the susceptibility of the steel armors to experience the potential failure mechanism of corrosion. In PETROBRAS, the current monitoring method is characterized by visual and periodic manometer readings from a manometer set installed near each riser end-fitting. The data is recorded in a daily report and analyzed by personnel onshore, who are in charge of comparing data and requesting relief valve's actuation, whenever necessary. The paper illustrates Marlim-Sul Asset experience on monitoring and data processing to control the annulus conditions of flexible risers during operation. It presents the in-house developed methodology to data management and processing. This methodology is based on a daily analysis of the permeated gas data worksheet. Some examples are given to illustrate it. The paper also summarizes current developments, in progress, in order to improve riser integrity management. The first development is being done to implement, in the future, automatic data acquisition and control systems. The purpose of automating this process is to improve methods and techniques for data acquisition, transmission and processing. The second development focuses on applications in which riser top end-fittings are submerged. In this particular scenario, a special system - with a quick connection sub sea device - is under development to allow the connection, by divers, after the riser pull-in, of the riser annulus to the platform gas

Tools for in service monitoring and testing of riser to prevent failure and extend service life

Energy Technology Data Exchange (ETDEWEB)

Ward, Haakon; Bondevik, Jon Olav; Skjerve, Haavard; Tveit, Oeyvind [SeaFlex AS, Asker (Norway)

2005-07-01

Exploration and development of new oil and gas fields is heavily dependant on use of flexible pipes and many field developments would not have been possible without them. The number of flexible risers in service is constantly increasing since relatively few offshore projects have reached the estimated operational life and the operational lifetime of several fields in-service has been extended due to new and improved technology. Many risers have been in service over a large number of years. Some risers have been operated under demanding conditions such as severe dynamic loads, high pressure and temperatures. One may in some cases find that risers actually have shorter service life than estimated in the design phase due to the severe operational conditions. In order to extend the use of the riser, some risers may have to be modified and re-terminated and prepared for a new and less demanding application. In order to operate risers safely, it is important to re-assess the fatigue life in order to prevent potential riser failure. The operator should implement methods and tools for in-service monitoring and testing. This paper addresses efficient and reliable methods and tools for monitoring of critical operational parameters as well as in-service riser testing. A brief description of structural failure modes will also be given in order to understand how to interpret test results in view of potential failure modes. (author)

Numerical simulation of thermal-hydraulic processes in the riser chamber of installation for clinker production

Directory of Open Access Journals (Sweden)

Borsuk Grzegorz

2016-03-01

Full Text Available Clinker burning process has a decisive influence on energy consumption and the cost of cement production. A new problem is to use the process of decarbonization of alternative fuels from waste. These issues are particularly important in the introduction of a two-stage combustion of fuel in a rotary kiln without the typical reactor-decarbonizator. This work presents results of numerical studies on thermal-hydraulic phenomena in the riser chamber, which will be designed to burn fuel in the system where combustion air is supplied separately from the clinker cooler. The mathematical model is based on a combination of two methods of motion description: Euler description for the gas phase and Lagrange description for particles. Heat transfer between particles of raw material and gas was added to the numerical calculations. The main aim of the research was finding the correct fractional distribution of particles. For assumed particle distribution on the first stage of work, authors noted that all particles were carried away by the upper outlet to the preheater tower, what is not corresponding to the results of experimental studies. The obtained results of calculations can be the basis for further optimization of the design and operating conditions in the riser chamber with the implementation of the system.

Development and characterization of composite materials for production of composite risers by filament winding

Directory of Open Access Journals (Sweden)

Ledjane Lima Sobrinho

2011-09-01

Full Text Available Industry has been challenged to provide riser systems which are more cost effective and which can fill the technology gaps with respect to water depth, riser diameter and high temperatures left open by flexibles, steel catenary risers (SCRs and hybrid risers. Composite materials present advantages over conventional steel risers because composite materials are lighter, more fatigue and corrosion resistant, better thermal insulators and can be designed for improving the structural and mechanical response. This paper contains a study of the toughening mechanism of an epoxy resin under rubber addition by means of fractographic analysis and its relation with the fracture process and increase of strength of a composite riser employing this polymeric matrix. Initially, an epoxy resin system was toughened by rubber CTBN addition (10 wt. (% as a way of improving the flexibility of future risers. Mechanical and thermal analyses were carried out for characterizing the polymeric systems. Later, composite tubes were prepared and mechanically characterized. The influence of matrix toughening on the mechanical behavior of the tubes was also studied. Split-disk tests were used to determine the hoop tensile strength of these specimens. The results indicate that the matrix plays an important role in composite fracture processes. The adding rubber to the polymeric matrix promoted a simultaneous increase of stress and elongation at fracture of the tubes manufactured herein, which is not often reported. These results, probably, is function of better adhesion between fibers and polymeric matrix observed in the CTBN-modified composite rings, which was evidenced in the fractografic analysis by SEM after the split-disk tests.

Violência institucional: vivências no cotidiano da equipe de enfermagem

Directory of Open Access Journals (Sweden)

Ana Maria Ribeiro dos Santos

2011-02-01

Full Text Available Estudo qualitativo que objetivou descrever a vivência dos profissionais da equipe de enfermagem expostos à violência institucional, discutir como essas vivências influem no cotidiano e na organização do serviço e conhecer os eventos causadores dessas atitudes violentas. Os sujeitos foram onze profissionais da equipe de enfermagem. Os dados foram produzidos por meio de entrevista, analisados utilizando técnica de análise temática, organizados nas categorias: vivências de violência na equipe de enfermagem, influência da violência no cotidiano de trabalho e na organização do serviço e fatores causadores de atitudes violentas contra a equipe de enfermagem. Os resultados demonstram que os profissionais encontram-se susceptíveis a atitudes violentas no ambiente de trabalho por permanecerem mais tempo e em maior interação com pacientes e acompanhantes

Violência institucional: vivências no cotidiano da equipe de enfermagem

Directory of Open Access Journals (Sweden)

Ana Maria Ribeiro dos Santos

Full Text Available Estudo qualitativo que objetivou descrever a vivência dos profissionais da equipe de enfermagem expostos à violência institucional, discutir como essas vivências influem no cotidiano e na organização do serviço e conhecer os eventos causadores dessas atitudes violentas. Os sujeitos foram onze profissionais da equipe de enfermagem. Os dados foram produzidos por meio de entrevista, analisados utilizando técnica de análise temática, organizados nas categorias: vivências de violência na equipe de enfermagem, influência da violência no cotidiano de trabalho e na organização do serviço e fatores causadores de atitudes violentas contra a equipe de enfermagem. Os resultados demonstram que os profissionais encontram-se susceptíveis a atitudes violentas no ambiente de trabalho por permanecerem mais tempo e em maior interação com pacientes e acompanhantes

An optical sensor for the detection of leaks from subsea pipelines and risers

International Nuclear Information System (INIS)

McStay, D; Kerlin, J; Acheson, R

2007-01-01

An optical sensor for the rapid detection of detect leaks of oil, hydraulic fluids or leak detection chemicals from underwater pipelines and risers is reported. The sensor is designed to be deployed on ROVs or AUVs for the rapid survey of underwater pipelines and risers. The system employs ultra-bright LEDs to project a sensing light beam into the water to allow real time detection of ppm concentration plumes of material leaking from pipelines or riser in real time. Typically the system is deployed on an ROV which inspects a pipeline at a height of 2-3m

Singing mitigation in an export riser via liquid injection: a field case study

NARCIS (Netherlands)

Belfroid, S.P.C.; Korst, H.J.C.; Beek, P.J.G. van; Lunde, K.; Eidsvik, I.G.; Hansen, F.; Olsen, B.

2014-01-01

Flexible Risers are prone to the generation of high amplitude tonal noise, i.e. a so-called singing riser. Recently, severe vibrations and high noise levels were encountered on the turret of an FPSO in the Norwegian Sea, resulting in significantly reduced production. The vibrations could be

The Sleipner riser platform experience

International Nuclear Information System (INIS)

Anon.

1993-01-01

The article discusses briefly the Norwegian Sleipner riser project. The project has provided new insight on how to handle smaller development projects in a time saving and cost effective way. Through active cooperation between the prime contractors, the total project time, which included engineering, fabrication ready to tow, was slashed to a record 11 months. Normally, such a project would take a couple of years to complete. 1 fig

Relatos de vivências educacionais

Directory of Open Access Journals (Sweden)

Congresso Internacional de Dislexia

2011-05-01

Full Text Available Relatos de experiências em educação, abrangendo a descrição de projeto ou vivência específica em sala de aula ou outro ambiente educacional, que envolva o trabalho com escolares com dislexia e outros transtornos da aprendizagem da leitura e escrita.Os trabalhos foram apresentados na terceira edição do Congresso Internacional de Dislexia (CID, realizado nas dependências do Centro Universitário Metodista Izabela Hendrix, em maio de 2011. 

Inspection and monitoring techniques for un-bonded flexible risers and pipelines

OpenAIRE

Simonsen, Anders

2014-01-01

Master's thesis in Offshore technology Un-bonded flexible pipelines and risers are an alternative to conventional rigid steel pipes. The use of flexible pipes has enabled development of several offshore fields that seemed unfeasible with the use of rigid pipes due to extensive seabed preparation and large dynamic motions. The lack of knowledge and integrity management tools for flexible pipes is a limiting factor and cause pipelines and risers to be replaced before their service life has ...

Flow Mapping in a Gas-Solid Riser via Computer Automated Radioactive Particle Tracking (CARPT)

Energy Technology Data Exchange (ETDEWEB)

Muthanna Al-Dahhan; Milorad P. Dudukovic; Satish Bhusarapu; Timothy J. O' hern; Steven Trujillo; Michael R. Prairie

2005-06-04

Statement of the Problem: Developing and disseminating a general and experimentally validated model for turbulent multiphase fluid dynamics suitable for engineering design purposes in industrial scale applications of riser reactors and pneumatic conveying, require collecting reliable data on solids trajectories, velocities ? averaged and instantaneous, solids holdup distribution and solids fluxes in the riser as a function of operating conditions. Such data are currently not available on the same system. Multiphase Fluid Dynamics Research Consortium (MFDRC) was established to address these issues on a chosen example of circulating fluidized bed (CFB) reactor, which is widely used in petroleum and chemical industry including coal combustion. This project addresses the problem of lacking reliable data to advance CFB technology. Project Objectives: The objective of this project is to advance the understanding of the solids flow pattern and mixing in a well-developed flow region of a gas-solid riser, operated at different gas flow rates and solids loading using the state-of-the-art non-intrusive measurements. This work creates an insight and reliable database for local solids fluid-dynamic quantities in a pilot-plant scale CFB, which can then be used to validate/develop phenomenological models for the riser. This study also attempts to provide benchmark data for validation of Computational Fluid Dynamic (CFD) codes and their current closures. Technical Approach: Non-Invasive Computer Automated Radioactive Particle Tracking (CARPT) technique provides complete Eulerian solids flow field (time average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy, and eddy diffusivities). It also gives directly the Lagrangian information of solids flow and yields the true solids residence time distribution (RTD). Another radiation based technique, Computed Tomography (CT) yields detailed time averaged local holdup profiles at

Development of Millimeter-Wave Velocimetry and Acoustic Time-of-Flight Tomography for Measurements in Densely Loaded Gas-Solid Riser Flow

Energy Technology Data Exchange (ETDEWEB)

Fort, James A.; Pfund, David M.; Sheen, David M.; Pappas, Richard A.; Morgen, Gerald P.

2007-04-01

The MFDRC was formed in 1998 to advance the state-of-the-art in simulating multiphase turbulent flows by developing advanced computational models for gas-solid flows that are experimentally validated over a wide range of industrially relevant conditions. The goal was to transfer the resulting validated models to interested US commercial CFD software vendors, who would then propagate the models as part of new code versions to their customers in the US chemical industry. Since the lack of detailed data sets at industrially relevant conditions is the major roadblock to developing and validating multiphase turbulence models, a significant component of the work involved flow measurements on an industrial-scale riser contributed by Westinghouse, which was subsequently installed at SNL. Model comparisons were performed against these datasets by LANL. A parallel Office of Industrial Technology (OIT) project within the consortium made similar comparisons between riser measurements and models at NETL. Measured flow quantities of interest included volume fraction, velocity, and velocity-fluctuation profiles for both gas and solid phases at various locations in the riser. Some additional techniques were required for these measurements beyond what was currently available. PNNL’s role on the project was to work with the SNL experimental team to develop and test two new measurement techniques, acoustic tomography and millimeter-wave velocimetry. Acoustic tomography is a promising technique for gas-solid flow measurements in risers and PNNL has substantial related experience in this area. PNNL is also active in developing millimeter wave imaging techniques, and this technology presents an additional approach to make desired measurements. PNNL supported the advanced diagnostics development part of this project by evaluating these techniques and then by adapting and developing the selected technology to bulk gas-solids flows and by implementing them for testing in the SNL riser

An experimental study on the key fretting variables for flexible marine risers

OpenAIRE

O’Halloran, S.M.; Harte, A.M.; Shipway, P.H.; Leen, S.B.

2018-01-01

This paper presents an experimental investigation into the effects of contact conformity, contact pressure and displacement amplitude on the gross-slip fretting behaviour grease-lubricated cylinder-on-flat contacts in the context of flexible marine riser pressure armour wire, and compares behaviour with that observed in unlubricated conditions. Characterisation of friction and wear is critical to fretting fatigue life prediction in flexible risers since friction directly controls trailing-edg...

Fluid dynamics characterization of riser in a FCC cold flow model using gas radiotracer

International Nuclear Information System (INIS)

Santos, Valdemir A. dos; Lima, Emerson A.O.

2013-01-01

Was carried out the characterization of a diameter small riser of a cold flow model of a circulating fluidized bed (CFB), with aid of a radioactive tracer. Compressed air and catalytic cracking of petroleum flow through solids pneumatic transport regime, made of transparent material (glass, acrylic, PVC, polycarbonate) for study of problems in Fluid Catalytic Cracking (FCC) unit and development of methods of measurement of fluid dynamic parameters. The CFB model consisted of a mixer component solid-gas (compressed air at 25 deg C and 200 kN/m 2 ; cracking catalyst with an average diameter of 72μm and specific mass of 1,500 kg/m 3 ), comprising a riser pipe glass 0.02m internal diameter and 1.8m height, a gas solid separation vessel by flash effect, with the filter in the gas outlet, and a return column (a glass tube with an internal diameter of 0.0254m) to redirect the catalyst for the riser base. Recorded data allowed studies on residence time distribution of the gaseous phase in the riser, with the identification and characterization of the flow of gas-solid components in the CFB riser of small diameter. A plug flow type with deviations due to back mixing of catalyst close to the walls, associated with the density difference between this component was observed. (author)

Recreating Riser Slugging Flow Based on an Economic Lab-sized Setup

DEFF Research Database (Denmark)

Hansen, Lasse; Pedersen, Simon; Yang, Zhenyu

2013-01-01

As a kind of periodic phenomenon, the slugging flow in the offshore oil & gas production addresses a lot of attentions, due to its limitation of production rate, periodic overload processing facilities, and even direct cause of emergent shutdown. This work studies the emulation of the riser...... slugging flow in the offshore oil & gas production, by constructing an economical lab-sized setup in the university campus. Firstly, the construction and used components for the lab setup are illustrated; then, the constructed setup is validated by checking the consistency with some existing typical riser...

Analysis of the effects of corrosion probe on riser 241-AN-102-WST-16 during seismic event

International Nuclear Information System (INIS)

ZIADA, H.H.

1998-01-01

This analysis supports the installation activity of the corrosion probe in Tank 241-AN-102. The probe is scheduled to be installed in Riser 241-AN-102-WST-16 (formerly known as Riser 15B). The purpose of this analysis is to evaluate the potential effect of the corrosion probe on the riser during a credible seismic event. The previous analysis (HNF 1997a) considered only pump jet impingement loading

Fatigue Strength of Titanium Risers - Defect Sensitivity

Energy Technology Data Exchange (ETDEWEB)

Babalola, Olusegun Tunde

2001-07-01

This study is centred on assessment of the fatigue strength of titanium fusion welds for deep-water riser's applications. Deep-water risers are subjected to significant fatigue loading. Relevant fatigue data for titanium fusion welds are very scarce. Hence there is a need for fatigue data and life prediction models for such weldments. The study has covered three topics: Fatigue testing, Fractography and defect assessment, and Fracture Mechanics modelling of fatigue crack growth. Two series of welded grade of titanium consisting of 14 specimens in each series were fatigue tested under constant amplitude loading. Prior to fatigue testing, strain gauge measurements of some specimens was conducted to enable the definition of stress range in the fatigue assessment procedure. The results were compared with finite solid element analysis and related to fatigue stresses in a riser pipe wall. Distribution and geometry of internal and surface defects both in the as-welded and in the post-weld machined conditions were assessed using fractography. This served as a tool to determine the fatigue initiation point in the welds. Fracture mechanics was applied to model fatigue strength of titanium welds with initiation from weld defects. Two different stress intensity factor formulations for embedded eccentrically placed cracks were used for analysis of elliptical cracks with the major axis parallel and close to one of the free surfaces. The methods were combined to give a satisfactory model for crack growth analysis. The model analyses crack growth of elliptical and semi-elliptical cracks in two directions, with updating of the crack geometry. Fatigue strength assessment was conducted using two crack growth models, the Paris-Erdogan relation with no threshold and the Donahue et al. relation with an implied threshold. The model was validated against experimental data, with a discussion on the choice of crack growth model. (author)

Single-shell tank riser resistance to ground test plan

International Nuclear Information System (INIS)

Kiewert, L.R.

1996-01-01

This Test Procedure provides the general directions for conducting Single-Shell Tank Riser to Earth Measurements which will be used by engineering as a step towards providing closure for the Lightning Hazard Issue

Numerical simulation and experimental analysis for a Risers Uphold Sub-Surface Buoy (BSR); Simulacao numerica e ensaio experimental da Boia de Sub-superficie de Suporte de Risers - BSSR

Energy Technology Data Exchange (ETDEWEB)

Araujo, Jairo B. de; Almeida, Jose Carlos L. de [PETROBRAS, Rio de Janeiro, RJ (Brazil); Rangel, Marcos; Fernandes, Antonio C.; Santos, Melquisedec F. dos; Sales Junior, Joel Sena [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE)

2004-07-01

This paper presents results, numeric and experimental, due to installation operation of a Risers Uphold Sub-Surface Buoy, (BSR). This kind of installation developed by PETROBRAS is unique in the world. The work of BSR installation was based on a numeric pre analysis to verify the system and determine the main parameters to be experimentally verified. The second phase of the work was the experimental analysis in a deep water ocean basin. s. The work describes the BSR and their main accessories, the experimental environment and the model constructed in aluminum in a 1:12 scale and the main results. (author)

Remote installation of risers on underground nuclear waste storage tanks

International Nuclear Information System (INIS)

Jackson, J.P.; Gessner, R.F.

1988-03-01

The West Valley Demonstration Project was established to solidify 2120 m 3 (560,000) gallons of high-level nuclear waste generated during six years of commercial nuclear fuel reprocessing. This liquid will be processed to remove radioactive elements which, with the remaining sludge, will be combined with glass formers and be converted into borosilicate glass. Risers were installed on the high-level tank for installation of pumps which will be used to remove the liquid and sludge. The extensive use of remote technology was required to install the risers and to minimize operator exposure to high levels of radiation and contamination. The riser installation required remotely: drilling through two feet of concrete shielding; installing pump access pipes which are welded to the tank top; and cutting holes in tanks located 3658 mm (12) feet below ground. These operations were successfully completed 13 times without exposing personnel to high-level radiation or contamination. Specially designed remote equipment was developed for each step of this operation. Extensive operator training in the use of this equipment was performed on a tank with low radiation prior to work on the high-level tank. This paper discusses the application of remote technology that assured a quality job was safely accomplished. 3 refs., 18 figs., 2 tabs

Dalia integrated production bundle (IPB): an innovative riser solution for deep water fields

Energy Technology Data Exchange (ETDEWEB)

Reals, Th Boscals de; Gloaguen, M.; Roche, F. [Total E and P (Angola); Marion, A.; Poincheval, A. [Technip, Paris (France)

2008-07-01

The Dalia field is located 210 km north west of Luanda (Angola), about 140 km from shore in 1400 meter water-depth. It was the second major discovery out of 15 made in the block 17 operated by Total. The Dalia Umbilical, Flow lines and Risers EPCI Contract was awarded in 2003. The sea-line network to connect and control the 71 wells and 9 manifolds consist of the following: 40 km of insulated pipe in pipe (12 inches into 17 inches) production flow lines; 45 km of 12 inches water and gas injection lines; 6 off 1.7 km flexible water and gas injection risers; 8 off 1.65 km flexible Integrated Production Bundle (IPB) risers; 75 km of control umbilicals. The flow assurance and associated insulation requirement of the production transport system was one of the main challenges of the project. With a crude temperature of 45 deg C at the wellhead and the required minimum temperature of 35 deg C on arrival at the FPSO, this problem was complex. Understanding that, due to the Joule Thompson effect of the riser gas lift, a 'built in' loss of about 5 deg C is induced and together with further losses through the sub sea pipelines, some up to 6 km long, the agreed solution was 'pipe in pipe' for the production flow lines. The innovative flexible IPB riser, incorporating gas lift and heating to keep the fluid temperature above hydrate formation zone, was the selected riser solution. The IPB is new technology for deep water, developed by Technip for Dalia, and consists of a 12 inches nominal central flexible, surrounded by layers of heat tracing cables, small bore gas lift lines, optical fibres and many insulation layers with an Overall Heat Transfer Coefficient of approximately 3,4 W/m{sup 2}K. After an earlier research and development programme, a further extensive qualification programme was conducted during the course of the project, culminating with the deep water testing phase offshore Brazil. The IPB was then approved for fabrication and installation

Validation Plan of Turbulence Models for Internal Gas Flow Analysis in a Heated Rectangular Riser Duct

Energy Technology Data Exchange (ETDEWEB)

Kim, Sin-Yeob; Shin, Dong-Ho; Park, Goon-Cherl; Cho, Hyoung Kyu [Seoul National Univ., Seoul (Korea, Republic of); Kim, Chan-Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

VHTR being developed at Korea Atomic Energy Research Institute adopts an air-cooled Reactor Cavity Cooling System (RCCS) incorporating rectangular riser channels to remove the afterheat emitted from the reactor vessel. Because the performance of RCCS is determined by heat removal rate through the RCCS riser, it is important to understand the heat transfer phenomena in the RCCS riser to ensure the safety of the reactor. In the mixed convection, due to the buoyance force induced by temperature and density differences, local flow structure and heat transfer mode near the heated wall have significantly dissimilar characteristics from both forced convection and free convection. In this study, benchmark calculation was conducted to reproduce the previous statements that V2F turbulence model can capture the mixed convection phenomena with the Shehata's experimental data. Then, the necessity of the model validation for the mixed convection phenomena was confirmed with the CFD analyses for the geometry of the prototype RCCS riser. For the purpose of validating the turbulence models for mixed convection phenomena in the heated rectangular riser duct, validation plan with three experimental tests was introduced. Among them, the flow visualization test facility with preserved cross-section geometry was introduced and a preliminary test result was shown.

Model of a catalytic injection in a riser by means of gamma ray transmission measurements

Energy Technology Data Exchange (ETDEWEB)

Moura, Alex E.; Brito, Macio F.P.; Dantas, Carlos C.; Melo, Silvio B., E-mail: alex.emoura@ufpe.br, E-mail: sbm@ufpe.br [Universidade Federal de Pernambuco (DEN/UFPE), Recife, PE (Brazil); Barbosa, Enivaldo S., E-mail: Enivaldo.santos@ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia Mecanica; Lima, Emerson A.O., E-mail: eal@poli.br [Universidade de Pernambuco, Recife, PE (Brazil). Departamento de Matematica

2015-07-01

In Gas solid process involving a solid circulation through a closed loop the knowledge of the Solids Circulation Rate (SCR) is fundamental to control and improve the operation of a circulating fluidized bed system. A valve controls the circulation rate of solids in the riser of a fluid catalytic cracking unit. Initially, to control the catalyst injection in the riser, a rotary valve controlled and measured solid flow injection, but with a limited working time. Due to the fine powder catalyst abrasive action on the valve steel axis, this device stop work. A lab made valve were design to avoiding direct contact of the catalyst with mechanical moving parts in while control solid injection in riser, but do not measure the solid flow like the rotary valve. To control the lab made device a fixed pressure measurement at riser bottom is provided by control setup which corresponds to a given mass/time solid injection. In the present work, we proposed a method to evaluate the control valve based on a non-invasive technique. With gamma ray transmission measurements, in a cross section of the pipe, we developed a model that was used in the control system of the Cold Pilot Unit (CPU). Therefore, the interaction of the gamma ray with solid flow in riser should yield the necessary information for the process control system. A first model approximation consider the solid flow rate injection and solid velocity in riser as proposed in literature. In the CPU control system a Programmable Logic Controller-PLC keeps steady state processing the airflow, pressure profile and solid flow inputs. Additionally to preexisting PLC platform, some LabVIEW algorithms were implemented to achieve a good system performance operational condition. (author)

Model of a catalytic injection in a riser by means of gamma ray transmission measurements

International Nuclear Information System (INIS)

Moura, Alex E.; Brito, Macio F.P.; Dantas, Carlos C.; Melo, Silvio B.; Barbosa, Enivaldo S.; Lima, Emerson A.O.

2015-01-01

In Gas solid process involving a solid circulation through a closed loop the knowledge of the Solids Circulation Rate (SCR) is fundamental to control and improve the operation of a circulating fluidized bed system. A valve controls the circulation rate of solids in the riser of a fluid catalytic cracking unit. Initially, to control the catalyst injection in the riser, a rotary valve controlled and measured solid flow injection, but with a limited working time. Due to the fine powder catalyst abrasive action on the valve steel axis, this device stop work. A lab made valve were design to avoiding direct contact of the catalyst with mechanical moving parts in while control solid injection in riser, but do not measure the solid flow like the rotary valve. To control the lab made device a fixed pressure measurement at riser bottom is provided by control setup which corresponds to a given mass/time solid injection. In the present work, we proposed a method to evaluate the control valve based on a non-invasive technique. With gamma ray transmission measurements, in a cross section of the pipe, we developed a model that was used in the control system of the Cold Pilot Unit (CPU). Therefore, the interaction of the gamma ray with solid flow in riser should yield the necessary information for the process control system. A first model approximation consider the solid flow rate injection and solid velocity in riser as proposed in literature. In the CPU control system a Programmable Logic Controller-PLC keeps steady state processing the airflow, pressure profile and solid flow inputs. Additionally to preexisting PLC platform, some LabVIEW algorithms were implemented to achieve a good system performance operational condition. (author)

Development of an environment for 3D visualization of riser dynamics

Energy Technology Data Exchange (ETDEWEB)

Bernardes Junior, Joao Luiz; Martins, Clovis de Arruda [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica]. E-mails: joao.bernardes@poli.usp.br; cmartins@usp.br

2006-07-01

This paper describes the merging of Virtual Reality and Scientific Visualization techniques in the development of Riser View, a multi platform 3D environment for real time, interactive visualization of riser dynamics. Its features, architecture, unusual collision detection algorithm and how up was customized for the project are discussed. Using Open GL through VRK, the software is able to make use of the resources available in most modern Graphics. Acceleration Hardware to improve performance. IUP/LED allows for native loo-and-feel in MS-Windows or Linux platform. The paper discusses conflicts that arise between scientific visualization and aspects such as realism and immersion, and how the visualization is prioritized. (author)

Application of corrosion screening tools for riser inspection

International Nuclear Information System (INIS)

Zamir Mohamed Daud; Vijayan, S.

2003-01-01

As offshore facilities approach the end of their design life, owners would like to assess the condition and integrity of plant and equipment. Detailed inspection, including non-destructive testing (NDT), are implemented and results are utilised for predictive maintenance and estimating useful remaining life. Except for risk based inspection, the extent of surface coverage required would be more compared to inspection of pre-determined spots. Risers, for example, usually have several layers of coating that prevent use of conventional techniques for inspection of corrosion. Complete coverage requires access (including removal coatings and insulation). Inspection utilising the conventional NDT tools can be very slow and expensive. However, recent advances have forwarded the use of specialised NDT techniques that were developed for inspection of corrosion under insulation (CUI). This paper details two screening inspection tools, LIXI Profiler and RTD-INCOTEST that have been applied to inspection of risers. LIXI Profiler is based on attenuation of penetrating radiation by materials, and RTD-INCOTEST is based on decay of pulsed eddy current in materials. (Author)

New tools for steel catenary risers inspection; Novas ferramentas para inspecao de risers tipo SCR

Energy Technology Data Exchange (ETDEWEB)

Camerini, Claudio Soligo; Marinho, Carla Alves; Raphael, Fabiana N.; Maia, Carlos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Freitas, Miguel [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil); Lopes, Ricardo Tadeu; Rocha, Henrique [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

2005-07-01

The Research Center of PETROBRAS and two of the Federal Brazilian Universities, PUC-Rio and UFRJ, have been developing two new projects in order to inspect risers of petroleum production. The first tool is an instrumented pig for profiling internal corrosion, having flexibility under diameter variations and independence related to thickness wall pipeline. The second one is a gammagraphy system remotely operated by ROVs, to be employed in alveoli corrosion and fatigue cracks detection in underwater pipelines. This work shows the trajectory of these two tools, describing laboratory and field tests and the future activities. (author)

Effect of bidirectional internal flow on fluid–structure interaction dynamics of conveying marine riser model subject to shear current

Directory of Open Access Journals (Sweden)

Zheng-Shou Chen

2012-03-01

Full Text Available This article presents a numerical investigation concerning the effect of two kinds of axially progressing internal flows (namely, upward and downward on fluid–structure interaction (FSI dynamics about a marine riser model which is subject to external shear current. The CAE technology behind the current research is a proposed FSI solution, which combines structural analysis software with CFD technology together. Efficiency validation for the CFD software was carried out first. It has been proved that the result from numerical simulations agrees well with the observation from relating model test cases in which the fluidity of internal flow is ignorable. After verifying the numerical code accuracy, simulations are conducted to study the vibration response that attributes to the internal progressive flow. It is found that the existence of internal flow does play an important role in determining the vibration mode (/dominant frequency and the magnitude of instantaneous vibration amplitude. Since asymmetric curvature along the riser span emerges in the case of external shear current, the centrifugal and Coriolis accelerations owing to up- and downward internal progressive flows play different roles in determining the fluid–structure interaction response. The discrepancy between them becomes distinct, when the velocity ratio of internal flow against external shear current is relatively high.

Wake reconfiguration downstream of an inclined flexible cylinder at the onset of vortex-induced vibrations

Science.gov (United States)

Bourguet, Remi; Triantafyllou, Michael

2016-11-01

Slender flexible cylinders immersed in flow are common in nature (e.g. plants and trees in wind) and in engineering applications, for example in the domain of offshore engineering, where risers and mooring lines are exposed to ocean currents. Vortex-induced vibrations (VIV) naturally develop when the cylinder is placed at normal incidence but they also appear when the body is inclined in the current, including at large angles. In a previous work concerning a flexible cylinder inclined at 80 degrees, we found that the occurrence of VIV is associated with a profound alteration of the flow dynamics: the wake exhibits a slanted vortex shedding pattern in the absence of vibration, while the vortices are shed parallel to the body once the large-amplitude VIV regime is reached. The present study aims at bridging the gap between these two extreme configurations. On the basis of direct numerical simulations, we explore the intermediate states of the flow-structure system. We identify two dominant components of the flow: a high-frequency component that relates to the stationary body wake and a low-frequency component synchronized with body motion. We show that the scenario of flow reconfiguration is driven by the opposite trends of these two component contributions.

Analysis of fluid dynamics to the riser of a FCC cold pilot plant aided with response surface methodology; Analise da fluidodinamica em um riser de FCC de uma unidade piloto a frio com auxilio da metodologia de superficie de resposta

Energy Technology Data Exchange (ETDEWEB)

Santos, Kamylla A.L. dos; Luna-Finkler, Christine L.; Lima Filho, Hilario J.B. de [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil); Benachour, Mohand; Dantas, Carlos Costa; Santos, Valdemir A. dos [Universidade Catolica de Pernambuco (UNICAP), Recife, PE (Brazil)

2012-07-01

It was planned and executed the implementation of a Central Composite Rotatable Design (CCRD) to the riser of a FCC (Fluid Catalytic Cracking) cold pilot plant, to identify the basic fluid dynamic characteristics of this type of reactor. The Fluid Catalytic Cracking is the major process in oil refineries in the world. It is realized in a vertical cylindrical reactor called riser, with a short contact time between the cracking catalyst and vacuum gas oil vapors. The constant evolution of the FCC process has required the analysis of fluid dynamics using computational fluid dynamics (CFD) software. However, analysis of images produced by the application of CFD to study of risers requires preliminary concepts of the relationship between response variables and independent variables. With the CCRD implementation was performed a total of 12 experiments, being 4 full factorial, 4 axial points and 4 central points. The dependent variables were the velocities of the components (cracking catalyst and compressed air) and the pressure drop in the riser. There was a great contribution of solids flow rate for the solid phase velocity and for the pressure drop. The effects of interaction between the flow rate phases are considerably senses in pressure drop through the riser, however, for the velocities of both phases this interaction becomes negligible. (author)

Spectral fatigue analysis of a tensioned riser compliant tower

NARCIS (Netherlands)

Karadeniz, H.; Vrouwenvelder, A.C.W.M.; Shi, C.

1998-01-01

In this paper, the conceptual Tensioned Riser Compliant Tower (TRCT) structure of the Shell Oil, which is developed for a region of approximately 600 meter water depth of the West of Shetlands in the North Sea, is analyzed by using the SAPOS program of the Delft University of Technology. The fatigue

Mathematics of flexible risers including pressure and internal flow affects

Energy Technology Data Exchange (ETDEWEB)

Seyed, F.B. (John Brown Engineers and Constructors Ltd., London (GB)); Patel, M.H. (University Coll., London (GB). Dept. of Mechanical Engineering)

1992-01-01

Derivations are presented for calculation of pressure and internal flow induced forces on flexible risers and other curved pipes using a mathematically rigorous approach. Approximate and exact methods are presented for calculation of pressure forces on straight and curved pipes in two dimensions. The mathematical identity of these equations with those for effective tension is illustrated. The force arising from the flow of an internal fluid of constant density is then calculated and combined with those for pressure forces in derivation of the catenary equations including pressure and internal flow terms. It is shown that internal flow contributes a new term to the expression for effective tension. These governing equations are then reduced for the specific cases of simple catenary, steep-S, lazy-S, steep-wave and lazy-wave risers. In each case, the solution method has been presented and the governing equilibrium and geometric compatability conditions cited. (author).

Refining fault slip rates using multiple displaced terrace risers-An example from the Honey Lake fault, NE California, USA

Science.gov (United States)

Gold, Ryan D.; Briggs, Richard W.; Crone, Anthony J.; DuRoss, Christopher B.

2017-11-01

Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4 difference observed globally) produce large uncertainties in the slip-rate estimate. In this investigation, we explore how the full range of displacements and bounding ages from multiple faulted terrace risers can be combined to yield a more accurate fault slip rate. We use 0.25-m cell size digital terrain models derived from airborne lidar data to analyze three sites where terrace risers are offset right-laterally by the Honey Lake fault in NE California, USA. We use ages for locally extensive subhorizontal surfaces to bracket the time of riser formation: an upper surface is the bed of abandoned Lake Lahontan having an age of 15.8 ± 0.6 ka and a lower surface is a fluvial terrace abandoned at 4.7 ± 0.1 ka. We estimate lateral offsets of the risers ranging between 6.6 and 28.3 m (median values), a greater than fourfold difference in values. The amount of offset corresponds to the riser's position relative to modern stream meanders: the smallest offset is in a meander cutbank position, whereas the larger offsets are in straight channel or meander point-bar positions. Taken in isolation, the individual terrace-riser offsets yield slip rates ranging from 0.3 to 7.1 mm/a. However, when the offset values are collectively assessed in a probabilistic framework, we find that a uniform (linear) slip rate of 1.6 mm/a (1.4-1.9 mm/a at 95% confidence) can satisfy the data, within their respective uncertainties. This investigation demonstrates that integrating observations of multiple offset elements (crest, midpoint, and base) from numerous faulted and dated terrace risers at closely spaced

A case study in flow assurance of a pipeline-riser system using OLGA

Energy Technology Data Exchange (ETDEWEB)

Nemoto, Rafael Horschutz; Balino, Jorge Luis [Nucleo de Dinamica e Fluidos. Dept. de Engenharia Mecanica. Universidade de Sao Paulo (EP/USP), SP (Brazil)], e-mails: rafael.nemoto@usp.br, jlbalino@usp.br; Tanaka, Rafael Loureiro; Godinho, Carlos Alberto [Prysmian Cables and Systems, Cariacica, ES (Brazil)], e-mails: rafael.tanaka@prysmian.com, carlos.godinho@prysmian.com

2010-07-01

In this paper, a case study in flow assurance is performed considering an offshore operating system, using the software OLGA. As operating system we consider a pipeline-riser geometry with typical dimensions of offshore oil production systems, and a three-phase flow of oil, gas and water. The model developed in OLGA considers the composition and dimensions of the tubes, heat transfer parameters, process equipment and fluid sources. The fluids properties are calculated using the software PVTsim. Simulations are ran in order to determine the pipeline inner diameter and insulation required to satisfy pressure and temperature requirements. It is also possible to simulate the transient behavior of the system, which allows to evaluate if production instabilities are present. In case instabilities exist, two mitigation alternatives are evaluated: closure of a choke valve before the separator and gas lift. Considering a possible production shutdown, the tubes insulation is calculated in order to avoid hydrate formation. (author)

Numerical investigation on effect of riser diameter and inclination on system parameters in a two-phase closed loop thermosyphon solar water heater

International Nuclear Information System (INIS)

Aung, Nay Zar; Li, Songjing

2013-01-01

Highlights: • Optimum inclination for maximum heat flux changes with latitude of location. • Optimum inclination for maximum heat flux also changes local solar time. • Maximum flow rate increases with increasing of riser tube size. • Maximum mass flow rate is obtained at different inclinations for different risers. • Length of two-phase region depends on inclination angles but not riser tube size. - Abstract: In this work, the effect of riser diameter and its inclination angle on system parameters in a two-phase closed loop thermosyphon solar water heater has been numerically investigated. Here, receivable heat flux by the collector, circulating mass flow rate, driving pressure, total pressure drop, heat transfer coefficient in risers and collector efficiency are defined as system parameters. For this aim, a model of two-phase thermosyphon solar water heater that is acceptable for various inclinations is presented and variations of riser diameter and inclination are considered. The riser tube size is varied from 1.25 cm to 2.5 cm with inclination range 2–75°. The system absolute pressure is set as 3567 Pa and water is chosen as working fluid. The results show that higher inclination angle is required for higher latitude location to obtain maximum solar heat flux. At local solar noon of 21.996 north latitude, the optimum inclination angle increases in the range of 24–44° with increasing of riser diameter giving maximum circulating mass flow rate from 0.02288 kg/s to 0.03876 kg/s. The longer two-phase heat transfer characteristics can be obtained at smaller inclination angles and mass flow rate for all riser tube sizes. Therefore, it is observed that the optimum inclination angles and diameters for solar heat flux, circulating mass flow rate and heat transfer coefficient in two-phase thermosyphon systemdo not coincide. From this work, better understanding and useful information are provided for constructing two-phase thermosyphon solar heaters

Flexible Riser Monitoring Using Hybrid Magnetic/Optical Strain Gage Techniques through RLS Adaptive Filtering

Directory of Open Access Journals (Sweden)

Daniel Pipa

2010-01-01

Full Text Available Flexible riser is a class of flexible pipes which is used to connect subsea pipelines to floating offshore installations, such as FPSOs (floating production/storage/off-loading unit and SS (semisubmersible platforms, in oil and gas production. Flexible risers are multilayered pipes typically comprising an inner flexible metal carcass surrounded by polymer layers and spiral wound steel ligaments, also referred to as armor wires. Since these armor wires are made of steel, their magnetic properties are sensitive to the stress they are subjected to. By measuring their magnetic properties in a nonintrusive manner, it is possible to compare the stress in the armor wires, thus allowing the identification of damaged ones. However, one encounters several sources of noise when measuring electromagnetic properties contactlessly, such as movement between specimen and probe, and magnetic noise. This paper describes the development of a new technique for automatic monitoring of armor layers of flexible risers. The proposed approach aims to minimize these current uncertainties by combining electromagnetic measurements with optical strain gage data through a recursive least squares (RLSs adaptive filter.

Mulheres idosas: desvelando suas vivências e necessidades de cuidado

Directory of Open Access Journals (Sweden)

Miriam Aparecida Barbosa Merighi

2013-04-01

Full Text Available Estudo qualitativo com abordagem da fenomenologia social que objetivou a compreensão da vivência da mulher idosa, suas necessidades de cuidado e expectativas nesse período da vida. Participaram nove mulheres, cujos depoimentos foram obtidos de fevereiro a maio de 2011, por meio de entrevista semiestruturada. A mulher idosa refere limitações de ordem física, mental e social, e valoriza a preservação de sua autonomia nas atividades diárias e no cuidado consigo mesma. Refere a família como suporte fundamental e tem expectativas e necessidades de se manter saudável, da busca pelo lazer e de ter melhor acesso aos serviços de saúde para receber informações e atendimento qualificado. Nessa fase, a ausência de perspectivas relaciona-se à perda de pessoas significativas e da saúde. Este estudo revelou facetas da vivência da mulher idosa, suscitando novas investigações e a adequação do ensino, prática e gestão às reais necessidades dessa mulher.

The impact of a grain of sand: increasing production speed in flexible risers generates significant savings in gas production

NARCIS (Netherlands)

Bokhorst, E. van; Blokland, H.

2012-01-01

Deep-sea oil and gas production normally involves the use of flexible risers that comprise a metal carcass with a large number of enveloping layers that safeguard the integrity of the pipe system. The flexible risers are hung from a floating platform and may be supported by several floating buoys to

A state space approach for the eigenvalue problem of marine risers

KAUST Repository

Alfosail, Feras

2017-10-05

A numerical state-space approach is proposed to examine the natural frequencies and critical buckling limits of marine risers. A large axial tension in the riser model causes numerical limitations. These limitations are overcome by using the modified Gram–Schmidt orthonormalization process as an intermediate step during the numerical integration process with the fourth-order Runge–Kutta scheme. The obtained results are validated against those obtained with other numerical methods, such as the finite-element, Galerkin, and power-series methods, and are found to be in good agreement. The state-space approach is shown to be computationally more efficient than the other methods. Also, we investigate the effect of a high applied tension, a high apparent weight, and higher-order modes on the accuracy of the numerical scheme. We demonstrate that, by applying the orthonormalization process, the stability and convergence of the approach are significantly improved.

Measurement of density distribution of a cracking catalyst in experimental riser with a sampling procedure for gamma ray tomography

International Nuclear Information System (INIS)

Dantas, C.C.; Melo, S.B.; Oliveira, E.F.; Simoes, F.P.M.; Santos, M.G. dos; Santos, V.A. dos

2008-01-01

By scanning a riser the number of the gamma ray trajectories and the beam width involve temporal, spatial and density resolutions as they are closely correlated parameters. Therefore, evaluation of parameters and their interaction quantification, certainly, are required in the imaging process. Measuring the density distribution of the catalyst from the FCC - fluid cracking catalytic process in an experimental riser in single beam tomographic system, density resolution is evaluated and correlated with spatial resolution. The beam width Δs inside riser is measured and a criterion for determining spatial resolution is proposed. Experiments are carried out to demonstrate resolution effects of three Δs values: 3.30 x 10 -3 , 6.20 x 10 -3 and 12.00 x 10 -3 m. The gamma beam profile is modeled and a sampling rate according to Nyquist criterion is analyzed. The 4.3%, 8.1% and 15.6% ratios of Δs/R to internal riser radius are correlated to counting time in the sampling procedure. Results are discussed by comparison with values from literature

Steel catenary riser design based on coupled analysis methodology; Projeto de um riser rigido em catenaria baseado em metodologia de analise acoplada

Energy Technology Data Exchange (ETDEWEB)

Bahiense, Rodrigo A.; Rodrigues, Marcos V. [Det Norske Veritas (DNV), Rio de Janeiro, RJ (Brazil)

2008-07-01

Due to adoption of oil and gas production systems to deep and ultra-deep water, achieving frontiers that were not conceivable before, research in computational methods has contributed to implementation of sophisticated and efficient numerical tools in order to perform simulations considering those operational conditions. Thus, this work presents a steel catenary riser (SCR) design which is connected to a semi-submersible platform where the applied motions to SCR are obtained from analyses based on de-coupled and coupled methodologies. With increase of the line number of the system and water depth, the effects due to coupling of the lines on the platform motions are significant. It can be observed from performed evaluations for a floating production system, comparing the obtained results for SCR under extreme and fatigue conditions when it was submitted to the platform motions considering both methodologies mentioned. So, from the results obtained it can be concluded that for production system evaluated the adoption of decoupled methodology presents more conservative results. Thus the adoption of the coupled model associated to design practice of production lines presents as an alternative more realist and accurate to provide the optimization in the design of these structures. (author)

Tools for Inspecting and Sampling Waste in Underground Radioactive Storage Tanks with Small Access Riser Openings

International Nuclear Information System (INIS)

Nance, T.A.

1998-01-01

Underground storage tanks with 2 inches to 3 inches diameter access ports at the Department of Energy's Savannah River Site have been used to store radioactive solvents and sludge. In order to close these tanks, the contents of the tanks need to first be quantified in terms of volume and chemical and radioactive characteristics. To provide information on the volume of waste contained within the tanks, a small remote inspection system was needed. This inspection system was designed to provide lighting and provide pan and tilt capabilities in an inexpensive package with zoom abilities and color video. This system also needed to be utilized inside of a plastic tent built over the access port to contain any contamination exiting from the port. This system had to be build to travel into the small port opening, through the riser pipe, into the tank evacuated space, and out of the riser pipe and access port with no possibility of being caught and blocking the access riser. Long thin plates were found in many access riser pipes that blocked the inspection system from penetrating into the tank interiors. Retrieval tools to clear the plates from the tanks using developed sampling devices while providing safe containment for the samples. This paper will discuss the inspection systems, tools for clearing access pipes, and solvent sampling tools developed to evaluate the tank contents of the underground solvent storage tanks

Vivências em espaços educativos: constituição de identidades homossexuais em homens adultos

OpenAIRE

Cechin, Andréa Forgiarini

2006-01-01

Esta pesquisa problematiza a relação entre a constituição das identidades homossexuais de homens adultos e suas vivências em espaços educativos formais, não formais e informais. Como ponto de partida para desenvolver o estudo, foram formuladas questões que focalizam percepções e sentimentos desses homens adultos em relação a si próprios e aos outros, tendo em vista suas vivências nesses espaços educativos e, especialmente, suas experiências de discriminação e resistência. Apoia-se teoricament...

A procedure to identify and to assess risk parameters in a SCR (Steel Catenary Riser) due to the fatigue failure

Energy Technology Data Exchange (ETDEWEB)

Stefane, Wania [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Faculdade de Engenharia Mecanica; Morooka, Celso K. [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Dept. de Engenharia de Petroleo. Centro de Estudos de Petroleo; Pezzi Filho, Mario [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). E and P. ENGP/IPMI/ES; Matt, Cyntia G.C.; Franciss, Ricardo [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

2009-12-19

The discovery of offshore fields in ultra deep water and the presence of reservoirs located in great depths below the seabed requires innovative solutions for offshore oil production systems. Many riser configurations have emerged as economically viable technological solutions for these scenarios. Therefore the study and the development of methodologies applied to riser design and procedures to calculate and to dimension production risers, taken into account the effects of mete ocean conditions, such as waves, current and platform motion in the fatigue failure is fundamental. The random nature of these conditions as well as the mechanical characteristics of the riser components are critical to a probabilistic treatment to ensure the greatest reliability for risers and minimum risks associated to different aspects of the operation like the safety of the installation, economical concerns and the environment. The current work presents a procedure of the identification and the assessment of main parameters of risk when considering fatigue failure. Static and dynamic behavior of Steel Catenary Riser (SCR) under the effects of mete ocean conditions and uncertainties related to total cumulative damage (Miner-Palmgren's rule) are taken into account. The methodology adopted is probabilistic and the approach is analytical. The procedure is based on the First Order Reliability Method (FORM) which usually presents low computational effort and acceptable accuracy. The procedure suggested is applied for two practical cases, one using data available from the literature and the second with data collected from an actual Brazilian offshore field operation. For both cases, results of the probability of failure due to fatigue were obtained for different locations along the SCR length connected to a semi-submersible platform. From these results, the sensitivity of the probability of failure due to fatigue for a SCR could be verified, and the most effective parameter could also be

Representação Social das Vivências de Estudantes no Curso de Medicina

Directory of Open Access Journals (Sweden)

Abrão Georges Restom

Full Text Available RESUMO A medicina atua com a prevenção e a cura das doenças humanas num sentido amplo. Uma formação com enfoque em problemas permite ao estudante um poder de análise dos componentes das situações de saúde. O Programa de Integração em Saúde da Comunidade (Pisco prevê levar estudantes e professores para a vivência da prática voltada à integralidade das ações, valorizando a prevenção e a promoção à saúde. O objetivo deste estudo foi analisar as vivências dos estudantes de Medicina no processo de avaliação das atividades do Pisco do primeiro ao quarto ano do curso e a sua relação com o projeto pedagógico do curso. Foi realizado um estudo descritivo quali-quantitativo. Foram produzidos registros escritos pelos estudantes ao final de cada encontro, de março de 2008 a dezembro de 2011, posteriormente analisados por meio do Discurso do Sujeito e pelo software QualiQuantiSoft®. Os resultados mostram diminuição do número de registros a partir da quinta etapa, pois a partir dela os alunos iniciam vivências em ambientes diferentes de prática médica e, assim, passam a desvalorizar as atividades no Programa de Saúde da Família.

Mulheres com gravidez de maior risco: vivências e percepções de necessidades e cuidado

Directory of Open Access Journals (Sweden)

Daniela do Carmo Oliveira

2015-03-01

Full Text Available Objetivo: Compreender vivências e percepções de mulheres com gestação de maior risco, relativas aos problemas/necessidades de saúde e práticas de cuidado. Métodos: Estudo descritivo-qualitativo, realizado em Cuiabá, Mato Grosso, com 12 mulheres em acompanhamento pré-natal em um serviço público especializado, por meio de entrevista semiestruturada e análise de conteúdo temática. Resultados: As participantes expressam a vivência de importantes eventos não médicos, que influem em sua saúde, como desinformação, medos, preocupações, desorganização da vida cotidiana e familiar, carências financeiras, e outras. Contudo, para o pré-natal, avalizam cuidados orientados pela perspectiva de risco, de controle dos problemas médicos. Reportam-se à necessidade de cuidados amplos, mas, para isso, buscam suporte na família e rede social comunitária de apoio. Conclusão: A compreensão das vivências e dos pontos de vista das mulheres grávidas é imprescindível à construção de ações pré-natais que respondam a necessidades de cuidados abrangentes.

A three-dimensional simulation of gas/particle flow and ozone decomposition in the riser of a circulating fluidized bed

DEFF Research Database (Denmark)

Hansen, Kim Granly; Solberg, Tron; Hjertager, Bjørn Helge

2004-01-01

The isothermal decomposition of ozone has been implemented in the CFD code FLOTRACS-MP-3D. The code is a 3D multiphase computational fluid dynamics code with an Eulerian description of both gas and particle phase. The turbulent motion of the particulate phase is modeled using the kinetic theory...... for granular flow, and the gas phase turbulence is modeled using a Sub-Grid-Scale model, cf. Ibsen et al. (2001). The decomposition reaction is studied in a 3D representation of a 0.254 m i.d. riser, which has been studied experimentally by Ouyang et al. (1993). The authors obtained profiles of ozone...

An analytic solution of the static problem of inclined risers conveying fluid

KAUST Repository

Alfosail, Feras

2016-05-28

We use the method of matched asymptotic expansion to develop an analytic solution to the static problem of clamped–clamped inclined risers conveying fluid. The inclined riser is modeled as an Euler–Bernoulli beam taking into account its self-weight, mid-plane stretching, an applied axial tension, and the internal fluid velocity. The solution consists of three parts: an outer solution valid away from the two boundaries and two inner solutions valid near the two ends. The three solutions are then matched and combined into a so-called composite expansion. A Newton–Raphson method is used to determine the value of the mid-plane stretching corresponding to each applied tension and internal velocity. The analytic solution is in good agreement with those obtained with other solution methods for large values of applied tensions. Therefore, it can be used to replace other mathematical solution methods that suffer numerical limitations and high computational cost. © 2016 Springer Science+Business Media Dordrecht

CFD Study of Industrial FCC Risers: The Effect of Outlet Configurations on Hydrodynamics and Reactions

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Gabriela C. Lopes

2012-01-01

Full Text Available Fluid catalytic cracking (FCC riser reactors have complex hydrodynamics, which depend not only on operating conditions, feedstock quality, and catalyst particles characteristics, but also on the geometric configurations of the reactor. This paper presents a numerical study of the influence of different riser outlet designs on the dynamic of the flow and reactor efficiency. A three-dimensional, three-phase flow model and a four-lump kinetic scheme were used to predict the performance of the reactor. The phenomenon of vaporization of the liquid oil droplets was also analyzed. Results showed that small changes in the outlet configuration had a significant effect on the flow patterns and consequently, on the reaction yields.

Vortex-Induced Vibration Tests of a Marine Growth Wrapped Cylinder at Subcritical Reynolds Number

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Kurian V. J.

2017-01-01

Full Text Available Vortex Induced Vibrations (VIV may cause great damage to deep water risers. Estimation of accurate hydrodynamic coefficients and response amplitudes for fouled tubular cylinders subjected to VIVs is a complex task. This paper presents the results of an extensive experimental investigation on in-line and cross-flow forces acting on cylinders wrapped with marine growth, subjected to current at Subcritical Reynolds Number. The drag and lift force coefficients have been determined through the use of the Fast Fourier Analysis methods. The different tests were conducted in the offshore engineering laboratory at Universiti Teknologi PETRONAS (UTP, Malaysia. In this study, a cylinder with outer diameter Do = 27 mm, fixed at top as cantilever beam was used. The in-line and cross-flow forces were measured using VIV Force Totaller (VIVFT. VIVFT is a two degree of freedom (2DOF forces sensor developed by UTP to measure the VIV forces. The tests were conducted for current velocity varied between 0.118 to 0.59 m/s. The test results suggest that the cylinder wrapped with marine growth has shown an overall increase in drag and inertia coefficients as well as on response amplitudes.

Vivências de familiares de crianças internadas em um Serviço de Pronto-Socorro

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Ana Maria Ribeiro dos Santos

2011-04-01

Full Text Available A infância apresenta-se como uma fase que exige bastante atenção da família e do serviço de saúde, uma vez que seus integrantes, além de dependerem de familiares, são vulneráveis ao ambiente. Objetivou-se descrever as vivências de familiares de crianças internadas em um serviço de pronto-socorro, discutir como essas vivências influenciam no cotidiano da família e relatar os aspectos que interferem no cuidado de enfermagem. Estudo descritivo, de abordagem qualitativa, desenvolvido em um hospital de urgência da rede privada. Utilizou a técnica de entrevista com dez familiares para produzir os dados. Estes foram submetidos à análise temática, elaborando-se três categorias: vivências do familiar, alterações no cotidiano da família, a fé e a aproximação familiar atuando como agentes facilitadores. Concluiu-se que o ser acompanhante passa por adaptações, ao vivenciar a hospitalização, existindo alterações na rotina familiar. Porém, devido aos conflitos vivenciados pelo familiar, a enfermagem deve compreendê-lo como sujeito do cuidado ampliado.

The use of titanium alloys for dynamic risers: a literature review

Energy Technology Data Exchange (ETDEWEB)

Torster, F.; Kocak, M.; Santos, J.F. dos [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung; Hutt, G. [Stolt Comex Seaway Ltd., Aberdeen, (Scotland)

1997-12-31

The main topic of this short literature review is to describe the material related aspects concerning the production and purpose of flexible titanium risers for offshore oil and gas production. Metallurgy and alloying of titanium are briefly introduced. The review concentrates on the materials properties that are relevant for the intended use in marine environment. The focus is put on {alpha}+{beta} Ti-alloys, because earlier investigations have shown that this alloy family is the most suitable one for this purpose. Further topics which are taken into account are welding processes for titanium, weld properties and aspects of the associated weld defects as well. This literature review has been carried out at GKSS-Forschungszentrum Geesthacht GmbH within the framework of the project `Titanium Risers for Deepwater Developments (contract nr. OG/175/95), supported by the THERMIE-JOULE Programme of the European Commission. The project consortium is formed by Stolt Comex Seaway Ltd. (UK), Seaflex AS (Norway) and GKSS (Germany). (orig.) [Deutsch] Die vorliegende kurze Literaturrecherche befasst sich vorrangig mit den materialbezogenen Aspekten der Produktion und des Einsatzes von flexiblen `Risern` aus Titanlegierungen fuer die Oel- und Gasfoerderung auf See. Die Metallurgie und das Legieren von Titan werden kurz vorgestellt. Die Recherche konzentriert sich im weiteren auf die Materialeigenschaften, die fuer den vorgesehenen Einsatz in mariner Umgebung von besonderer Bedeutung sind. In erster Linie wird dabei auf {alpha}+{beta}-Titanlegierungen eingegangen, da vorausgegangene Untersuchungen gezeigt haben, dass diese Legierungsfamilie die guenstigsten Eigenschaften fuer das vorgesehene Einsatzgebiet aufweist. Im weiteren werden die Schweissprozesse, die bei Titanlegierungen eingesetzt werden, vorgestellt und die Eigenschaften und moeglichen Schweissfehler der hergestellten Schweissverbindungen gegenuebergestellt. Diese Literaturrecherche wurde im GKSS-Forschungszentrum im

Necessary Tension in Marine Risers Tension des colonnes montantes en mer

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Lubinski A.

2006-11-01

Full Text Available The tension governing transverse static and dynamic deflections in a riser is not the actual tension but the so-called « effective tension » The concept of effective tension and effective compression is thoroughly explained, and means for calculating effective forces are given. Numerical examples are worked out for risers whose length is between 152 m (520 ft and 920 m (3020 ft. The reciprocal of maximum bending moment of the vicinity of the hall joint is plotted versus the effective tension of the ball joint. Bending moments used were obtained through use of static and dynamic computer programs applied ta a variety of conditions of wave loading, use or non-use of buoyant moterial sleeves, etc. The most important parameters affecting riser performance are the effective La tension régissant les déflections transversales statiques et dynamiques d'une colonne montante n'est pas la tension réelle mais ce qu'on appelle « la tension effective ». Le concept de tension ou de compression effective est expliqué en détail et la façon de calculer les forces effectives est indiquée dans cet article. Des exemples numériques sont développés pour des colonnes montantes de longueur comprise entre 152 m (520 ft et 920 m (3 020 ft. On a tracé la courbe de l'inverse du moment fléchissant en fonction de la tension effective à l'articulation. Les moments fléchissants utilisés ont été calculés par ordinateur en utilisant des programmes dynamiques et statiques pour des conditions variées d'action des vagues, la colonne montante étant ou non munie de manchettes de flottabilité, etc. Les deux paramètres les plus importants qui affectent le bon comportement d'une colonne montante sont la tension effective et la charge latérale.

Anchoring FRP Composite Armor in Flexible Offshore Riser Systems

DEFF Research Database (Denmark)

Costache, Andrei

things, they serve for the transportation of hydrocarbons from the subsea facilities to the production and drilling equipment at the sea surface. Flexible risers are the prime choice for connecting floating production, storage and offloading facilities, because they are specially designed for dynamic...... counterpart. A new double grip design with flat faces is proposed, in which the loads are transferred through friction. The behavior of such grip is studied by means of experimental testing and finite element modeling. Several iterations of the grip system were evaluated over the course of the project...

Studi Pengaruh Gerak Semi-submersible Drilling Rig dengan Variasi Pre-tension Mooring Line terhadap Keamanan Drilling Riser

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Arda Arda

2012-09-01

Full Text Available Analisis terhadap sistem tambat pada anjungan pengeboran semi-submersible drilling rig perlu dilakukan sebelum dilakukannya operasi di lapangan untuk mengetahui perencanaan sistem tambat yang tepat dan aman. Dalam penelitian ini dilakukan analisa perilaku gerak semi-submersible dengan variasi pre-tension mooring line untuk mengetahui berapa besar pre-tension minimal yang harus digunakan agar operasi pengeboran di lingkungan laut Natuna dapat berjalan dengan aman. Variasi pre-tension yang digunakan adalah sebesar 400kN-2000kN dengan penambahan sebesar 400kN. Karakteristik gerakan semi-submersible diprediksi dengan menghitung RAO free floating dengan pemodelan numerik dalam domain frekuensi. Kemudian dilakukan analisa simulasi sistem lengkap (platform, mooring dan drilling riser dengan pemodelan numerik dalam domain waktu. Hasil yang didapat yakni nilai maksimum tegangan mooring line memenuhi batas kriteria API-RP2SK untuk semua variasi pre-tension dengan safety factor terkecil 2.44. Sudut flex joint drilling riser yang terjadi melewati batas kriteria API-RP16Q pada pre-tension 400kN-800kN yang mencapai 6.20 untuk sudut maksimum dan 4.80 untuk sudut rata-rata. Tegangan von Mises yang terjadi pada drilling riser melebihi kriteria API-RP16Q pada pre-tension 400kN-1200kN karena nilainya mencapai 369 MPa (0.82 yield stress.

Vivências culturais paulistas da Ilustração Luso-brasileira

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Marisa Saenz Leme

2012-06-01

Full Text Available O objetivo do presente trabalho é o de recuperar as vivências que, entre a religiosidade tradicional e o laicismo, os paulistas tiveram da ilustração luso-brasileira, nos seus aspectos de cultura erudita. Entre as manifestações musicais, as realizações arquitetônicas e de artes plásticas, e as produções literárias e historiográficas, procura-se avaliar o significado do iluminismo em uma área da Colônia Brasil ainda pouco estudada nessa dimensão.

Adolescentes em tratamento psiquiátrico: um estudo fenomenológico das vivências em seus relacionamentos sócio-afetivos-sexuais

OpenAIRE

Fernanda Tomé Marleta Iezzi

2013-01-01

RESUMO Marleta-Iezzi, F. T. (2013) Adolescentes em tratamento psiquiátrico: um estudo fenomenológico das vivências em seus relacionamentos sócio-afetivo-sexuais. Dissertação de Mestrado Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto da Universidade de São Paulo, Ribeirão Preto. Na presente dissertação buscamos situar e (re)conhecer o fenômeno das vivências dos relacionamentos sócio-afetivo-sexuais de adolescentes submetidos a tratamento psiquiátrico, por compreender que a adol...

A vivência do cuidado familiar em casas transitórias de apoio

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Jaqueline Dias do Nascimento

2016-06-01

Full Text Available RESUMO Objetivo: apresentar modelo teórico representativo da vivência do cuidado em casas transitórias de apoio a familiares de crianças em pós-transplante de células-tronco hematopoiéticas. Método: Teoria Fundamentada nos Dados, realizada com 18 participantes de três grupos amostrais. Para análise, utilizou-se o software QSR Nvivo10. Resultados: elaboraram-se quatro categorias: residindo em casa transitória de apoio; vivenciando o cuidado à criança em pós-transplante de células-tronco hematopoiéticas; cuidando do cuidador familiar; e retornando a uma nova vida no lar, as quais se inter-relacionam conforme o código teórico da família interativa. Conclusão: esta pesquisa contribui para compreensão da vivência do cuidado em casas transitórias de apoio a familiares de crianças em pós-transplante de células-tronco hematopoiéticas e subsidia as ações de enfermagem e saúde prestadas a esta população; contribui ainda para a elaboração de orientação de alta hospitalar e cuidado direcionado a essa clientela.

Effect of flow on corrosion in catenary risers and its corrosion inhibitor performance

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Pedro Altoe; Magalhaes, Alvaro Augusto Oliveira; Silva, Jussara de Mello [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Kang, Cheolho; More, Parimal P. [Det Norske Veritas (DNV), Oslo (Norway)

2009-07-01

In oil and gas production, multiphase flow is often encountered and a range of different flow patterns can be experienced in pipelines. The flow regime transition and flow characteristics can be changed with the change of pipeline topography, which affects the corrosion and the performance of corrosion inhibitor in these multiphase pipelines. This paper outlines on the effect of inclination on the flow characteristics and their subsequent effect on corrosion rates. Also, this paper presents on the performance of three candidate corrosion inhibitors under severe slugging conditions at low water cut. For the simulation of offshore flow lines and risers, the experiments were carried out in a 44 m long, 10 cm diameter, three different pipeline inclinations of 0, 3 and 45 degrees. Light condensate oil with a viscosity of 2.5 cP at room temperature was used and water cut was 20%. The results indicated that the baseline corrosion rate in 45 degrees showed higher than other inclinations. Each corrosion inhibitor showed a different inhibitor performance. (author)

On the modelling and the analysis of two-phase flow instabilities in pipeline-riser systems; Modelisation et analyse des instabilites d'ecoulements diphasiques dans les conduites petrolieres du type pipeline-riser

Energy Technology Data Exchange (ETDEWEB)

Zakarian, E.

2000-03-10

Recent estimations predict that over half the remaining offshore oil and gas reserves are located in deep water and marginal fields. For such reserves, economic recovery methods are required. Then, multiphase flows are transported within pipelines and separated on treatment platforms built in shallow water or processed in onshore facilities. Unfortunately, hydrodynamic instabilities may occur whenever gas and liquid flow in a pipeline, generating serious operating problems. This dissertation presents a new way to model two-phase flows in pipelines such as pipeline-riser systems. Equations are algebraic and differential. Their smoothness depends on the closure laws of the problem such as slip or friction laws. Smooth forms of these closure laws are presented for the first time in this dissertation. Therefore, a mathematical analysis of our model fits into a classical frame: a linear analysis leads to an analytical expression of the boundary between stable and unstable flows. A nonlinear analysis provides for the first time, the bifurcation curves of gas-liquid flows in pipe-riser systems, locally round their stability boundary. (author)

Adaptação, rendimento, evasão e vivências acadêmicas no ensino superior: revisão da literatura

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Cristiane Maria Barra da Matta

Full Text Available Resumo O início da vida acadêmica é um período de grandes mudanças para o estudante, que muitas vezes é tratado de forma infantilizada no ensino médio e se depara com as responsabilidades e exigências da universidade. O presente trabalho teve como objetivo revisar artigos, publicados entre 2005 e 2015, referentes à adaptação universitária relacionada às vivências acadêmicas, rendimento e evasão, no curso de Engenharia. Para tanto, foram realizadas pesquisas nas seguintes bases de dados eletrônicos: Biblioteca Virtual de Saúde (BVS, Scielo Brasil e Portal de Periódicos Eletrônicos de Psicologia (PePSIC.Utilizaram-se os descritores: adaptação acadêmica, vivências acadêmicas, rendimento acadêmico, evasão e engenharia. Foram encontrados 55 artigos, porém somente 16 atenderam os critérios de inclusão. A maioria dos artigos empíricos relacionados (66,7% utiliza o instrumento Questionário de Vivências Acadêmicas (QVA ou Questionário de Vivências Acadêmicas - versão reduzida (QVA-r. Dois deles (13,3% utilizaram esse instrumento conjuntamente com o Inventário de Habilidades Sociais e outros três (20,0% com o Questionário de caracterização dos estudantes. Conclui-se que os relacionamentos interpessoais podem favorecer o rendimento acadêmico e adiar a evasão, assim como os serviços de apoio aos estudantes; e constatou-se a escassez do tema em questão nos cursos de engenharia.

Multiport riser and flange assemblies acceptance test report

International Nuclear Information System (INIS)

Precechtel, D.R.; Schroeder, B.K.

1994-01-01

This document presents the results of the acceptance test for the multiport riser (MPR) and multiport flange (MPF) assemblies. The accepted MPR and MPF assemblies will be used in support of the hydrogen mitigation project for double-shell waste tank 241-SY-101 and other related projects. The testing described in this document verifies that the mechanical and interface features are operating as designed and that the unit is ready for field service. The objectives of the acceptance testing were as follows: Basic equipment functions and mechanical interfaces were verified; Installation and removal of equipment were demonstrated to the degree possible; Operation of the decon spray system and all valving was confirmed; and the accumulated leak rate of the MPR and MPF assemblies was determined

The use of low-radius circular-cross-section helical strakes for the reduction of VIV of tapered cylinders at high Reynolds numbers

DEFF Research Database (Denmark)

Johansson, Jens; Christensen, Silas Sverre

2018-01-01

% for strakes of circular cross section. The present paper argues that this height can be reduced for structures where the critical wind velocity for vortex shedding is in the Supercritical Reynolds number regime. The investigations are aimed for suppressing VIV on offshore wind turbine towers during......^5, i.e. in the Supercritical Reynolds number regime. Results indicate that circular strakes with a diameter corresponding to 3% of the mean diameter of the structure can be used to efficiently reduce VIV at Supercritical Reynolds numbers. This suggests that e.g. robes may be used as temporary helical...

Study for a stress joint at the top of a SCR (Steel Catenary Risers); Estudo de 'stress joints' para o topo de um SCR (Steel Catenary Risers)

Energy Technology Data Exchange (ETDEWEB)

Siqueira, Elizabeth Frauches Netto; Andrade, Edmundo Queiroz de [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

2008-07-01

Steel Catenary Risers, SCRs, need a top connection that bears the force transmitted to the platform. Essentially, two types of connections exist on the market: flex joint and stress joint (SJ). PETROBRAS has a SCR with top connection of flex joint type installed on one of its platforms; however, the company has been studying SJ as an option out of SCR top connection. A stress joint is a monolithic structure and can be inspected during manufacture and service, without so many difficult. They are metal structures composed of a uniform bore inserted in a tapered wall that increases gradually to support the force coming from the riser. The objective of this paper is to present a SJ sensitivity study for a production SCR supposedly hardwired to a unit of production of the semi-submersible type. The data used is based on real SCR data. For this study, global and local analyses were conducted for some models of stress joints, varying some parameters such as material and dimensions, allowing for the verification of some of the critical points of this type of connection. The results obtained will be shown in graphs and tensions maps to illustrate comparatively the critical points of the models analyzed. (author)

An accurate and computationally efficient small-scale nonlinear FEA of flexible risers

OpenAIRE

Rahmati, MT; Bahai, H; Alfano, G

2016-01-01

This paper presents a highly efficient small-scale, detailed finite-element modelling method for flexible risers which can be effectively implemented in a fully-nested (FE2) multiscale analysis based on computational homogenisation. By exploiting cyclic symmetry and applying periodic boundary conditions, only a small fraction of a flexible pipe is used for a detailed nonlinear finite-element analysis at the small scale. In this model, using three-dimensional elements, all layer components are...

Simulation of gas and particle flow in a circulating fluidized bed; Kaasu- ja kiintoainevirtauksen simulointi kiertoleijukattilassa

Energy Technology Data Exchange (ETDEWEB)

Kallio, S. [Aabo Akademi, Turku (Finland). Inst. of Heat Engineering

1996-12-01

The aim of this work was to study the effects of different parameters on the flow behaviour in a CFB riser by means of empirical models based on measurement data and a computer code based on macroscopic equations for multiphase flow. The effects of primary air velocity and riser geometry have been observed in the results. Simulation of secondary air flow proved to be problematic with the software used. In the project, also analyses of measurement data from cold model experiments has been performed. Moreover, the possibilities to use commercial CFD codes for simulation of gas-solids flow were investigated. The code FLUENT seemed promising. (author)

Vivências de mães de crianças diabéticas

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Déa Silvia Moura da Cruz

Full Text Available Resumo Objetivo: Compreender a vivência de mães de crianças com diabetes mellitus tipo 1. Métodos: Pesquisa qualitativa, realizada com cinco mães de crianças diabéticas atendidas no ambulatório de um hospital público em outubro de 2014. Os dados foram analisados à luz da Teoria Humanística de Enfermagem. Resultados: Emergiram as seguintes temáticas: As mães diante do diagnóstico de diabetes mellitus tipo 1; O cuidado materno como relação de doação (a relação EU-TU; Dificuldades enfrentadas pelas mães ao cuidarem da criança diabética; Convivência conflituosa entre as crianças diabéticas e suas mães; As mães recebem o apoio da família e da equipe multiprofissional (a relação NÓS; As mães diante do medo da morte. Conclusão: Na vivência da relação EU-TU estabelecida entre a pesquisadora e as mães, é possível perceber que o cuidado que elas dispensam aos seus filhos é repleto de envolvimento, de amor, de sensibilidade e de responsabilização com o outro, apesar das dificuldades e dos conflitos vivenciados diuturnamente.

Hybrid Composite Tensile Armour Wires in Flexible Risers: A Multi-scale Model

OpenAIRE

Gautam, Mayank; Katnam, Kali-Babu; Potluri, Venkata; Jha, Vivekanand; Latto, J.; Dodds, NI

2017-01-01

Traditional carbon-steel armour wires pose limitations (e.g. long spans, weight reduction, corrosion and fatigue) for flexible risers to operate in demanding and deeper water environments. In this context, an alternative to carbon-steel tensile armour wires is proposed recently by the authors (Gautam et al. [1]), comprising of hexagonally packed polymer composite rods with uni-directional fibres and an over-braided (i.e. bi-axial braid with high performance fibres) sleeve. These hybrid compos...

Influence of cross-sectional ratio of down comer to riser on the efficiency of liquid circulation in loop air lift bubble column

Science.gov (United States)

Yamamoto, Tatsumi; Kawasaki, Hiroyuki; Mori, Hidetoshi

2017-11-01

Loop type bubble columns have good performance of liquid circulation and mass transfer by airlift effect, where the liquid circulation time is an important measurable characteristic parameter. This parameter is affected by the column construction, the aspect ratio of the column, the cross-sectional area ratio of down comer to riser (R), and the superficial gas velocity in the riser (UGR). In this work, the mean gas holdup and the liquid circulation time (TC) have been measured in four types of loop airlift type bubble column: concentric tube internal loop airlift type, rectangular internal loop airlift type, external loop airlift type, external loop airlift with separator. Air and tap water were used as gas and liquid phase, respectively. The results have demonstrated that the mean gas holdup in riser increases in proportion to UGR, and that it in downcomer changes according to the geometric parameters of each bubble column. TC has been found to conform to an empirical equation which depends on UGR and the length of draft tube or division plate in the region of 0.33 < R < 1.

Faulted terrace risers place new constraints on the late Quaternary slip rate for the central Altyn Tagh fault, northwest Tibet

Science.gov (United States)

Gold, R.D.; Cowgill, E.; Arrowsmith, J.R.; Chen, X.; Sharp, W.D.; Cooper, K.M.; Wang, X.-F.

2011-01-01

The active, left-lateral Altyn Tagh fault defines the northwestern margin of the Tibetan Plateau in western China. To clarify late Quaternary temporal and spatial variations in slip rate along the central portion of this fault system (85??-90??E), we have more than doubled the number of dated offset markers along the central Altyn Tagh fault. In particular, we determined offset-age relations for seven left-laterally faulted terrace risers at three sites (Kelutelage, Yukuang, and Keke Qiapu) spanning a 140-km-long fault reach by integrating surficial geologic mapping, topographic surveys (total station and tripod-light detection and ranging [T-LiDAR]), and geochronology (radiocarbon dating of organic samples, 230Th/U dating of pedogenic carbonate coatings on buried clasts, and terrestrial cosmogenic radionuclide exposure age dating applied to quartz-rich gravels). At Kelutelage, which is the westernmost site (37.72??N, 86.67??E), two faulted terrace risers are offset 58 ?? 3 m and 48 ?? 4 m, and formed at 6.2-6.1 ka and 5.9-3.7 ka, respectively. At the Yukuang site (38.00??N, 87.87??E), four faulted terrace risers are offset 92 ?? 12 m, 68 ?? 6 m, 55 ?? 13 m, and 59 ?? 9 m and formed at 24.2-9.5 ka, 6.4-5.0 ka, 5.1-3.9 ka, and 24.2-6.4 ka, respectively. At the easternmost site, Keke Qiapu (38.08??N, 88.12??E), a faulted terrace riser is offset 33 ?? 6 m and has an age of 17.1-2.2 ka. The displacement-age relationships derived from these markers can be satisfied by an approximately uniform slip rate of 8-12 mm/yr. However, additional analysis is required to test how much temporal variability in slip rate is permitted by this data set. ?? 2011 Geological Society of America.

Two-riser system improves drilling at Auger prospect

International Nuclear Information System (INIS)

Gonzalez, R.; Marsh, G.L.; Ritter, P.B.; Mendel, P.E.

1992-01-01

This paper reports on a two-rise system (TRS) for drilling deepwater development wells which eliminates some of the limitations of conventional subsea technology and allows flexibility in well programs. Shell Offshore Inc.'s deep exploratory wells in Garden Banks 426 and 471 have encountered drilling problems that were attributed to limitations in casing sizes imposed by conventional subsea drilling systems. These problems are not uncommon in exploratory deepwater, deep well drilling in the Gulf of Mexico. Reservoir depths of up to 19,500 ft true vertical depth (TVD) and 7-in. production casing requirements led to potentially troublesome and expensive well plans. Because of the constraints placed on the development drilling program by completion requirements and directional drilling, a two-riser system was designed and fabricated. Solving such significant drilling problems has reduced overall development costs

DENSE MULTIPHASE FLOW SIMULATION: CONTINUUM MODEL FOR POLY-DISPERSED SYSTEMS USING KINETIC THEORY

Energy Technology Data Exchange (ETDEWEB)

Moses Bogere

2011-08-31

The overall objective of the project was to verify the applicability of the FCMOM approach to the kinetic equations describing the particle flow dynamics. For monodispersed systems the fundamental equation governing the particle flow dynamics is the Boltzmann equation. During the project, the FCMOM was successfully applied to several homogeneous and in-homogeneous problems in different flow regimes, demonstrating that the FCMOM has the potential to be used to solve efficiently the Boltzmann equation. However, some relevant issues still need to be resolved, i.e. the homogeneous cooling problem (inelastic particles cases) and the transition between different regimes. In this report, the results obtained in homogeneous conditions are discussed first. Then a discussion of the validation results for in-homogeneous conditions is provided. And finally, a discussion will be provided about the transition between different regimes. Alongside the work on development of FCMOM approach studies were undertaken in order to provide insights into anisotropy or particles kinetics in riser hydrodynamics. This report includes results of studies of multiphase flow with unequal granular temperatures and analysis of momentum re-distribution in risers due to particle-particle and fluid-particle interactions. The study of multiphase flow with unequal granular temperatures entailed both simulation and experimental studies of two particles sizes in a riser and, a brief discussion of what was accomplished will be provided. And finally, a discussion of the analysis done on momentum re-distribution of gas-particles flow in risers will be provided. In particular a discussion of the remaining work needed in order to improve accuracy and predictability of riser hydrodynamics based on two-fluid models and how they can be used to model segregation in risers.

Recasamento: percepções e vivências dos filhos do primeiro casamento

OpenAIRE

Valentim de Sousa, Daniela Heitzmann Amaral; Dias, Cristina Maria de Souza Brito

2014-01-01

Esta pesquisa teve como objetivo compreender as percepções e as vivências de filhos diante das mudanças ocorridas em suas vidas, no âmbito da convivência familiar, devido ao recasamento de um ou de ambos os pais. É uma pesquisa qualitativa cujos participantes são quatro adultos jovens. Eles responderam a uma entrevista analisada de acordo com a Análise de Conteúdo Temática. Pode-se concluir que, apesar das dificuldades iniciais devido às alterações na estrutura física, na rotina e na dinâmica...

Violência: conceito e vivência entre acadêmicos da área da saúde

Directory of Open Access Journals (Sweden)

Rosiléia Rosa

Full Text Available Trata-se de uma investigação sobre conceitos e vivências sobre violência de acadêmicos do último ano dos cursos de graduação em Enfermagem, Medicina e Odontologia da Universidade Federal de Santa Catarina. Caracterizada como uma pesquisa descritiva exploratória com abordagem qualiquantitativa com 175 acadêmicos, a proposta foi compreender qual a definição de violência para os acadêmicos, quais suas vivências sobre o tema e qual a inserção que o tema violência teve durante a formação acadêmica. As definições sobre violência estiveram fortemente relacionadas a uma visão técnica e priorizaram os danos físicos sofridos pelas pessoas agredidas. Diante de uma situação de violência os acadêmicos reproduziram sentimentos de medo, impotência, raiva e indignação e não reagiram ao presenciar tais atos; evidenciaram que o profissional de saúde não identifica situações de violência quando presta assistência de forma superficial às vítimas; e que a formação acadêmica não discute o tema suficientemente.

ALARA plan for the Old Hydrofracture Facility tanks contents removal project at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Amendment 1 for Appendix B: Install flex-pipe on tank riser spools

International Nuclear Information System (INIS)

1998-01-01

This amendment to Appendix B contains the specific ALARA evaluations for installing flex-pipe on riser spools to accommodate ventilation duct connections to the north risers of each tank. The work will be a routine task that is part of the Equipment Installation and Mobilization phase of the project. The dose rates were estimated using the recent Radiological Surveillance Section radiological survey: SAAS-97-063S. Task B-6 has been added to the OHF Project ALARA review process to address a field decision to modify an approach to installing the tank ventilation system. The revised approach will incorporate 12-in. diameter, 36-in. long, stainless steel flex-pipe connected to each north riser spool to address the problem of pipe fitting multiple bends and turns expected with the 12-in. PVC duct. This improved approach will reduce the time necessary to install the duct system between the tanks and the ventilation skid. However, the task includes opening the 12-in. riser spool connections to replace the currently installed blind gaskets. Since a riser spool for each tank will be opened, there is a potential for significant personnel exposure and spread of contamination that will addressed through this ALARA review process

“... Essa coisa começou a pegar!” – vivências cotidianas de homens obesos

Directory of Open Access Journals (Sweden)

Carminda Maria Goersch Fontenele Lamboglia

2016-03-01

Full Text Available Objetivo: Conhecer as vivências cotidianas de homens com obesidade mórbida. Métodos: Pesquisa com abordagem qualitativa. Foram entrevistados nove homens com diagnóstico de obesidade mórbida que estavam em seguimento no pré-operatório para cirurgia bariátrica, com idade de 27 a 50 anos, casados, com renda familiar de dois a três salários mínimos, caso de obesidade na família e hipertensão como comorbidade. A investigação ocorreu no período de maio a setembro de 2012 em um hospital de referência no tratamento à obesidade e realização de cirurgia bariátrica em Fortaleza, Ceará, Brasil. Realizaram-se entrevistas semiestruturadas com análise, através da Análise de Conteúdo, do tipo análise temática. Eis as categorias de análise definidas: tornar-se obeso, vivências cotidianas do homem obeso e cirurgia bariátrica – um caminho possível para um cotidiano com saúde. Resultados: Os principais achados relacionaram-se a uma rotina diária fixa, com reduzido espaço para atividade física e de lazer. A obesidade, para 90% dos entrevistados, existe desde a infância e trouxe dificuldade na realização das ocupações no dia a dia. Esses homens optaram pela cirurgia por não perderem peso com dieta, exercício e medicamento, em razão da permanência de problemas de saúde, bem como dificuldades nas relações afetivas e no trabalho. Conclusão: Identificou-se a demanda de uma reorganização das vivências cotidianas dos homens para que haja uma efetiva ação da cirurgia bariátrica, a fim de que os usuários sejam protagonistas dessa modificação, inserindo atividades saudáveis e contínuas no seu cotidiano.

Transcatheter heart valve in valve implantation with Edwards SAPIEN bioprosthetic valve for different degenerated bioprosthetic valve positions (First Iranian ViV report with mid-term follow up

Directory of Open Access Journals (Sweden)

Ali Mohammad Haji Zeinali

2017-09-01

Conclusion: As the first Iranian all-comers case series with midterm follow up for ViV implantation, we had no mortality. Interestingly none of our patients had neurologic sequelae after the procedure. Midterm follow up for our patients was acceptable with good functional class and appropriate echocardiographic findings. Due to high surgical risk of the redo procedure after failing of a bioprosthetic valve especially in elderly patients with comorbidities, ViV implantation would be a good alternative to surgery for this high risk group.

Estudo do efeito de um "Riser Blowout" na perfuração de poços de petroleo em aguas profundas

OpenAIRE

Heitor Rodrigues de Paula Lima

1991-01-01

Resumo: Esta dissertação apresenta uma análise do comportamento da pressão dos fluidos que ocorre durante o especial acidente na perfuração de um poço submarino de petróleo conhecido como "Riser Blowout" ( * ). O modelo usado neste estudo baseia-se na solução do sistema de equações diferenciais parciais que governam o fluxo ascendente da mistura bifásica fluido de perfuração/ gás dentro do espaço anular entre a coluna de perfuração e o "marine riser". As perdas de carga devido a aceleração do...

Comportement mécanique des tuyaux. Influence de la traction, de la pression et du poids linéique. Application aux risers Mechanical Behavior of Pipes and Risers. Influence of Tension, Pressure and Weight

Directory of Open Access Journals (Sweden)

Sparks C.

2006-11-01

Full Text Available L'influence de la traction, de la pression et du poids linéique sur le comportement d'un tuyau (ou d'un riser a déjà été traitée dans de nombreux articles. Malgré cela, elle est fréquemment mal comprise, ce qui a parfois de; conséquences sérieuses. Par souci de clarté, l'approche de cet article est délibérément très élémentaire. Les problèmes principaux de la flexion, du flambage, de l'allongement et de la contrainte limite, qui sont souvent traités dans des articles différents, sont ici étudiés ensemble d'une façon homogène. On présente des interprétation: physiques, faciles à visualiser, des deux concepts de tension effective et de contrainte effective, dont l'utilisation est très répandue, ainsi que leur rapport avec des notions analogues dans d'autres domaines de l'art de l'ingénieur. La puissance de ces deux concepts est démontrée à la fin de l'article où ils sont utilisés pour résoudre huit problèmes divers. The influence of tension, pressure, and weight on different aspects of pipe and riser behavior has already been the subject of many articles (see references. In spite of this it has frequently been misunderstood, sometimes with serious consequences. The object of this payer is to explain the subject clearly and the approach is therefore deliberately very elementary. The principal problems of bending, buckling, yielding and strains, usually treated in separated papers, are here treated homogeneously. The widely used concepts of effective tension and effective stress are given interpretations, easy to visualise, which are related to analogous concepts in other engineering fields. Finally, eight diverse particular examples of the influence of tension, pressure and weight on pipe and riser behavior, are discussed.

Impact Of Particle Agglomeration On Accumulation Rates In The Glass Discharge Riser Of HLW Melter

International Nuclear Information System (INIS)

Kruger, A. A.; Rodriguez, C. A.; Matyas, J.; Owen, A. T.; Jansik, D. P.; Lang, J. B.

2012-01-01

The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with x-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, and on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ∼185+-155 μm, and produced >3 mm thick layer after 120 h at 850 deg C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers

75 FR 26091 - Safety Zone; Riser for DEEPWATER HORIZON at Mississippi Canyon 252 Outer Continental Shelf MODU...

Science.gov (United States)

2010-05-11

... the Gulf of Mexico AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is... personnel involved in oil pollution response efforts. Placing a safety zone around the riser will... the water's surface and subsurface. DATES: Effective Date: This rule is effective in the CFR on May 11...

Amamentação e sexualidade: uma interface na vivência do puerpério Breastfeeding and sexuality: an interface in the experience of puerperium

Directory of Open Access Journals (Sweden)

Liese Klimeck Brauner Pissolato Pissolato

2016-07-01

Full Text Available Objetivo: compreender a influência da amamentação na vivência da sexualidade, sob a ótica de um grupo de puérperas. Método: pesquisa qualitativa descritiva, realizada com mulheres que estavam vivenciando o puerpério. Os dados foram coletados por meio de entrevista individual semiestruturada e submetidos à análise de conteúdo temática da proposta operativa. Resultados: a vivência da sexualidade durante a amamentação foi marcada por desconfortos relacionados às mudanças no relacionamento sexual, alterações corporais, tempo restrito da mulher com o parceiro, além de alguns comportamentos negativos do companheiro. Em outros casos, a amamentação não trouxe mudanças significativas na vivência da sexualidade, contribuindo para o companheirismo e parceria entre o casal. Conclusões: é preciso ampliar o olhar sobre a temática da sexualidade durante a amamentação, percebendo-a como uma necessidade humana básica, que precisa ser discutida entre mulheres, casais e profissionais de saúde.

Influence of roadside infrastructure on driving behavior: driving simulator study

NARCIS (Netherlands)

Horst, A.R.A. van der; Ridder, S. de

2007-01-01

This paper describes the results of a driving simulator study that focused on the influence of roadside infrastructure on speed choice and lateral placement of car drivers. A review of the RISER detailed accident database revealed that lateral positioning and speed of the vehicle were two of the

Learning control for riser-slug elimination and production-rate optimization for an offshore oil and gas production process

DEFF Research Database (Denmark)

Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

2014-01-01

, (ii) maximizing the production rate at the riser of an offshore production platform, by manipulating a topside choke valve through a learning switching model-free PID controller. The results show good steady-state performance, though a long settling time due to the unknown reference for no slugging...

Some aspects of arctic offshore floating structures

Energy Technology Data Exchange (ETDEWEB)

Lubbad, Raed Khalil

2011-01-15

The present work highlights some aspects related to the analyses of Arctic offshore floating structures. This thesis consists of five papers, which can be divided into two main categories. One category deals with the dynamics of slender structures with an emphasis on the prediction and suppression of vortex induced vibrations (VIV), and the other category examines the process of interaction between sloping structures and sea ice with focus on developing a numerical model to simulate this process in real time. Slender structures, such as mooring lines and marine risers, are very important for the offshore petroleum industry, which is currently approaching deeper waters. Increasingly, attention has been focused on predicting the susceptibility of these structures to VIV. In this thesis, two asymptotic techniques namely, the local analysis and the WKB methods, were used to derive closed-form solutions for the natural frequencies and mode shapes of slender line-like structures. Both the top-tensioned nearly-vertical configuration and the catenary configuration were considered. The accuracy of the solutions derived was established through comparison with other analytic solution techniques and with results of numerical finite element solutions. The effects of the bending stiffness and the effects of approximating the tension variation as a linear function were discussed. Experimental data on the multi-modal in-line and cross-flow response behaviour of a towed catenary model were analysed to examine the usefulness of the solutions for predicting the response frequencies and envelopes due to VIV. Helical strakes are often used as a mitigating measure to suppress the VIV of slender structures. This thesis presented an innovative method to fit ropes helically to a riser in the installation phase. Such a procedure will help to overcome the handling problem associated with the use of conventional sharp-edged strakes. Experimental investigations were then performed to verify

HDPE (High Density Polyethylene) pipeline and riser design in Guanabara Bay: challenges and solutions

Energy Technology Data Exchange (ETDEWEB)

Bomfimsilva, Carlos; Jorge, Joao Paulo Carrijo; Schmid, Dominique; Gomes, Rodrigo Klim [INTECSEA, Sao Paulo, SP (Brazil); Lima, Alexander Piraja [GDK, Salvador, BA (Brazil)

2009-12-19

Worldwide shipments of plastic pipes are forecasted to increase 5.2% per year since 2008, being commonly used for water supply and sewage disposal. The HDPE (High Density Polyethylene) pipes have been applied recently to deliver potable water and fire fighting water for the main pier of the LNG system in Guanabara Bay, Rio de Janeiro. The system contains three sizes of pipe outside diameter, 110 mm and 160 mm for water supply, and 500 mm for the fire fighting system. The main design challenges of the pipeline system included providing on-bottom stability, a suitable installation procedure and a proper riser design. The on-bottom stability calculations, which are quite different from the conventional steel pipelines, were developed by designing concrete blocks to be assembled on the pipeline in a required spacing to assure long term stability, knowing that plastic pipes are buoyant even in flooded conditions. The installation procedure was developed considering the lay down methodology based on surface towing technique. The riser was designed to be installed together with additional steel support structure to allow the entire underwater system to have the same plastic pipe specification up to the surface. This paper presents the main challenges that were faced during the design of the HDPE pipelines for the LNG system in Guanabara Bay, addressing the solutions and recommendations adopted for the plastic underwater pipeline system.

Vivências de mães de crianças diabéticas

OpenAIRE

Cruz, Déa Silvia Moura da; Collet, Neusa; Andrade, Edineide Maria Costa de; Nóbrega, Vanessa Medeiros da; Nóbrega, Maria Miriam Lima da

2017-01-01

Resumo Objetivo: Compreender a vivência de mães de crianças com diabetes mellitus tipo 1. Métodos: Pesquisa qualitativa, realizada com cinco mães de crianças diabéticas atendidas no ambulatório de um hospital público em outubro de 2014. Os dados foram analisados à luz da Teoria Humanística de Enfermagem. Resultados: Emergiram as seguintes temáticas: As mães diante do diagnóstico de diabetes mellitus tipo 1; O cuidado materno como relação de doação (a relação EU-TU); Dificuldades enfrentada...

Aspectos éticos considerados na relação médico-paciente: vivências de anestesiologistas

Directory of Open Access Journals (Sweden)

Maria de Fátima Oliveira dos Santos

2013-10-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: Os princípios da ética orientam a forma de ser e agir do profissional, particularmente no estabelecimento da relação médico-paciente, e por isso, demandam constante reflexão. Nesse sentido, o propósito deste estudo é analisar vivências éticas de anestesiologistas em sua interação com o paciente sob seus cuidados. MÉTODO: Estudo exploratório, que envolveu 16 médicos anestesiologistas com exercício profissional em um hospital universitário de João Pessoa, Paraíba. Os dados foram coletados por meio de entrevista semiestruturada e analisados qualitativamente com o uso da técnica de análise de conteúdo. RESULTADOS: Os achados do estudo evidenciam que as vivências éticas dos participantes do estudo na relação médico-paciente foram classificadas em cinco categorias temáticas: respeito ao paciente, tratamento humanizado, tratamento igualitário, sigilo profissional e respeito à autonomia do paciente. CONCLUSÕES: Conclui-se que os entrevistados reconhecem a ética e os valores humanísticos que devem pautar a relação com seus pacientes.

Rituais de cuidado realizados pelas famílias na preparação para a vivência do parto domiciliar planejado

Directory of Open Access Journals (Sweden)

Iara Simoni Silveira Feyer

2013-12-01

Full Text Available Esta pesquisa etnográfica objetivou compreender os rituais de cuidado realizados por famílias, durante a preparação para a vivência de parto domiciliar planejado. Participaram 25 famílias, no período de setembro de 2010 a abril de 2011. As técnicas de coleta de dados foram a observação participante e a entrevista. Mediante processos de apreensão, síntese, teorização e recontextualização, emergiram duas categorias: A casa para nascer e Preparando a chegada do bebê. O parto domiciliar é uma experiência construída no âmbito do casal grávido. A casa é concebida pelas famílias como um local sagrado para a vivência de uma experiência que agregue valores existenciais ao ato fisiológico do nascimento. Compreender esses rituais contribui para o oferecimento de cuidado de enfermagem culturalmente congruente.

Reflexão sobre vivência de cuidados paliativos: óscar e a senhora cor-de-rosa

Directory of Open Access Journals (Sweden)

Ernestina Maria Batoca Silva

2016-02-01

É nosso objectivo reflectir sobre os desafios dos cuidados paliativos pediátricos, contribuir para a construção de um pensamento ético coerente no zelar pelo respeito da dignidade humana, e também contribuir para a compreensão da vivência da criança doente no hospital e seu confronto com a morte, através do sentido e do vivido por uma criança com leucemia.

Diagnosis of Catalyst Cooler and Riser in RFCC using Sealed gamma-ray Source

International Nuclear Information System (INIS)

Kim, Jin Seop; Kim, Jong Bum; Jung, Sung Hee; Kim, Jae Ho

2005-12-01

With a quantitative growth of the petroleum industry, a lot of budget are spent for the maintenance and repairs of facilities related to the process annually. Among them, the RFCC(residual fluid catalytic cracking) is a highly value-added unit which converts gas oil and heavier streams to lighter, more valuable products such as propylene, gasoline by an injection of atmospheric residue into the fluided catalyst. In this study, field experiments were performed to analyze the reasons of an abnormal operation in the catalyst cooler and the catalyst riser belonged to the RFCC unit respectively and to estimate the amount of seriousness using sealed gamma-ray source( 60 Co). The catalyst cooler functions cooling for the regeneration of a catalyst, which will be used to a new media in the RFCC unit. The catalyst riser, while, plays an important part in transporting to next cyclotron steps by mixing of an oil, steam and a catalyst mechanically. The purposes of this study is what was the condition of catalyst flow pattern and whether the coke was produced in an inside process or not. Gamma radiation counts were measured by the detector(NaI) positioned outside the pipe-wall diametrically opposite to the gamma source with a regular space. From the results, the section different from the distribution pattern of nearby catalyst in a facility was found. And this became the definitive information to a process operator. Diagnosis technique using gamma radiation source is proved to be the effective and reliable method in providing information on the media distribution in a facility

Influence of riser-induced slugs on the downstream separation processes

DEFF Research Database (Denmark)

Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

2017-01-01

In Oil & Gas installations the severe slug is an undesired flow regime due to the negative impact on the production rate and facility safety. This study will evaluate the severe riser-induced slugs’ influence to a typical separation process, consisting of a 3-phase gravity separator physically...... linked to a de-oiling hydrocyclone, based on experimental tests performed on a laboratory testing facility. Several scenarios are compared, while three PID controllers’ coefficients are kept constant for all the tests: The separator pressure, water level, and hydrocyclone pressure-drop-ratio (PDR......) controllers. Each respective scenario makes a comparison between uncontrolled, open-, and closed-loop anti-slug control configurations. It is concluded that both open- and closed-loop anti-slug control strategies improve the water level and PDR setpoint tracking equally well, but that the closed-loop strategy...

The Architecture and Beyond of Tread and Riser

Directory of Open Access Journals (Sweden)

Sai Sanath

2016-01-01

The primary constitution of stairs is the arrangement of horizontal and vertical measures known as tread and riser. This is the simplest arrangement that essentially conveys people from one level to the other with required comfort and safety. Steps are a universal symbol with multiple interpretations. They are the most generally used similes in art, philosophy and psychology. Stairs occupy a unique status in the built environment because they not only convey people, but also symbolize the psychological, spiritual and artistic aspects of human nature. The mental significance and symbolic connotations of steps are deeply rooted. Understanding the role of stairs in different spheres of human need and expression is crucial in approaching its design. The pattern of stairs is dependent on the type of materials and other related design considerations. It is one of the unique architectural entities that reflect the various facets of social, psychological, artistic, metaphysical and religious dimensions. The importance of physical activity in the rising sedentary life styles is linked to the design of building elements, especially the staircases. The advancement in technology has displaced the role of stairs into an inconsequential means of emergency escape. But the importance of physical activity in the rising sedentary lifestyle has revitalized the concept of stairs as an active building component. The mono functional approach to staircases in high-rise buildings, especially as the means of escape in emergency situations, indicates that the design of staircases as multi functional element is still under the confines of design explorations. This paper is an attempt to understand the concept of stairs not only from the evolutionary point of view, but also the associated metaphoric meanings and its emerging multi facet identity. The concept of vertical accessibility in the form of tread and riser arrangement makes stairs a timeless phenomenon. The approach to multi utility

Vivências de mulheres cuidadoras de pessoas idosas dependentes: orientação de gênero para o cuidado

Directory of Open Access Journals (Sweden)

Edmeia Campos Meira

2017-05-01

Full Text Available Resumo Objetivo: Apreender nas lembranças da mulher cuidadora o sentido e o significado das vivências de relação de cuidado na unidade familial com a pessoa idosa dependente em contexto de construção social da identidade de gênero orientado para o cuidado. Métodos: Estudo fundamentado na História Oral de Vida com seis mulheres cuidadoras de famílias com pessoas idosas dependentes, no interior da Bahia, Brasil. As lembranças, captadas por entrevista gravada e transcrita, compuseram o corpus de análise. Resultados: O papel social de identidade de gênero direciona a mulher na responsabilização de seus membros familiares dependentes de cuidado, com sentimentos e valores de obrigação humana e forte influência religiosa. Esse cuidado favorece ainda as vivências intergeracionais no espaço das relações familiares com aprendizagens significativas. Conclusão: Urge uma compreensão crítica do papel feminino do cuidado, com incentivo à educação intergeracional e de gênero que propiciem novas perspectivas para o cuidado ao idoso dependente.

Prediction of gasoline yield in a fluid catalytic cracking (FCC riser using k-epsilon turbulence and 4-lump kinetic models: A computational fluid dynamics (CFD approach

Directory of Open Access Journals (Sweden)

Muhammad Ahsan

2015-07-01

Full Text Available Fluid catalytic cracking (FCC is an essential process for the conversion of gas oil to gasoline. This study is an effort to model the phenomenon numerically using commercial computational fluid dynamics (CFD software, heavy density catalyst and 4-lump kinetic model. Geometry, boundary conditions and dimensions of industrial riser for catalytic cracking unit are conferred for 2D simulation using commercial CFD code FLUENT 6.3. Continuity, momentum, energy and species transport equations, applicable to two phase solid and gas flow, are used to simulate the physical phenomenon as efficient as possible. This study implements and predicts the use of the granular Eulerian multiphase model with species transport. Time accurate transient problem is solved with the prediction of mass fraction profiles of gas oil, gasoline, light gas and coke. The output curves demonstrate the breaking of heavy hydrocarbon in the presence of catalyst. An approach proposed in this study shows good agreement with the experimental and numerical data available in the literature.

O papel do enfermeiro perante as vivências dos pais de crianças hospitalizadas

OpenAIRE

Pinheiro, Joana Filipa Cardoso

2013-01-01

Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciada em Enfermagem A hospitalização da criança provoca efeitos secundários em toda a dinâmica e estrutura familiar, em especial nos pais que vão vivenciar sentimentos que até então não conheciam. O objectivo deste trabalho foi identificar as vivências dos pais de crianças hospitalizadas e descrever o papel do enfermeiro perante estes pais para os ajudar a enfrentar es...

IODP Expedition 319, NanTroSEIZE Stage 2: First IODP Riser Drilling Operations and Observatory Installation Towards Understanding Subduction Zone Seismogenesis

Directory of Open Access Journals (Sweden)

Sean Toczko

2010-09-01

Full Text Available The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE is a major drilling project designed to investigate fault mechanics and the seismogenic behavior of subduction zone plate boundaries. Expedition 319 is the first riser drilling operation within scientific ocean drilling. Operations included riser drilling at Site C0009 in the forearc basin above the plate boundary fault, non-riser drilling at Site C0010 across the shallow part of the megasplay faultsystem—which may slip during plate boundary earthquakes—and initial drilling at Site C0011 (incoming oceanic plate for Expedition 322. At Site C0009, new methods were tested, including analysis of drill mud cuttings and gas, and in situ measurements of stress, pore pressure, and permeability. These results, in conjunction with earlier drilling, will provide a the history of forearc basin development (including links to growth of the megasplay fault system and modern prism, b the first in situ hydrological measurements of the plate boundary hanging wall, and c integration of in situ stress measurements (orientation and magnitude across the forearc and with depth. A vertical seismic profile (VSP experiment provides improved constraints on the deeper structure of the subduction zone. At Site C0010, logging-while-drilling measurements indicate significantchanges in fault zone and hanging wall properties over short (<5 km along-strike distances, suggesting different burial and/or uplift history. The first borehole observatory instruments were installed at Site C0010 to monitor pressure and temperature within the megasplay fault zone, and methods of deployment of more complex observatoryinstruments were tested for future operations.

A combined wear-fatigue design methodology for fretting in the pressure armour layer of flexible marine risers

OpenAIRE

O'Halloran, S.M.; Shipway, P.H.; Connaire, A.D.; Leen, Sean B.; Harte, A.M.

2017-01-01

This paper presents a combined experimental and computational methodology for fretting wear-fatigue prediction of pressure armour wire in flexible marine risers. Fretting wear, friction and fatigue parameters of pressure armour material have been characterised experimentally. A combined fretting wear-fatigue finite element model has been developed using an adaptive meshing technique and the effect of bending-induced tangential slip has been characterised. It has been shown that a surface dama...

Construction Method Study For Installation Of A Large Riser In A Single-Shell Tank

International Nuclear Information System (INIS)

Adkisson, D.A.

2010-01-01

This study evaluates and identifies a construction method for cutting a hole in a single-shell tank dome. This study also identifies and evaluates vendors for performing the cut. Single-shell tanks (SST) in the 241-C tank farm are currently being retrieved using various retrieval technologies (e.g., modified sluicing). The Hanford Federal Facility Agreement and Consent Order require that the SSTs be retrieved to less than 360 cubic feet of radioactive waste. The current technologies identified and deployed for tank retrieval have not been able to retrieve waste in accordance with the Hanford Federal Facility Agreement and Consent Order. As such, alternative retrieval systems have been proposed and are currently under construction that will have the ability to retrieve waste to this defined level. The proposed retrieval systems will not fit down existing risers. New risers will need to be installed to provide the retrieval systems access to the inside of the SSTs. The purpose of this study is two-fold. The first objective is to identify multiple concrete cutting technologies and perform an initial pre-screening, evaluate the technologies identified for more in-depth analysis, and recommend a technology/methodology for cutting a hole in the tank dome. The identified/pre-screened methods will be evaluated based on the following criteria: (1) Maturity/complexity; (2) Waste generation; (3) Safety; (4) Cost; and (5) Schedule. Once the preferred method is identified to cut the hole in the tank dome, the second objective is to identify, evaluate, and recommend a vendor for the technology selected that will perform the cutting process.

The Effect of Stick Stiffness of Friction Models on the Bending Behavior in Non-Bonded Flexible Risers

OpenAIRE

Dai, Tianjiao; Ye, Naiquan; Sævik, Svein

2017-01-01

This paper investigates the effect of stick stiffness on the bending behavior in non-bonded flexible risers. The stick stiffness was normally implemented in the friction model for calculating the friction stress between layers in such structures. As the stick stiffness may be too small to achieve the plane-surfaces-remain-plane assumption under low contact pressure in some friction models [1], a new friction model was proposed for maintaining the constant stick stiffness in the present work. ...

Roadside Infrastructure for Safer European Roads (RISER) D06: European Best Practice for Roadside Design: Guidelines for Roadside Infrastructure on New and Existing Roads

NARCIS (Netherlands)

Thomson, R.; Fagerlind, H.; Martinez, A.V.; Amenguel, A.; Naing, C.; Hill, J.; Hoschopf, H.; Dupré, G.; Bisson, O.; Kelkka, M.; Horst, A.R.A. van der; Garcia, J.

2006-01-01

The European Commission Directorate General for Transportation and Energy (DGTREN) sponsored a research project to investigate the best practice guidelines for roadside infrastructure. The RISER consortium has compiled the following document which is a synthesis of existing practice in Europe with

Sulfato Complex Formation of V(V) and V(IV) in Pyrosulfate Melts Investigated by Potentiometry and Spectroscopic Methods

DEFF Research Database (Denmark)

Rasmussen, Søren Birk; Eriksen, Kim Michael; Fehrmann, Rasmus

1999-01-01

with the oxo sulfato vanadate equilibria VO(SO4)2,2- + SO4,2- = VO(SO4)3,4- for V(IV) and (VO)2O(SO4)4,4- + 2SO4,2- = 2VO2(SO4)2,3- + S2O7,2- for V(V), and 2VO2(SO4)2,3- + SO2 + SO4,2- 2VO(SO4)3,4- for the V(V)-V(IV) redox reaction in melts saturated with sulfate. Constants for these equilibria have also been...

Dynamic simulation of industrial Fluidized-bed Catalytic Cracking - FCC unit

Energy Technology Data Exchange (ETDEWEB)

Secchi, Argimiro R.; Neumann, Gustavo A.; Trierweiler, Jorge O. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Engenharia Quimica]. E-mail: arge@enq.ufrgs.br; gneumann@enq.ufrgs.br; jorge@enq.ufrgs.br; Santos, Marlova G. [PETROBRAS S.A., Canoas, RS (Brazil). Refinaria Alberto Pasqualini]. E-mail: marlova@petrobras.com.br

2000-07-01

In this work a mathematical model for the dynamic simulation of the Fluidized-bed Catalytic Cracking (FCC) Reactor, to be used in the analysis, control, and optimization of this system is developed. Based on the full range of published data in FCC performance and kinetic rates, and adapted to the industrial unit of the PETROBRAS' Alberto Pasqualini Refinery (REFAP), an integrated dynamic model is build up. The model is sufficiently complex to capture the major dynamics effects that occur in this system. The regenerator is modeled as emulsion and bubble phases that exchange mass and heat. The riser is modeled as an adiabatic plug flow reactor. The fluid dynamic is taking into account for the catalyst circulation, and the dynamics of the gas phase and the riser are also considered into the model. The model, represented by a non-linear system of differential-algebraic equations, was written in language C and implemented in MATLAB/SIMULINK. The results are compared with the data obtained from the industrial plant of REFAP. (author)

Numerical Investigation of Hydrodynamic Instabilities in Singing Risers Investigation numérique des instabilités hydrodynamiques de risers chantants

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Brac J.

2012-09-01

Full Text Available Offshore transportation of gaseous fluids frequently relies on flexible pipes. Flexible pipes are obtained from the helicoidal rolling of steel tape which induces a geometrical cavity from edge to edge. Along the pipe, the gas infinitely encounters the edge to edge cavity of the same shape at regular interval. In some service conditions, acoustic vibrations of huge amplitude can arise. Indeed, in front of each cavity, there is a shear layer where Kelvin-Helmholtz instability can occur. The flow encounters a large number of cavities on its path which gives rise to a new specific problem: is there a stabilized flow? Results of large eddy scale simulations are presented as a reference but they are very costly. This gives reason to develop a numerical solution of the Orr-Sommerfeld equation in order to analyze the temporal and spatial wave lengths generated by the shear layers in front of the cavities. First, we introduce the problem of flexible risers and the analysis of some RANS and LES modeling. Second, a bibliographical study describes the state of the art about vibrations induced by cavity. Third, we state the Orr-Sommerfeld equation and set the problem we want to solve in terms of generalized eigen values Numerical discretizations are based on finite difference approaches of fourth orders. The choice of the relevant eigen values among all those provided by the solutions of the numerical problem is the main difficulty to be tackled. Le transport offshore de gaz utilise souvent des conduites flexibles. Elles sont fabriquées en enroulant en hélice un ruban d’acier; au contact bord à bord des tours d’hélice, une cavité apparaît. Le gaz s’écoule en conduite et rencontre cette cavité à intervalles réguliers, toujours avec la même forme. Dans certaines conditions d’usage, des vibrations acoustiques de grandes amplitudes apparaissent. En effet, devant chaque cavité, il y a une couche de cisaillement où une instabilité de type

Use of riser tube rotation equipment in the Emlichheim and Landau petroleum mines of Wintershall AG Erdoelwerke; Einsatz von Steigrohrdrehvorrichtungen in den Erdoelfoerderbetrieben Emlichheim und Landau der Wintershall AG Erdoelwerke

Energy Technology Data Exchange (ETDEWEB)

Caspari, R. [Wintershall AG Erdoelwerke, Emlichheim (Germany)

1998-12-31

Riser tube rotation equipment has been in use in the Emlichheim and Landau petroleum wells since 1994 in order to ensure longer life of the riser tubes. (orig.) [Deutsch] In den von Wintershall operierten Erdoelfoerderbetrieben Emlichheim und Landau werden ca. 90% der Bohrungen mit Gestaengetiefpumpen gefoerdert. Aufgrund der lagerstaettentechnischen Gegebenheiten, der Thermalmassnahmen in Emlichheim und der Infrastruktur der Betriebe koennen andere Foerderhilfsmittel wie Tauchkreiselpumpe, Excenterschneckenpumpe oder Gasliften nur bedingt zum Einsatz kommen. Ein wesentlicher Faktor fuer den wirtschaftlichen Betrieb dieser Bohrungen sind die Aufwaeltigungen zur Beseitigung von Schaeden an der Tiefpumpe, dem Pumpgestaenge und den Steigrohren. Waehrend die Einsatzdauer der Tiefpumpen und des Pumpgestaenges durch hoeherwertige Materialguete und geeignete Optimierungsmassnahmen erhoeht werden konnten, sind die Standzeiten der Steigrohre nahezu unveraendert geblieben. Um diese zu erhoehen, werden in den Erdoelfoerderbetrieben Emlichheim und Landau seit April 1994 Steigrohrdrehvorrichtungen eingesetzt. (orig.)

Vivência de mulheres que se submeteram à gastroplastia

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Glenda Agra

2009-12-01

Full Text Available A gastroplastia reduz as co-morbidades e melhora a qualidade de vida, resgatando a auto-estima e inclusão social doobeso mórbido. O estudo teve como objetivo investigar a vivência de mulheres que se submeteram à gastroplastia, apartir de seus discursos. Trata-se de um estudo exploratório com abordagem qualitativa, do qual participaram 16pacientes mulheres que se submeteram à cirurgia bariátrica. Os dados foram coletados nos meses de junho a julho de2007, por meio da técnica de entrevista semi-estruturada, com a utilização do sistema de gravação, as quais foramanalisadas qualitativamente, à luz da técnica do Discurso do Sujeito Coletivo. Emergiram as seguintes idéias centrais:elevação da auto-estima e bem-estar psicológico; promoção de bem-estar físico; mudança negativa no pós-operatórioimediato e mediato; mudança positiva após a fase de adaptação; possibilidade de maior socialização; satisfaçãofamiliar e pessoal enquanto mulher e maior disposição, segurança e melhor estado de humor. Conclui-se, portanto,que, a gastroplastia é um tratamento cirúrgico para obesos mórbidos, que remete à perda ponderal, melhora a autoestima,mas que traz conseqüências negativas. Daí a importância do cuidar destas pacientes desde a decisão de sesubmeter à cirurgia até a total reabilitação.

Perda e luto: vivências de mulheres que interromperam a gestação por malformação fetal letal

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Elenice Bertanha Consonni

2013-09-01

Full Text Available O presente estudo teve por objetivo conhecer as vivências de luto de mulheres que interromperam a gestação sob autorização judicial, devido à malformação fetal incompatível com a vida. Participaram do estudo dez mulheres atendidas no Setor de Medicina Fetal do Hospital das Clínicas de Botucatu. Para coleta dos dados foi realizada entrevista semiestruturada quarenta dias após a interrupção. As entrevistas foram audiogravadas, transcritas na íntegra e tiveram os dados analisados na perspectiva da análise temática de conteúdo. Os resultados revelaram que as mães buscaram explicações e significados para a perda, sendo muito frequentes respostas religiosas e autoculpabilizantes. Os relatos marcaram sentimentos de tristeza, saudade e sensação de vazio pela perda do filho, revelando também a necessidade das mães de manterem-se ligadas a ele. As mães estavam e continuaram vinculadas aos seus filhos e a interrupção da gestação, embora tenha sido uma escolha para minimizar a dor de uma perda inevitável, não as poupou de vivências de grande sofrimento. O estudo traz subsídios para a discussão e planejamento de abordagens e cuidados com a saúde de mulheres que interrompem a gestação por malformação fetal letal, mediante autorização judicial.

Mastery of innovation risk in deep sea developments (part 1) - Drilling and well - round table no.4; Maitrise du risque de l'innovation dans le developpement en grand fond (1. partie) - le forage et le puits - table ronde no.4

Energy Technology Data Exchange (ETDEWEB)

Charlez, Ph.A.; Lassus Dessus, J.; Gazaniol, D. [TotalFinaElf, La Defense, 92 - Courbevoie (France); Guesnon, J. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Hudson, W. [DORIS Engineering, 75 - Paris (France); Chauvin, H. [Geoservices S.A., 93 - Le Blanc Mesnil (France)

2003-02-01

This round table comprises 5 articles dealing with: 1) - the specific problems and drilling risks in very deep waters: risers (diameter, length, volume and weight), sea bottom conditions (high pressure and low temperature), and management of drilling mud weight (pore and fracturing pressures window, mud hydrates formation); 2) - the implementation of risers in very deep waters: risers mechanical properties (tension, weight), stresses on connected and non-connected risers, possible improvements (reduction of mud and riser weights), steel/composite technology for safety lines, lack of knowledge in the implementation of risers (vibrations, fatigue sources, simulation codes, optimization), instrumentation system for risers; 3) - drilling with surface BOP (blow out preventers): advantages and domains of use, risk management; 4) - safety using gas measurement in very deep drilling: detection of gas events (H{sub 2}S, alkanes, CO{sub 2}, benzene, toluene, xylene) during well drilling, improvement of detectors, implementation, reliability; 5) - Girassol field drillings and completions: contractual strategy, wells design, productivity, drilling and completion, underwater systems. (J.S.)

(InVisibilidade da Vivência Homoparental Feminina: entre Preconceitos e Superações

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Aline Nogueira de Lira

Full Text Available Resumo Este artigo teve como objetivo investigar a ambiguidade quanto à (invisibilidade das vivências homoparentais femininas no cenário brasileiro: situações em que o preconceito se revela com crueldade; e, por outro lado, situações em que as mulheres superam esta discriminação e assumem as suas orientações afetivo-sexuais, bem como o projeto de ser mãe. Foram entrevistadas quatro mulheres que se assumem como lésbicas e têm filhos e a entrevista aberta foi o instrumento utilizado para colher os dados. A análise de conteúdo das entrevistas evidenciou que as famílias homoparentais chefiadas por lésbicas vivem um momento paradoxal em relação aos direitos humanos da população LGBT. Por um lado, verificam-se diversas expressões de preconceito e violência homofóbica na vida dessas mulheres; mas, por outro, também são relatadas circunstâncias em que as mulheres superaram esta discriminação e assumem as suas orientações afetivo-sexuais, bem como o projeto de ser mãe.

Espacialidades tecnológicas e vivências urbanas

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Fábio Duarte

2008-11-01

Full Text Available Neste ensaio, discutiremos como os meios tecnológicos de comunicação contemporâneos vêm propiciando a construção de novas vivências espaciais. A análise é pautada por quatro das principais manifestações contemporâneas de construção de espacialidades tecnológicas no meio urbano: a inserção de dispositivos de recorte imagético, que visam sobretudo ao controle de determinados fragmentos espaciais, como as câmeras de vigilância; a visão externa, permanente e total, que alimenta um simulacro extremamente codificado do espaço observado, como os mapas georreferenciados de imagens de satélite; a construção de espaços virtuais, com base nos códigos computacionais, que, mesmo ao tomarem a cidade como referência por similaridade imagética, são alheios às suas propriedades constitutivas e organizativas e a infiltração de meios tecnológicos na cidade, formando, mais do que nichos de realidade virtual, portas e pontes onde se expõem a influências múltiplas e constitutivas os ambientes urbanos e os informacionais. Palavras-chave cidade, meios de comunicação, tecnologias de informação, espaços virtuais Abstract In this essay, I propose to discuss how contemporary communication and information technologies can construct new kinds of spatial experiences. The analysis is based on four main types of urban espatialities built upon technological innovations: media inserted in the cities to control the urban life, such as surveillance cameras; maps based on satellite images which intend to show a total representation of reality; the construction of virtual spaces, based on digital codes which, even when they look like the cities, do not share their intrinsic properties; and the infiltration of the city by technological media which, more then spots of virtual reality, transform the urban environment into a hybrid city. Key words cities, media, information technologies, virtual spaces

Multiphase flow simulation in an annulus configuration

OpenAIRE

Friedemann, Christopher; Mortensen, Mikael; Nossen, Jan

2017-01-01

On the 20th of April 2010, explosion and fire killed 11 people on the Deepwater Horizon oil rig in the Gulf of Mexico. After two days in flames, the rig sank and left the riser (the pipe going up from the seabed) on the sea floor leaking oil and gas from the well through the gap between the drilling riser and the drill-string (rod holding the drillbit) inside it. The accident is known as the Macondo accident. Immediate concerns were raised regarding the amount of oil being released into the G...

O significado e a vivência do abandono familiar para presidiárias = The meaning and the experience of abandonment to family prisoners

OpenAIRE

Jesus, Amanda Costa Freitas de; Oliveira, Lannuzya Veríssimo e; Oliveira, Eloide André; Brandão, Gisetti Corina Gomes; Costa, Gabriela Maria Cavalcanti

2015-01-01

Objetivo: Compreender o significado e a vivência do abandono familiar para presidiárias. Materiais e Métodos: Trata-se de um estudo qualitativo descritivo e exploratório realizado em duas penitenciárias femininas da Paraíba, no período de julho a outubro de 2013. Para coleta de dados foram utilizados um questionário sociodemográfico e uma entrevista semiestruturada realizada com 13 presidiárias. Os dados foram analisados conforme técnica da Análise de Conteúdo. Resultados: Duas categorias for...

Vivências académicas dos estudantes do curso de Licenciatura em Enfermagem: contributos para a intervenção comunitária

OpenAIRE

Costa, Hugo Manuel Ventura

2015-01-01

Dissertação de Mestrado em Enfermagem Comunitária Introdução: O número de estudantes no sistema de ensino superior em Portugal tem aumentado consideravelmente nos últimos anos, refletindo uma progressiva tomada de consciência da importância de se investigar as circunstâncias e os acontecimentos que os estudantes vivenciam e que influenciam o seu percurso académico. Neste contexto, o estudo centrou-se na análise das vivências académicas dos estudantes do curso de licenciatura em enfermagem ...

Monitoring catalyst flow rate in a FCC cold pilot unity by gamma ray transmission measurements

International Nuclear Information System (INIS)

Brito, Marcio F.P.; Netto, Wilson F.S.; Miranda, Marcia V.F.E.S.; Junior, Isacc A.S.; Dantas, Carlos C.; Melo, Silvio B.; Lima, Emerson A.O.

2013-01-01

A model for monitoring catalyst mass flow in riser of Fluid Catalytic Cracking - FCC, pilot unity as a function of air flow and solid injection is proposed. The fluidized FCC- catalyst bed system is investigated in an experimental setup the Cold Pilot Unity - CPU by means of gamma ray transmission measurements. Riser in CPU simulates the reactor in FCC process. By automation control air flow is instrumentally measured in riser and the solid injection is manually controlled by valve adjusting. Keeping a constant solid injection, catalyst level at the return column was measured by gamma transmission for several air flow values in riser. The operational condition reached a steady state regime before given to setup a new air flow value. A calibration of catalyst level as a function of air flow in riser is calculated, therefore, a model for solid feed rate is derived. Recent published work evaluates solid concentration in riser of the CPU by means of gamma ray transmission, and a correlation with air velocity is obtained. In this work, the model for solid feed rate was further investigated by carrying out experiments to measure catalyst concentration at the same air flow values. These experiments lead to a model for monitoring catalyst flow in riser as function of solid feed rate and air flow. Simulation with random numbers produced with Matlab software allows to define validation criteria for the model parameters. (author)

Vivência tecnológica na educação básica: uma estratégia para o ensino e aprendizagem de professores e alunos

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Giseli S Lucas

2017-11-01

Full Text Available O objetivo deste artigo é discutir se as aulas de Vivência Tecnológica, ministradas aos alunos do Ensino Fundamental I, da rede do Serviço Social da Indústria de São Paulo SESI/SP, é uma estratégia pedagógica que auxilia os docentes no processo de ensino e aprendizagem e os alunos na autonomia digital. É notória a tendência do uso cada vez mais frequente de computadores e outras tecnologias na educação escolar; por este motivo, a Vivência Tecnológica foi implantada na rede para potencializar os aspectos didáticos e metodológicos para o ensino e aprendizagem. Por essa razão, esta pesquisa objetiva analisar a dinâmica deste momento de “Vivência Tecnológica”, que recebe o subsídio da teoria construtivista e contribuições de duas profissionais, e verificar se as aulas no Laboratório de Informática e as montagens e programações no Laboratório de Ciências e Tecnologias, com os recursos de blocos de montagem, contribuem para uma abordagem metodológica de ensino relacionada ao desenvolvimento do pensar, do raciocinar, da resolução de problemas, das práticas de leitura e escrita. E ainda, verificar se esta estratégia pode ser referenciada como estratégia pedagógica significativa. A pesquisa buscou o entendimento das relações entre as duas profissionais, identificando a articulação entre o material de ensino, as aulas de informática e as aulas regulares na sala de aula do primeiro ano. Este trabalho possibilitou o aprofundamento das características utilizadas, avaliando a qualidade da relação e socialização entre estas duas esferas formativas para o aluno do primeiro ano do ensino fundamental, identificando os procedimentos metodológicos, e, ainda, investigando a profissionalização dos agentes educacionais, assim como sua formação.

Vivências de Discriminação e Resistência de uma Prostituta Negra

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Raquel de Freitas Banuth

Full Text Available Resumo Este estudo teve por objetivo compreender as vivências de exclusão, discriminação e resistência de uma profissional do sexo negra, que trabalhava em uma casa de prostituição do interior de São Paulo. Utilizou-se entrevista semiestruturada e observação participante com uma mulher negra, que trabalhava em uma casa onde todas as outras profissionais eram brancas. A análise de dados foi orientada pelo modelo proposto por Braun e Clarke e abordou as principais categorias temáticas que concernem ao desenvolvimento profissional no universo das profissionais do sexo. Os relatos mostraram que as colegas de trabalho e os clientes empreendiam um processo de marcada exclusão da entrevistada, baseado no fato de ela pertencer a um grupo racial diferente dos demais. Apesar de enfrentar a “exclusão dentro da exclusão”, a participante não legitimou o preconceito do qual era vítima e, para combatê-lo, lançou mão de estratégias para minimizar o impacto que a discriminação racial exercia sobre ela.

O desenvolvimento de competências para a docência segundo a vivência de docentes de um curso de graduação em enfermagem.

OpenAIRE

Inahiá Pinhel

2006-01-01

Este estudo versa sobre o desenvolvimento de competências para a docência segundo a vivência de docentes de um curso de graduação em enfermagem. Busca conhecer quando e como docentes de um curso de graduação de Enfermagem desenvolvem competências para a docência; identificar os conhecimentos e as habilidades desenvolvidas pelos docentes na construção de competências para o ensino de Enfermagem e identificar como intervir nesse processo, por meio da reflexão sobre a profissão docente. Realizad...

Vivência do sofrimento moral na enfermagem: percepção da enfermeira

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Edison Luiz Devos Barlem

2012-06-01

Full Text Available Objetivando conhecer a percepção do sofrimento moral vivenciado, relacionando frequência e intensidade, realizou-se pesquisa Survey, utilizando escala Likert variando de 0 a 6 pontos, com 124 enfermeiras em hospitais do sul do Brasil, no ano de 2008. Mediante questionário autoaplicável e análise fatorial, foram identificados e validados quatro constructos. Os resultados finais foram obtidos através de três diferentes análises: 1 estatística descritiva; 2 análises de variância 3 regressão múltipla. O constructo que apresentou maior intensidade de percepção de vivência do sofrimento moral foi a falta de competência na equipe de trabalho (4,55, seguido pela negação do papel da enfermeira como advogada do paciente (4,30, obstinação terapêutica (3,60 e desrespeito à autonomia do paciente (3,57. Em relação à percepção da frequência do sofrimento moral, destacou-se, novamente, o constructo falta de competência na equipe de trabalho (2,42, seguido da obstinação terapêutica (2,26, negação do papel da enfermeira como advogada do paciente (1,71 e desrespeito à autonomia do paciente (1,42.

O custo da cura: vivências de conforto e desconforto de mulheres submetidas à braquiterapia

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Míbsam Lysia Carvalho Alves Soares

2016-06-01

Full Text Available RESUMO Objetivo: Descrever as vivências de conforto e desconforto de mulheres que se submeteram à braquiterapia para tratamento de câncer do colo uterino. Métodos: Estudo qualitativo, desenvolvido em 2013, embasado na Teoria do Conforto de Kolcaba e realizado por meio de entrevistas semiestruturadas com oito mulheres que concluíram o tratamento há, no mínimo, seis meses. Resultados: Sobressaíram os seguintes desconfortos: dor do procedimento e dos efeitos pós-tratamento, no contexto físico; medo do desconhecido e do sofrimento, falta de acompanhante, estresse por sentir-se constrangida durante o tratamento, baixa autoestima e trauma psicológico pós-terapia, no contexto psicoespiritual. As medidas de conforto consistiram no diálogo com o profissional, administração de medicações e uso da fé e espiritualidade. Conclusão: Os resultados oferecem subsídios para a prática de profissionais de saúde em relação aos confortos e desconfortos que merecem ser alvo de intervenções na assistência à mulher com câncer.

Vivência da obesidade e do emagrecimento em mulheres submetidas à cirurgia bariátrica

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Carlos Alberto Domingues do Nascimento

2013-06-01

Full Text Available O presente estudo objetivou investigar em mulheres submetidas à cirurgia bariátrica os aspectos psicológicos relacionados à sua condição de obesa e ao seu emagrecimento. O método utilizado foi o descritivoexploratório, de abordagem qualitativa. Os dados permitiram, inicialmente, constatar que a obesidade, além de comprometer a saúde física, restringe a vida afetiva e social, pois impõe um autoconceito negativo e inibidor dos vínculos interpessoais. Com o processo de emagrecimento após a cirurgia, observa-se uma acentuada melhora das condições físicas e emocionais, as quais influenciam e são influenciadas pela reformulação positiva do autoconceito. Todavia, o emagrecimento tanto pode acarretar demandas estéticas irrealizáveis como certas vivências de despersonalização, as quais favorecem a desadaptação emocional ou a ocorrência de transtornos psíquicos. Pelas mudanças identitárias que acarreta, a cirurgia exige, preventivamente, o acompanhamento e o apoio psicológico às mulheres que a realizam.

Vivências e Historicidades: tecendo o currículo na educação de jovens e adultos

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Denise de Melo Sotelo

2012-08-01

Full Text Available O presente artigo pretende fazer uma análise histórica da Educação de Jovens e adultos, focando em seu contexto atual e considerando as especificidades dessa clientela, desde a heterogeneidade de faixa etária, diversidade cultural e motivação, bem como as suas necessidades em tempos de contemporaneidade. Faz também uma abordagem quanto à valorização das identidades, das vivências e histórias: de vida de cada indivíduo, como subsídios para a elaboração de um currículo diferenciado e para a praxis pedagógica, com vistas à inclusão e à inserção social. O artigo avalia ainda a importância do professor como mediador desse processo e o papel da formação continuada na construção de um perfil diferenciado do educador dessa modalidade de ensino.

Vivências de sofrimento e prazer no trabalho de gerentes de banco

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Thaís Augusta Cunha de Oliveira Máximo

Full Text Available Este artigo tem por objetivo discutir as vivências de sofrimento e prazer no trabalho de gerentes de bancos públicos e privados da cidade de João Pessoa, Paraíba. Para tanto, a psicodinâmica do trabalho foi utilizada como referência teórica principal, tendo em vista a articulação dos materiais produzidos em campo com o que a abordagem ensina sobre o sujeito no trabalho, especificamente no que diz respeito à relação complexa entre sofrimento, prazer e trabalho. Para as análises apresentadas, consideram-se as transformações no trabalho gerencial e nos modos de gestão e de funcionamento dos bancos ocorridos nas últimas décadas. Foram realizadas 16 entrevistas com pessoas que exerciam gerências gerais ou intermediárias, analisadas através da análise de conteúdo temática. Os resultados evidenciaram que os seguintes elementos se colocam como fonte de prazer ou de sofrimento: o trabalho com clientes e outros funcionários, o reconhecimento ou a ausência de reconhecimento desse trabalho, a estrutura organizacional, a carga de trabalho e a pressão por resultados, a autonomia ou a falta de autonomia para tomar decisões e a remuneração. Tais resultados demonstram que a relação entre a organização do trabalho e o sujeito está em contínuo movimento, em equilíbrio dinâmico.

As vivências de mães de jovens autistas

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Leticia Segeren

2014-03-01

Full Text Available O autismo é caracterizado como uma síndrome comportamental que compromete a interação social, a comunicação e o comportamento. A adolescência é uma fase em que ocorrem mudanças biológicas e psíquicas que podem desencadear dificuldades e conflitos. Estudos têm apontado que para jovens autistas as dificuldades encontradas neste período são mais acentuadas. A pesquisa teve como objetivo investigar as vivências de mães de jovens autistas, buscando identificar as reações iniciais ao diagnóstico de autismo do filho, conhecer as rotinas diárias do jovem e sua família e identificar as dificuldades encontradas na fase da adolescência do filho autista bem como as expectativas das mães em relação ao seu futuro. O estudo consistiu de uma pesquisa qualitativa com a utilização de entrevistas semiestruturadas, realizadas com onze mães de jovens autistas. Os dados coletados foram gravados, transcritos, categorizados e analisados usando-se a técnica de análise temática. Os resultados apontam que o diagnóstico do autismo foi dado de forma abrangente, enfatizando as dificuldades no desenvolvimento da criança. As mães mudaram sua rotina para assumir o cuidado integral do filho. As dificuldades de socialização da criança levaram algumas delas a evitar ambientes sociais para não ter que lidar com preconceito em relação ao filho. As maiores dificuldades encontradas na adolescência estão relacionadas ao amadurecimento sexual do jovem e são decorrentes da falta de informações das mães e agravadas pelo desconhecimento quanto a quem recorrer para obter orientação. A maior agressividade na fase da adolescência dos filhos autistas foi referida como mais um obstáculo que reforçou o isolamento e o preconceito.

Modelling and transient simulation of water flow in pipelines using WANDA Transient software

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P.U. Akpan

2017-09-01

Full Text Available Pressure transients in conduits such as pipelines are unsteady flow conditions caused by a sudden change in the flow velocity. These conditions might cause damage to the pipelines and its fittings if the extreme pressure (high or low is experienced within the pipeline. In order to avoid this occurrence, engineers usually carry out pressure transient analysis in the hydraulic design phase of pipeline network systems. Modelling and simulation of transients in pipelines is an acceptable and cost effective method of assessing this problem and finding technical solutions. This research predicts the pressure surge for different flow conditions in two different pipeline systems using WANDA Transient simulation software. Computer models were set-up in WANDA Transient for two different systems namely; the Graze experiment (miniature system and a simple main water riser system based on some initial laboratory data and system parameters. The initial laboratory data and system parameters were used for all the simulations. Results obtained from the computer model simulations compared favourably with the experimental results at Polytropic index of 1.2.

Modelling of FCC (Fluid Catalytic Cracking) risers with six lumps; Modelo de elevadores de Unidades de Craqueamento Catalitico com cinetica de seis classes

Energy Technology Data Exchange (ETDEWEB)

Baldessar, Fabio; Negrao, Cezar O. Ribeiro; Palu, Claudia [Centro Federal de Educacao Tecnologica do Parana (CEFET-PR), Curitiba, PR (Brazil)

2004-07-01

The current work presents a mathematical model of an ascendant flow vertical reactor (riser) of a Fluid Catalytic Cracking Unit. The two-phase flow (gas-solid) and the cracking reactions are admitted one-dimensional and steady state. Mass, momentum and energy conservation equations are considered for each phase (solid and gas). A six-lump kinetic model is employed to evaluate gasoil, gasoline, GLP, fuel gas, light cycle oil and coke fractions. The model results are compared to experimental values from a pilot plant and to another model found in the literature. The results are in good agreement, showing the model has great potential. (author)

Trajectórias Familiares e Vivências Escolares: Projectos de vida e processos identitários nos descendentes de imigrantes guineenses na Escola Secundária de Odivelas

OpenAIRE

Fati, David Lamine

2017-01-01

Dissertação de Mestrado em Sociologia O tema central desta investigação é a análise das trajectórias pessoais e escolares dos descendentes de imigrantes africanos provenientes da Guiné-Bissau. Com base nesse intuito, realizou-se uma análise das trajectórias migratórias, educativas e sociais dos progenitores de cada um dos nossos entrevistados, visando entrecruzar essas trajectórias com as vivências pessoais e escolares de cada um dos jovens entrevistados a fim de entender em que medida as ...

A Three-Dimensional Numerical Study of Gas-Particle Flow and Chemical Reactions in Circulating Fluidised Bed Reactors

DEFF Research Database (Denmark)

Hansen, Kim Granly

Three-dimensional Computational Fluid Dynamics (CFD) simulations of Circulating Fluidized Beds (CFB's) have been performed. The computations are performed using a 3D multiphase computational fluid dynamics code with an Eulerian description of both gas and particle phases. The turbulent motion...... implemented in the CFD code FLOTRACS-MP-3D. The decomposition reaction is studied in a 3D representation of a 0.254 m i.d. riser, which has been studied experimentally by Ouyang et al. (1993). Comparison between measured and simulated time-averaged ozone concentration at different elevations in the riser...

CFD simulation of CO_2 sorption on K_2CO_3 solid sorbent in novel high flux circulating-turbulent fluidized bed riser: Parametric statistical experimental design study

International Nuclear Information System (INIS)

Thummakul, Theeranan; Gidaspow, Dimitri; Piumsomboon, Pornpote; Chalermsinsuwan, Benjapon

2017-01-01

Highlights: • Circulating-turbulent fluidization was proved to be advantage on CO_2 sorption. • The novel regime was proven to capture CO_2 higher than the conventional regimes. • Uniform solid particle distribution was observed in the novel fluidization regime. • The system continuity had more effect in the system than the process system mixing. • Parametric experimental design analysis was studied to evaluate significant factor. - Abstract: In this study a high flux circulating-turbulent fluidized bed (CTFB) riser was confirmed to be advantageous for carbon dioxide (CO_2) sorption on a potassium carbonate solid sorbent. The effect of various parameters on the CO_2 removal level was evaluated using a statistical experimental design. The most appropriate fluidization regime was found to occur between the turbulent and fast fluidization regimes, which was shown to capture CO_2 more efficiently than conventional fluidization regimes. The highest CO_2 sorption level was 93.4% under optimized CTFB operating conditions. The important parameters for CO_2 capture were the inlet gas velocity and the interactions between the CO_2 concentration and the inlet gas velocity and water vapor concentration. The CTFB regime had a high and uniform solid particle distribution in both the axial and radial system directions and could transport the solid sorbent to the regeneration reactor. In addition, the process system continuity had a stronger effect on the CO_2 removal level in the system than the process system mixing.

Mapas de Significados Espaciais e Vivência Geracional de Homens e Mulheres Nikkeys de Maringá e Londrina, Paraná. DOI: 10.5212/Rlagg.v.6.i1.0005

OpenAIRE

Kataoka, Caio Shigueharu; Universidade Estadual de Ponta Grossa; Ornat, Marcio Jose; Universidade Estadual de Ponta Grossa

2014-01-01

Este artigo problematiza a relação entre os mapas de significados espaciais e a vivência geracional de homens e mulheres nikkeys no Norte do Paraná. Nosso recorte espacial refere-se às cidades de Maringá e Londrina, tendo visto o fato de apresentarem tanto considerável população relativa de japoneses, quanto expressiva manifestação cultural, organizada segundo Associações Culturais e Esportivas. O campo realizado evidencia os diferentes mapas de significados espaciais constituídos por homens ...

Vivências paternas durante a hospitalização do recém-nascido prematuro na Unidade de Terapia Intensiva Neonatal

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Luciano Marques dos Santos

2012-10-01

Full Text Available Este estudo objetivou compreender as vivências paternas durante a hospitalização do recém-nascido prematuro na Unidade de Terapia Intensiva Neonatal de um hospital público de Feira de Santana, Bahia. Trata-se de um estudo descritivo, exploratório e qualitativo, aprovado por Comitê de Ética em Pesquisa e realizado com nove pais, na Unidade de Terapia Intensiva Neonatal de um hospital público. Os dados foram analisados através da Análise de Conteúdo, os quais apontaram que os partos prematuros causam sentimentos de surpresa, angústia e medo nos pais. É preciso repensar como ocorre a inserção dos pais do prematuro no processo de hospitalização, bem como mudanças nas rotinas estabelecidas para a visita e participação paterna no contexto do cuidado ao prematuro.

The modeling of quadratic B-splines surfaces for the tomographic reconstruction in the FCC- type-riser

International Nuclear Information System (INIS)

Vasconcelos, Geovane Vitor; Dantas, Carlos Costa; Melo, Silvio de Barros; Pires, Renan Ferraz

2009-01-01

The 3D tomography reconstruction has been a profitable alternative in the analysis of the FCC-type- riser (Fluid Catalytic Cracking), for appropriately keeping track of the sectional catalyst concentration distribution in the process of oil refining. The method of tomography reconstruction proposed by M. Azzi and colleagues (1991) uses a relatively small amount of trajectories (from 3 to 5) and projections (from 5 to 7) of gamma rays, a desirable feature in the industrial process tomography. Compared to more popular methods, such as the FBP (Filtered Back Projection), which demands a much higher amount of gamma rays projections, the method by Azzi et al. is more appropriate for the industrial process, where the physical limitations and the cost of the process require more economical arrangements. The use of few projections and trajectories facilitates the diagnosis in the flow dynamical process. This article proposes an improvement in the basis functions introduced by Azzi et al., through the use of quadratic B-splines functions. The use of B-splines functions makes possible a smoother surface reconstruction of the density distribution, since the functions are continuous and smooth. This work describes how the modeling can be done. (author)

EVALUACIÓN MICROMAGNÉTICA DEL NIVEL DE TENSIONES EN ALAMBRES DE TRACCIÓN DE RISERS FLEXIBLES

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JOSÉ MATOS

2013-01-01

Full Text Available En el presente trabajo se describe el uso de un método no destructivo que combina las medidas de los parámetros micromagnéticos para cuantificar las tensiones durante los ensayos de tracción en alambres que componen la armadura estructural de risers flexibles. Este método consideró las técnicas de análisis armónico del campo magnético tangencial, análisis de ruido Barkhausen y el análisis del incremento de la permeabilidad, mediante el ensayo de tracción con carga controlada. Se utiliza la regresión lineal de multiparámetros para analizar los datos de cada técnica en forma individual y en conjunto, con el objetivo de correlacionar los valores conocidos de las cargas con los valores medidos en los ensayos realizados. Los resultados muestran una buena relación de los valores obtenidos mediante el método micromagnético y las cargas aplicadas a los cuerpos de prueba, demostrando la eficacia de la técnica en estas aplicaciones.

Paternidade: vivências de pais de meninos diagnosticados com distrofia muscular de Duchenne

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Silvana Aparecida de Lucca

Full Text Available Resumo Este trabalho teve como objetivo conhecer a vivência da paternidade em pais de filhos com diagnóstico de Distrofia Muscular de Duchenne (DMD. Participaram oito pais cujos filhos possuem diagnóstico confirmado de DMD, com idade acima dos dez anos e residentes em Ribeirão Preto e cidades circunvizinhas. Foram realizadas entrevistas com a utilização de um roteiro semiestruturado e os dados foram analisados com base na análise temática de conteúdo. Os resultados mostram que a notícia da confirmação do diagnóstico de DMD desencadeou uma reação de choque, coexistindo com sentimentos de tristeza, impotência e desesperança. A maioria dos pais considera a enfermidade do filho como missão enviada por Deus, desse modo diminuindo a dor e a angústia causadas pelo adoecimento. Os pais experimentam, desde a percepção dos sintomas da doença, inúmeras perdas que os expõem a grande sofrimento e deflagram o processo de luto antecipatório. Os pais atribuíram à paternidade o significado de missão a ser cumprida e o significado de “paternidade especial” influenciou positivamente na adaptação à doença. Conhecer e compreender como os pais vivenciam a paternidade na presença de uma doença crônica/deficiência é fundamental para programas de acompanhamento psicológico e assistência para os pais e toda a família.

Gênero, violência e viver na rua: vivências de mulheres que fazem uso problemático de drogas

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Márcia Rebeca Rocha de Souza

Full Text Available RESUMO Objetivo Descrever vivências de mulheres, em situação de rua, que fazem uso problemático de drogas. Método Pesquisa qualitativa cujos dados foram produzidos por entrevista semiestruturada realizada com sete mulheres matriculadas em um CAPSad em Salvador-BA, no período de outubro a dezembro de 2012. Resultados A análise de conteúdo temática foi adotada para organização dos dados, emergindo desse processamento duas categorias temáticas: Gênero, violência e uso de drogas: O que muda e o que se perpetua na vida de mulheres usuárias; Sem lenço e sem documento: o viver na rua. Conclusão Os resultados revelam a reprodução de condutas vivenciadas no contexto familiar e de construções sociais que mantêm as mulheres em situação de vulnerabilidade para agravos sociais e de saúde, dentre eles o início e a manutenção do uso problemático de drogas.

Progress Report on Computational Analyses of Water-Based NSTF

Energy Technology Data Exchange (ETDEWEB)

Lv, Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Kraus, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Hu, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Bucknor, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Lisowski, D. [Argonne National Lab. (ANL), Argonne, IL (United States); Nunez, D. [Argonne National Lab. (ANL), Argonne, IL (United States)

2017-08-01

CFD analysis has been focused on important component-level phenomena using STARCCM+ to supplement the system analysis of integral system behavior. A notable area of interest was the cavity region. This area is of particular interest for CFD analysis due to the multi-dimensional flow and complex heat transfer (thermal radiation heat transfer and natural convection), which are not simulated directly by RELAP5. CFD simulations allow for the estimation of the boundary heat flux distribution along the riser tubes, which is needed in the RELAP5 simulations. The CFD results can also provide additional data to help establish what level of modeling detail is necessary in RELAP5. It was found that the flow profiles in the cavity region are simpler for the water-based concept than for the air-cooled concept. The local heat flux noticeably increases axially, and is higher in the fins than in the riser tubes. These results were utilized in RELAP5 simulations as boundary conditions, to provide better temperature predictions in the system level analyses. It was also determined that temperatures were higher in the fins than the riser tubes, but within design limits for thermal stresses. Higher temperature predictions were identified in the edge fins, in part due to additional thermal radiation from the side cavity walls.

Monitoring of mass flux of catalyst FCC in a Cold Pilot Unit by gamma radiation transmission; Monitoramento da taxa de fluxo do catalisador FCC em uma unidade piloto a frio por medicao de transmissao gama

Energy Technology Data Exchange (ETDEWEB)

Brito, Marcio Fernando Paixao de

2014-09-01

This paper proposes a model for monitoring the mass flow of catalyst FCC - Fluid Catalytic Cracking - in a CPU - Cold Pilot unit - due to the injection of air and solid by gamma radiation transmission. The CPU simplifies the process of FCC, which is represented by the catalyst cycle, and it was constructed of acrylic, so that the flow can be visualized. The CPU consists of riser separation chamber and return column, and simulates the riser reactor of the FCC process. The catalyst is injected into the column back to the base of the riser, an inclined tube, where the compressed air means that there fluidization along the riser. When the catalyst comes in the separation chamber, the solid phase is sent to the return column, and the gas phase exits the system through one of the four cyclones at the top of the separation chamber. The transmission gamma of measures will be made by means of three test sections that have source and detector shielded. Pressure drop in the riser measurements are made through three pressure gauges positioned on the riser. The source used was Am-241 gamma ray with energy of 60 keV, and detector used was a scintillator of NaI (Tl) of 2 {sup x} 2{sup .} Measures the mass flow of catalyst are made by varying the seal of the catalyst, and density of solid in the riser because with the combination of these measures can determine the speed of the catalyst in the riser. The results show that the transmission gamma is a suitable technique for monitoring the flow of catalyst, flow model in CPU is annular, tomography third generation is more appropriate to study the CPU and the density variation in circulation in the CPU decreases linearly with increasing air flow. (author)

Monitoring of mass flux of catalyst FCC in a Cold Pilot Unit by gamma radiation transmission

International Nuclear Information System (INIS)

Brito, Marcio Fernando Paixao de

2014-01-01

This paper proposes a model for monitoring the mass flow of catalyst FCC - Fluid Catalytic Cracking - in a CPU - Cold Pilot unit - due to the injection of air and solid by gamma radiation transmission. The CPU simplifies the process of FCC, which is represented by the catalyst cycle, and it was constructed of acrylic, so that the flow can be visualized. The CPU consists of riser separation chamber and return column, and simulates the riser reactor of the FCC process. The catalyst is injected into the column back to the base of the riser, an inclined tube, where the compressed air means that there fluidization along the riser. When the catalyst comes in the separation chamber, the solid phase is sent to the return column, and the gas phase exits the system through one of the four cyclones at the top of the separation chamber. The transmission gamma of measures will be made by means of three test sections that have source and detector shielded. Pressure drop in the riser measurements are made through three pressure gauges positioned on the riser. The source used was Am-241 gamma ray with energy of 60 keV, and detector used was a scintillator of NaI (Tl) of 2 x 2 . Measures the mass flow of catalyst are made by varying the seal of the catalyst, and density of solid in the riser because with the combination of these measures can determine the speed of the catalyst in the riser. The results show that the transmission gamma is a suitable technique for monitoring the flow of catalyst, flow model in CPU is annular, tomography third generation is more appropriate to study the CPU and the density variation in circulation in the CPU decreases linearly with increasing air flow. (author)

Large Eddy simulation of turbulent flow past a circular cylinder in the subcritical and critical regimes

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyongjun; Yang, Kyung-Soo [Inha University, Incheon (Korea, Republic of)

2017-04-15

Large Eddy simulation (LES) results of turbulent flow past a circular cylinder for the specified Reynolds numbers (Re = 63100, 126000, 252000) are presented. An immersed boundary method was employed to facilitate implementation of a circular cylinder in a Cartesian grid system. A dynamic subgrid-scale model, in which the model coefficient is dynamically determined by the current resolved flow field rather than assigned a prefixed constant, was implemented for accurate turbulence modeling. For better resolution near the cylinder surface and in the separated free-shear layers, a composite grid was used. Flow statistics including mean and rms values of force coefficients and Strouhal number of vortex shedding, are presented. Flow visualization using vorticity or Q contours are also shown. Our results are in better agreement with the MARIN measurements compared with RANS calculations reported in the previous ITTC workshop, confirming that LES is a more appropriate simulation methodology than a RANS approach to predict VIV for marine structures.

Violência institucional: vivências no cotidiano da equipe de enfermagem Violencia institucional: vivencias en el cotidiano del equipo de enfermería Institutional violence: routine experiences of the nursing team

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Ana Maria Ribeiro dos Santos

2011-02-01

Full Text Available Estudo qualitativo que objetivou descrever a vivência dos profissionais da equipe de enfermagem expostos à violência institucional, discutir como essas vivências influem no cotidiano e na organização do serviço e conhecer os eventos causadores dessas atitudes violentas. Os sujeitos foram onze profissionais da equipe de enfermagem. Os dados foram produzidos por meio de entrevista, analisados utilizando técnica de análise temática, organizados nas categorias: vivências de violência na equipe de enfermagem, influência da violência no cotidiano de trabalho e na organização do serviço e fatores causadores de atitudes violentas contra a equipe de enfermagem. Os resultados demonstram que os profissionais encontram-se susceptíveis a atitudes violentas no ambiente de trabalho por permanecerem mais tempo e em maior interação com pacientes e acompanhantesEstudio cualitativo que objetivó describir la vivencia de los profesionales del equipo de enfermería expuestos a la violencia institucional, discutir como esas vivencias influyen en el cotidiano y en la organización del servicio y conocer los eventos causadores de esas actitudes violentas. Los sujetos fueron once profesionales del equipo de enfermería. Los datos fueron producidos por medio de encuesta, analizados utilizando técnica de análisis temática, organizados en las categorías: vivencia de violencia en el equipo de enfermería, influencia de la violencia en el cotidiano de trabajo y en la organización del servicio y factores causadores de actitudes violentas contra el equipo de enfermería. Los resultados demonstran que los profesionales se encuentran susceptibles a actitudes violentas en el ambiente de trabajo por permanecieren más tiempo y en mayor interacción con pacientes y acompañantesThe purpose of this qualitative study was to describe the experience of a professional nursing team exposed to institutional violence, to discuss how these experiences influence

A sharp interface immersed boundary method for vortex-induced vibration in the presence of thermal buoyancy

Science.gov (United States)

Garg, Hemanshul; Soti, Atul K.; Bhardwaj, Rajneesh

2018-02-01

We report the development of an in-house fluid-structure interaction solver and its application to vortex-induced vibration (VIV) of an elastically mounted cylinder in the presence of thermal buoyancy. The flow solver utilizes a sharp interface immersed boundary method, and in the present work, we extend it to account for the thermal buoyancy using Boussinesq approximation and couple it with a spring-mass system of the VIV. The one-way coupling utilizes an explicit time integration scheme and is computationally efficient. We present benchmark code verifications of the solver for natural convection, mixed convection, and VIV. In addition, we verify a coupled VIV-thermal buoyancy problem at a Reynolds number, Re = 150. We numerically demonstrate the onset of the VIV in the presence of the thermal buoyancy for an insulated cylinder at low Re. The buoyancy is induced by two parallel plates, kept in the direction of flow and symmetrically placed around the cylinder. The plates are maintained at the hot and cold temperature to the same degree relative to the ambient. In the absence of the thermal buoyancy (i.e., the plates are at ambient temperature), the VIV does not occur for Re ≤ 20 due to stable shear layers. By contrast, the thermal buoyancy induces flow instability and the vortex shedding helps us to achieve the VIV at Re ≤ 20, lower than the critical value of Re (≈21.7), reported in the literature, for a self-sustained VIV in the absence of the thermal buoyancy. The present simulations show that the lowest Re to achieve VIV in the presence of the thermal buoyancy is around Re ≈ 3, at Richardson number, Ri = 1. We examine the effect of the reduced velocity (UR), mass ratio (m), Prandtl number (Pr), Richardson number (Ri) on the displacement of the cylinder, lift coefficient, oscillation frequency, the phase difference between displacement and lift force, and wake structures. We obtain a significantly larger vibration amplitude of the cylinder over a wide

Vivência do idoso dependente no domicílio: análise compreensiva a partir da historicidade heideggeriana

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Larissa Chaves Pedreira

2012-06-01

Full Text Available Com o envelhecimento da população, aumenta a quantidade de idosos dependentes domiciliar, por consequência de doença crônica ou ônus do envelhecimento. Este estudo trata-se de recorte de tese de doutorado que objetivou compreender os modos de ser do idoso no cuidado familiar. Esse recorte objetiva apresentar a análise compreensiva da unidade de significação: vivencia sua presença, na maioria das vezes, na historicidade imprópria. Para tal, realizou-se pesquisa fenomenológica, pautada na obra Ser e Tempo (Heidegger, com cinco idosos inscritos em dois programas de atenção domiciliar. As entrevistas foram transcritas e lidas para captação dos aspectos ônticos e ontológicos, e formação da unidade de significação. A partir dos discursos, compreendeu-se que aspectos relacionados à situação econômica e familiar, às consequências do AVC, ao acesso aos serviços formais e informais, além de vivências e experiências ao longo da vida, fazem a historicidade desses idosos, interferindo nos seus modos de ser.

Grupo PET-Saúde/Vigilância em Saúde do Trabalhador Portuário: vivência compartilhada

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Maria de Fátima Ferreira Queiróz

2015-12-01

Full Text Available Trata-se de um relato de vivência compartilhada do Grupo PET-Saúde/ Vigilância em Saúde do Trabalhador Portuário, da Universidade Federal de São Paulo – Unifesp e o Centro de Referência em Saúde do Trabalhador – CEREST, de Santos, SP. O objetivo é descrever a experiência desse grupo tutorial e sua contribuição para o fortalecimento de ações de vigilância em saúde do trabalhador de Santos. O trabalho portuário é a temática do PET-Saúde por sua importância no cenário nacional e por sofrer transformações que geram fatores de agravos à saúde dos trabalhadores. As ações são desenvolvidas englobando o CEREST, os serviços da rede de saúde de Santos e a comunidade portuária santista. Observa-se que os participantes têm compartilhado conhecimento teórico e prático profissional, contribuindo nas ações dos trabalhadores do CEREST e apontando na direção de aproximação com a rede básica de atenção à saúde.

Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

Energy Technology Data Exchange (ETDEWEB)

Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-05-01

The full-scale, room-temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer at the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.

Circulating fluidized bed hydrodynamics experiments for the multiphase fluid dynamics research consortium (MFDRC).

Energy Technology Data Exchange (ETDEWEB)

Oelfke, John Barry; Torczynski, John Robert; O' Hern, Timothy John; Tortora, Paul Richard; Bhusarapu, Satish (; ); Trujillo, Steven Mathew

2006-08-01

An experimental program was conducted to study the multiphase gas-solid flow in a pilot-scale circulating fluidized bed (CFB). This report describes the CFB experimental facility assembled for this program, the diagnostics developed and/or applied to make measurements in the riser section of the CFB, and the data acquired for several different flow conditions. Primary data acquired included pressures around the flow loop and solids loadings at selected locations in the riser. Tomographic techniques using gamma radiation and electrical capacitance were used to determine radial profiles of solids volume fraction in the riser, and axial profiles of the integrated solids volume fraction were produced. Computer Aided Radioactive Particle Tracking was used to measure solids velocities, fluxes, and residence time distributions. In addition, a series of computational fluid dynamics simulations was performed using the commercial code Arenaflow{trademark}.

Numerical investigation of the vortex-induced vibration of an elastically mounted circular cylinder at high Reynolds number (Re = 104 and low mass ratio using the RANS code.

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Niaz Bahadur Khan

Full Text Available This study numerically investigates the vortex-induced vibration (VIV of an elastically mounted rigid cylinder by using Reynolds-averaged Navier-Stokes (RANS equations with computational fluid dynamic (CFD tools. CFD analysis is performed for a fixed-cylinder case with Reynolds number (Re = 104 and for a cylinder that is free to oscillate in the transverse direction and possesses a low mass-damping ratio and Re = 104. Previously, similar studies have been performed with 3-dimensional and comparatively expensive turbulent models. In the current study, the capability and accuracy of the RANS model are validated, and the results of this model are compared with those of detached eddy simulation, direct numerical simulation, and large eddy simulation models. All three response branches and the maximum amplitude are well captured. The 2-dimensional case with the RANS shear-stress transport k-w model, which involves minimal computational cost, is reliable and appropriate for analyzing the characteristics of VIV.

A avaliação psicossocial no contexto da adoção: vivências das famílias adotantes

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Costa Liana Fortunato

2003-01-01

Full Text Available Foi realizada uma pesquisa de enfoque qualitativo com duas famílias adotantes, através de entrevista de grupo focal em um serviço de adoção de uma Vara da Infância e da Juventude. De acordo com os participantes, são aspectos essenciais do atendimento: o modo de avaliação; a verdade sobre a filiação ser dita à criança adotada; a vivência de família do casal; a experiência do estudo psicossocial durante o processo de adoção; a necessidade de informação e campanhas de divulgação; o papel do acaso e do divino no acerto da escolha da criança selecionada e a confiança no trabalho técnico. Foi possível concluir que o contexto judiciário pode ser um importante catalisador para a mudança, mas pode também ser precursor de arbitrariedades, especialmente no Brasil, em que ainda se fazem sentir a desigualdade e a falta de cidadania. Em suma, é fundamental entender o judiciário como um contexto de possibilidades, ao invés de um contexto de limites.

Numerical simulation of an elementary Vortex-Induced-Vibration problem by using fully-coupled fluid solid system computation

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M Pomarède

2016-09-01

Full Text Available Numerical simulation of Vortex-Induced-Vibrations (VIV of a rigid circular elastically-mounted cylinder submitted to a fluid cross-flow has been extensively studied over the past decades, both experimentally and numerically, because of its theoretical and practical interest for understanding Flow-Induced-Vibrations (FIV problems. In this context, the present article aims to expose a numerical study based on fully-coupled fluid-solid computations compared to previously published work [34], [36]. The computational procedure relies on a partitioned method ensuring the coupling between fluid and structure solvers. The fluid solver involves a moving mesh formulation for simulation of the fluid structure interface motion. Energy exchanges between fluid and solid models are ensured through convenient numerical schemes. The present study is devoted to a low Reynolds number configuration. Cylinder motion magnitude, hydrodynamic forces, oscillation frequency and fluid vortex shedding modes are investigated and the “lock-in” phenomenon is reproduced numerically. These numerical results are proposed for code validation purposes before investigating larger industrial applications such as configurations involving tube arrays under cross-flows [4].

Catalytic Transformation of Ethylbenzene over Y-Zeolite-based Catalysts

KAUST Repository

Al-Khattaf, Sulaiman

2008-01-01

Catalytic transformation of ethylbenzene (EB) has been investigated over ultrastable Y (USY)-zeolite-based catalysts in a novel riser simulator at different operating conditions. The effect of reaction conditions on EB conversion is reported

Stress and Pore Pressure Measurement in IODP Riser Drilling: An Example from Expedition 319, Kumano Basin offshore SW Honshu, Japan

Science.gov (United States)

Saffer, D. M.; McNeill, L. C.; Byrne, T. B.; Araki, E.; Flemings, P. B.; Conin, M.; Eguchi, N. O.; Takahashi, K.; Toczko, S.; Boutt, D. F.; Doan, M.; Kano, Y.; Ito, T.; Lin, W.

2009-12-01

In summer 2009, Integrated Ocean Drilling Program (IODP) Expedition 319 drilled a 1600 m deep riser borehole (Site C0009) in the Kumano Basin offshore SW Japan, to investigate the properties, structure and state of stress in the hanging wall above the subduction plate boundary. The first riser-based scientific drilling in IODP history allowed us to make several new scientific measurements including in situ stress magnitude, pore pressure and permeability using the Modular Formation Dynamics Tester (MDT) wireline tool, and measurement of minimum stress magnitude from Leak-off Tests (LOT). In addition, continuous monitoring of mud weight, mud gas, annular pressure, and mud losses provided data to constrain formation pore fluid pressure and stress. At Site C0009, we conducted 2 LOTs below a casing shoe at 708.6 m depth and 11 successful MDT measurements, including 9 single probe tests to measure pore pressure and fluid mobility and 2 dual packer tests: 1 to measure permeability by a drawdown test, and 1 to measure in situ stress. Measured pore pressures are approximately hydrostatic to 1463.7 m depth. We observed only minor gas shows when drilling ahead (as in-place methane was liberated from the rock at the bit) but little or no gas during pipe connections. This indicates that the borehole mud pressure exceeded the formation pore pressure, and is consistent with the MDT measurements. Permeabilities range from ~10-16 m2 - 10-14 m2, and the observed variation is consistent with lithologic changes defined in gamma ray logs. The MDT measurement at 874.3 mbsf and the LOT at 708.6 m yield values for the least principal stress of 34.8 MPa and 30.2 MPa, respectively. Both are less than the vertical stress (Sv) computed from density logs. Partial mud circulation losses occurred when the borehole mud pressure exceeded the leak-off stress measured at the base of the casing shoe; this provides an additional indirect constraint on Shmin magnitude. Mud pressure slightly in excess

Two-year outcomes of the Early Risers prevention trial with formerly homeless families residing in supportive housing.

Science.gov (United States)

Gewirtz, Abigail H; DeGarmo, David S; Lee, Susanne; Morrell, Nicole; August, Gerald

2015-04-01

This article reports 2-year outcomes from a cluster randomized, controlled trial of the Early Risers (ER) program implemented as a selective preventive intervention in supportive housing settings for homeless families. Based on the goals of this comprehensive prevention program, we predicted that intervention participants receiving ER services would show improvement in parenting and child outcomes relative to families in treatment-as-usual sites. The sample included 270 children in 161 families, residing in 15 supportive housing sites; multimethod, multi-informant assessments conducted at baseline and yearly thereafter included parent and teacher report of child adjustment, parent report of parenting self-efficacy, and parent-child observations that yielded scores of effective parenting practices. Data were modeled in HLM7 (4-level model accounting for nesting of children within families and families within housing sites). Two years' postbaseline, intent-to-treat (ITT) analyses indicated that parents in the ER group showed significantly improved parenting self-efficacy, and parent report indicated significant reductions in ER group children's depression. No main effects of ITT were shown for observed parenting effectiveness. However, over time, average levels of parenting self-efficacy predicted observed effective parenting practices, and observed effective parenting practices predicted improvements in both teacher- and parent-report of child adjustment. This is the first study to our knowledge to demonstrate prevention effects of a program for homeless families residing in family supportive housing. (c) 2015 APA, all rights reserved).

Estupro e gravidez: Relatos das vivências de mulheres antes e após o desfecho da gestação

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Mykaella Cristina Antunes Nunes

Full Text Available Resumo Investigou-se a experiência de três mulheres que engravidaram resultado de estupro, usuárias de um hospital-maternidade de Fortaleza, Ceará, destacando as vivências anteriores e após o desfecho da gestação (a continuidade ou a interrupção legal. Em dois casos houve a interrupção legal da gestação e em um caso a continuidade, após ter sido negada a concessão para a realização do aborto. Os motivos relacionados à interrupção da gravidez foram: pensamentos e sentimentos negativos em torno da violência, da criança e da perspectiva de vida futura. Após o desfecho, as participantes que interromperam a gestação expressaram o desejo de retomar ou iniciar projetos de vida e no caso da participante que precisou dar continuidade à gestação, sinais de uma possível vinculação afetiva com a criança. Conclui-se que tais experiências necessitam ser conhecidas em seus aspectos de interrupção ou de continuidade da gestação para a melhoria das políticas públicas voltadas para essas mulheres.

A analytical comparison of different estimators for the density distribution of the catalyst in a experimental riser by a gammametric technique

International Nuclear Information System (INIS)

Lima, Emerson Alexandre de Oliveira; Dantas Carlos C.; Melo, Silvio de Barros; Santos, Valdemir Alexandre dos

2005-01-01

In this paper, we solve the following questions: what will be the estimate of the r = r (x, y, z) function format? Which method would describe the density distribution function more precisely? Which is the best estimator? Also, once the ρ=ρ(x, y, z) format and the approximation technique is defined, comes the experimental arrangement and pass length configuration, which are the next problems to be solved. Finding the best parameter estimation for the ρ=ρ(x, y, z) function according to the C pass lengths and their spatial configuration. The latter is required to define the ρ=ρ(x, y, z) function resolution and the mechanical scanning movements of the arrangement. Such definitions will be implemented for an automate arrangement, by a computational program, to further development of the reconstruction of catalyst density distribution on experimental risers.. The precision evaluation was finally compared to the arrangement geometry that yields the best pass length spatial configuration. The results are shown in graphics for the two known density distributions. As a conclusion, the parameters for an automate arrangement design, are given under the required precision for the catalyst distribution reconstruction. (author)

Molecular characterization of cDNAs encoding G protein alpha and beta subunits and study of their temporal and spatial expression patterns in Nicotiana plumbaginifolia Viv.

Science.gov (United States)

Kaydamov, C; Tewes, A; Adler, K; Manteuffel, R

2000-04-25

We have isolated cDNA sequences encoding alpha and beta subunits of potential G proteins from a cDNA library prepared from somatic embryos of Nicotiana plumbaginifolia Viv. at early developmental stages. The predicted NPGPA1 and NPGPB1 gene products are 75-98% identical to the known respective plant alpha and beta subunits. Southern hybridizations indicate that NPGPA1 is probably a single-copy gene, whereas at least two copies of NPGPB1 exist in the N. plumbaginifolia genome. Northern analyses reveal that both NPGPA1 and NPGPB1 mRNA are expressed in all embryogenic stages and plant tissues examined and their expression is obviously regulated by the plant hormone auxin. Immunohistological localization of NPGPalpha1 and NPGPbeta1 preferentially on plasma and endoplasmic reticulum membranes and their immunochemical detection exclusively in microsomal cell fractions implicate membrane association of both proteins. The temporal and spatial expression patterns of NPGPA1 and NPGPB1 show conformity as well as differences. This could account for not only cooperative, but also individual activities of both subunits during embryogenesis and plant development.

Core disruptive accident margin seal

International Nuclear Information System (INIS)

Garin, J.; Belsick, J.C.

1978-01-01

Disclosed is an apparatus for sealing the annulus defined between a substantially cylindrical rotatable first riser assembly and plug combination disposed in a substantially cylindrical second riser assembly and plug combination of a nuclear reactor system. The apparatus comprises a flexible member disposed between the first and second riser components and attached to a metal member which is attached to an actuating mechanism. When the actuating mechanism is not actuated, the flexible member does not contact the riser components thus allowing the free rotation of the riser components. When desired, the actuating mechanism causes the flexible member to contact the first and second riser components in a manner to block the annulus defined between the riser components, thereby sealing the annulus between the riser components

A modified multi-objective particle swarm optimization approach and its application to the design of a deepwater composite riser

Science.gov (United States)

Zheng, Y.; Chen, J.

2017-09-01

A modified multi-objective particle swarm optimization method is proposed for obtaining Pareto-optimal solutions effectively. Different from traditional multi-objective particle swarm optimization methods, Kriging meta-models and the trapezoid index are introduced and integrated with the traditional one. Kriging meta-models are built to match expensive or black-box functions. By applying Kriging meta-models, function evaluation numbers are decreased and the boundary Pareto-optimal solutions are identified rapidly. For bi-objective optimization problems, the trapezoid index is calculated as the sum of the trapezoid's area formed by the Pareto-optimal solutions and one objective axis. It can serve as a measure whether the Pareto-optimal solutions converge to the Pareto front. Illustrative examples indicate that to obtain Pareto-optimal solutions, the method proposed needs fewer function evaluations than the traditional multi-objective particle swarm optimization method and the non-dominated sorting genetic algorithm II method, and both the accuracy and the computational efficiency are improved. The proposed method is also applied to the design of a deepwater composite riser example in which the structural performances are calculated by numerical analysis. The design aim was to enhance the tension strength and minimize the cost. Under the buckling constraint, the optimal trade-off of tensile strength and material volume is obtained. The results demonstrated that the proposed method can effectively deal with multi-objective optimizations with black-box functions.

Vortex-Induced Vibrations of a Square Cylinder with Damped Free-End Conditions

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S. Manzoor

2013-01-01

Full Text Available The authors report the results of vortex-induced vibrations of a square cylinder in a wind tunnel. This constitutes a high mass ratio environment. The square cylinder is mounted in the wind tunnel in such a fashion that it only performs rigid body oscillations perpendicular to the flow direction with damped free-end conditions. This physical situation allows a direct evaluation for analytical models relying on simplified 2D assumptions. The results are also compared with two-dimensional fluid-structure (CFD-CSD numerical simulations. The comparison shows that despite having one-dimensional motion, the analytical model does not predict the VIV region with correctness. Results show that the numerical simulations and experimental results differ from the analytical model for the prediction of reduced velocity corresponding to peak amplitude. Also the analytical reduced velocity envelope is underpredicted compared to both numerical simulations and experimental data despite the structure being lightly damped. The findings are significant as the experimental results for freely oscillating high mass ratio body show differences from the low mass ratio especially in the transition between VIV and galloping regions. However the numerical simulations show comparatively close agreement.

Experimental chaotic quantification in bistable vortex induced vibration systems

Science.gov (United States)

Huynh, B. H.; Tjahjowidodo, T.

2017-02-01

The study of energy harvesting by means of vortex induced vibration systems has been initiated a few years ago and it is considered to be potential as a low water current energy source. The energy harvester is realized by exposing an elastically supported blunt structure under water flow. However, it is realized that the system will only perform at a limited operating range (water flow) that is attributed to the resonance phenomenon that occurs only at a frequency that corresponds to the fluid flow. An introduction of nonlinear elements seems to be a prominent solution to overcome the problem. Among many nonlinear elements, a bistable spring is known to be able to improve the harvested power by a vortex induced vibrations (VIV) based energy converter at the low velocity water flows. However, it is also observed that chaotic vibrations will occur at different operating ranges that will erratically diminish the harvested power and cause a difficulty in controlling the system that is due to the unpredictability in motions of the VIV structure. In order to design a bistable VIV energy converter with improved harvested power and minimum negative effect of chaotic vibrations, the bifurcation map of the system for varying governing parameters is highly on demand. In this study, chaotic vibrations of a VIV energy converter enhanced by a bistable stiffness element are quantified in a wide range of the governing parameters, i.e. damping and bistable gap. Chaotic vibrations of the bistable VIV energy converter are simulated by utilization of a wake oscillator model and quantified based on the calculation of the Lyapunov exponent. Ultimately, a series of experiments of the system in a water tunnel, facilitated by a computer-based force-feedback testing platform, is carried out to validate the existence of chaotic responses. The main challenge in dealing with experimental data is in distinguishing chaotic response from noise-contaminated periodic responses as noise will smear

Trabalho em saúde mental: vivências dos profissionais diante dos resultados Trabajo en salud mental: vivencias de profisionales delante los resultados Mental health work: professional's experiences facing the outcomes

Directory of Open Access Journals (Sweden)

Vinicius Carvalho de Vasconcellos

2012-12-01

Full Text Available Considerando o cenário de consolidação da reforma psiquiátrica brasileira, este artigo investigou, no contexto dos trabalhadores da saúde mental, representações relativas ao papel profissional, às vivências diante dos resultados da assistência e às expectativas do futuro profissional da Saúde, tratando igualmente da possível ligação entre esses elementos. O material empírico foi coletado por meio de oito entrevistas semiestruturadas, realizadas em um Centro de Atenção Psicossocial brasileiro, e analisado principalmente pelo referencial teórico da psicossociologia francesa. De modo geral, os resultados sugerem que a vivência de realização diante dos resultados do trabalho vincula-se ao cumprimento do papel profissional, indicando também a ligação entre esses últimos elementos e as expectativas do futuro profissional. Na discussão e nas considerações finais, ressalta-se a concepção do trabalho por meio de seus limites intrínsecos como mecanismo que atenua a frustração profissional e analisam-se as implicações das vivências relativas aos resultados no vínculo subjetivo dos profissionais com o trabalho.Ante la consolidación de la reforma psiquiátrica brasileña, este trabajo investigó, en el contexto de los trabajadores de la salud mental, las representaciones sobre el papel profesional, las vivencias delante los resultados del cuidado y las expectativas de futuro profesional, abordando también la posible relación entre estos elementos. El material empírico fue recogido a través de ocho entrevistas semiestructuradas llevadas a cabo en un Centro de Atención Psicosocial brasileño y analizado a partir del referencial teórico de la psicossociología francesa. Este análisis mostró que la realización/frustación asociada con los resultados del trabajo está conectada con el cumplimiento del papel profesional y con las expectativas de futuro profesional. La discusión y las observaciones finales acent

Transalkylation of ethyl benzene with triethylbenzene over ZSM-5 zeolite catalyst

KAUST Repository

Akhtar, M. Naseem; Tukur, Nasiru M.; Al-Yassir, Nabil; Al-Khattaf, Sulaiman; Čejka, Jiří

2010-01-01

Transalkylation of 1,3,5-triethylbenzene (TEB) with ethylbenzene (EB) has been studied over ZSM-5 zeolite using a riser simulator reactor with respect to optimizing DEB yield. The reaction temperature was varied from 350 to 500°C with contact time

CIRCUS and DESIRE: Experimental facilities for research on natural-circulation-cooled boiling water reactors

International Nuclear Information System (INIS)

Kruijf, W.J.M. de; Haden, T.H.J.J. van der; Zboray, R.; Manera, A.; Mudde, R.F.

2002-01-01

At the Delft University of Technology two thermohydraulic test facilities are being used to study the characteristics of Boiling Water Reactors (BWRs) with natural circulation core cooling. The focus of the research is on the stability characteristics of the system. DESIRE is a test facility with freon-12 as scaling fluid in which one fuel bundle of a natural-circulation BWR is simulated. The neutronic feedback can be simulated artificially. DESIRE is used to study the stability of the system at nominal and beyond nominal conditions. CIRCUS is a full-height facility with water, consisting of four parallel fuel channels and four parallel bypass channels with a common riser or with parallel riser sections. It is used to study the start-up characteristics of a natural-circulation BWR at low pressures and low power. In this paper a description of both facilities is given and the research items are presented. (author)

Analysis of the Nonlinear Static and Dynamic Behavior of Offshore Structures

KAUST Repository

Alfosail, Feras

2015-07-01

Understanding static and dynamic nonlinear behavior of pipes and risers is crucial for the design aspects in offshore engineering fields. In this work, we examine two nonlinear problems in offshore engineering field: vortex Induced vibration of straight horizontal pipes, and boundary layer static solution of inclined risers. In the first study, we analyze the effect of the internal velocity of straight horizontal pipe and obtain the vortex induced vibration forces via coupling the pipe equation of motion with the recently modified Van Der Pol oscillator governing the lift coefficient. Our numerical results are obtained for two different pipe configurations: hinged-hinged, and clamped- clamped. The results show that the internal velocity reduces the vibration and the oscillation amplitudes. Also, it is shown that the clamped-clamped pipe configuration offers a wider range of internal velocities before buckling instability occurs. The results also demonstrate the effect of the end condition on the amplitudes of vibration. In the second study, we develop a boundary layer perturbation static solution to govern and simulate the static behavior of inclined risers. In the boundary layer analysis, we take in consideration the effects of the axial stretch, applied tension, and internal velocity. Our numerical simulation results show good agreement with the exact solutions for special cases. In addition, our developed method overcomes the mathematical and numerical limitations of the previous methods used before.

Modeling and Control of Underwater Robotic Systems

Energy Technology Data Exchange (ETDEWEB)

Schjoelberg, I:

1996-12-31

This doctoral thesis describes modeling and control of underwater vehicle-manipulator systems. The thesis also presents a model and a control scheme for a system consisting of a surface vessel connected to an underwater robotic system by means of a slender marine structure. The equations of motion of the underwater vehicle and manipulator are described and the system kinematics and properties presented. Feedback linearization technique is applied to the system and evaluated through a simulation study. Passivity-based controllers for vehicle and manipulator control are presented. Stability of the closed loop system is proved and simulation results are given. The equation of motion for lateral motion of a cable/riser system connected to a surface vessel at the top end and to a thruster at the bottom end is described and stability analysis and simulations are presented. The equations of motion in 3 degrees of freedom of the cable/riser, surface vessel and robotic system are given. Stability analysis of the total system with PD-controllers is presented. 47 refs., 32 figs., 7 tabs.

Recursive thoughts on the simulation of the flexible multibody dynamics of slender offshore structures

NARCIS (Netherlands)

Schilder, Jurnan Paul; Ellenbroek, Marcellinus Hermannus Maria; de Boer, A.

2017-01-01

In this work, the floating frame of reference formulation is used to create a flexible multibody model of slender offshore structures such as pipelines and risers. It is shown that due to the chain-like topology of the considered structures, the equation of motion can be expressed in terms of

Measurement of Gas Velocities in the Presence of Solids in the Riser of a Cold Flow Circulating Fluidized Bed

International Nuclear Information System (INIS)

Spenik, J.; Ludlow, J.C.; Compston, R.; Breault, R.W.

2007-01-01

The local gas velocity and the intensity of the gas turbulence in a gas/solid flow are a required measurement in validating the gas and solids flow structure predicted by computational fluid dynamic (CFD) models in fluid bed and transport reactors. The high concentration and velocities of solids, however, make the use of traditional gas velocity measurement devices such as pitot tubes, hot wire anemometers and other such devices difficult. A method of determining these velocities has been devised at the National Energy Technology Laboratory employing tracer gas. The technique developed measures the time average local axial velocity gas component of a gas/solid flow using an injected tracer gas which induces changes in the heat transfer characteristics of the gas mixture. A small amount of helium is injected upstream a known distance from a self-heated thermistor. The thermistor, protected from the solids by means of a filter, is exposed to gases that are continuously extracted from the flow. Changes in the convective heat transfer characteristics of the gas are indicated by voltage variations across a Wheatstone bridge. When pulsed injections of helium are introduced to the riser flow the change in convective heat transfer coefficient of the gas can be rapidly and accurately determined with this instrument. By knowing the separation distance between the helium injection point and the thermistor extraction location as well as the time delay between injection and detection, the gas velocity can easily be calculated. Variations in the measured gas velocities also allow the turbulence intensity of the gas to be estimated

Determination of the catalyst circulation rate in a FCC cold flow pilot unit using nuclear techniques

International Nuclear Information System (INIS)

Santos, Valdemir A. dos; Lima, Emerson A.O.

2013-01-01

Nuclear techniques of gamma transmission and radioactive tracer were used to estimate the catalyst circulation rate in a cold flow pilot plant unit of Fluid Catalytic Cracking (FCC). Catalyst circulation rate in a FCC unit, allow to determine operating conditions of the exchange catalyst and inlet data for fluid dynamic simulation computational program. The pilot unit was fabricated obeying geometrical parameters provided by the Petrobras Research Center (CENPES), based on hot pilot units to existing in that center. The cold flow pilot unit has a transfer line, two separation vessels flash type, a return column, a riser and a regenerator. The vertical sections as riser, return column, regenerator column and transfer line are made of transparent material (glass). The two separation vessels have bases with tapered cylindrical shapes and are made of steel plates. The riser is divided into four sections of different diameters (0.005 m, 0.010 m, 0.018 m and 0.025 m) and rising upwards, to simulate the increasing flow rate caused by the increase of volume with the increase of the number of moles due to molecules breakage. The radioactive tracer used was the catalyst itself (intrinsic tracer) irradiated by neutron activation, yielding the radioisotope 59 Fe. The velocity measurements were also obtained with aid of an electronic clock triggered by certain radiation levels across the two detectors. Besides estimates for the catalyst circulation rate was possible to identify the type of flow relative to the catalyst in return column. (author)

Vivências e percepções dos estágios pedagógicos: estudo com alunos de licenciaturas em ensino Experiences and perceptions during practicum: a study with preservice teachers

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Susana Caires

2003-12-01

Full Text Available Centrado na última etapa da formação inicial de professores - os estágios pedagógicos - o presente trabalho explora alguns dos aspectos mais significativos da estreia na profissão docente. Incidindo na perspectiva dos professores-estagiários, o repertório explorado abarca as principais vivências e percepções associadas ao “tornar-se-professor”, dando a conhecer alguns dos maiores ganhos e dificuldades inerentes a este processo. Tomando as respostas de 229 professores-estagiários da Universidade do Minho no Inventário de Vivências e Percepções de Estágio (Versão para as Licenciaturas em Ensino, aplicado no início e no final do estágio, detectaram-se oscilações positivas na forma como os professores-estagiários vivenciam esta etapa formativa. Entre as cinco dimensões do questionário (“Socialização Profissional e Institucional”, “Aspectos sócio-emocionais”, “Aprendizagem e Desenvolvimento Profissional”, “Apoio/Recursos/Supervisão” e “Aspectos Vocacionais”, destaquem-se os maiores níveis de satisfação e ganho percebidos pelos sujeitos nas dimensões “Socialização Profissional e Institucional”, “Aprendizagem e Desenvolvimento Profissional” e “Aspectos Vocacionais”.Focusing on the last stage of the Initial Teacher Education - the practicum experience/preservice program - this paper explores some of the most significant aspects of the initial teaching experience. Concentrating on preservice teacher’s perspectives, the paper encloses the main experiences and perceptions related to “becoming a teacher”, presenting some of the major gains and difficulties inherent to this process. The answers of a group of 229 student teachers from Minho University to the “Inventory of Experiences and Perceptions at Practicum” (Version for Teacher Education Students, applied at the beginning and at the end of the practicum, showed positive oscillations in the way student teachers live this

Perceções dos(as) psicoterapeutas sobre a influência dos estereótipos de género e das relações íntimas, heterossexuais e não-heterossexuais, nas vivências da disfunção erétil

OpenAIRE

Cunha, Catarina Gradíssimo Dias da

2012-01-01

Dissertação de mestrado integrado em Psicologia (área de especialização em Psicologia Clínica) Esta dissertação constitui-se como um estudo exploratório e descritivo da perceção que os/as psicoterapeutas, com experiência de acompanhamento de casos de Disfunção Erétil, têm acerca do impacto que os estereótipos de género e o funcionamento das relações íntimas têm nas vivências desta disfunção. Para tal, realizaram-se entrevistas semiestruturadas a 9 psicoterapeutas (psicólogos/as...

Examination of hydrodynamic force acting on a circular cylinder in vortex-induced vibrations in synchronization

Energy Technology Data Exchange (ETDEWEB)

Shen, Linwei; Sun, Zhilin [Ocean College, Zhejiang University, Zhoushan, 316021 (China); Chan, Eng-Soon, E-mail: shenlinwei@zju.edu.cn [Department of Civil and Environmental Engineering, National University of Singapore, No. 1 Engineering Drive 2, Singapore 117576 (Singapore)

2017-04-15

An immersed boundary method is employed to simulate vortex-induced vibrations (VIV) of a circular cylinder in two dimensions. The Reynolds number is 150, and the cylinder mass ratios of 2 and 10 are considered. The synchronization regions for these two mass ratios are determined by the simulations. It is found that the cycle-averaged added mass is about zero at the reduced velocity of 6.1. The instantaneous frequency, which is obtained by Hilbert transformation of the cylinder oscillating displacement, exhibits an important feature whereby the cylinder oscillation in the VIV synchronization region is modulated with a frequency twice the displacement prevailing frequency. The cylinder displacement could still be well approximated by a sine function with a constant frequency and amplitude. However, the lift force acting on the cylinder cannot be estimated in the same manner. In fact, both the lift force amplitude and frequency are modulated. The suggested expression provides a better approximation of the lift force. Moreover, it reveals that the presence of the higher harmonics in the lift force is the result of the amplitude and frequency modulation. (paper)

Gating system optimization of low pressure casting A356 aluminum alloy intake manifold based on numerical simulation

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Jiang Wenming

2014-03-01

Full Text Available To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on filling and solidification processes of the casting was carried out using the ProCAST software. The gating system of the casting is optimized according to the simulation results. Results show that when the gating system consists of only one sprue, the filling of the molten metal is not stable; and the casting does not follow the sequence solidification, and many shrinkage porosities are observed through the casting. After the gating system is improved by adding one runner and two in-gates, the filling time is prolonged from 4.0 s to 4.5 s, the filling of molten metal becomes stable, but this casting does not follow the sequence solidification either. Some shrinkage porosity is also observed in the hot spots of the casting. When the gating system was further improved by adding risers and chill to the hot spots of the casting, the shrinkage porosity defects were eliminated completely. Finally, by using the optimized gating system the A356 aluminum alloy intake manifold casting with integrated shape and smooth surface as well as dense microstructure was successfully produced.

Vivência integrada na comunidade: inserção longitudinal no Sistema de Saúde como estratégia de formação médica

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Ana Luiza de Oliveira e Oliveira

Full Text Available Propostas inovadoras para o processo ensino-aprendizagem nos cursos de Medicina vêm sendo desenvolvidas em busca de uma formação profissional generalista, humanista e crítica. A partir da aprovação do Programa Mais Médicos (PMM, novas escolas foram criadas adotando metodologias de ensino ativas e promovendo maior integração ensinoserviço-comunidade. Este artigo é um relato de experiência sobre o desenvolvimento do módulo Vivência Integrada na Comunidade no curso de Medicina da Escola Multicampi de Ciências Médicas do Rio Grande do Norte, que oportuniza ao estudante uma inserção longitudinal no sistema de Saúde em municípios do interior do Nordeste. Essa proposta vem promovendo maior integração entre a universidade, os gestores e os trabalhadores da Saúde. A aposta é a de que este módulo poderá contribuir com a fixação do médico na região e fortalecer o sistema de Saúde no interior do Brasil.

Vivências de idosos submetidos à prostatectomia por câncer: subsídios para o cuidado de enfermagem = Experiences of elderly people subjected to prostatectomy for cancer: subsidies for the care of nursing

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Stumm, Eniva Miladi Fernandes et al.

2010-01-01

Full Text Available O câncer de próstata é o mais incidente na terceira idade. A pesquisa busca apreender vivências de idosos submetidos à prostatectomia por câncer e mecanismos de enfrentamento utilizados para lidar com a situação. É qualitativa, descritiva, com 14 idosos residentes no município de Três Passos – RS. Os instrumentos de coleta de dados foram as observações em diário de campo e a entrevista semiestruturada. Da análise do conteúdo imerso nas falas dos idosos, emergiu uma categoria analítica – o idoso vivenciando e enfrentando o processo de adoecimento por câncer de próstata, subdividida em quatro temas: o conhecimento do diagnóstico de câncer; a aceitação das modalidades de tratamento propostas; a vivência de complicações cirúrgicas e da radioterapia; as estratégias utilizadas pelos idosos para lidar com o câncer. Os resultados desta pesquisa podem contribuir com profissionais, pesquisadores, estudantes da área da saúde, no sentido de refletir e de qualificar a assistência ao idoso com câncer de próstata. Prostate cancer is most incident in the third age. The research searches to learn through the experience of people subjected to prostatectomy due to cancer and mechanisms to deal with the situation. Descriptive is qualitatively, with 14 elderly resident in the city of Três Passos/RS. The data collection instruments were field journaling observation and semi structured interview. Through the analysis of the content immersed in the interview of the elderly emerged an analytical category: The elderly experiencing and addressing the process of getting sick by prostate cancer, subdivided into four themes: knowledge of cancer diagnosis; the acceptance of the proposed treatment modalities; surgical experience complications and radiotherapy. The strategies used by elderly for dealing with cancer. The results of this research can contribute with professionals, researchers, healthcare students in order to reflect and

Polynomial reconstruction of radial catalyst concentration distribution in an experimental type FCC riser for a low number of transversal projections in gamma ray tomography

International Nuclear Information System (INIS)

Melo, Silvio B.; Simoes, Francisco P.M.; Oliveira, Eric F. de; Santos, Maria das Gracas dos; Dantas, Carlos C.

2007-01-01

In the FCC - Fluid Catalytic Cracking process the Riser is an opaque cylinder, so that, in order to investigate the catalyst concentration inside, a gamma- ray based tomography is employed. Each section is submitted to a parallel beam and by means of the Beer-Lambert transmission is calculated. This tomography session is repeated from different angles, in manual tomographic experiments where the source/detector pair is rotated, producing in each direction what we called a transversal projection. In order to reconstruct the concentration of the present catalyst in a given moment some methods use successfully the inverse Radon transform through the filtered back-projection algorithm. The results are fully satisfactory for a large number of projections, widely seen as better than those produced by the algebraic methods. For a low number of projections, however, the algebraic methods become more competitive. In practice, simple experimental set-ups work with less than 10 projections, due to the time taken by the whole process. In this work, we present an investigation of polynomial reconstructions by using Bezier surfaces of arbitrary degree, adjusted to the experimental data through a least squares method. A computational algorithm was developed to implement the mathematical reconstruction for the 3D graphics presentation. (author)

Subsea technology 2004

International Nuclear Information System (INIS)

2004-10-01

The conference focuses on Subsea problems and requirements and contains 18 presentation on the topics: Flow management, autonomous underwater vehicles, risers and other technologies, installation of offshore production and exploitation units, management and maintenance of Subsea installations, design, production and functionality aspects of the Subsea structures and equipment, simulation aspects and oil and gas exploitation and production. (tk)

Transport of iron particles generated during milling operations in multilateral wells; Transporte de particulas de aco geradas pela abertura de janelas em pocos multilaterais

Energy Technology Data Exchange (ETDEWEB)

Martins, Andre Leibsohn; Rezende, Carla Leonor Teixeira; Leal, Rafael Amorim Ferreira; Lourenco, Fabio Gustavo Fernandes [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas]. E-mail: aleibsohn@cenpes.petrobras.com.br; rezenc@hotmail.com; ramorim@cenpes.petrobras.com.br; fabiolou@urbi.com.br

2000-07-01

This paper presents a series of numerical simulations aimng the definition of requirements (flow rate and fluid properties) to remove iron particles both in the inclined sections and in the riser annulus. Additionally, experimental work was developed in a pilot scale flow loop in order tocompare the behavior of water and sinthetic oil baed fluids in milling operations. (author)

Subsea technology 2004

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

The conference focuses on Subsea problems and requirements and contains 18 presentation on the topics: Flow management, autonomous underwater vehicles, risers and other technologies, installation of offshore production and exploitation units, management and maintenance of Subsea installations, design, production and functionality aspects of the Subsea structures and equipment, simulation aspects and oil and gas exploitation and production. (tk)

Vivências no espaço escolar: uma entrevista com Jaqueline Pasuch

Directory of Open Access Journals (Sweden)

Ana Paula Néia

2013-07-01

Full Text Available O Curso de Licenciatura Plena em Pedagogia prioriza a relação e as vivências entre o acadêmico e o espaço educativo/escola infantil, e o processo de humanização entre troca de saberes acontece na socialização de conhecimentos através dos estágios em que as bases teóricas apreendidas são aplicadas oportunizando a formação docente. A professora Jaqueline Pasuch nos dedicou seu tempo e sua contribuição foi significativa para nós acadêmicos do 7º semestre por entendemos que o professor para atuar na Educação Infantil deve entender que o educar e o cuidar acontecem de forma simultânea. Cabe ao professor assumir uma postura adequada às necessidades da criança pequena, reconhecendo seus direitos e proporcionando situações em um ambiente aconchegante e interessante. Envolver as crianças com contos de fadas permitem a exploração do imaginário infantil e o papel do professor de educação infantil, neste sentido, é apresentar desde bebês de zero até cinco/seis anos os primeiros contatos com o universo do letramento. A criança vai interagir com as histórias e o professor vai se tornado um contador de história, na interação as crianças podem ser os autores de textos criados no coletivo da turma, construindo saberes. A troca de experiências entre as crianças se torna significativa na medida em que elas constroem uma relação afetiva com a escola com o professor e com as famílias. O apoio familiar na Educação Infantil é um estímulo para o desenvolvimento da criança. A instituição deve se organizar para receber as famílias. Nestas perspectivas de contribuir com os saberes na Educação Infantil, que corresponde à primeira etapa da educação básica, entrevistamos a professora Jaqueline Pasuch, que tem experiência na área de Educação com ênfase em Políticas Públicas Educacionais, atuando principalmente nos seguintes temas: educação infantil, infância, escola, sociedade contemporânea, fam

IODP Expedition 338: Riser and Riserless Drilling Along the NanTroSEIZE Transect

Science.gov (United States)

Strasser, M.; Moore, G. F.; Dugan, B.; Kanagawa, K.; Toczko, S.

2013-12-01

Integrated Ocean Drilling Program (IODP) Expedition 338 provided new constraints on the Kumano Basin sediments, the accretionary prism inner wedge, the seaward extension of the megasplay fault, the architecture and mechanics of landslides, and the alteration of oceanic basement of the incoming Philippine Sea plate. This was accomplished through riser and riserless drilling, logging while drilling (LWD), and cuttings and core analysis. Cuttings and LWD analyses at Hole C0002F reveal two lithologic units in the prism inner wedge which are separated by a prominent fault zone at ~1640 mbsf. Mud-gases from the inner prism show high concentrations at the top of the wedge that decrease, but become more thermogenic, with depth. These data are from the previously unaccessed deeper part of the Nankai accretionary prism. Riserless coring at Site C0002 provided data across the gas hydrate zone of the Kumano Basin, across the Kumano Basin-accretionary prism unconformity, and in the uppermost accretionary prism. Within the Kumano basin section, gas and porewater geochemistry documents microbial methane gas in hydrates that are disseminated in sandy layers. Multiple penetrations of the Kumano Basin-accretionary prism boundary and 3D seismic data show that the boundary is erosive and complex. LWD (Site C0018) and coring and LWD (Site C0021) augment existing data to better understand submarine landslide dynamics and mass-transport deposit (MTD) emplacement processes. Previous coring at Site C0018 identified six MTDs, but only two MTD intervals were detected in resistivity images that show high angle, randomly oriented bedding. Site C0021, located more proximal to the MTD source, provides constraint on MTD variability. Correlation across the sites reveals a thick MTD with an erosional base characterized by a shear zone in muddy sediments vs. a translational basal surface within coarse volcaniclastic sand in the proximal and distal/lateral areas, respectively. LWD data and cores from

Simultaneous solution algorithms for Eulerian-Eulerian gas-solid flow models: Stability analysis and convergence behaviour of a point and a plane solver

International Nuclear Information System (INIS)

Wilde, Juray de; Vierendeels, Jan; Heynderickx, Geraldine J.; Marin, Guy B.

2005-01-01

Simultaneous solution algorithms for Eulerian-Eulerian gas-solid flow models are presented and their stability analyzed. The integration algorithms are based on dual-time stepping with fourth-order Runge-Kutta in pseudo-time. The domain is solved point or plane wise. The discretization of the inviscid terms is based on a low-Mach limit of the multi-phase preconditioned advection upstream splitting method (MP-AUSMP). The numerical stability of the simultaneous solution algorithms is analyzed in 2D with the Fourier method. Stability results are compared with the convergence behaviour of 3D riser simulations. The impact of the grid aspect ratio, preconditioning, artificial dissipation, and the treatment of the source terms is investigated. A particular advantage of the simultaneous solution algorithms is that they allow a fully implicit treatment of the source terms which are of crucial importance for the Eulerian-Eulerian gas-solid flow models and their solution. The numerical stability of the optimal simultaneous solution algorithm is analyzed for different solids volume fractions and gas-solid slip velocities. Furthermore, the effect of the grid resolution on the convergence behaviour and the simulation results is investigated. Finally, simulations of the bottom zone of a pilot-scale riser with a side solids inlet are experimentally validated

Casting of Hearth Plates from High-chromium Steel

Directory of Open Access Journals (Sweden)

Drotlew A.

2014-12-01

Full Text Available The paper presents the results of studies on the development of manufacturing technologies to cast hearth plates operating in chamber furnaces for heat treatment. Castings made from the heat-resistant G-X40CrNiSi27-4 steel were poured in hand-made green sand molds. The following operations were performed: computer simulation to predict the distribution of internal defects in castings produced by the above mentioned technology with risers bare and coated with exothermic and insulating sleeves, analysis of each variant of the technology, and manufacture of experimental castings. As a result of the conducted studies and analysis it was found that the use of risers with exothermic sleeves does not affect to a significant degree the quality of the produced castings of hearth plates, but it significantly improves the metal yield.

Perfil sociodemográfico e de experiências anômalas em indivíduos com vivências psicóticas e dissociativas em grupos religiosos Sociodemographic and anomalous experiences profile in subjects with psychotic and dissociative experiences in religious groups

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Adair Menezes Jr.

2012-01-01

Full Text Available CONTEXTO: Vivências psicóticas e dissociativas não patológicas são comuns na população geral, especialmente em grupos religiosos. Há poucos estudos sobre o perfil da população não clínica com essas vivências, bem como há dúvidas sobre critérios para o diagnóstico diferencial dessas experiências. OBJETIVOS: Identificar o perfil sociodemográfico e de experiências anômalas (EA entre pessoas que buscaram ajuda em centros espíritas. MÉTODOS: Foram entrevistadas 115 pessoas que procuraram auxílio em seis centros espíritas de Juiz de Fora/MG por causa de vivências psicóticas e/ou dissociativas. Entrevista semiestruturada investigou dados sociodemográficos, experiências anômalas apresentadas e a presença de critérios propostos para identificar experiências espirituais não patológicas. RESULTADOS: Predomínio de mulheres (70%, de meia-idade, com alta escolaridade, ativas ocupacionalmente e cujas EA começaram na infância (65% ou adolescência (23%. As EA mais frequentes foram alucinações visuais (63%, auditivas (54%, "percepção espiritual" (53%, "sonhos paranormais" (38% e experiências fora do corpo (31%. Para a maioria da amostra, essas EA não traziam prejuízos sócio-ocupacionais, eram curtas, episódicas e benéficas; entretanto referiram sofrimento emocional e falta de controle sobre elas. CONCLUSÃO: A alta frequência e diversidade de EA encontradas, bem como suas implicações teóricas, clínicas e de saúde pública, indicam a urgência de maior atenção a esse tópico.BACKGROUND: Non-pathological psychotic and dissociative experiences are frequent in the general population, particularly in religious groups. There are few studies on the profile of non-clinical populations with these experiences, and on criteria for differential diagnosis. OBJECTIVES: To identify the sociodemographic profile and anomalous experiences (AE among people who sought help in spiritualist groups. METHODS: We interviewed 115

Mulheres idosas: desvelando suas vivências e necessidades de cuidado Mujeres ancianas: revelando sus experiencias y necesidades de cuidado Elderly women: revealing their experiences and care needs

Directory of Open Access Journals (Sweden)

Miriam Aparecida Barbosa Merighi

2013-04-01

Full Text Available Estudo qualitativo com abordagem da fenomenologia social que objetivou a compreensão da vivência da mulher idosa, suas necessidades de cuidado e expectativas nesse período da vida. Participaram nove mulheres, cujos depoimentos foram obtidos de fevereiro a maio de 2011, por meio de entrevista semiestruturada. A mulher idosa refere limitações de ordem física, mental e social, e valoriza a preservação de sua autonomia nas atividades diárias e no cuidado consigo mesma. Refere a família como suporte fundamental e tem expectativas e necessidades de se manter saudável, da busca pelo lazer e de ter melhor acesso aos serviços de saúde para receber informações e atendimento qualificado. Nessa fase, a ausência de perspectivas relaciona-se à perda de pessoas significativas e da saúde. Este estudo revelou facetas da vivência da mulher idosa, suscitando novas investigações e a adequação do ensino, prática e gestão às reais necessidades dessa mulher.Estudio cualitativo con abordaje de fenomenología social, objetivando comprender la experiencia de la mujer anciana, sus necesidades de cuidado y expectativas en dicho período. Participaron nueve mujeres, cuyos testimonios fueron obtenidos de febrero a mayo de 2011 mediante entrevista semiestructurada. La mujer anciana refiere limitaciones de orden físico, mental y social, y valoriza la preservación de su autonomía en las actividades diarias en el cuidado de sí misma. Determina a la familia como soporte fundamental, tiene expectativas y necesidades de mantenerse saludable, adhiere a actividades recreativas y busca mejor acceso a servicios de salud, para recibir información y atención calificada. En esta fase, la ausencia de perspectivas se relaciona a la perdida de personas cercanas y de la salud. El estudio reveló facetas de la experiencia de la mujer anciana, sugiriendo nuevas investigaciones y la adecuación de la enseñanza, práctica y gestión a las reales necesidades de

Investigation of the motion processes of wastewater in sewerage of high-rise buildings

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Pomogaeva Valentina

2018-01-01

Full Text Available When designing, constructing and operating sewage pipelines in high-rise buildings, issues of failure-free operation of a network arise. Investigation of the processes of wastewater moving allows identifying problem areas during operation, assessing the possibility of obstructions and breakdowns of plumbing traps on the gravity drainage sections of the pipeline. The article performs the schemes of the water outflow from the floor sewer into the riser, including the places where the riser is bent, of air delivery to the working riser under the change of the direction of drain movement with the dropout line set-up, with the installation of an automatic anti-vacuum valve, with the installation of the ventilation pipeline. Investigations of the process of sewage waste flow in a sewage riser were carried out, in order to select the appropriate structure. The authors consider structure features of some sections of sewerage in high-rise buildings. The exhaustion value in the riser is determined from the rarefactions that occur below the compressed cross-section of the riser and the loss of the air flow pressure coming from the atmosphere into the riser during the deflooding of the liquid. Preventing the formation of obstructions and breakdowns of plumbing traps is an integral part of sewage networks.

Investigation of the motion processes of wastewater in sewerage of high-rise buildings

Science.gov (United States)

Pomogaeva, Valentina; Metechko, Lyudmila; Prokofiev, Dmitry; Narezhnaya, Tamara

2018-03-01

When designing, constructing and operating sewage pipelines in high-rise buildings, issues of failure-free operation of a network arise. Investigation of the processes of wastewater moving allows identifying problem areas during operation, assessing the possibility of obstructions and breakdowns of plumbing traps on the gravity drainage sections of the pipeline. The article performs the schemes of the water outflow from the floor sewer into the riser, including the places where the riser is bent, of air delivery to the working riser under the change of the direction of drain movement with the dropout line set-up, with the installation of an automatic anti-vacuum valve, with the installation of the ventilation pipeline. Investigations of the process of sewage waste flow in a sewage riser were carried out, in order to select the appropriate structure. The authors consider structure features of some sections of sewerage in high-rise buildings. The exhaustion value in the riser is determined from the rarefactions that occur below the compressed cross-section of the riser and the loss of the air flow pressure coming from the atmosphere into the riser during the deflooding of the liquid. Preventing the formation of obstructions and breakdowns of plumbing traps is an integral part of sewage networks.

FY 1990 report on the results of the R and D of the manganese nodule mining system. 4/6 volume. Nodule rising system; 1990 nendo mangan dankai saiko system no kenkyu kaihatsu seika hokokusho. 4/6. Yoko system hen

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-03-01

The paper aims at conducting the R and D of a system to mine manganese nodule at the bottom of deep sea by the fluid dredging system. For it, a mining/experimental system was developed and trially fabricated for the overall ocean experiment. Functions of the system were confirmed, and various data were collected on the design for development of practical use system. In the R and D in this fiscal year, the following were conducted: 1) detailed design of equipment for the overall ocean experiment, and fabrication of a part of the equipment. 2) making of procedures for the experiment conducted under the overall ocean experimental plan, survey of the sea area for experiment, etc. 3) overall experimental simulation of strength of nodule riser, etc. which was considered of a behavior of nodule collector and safety of nodule riser at the time of handling/mining. 4) study of the basic plan on a mining system. As to the nodule riser, the detailed design was proceeded with of the strength at the time of handling by the fixed derrick, and a design draft needed for fabrication of the actual one was worked out. Relating to the flexible hose, the design strength of the whole hose was confirmed. Further, out of the flexible hoses, a part of the tensile load resistant hoses was fabricated as materials for the overall ocean experiment. Concerning the vibration isolator, a draft on the display was drawn up, and the detailed design was also made of the winding device to put the helical wire on to the nodule riser. (NEDO)

Seabrook simulator model upgrade: Implementation and validation of two-phase, nonequilibrium RCS and steam generator models

International Nuclear Information System (INIS)

Kao, S.

1990-01-01

A number of deficiencies in the original RCS and steam generator models on the Seabrook simulator were found to give unrealistic results under some off-normal and accident conditions. These deficiencies are attributed to the simplistic assumptions used in the original models, such as the homogeneous, equilibrium equations used in the pressurizer and steam generator models, and the single-phase flow model used in the RCS thermal-hydraulic model. To improve the fidelity of the simulator, efforts have been made to upgrade the RCS and steam generator models to include two-phase, nonequilibrium features. In the new RCS model, the following major assumptions are used to derive the finite difference form of the conservation equations: a donor-cell differencing scheme is adopted to allow flow reversal; a single pressure is used to evaluate properties; a single mass flow rate is assumed in each loop; enthalpy is assumed to vary linearly within each control volume; a homogeneous flow is assumed under two-phase conditions. The pressurizer is divided into a vapor region and a liquid region, each of which is represented by a set of mass and energy conservation equations. Interfacial mass and energy exchange mechanisms (condensation and flashing), thermal interactions between the vessel and fluids, and thermal nonequilibrium between the phases are included in the pressurizer model. The steam generator is divided into the vapor dome, riser, and downcomer regions. The assumptions applied are similar to those of the RCS and pressurizer models. A momentum model is incorporated to calculate the recirculation flow and simulate the downcomer level shrink/swell phenomenon. The new RCS and steam generator models are validated by comparing the simulator calculations against sister plant data and FSAR vendor analysis. The results show the new models give realistic and reliable calculations under off-normal and accident conditions

Principal component analysis in an experimental cold flow model of a fluid catalytic cracking unit by gammametry

International Nuclear Information System (INIS)

Araujo, Janeo Severino C. de; Dantas, Carlos Costa; Santos, Valdemir A. dos; Souza, Jose Edson G. de; Luna-Finkler, Christine L.

2009-01-01

The fluid dynamic behavior of riser of a cold flow model of a Fluid Catalytic Cracking Unit (FCCU) was investigated. The experimental data were obtained by the nuclear technique of gamma transmission. A gamma source was placed diametrically opposite to a detector in any straight section of the riser. The gas-solid flow through riser was monitored with a source of Americium-241 what allowed obtaining information of the axial solid concentration without flow disturbance and also identifying the dependence of this concentration profile with several independent variables. The MatLab R and Statistica R software were used. Statistica tool employed was the Principal Components Analysis (PCA), that consisted of the job of the data organization, through two-dimensional head offices to allow extract relevant information about the importance of the independent variables on axial solid concentration in a cold flow riser. The variables investigated were mass flow rate of solid, mass flow rate of gas, pressure in the riser base and the relative height in the riser. The first two components reached about 98 % of accumulated percentage of explained variance. (author)

Oil production system

Energy Technology Data Exchange (ETDEWEB)

Ballantyne, J F

1983-12-21

A new oil producing system is proposed which consists of a group of underwater wells, an underwater riser and a floating storage facility for the production of the wells. The group of wells and the riser are interconnected through a manifold system in such a way that the production from any well or from the entire group of wells go to the base (foundation) of the riser. From above the riser is connected with the floating storage facility which is equipped, besides tanks for storing the well products, with a separation device for separating the oil and the accompanying gas. The gas is used as a fuel for producing electric power required by the dynamic positioning systems. The products from each well are tested by means of a regulable coupling controlled by means of a cable, which is passed from the surface through the riser. The wellhead equipment for the unslanted wells is mounted on a template previously installed on the sea floor. From the template the well products enter the riser through the manifold unit system.

Feasibility of Valve-in-Valve Procedure for Degenerated St. Jude Medical Trifecta Bioprosthesis.

Science.gov (United States)

Verhoye, Jean-philippe; Harmouche, Majid; Soulami, Reda Belhaj; Thebault, Christophe; Boulmier, Dominique; Leguerrier, Alain; Anselmi, Amedeo

2015-07-01

The valve-in-valve (ViV) procedure is an option for patients with symptomatic structural degeneration of a bioprosthesis and excessive reoperative risk. The risk of coronary obstruction appears to be increased if ViV is performed for certain pericardial prostheses in which the leaflets are mounted outside the stent posts. Herein is described a successful ViV for a degenerated Trifecta aortic bioprosthesis, and the technical considerations for performing a ViV procedure within such types of prosthesis are considered. Emphasis is placed on the importance of preoperative investigations (computed tomography scan-based measurements of coronary ostial height and of sinus of Valsalva diameters), and on the precise deployment of the valve (transapical approach with transesophageal echocardiography control) to minimize the risk of major complications. The presence of a failing Trifecta bioprosthesis should not be considered an absolute contraindication to ViV on the basis of the risk of coronary obstruction.

Technologie pour le forage scientifique en eau très profonde au XXIe siècle Deepwater Technology for Scientific Drilling in the 21st Century

Directory of Open Access Journals (Sweden)

Sparks C.

2006-11-01

Full Text Available Le présent article aborde les slimline risers et les systèmes de forage minier qui sont deux domaines technologiques dont le potentiel doit permettre d'améliorer le forage et le carottage scientifiques en eau très profonde au cours du XXIe siècle. Cet article présente les avantages et les inconvénients des slimline risers, par rapport aux risers de forage utilisés par l'industrie pétrolière. Le potentiel de matériaux nouveaux est évoqué. Des analyses préliminaires de slimline risers fabriqués de différents matériaux (acier, titane, aluminium et composite pour forage scientifique par 4 000 m de profondeur d'eau sont présentées. La seconde partie de l'article aborde les moyens d'adapter les systèmes de forage minier aux grands fonds. This paper addresses slimline riser systems and mining drilling systems which are two items of technology that have the potential to improve scientific drilling and coring in deep water in the 21st century. The paper presents the advantages and disadvantages of drilling with a slimline riser, compared to an oil industry riser. The potential of new materials are discussed. Preliminary analyses of slimline risers made from different materials (steel, titanium, aluminium and composite for 4000 m of water are presented. In the second part of the paper, ways of adapting mining systems to deepwater are discussed.

VIH no feminino: vivência psicológica VIH en el feminino: vivencia psicológica HIV and the female gender: the psychological experience

Directory of Open Access Journals (Sweden)

Sílvia do Rosário Piteira Natário de Lourenço

2009-02-01

Full Text Available A SIDA coloca questões sociais, humanitárias e jurídicas cruciais, e ameaça alterar seriamente fundamentos da estrutura social de tolerância e entendimento que sustém a vida das nossas sociedades. A partir de uma contextualização dos aspectos clínicos e epidemiológicos do VIH/SIDA, este artigo de revisão bibliográfica faz uma abordagem da vivência psicológica e das implicações da infecção com o Vírus da Imunodeficiência Humana Adquirida na mulher grávida.SIDA plantea cuestiones sociales, humanitarias y jurídicas fundamentales, y amenaza cambiar gravemente motivos de la estructura social de tolerancia y comprensión, que sustenta la vida de nuestra sociedad. Desde una contextualización de los aspectos clínico y epidemiológicos del VIH / SIDA, en este artículo de revisión bibliográfica se hace un enfoque acerca de la v psicológica y la implicación de la infección por el Virus de Inmunodeficiencia Humana Adquirida en la mujer embarazada.AIDS raises a social issue, humanitarian, legal, and threatens to change the social structure founding of tolerance and understanding, that sustains the life of our societies. From a clinical and epidemiological background of HIV/AIDS, this article of literature review makes an approach about psychological experience and implication of the Human Immunodeficiency Virus infection in pregnant woman.

Essential oil composition and biological activity from Artemisia caerulescens subsp. densiflora (Viv.) Gamisans ex Kerguélen & Lambinon (Asteraceae), an endemic species in the habitat of La Maddalena Archipelago.

Science.gov (United States)

Ornano, Luigi; Venditti, Alessandro; Ballero, Mauro; Sanna, Cinzia; Donno, Yuri; Quassinti, Luana; Bramucci, Massimo; Vitali, Luca A; Petrelli, Dezemona; Tirillini, Bruno; Papa, Fabrizio; Maggi, Filippo; Bianco, Armanodoriano

2016-08-01

The purpose of this study was to investigate the composition of the essential oil obtained from a population of Artemisia caerulescens subsp. densiflora growing in Razzoli, an island in the La Maddalena Archipelago (Sardinia, Italy). A. caerulescens sups. densiflora Viv. (Asteraceae), a wild herb, seldom studied in the Mediterranean, represents one of the many rare endemic species growing in North Sardinia. The essential oil composition was analysed by means of GC/MS analysis, which showed davana ethers as the major volatile components, accounting together for 17.5%, followed by (E)-nerolidol (4.5%), β-oplopenone (3.3%), cis-sabinene hydrate (5.2%) and terpinen-4-ol (4.7%). The oil was tested for antioxidant activity by means of DPPH test, inhibition of lipid oxidation test and hypochlorous acid test, which showed a quite interesting scavenger capacity. For the first time, we reported the cytotoxic activity of the essential oil of A. caerulescens subsp. densiflora, against three human tumour cell lines (A375, MDA-MB231 and HCT116), with IC50 values in the range 5.20-7.61 μg/mL, which deserved further studies to support its use as chemopreventive agent. Finally, the antimicrobial activity of the essential oil, displayed on a panel of human pathogens, was very low.

Dynamic Responses of Flexible Cylinders with Low Mass Ratio

Science.gov (United States)

Olaoye, Abiodun; Wang, Zhicheng; Triantafyllou, Michael

2017-11-01

Flexible cylinders with low mass ratios such as composite risers are attractive in the offshore industry because they require lower top tension and are less likely to buckle under self-weight compared to steel risers. However, their relatively low stiffness characteristics make them more vulnerable to vortex induced vibrations. Additionally, numerical investigation of the dynamic responses of such structures based on realistic conditions is limited by high Reynolds number, complex sheared flow profile, large aspect ratio and low mass ratio challenges. In the framework of Fourier spectral/hp element method, the current technique employs entropy-viscosity method (EVM) based large-eddy simulation approach for flow solver and fictitious added mass method for structure solver. The combination of both methods can handle fluid-structure interaction problems at high Reynolds number with low mass ratio. A validation of the numerical approach is provided by comparison with experiments.

SCALING SOLID RESUSPENSION AND SORPTION FOR THE SMALL COLUMN ION EXCHANGE PROCESSING TANK

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Qureshi, Z.

2010-12-14

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing 1.3 million gallon waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending and resuspending Monosodium Titanate (MST), Crystalline Silicotitanate (CST), and simulated sludge. In addition, SRNL will also be conducting pilot-scale tests to determine the mixing requirements for the strontium and actinide sorption. As part of this task, the results from the pilot-scale tests must be scaled up to a full-scale waste tank. This document describes the scaling approach. The pilot-scale tank is a 1/10.85 linear scale model of Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX Program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations). MST additions are through Riser E1, the proposed MST addition riser in Tank 41H. To determine the approach to scaling the results from the pilot-scale tank to Tank 41H, the authors took the following approach. They reviewed the technical literature for methods to scale mixing with jets and suspension of solid particles with jets, and the technical literature on mass transfer from a liquid to a solid particle to develop approaches to scaling the test data. SRNL assembled a team of internal experts to review the scaling approach and to identify alternative approaches that should be considered.

A Casting Yield Optimization Case Study: Forging Ram

DEFF Research Database (Denmark)

Kotas, Petr; Tutum, Cem Celal; Hattel, Jesper Henri

2010-01-01

This work summarizes the findings of multi-objective optimization of a gravity sand-cast steel part for which an increase of the casting yield via riser optimization was considered. This was accomplished by coupling a casting simulation software package with an optimization module. The benefits...... of this approach, recently adopted in foundry industry world wide and based on fully automated computer optimization, were demonstrated. First, analyses of filling and solidification of the original casting design were conducted in the standard simulation environment to determine potential flaws and inadequacies...

Synthesis, characterization, spectroscopic and catalytic oxidation studies of Fe(III), Ni(II), Co(III), V(IV) and U(VI) Schiff base complexes with N, O donor ligands derived from 2,3-diaminopyridine

Energy Technology Data Exchange (ETDEWEB)

Zabardasti, Abedien; Shangaie, Sayed Asad [Lorestan Univ., Khorramabad (Iran, Islamic Republic of). Dept. of Chemistry

2016-10-15

Fifteen new complexes of transition metals were designed using three Schiff base ligands and aldol condensation of 2,3-diaminopyridine with 5-R-2-hydroxybenzaldehyde (R = F, Cl, Br) in the 1:2 molar ratio. The tetradentate ligands N,N{sup '}-bis(5-R-2-hydroxybenzaldehyde) pyridine were acquired with the common formula H{sub 2}[(5-R-sal){sub 2}py] and characterized by IR, UV-Vis spectra, {sup 1}H-NMR and elemental analysis. These ligands produce 1:1 complexes M[(5-R-sal){sub 2}py] with Fe(III), Ni(II), Co(III), V(IV) and U(VI) metal ions. The electronic property and nature of complexes were identified by IR, UV-Vis spectra, elemental analysis, X-ray crystallography and cyclic voltammetric methods. The catalytic activity of complexes for epoxidation of styrene with UHP as primary oxidant at minimal temperature (10 C) has been planned. The spectral data of the ligands and their complexes are deliberate in connection with the structural changes which happen due to complex preparation. The electrochemical outcome has good conformability with what suggested for electronic interaction among metal center and ligand by the UV-Vis and IR measurements.

Redox Equilibria in SO2 Oxidation Catalysts

DEFF Research Database (Denmark)

Rasmussen, Søren Birk; Eriksen, Kim Michael; Boghosian, Soghomon

1999-01-01

been carried out regarding the complex and compound formation of V(V) and the formation of V(IV) and V(III) compounds with low solubility causing catalyst deactivation. However, the redox chemistry of vanadium and the complex formation of V(IV) is much less investigated and further information...... on these subjects in pyrosulfate melts is needed to obtain a deeper understanding of the reaction mechanism. The present paper describes our efforts so far to study the V(IV) chemistry using especially spectroscopic and electrochemical methods....

Percepção dos pais sobre a vivência no método mãe-canguru La percepción de los padres en la vivencia del método madre-canguro Perception of parents in experiencing the kangaroo mother method

Directory of Open Access Journals (Sweden)

Cláudia Elisângela Fernandes Bis Furlan

2003-08-01

Full Text Available O presente estudo tem como objetivo analisar a percepção de pais de bebês prematuros sobre a vivência no Método Mãe-Canguru. Trata-se de estudo descritivo, inserido na abordagem qualitativa. Os dados foram coletados a partir de entrevista semi-estruturada com 10 pais, realizada em até 60 dias após a alta do prematuro do Canguru, realizado em um hospital filantrópico do interior do Estado de São Paulo. A percepção dos pais sobre a vivência foi agrupada em quatro núcleos temáticos: flexibilizando a permanência materna no Método Mãe-Canguru; favorecendo a relação mãe-filho e família; completando o crescimento e desenvolvimento do prematuro e desenvolvimento de habilidades para o cuidado com o filho. Os dados obtidos fornecem subsídios para a organização da assistência no Método Mãe-Canguru, tanto sob a perspectiva institucional da equipe atuante como da relação com a clientela, possibilitando a compreensão das dificuldades e significados atribuídos à vivência e otimização do cuidado de enfermagem.El presente estudio tiene como objetivo analizar la percepción de los padres de bebes prematuros en la vivencia del método Madre-Canguro. Este es un estudio descriptivo, inserido en un abordaje cualitativo. Los datos fueron recolectados a partir de entrevistas semiestructuradas con 10 padres, realizadas en un plazo máximo de 60 días después de la alta del prematuro del Canguro realizado en un hospital filantrópico del interior del Estado de São Paulo. La percepción de los padres con respecto a la vivencia en el Método, fue comprendida en cuatro núcleos temáticos: flexibilizando la permanencia materna en el Método Madre-Canguro; favoreciendo la relación madre-hijo y familia; completando el crecimiento y desarrollo del prematuro y desarrollo de habilidades para el cuidado con el hijo. Los datos obtenidos ofrecen aportes para la organización de la atención en el método Madre-Canguro, tanto en la perspectiva

Bioprosthetic Valve Fracture Improves the Hemodynamic Results of Valve-in-Valve Transcatheter Aortic Valve Replacement.

Science.gov (United States)

Chhatriwalla, Adnan K; Allen, Keith B; Saxon, John T; Cohen, David J; Aggarwal, Sanjeev; Hart, Anthony J; Baron, Suzanne J; Dvir, Danny; Borkon, A Michael

2017-07-01

Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) may be less effective in small surgical valves because of patient/prosthesis mismatch. Bioprosthetic valve fracture (BVF) using a high-pressure balloon can be performed to facilitate VIV TAVR. We report data from 20 consecutive clinical cases in which BVF was successfully performed before or after VIV TAVR by inflation of a high-pressure balloon positioned across the valve ring during rapid ventricular pacing. Hemodynamic measurements and calculation of the valve effective orifice area were performed at baseline, immediately after VIV TAVR, and after BVF. BVF was successfully performed in 20 patients undergoing VIV TAVR with balloon-expandable (n=8) or self-expanding (n=12) transcatheter valves in Mitroflow, Carpentier-Edwards Perimount, Magna and Magna Ease, Biocor Epic and Biocor Epic Supra, and Mosaic surgical valves. Successful fracture was noted fluoroscopically when the waist of the balloon released and by a sudden drop in inflation pressure, often accompanied by an audible snap. BVF resulted in a reduction in the mean transvalvular gradient (from 20.5±7.4 to 6.7±3.7 mm Hg, P valve effective orifice area (from 1.0±0.4 to 1.8±0.6 cm 2 , P valves to facilitate VIV TAVR with either balloon-expandable or self-expanding transcatheter valves and results in reduced residual transvalvular gradients and increased valve effective orifice area. © 2017 American Heart Association, Inc.

Bioprosthetic Valve Fracture During Valve-in-valve TAVR: Bench to Bedside.

Science.gov (United States)

Saxon, John T; Allen, Keith B; Cohen, David J; Chhatriwalla, Adnan K

2018-01-01

Valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR) has been established as a safe and effective means of treating failed surgical bioprosthetic valves (BPVs) in patients at high risk for complications related to reoperation. Patients who undergo VIV TAVR are at risk of patient-prosthesis mismatch, as the transcatheter heart valve (THV) is implanted within the ring of the existing BPV, limiting full expansion and reducing the maximum achievable effective orifice area of the THV. Importantly, patient-prosthesis mismatch and high residual transvalvular gradients are associated with reduced survival following VIV TAVR. Bioprosthetic valve fracture (BVF) is as a novel technique to address this problem. During BPV, a non-compliant valvuloplasty balloon is positioned within the BPV frame, and a highpressure balloon inflation is performed to fracture the surgical sewing ring of the BPV. This allows for further expansion of the BPV as well as the implanted THV, thus increasing the maximum effective orifice area that can be achieved after VIV TAVR. This review focuses on the current evidence base for BVF to facilitate VIV TAVR, including initial bench testing, procedural technique, clinical experience and future directions.

Opiniões e vivências de adolescentes acerca dos direitos ao respeito e privacidade e à proteção contra a violência física no âmbito familiar

Directory of Open Access Journals (Sweden)

Ana Paula Lazzaretti de Souza

2014-08-01

Full Text Available O objetivo deste estudo foi investigar a opinião e a vivência de adolescentes acerca dos direitos ao respeito e privacidade, e à proteção contra a violência física no âmbito familiar. Participaram 50 adolescentes de 12 a 18 anos (M=14,46, SD=1,38 da Região Metropolitana de Porto Alegre. Foram utilizados o Inventário de Autorrelato sobre a Situação dos Direitos e o Questionário sobre Conhecimento em Direitos. Do total, 32,7% relataram violação do direito ao respeito e privacidade, e 50% à proteção contra violência física. Não houve diferença significativa entre o grupo que sofreu muitas violações de direitos e o que sofreu poucas em relação à opinião sobre estes direitos específicos, entretanto, o grupo que sofreu tais violações apoiou mais a garantia destes direitos. Estes resultados indicam a importância de espaços de participação e discussão acerca das concepções de adolescentes sobre seus direitos.

Recent Development of the Empirical Basis for Prediction of Vortex Induced Vibrations

Directory of Open Access Journals (Sweden)

Carl M. Larsen

2016-02-01

Full Text Available This paper describes the research activity related to VIV that has taken place at NTNU and MARINTEK in Trondheim during the last years. The overall aim of the work has been increased understanding of the VIV phenomenon and to improve the empirical basis for prediction of VIV. The work has included experiments with flexible beams in sheared and uniform flow and forced motions of short, rigid cylinders. Key results in terms of hydrodynamic coefficients and analysis procedures have been implemented in the computer program VIVANA, which has resulted in new analysis options and improved hydrodynamic coefficients. Some examples of results are presented, but the main focus of the paper is to give an overview of the work and point out how the new results can be used in order to improve VIV analyses.

A formação humana em contexto de violência: uma compreensão clínica a partir da Fenomenologia de Edith Stein

OpenAIRE

Suzana Filizola Brasiliense Carneiro

2016-01-01

Este estudo, baseado na Fenomenologia de Edith Stein, teve por objetivo compreender as vivências fundamentais de pessoas que vivem em um contexto marcado pela violência, bem como investigar as repercussões dessas vivências em seu processo formativo. A pesquisa foi realizada no bairro do Uruguai, em Salvador (BA), região conhecida como Alagados. A apreensão das vivências ocorreu pelos registros de um diário de bordo e por 15 entrevistas abertas com os moradores. A análise foi realizada em dois...

A vivência de mulheres no parto domiciliar e hospitalar La vivencia de mujeres en el parto domiciliar y hospitalario Women experience with home and hospital childbirth

Directory of Open Access Journals (Sweden)

Cilene Delgado Crizóstomo

2007-03-01

Full Text Available Estudo com abordagem qualitativa, objetivando compreender na vivência das mulheres a experiência do parto normal domiciliar e hospitalar bem como discutir a vivência das mulheres nos dois tipos de partos. Os sujeitos do estudo foram sete mulheres multíparas residentes em Batalha PI, e o instrumento utilizado foi um roteiro semi-estruturado com a técnica da entrevista. Os resultados revelaram que os partos domiciliares vivenciados pelas mulheres aconteceram mais rápido, de forma natural, sem intervenções e assistidos por parteiras ou por suas mães. As posições de preferência durante o parto domiciliar foram na rede e no assento, e os partos hospitalares foram laboriosos, complicados e com intervenções traumáticas. A melhor posição e o melhor local do parto escolhidos pelas entrevistadas foram na rede e o domicílio, respectivamente. Conclui-se que o parto domiciliar foi natural e humanizado, já o parto normal hospitalar foi conduzido pelos profissionais com intervenções sem a participação ativa das parturientes, tornando-o traumático, desumano e de risco.Estudio con abordaje cualitativo, objetivando entender la experiencia de mujeres en parto natural en el domicilio y en el hospital, en cuanto se discute la experiencia de las mujeres en ambos tipos de parto. Los sujetos del estudio fueron siete mujeres multiparas que viven en Batalha - Piauí - Brasil, y los instrumentos usados fueran un guión semi-estructurado con la técnica de la entrevista. Los resultados revelaron que los partos en el domicilio experimentados por las mujeres sucedieron más rápidamente, de una manera natural, sin intervenciones y asistido por parteras o por sus madres. Las posiciones preferidas durante el parto en el domicilio fueron en la red y en el asiento, y los partos en el hospital fueran laboriosos, complicados y con intervenciones traumáticas. La mejor posición y la mejor localización del parto, escogidos por las entrevistadas, fueron la

Computational fluid dynamics (CFD) analysis of airlift bioreactor: effect of draft tube configurations on hydrodynamics, cell suspension, and shear rate.

Science.gov (United States)

Pawar, Sanjay B

2018-01-01

The biomass productivity of microalgae cells mainly depends on the hydrodynamics of airlift bioreactor (ABR). Thus, the hydrodynamics of concentric tube ABR was initially studied using two-phase three-dimensional CFD simulations with the Eulerian-Lagrangian approach. The performance of ABR (17 L) was examined for different configurations of the draft tube using various drag models such as Grace, Ishii-Zuber, and Schiller-Naumann. The gas holdups in the riser and the downcomer were well predicted using E-L approach. This work was further extended to study the dispersion of microalgae cells in the ABR using three-phase CFD simulations. In this model (combined E-E and E-L), the solid phase (microalgae cells) was dispersed into the continuous liquid phase (water), while the gas phase (air bubbles) was modeled as a particle transport fluid. The effect of non-drag forces such as virtual mass and lift forces was also considered. Flow regimes were explained on the basis of the relative gas holdup distribution in the riser and the downcomer. The microalgae cells were found in suspension for the superficial gas velocities of 0.02-0.04 m s -1 experiencing an average shear of 23.52-44.56 s -1 which is far below the critical limit of cell damage.

A detailed BWR recirculation loop model for RELAP

Energy Technology Data Exchange (ETDEWEB)

Araiza-Martínez, Enrique, E-mail: enrique.araiza@inin.gob.mx; Ortiz-Villafuerte, Javier, E-mail: javier.ortiz@inin.gob.mx; Castillo-Durán, Rogelio, E-mail: rogelio.castillo@inin.gob.mx

2017-01-15

Highlights: • A new detailed BWR recirculation loop model was developed for RELAP. • All jet pumps, risers, manifold, suction and control valves, and recirculation pump are modeled. • Model is tested against data from partial blockage of two jet pumps. • For practical applications, simulation results showed good agreement with available data. - Abstract: A new detailed geometric model of the whole recirculation loop of a BWR has been developed for the code RELAP. This detailed model includes the 10 jet pumps, 5 risers, manifold, suction and control valves, and the recirculation pump, per recirculation loop. The model is tested against data from an event of partial blockage at the entrance nozzle of one jet pump in both recirculation loops. For practical applications, simulation results showed good agreement with data. Then, values of parameters considered as figure of merit (reactor power, dome pressure, core flow, among others) for this event are compared against those from the common 1 jet pump per loop model. The results show that new detailed model led to a closer prediction of the reported power change. The detailed recirculation loop model can provide more reliable boundary condition data to a CFD models for studies of, for example, flow induced vibration, wear, and crack initiation.

Uncertainty evaluation by gamma transmission measurements and CFD model comparison in a FCC cold pilot unit

Directory of Open Access Journals (Sweden)

Dantas C.C.

2013-01-01

Full Text Available The solid flow in air-catalyst in circulating fluidized bed was simulated with CFD model to obtain axial and radial distribution. Therefore, project parameters were confirmed and steady state operation condition was improved. Solid holds up axial end radial profiles simulation and comparison with gamma transmission measurements are in a good agreement. The transmission signal from an 241Am radioactive source was evaluated in NaI(Tl detector coupled to multichannel analyzer. This non intrusive measuring set up is installed at riser of a cold pilot unit to determine parameters of FCC catalyst flow at several concentrations. Mass flow rate calculated by combining solid hold up and solid phase velocity measurements was compared with catalyst inlet measured at down-comer. Evaluation in each measured parameter shows that a relative combined uncertainty of 6% in a 95% interval was estimated. Uncertainty analysis took into account a significant correlation in scan riser transmission measurements. An Eulerian approach of CFD model incorporating the kinetic theory of granular flow was adopted to describe the gas–solid two-phase flows in a multizone circulating reactor. Instantaneous and local gas-particle velocity, void fraction and turbulent parameters were obtained and results are shown in 2 D and 3D graphics.

Uncertainty evaluation of fluid dynamic models and validation by gamma ray transmission measurements of the catalyst flow in a FCC cold pilot unity

International Nuclear Information System (INIS)

Teles, Francisco A.S.; Santos, Ebenezer F.; Dantas, Carlos C.; Melo, Silvio B.; Santos, Valdemir A. dos; Lima, Emerson A.O.

2013-01-01

In this paper, fluid dynamics of Fluid Catalytic Cracking (FCC) process is investigated by means of a Cold Flow Pilot Unit (CFPU) constructed in Plexiglas to visualize operational conditions. Axial and radial catalyst profiles were measured by gamma ray transmission in the riser of the CFPU. Standard uncertainty was evaluated in volumetric solid fraction measurements for several concentrations at a given point of axial profile. Monitoring of the pressure drop in riser shows a good agreement with measured standard uncertainty data. A further evaluation of the combined uncertainty was applied to volumetric solid fraction equation using gamma transmission data. Limit condition of catalyst concentration in riser was defined and simulation with random numbers provided by MATLAB software has tested uncertainty evaluation. The Guide to the expression of Uncertainty in Measurement (GUM) is based on the law of propagation of uncertainty and on the characterization of the quantities measured by means of either a Gaussian distribution or a t-distribution, which allows measurement uncertainty to be delimited by means of a confidence interval. A variety of supplements to GUM are being developed, which will progressively enter into effect. The first of these supplements [3] describes an alternative procedure for the calculation of uncertainties: the Monte Carlo Method (MCM).MCM is an alternative to GUM, since it performs a characterization of the quantities measured based on the random sampling of the probability distribution functions. This paper also explains the basic implementation of the MCM method in MATLAB. (author)

Uncertainty evaluation of fluid dynamic models and validation by gamma ray transmission measurements of the catalyst flow in a FCC cold pilot unity

Energy Technology Data Exchange (ETDEWEB)

Teles, Francisco A.S.; Santos, Ebenezer F.; Dantas, Carlos C., E-mail: francisco.teles@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Tecnologia e Geociencias. Departamento de Energia Nuclear; Melo, Silvio B., E-mail: sbm@cin.ufpe.br [Universidade Federal de Pernambuco (CIN/UFPE), Recife, PE (Brazil). Centro de Informatica; Santos, Valdemir A. dos, E-mail: vas@unicap.br [Universidade Catolica de Pernambuco (UNICAP), Recife, PE (Brazil). Dept. de Quimica; Lima, Emerson A.O., E-mail: emathematics@gmail.com [Universidade de Pernambuco (POLI/UPE), Recife, PE (Brazil). Escola Politecnica

2013-07-01

In this paper, fluid dynamics of Fluid Catalytic Cracking (FCC) process is investigated by means of a Cold Flow Pilot Unit (CFPU) constructed in Plexiglas to visualize operational conditions. Axial and radial catalyst profiles were measured by gamma ray transmission in the riser of the CFPU. Standard uncertainty was evaluated in volumetric solid fraction measurements for several concentrations at a given point of axial profile. Monitoring of the pressure drop in riser shows a good agreement with measured standard uncertainty data. A further evaluation of the combined uncertainty was applied to volumetric solid fraction equation using gamma transmission data. Limit condition of catalyst concentration in riser was defined and simulation with random numbers provided by MATLAB software has tested uncertainty evaluation. The Guide to the expression of Uncertainty in Measurement (GUM) is based on the law of propagation of uncertainty and on the characterization of the quantities measured by means of either a Gaussian distribution or a t-distribution, which allows measurement uncertainty to be delimited by means of a confidence interval. A variety of supplements to GUM are being developed, which will progressively enter into effect. The first of these supplements [3] describes an alternative procedure for the calculation of uncertainties: the Monte Carlo Method (MCM).MCM is an alternative to GUM, since it performs a characterization of the quantities measured based on the random sampling of the probability distribution functions. This paper also explains the basic implementation of the MCM method in MATLAB. (author)

PILOT-SCALE TESTING OF THE SUSPENSION OF MST, CST, AND SIMULATED SLUDGE SLURRIES IN A SLUDGE TANK

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Qureshi, Z.; Restivo, M.; Steeper, T.; Williams, M.; Herman, D.

2011-08-02

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Following strontium, actinide, and cesium removal, the concentrated solids will be transported to a sludge tank (i.e., monosodium titanate (MST)/sludge solids to Tank 42H or Tank 51H and crystalline silicotitanate (CST) to Tank 40H) for eventual transfer to the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for mixing MST, CST, and simulated sludge. The purpose of this pilot scale testing is to determine the pump requirements for mixing MST and CST with sludge in a sludge tank and to determine whether segregation of particles occurs during settling. Tank 40H and Tank 51H have four Quad Volute pumps; Tank 42H has four standard pumps. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 40H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 40H. The pump locations correspond to the current locations in Tank 40H (Risers B2, H, B6, and G). The pumps are pilot-scale Quad Volute pumps. Additional settling tests were conducted in a 30 foot tall, 4 inch inner diameter clear column to investigate segregation of MST, CST, and simulated sludge particles during settling.

Factors influencing left ventricular outflow tract obstruction following a mitral valve-in-valve or valve-in-ring procedure, part 1.

Science.gov (United States)

Bapat, Vinnie; Pirone, Francesco; Kapetanakis, Stam; Rajani, Ronak; Niederer, Steven

2015-10-01

To determine the factors influencing left ventricular outflow tract (LVOT) area reduction after a mitral valve-in-valve (VIV) or a valve-in-ring (VIR) procedure. Transcatheter heart valves (THVs) are increasingly used in performing a VIV or a VIR procedure in high-risk patients. Although less invasive, a potential complication is LVOT obstruction. However, the factors predisposing to LVOT obstruction are ill defined. To understand the effects of the various factors, the study was carried out in three parts: To understand the effect of VIV and VIR on reduction in LVOT area with special attention to different surgical heart valve (SHV) orientations and depth of THV implant. This was carried out in porcine and cadaver hearts. To quantify aorto-mitral-annular (AMA) angle in 20 patients with or without mitral disease and to derive a static computational model to predict LVOT obstruction. To study the effect of SHV design on LVOT obstruction after VIV. This was carried out as a bench test. LVOT area reduction was similar after VIV irrespective of orientation of the mitral SHV implantation as it pinned open the SHV leaflets. Similar effect was seen after VIR. The degree of LVOT obstruction was partly determined by AMAangle and was inversely proportional. SHV design, ring design, and depth of SPAIEN XT implantation also had effect on LVOT obstruction. A possibility of LVOT obstruction should be considered when performing a VIV and VIR procedure. Type of SHV, flexible ring, less obtuse AMA angle, and depth of SAPIEN XT implant can influence the risk. © 2015 Wiley Periodicals, Inc.

Electrical stress and strain in lunar regolith simulants

Science.gov (United States)

Marshall, J.; Richard, D.; Davis, S.

2011-11-01

Experiments to entrain dust with electrostatic and fluid-dynamic forces result in particulate clouds of aggregates rather than individual dust grains. This is explained within the framework of Griffith-flaw theory regarding the comminution/breakage of weak solids. Physical and electrical inhomogeneities in powders are equivalent to microcracks in solids insofar as they facilitate failure at stress risers. Electrical charging of powders induces bulk sample stresses similar to mechanical stresses experienced by strong solids, depending on the nature of the charging. A powder mass therefore "breaks" into clumps rather than separating into individual dust particles. This contrasts with the expectation that electrical forces on the Moon will eject a submicron population of dust from the regolith into the exosphere. A lunar regolith will contain physical and electrostatic inhomogeneities similar to those in most charged powders.

Modeling the interference of vortex-induced vibration and galloping for a slender rectangular prism

Science.gov (United States)

Mannini, Claudio; Massai, Tommaso; Marra, Antonino Maria

2018-04-01

Several bluff bodies in an airflow, such as rectangular cylinders with moderate side ratio, in particular conditions of mass and damping can experience the interference of vortex-induced vibration (VIV) and galloping. This promotes a combined instability, which one may call "unsteady galloping", with peculiar features and possibly large vibration amplitudes in flow speed ranges where no excitation is predicted by classical theories. The mathematical model proposed between the 70's and the 80's by Prof. Y. Tamura to simulate this phenomenon was considered here for the case study of a two-dimensional rectangular cylinder with a side ratio of 1.5, having the shorter section side perpendicular to the smooth airflow. This wake-oscillator model relies on the linear superposition of the unsteady wake force producing VIV excitation and the quasi-steady force that is responsible for galloping. The model formulation was slightly modified, and the way to determine a crucial parameter was changed, revealing a previously unexplored behavior of the equations. In the present form, the model is able to predict the dynamic response of the rectangular cylinder with a satisfactory qualitative and, to a certain extent, quantitative agreement with the experimental data, although the limitations of the present approach are clearly highlighted in the paper. The mathematical modeling of unsteady galloping and the analysis of the results offer a deep insight into this complicated phenomenon and its nonlinear features. The model also represents a useful engineering tool to estimate the vibration of a structure or structural element for which the interference of VIV and galloping is envisaged.

Análise da percepção de risco e vulnerabilidade a partir dos alunos do ensino médio na vivência de Nova Friburgo RJ após desastre natural de 2011

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Denise Gonzalez

2016-06-01

Full Text Available A precipitação intensa num intervalo de poucas horas, causou uma série de deslizamentos de encostas e enchentes e/ou inundações de rios na Região Serrana do Estado do Rio de Janeiro, Brasil, especialmente no município de Nova Friburgo no mês de janeiro de 2011. Baseada na vivência dos alunos do 1º ano do Ensino Médio de dois colégios da rede estadual de ensino, esta pesquisa se utilizou do fato desta região ter sofrido este evento extremo. Observou-se a percepção de risco dos alunos através do que viveram e com os conteúdos da geografia Com o aplicativo Google Earth,foi elaborado o mapa de área de risco pelos mesmos, havendo uma comparação entre os resultados encontrados nas duas escolas, além de confrontá-los com dados da prefeitura sobre o assunto. Além disso, houve a análise da vulnerabilidade da população a partir de mapas temáticos com base no censo do IBGE(2010.

Test procedure for calibration, grooming and alignment of the LDUA Optical Alignment Scope

International Nuclear Information System (INIS)

Potter, J.D.

1995-01-01

The Light Duty Utility Arm (LDUA) is a remotely operated manipulator used to enter into underground waste tanks through one of the tank risers. The LDUA must be carefully aligned with the tank riser during the installation process. The Optical Alignment Scope (OAS) is used to determine when optimum alignment has been achieved between the LDUA and the riser. This procedure is used to assure that the instrumentation and equipment comprising the OAS is properly adjusted in order to achieve its intended functions successfully

Psicologia e atenção básica: vivências de estagiários na Estratégia de Saúde da Família Psychology and basic attention: experiences of trainees in Family Health Strategy

Directory of Open Access Journals (Sweden)

Valdemar Donizeti de Sousa

2009-10-01

Full Text Available Trata-se de uma pesquisa qualitativa de inspiração teórica humanista acerca das vivências de estagiários do curso de graduação em psicologia da PUC-Campinas na área da Saúde/Clínica, na atenção básica em saúde pública, como participantes de equipes de saúde da família. Participaram seis estagiários do último ano do curso, alocados em dois Centros de Saúde-Escola da região Noroeste de Campinas. A metodologia utilizada foi de cunho etnográfico. O processo para composição dos dados foi produzido em dois momentos: a registro semanal em diário pessoal de cada estagiário, durante cinco meses; b entrevistas individuais, semidirigidas, ao final do período letivo. Estes dados foram analisados a partir de uma leitura fenomenológica. Encontraram-se fases evolutivas no processo de formação do estagiário. Inicialmente, a experiência foi vivenciada com surpresa e estranhamento, gerando sentimentos contraditórios de inadequação frente à inexperiência para o trabalho em equipe. No entanto, por terem sido acolhidos e compreendidos pela equipe, ocorreu uma transformação de natureza pessoal e formativa, considerada muito enriquecedora, simbolizada como vivência singular de pertencimento, motivando esforços para prática clínica integradora e criativa.This study shows a qualitative research based on a humanist theory in relation to the experiences of trainees from the psychology course of PUC-Campinas, that are participating in family health teams in the areas of Health/Clinic and basic attention in public health. The participants were six trainees in the last year of the course and located in two Health-School Centers in the Northwest region of Campinas. The methodology used was an ethnographic view. The processes of data composition were produced in two different moments: a by weekly register on the trainee's personal diary during five months; b semi-directed individual interviews at the end of the term. These data were

Refining fault slip rates using multiple displaced terrace risers—An example from the Honey Lake fault, NE California, USA

Science.gov (United States)

Gold, Ryan D.; Briggs, Richard; Crone, Anthony J.; Duross, Christopher

2017-01-01

Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4 difference observed globally) produce large uncertainties in the slip-rate estimate. In this investigation, we explore how the full range of displacements and bounding ages from multiple faulted terrace risers can be combined to yield a more accurate fault slip rate. We use 0.25-m cell size digital terrain models derived from airborne lidar data to analyze three sites where terrace risers are offset right-laterally by the Honey Lake fault in NE California, USA. We use ages for locally extensive subhorizontal surfaces to bracket the time of riser formation: an upper surface is the bed of abandoned Lake Lahontan having an age of 15.8 ± 0.6 ka and a lower surface is a fluvial terrace abandoned at 4.7 ± 0.1 ka. We estimate lateral offsets of the risers ranging between 6.6 and 28.3 m (median values), a greater than fourfold difference in values. The amount of offset corresponds to the riser's position relative to modern stream meanders: the smallest offset is in a meander cutbank position, whereas the larger offsets are in straight channel or meander point-bar positions. Taken in isolation, the individual terrace-riser offsets yield slip rates ranging from 0.3 to 7.1 mm/a. However, when the offset values are collectively assessed in a probabilistic framework, we find that a uniform (linear) slip rate of 1.6 mm/a (1.4–1.9 mm/a at 95% confidence) can satisfy the data, within their respective uncertainties. This investigation demonstrates that integrating observations of multiple offset elements (crest, midpoint, and base) from numerous faulted and dated terrace risers at closely spaced

Transient effects of tendon disconnection on the survivability of a TLP in moderate-strength hurricane conditions

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Moo Hyun Kim

2009-09-01

Full Text Available The primary objective of this paper is to investigate the dynamic stability and survivability of a four-column classic TLP (tension-leg platform under less-than-extreme storm conditions where one or more tendons have been lost due to damage or disconnect. The transient responses of the platform and tendon tensions at the moment of disconnection are particularly underscored. The numerical simulation is based on the BE-FE hybrid hull-tendon-riser coupled dynamic analysis in time domain. Compared to the common industry practice of checking the system without a failed tendon in the beginning, the maximum tension on the neighboring tendon can be significantly increased at the moment of disconnection due to the snap-like transient effects, which can lead to unexpected failure of the total system. It is also found that the transient effects can be reduced with the presence of TTRs (top-tensioned risers with pneumatic tensioners. It is also seen that the TLP cannot survive in the 100-yr hurricane condition after losing one tendon.

INVESTIGATING SUSPENSION OF MST SLURRIES IN A PILOT-SCALE WASTE TANK

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Restivo, M.; Steeper, T.; Williams, M.; Qureshi, Z.

2011-01-24

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is for the pumps to suspend the MST particles so that MST can be removed from the tank. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5 and B2 for two pump configurations and Risers B5, B3, and B1 for three pump configurations).

A Novel Wake Oscillator Model for Vortex-Induced Vibrations Prediction of A Cylinder Considering the Influence of Reynolds Number

Science.gov (United States)

Gao, Xi-feng; Xie, Wu-de; Xu, Wan-hai; Bai, Yu-chuan; Zhu, Hai-tao

2018-04-01

It is well known that the Reynolds number has a significant effect on the vortex-induced vibrations (VIV) of cylinders. In this paper, a novel in-line (IL) and cross-flow (CF) coupling VIV prediction model for circular cylinders has been proposed, in which the influence of the Reynolds number was comprehensively considered. The Strouhal number linked with the vortex shedding frequency was calculated through a function of the Reynolds number. The coefficient of the mean drag force was fitted as a new piecewise function of the Reynolds number, and its amplification resulted from the CF VIV was also taken into account. The oscillating drag and lift forces were modelled with classical van der Pol wake oscillators and their empirical parameters were determined based on the lock-in boundaries and the peak-amplitude formulas. A new peak-amplitude formula for the IL VIV was developed under the resonance condition with respect to the mass-damping ratio and the Reynolds number. When compared with the results from the experiments and some other prediction models, the present model could give good estimations on the vibration amplitudes and frequencies of the VIV both for elastically-mounted rigid and long flexible cylinders. The present model considering the influence of the Reynolds number could generally provide better results than that neglecting the effect of the Reynolds number.

Influence of Membrane Equivalent Weight and Reinforcement on Ionic Species Crossover in All-Vanadium Redox Flow Batteries.

Science.gov (United States)

Ashraf Gandomi, Yasser; Aaron, Doug S; Mench, Matthew M

2017-06-06

One of the major sources of lost capacity in all-vanadium redox flow batteries (VRFBs) is the undesired transport (usually called crossover) of water and vanadium ions through the ion-exchange membrane. In this work, an experimental assessment of the impact of ion-exchange membrane properties on vanadium ion crossover and capacity decay of VRFBs has been performed. Two types of cationic membranes (non-reinforced and reinforced) with three equivalent weights of 800, 950 and 1100 g·mol -1 were investigated via a series of in situ performance and capacity decay tests along with ex situ vanadium crossover measurement and membrane characterization. For non-reinforced membranes, increasing the equivalent weight (EW) from 950 to 1100 g·mol -1 decreases the V(IV) permeability by ~30%, but increases the area-specific resistance (ASR) by ~16%. This increase in ASR and decrease in V(IV) permeability was accompanied by increased through-plane membrane swelling. Comparing the non-reinforced with reinforced membranes, membrane reinforcement increases ASR, but V(IV) permeability decreases. It was also shown that there exists a monotonic correlation between the discharge capacity decay over long-term cycling and V(IV) permeability values. Thus, V(IV) permeability is considered a representative diagnostic for assessing the overall performance of a particular ion-exchange membrane with respect to capacity fade in a VRFB.

Valor e significado da vivência no primeiro ano do curso de medicina: apreciação de aprendizado pessoal e contexto em uma série histórica

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Dejano T. Sobral

Full Text Available Os propósitos do trabalho foram examinar as percepções dos alunos sobre a vivência inicial do curso de Medicina, mediante o Questionário de Valoração do Curso (QVC, bem como analisar relações entre índices do QVC e medidas de atributos pessoais e sucesso acadêmico. O estudo envolveu 609 alunos numa década. Os resultados revelaram relativa estabilidade dos escores do QVC em turmas consecutivas e diferenças significantes entre os alunos agrupados por sexo, naturalidade, categoria de preferência por carreira e semestre de acesso ao curso. Verificaram-se, também, associações significantes entre escores do QVC e medidas de autoconfiança, intenção de aprender, rendimento cognitivo e atividade de monitoria em quatro semestres seguidos. Testes do Modelo Linear Geral revelaram quatro fatores independentes principais na explicação da variabilidade do escore do QVC: intenção de aprender, autoconfiança, preferência por carreira e semestre de acesso. A discussão examina os achados em conexão com noções de contexto interno do aprendiz e ambiência educacional. Concluindo, as respostas ao QVC refletem a perspectiva de valoração do aprendizado pessoal na interação com as dimensões do contexto educacional. O instrumento tem, assim, utilidade no acompanhamento pedagógico da iniciação profissional.

Fluid-to-fluid scaling for a gravity- and flashing-driven natural circulation loop

International Nuclear Information System (INIS)

Yadigaroglu, G.; Zeller, M.

1994-01-01

In certain natural-circulation reactor systems proposed recently, vapor generation takes place by flashing in an adiabatic riser above the core. A step-by-step facility design procedure was used to define suitable scaling criteria for a refrigerant-113 (R-113) experiment simulating the dynamics and stability of such a loop. The fact that vapor generation does not normally take place in the core allows additional flexibility in designing the model; almost perfect simulation can be achieved, mainly by reducing the height of the facility according to the liquid density ratio and scaling for similar void fraction distributions in the prototype and the model. ((orig.))

Fluidization behavior in a circulating slugging fluidized bed reactor. Part I : residence time and residence time distribution of polyethylene solids

NARCIS (Netherlands)

Putten, van I.C.; Sint Annaland, van M.; Weickert, G.

2007-01-01

Square nosed slugging fluidization behavior in a circulating fluidized bed riser using a polyethylene powder with a very wide particle size distribution was studied. In square nosed slugging fluidization the extent of mixing of particles of different size depends on the riser diameter, gas velocity,

Fluidization behavior in a circulating slugging fluidized bed reactor. Part I: Residence time and residence time distribution of polyethylene solids

NARCIS (Netherlands)

van Putten, I.C.; van Sint Annaland, M.; Weickert, G.

2007-01-01

Square nosed slugging fluidization behavior in a circulating fluidized bed riser using a polyethylene powder with a very wide particle size distribution was studied. In square nosed slugging fluidization the extent of mixing of particles of different size depends on the riser diameter, gas velocity,

Analysis of BY-106 pump pit cover plate

International Nuclear Information System (INIS)

Coverdell, B.L.

1994-01-01

A new cover for the pump pit of Tank 241-BY-106 has been designed to allow the rotary core exhauster to be hooked up without requiring pit entry, riser modification, or equipment removal. The new pit cover is necessary to allow installation of two risers for reducing exposure, contamination, and waste. Computer analysis indicates that the safety margin of the pit cover plate with two risers is adequate. The computer stress model and input files are attached. The pit cover plate is a replacement for an existing plate; therefore seismic and wind loads were considered for the plate only

Overview of Emic Triggered Chorus Emissions in Cluster Data

Science.gov (United States)

Grison, B.; Pickett, J. S.; Omura, Y.; Santolik, O.; Engebretson, M. J.; Dandouras, I. S.; Masson, A.; Decreau, P. M.; Adrian, M. L.; Cornilleau Wehrlin, N.

2010-12-01

Electromagnetic ion cyclotron (EMIC) triggered emissions have been recently observed onboard the Cluster spacecraft close to the plasmapause in the equatorial region of the magnetosphere (Pickett et al., 2010). The nonlinear mechanism of the wave amplification is the same as for the well known whistler-mode chorus emissions (Omura et al., 2010). The EMIC triggered emissions appear as risers: electromagnetic structures that have a positive frequency drift with time. They can thus be considered as the EMIC analogue of rising frequency whistler-mode chorus emissions. In addition, they propagate away from the magnetic equator. These EMIC risers are not common in Cluster data. We present an overview of the properties of all the identified cases. Risers can be sorted out in two groups: in the first one the starting frequency of EMIC emissions is close to one half of the local proton gyrofrequency and the risers have a clear left-hand polarization. In the second group the risers have an opposite polarization with a starting frequency close to one half of the He+ gyrofrequency. Most of the cases have been detected close to 22 MLT (magnetic local time). This dependence will be investigated to determine if it is linked to the orbit effects or if there is a physical cause.

Parametric study on the behavior of an innovative subsurface tension leg platform in ultra-deep water

Science.gov (United States)

Zhen, Xing-wei; Huang, Yi

2017-10-01

This study focuses on a new technology of Subsurface Tension Leg Platform (STLP), which utilizes the shallowwater rated well completion equipment and technology for the development of large oil and gas fields in ultra-deep water (UDW). Thus, the STLP concept offers attractive advantages over conventional field development concepts. STLP is basically a pre-installed Subsurface Sea-star Platform (SSP), which supports rigid risers and shallow-water rated well completion equipment. The paper details the results of the parametric study on the behavior of STLP at a water depth of 3000 m. At first, a general description of the STLP configuration and working principle is introduced. Then, the numerical models for the global analysis of the STLP in waves and current are presented. After that, extensive parametric studies are carried out with regarding to SSP/tethers system analysis, global dynamic analysis and riser interference analysis. Critical points are addressed on the mooring pattern and riser arrangement under the influence of ocean current, to ensure that the requirements on SSP stability and riser interference are well satisfied. Finally, conclusions and discussions are made. The results indicate that STLP is a competitive well and riser solution in up to 3000 m water depth for offshore petroleum production.

Hysteresis Phenomena in Sulfur Dioxide Oxidation over Supported Vanadium Catalysts

DEFF Research Database (Denmark)

Masters, Stephen G.; Eriksen, Kim Michael; Fehrmann, Rasmus

1997-01-01

Catalyst deactivation and hysteresis behavior in industrial SO2-oxidation catalysts have been studied in the temperature region 350-480 C by combined in situ EPR spectroscopy and catalytic activity measurements. The feed gas composition simulated sulfuric acid synthesis gas and wet/dry de......NOx'ed flue gas. The vanadium (IV) compound K4(VO)3(SO4)5 precipitated during all the investigated conditions hence causing catalyst deactivation. Hysteresis behavior of both the catalytic activity and the V(IV) content was observed during reheating....

Supra-annular Valve-in-Valve implantation reduces blood stasis on the transcatheter aortic valve leaflets.

Science.gov (United States)

Vahidkhah, Koohyar; Azadani, Ali N

2017-06-14

Leaflet thrombosis following transcatheter aortic valve replacement (TAVR) and Valve-in-Valve (ViV) procedures has been increasingly recognized. This study aimed to investigate the effect of positioning of the transcatheter aortic valve (TAV) in ViV setting on the flow dynamics aspect of post-ViV thrombosis by quantifying the blood stasis in the intra-annular and supra-annular settings. To that end, two idealized computational models, representing ViV intra-annular and supra-annular positioning of a TAV were developed in a patient-specific geometry. Three-dimensional flow fields were then obtained via fluid-solid interaction modeling to study the difference in blood residence time (BRT) on the TAV leaflets in the two settings. At the end of diastole, a strip of high BRT (⩾1.2s) region was observed on the TAV leaflets in the ViV intra-annular positioning at the fixed boundary where the leaflets are attached to the frame. Such a high BRT region was absent on the TAV leaflets in the supra-annular positioning. The maximum value of BRT on the surface of non-, right, and left coronary leaflets of the TAV in the supra-annular positioning were 53%, 11%, and 27% smaller compared to the intra-annular positioning, respectively. It was concluded that the geometric confinement of TAV by the leaflets of the failed bioprosthetic valve in ViV intra-annular positioning increases the BRT on the leaflets and may act as a permissive factor in valvular thrombosis. The absence of such a geometric confinement in the ViV supra-annular positioning leads to smaller BRT and subsequently less likelihood of leaflet thrombosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Autonomous Optimization of a Solidification Pattern and Its Effect on Porosity and Segregation in Steel Castings

DEFF Research Database (Denmark)

Kotas, Petr; Tutum, Cem Celal; Hattel, Jesper Henri

2011-01-01

The present paper considers optimization of a solidification pattern of a gravity sand-cast steel part. That is, the choice of proper riser and chill designs has been investigated using genetic algorithms while simultaneously considering their impact on centerline porosity and macrosegregation...... distribution. This was accomplished by coupling a casting simulation software package with an optimization module. The casting process of the original casting design was simulated using a transient 3D thermal model incorporated in a commercial simulation software package to determine potential flaws...... and inadequacies. After this initial assessment, a new geometrical model was suggested with the redesigned gating system and rearranged chills to obtain better filling and solidification patterns. Based on the improved model, relevant optimization targets and constraints were defined. One multi...

Design and experimental analysis of broadband energy harvesting from vortex-induced vibrations

Science.gov (United States)

Zhang, L. B.; Abdelkefi, A.; Dai, H. L.; Naseer, R.; Wang, L.

2017-11-01

In this paper, an operable strategy to enhance the output power of piezoelectric energy harvesting from vortex-induced vibration (VIV) using nonlinear magnetic forces is proposed for the first time. Two introduced small magnets with a repulsive force are, respectively, attached on a lower support and the bottom of a circular cylinder which is subjected to a uniform wind speed. Experiments show that the natural frequency of the VIV-based energy harvester is significantly changed by varying the relative position of the two magnets and hence the synchronization region is shifted. It is observed that the proposed energy harvester displays a softening behavior due to the impact of nonlinear magnetic forces, which greatly increases the performance of the VIV-based energy harvesting system, showing a wider synchronization region and a higher level of the harvested power by 138% and 29%, respectively, compared to the classical configuration. This proposed design can provide the groundwork to promote the output power of conventional VIV-based piezoelectric generators, further enabling to realize self-powered systems.

Caractérisation des peuplements ligneux des parcs à Faidherbia ...

African Journals Online (AJOL)

SARAH

31 oct. 2015 ... Objectif : cette étude vise à caractériser les peuplements ligneux des parcs à Faidherbia albida .... domaine Sud-Sahélien Central dominé par les ... caractériser le climat. ..... Surface terrière (St) : La surface terrière globale ou.

Cronobiologia e suas Influências nas Vivências de Lazer

Directory of Open Access Journals (Sweden)

Bianca Araujo Pizzolito

2012-04-01

Full Text Available Resumo

A exclusão no lazer, em geral, é estudada a partir de diversas variáveis, sendo as mais clássicas: renda, gênero, idade, escolaridade e inserção espacial. Este estudo abordou outra variável: a relação sono/vigília, questão estudada diretamente pela cronobiologia, área que estuda os ritmos biológicos, caracterizando os seres humanos em matutinos, vespertinos ou intermediários. O estudo verificou os possíveis impactos que esses ritmos biológicos exercem sobre o lazer dos indivíduos, assim como, as possíveis reordenações diárias das atividades de trabalho e lazer a que são submetidos por esta condição. O método utilizado foi a história oral, com a coleta de dados realizada por meio das técnicas da historia oral temática, contando com um roteiro de temas, entrevistas gravadas e transcritas. As principais considerações foram: uma vez que os horários sociais são essencialmente diurnos, os indivíduos matutinos não apontaram grande dificuldade em (re organizar seus horários, para esses indivíduos as vivências de lazer noturnas ficam restritas, geralmente, a eventos de cunho social, enquanto as atividades de lazer pela manhã são mais individuais. Enquanto que com as pessoas vespertinas, foi possível identificar maior dificuldade de adequação aos horários sociais e um esforço de adaptação dos horários de maior disposição com os de produtividade. As atividades de lazer coincidiam com a oferta social de lazer, geralmente, nos períodos da tarde e da noite. Desta forma, verificou-se que embora exista um horário social, do qual participam diferentes indivíduos, existem características de um lazer matutino e um vespertino que são sustentadas no cotidiano e nos discursos.