Impact Simulation of Liquid-Filled Containers Including Fluid-Structure Interaction—Part 2: Experimental Verification

1993 ◽  
Vol 115 (1) ◽  
pp. 73-79
Author(s):  
R. G. Sauve´ ◽  
G. D. Morandin ◽  
E. Nadeau
Keyword(s):  
Fluid Model ◽  
Numerical Technique ◽  
Liquid Radioactive Waste ◽  
Three Dimensional ◽  
Volumetric Strain ◽  
Computer Code ◽  
Compressible Medium ◽  
Hydrodynamic Effect ◽  
Inviscid Fluid ◽  
Element Discretization

In a number of applications, the hydrodynamic effect of a fluid must be included in the structural evaluation of liquid-filled vessels undergoing transient loading. Prime examples are liquid radioactive waste transportation packages. These packages must demonstrate the ability to withstand severe accidental impact scenarios. A hydrodynamic model of the fluid is developed using a finite element discretization of the momentum equations for a three-dimensional continuum. An inviscid fluid model with an isotropic stress state is considered. A barotropic equation of state, relating volumetric strain to pressure, is used to characterize the fluid behavior. The formulation considers the continuum as a compressible medium only, so that no tension fields are permitted. The numerical technique is incorporated into the existing general-purpose three-dimensional structural computer code H3DMAP. Part 1 of the paper describes the theory and implementation along with comparisons with classical theory. Part 2 describes the experimental validation of the theoretical approach. Excellent correlation between predicted and experimental results is obtained.

Impact Simulation of Liquid-Filled Containers Including Fluid-Structure Interaction—Part 1: Theory

1993 ◽  
Vol 115 (1) ◽  
pp. 68-72 ◽  
Author(s):  
R. G. Sauve´ ◽  
G. D. Morandin ◽  
E. Nadeau
Keyword(s):  
Fluid Model ◽  
Numerical Technique ◽  
Liquid Radioactive Waste ◽  
Three Dimensional ◽  
Volumetric Strain ◽  
Computer Code ◽  
Compressible Medium ◽  
Hydrodynamic Effect ◽  
Inviscid Fluid ◽  
Element Discretization

In a number of applications, the hydrodynamic effect of a fluid must be included in the structural evaluation of liquid-filled vessels undergoing transient loading. Prime examples are liquid radioactive waste transportation packages. These packages must demonstrate the ability to withstand severe accidental impact scenarios. A hydrodynamic model of the fluid is developed using a finite element discretization of the momentum equations for a three-dimensional continuum. An inviscid fluid model with an isotropic stress state is considered. A barotropic equation of state, relating volumetric strain to pressure, is used to characterize the fluid behavior. The formulation considers the continuum as a compressible medium only, so that no tension fields are permitted. The numerical technique is incorporated into the existing general-purpose three-dimensional structural computer code H3DMAP. Part 1 of the paper describes the theory and implementation along with comparisons with classical theory. Part 2 describes the experimental validation of the theoretical approach. Excellent correlation between predicted and experimental results is obtained.

Boundary-Integral Computation of Hydrodynamic Interactions Between a Three-Dimensional Body and an Infinitely Long Cylinder

1993 ◽  
Vol 37 (04) ◽  
pp. 281-297
Author(s):  
Zhi Guo ◽  
Allen T. Chwang
Keyword(s):  
Circular Cylinder ◽  
Numerical Technique ◽  
Three Dimensional ◽  
Boundary Integral ◽  
Boundary Integral Method ◽  
Hydrodynamic Interactions ◽  
Inviscid Fluid ◽  
Body Of Revolution ◽  
Infinite Region ◽  
Added Masses

Hydrodynamic interactions between a three-dimensional body of revolution and an infinitely long circular cylinder in an inviscid fluid are studied numerically by the boundary-integral method. The added-mass coefficients and their derivatives are computed in terms of the solutions of four integral equations of the second kind. A numerical technique based on variable transformations is developed to evaluate integrations over steep peaks. Integrations over the cylindrical surface are properly computed by mapping the infinite region onto a finite region and regularizing the ill-behaved kernels with sharp peaks. The discrete added masses and their derivatives are fitted by the least-squares approximation on the basis of Legendre polynomials. As a practical example, the moving trajectories of a sphere conveyed by a uniform flow around a fixed circular cylinder are computed and presented.

scholarly journals Simulation and measurement of air quality in the traffic congestion area

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Shin Yu ◽  
Chang Tang Chang ◽  
Chih Ming Ma
Keyword(s):  
Air Quality ◽  
Traffic Congestion ◽  
Traffic Management ◽  
Reference Model ◽  
Dispersion Model ◽  
Fluid Model ◽  
Three Dimensional ◽  
Vehicle Speed ◽  
Management Plans ◽  
Dimensional Distribution

AbstractThe traffic congestion in the Hsuehshan tunnel and at the Toucheng interchange has led to traffic-related air pollution with increasing concern. To ensure the authenticity of our simulation, the concentration of the last 150 m in Hsuehshan tunnel was simulated using the computational fluid dynamics fluid model. The air quality at the Toucheng interchange along a 2 km length highway was simulated using the California Line Source Dispersion Model. The differences in air quality between rush hours and normal traffic conditions were also investigated. An unmanned aerial vehicle (UAV) with installed PM2.5 sensors was developed to obtain the three-dimensional distribution of pollutants. On different roads, during the weekend, the concentrations of pollutants such as SOx, CO, NO, and PM2.5 were observed to be in the range of 0.003–0.008, 7.5–15, 1.5–2.5 ppm, and 40–80 μg m− 3, respectively. On weekdays, the vehicle speed and the natural wind were 60 km h− 1 and 2.0 m s− 1, respectively. On weekdays, the SOx, CO, NO, and PM2.5 concentrations were found to be in the range of 0.002–0.003, 3–9, 0.7–1.8 ppm, and 35–50 μg m− 3, respectively. The UAV was used to verify that the PM2.5 concentrations of vertical changes at heights of 9.0, 7.0, 5.0, and 3.0 m were 45–48, 30–35, 25–30, and 50–52 μg m− 3, respectively. In addition, the predicted PM2.5 concentrations were 40–45, 25–30, 45–48, and 45–50 μg m− 3 on weekdays. These results provide a reference model for environmental impact assessments of long tunnels and traffic jam-prone areas. These models and data are useful for transportation planners in the context of creating traffic management plans.

Mechanical behaviour of powders using a medium pressure flexible boundary cubical triaxial tester

2003 ◽  
Vol 217 (3) ◽  
pp. 233-241 ◽  
Author(s):  
F Li ◽  
V M Puri
Keyword(s):  
Shear Modulus ◽  
Mechanical Behaviour ◽  
Triaxial Compression ◽  
Three Dimensional ◽  
Volumetric Strain ◽  
Confining Pressure ◽  
Alumina Powder ◽  
Medium Pressure ◽  
Mean Pressure ◽  
Confining Pressures

A medium pressure (<21 MPa) flexible boundary cubical triaxial tester was designed to measure the true three-dimensional response of powders. In this study, compression behaviour and strength of a microcrystalline cellulose powder (Avicel® PH102), a spray-dried alumina powder (A16SG), and a fluid-bed-granulated silicon nitride based powder (KY3500) were measured. To characterize the mechanical behaviour, three types of triaxial stress paths, that is, the hydrostatic triaxial compression (HTC), the conventional triaxial compression (CTC), and the constant mean pressure triaxial compression (CMPTC) tests were performed. The HTC test measured the volumetric response of the test powders under isostatic pressure from 0 to 13.79MPa, during which the three powders underwent a maximum volumetric strain of 40.8 per cent for Avicel® PH102, 30.5 per cent for A16SG, and 33.0 per cent for KY3500. The bulk modulus values increased 6.4-fold from 57 to 367MPa for Avicel® PH102, 3.7-fold from 174 to 637 MPa for A16SG, and 8.1-fold from 74 to 597MPa for KY3500, when the isotropic stress increased from 0.69 to 13.79 MPa. The CTC and CMPTC tests measured the shear response of the three powders. From 0.035 to 3.45MPa confining pressure, the shear modulus increased 28.7-fold from 1.6 to 45.9MPa for Avicel® PH102, 35-fold from 1.7 to 60.5MPa for A16SG, and 28.5-fold from 1.5 to 42.8MPa for KY3500. In addition, the failure stresses of the three powders increased from 0.129 to 4.41 MPa for Avicel® PH102, 0.082 to 3.62 MPa for A16SG, and 0.090 to 4.66MPa for KY3500, respectively, when consolidation pressure increased from 0.035 to 3.45MPa. In addition, the shear modulus and failure stress values determined from the CTC test at 2.07, 2.76, and 3.45MPa confining pressures are consistently greater than those from the CMPTC test at the same constant mean pressures. This observation demonstrates the influence of stress paths on material properties. The CTT is a useful tool for characterizing the three-dimensional response of powders and powder mixtures.

scholarly journals Computation of Three-Dimensional, Rotational Flow Through Turbomachinery Blade Rows for Improved Aerodynamic Design Studies

1986 ◽  
Author(s):  
S. V. Subramanian ◽  
R. Bozzola ◽  
Louis A. Povinelli
Keyword(s):  
Three Dimensional ◽  
Maximum Flow ◽  
Cost Effective ◽  
Computer Code ◽  
Integration Scheme ◽  
Aerodynamic Design ◽  
Design Studies ◽  
Flow Equations ◽  
Transonic Compressor ◽  
Numerical Predictions

The performance of a three dimensional computer code developed for predicting the flowfield in stationary and rotating turbomachinery blade rows is described in this study. The four stage Runge-Kutta numerical integration scheme is used for solving the governing flow equations and yields solution to the full, three dimensional, unsteady Euler equations in cylindrical coordinates. This method is fully explicit and uses the finite volume, time marching procedure. In order to demonstrate the accuracy and efficiency of the code, steady solutions were obtained for several cascade geometries under widely varying flow conditions. Computed flowfield results are presented for a fully subsonic turbine stator and a low aspect ratio, transonic compressor rotor blade under maximum flow and peak efficiency design conditions. Comparisons with Laser Anemometer measurements and other numerical predictions are also provided to illustrate that the present method predicts important flow features with good accuracy and can be used for cost effective aerodynamic design studies.

scholarly journals A three-dimensional steady state thermal fluid model of jumbo ingot casting during electron beam re-melting of Ti–6Al–4V

2014 ◽  
Vol 38 (14) ◽  
pp. 3607-3623 ◽  
Author(s):  
X. Zhao ◽  
C. Reilly ◽  
L. Yao ◽  
D.M. Maijer ◽  
S.L. Cockcroft ◽  
...  
Keyword(s):  
Electron Beam ◽  
Steady State ◽  
Fluid Model ◽  
Three Dimensional ◽  
Ingot Casting

Integrity Assessment of Damaged Flexible Pipe Cross-Sections

2014 ◽  
Author(s):  
Guomin Ji ◽  
Bernt J. Leira ◽  
Svein Sævik ◽  
Frank Klæbo ◽  
Gunnar Axelsson ◽  
...  
Keyword(s):  
Cross Sections ◽  
Three Dimensional ◽  
Element Model ◽  
Computer Code ◽  
Flexible Pipe ◽  
Dynamic Stresses ◽  
Integrity Assessment ◽  
Residual Capacity ◽  
Nonlinear Finite Element Model

This paper presents results from a case study performed to evaluate the residual capacity of a 6″ flexible pipe when exposed to corrosion damages in the tensile armour. A three-dimensional nonlinear finite element model was developed using the computer code MARC to evaluate the increase in mean and dynamic stresses for a given number of damaged inner tensile armor wires. The study also includes the effect of these damages with respect to the associated stresses in the pressure spiral. Furthermore, the implications of a sequence of wire failures with respect to the accumulated time until cross-section failure in a probabilistic sense are addressed.

GEOPOLIS software tools – Groundwater flow modeling at deep repository of liquid radioactive waste at Severny test site

2021 ◽  
pp. 91-97
Author(s):  
V. V. Suskin ◽  
A. V. Rastorguev ◽  
I. V. Kapyrin
Keyword(s):  
Groundwater Flow ◽  
Flow Model ◽  
Liquid Radioactive Waste ◽  
Three Dimensional ◽  
Test Site ◽  
Geological Structure ◽  
Groundwater Flow Model ◽  
Flow Modeling ◽  
Three Dimensional Model ◽  
Groundwater Flow Modeling

This article discusses a three-dimensional groundwater flow model of a deep disposal facility at Severny test site. The three-dimensional model is a part of the certified software GEOPOLIS, based on the hydrogeological code GeRa (Geomigration of Radionuclides) serving as the calculation engine. This study describes the hydrogeological patterning of the groundwater flow model, as well as the results of calibration and verification of the model water heads with respect to the data of monitoring for more than 40 years of the deep repository exploitation. The article begins with a brief overview of the previously developed hydrogeological models of this object and continues with a description of the geological structure of the territory, and with a substantiation of the boundaries and parameters of the model. The results of groundwater flow modeling, model calibration, verification and estimation of discrepancy between the model results and monitoring data are shown. The comparison of the modeled and observed water heads in the stationary conditions (before the start of injection) and during operation of the deep repository allows making conclusion on the quality of calibration.

Preliminary results of numerical simulation of submarine landslide-generated waves

2021 ◽  
Author(s):  
Ramtin Sabeti ◽  
Mohammad Heidarzadeh
Keyword(s):  
Numerical Simulation ◽  
Numerical Modelling ◽  
Numerical Solutions ◽  
Numerical Technique ◽  
Source Region ◽  
Three Dimensional ◽  
Terminal Velocity ◽  
Sensitivity Analyses ◽  
Physical Experiments ◽  
Set Up

&lt;p&gt;Landslide-generated waves have been major threats to coastal areas and have led to destruction and casualties. Their importance is undisputed, most recently demonstrated by the 2018 Anak Krakatau tsunami, causing several hundred fatalities. The accurate prediction of the maximum initial amplitude of landslide waves (&lt;em&gt;&amp;#951;&lt;sub&gt;max&lt;/sub&gt;&lt;/em&gt;) around the source region is a vital hazard indicator for coastal impact assessment. Laboratory experiments, analytical solutions and numerical modelling are three major methods to investigate the (&lt;em&gt;&amp;#951;&lt;sub&gt;max&lt;/sub&gt;&lt;/em&gt;). However, the numerical modelling approach provides a more flexible and cost- and time-efficient tool. This research presents a numerical simulation of tsunamis due to rigid landslides with consideration of submerged conditions. In particular, this simulation focuses on studying the effect of landslide parameters on &lt;em&gt;&amp;#951;&lt;sub&gt;max&lt;/sub&gt;.&lt;/em&gt; Results of simulations are compared with our conducted physical experiments at the Brunel University London (UK) to validate the numerical model.&lt;/p&gt;&lt;p&gt;We employ the fully three-dimensional computational fluid dynamics package, FLOW-3D Hydro for modelling the landslide-generated waves. This software benefit from the Volume of Fluid Method (VOF) as the numerical technique for tracking and locating the free surface. The geometry of the simulation is set up according to the wave tank of physical experiments (i.e. 0.26 m wide, 0.50 m deep and 4.0 m). In order to calibrate the simulation model based on the laboratory measurements, the friction coefficient between solid block and incline is changed to 0.41; likewise, the terminal velocity of the landslide is set to 0.87 m/s. Good agreement between the numerical solutions and the experimental results is found. Sensitivity analyses of landslide parameters (e.g. slide volume, water depth, etc.) on &lt;em&gt;&amp;#951;&lt;sub&gt;max &lt;/sub&gt;&lt;/em&gt;are performed. Dimensionless parameters are employed to study the sensitivity of the initial landslide waves to various landslide parameters.&lt;/p&gt;

Nonlinear structures: soliton, shocklike and explosive waves in quantum semiconductor plasma

2021 ◽  
Author(s):  
Haifa Al-Yousef
Keyword(s):  
Analytical Procedure ◽  
Integration Method ◽  
Fluid Model ◽  
Three Dimensional ◽  
Semiconductor Plasma ◽  
Direct Integration Method ◽  
Solution Methods ◽  
Gradient Forces ◽  
Quantum Semiconductor ◽  
Nonlinear Solutions

Abstract The properties and conditions for the appearance of some nonlinear waves in a three-dimensional semiconductor plasma are discussed, by studying the described plasma fluid system with quantum gradient forces and degraded pressures. Our analytical procedure is built on the reductive perturbation theory to obtain the Kadomtsev-Petvashvili equation for the fluid model and solving it using the direct integration method and the Bäcklund transform. Through different solution methods we got different nonlinear solutions describing different pulse profiles such as soliton, kink and explosive pulses. This model can be used to identify the potential disturbances in a semiconductor plasma.

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