Study of methods for estimating the viscosity coefficient of metals

2021 ◽  
Author(s):  
S.V. Serikov ◽  
I.K. Ustinov ◽  
O.V. Sulina
Keyword(s):  
Dynamic Viscosity ◽  
Theoretical Study ◽  
Human Life ◽  
Viscosity Coefficient ◽  
Practical Significance ◽  
Accurate Assessment ◽  
Viscosity Coefficients ◽  
Dynamic Yield Strength ◽  
Dynamic Yield ◽  
Problem Setting

Problem setting. The coefficient of dynamic viscosity of metals is used in many branches of human life, but its search, for a more accurate assessment and interpretation, is currently insufficiently studied due to the variety of its application [1-4], as well as due to the uncertainty of the constant parameters of the environment in which it is applied or investigated. Target. Consider a number of known methods for estimating the viscosity coefficients of metals at different ranges of strain patterns. Results. The methods considered for estimating the viscosity coefficient of metals, during their scientific and theoretical study, did not give an unambiguous answer for determining the viscosity of metals. Practical significance. Further study of the dynamic yield strength and the dynamic viscosity coefficient of metals is necessary to achieve more complete results of the method of evaluating the viscosity coefficient of metals.

scholarly journals Politicization of Religion in Theoretical and Terminological Understanding

2021 ◽  
Vol 1 (1) ◽  
pp. 27-40
Author(s):  
M. Kh. Abdullaev
Keyword(s):  
Mutual Influence ◽  
Human Life ◽  
Religion And Politics ◽  
Political Activity ◽  
Practical Significance ◽  
The Political ◽  
Spiritual Values ◽  
Theoretical Understanding ◽  
Political Role ◽  
The Rich

The article is devoted to an actual interdisciplinary problem at the intersection of political science and religious studies – the discourse of the political in religion, the politicization of religion, the artificial transfer of purely spiritual values, phenomena and categories into the political field in order to use religion for political purposes. The author considers the problem from two angles: (1) the politicization of religion for mercenary purposes and (2) the clergy’s political activity based on a deliberately politicized religious teaching that has a strong political platform (ideology) at its core. This study is purely theoretical, and nevertheless the author undertakes a number of empirical digressions in order to demonstrate how the politicization of religion manifests itself in the socio-political sphere of human life. Thus, the main problem of the study should be designated as a theoretical understanding and disclosure of the practical significance (i.e., risks and effects) of the religion politicization’s negativity and how it could effect on religious groups. The article identifies the objective factors of the mutual influence of religion and politics, the presence of strong political origins in a number of creeds, and the rich historical experience of the political role of faith in society.

scholarly journals Contribution of Viscous Forces to Avalanche Dynamics

1989 ◽  
Vol 13 ◽  
pp. 202-206 ◽  
Author(s):  
K. Nishimura ◽  
N. Maeno
Keyword(s):  
Dry Friction ◽  
Kinematic Viscosity ◽  
Viscosity Coefficient ◽  
Viscous Force ◽  
Viscous Resistance ◽  
Resistance Factors ◽  
Viscous Forces ◽  
Viscosity Coefficients ◽  
Avalanche Dynamics ◽  
The Individual

Mini-avalanche systems were constructed both in a low-temperature laboratory and in a snowfield, and the behaviour of the flowing snow was observed in each case. Velocity profiles for the individual snow particles were determined and these implied that a viscous force, which has been neglected in most previous numerical simulations of snow-avalanche motion, needs to be taken into account for many avalanches. Kinematic viscosity coefficients for the fluidized snow were also measured using a modified Stormer-type viscometer. Substituting the dry-friction value and the kinematic viscosity coefficient for fluidized snow into the equation for avalanche motion, numerical simulation of natural events was achieved for the Shiai-dani region. Taking viscous resistance factors into account led to the conclusion that the magnitude of turbulent resistance of snow in avalanche systems is probably much smaller than that represented by the values previously in use.

scholarly journals Объемная вязкость суспензии наночастиц оксида кремния

2020 ◽  
Vol 46 (12) ◽  
pp. 37
Author(s):  
М.И. Пряжников ◽  
А.В. Минаков
Keyword(s):  
Attenuation Coefficient ◽  
Bulk Viscosity ◽  
Dynamic Viscosity ◽  
Aqueous Suspension ◽  
Sio2 Nanoparticles ◽  
Nanoparticle Concentration ◽  
Viscosity Coefficients ◽  
Wide Range ◽  
First Time ◽  
Mass Concentrations

Data on the bulk viscosity of an aqueous suspension of SiO2 nanoparticles (Ludox TM-50) were obtained using an acoustic spectrometer for the first time. A wide range of mass concentrations of nanoparticles (from 1 to 50 wt.%) was considered. The spectra of the attenuation coefficient of ultrasound and the coefficients of longitudinal and dynamic viscosity were measured. The dependences of the dynamic and bulk viscosity coefficients of the suspensions on the nanoparticle concentration were obtained.

Measurement of Dynamic Stress and Strain in Tensile Test Specimens

1944 ◽  
Vol 11 (2) ◽  
pp. A65-A71
Author(s):  
R. O. Fehr ◽  
E. R. Parker ◽  
D. J. DeMicheal
Keyword(s):  
Tensile Strength ◽  
Yield Strength ◽  
Testing Machine ◽  
Impact Testing ◽  
High Rate ◽  
Stress And Strain ◽  
Dynamic Tensile Strength ◽  
Dynamic Yield Strength ◽  
Dynamic Yield ◽  
Cold Rolled

Abstract In the investigation detailed in this paper, the tensile strength, the yield strength, and the breakage energy of test specimens (cold-rolled steel and dural) were measured while the specimens were being broken by a force applied at a high rate of speed in a commercial high-velocity impact-testing machine. The dynamic tensile strength, the dynamic yield strength and the dynamic breakage energy were found to be higher than the static values up to the maximum impact velocities of these tests (100 fps). The paper contains: (1) A presentation of some results of these tests. (2) A description of the technique used. (3) A description of the analysis used.

scholarly journals Calibration of Discrete-Element-Method Parameters for Cohesive Materials Using Dynamic-Yield-Strength and Shear-Cell Experiments

Processes ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 278 ◽  
Author(s):  
Subhodh Karkala ◽  
Nathan Davis ◽  
Carl Wassgren ◽  
Yanxiang Shi ◽  
Xue Liu ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Surface Energy ◽  
Yield Strength ◽  
Discrete Element Method ◽  
Critical State ◽  
Discrete Element ◽  
Shear Cell ◽  
Dynamic Yield Strength ◽  
Dynamic Yield ◽  
Friction Parameters

This study tested the effectiveness of using dynamic yield strength (DYS) and shear-cell experiments to calibrate the following discrete-element-method (DEM) parameters: surface energy, and the coefficients of sliding and rolling friction. These experiments were carried out on cohesive granules, and DEM models were developed for these experiment setups using the JKR cohesion contact model. Parameter-sensitivity analysis on the DYS model showed that the DYS results in the simulations were highly sensitive to surface energy and were also impacted by the values of the two friction coefficients. These results indicated that the DYS model could be used to calibrate the surface energy parameter once the friction coefficients were fixed. Shear-cell sensitivity analysis study found that the influence of surface energy on the critical-state shear value cannot be neglected. It was inferred that the shear-cell model has to be used together with the DYS model to identify the right set of friction parameters. Next, surface energy was calibrated using DYS simulations for a chosen set of friction parameters. Calibrations were successfully conducted for simulations involving experimentally sized particles, scaled-up particles, a different shear modulus, and a different set of friction parameters. In all these cases, the simulation DYS results were found to be linearly correlated with surface energy and were within 5% of the experimental DYS result. Shear-cell simulations were then used to compare calibrated surface-energy values for the scaled-up particles with the experimentally sized particles. Both the simulations resulted in similar critical-state shear values. Finally, it was demonstrated that a combination of DYS and shear-cell simulations could be used to compare two sets of friction parameters and their corresponding calibrated surface energy values to identify the set of parameters that better represent the flow behavior demonstrated by the experimental system.

Influence of Dynamic Viscosity on Automatic Dynamic Balance

2010 ◽  
Vol 164 ◽  
pp. 127-132 ◽  
Author(s):  
Marijonas Bogdevicius ◽  
Jolanta Janutėnienė
Keyword(s):  
Numerical Analysis ◽  
Theoretical Approach ◽  
Dynamic Viscosity ◽  
Lagrange Equation ◽  
Dynamic Balance ◽  
Viscosity Coefficient ◽  
Dynamic Equations ◽  
Linear Character ◽  
Optimal Value ◽  
And Behavior

The paper deals with analysis of dynamic stability and behavior of automatic dynamic balance (ADB) by applying theoretical approach. Differential equations of the considered system were established using Lagrange equation. Numerical analysis of the dynamic equations was performed and influence of dynamic viscosity coefficient on self-balancing process was estimated. It is demonstrated that the balancing time decreases in non-linear character. The optimal value of dynamic viscosity for achieving minimal balancing time can be determined for the analyzed system.

The Dynamic Yield Strength of Steel at an Intermediate Rate of Loading

1948 ◽  
Vol 159 (1) ◽  
pp. 11-23 ◽  
Author(s):  
A. F. C. Brown ◽  
R. Edmonds
Keyword(s):  
Yield Strength ◽  
Alloy Steel ◽  
Underwater Explosion ◽  
Low Alloy Steel ◽  
Heat Treated ◽  
Static Tensile ◽  
Static Yield ◽  
Dynamic Yield Strength ◽  
Dynamic Yield ◽  
Rate Of Loading

A comparison has been made between the dynamic and static tensile yield strengths of eight steels varying from mild steel to a heat-treated low-alloy steel, the rate of loading in the dynamic tests being such as would occur in a ship under the action of an underwater explosion. The dynamic yield strength of the steels with low static strength was 20–30 per cent greater than their static yield strength but, for the stronger steels, the increase was less, being negligible in the case of the heat-treated low-alloy steel. This result conforms with the findings of other investigators, and shows that any increase in strength under the dynamic loading considered is too small to be of importance in design.

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