Time-Domain Simulation of Subsea Equipments Installation Using Hydrodynamic Derivatives

2020 ◽  
Author(s):  
Emerson M. de Andrade ◽  
Joel S. Sales ◽  
Antonio C. Fernandes ◽  
Mario L. Ribeiro ◽  
Pedro V. Teixeira
Keyword(s):  
Hydrodynamic Forces ◽  
Dynamic Responses ◽  
Elastic Behavior ◽  
Strong Interactions ◽  
Small Scale ◽  
Complex Geometries ◽  
Second Phase ◽  
Current Profile ◽  
Resonance Effects ◽  
Hydrodynamic Derivatives

Abstract The installation of a subsea equipment such as manifold needs careful planning and coordination. Studies on the behavior of the dynamic responses are crucial to guarantee safety. Some important factors in these operations include the current profile, waves characteristics, winches motions at topside, and the elastic behavior of the cable (due to resonance effects). Currently, most of the available commercial codes use simplified models for the hydrodynamic forces of submerged equipment. However, for cases with complex geometries and strong interactions with the environmental loads, those models fail to represent correctly the dynamics. In this paper we present an initial method and a hydrodynamic model to include terms that allow the modelling of complex behavior of submerged complex geometries by using hydrodynamic derivatives extracted from model tests. To verify the procedure, tests were performed both at a flume tank and at a towing tank. The model was implemented in a commercial code by using a Simplified Buoy model, to which a python procedure that calculated the hydrodynamic forces was attached. The study was divided into two phases: the first one consisted of the verification of the effectiveness of the external routine. This was done for a manifold in 1DOF and then in 6 DOF. In the second phase, the dynamic maneuvering model using Hydrodynamic Derivatives was implemented as an external routine and, using the output from dynamic excitation experiments at small scale with a manifold, kinematical behavior results were compared. Results showed good adherence, although some further investigations are still needed.

scholarly journals Multiscale Mountain Waves Influencing a Major Orographic Precipitation Event

2007 ◽  
Vol 64 (3) ◽  
pp. 711-737 ◽  
Author(s):  
Matthew F. Garvert ◽  
Bradley Smull ◽  
Cliff Mass
Keyword(s):  
Mesoscale Model ◽  
Precipitation Forecast ◽  
Precipitation Event ◽  
Small Scale ◽  
Second Phase ◽  
Mountain Waves ◽  
Low Level ◽  
Orographic Rainfall ◽  
Vertically Propagating ◽  
Horizontal Wavelength

Abstract This study combines high-resolution mesoscale model simulations and comprehensive airborne Doppler radar observations to identify kinematic structures influencing the production and mesoscale distribution of precipitation and microphysical processes during a period of heavy prefrontal orographic rainfall over the Cascade Mountains of Oregon on 13–14 December 2001 during the second phase of the Improvement of Microphysical Parameterization through Observational Verification Experiment (IMPROVE-2) field program. Airborne-based radar detection of precipitation from well upstream of the Cascades to the lee allows a depiction of terrain-induced wave motions in unprecedented detail. Two distinct scales of mesoscale wave–like air motions are identified: 1) a vertically propagating mountain wave anchored to the Cascade crest associated with strong midlevel zonal (i.e., cross barrier) flow, and 2) smaller-scale (<20-km horizontal wavelength) undulations over the windward foothills triggered by interaction of the low-level along-barrier flow with multiple ridge–valley corrugations oriented perpendicular to the Cascade crest. These undulations modulate cloud liquid water (CLW) and snow mixing ratios in the fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5), with modeled structures comparing favorably to radar-documented zones of enhanced reflectivity and CLW measured by the NOAA P3 aircraft. Errors in the model representation of a low-level shear layer and the vertically propagating mountain waves are analyzed through a variety of sensitivity tests, which indicated that the mountain wave’s amplitude and placement are extremely sensitive to the planetary boundary layer (PBL) parameterization being employed. The effects of 1) using unsmoothed versus smoothed terrain and 2) the removal of upstream coastal terrain on the flow and precipitation over the Cascades are evaluated through a series of sensitivity experiments. Inclusion of unsmoothed terrain resulted in net surface precipitation increases of ∼4%–14% over the windward slopes relative to the smoothed-terrain simulation. Small-scale waves (<20-km horizontal wavelength) over the windward slopes significantly impact the horizontal pattern of precipitation and hence quantitative precipitation forecast (QPF) accuracy.

Differences in the Upscaling Procedure for Compositional Reservoir Simulations of Immiscible and Miscible Gas Flooding

2021 ◽  
Author(s):  
Victor de Souza Rios ◽  
Arne Skauge ◽  
Ken Sorbie ◽  
Gang Wang ◽  
Denis José Schiozer ◽  
...  
Keyword(s):  
Computational Cost ◽  
Specific Treatment ◽  
Dynamic Responses ◽  
Scale Model ◽  
Small Scale ◽  
Coarse Scale ◽  
Reservoir Models ◽  
Permeability Upscaling ◽  
Gas Flooding ◽  
Grid Block

Abstract Compositional reservoir simulation is essential to represent the complex interactions associated with gas flooding processes. Generally, an improved description of such small-scale phenomena requires the use of very detailed reservoir models, which impact the computational cost. We provide a practical and general upscaling procedure to guide a robust selection of the upscaling approaches considering the nature and limitations of each reservoir model, exploring the differences between the upscaling of immiscible and miscible gas injection problems. We highlight the different challenges to achieve improved upscaled models for immiscible and miscible gas displacement conditions with a stepwise workflow. We first identify the need for a special permeability upscaling technique to improve the representation of the main reservoir heterogeneities and sub-grid features, smoothed during the upscaling process. Then, we verify if the use of pseudo-functions is necessary to correct the multiphase flow dynamic behavior. At this stage, different pseudoization approaches are recommended according to the miscibility conditions of the problem. This study evaluates highly heterogeneous reservoir models submitted to immiscible and miscible gas flooding. The fine models represent a small part of a reservoir with a highly refined set of grid-block cells, with 5 × 5 cm2 area. The upscaled coarse models present grid-block cells of 8 × 10 m2 area, which is compatible with a refined geological model in reservoir engineering studies. This process results in a challenging upscaling ratio of 32 000. We show a consistent procedure to achieve reliable results with the coarse-scale model under the different miscibility conditions. For immiscible displacement situations, accurate results can be obtained with the coarse models after a proper permeability upscaling procedure and the use of pseudo-relative permeability curves to improve the dynamic responses. Miscible displacements, however, requires a specific treatment of the fluid modeling process to overcome the limitations arising from the thermodynamic equilibrium assumption. For all the situations, the workflow can lead to a robust choice of techniques to satisfactorily improve the coarse-scale simulation results. Our approach works on two fronts. (1) We apply a dual-porosity/dual-permeability upscaling process, developed by Rios et al. (2020a), to enable the representation of sub-grid heterogeneities in the coarse-scale model, providing consistent improvements on the upscaling results. (2) We generate specific pseudo-functions according to the miscibility conditions of the gas flooding process. We developed a stepwise procedure to deal with the upscaling problems consistently and to enable a better understanding of the coarsening process.

Modeling pseudo-elastic behavior in small-scale ThCr2Si2-type crystals

2018 ◽  
Vol 150 ◽  
pp. 86-95 ◽  
Author(s):  
Ian N. Bakst ◽  
John T. Sypek ◽  
James R. Neilson ◽  
Seok-Woo Lee ◽  
Christopher R. Weinberger
Keyword(s):  
Elastic Behavior ◽  
Small Scale

scholarly journals The Development of an Android-Based Dictionary for Blind

2020 ◽  
Vol 14 (11) ◽  
pp. 76
Author(s):  
Novi Eka Susilowati ◽  
Imam Syafi'i ◽  
Aftina Aftina ◽  
Azzhan Syahrul ◽  
Dwi Prasetyo Nogroho ◽  
...  
Keyword(s):  
Product Development ◽  
Scale Validation ◽  
Visual Impairments ◽  
Development Model ◽  
Small Scale ◽  
Second Phase ◽  
Voice Input ◽  
Average Percentage ◽  
Input And Output

This study aims to develop an Android-based Indonesian dictionary for the blind. This study was developed using the Borg & Gall development model with some adjustments to the needs of this study. The stages of product development are (1) preliminary studies, (2) planning, (3) product development, (4) product validation, (5) first phase revision, (6) trials, (7) second phase revision, and (8) dissemination. The product developed is an android-based dictionary application with voice input and output. This developed product has been validated and tested on a small scale. Validation is carried out for material expert validators, media experts, and practitioners; while small-scale trials were conducted on 5 people with visual impairments. The results of product validation and trial show that the product developed is feasible to be implemented with an average percentage rating of 91.93%. The product developed provides benefits to the blind, which makes it easier to understand the meaning of words in the dictionary and increases the independence of the blind.

Development of Computer Vision Technique for in Situ Soil Characterization

1996 ◽  
Vol 1526 (1) ◽  
pp. 86-97 ◽  
Author(s):  
Roman D. Hryciw ◽  
Scott A. Raschke
Keyword(s):  
Computer Vision ◽  
Vision System ◽  
Cohesionless Soil ◽  
Software Systems ◽  
Small Scale ◽  
Second Phase ◽  
Video Images ◽  
Subsurface Soil ◽  
Different Levels

Construction and rehabilitation of highways, tunnels, and bridges require detailed information about subsurface stratigraphy. This study presents development of a new method for characterizing subsurface soil in situ using computer vision. Hardware and software systems are integrated to obtain the grain-size distribution (GSD) of subsurface soils continuously with depth and to identify small-scale subsurface anomalies. Research is being conducted in three phases. The first phase consists of measuring the GSD of detached cohesionless soil specimens in the laboratory from digital images obtained with a computer vision system (CVS). The second phase uses the CVS to develop image processing and analysis techniques to classify soil assemblies in the laboratory and identify subsurface anomalies by simulating the manner in which images will be acquired in situ. A texture analysis approach has been developed that can detect changes in stratigraphy. The technique has been successful in identifying different types of dry, uniformly graded soils. Finally, a subsurface vision probe is being designed and constructed that will capture video images at three different levels of magnification continuously with depth.

scholarly journals Mechanically interlocked 3D multi-material micromachines

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
C. C. J. Alcântara ◽  
F. C. Landers ◽  
S. Kim ◽  
C. De Marco ◽  
D. Ahmed ◽  
...  
Keyword(s):  
Drug Loading ◽  
Three Dimensional ◽  
Dissimilar Materials ◽  
Elastic Behavior ◽  
Small Scale ◽  
Shape Transformation ◽  
On Demand ◽  
Mold Casting ◽  
Metal Organic ◽  
Novel Applications

AbstractMetals and polymers are dissimilar materials in terms of their physicochemical properties, but complementary in terms of functionality. As a result, metal-organic structures can introduce a wealth of novel applications in small-scale robotics. However, current fabrication techniques are unable to process three-dimensional metallic and polymeric components. Here, we show that hybrid microstructures can be interlocked by combining 3D lithography, mold casting, and electrodeposition. Our method can be used to achieve complex multi-material microdevices with unprecedented resolution and topological complexity. We show that metallic components can be combined with structures made of different classes of polymers. Properties of both metals and polymers can be exploited in parallel, resulting in structures with high magnetic responsiveness, elevated drug loading capacity, on-demand shape transformation, and elastic behavior. We showcase the advantages of our approach by demonstrating new microrobotic locomotion modes and controlled agglomeration of swarms.

Plastic Stress Intensity Factors for Small Scale Yielding in Antiplane Shear by Caustics

1982 ◽  
Vol 49 (4) ◽  
pp. 754-760 ◽  
Author(s):  
P. S. Theocaris ◽  
C. I. Razem
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Crack Tip ◽  
Antiplane Shear ◽  
Elastic Behavior ◽  
Small Scale ◽  
Small Scale Yielding ◽  
Scale Yielding ◽  
Plastic Stress

The KIII-stress intensity factor in an edge-cracked plate submitted to antiplane shear may be evaluated by the reflected caustic created around the crack tip, provided that a purely elastic behavior exists at the crack tip [1]. For a work-hardening, elastic-plastic material, when stresses at the vicinity of the crack tip exceed the yield limit of the material, the new shape of caustic differs substantially from the corresponding shape of the elastic solution. In this paper the shape and size of the caustics created at the tip of the crack, when small-scale yielding is established in the vicinity of the crack tip, were studied, based on a closed-form solution introduced by Rice [2]. The plastic stress intensity factor may be evaluated from the dimensions of the plastic caustic. Experimental evidence with cracked plates made of opaque materials, like steel, corroborated the results of the theory.

Superimposed Deformations in the Missi Meta-sedimentary Rocks near Flin Flon, Manitoba

1971 ◽  
Vol 8 (2) ◽  
pp. 217-242 ◽  
Author(s):  
Mel R. Stauffer ◽  
Amar Mukherjee
Keyword(s):  
Sedimentary Rocks ◽  
Greenschist Facies ◽  
Axial Plane ◽  
Small Scale ◽  
Second Phase ◽  
Retrograde Metamorphism ◽  
High Angle ◽  
South Side ◽  
Flin Flon

Within the Flin Flon Basin, Precambrian meta-sandstones and conglomerates belonging to the Missi Group have been complexly deformed as a result of three periods of deformation. The first two periods (P1 and P2) involved folding but no apparent faulting, the last (P3) involved both folding and faulting. Progressive metamorphism (M2), within the greenschist facies, occurred during the second phase (P2) and aided in the formation of a pronounced axial-plane foliation (S2). Small-scale folding and retrograde metamorphism (M3) occurred along faults formed during the last phase (P3).The faults in this area all appear to be high angle, oblique-slip reverse faults and can be interpreted as having formed during a single orogenic event (P3) although there is sequence in their initiation. The net-slip directions of different faults are approximately the same, and plunge moderately to the southeast, with either the east or south side upthrown, depending on the attitude of the fault.

scholarly journals Gloxinia—An Open-Source Sensing Platform to Monitor the Dynamic Responses of Plants

Sensors ◽  
2020 ◽  
Vol 20 (11) ◽  
pp. 3055
Author(s):  
Olivier Pieters ◽  
Tom De Swaef ◽  
Peter Lootens ◽  
Michiel Stock ◽  
Isabel Roldán-Ruiz ◽  
...  
Keyword(s):  
Open Source ◽  
Large Scale ◽  
Environmental Changes ◽  
Low Cost ◽  
Current Data ◽  
Dynamic Responses ◽  
Small Scale ◽  
Data Logging ◽  
Short Term ◽  
Sensing Platforms

The study of the dynamic responses of plants to short-term environmental changes is becoming increasingly important in basic plant science, phenotyping, breeding, crop management, and modelling. These short-term variations are crucial in plant adaptation to new environments and, consequently, in plant fitness and productivity. Scalable, versatile, accurate, and low-cost data-logging solutions are necessary to advance these fields and complement existing sensing platforms such as high-throughput phenotyping. However, current data logging and sensing platforms do not meet the requirements to monitor these responses. Therefore, a new modular data logging platform was designed, named Gloxinia. Different sensor boards are interconnected depending upon the needs, with the potential to scale to hundreds of sensors in a distributed sensor system. To demonstrate the architecture, two sensor boards were designed—one for single-ended measurements and one for lock-in amplifier based measurements, named Sylvatica and Planalta, respectively. To evaluate the performance of the system in small setups, a small-scale trial was conducted in a growth chamber. Expected plant dynamics were successfully captured, indicating proper operation of the system. Though a large scale trial was not performed, we expect the system to scale very well to larger setups. Additionally, the platform is open-source, enabling other users to easily build upon our work and perform application-specific optimisations.

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