Dynamics of an isolated barotropic eddy on a beta-plane

1994 ◽  
Vol 264 ◽  
pp. 277-301 ◽  
Author(s):  
Gennady K. Korotaev ◽  
Alexander B. Fedotov
Keyword(s):  
Kinetic Energy ◽  
Analytical Solution ◽  
Numerical Experiment ◽  
Point Vortex ◽  
Vortex Sheet ◽  
The Other ◽  
Beta Plane ◽  
The Difference ◽  
Experimental Values ◽  
Good Agreement

The dynamics of a Gaussian isolated barotropic eddy on a β-plane is considered. The analytical solution of the evolution of an isolated vortex is constructed by analogy to the theory of a point vortex. The results of a numerical experiment are compared with the conclusions of the theory for the case of the Gaussian vortex. Characteristics of the vortex such as its radius, trajectory of movement, kinetic energy, residual vorticity, and the structure of the vortex are discussed. The analysis of the numerical results shows that the experimentally determined radius of the vortex, its energy, and residual vorticity are in good agreement with the theory. On the other hand there is a difference between analytical and experimental values of velocity components, and hence in the trajectory of the centre of the vortex. The location of the separatrix of the streak function and its saddle point are considered as important characteristics of the structure of the vortex. We consider the phenomenon of the generation of the vortex sheet connected with the separatrix location as a cause of the difference between the experimental and analytical estimates of the velocity of the vortex.

Energetics and Structural Effects of Boron Additive to Intermetallic Compound: γ-Tial

1990 ◽  
Vol 213 ◽  
Author(s):  
P.K. Khowash ◽  
D.L. Price ◽  
B.R. Cooper
Keyword(s):  
Intermetallic Compound ◽  
Total Energy ◽  
Site Selection ◽  
Lattice Structure ◽  
Practical Importance ◽  
The Difference ◽  
The Stability ◽  
Experimental Values ◽  
And Behavior ◽  
Good Agreement

ABSTRACTImproving the low temperature ductility of the intermetallic compound γ - TiAl by alloying with small concentrations of an additive is of great practical importance. The difference in site selection energy of the additive plays an important role in the stability and behavior of the alloy. For boron in L10 TiAl, we have calculated the site selection energy using linearized combination of muffin-tin orbitals (LMTO) total energy calculations. For pure γ - TiAl, we found the equilibrium lattice structure by minimizing the total energy, and obtained good agreement with the experimental values. With the introduction of boron, a relaxation of the lattice around the boron additive is expected. For boron additives, we have calculated the forces on each atom leading to the minimization of the total energy as a function of the ionic positions in order to obtain the “true” stable structure of the alloy.

Pb-free solders: Predicting of some physicochemical properties of Ag–Cu–Sn material at different temperatures

2016 ◽  
Vol 15 (07) ◽  
pp. 1650062 ◽  
Author(s):  
Rachida M’chaar ◽  
Mouloud El Moudane ◽  
Abdelaziz Sabbar ◽  
Ahmed Ghanimi
Keyword(s):  
Surface Tension ◽  
Physicochemical Properties ◽  
Molar Volume ◽  
The Other ◽  
Ternary Alloys ◽  
Other Hand ◽  
Different Temperatures ◽  
Experimental Values ◽  
Increasing Temperature ◽  
Good Agreement

In this paper, the surface tension, molar volume and density of liquid Ag–Cu–Sn alloys have been calculated using Kohler, Muggianu, Toop, and Hillert models. In addition, the surface tension and viscosity of the Ag–Cu–Sn ternary alloys at different temperatures have been predicted on the basis of Guggenheim and Seetharaman–Sichen equations, respectively. The results show that density and viscosity decrease with increasing tin and increasing temperature for the all studied models. While the surface tension shows a different tendency, especially for the Kohler and Muggianu symmetric models. On the other hand, the molar volume increases with increase of temperature and tin compositions. The calculated values of surface tension and density of Ag–Cu–Sn alloys are compared with the available experimental values and a good agreement was observed.

Compressive Strain Limits of High-Strength Linepipes

2008 ◽  
Author(s):  
Nobuhisa Suzuki ◽  
Joe Zhou ◽  
Masao Toyoda
Keyword(s):  
Analytical Solution ◽  
High Strain ◽  
Pressure Effect ◽  
Compressive Strain ◽  
High Strength ◽  
The Other ◽  
Conversion Function ◽  
Strain Hardening Exponent ◽  
Pure Bending ◽  
Good Agreement

Regression formulas are developed in order to predict the critical compressive strain of X80 linepipes subjected to pure bending. The regression formulas were derived using an analytical solution and two conversion functions. The analytical solution was previously proposed to calculate the critical compressive strain of a pipe subjected to axial compression, where hardening properties are taken into account. The original analytical solution was rewritten to include a strain-hardening exponent. Two conversion functions are defined to connect two critical compressive strains of a pipe under different loading conditions. One is a pressure-effect conversion function which connects two critical compressive strains of a pipe without and with internal pressure, respectively. The other is a compression-bending conversion function which also connects two critical compressive strains of a pressurized pipe which is subjected to compression and bending. The regression formulas were obtained using the improved analytical solution and the two conversion functions. The regression formulas yield good agreement with FEA results especially for high-strain linepipes.

scholarly journals An Approximate Analytical Solution of Sloshing Frequencies for a Liquid in Various Shape Aqueducts

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yuchun Li ◽  
Zhuang Wang
Keyword(s):  
Analytical Solution ◽  
Approximate Method ◽  
Approximate Analytical Solution ◽  
Ritz Method ◽  
Approximate Solutions ◽  
The Other ◽  
Engineering Applications ◽  
Tuned Liquid Dampers ◽  
Liquid Dampers ◽  
Experimental Values

An approximate analytical solution of sloshing frequencies for a liquid in the various shape aqueducts is formulated by using the Ritz method. The present approximate method is, respectively, applied to find the sloshing frequencies of the liquid in rectangular, trapezoid, oval, circular, U-shaped tanks (aqueducts), and various shape tuned liquid dampers (TLD). The first three antisymmetric and symmetric frequencies by the present approach are within 5% accuracy compared to the other analytical, numerical, and experimental values. The approximate solutions of this paper for the various shape aqueducts are acceptable to the engineering applications.

Numerical Methods for the Photoelastic Technique using Phase Shifting

2015 ◽  
Vol 31 (4) ◽  
pp. 355-367
Author(s):  
C. A. Magalhaes ◽  
P. S. Neto ◽  
P. A. A. Magalhaes ◽  
C. S. de Barcellos
Keyword(s):  
Numerical Methods ◽  
Numerical Technique ◽  
Random Noise ◽  
Phase Shifting ◽  
The Other ◽  
Object A ◽  
Digital Photoelasticity ◽  
Phase Shifting Method ◽  
The Difference ◽  
Experimental Values

AbstractThe objective of this research is to find new equations for a novel phase-shifting method in digital photoelasticity. Some innovations are proposed. In terms of phase-shifting, only the analyzer is rotated, and the other equations are deduced by applying a new numerical technique instead of the usual algebraic techniques. This approach can be used to calculate a larger sequence of images. Each image represents a pattern and a measurement of the stresses present in the object. A reduction in the difference between the theoretical and experimental values of stresses was obtained by increasing the number of images in the equations for calculating phase. Every photographic image has errors and random noise, but the uncertainties due to these effects can be reduced with a larger number of observations.

Slow waves of boiling under hot water depressurization

2000 ◽  
Vol 413 ◽  
pp. 149-180 ◽  
Author(s):  
OLEG E. IVASHNYOV ◽  
MARINA N. IVASHNEVA ◽  
NICKOLAI N. SMIRNOV
Keyword(s):  
Numerical Experiment ◽  
Slow Wave ◽  
Experimental Studies ◽  
Physical Experiment ◽  
Hot Water ◽  
Slow Waves ◽  
Phase Velocities ◽  
Bubble Breakup ◽  
The Difference ◽  
Good Agreement

Experimental studies of hot water depressurization show that the pressure in a vessel, just after it is opened, drops much lower than the pressure of saturation but the liquid does not boil uniformly throughout the vessel. Essentially, liquid boiling begins only on the arrival of a ‘slow wave’ of rarefaction which moves at a low speed of approximately 10 m s−1 from the open end deep into the vessel.To explain this phenomenon we suggest a model that takes into account the difference in phase velocities. Although this difference in bubble flows is only about 1 m s−1 it proves to be sufficient to cause bubble breakup. Using this model we obtained the ‘slow wave of boiling’ in a numerical experiment that was in good agreement with the physical experiment.

The instability of capillary jets

1975 ◽  
Vol 68 (3) ◽  
pp. 477-495 ◽  
Author(s):  
Arthur M. Sterling ◽  
C. A. Sleicher
Keyword(s):  
Velocity Profile ◽  
Surrounding Medium ◽  
Aerodynamic Interaction ◽  
The Difference ◽  
Capillary Jets ◽  
Experimental Values ◽  
Semi Empirical ◽  
Axisymmetric Disturbances ◽  
Laminar Pipe Flow ◽  
Good Agreement

At high jet velocity the aerodynamic interaction between a capillary jet and the surrounding medium leads to an enhanced growth rate of axisymmetric disturbances. The available theories which account for this effect fail to agree with experimental observations. The difference is attributed, in part, to the relaxation of the velocity profile in jets formed by fully developed laminar pipe flow. The profile relaxation has a destabilizing effect just as does the aerodynamic interaction. In the absence of velocity-profile relaxation it is shown that the available theories overestimate the aerodynamic effect. A consideration of the viscosity of the ambient fluid yields a semi-empirical modification to the theory which shows good agreement with experimental values.

scholarly journals Theoretical Study of Isospin Mixing States with T> 0 in sd Even-Even N=Z Nuclei Using Shell Model

2021 ◽  
Vol 12 (2) ◽  
pp. 2470-2475
Author(s):  
Anwer A. Al-Sammarraie , Et. al.
Keyword(s):  
Shell Model ◽  
Excited States ◽  
Transition Probabilities ◽  
Energy Levels ◽  
Electric Quadrupole ◽  
Electric Quadrupole Transition ◽  
The Difference ◽  
Experimental Values ◽  
Mixing States ◽  
Good Agreement

Nuclear excited states with T > 0 in sd even-even N=Z  nuclei have been studied by using shell model. The calculations have employed the USDB Hamiltonian in order to predict the energy levels, the reduced electric quadrupole transition probabilities and reduced magnetic dipole transition probabilities. The study also include the average number of nucleons in each sd- active orbitals. The results compared with available experimental data.  The comparison showed a good agreement between theoretical and experimental energy sates for most of the states studied in this work. On the other hand there was a difference between theoretical and experimental values of transition probabilities, but it can be said that it remained within the acceptable range of the difference.

Study on Evaluation Models of Management Data for Decommissioning of FUGEN

2010 ◽  
Author(s):  
Yuji Shibahara ◽  
Masanori Izumi ◽  
Takashi Nanko ◽  
Mitsuo Tachibana ◽  
Tsutomu Ishigami
Keyword(s):  
Power Plant ◽  
Nuclear Power ◽  
The Other ◽  
Actual Data ◽  
Preparation Process ◽  
Working Space ◽  
Evaluation Models ◽  
The Difference ◽  
Scale Difference ◽  
Good Agreement

In the Fugen nuclear power plant (FUGEN), the dismantling of equipments in the turbine building has started in 2008, and the dismantling of equipments around the reactor is scheduled around in 2015. To evaluate the management data on this dismantling of equipments around reactor appropriately, it is very important to study whether the conventional evaluation models have the applicability for FUGEN or not. Thus, the management data on the dismantling of equipments in 3rd/4th feedwater heater room conducted in 2008 was calculated with the conventional evaluation models. The conventional evaluation models were made by data obtained from Japan Power Demonstration Reactor (JPDR) decommissioning program. It was found that there were large differences between the calculated values and the actual data. For finding the cause in the difference between them, the dismantling of equipments in 3rd/4th feedwater heater room was divided into three processes: i) the preparation process, ii) the dismantling process, and iii) the clean-up process. In the both process of preparation and clean-up, the calculated values were smaller than the actual data. These were mostly caused by the plant scale difference between JPDR and FUGEN, because the conventional evaluation models were built by analyzing the actual data on the decommissioning of JPDR which is smaller than FUGEN. The primary expression depending on the area of working space was built as new evaluation models for the preparation and clean-up processes. In the dismantling process, on the other hand, it was found that there were characteristic differences in the dismantling of feedwater heater as follows: 1) the calculated values were significantly larger than the actual data, 2) the actual data for the dismantling of 3rd feedwater heater was larger than that of 4th one, though these equipments were almost same weight. It was found that these were brought by the difference in the descriptions of dismantling of feedwater heaters, and the new evaluation models reflecting the descriptions of dismantling were built for the appropriate evaluation of the management data. The calculated values with the new evaluation models for each process showed the good agreement with the actual data. In this report, study on evaluation models of management data for dismantling of equipments in the feedwater heater room will be described.

scholarly journals Coupling Influence on Signal Readout of a Dual-Parameter LC Resonant System

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Jijun Xiong ◽  
Tanyong Wei ◽  
Tao Luo ◽  
Qiulin Tan ◽  
Chenyang Xue ◽  
...  
Keyword(s):  
Printed Circuit Board ◽  
Test System ◽  
The Other ◽  
Circuit Board ◽  
Coupling Coefficients ◽  
Matlab Simulation ◽  
Spiral Coil ◽  
Readout Signal ◽  
The Difference ◽  
Good Agreement

Dual-parameter inductive-capacitive (LC) resonant sensor is gradually becoming the measurement trend in complex harsh environments; however, the coupling between inductors greatly affects the readout signal, which becomes very difficult to resolve by means of simple mathematical tools. By changing the values of specific variables in a MATLAB code, the influence of coupling between coils on the readout signal is analyzed. Our preliminary conclusions underline that changing the coupling to antenna greatly affects the readout signal, but it simultaneously influences the other signal. Whenf01=f02, it is better to broaden the difference between the two coupling coefficientsk1andk2. On the other side, whenf01is smaller thanf02, it is better to decrease the coupling between sensor inductorsk12, in order to obtain two readout signals averaged in strength. Finally, a test system including a discrete capacitor soldered to a printed circuit board (PCB) based planar spiral coil is built, and the readout signals under different relative inductors positions are analyzed. All experimental results are in good agreement with the results of the MATLAB simulation.

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