Particle Based Numerical Analysis of Green Water on FPSO Deck

2013 ◽  
Author(s):  
Cezar Augusto Bellezi ◽  
Liang-Yee Cheng ◽  
Kazuo Nishimoto
Keyword(s):  
Experimental Data ◽  
Numerical Analysis ◽  
Sea Water ◽  
Three Dimensional ◽  
High Amplitude ◽  
Green Water ◽  
Scale Models ◽  
Three Dimensional Models ◽  
Reduced Scale ◽  
Good Agreement

The green water phenomenon is boarding of sea water onto the deck due to high amplitude waves, which can cause several damages to the equipment on deck. In the present paper the green water phenomenon on three-dimensional models is analyzed using the Moving Particles Semi-Implicit Method (MPS), a fully lagrangian method for incompressible flow. This work is focused on the validation of the method comparing the numerical results with experimental results for green water on reduced scale models. The pressure on sensors over the deck of the models shows good agreement with experimental data.

APPLICATION OF A NEW HAMILTONIAN OF INTERACTION TO THREE-DIMENSIONAL STRUCTURES

2004 ◽  
Vol 18 (09) ◽  
pp. 1351-1368
Author(s):  
ANDREI DOLOCAN ◽  
VOICU OCTAVIAN DOLOCAN ◽  
VOICU DOLOCAN
Keyword(s):  
Experimental Data ◽  
Cohesive Energy ◽  
Noble Gases ◽  
Three Dimensional ◽  
The Other ◽  
Ionic Crystals ◽  
Coupling Constant ◽  
Good Agreement

Using a new Hamiltonian of interaction we have calculated the cohesive energy in three-dimensional structures. We have found the news dependences of this energy on the distance between the atoms. The obtained results are in a good agreement with experimental data in ionic, covalent and noble gases crystals. The coupling constant γ between the interacting field and the atoms is somewhat smaller than unity in ionic crystals and is some larger than unity in covalent and noble gases crystals. The formulae found by us are general and may be applied, also, to the other types of interactions, for example, gravitational interactions.

Dose-window dependence on Si crystal orientation in separation by implanted oxygen substrate formation

2004 ◽  
Vol 19 (12) ◽  
pp. 3607-3613 ◽  
Author(s):  
H. Iikawa ◽  
M. Nakao ◽  
K. Izumi
Keyword(s):  
Experimental Data ◽  
Numerical Analysis ◽  
Crystal Orientation ◽  
Oxygen Ion ◽  
The Difference ◽  
First Time ◽  
Good Agreement

Separation by implemented oxygen (SIMOX)(111) substrates have been formed by oxygen-ion (16O+) implantation into Si(111), showing that a so-called “dose-window” at 16O+-implantation into Si differs from Si(100) to Si(111). In SIMOX(100), an oxygen dose of 4 × 1017/cm2 into Si(100) is widely recognized as the dose-window when the acceleration energy is 180 keV. For the first time, our work shows that an oxygen dose of 5 × 1017/cm2 into Si(111) is the dose-window for the formation of SIMOX(111) substrates when the acceleration energy is 180 keV. The difference between dose-windows is caused by anisotropy of the crystal orientation during growth of the faceted buried SiO2. We also numerically analyzed the data at different oxidation velocities for each facet of the polyhedral SiO2 islands. Numerical analysis results show good agreement with the experimental data.

Numerical Analysis of the Flow Inside a Centrifugal Compressor’s Vaneless Diffuser and Volute

2001 ◽  
Author(s):  
Hooman Rezaei ◽  
Abraham Engeda ◽  
Paul Haley
Keyword(s):  
Experimental Data ◽  
Numerical Analysis ◽  
Mass Flow ◽  
Operating Conditions ◽  
Vaneless Diffuser ◽  
Flow Angle ◽  
Flow Rates ◽  
Mass Flow Rates ◽  
Minimum Medium ◽  
Good Agreement

Abstract The objective of this work was to perform numerical analysis of the flow inside a modified single stage CVHF 1280 Trane centrifugal compressor’s vaneless diffuser and volute. Gambit was utilized to read the casing geometry and generating the vaneless diffuser. An unstructured mesh was generated for the path from vaneless diffuser inlet to conic diffuser outlet. At the same time a meanline analysis was performed corresponding to speeds and mass flow rates of the experimental data in order to obtain the absolute velocity and flow angle leaving the impeller for those operating conditions. These values and experimental data were used as inlet and outlet boundary conditions for the simulations. Simulations were performed in Fluent 5.0 for three speeds of 2000, 3000 and 3497 RPM and mass flow rates of minimum, medium and maximum. Results are in good agreement with the experimental ones and present the flow structures inside the vaneless diffuser and volute.

scholarly journals NUMERICAL ANALYSIS OF SHORT AND LONG INSTRUMENTATION IN THE TREATMENT OF THORACOLUMBAR FRACTURES CONSIDERING THE LIGAMENTOUS PORTION

2019 ◽  
Vol 18 (2) ◽  
pp. 144-150
Author(s):  
André Rafael Hubner ◽  
Danilo Mourão Ribeiro ◽  
Eduardo Dassoler ◽  
Daniel Gasparin ◽  
Charles Leonardo Israel ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Thoracolumbar Spine ◽  
Three Dimensional ◽  
Maximum Tensile Stress ◽  
Thoracolumbar Fractures ◽  
Level Of Evidence ◽  
Safety Coefficient ◽  
Computed Tomography Images ◽  
Three Dimensional Models ◽  
Anterior Posterior

ABSTRACT Objective: This study aims to numerically evaluate the surgical treatment of thoracolumbar fractures, comparing the strengths between the long and short fixations using the pedicle of the fractured vertebra, taking into account the supraspinous, intertransverse, and anterior longitudinal ligaments. Methods: A numerical analysis of the techniques of long and short fixation of a thoracolumbar spine fracture was performed using computed tomography images that were converted into three-dimensional models and analyzed through the ANSYS program. The two types of treatments were analyzed considering the tensions generated in the immediate postoperative period, when the fracture has not yet been consolidated. The anterior, posterior, supraspinal and intertransverse longitudinal ligaments were added, in addition to considering different vertebral geometries. Results: Taking into account that the maximum tensile stress of the material used in the metal implant, in the case of titanium, was 960 MPa, the highest tension found in the analysis of the short instrumentation was 346.83 MPa, reaching only 36.13% of the load the material supports, being, therefore, within a safety limit. The analysis performed in the spine with long instrumentation showed the highest tension value of 229.22 MPa. Conclusions: Considering the values found and the resistance of the synthesis material used, the short and long fixation can be considered in the treatment of thoracolumbar fractures with similarity and a good safety coefficient. Level of Evidence III; Case-Control.

scholarly journals Design and analysis of flow rectifier of gas turbine flowmeter

2013 ◽  
Vol 17 (5) ◽  
pp. 1504-1507 ◽  
Author(s):  
Zhi-Fei Li ◽  
Zheng Du ◽  
Kai Zhang ◽  
Dong-Sheng Li ◽  
Zhong-Di Su ◽  
...  
Keyword(s):  
Experimental Data ◽  
Flow Field ◽  
Computational Model ◽  
Pressure Distribution ◽  
Gas Turbine ◽  
Turbulence Model ◽  
Pressure Loss ◽  
Three Dimensional ◽  
Turbine Flowmeter ◽  
Good Agreement

Three-dimensional computational model for a gas turbine flowmeter is proposed, and the finite volume based SIMPLEC method and k-? turbulence model are used to obtain the detailed information of flow field in turbine flowmeter, such as velocity and pressure distribution. Comparison between numerical results and experimental data reveals a good agreement. A rectifier with little pressure loss is optimally designed and validated numerically and experimentally.

scholarly journals Weak Localization Effect in Superconductors

1998 ◽  
Vol 12 (19) ◽  
pp. 763-773 ◽  
Author(s):  
Yong-Jihn Kim ◽  
K. J. Chang
Keyword(s):  
Experimental Data ◽  
Thin Films ◽  
Sheet Resistance ◽  
Three Dimensional ◽  
Weak Localization ◽  
Transition Temperatures ◽  
Universal Behavior ◽  
Localization Effect ◽  
Disordered Superconductors ◽  
Good Agreement

We investigate the effect of weak localization on the transition temperatures of superconductors using Anderson's time-reversed scattered-state pairs, and show that disorder weakens electron–phonon interactions. With solving the BCS T c -equation, the calculated values for T c are in good agreement with experimental data for various two- and three-dimensional disordered superconductors. We find that the critical sheet resistance for the suppression of superconductivity in thin films does not satisfy the universal behavior but depends on sample, in good agreement with experiments.

Design Methods of Volute Casings for Turbocharger Turbine Applications

1996 ◽  
Vol 210 (2) ◽  
pp. 149-156 ◽  
Author(s):  
H Chen
Keyword(s):  
Experimental Data ◽  
Potential Flow ◽  
Design Method ◽  
Three Dimensional ◽  
Design Methods ◽  
Two Dimensional ◽  
Aerodynamic Design ◽  
3D Design ◽  
Flow Equations ◽  
Good Agreement

This paper discusses aerodynamic design methods of volute casings used in turbocharger turbines. A quasi-three-dimensional (Q-3D) design method is proposed in which a group of extended two-dimensional potential flow equations and the streamline equation are numerically solved to obtain the geometry of spiral volutes. A tongue loss model, based on the turbulence wake theory, is also presented, and good agreement with experimental data is shown.

The Effect of the Carbon Epoxy Plate’s Size under Low Velocity Impact

2008 ◽  
Vol 587-588 ◽  
pp. 951-955
Author(s):  
Ana M. Amaro ◽  
Paulo N.B. Reis ◽  
Marcelo F.S.F. de Moura
Keyword(s):  
Numerical Analysis ◽  
Testing Machine ◽  
Three Dimensional ◽  
Experimental Tests ◽  
Low Velocity Impact ◽  
Rectangular Plates ◽  
Low Velocity ◽  
Velocity Impact ◽  
Impact Energies ◽  
Good Agreement

The aim of present work is to study the influence of the plate’s size on low velocity impact on carbon-fibre-reinforced epoxy laminates. Experimental tests were performed on [04,904]s laminates, using a drop weight-testing machine. Circular, square and rectangular plates were tested under low velocity impacts using a hemispherical impactor with 20 mm diameter and 3 J impact energies. The impacted plates were inspected by X-radiography. Numerical simulations were also performed considering interface finite elements compatible with three-dimensional solid elements, which allows to model delamination onset and growth between layers. The results showed that the plate’s size has influence on the delaminated area. Good agreement between experimental and numerical analysis for shape, orientation and size of the delaminations was obtained.

scholarly journals MODELING OF ELASTIC-PLASTIC DEFORMATION OF ELEMENTS OF SPATIAL STRUCTURES DURING PULSE INTERACTION WITH FLUID BASED ON THE GODUNOV'S METHOD OF INCREASED ACCURACY

2019 ◽  
Vol 81 (4) ◽  
pp. 488-499
Author(s):  
Wang Cheng ◽  
Yang Tonghui ◽  
Li Wan ◽  
Tao Li ◽  
M.H. Abuziarov ◽  
...  
Keyword(s):  
Experimental Data ◽  
Shock Waves ◽  
Elastoplastic Deformation ◽  
Three Dimensional ◽  
Numerical Results ◽  
Two Dimensional ◽  
Wave Processes ◽  
Detonation Products ◽  
Comparison Of The Results ◽  
Good Agreement

The spatial problem of internal explosive loading of an elastoplastic cylindrical container filled with water in Eulerian - Lagrangian variables using multigrid algorithms is considered. A defining system of three-dimensional equations of the dynamics of gas, fluid, and elastoplastic medium is presented. For numerical modeling, a modification of S.K. Godunov scheme of the increased accuracy for both detonation products and liquids, and elastoplastic container is used. At the moving contact boundaries “detonation products - liquid”, “liquid - deformable body”, the exact solution of the Riemann's problem is used. A time dependent model is used to describe the propagation of steady-state detonation wave through an explosive from an initiation region. In both cases, the initiation of detonation occurs at the center of the charge. Two problems have been solved: the first task for the aisymmetric position of the charge, the second for the charge shifted relative to the axis of symmetry. In the first task, the processes are two-dimensional axisymmetric in nature, in the second task, the processes are essentially three-dimensional. A comparison is made of the results of calculations of the first problem using a three-dimensional method with a solution using a previously developed two-dimensional axisymmetric method and experimental data. Good agreement is observed between the numerical results for the maximum velocities and circumferential strains obtained by various methods and experimental data. There is good agreement between the numerical results obtained by various methods and the known experimental data. Comparison of the results of solving the first and second problems shows a significant effect of the position of the charge on the wave processes in the liquid, the processes of loading the container and its elastoplastic deformation. The dynamic behavior of a gas bubble with detonation products is analyzed. A significant deviation of the bubble shape from the spherical one, caused by the action of shock waves reflected from the structure, is shown. Comparison of the results of solving the first and second problems showed a significant effect of the charge position on wave processes in a liquid, the processes of loading a container and its elastoplastic deformation. In particular, in the second problem, shock waves of higher amplitude are observed in the liquid when reflected from the walls of the container.

Effect of Droplet Starting Conditions on the Spray Dispersion Resulting From a Swirl Cup Injector

2021 ◽  
Author(s):  
Niklas Bürkle ◽  
Simon Holz ◽  
Enrico Bärow ◽  
Rainer Koch ◽  
Hans-Jörg Bauer
Keyword(s):  
Experimental Data ◽  
Droplet Diameter ◽  
Three Dimensional ◽  
Fuel Injector ◽  
Viable Option ◽  
Lagrange Method ◽  
Precessing Vortex Core ◽  
Starting Conditions ◽  
Good Agreement ◽  
Modelling Approach

Abstract In this work a numerical investigation of the sensitivities of the spray dispersion to different droplet starting parameters in a realistic three-dimensional fuel injector geometry is presented. The simulations are carried out using an Euler-Lagrange method. An extended version of the primary atomization model PAMELA [1,2] is used to predict the droplet diameter and to set the droplet starting conditions. Spray characteristics are compared to experimental data [3]. Thereby, a strong influence of the initial droplet velocities, the recirculation zone, the precessing vortex core as well as the turbulence modelling approach on the spray dispersion was identified. Droplet starting conditions which provide good agreement to the experimental data are determined. The study demonstrates that the presented approach is a viable option to predict the spray dispersion in combustors. Moreover, valuable insights on necessary improvements for modeling primary atomization are given.

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