Full-scale validation of FE models for geometrically imperfect flange connections

The biological reactions during the settling and decant periods of Sequencing Batch Reactors (SBRs) are generally ignored as they are not easily measured or described by modelling approaches. However, important processes are taking place, and in particular when the influent is fed into the bottom of the reactor at the same time (one of the main features of the UniFed process), the inclusion of these stages is crucial for accurate process predictions. Due to the vertical stratification of both liquid and solid components, a one-dimensional hydraulic model is combined with a modified ASM 2d biological model to allow the prediction of settling velocity, sludge concentration, soluble components and biological processes during the non-mixed periods of the SBR. The model is calibrated on a full-scale UniFed SBR system with tracer breakthrough tests, depth profiles of particulate and soluble compounds and measurements of the key components during the mixed aerobic period. This model is then validated against results from an independent experimental period with considerably different operating parameters. In both cases, the model is able to accurately predict the stratification and most of the biological reactions occurring in the sludge blanket and the supernatant during the non-mixed periods. Together with a correct description of the mixed aerobic period, a good prediction of the overall SBR performance can be achieved.

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Development and Qualification of Pipeline Welding Procedures for Strain Based Design

Volume 4: Materials Technology; Ocean Engineering ◽

10.1115/omae2007-29581 ◽

2007 ◽

Cited By ~ 1

Author(s):

Martin W. Hukle ◽

Dan B. Lillig ◽

Brian D. Newbury ◽

John Dwyer ◽

Agnes Marie Horn

Keyword(s):

Large Scale ◽

Scale Validation ◽

Gas Metal Arc Welding ◽

Full Scale ◽

Pipe Material ◽

Metal Arc Welding ◽

Offshore Pipeline ◽

Pipeline Welding ◽

Girth Welds ◽

Procedure Development

This paper reviews the specific testing methodologies implemented for the qualification of mechanized pulsed gas metal arc welding (PGMAW) procedures for strain based design applications. The qualified welding procedures were used during recent construction of an offshore pipeline subject to potential ice scour with an initial design target of 4% tensile strain capacity. This paper addresses the integrated development of linepipe specifications, large scale validation testing, weld procedure development, and finally, the verification of robustness through full scale pressurized testing of actual girth welds on project pipe material. The qualification sequence, from linepipe specification development through final full scale girth weld proof test is described.

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Measurement and Modeling of the Motions of a High-Speed Catamaran in Waves

Volume 4: Ocean Engineering; Ocean Renewable Energy; Ocean Space Utilization, Parts A and B ◽

10.1115/omae2009-79810 ◽

2009 ◽

Cited By ~ 3

Author(s):

T. C. Fu ◽

A. M. Fullerton ◽

E. Terrill ◽

W. Faller ◽

G. Lada ◽

...

Keyword(s):

High Speed ◽

Scale Validation ◽

Full Scale ◽

Ship Motions ◽

Naval Research ◽

Vertical Acceleration ◽

Incoming Wave ◽

Validation Data ◽

Rough Water ◽

Ship Speed

Wetdeck slamming can be defined as a large vertical acceleration event that occurs when ship motions cause an impact between the cross deck and the ocean’s surface. The use of Computational Fluid Dynamics (CFD) and other simulation tools to accurately predict wetdeck slamming loads and ship motions has become the objective of a number of efforts (Hess, et al, 2007; Lin, et al, 2007; Faller et al, 2008; for example). The Sea Fighter, FSF-1, is a high-speed research vessel developed by the U.S. Office of Naval Research (ONR). Christened in 2005, she is an aluminum catamaran propelled by four steerable water jets capable of speeds up to 50 knots. In 2006, Sea Fighter underwent a series of rough water trials to assess its operational profile in high sea states (Fu, et. al., 2007). Along with this assessment, ONR sponsored an effort to obtain full-scale qualitative and quantitative wave slamming and ship motion data. One of these rough water trials took place 18–20 April 2006 as the ship transited from Esquimalt, British Columbia, Canada to San Diego, California, USA. During this trial, the significant wave height ranged from 1.5 to 2.7 m and the ship speed ranged from 20 to 40 knots. This paper describes the results of the effort to characterize the Sea Fighter’s motion in waves. To provide suitable full-scale validation data, the incoming ambient waves had to be characterized. A Light Detecting and Ranging, (LiDAR) system, an array of ultrasonic distance sensors, and several video cameras were used to characterize the incoming wave field. In addition, three fiber optic gyro motion units were deployed to record ship motions. Additionally, a GPS unit was utilized to measure ship speed, pitch, roll, and heading. Several slam and near slam events are discussed over the range of ship’s speed, heading, and sea states tested. Similarities and differences between these events are also noted. Additionally, this data was used to develop a simulation of the Sea Fighter’s motion in waves similar to previous work done utilizing model test data (Hess, et al, 2007; Faller et al, 2008).

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Full-Scale Validation of a Vessel’s Station-Keeping Capability With DynCap

Volume 9: Offshore Geotechnics; Torgeir Moan Honoring Symposium ◽

10.1115/omae2017-62666 ◽

2017 ◽

Cited By ~ 1

Author(s):

Luca Pivano ◽

Dong Nguyen ◽

Øyvind Smøgeli

Keyword(s):

Time Domain ◽

Scale Validation ◽

Operational Risk ◽

Full Scale ◽

Management Tools ◽

Worst Case ◽

Operational Risks ◽

Steady Growth ◽

Transient Period ◽

Key Aspects

With the steady growth of the number of Dynamic Positioning (DP) vessels, increasingly complex designs and operations, and a decreasing number of experienced DP operators, effective operational risk management tools are key for safer and more efficient operations. One of the key aspects when looking at the operational risks is the estimation of the vessel position and heading after the worst case single failure and in the transient period after the failure has occurred. The aim of this paper is to provide insight about the use of comprehensive dynamic operability analyses performed by time-domain simulations for understanding the vessel performance and limitations, in turn providing valuable and reliable input to operational risk assessment and planning. This paper presents also a comparison with results from full-scale trials.

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High-Frequency Model of Magnetic Rings for Simulation of VFTO Damping in Gas-Insulated Switchgear With Full-Scale Validation

IEEE Transactions on Power Delivery ◽

10.1109/tpwrd.2015.2417675 ◽

2015 ◽

Vol 30 (5) ◽

pp. 2331-2338 ◽

Cited By ~ 8

Author(s):

Marcin Szewczyk ◽

Jaroslaw Pawlowski ◽

Kamil Kutorasinski ◽

Wojciech Piasecki ◽

Marek Florkowski ◽

...

Keyword(s):

High Frequency ◽

Scale Validation ◽

Full Scale ◽

Frequency Model ◽

Gas Insulated Switchgear ◽

Magnetic Rings

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A New Method for Seismically Safe Managing of Seismotectonic Deformations in Fault Zones

Springer Tracts in Mechanical Engineering - Multiscale Biomechanics and Tribology of Inorganic and Organic Systems ◽

10.1007/978-3-030-60124-9_3 ◽

2020 ◽

pp. 45-66

Author(s):

Valery V. Ruzhich ◽

Evgeny V. Shilko

Keyword(s):

Large Scale ◽

Scale Validation ◽

Fault Zones ◽

Full Scale ◽

Coseismic Slip ◽

Stick Slip ◽

Slip Regime ◽

Deep Wells ◽

Seismic Vibrations ◽

Large Scale Tests

AbstractThe authors outline the results of long-term interdisciplinary research aimed at identifying the possibility and the methods of controlling tangential displacements in seismically dangerous faults to reduce the seismic risk of potential earthquakes. The studies include full-scale physical and numerical modeling of P-T conditions in the earth’s crust contributing to the initiation of displacement in the stick-slip regime and associated seismic radiation. A cooperation of specialists in physical mesomechanics, seismogeology, geomechanics, and tribology made it possible to combine and generalize data on the mechanisms for the formation of the sources of dangerous earthquakes in the highly stressed segments of faults. We consider the prospect of man-caused actions on the deep horizons of fault zones using powerful shocks or vibrations in combination with injecting aqueous solutions through deep wells to manage the slip mode. We show that such actions contribute to a decrease in the coseismic slip velocity in the fault zone, and, therefore, cause a decrease in the amplitude and energy of seismic vibrations. In conclusion, we substantiate the efficiency of the use of combined impacts on potentially seismically hazardous segments of fault zones identified in the medium-term seismic prognosis. Finally, we discuss the importance of the full-scale validation of the proposed approach to managing the displacement regime in highly-stressed segments of fault zones. Validation should be based on large-scale tests involving advanced technologies for drilling deep multidirectional wells, injection of complex fluids, and localized vibrational or pulse impacts on deep horizons.

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