Flow over a containment dyke

1978 ◽  
Vol 87 (1) ◽  
pp. 179-192 ◽  
Author(s):  
H. P. Greenspan ◽  
R. E. Young
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Theoretical Analysis ◽  
Fluid Motion ◽  
Strong Shock ◽  
Safety Barrier ◽  
Large Tank ◽  
The Impact ◽  
Good Agreement

The wall of a large tank or reservoir breaks, sending fluid against a secondary containment dyke. The impact of the surging fluid against the safety barrier is studied. The results of theoretical analysis and numerical simulation (for vertical dykes) are in good agreement with experimental data concerning overflow and total spillage as well as the fluid motion after collision, including the development and formation of a strong shock. The dependence of spillage on the inclination of the dyke is also determined by experiment.

scholarly journals Formation of Lunar Glassy Spherules: A Dynamical Model

1972 ◽  
Vol 47 ◽  
pp. 180-184 ◽  
Author(s):  
A. Carusi ◽  
A. Coradini ◽  
M. Fulchignoni ◽  
G. Magni
Keyword(s):  
Experimental Data ◽  
Lunar Surface ◽  
Strong Shock ◽  
Dynamical Model ◽  
Glassy Material ◽  
Spherical Drop ◽  
Lunar Dust ◽  
The Impact ◽  
Strong Shock Waves ◽  
Good Agreement

Glassy spherules ranging from 200 μ to 62 μ in size have been separated from lunar dust samples No. 12001.73, 12057.60, 12070.37. Most of them are regular in size (spherical, ellipsoidic, dumbbell, teardrop, etc.); some are irregularly shaped.A tentative dynamical model of the evolution of a rotating melted spherical drop of homogeneous glassy material has been built in order to explain the observed forms. We suppose such fluid to be originated from the impact of meteoroids on the lunar surface. The energy balance between the projectile (meteoroid) and the target (lunar surface) has been calculated supposing that the impact gives rise to strong shock waves in both bodies.Equations of the model have been solved numerically and a good agreement between these results and the experimental data regarding small spherules has been obtained.

The penetration and ricochet of ogive-nosed rigid projectiles obliquely impacting metallic targets

2021 ◽  
pp. 204141962110377
Author(s):  
Yaniv Vayig ◽  
Zvi Rosenberg
Keyword(s):  
Experimental Data ◽  
Numerical Simulations ◽  
Dynamic Pressure ◽  
Oblique Impacts ◽  
Simulation Results ◽  
The Impact ◽  
Penetration Depths ◽  
Resistance To Penetration ◽  
Good Agreement

A large number of 3D numerical simulations were performed in order to follow the trajectory changes of rigid CRH3 ogive-nosed projectiles, impacting semi-infinite metallic targets at various obliquities. These trajectory changes are shown to be related to the threshold ricochet angles of the projectile/target pairs. These threshold angles are the impact obliquities where the projectiles end up moving in a path parallel to the target’s face. They were found to depend on a non-dimensional entity which is equal to the ratio between the target’s resistance to penetration and the dynamic pressure exerted by the projectile upon impact. Good agreement was obtained by comparing simulation results for these trajectory changes with experimental data from several published works. In addition, numerically-based relations were derived for the penetration depths of these ogive-nosed projectiles at oblique impacts, which are shown to agree with the simulation results.

Dispersion of Twin Inclined Fume Jets of a Variable Height within a CrossFlow

2011 ◽  
Vol 312-315 ◽  
pp. 929-934 ◽  
Author(s):  
Amina Radhouane ◽  
Nejla Mahjoub Said ◽  
Hatem Mhiri ◽  
Georges Le Palec ◽  
Philippe Bournot
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Finite Volume Method ◽  
Single Particle ◽  
Mass Fraction ◽  
Uniform Grid ◽  
Grid System ◽  
Dispersion Process ◽  
Volume Method ◽  
The Impact

Twin elliptic inclined tandem jets are emitted within an oncoming cooler crossflow. The jets contain a non reactive fume whose dispersion is tracked all over the surrounding domain. Such a configuration may be found in chimney stacks, ships’ chimneys, etc. We propose to evaluate in the present paper the impact of the jets’ height on the resulting dispersion process. To reach this goal, a numerical simulation of a double jet model of variable height is carried out by means of the finite volume method together with a non uniform grid system. The model, validated by previous experimental data, allowed the tracking of the emitted fume by studying the evolution of a single particle contained within this fume, the Carbone dioxide (CO2) mass fraction. This is possible thanks to the assumption of handling a non reactive fume, which is adopted only to simplify the calculations. The CO2 mass fraction was mainly tracked between the emitting nozzles, in a try to find out the changes brought by the extension of the emitting jet nozzles on the flow trapped between them.

scholarly journals Numerical Simulation of Rotor in Hover and Forward Flight

2018 ◽  
Vol 179 ◽  
pp. 03011
Author(s):  
Qinghe Zhao
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Flow Field ◽  
Moving Grid ◽  
Steady State Flow ◽  
Forward Flight ◽  
Numerical Simulation Result ◽  
Structured Grid ◽  
Pressure Distributions ◽  
Good Agreement

The flow around rotor is numerical simulated in hover and forward flight based on multi-structured grid. In hover the flow field can be transformed into a steady-state flow field in the rotating coordinate system. The experimental data of Caradonna and Tung rotor is used to verify the numerical simulation result. The numerical results compare well with the experimental data for both non-lifting and lifting cases. Non-lifting forward flight is simulated and the prediction capabilities have been validated through the ONERA two-blade rotor. The pressure distributions of different positions under different azimuth angles are compared, which is in good agreement with the experimental data. There is unsteady shock wave when forward flight. Dual-time method is used to obtain unsteady flow field with rigid moving grid in the inertial system.

scholarly journals New test of the dynamic theory of neutron diffraction by a moving grating

2018 ◽  
Vol 177 ◽  
pp. 03005
Author(s):  
Maxim Zakharov ◽  
Alexander Frank ◽  
German Kulin ◽  
Semyon Goryunov
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Neutron Diffraction ◽  
Dynamic Theory ◽  
Time Of Flight ◽  
Dynamical Theory ◽  
Zero Order ◽  
Significant Suppression ◽  
Theoretical Predictions ◽  
Good Agreement

Recently, multiwave dynamical theory of neutron diffraction by a moving grating was developed. The theory predicts that at a certain height of the grating profile a significant suppression of the zero-order diffraction may occur. The experiment to confirm predictions of this theory was performed. The resulting diffracted UCNs spectra were measured using time-of-flight Fourier diffractometer. The experimental data were compared with the results of numerical simulation and were found in a good agreement with theoretical predictions.

Numerical Simulation of the Viscous Flow for the Supersonic Jet Element

2011 ◽  
Vol 189-193 ◽  
pp. 2362-2365
Author(s):  
Yong Yu ◽  
Guo Qing Zhang ◽  
Fei Wang
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Unsteady Flow ◽  
Viscous Flow ◽  
Steady Flow ◽  
Supersonic Jet ◽  
Calculated Data ◽  
Numerical Precision ◽  
Good Agreement

The viscous flow of the supersonic jet element was simulated numerically based on CFD technology, and many tests have been done to verify the numerical precision. The results show that the calculated data are good agreement with the experimental data. So the numerical simulation of the viscous flow for the supersonic jet element is accurate and reliable, and it can be applied to investigate the steady flow and unsteady flow in supersonic jet element.

Theoretical Analysis and Numerical Simulation on the Hydraulic Expansion of Double-Layered Tubes

2008 ◽  
Author(s):  
Fujun Liu ◽  
Jinyang Zheng ◽  
Shoubao Ding ◽  
Xiaolian Guo
Keyword(s):  
Numerical Simulation ◽  
Stress Distribution ◽  
Theoretical Analysis ◽  
Suitable Condition ◽  
Stress And Strain ◽  
Maximum Relative Error ◽  
Hoop Strain ◽  
Whole Process ◽  
Good Agreement

The quality of hydro-expanded double-layered tubes depends on the hydro-expanding pressure. Therefore, it is very important to determine the range of the hydro-expanding pressure accurately during the fabrication of double-layer tubes. According to theories of elasticity and plasticity, the responses of double-layered tubes subjected to five kinds of cases were analyzed during the hydro-expanding process. And the stress and strain for inner and outer tubes of double-layered tubes were discussed. By using the relation of deformed compatibility of hoop strain, suitable condition of hydraulic expansion and variable range of hydro-expanding pressure were obtained, and the calculating formulas between the hydro-expanding pressure and residual contact pressure was derived. Use the non-linear FEA MSC.patran/marc code to simulate the deformation and stress distribution, the whole process of hydraulic expansion was numerically investigated, in which the nonlinearities of the material, geometry and contact were all taken into account. The results show that the range of the hydro-expanding pressure from the numerical simulation is in good agreement with those from theoretical calculation with a maximum relative error of 6.52%. The investigation on the hydraulic expansion of double-layered tubes may guide the engineering design and provide references for further research.

scholarly journals Direct Numerical Simulation of separated turbulent flow in axisymmetric diffuser

2021 ◽  
Vol 2103 (1) ◽  
pp. 012214
Author(s):  
A S Stabnikov ◽  
D K Kolmogorov ◽  
A V Garbaruk ◽  
F R Menter
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Direct Numerical Simulation ◽  
Turbulent Flow ◽  
Turbulence Model ◽  
Eddy Viscosity ◽  
Separated Flow ◽  
Model Improvement ◽  
Good Agreement

Abstract Direct numerical simulation (DNS) of the separated flow in axisymmetric CS0 diffuser is conducted. The obtained results are in a good agreement with experimental data of Driver and substantially supplement them. Along with other data, eddy viscosity extracted from performed DNS could be used for RANS turbulence model improvement.

scholarly journals Исследование влияния размеров образцов на скорость деформации при определении прочностных динамических характеристик материала

2019 ◽  
Vol 89 (4) ◽  
pp. 567
Author(s):  
А.Д. Евстифеев ◽  
Г.А. Волков ◽  
А.А. Чеврычкина ◽  
Ю.В. Петров
Keyword(s):  
Experimental Data ◽  
Theoretical Analysis ◽  
High Strain ◽  
Acrylonitrile Butadiene Styrene ◽  
3D Printer ◽  
Dynamic Tension ◽  
Drop Hammer ◽  
Tension Experiments ◽  
Good Agreement ◽  
Butadiene Styrene

AbstractTest results are presented for an additive material prepared of acrylonitrile-butadiene-styrene on a 3D printer. Dynamic tension experiments have been carried out using a tower-type drop hammer with an accelerator. Data obtained from different specimens demonstrate that high-strain-rate tensile experiments are feasible if the working part of the specimen is decreased. A theoretical analysis of test data using the incubation time criterion has been performed, and it has been found that analytical results are in good agreement with experimental data.

Numerical Simulation of Twin-Parachute Inflation Process for Aircraft Ejection Escape

2020 ◽  
Author(s):  
Liwu Wang ◽  
Mingzhang Tang ◽  
Sijun Zhang
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Numerical Model ◽  
Physical Models ◽  
The Other ◽  
Arbitrary Lagrangian Eulerian ◽  
Safe Distance ◽  
Structure Interaction ◽  
Parachute Inflation ◽  
Good Agreement

Abstract In order to study the safe distance between twin-parachute during their inflation process for fighter ejection escape, the fighter was equipped with two canopies and two seats, two types of parachute were used to numerically simulate their inflation process, respectively. One of them is C-9, the other a slot-parachute (S-P). Their physical models were built, then the meshes inside and around both parachutes were generated for fluid-structure interaction (FSI) simulation. The penalty function and the arbitrary Lagrangian-Eulerian (ALE) method were employed in the FSI simulation. To validate the numerical model for FSI simulation, at first the single parachute of the twin-parachute was used for the FSI simulation, the predicted inflation times for both types of parachute were compared with the experimental data. The computed results are in good agreement with experimental data. As a result, the inflation times were predicted with twin-parachute for both kinds of parachute. On the basis of the locations of ejected seats after the separation of seat and pilot, the initial locations and orientations of twin-parachute were also obtained. The numerical simulations for both kinds of parachute were performed by the FSI method, respectively. Our results illustrate that when the interval time for two seats ejected is greater than 0.25s, two pilots attached the twin-parachute are safe, and the twin-parachute would not interfere each other. Moreover, our results also indicate that the FSI simulation for twin-parachute inflation process is feasible for engineering applications and have a great potential for wide use.

Sign in / Sign up

Export Citation Format

Share Document