Vibratory Conveying by Harmonic Longitudinal and Polyharmonic Normal Vibrations of Inclined Conveying Track

2021 ◽  
pp. 1-14
Author(s):  
Ihor Vrublevskyi
Keyword(s):  
Inclination Angle ◽  
Normal Vibration ◽  
Longitudinal Vibration ◽  
Frictional Coefficient ◽  
Material Point ◽  
Normal Vibrations ◽  
Dimensionless Parameters ◽  
Optimal Values ◽  
Vibration Parameters ◽  
Angle Parameter

Abstract Vibratory conveying of a material point by harmonic longitudinal and polyharmonic normal vibrations of an inclined conveying surface is considered. The dependence of dimensionless conveying velocity – a ratio of velocity to the product of frequency and amplitude of longitudinal vibration – on several dimensionless parameters is investigated in the moving modes without hopping. Maximal conveying velocity is achieved at the certain values of normal vibration amplitudes and phase difference angle between the longitudinal and normal vibrations, which are called optimal. Their values are dependent on two dimensionless parameters: the inclination angle parameter – a ratio of an inclination angle tangent to a frictional coefficient, the intensive vibration coefficient – a ratio of the longitudinal amplitude of vibration to the amplitude of the first harmonic of normal vibration and frictional coefficient. In a condition of the intensive longitudinal vibration, when its amplitude significantly greater than amplitudes of normal vibration, dimensionless velocity is almost independent of the intensive vibration parameter and it depends only on inclination angle parameter, i.e. on inclination angle and frictional coefficient. The optimal values of harmonics' amplitudes of polyharmonic normal vibration are determined in dependence of inclination angle parameter with the number of harmonics from 2 to 7. The graphs of considered dependencies are presented and the most important values of parameters are presented in the table. Conclusions are made to determine the optimal vibration parameters and the problems of further research are indicated. The considered vibrations can be used in different vibratory conveying devices with electromagnetic drives.

scholarly journals Optimization of vibratory conveying upward by inclined track with polyharmonic normal vibrations

2020 ◽  
Vol 6 (2) ◽  
pp. 34-42
Author(s):  
Іgor Vrublevskyi ◽  
Keyword(s):  
Inclination Angle ◽  
Harmonic Balance ◽  
Normal Vibration ◽  
Frictional Coefficient ◽  
Harmonic Balance Method ◽  
Gravitational Acceleration ◽  
Normal Vibrations ◽  
Dimensionless Parameters ◽  
Optimal Values ◽  
Angle Parameter

The paper is devoted to the research of vibratory conveying of piece goods along an inclined track, performing harmonic longitudinal and polyharmonic normal vibrations. It is considered the conditions of reaching maximum conveying velocity at specified values of frequency and amplitude of longitudinal vibrations – the conditions of maximum dimensionless conveying velocity, depending on several dimensionless parameters in the moving modes without hopping. These dimensionless parameters are the inclination angle parameter – a ratio of an inclination angle tangent to a frictional coefficient, the intensive vibration coefficient – a ratio of the longitudinal amplitude of vibration to the amplitude of the first harmonic of normal vibration and frictional coefficient. Maximal conveying velocity is achieved at the certain values of normal vibration amplitudes and values of phase difference angles between longitudinal and normal vibrations, which are called optimal, and their values are dependent on these two dimensionless parameters, while maximum normal vibration acceleration should be equal to the gravitational acceleration. The research was made by approximate harmonic balance method and by numerical step-by-step integration method, which allows performing calculations with any given accuracy. The results obtained by the two methods are compared. To determine the maximal and optimal values of elevation angles, there are calculated the maximal value of the inclination angle parameter at which the value of dimensionless velocity is equal to zero, and the value of the inclination angle parameter at which a particle moves to a specified height in the minimum time. The optimal values of amplitudes of harmonics of polyharmonic normal vibration are determined in dependence on the inclination angle parameter with the number of harmonics from four to seven. The graphs of these dependencies are presented and the most important values of dimensionless parameters are presented in the table.

scholarly journals Use of principal component analysis in conjunction with soft computing methods for investigating total sediment load transferability from laboratory to field scale

2013 ◽  
Vol 45 (4-5) ◽  
pp. 540-550 ◽  
Author(s):  
Gokmen Tayfur ◽  
Yashar Karimi
Keyword(s):  
Principal Component Analysis ◽  
Soft Computing ◽  
Laboratory Data ◽  
Principal Component ◽  
Component Analysis ◽  
Empirical Methods ◽  
Field Scale ◽  
Dimensionless Parameters ◽  
Optimal Values ◽  
Total Sediment

This study quantitatively investigates the generalization from laboratory scale to field scale using the soft computing (expert) and the empirical methods. Principal component analysis is utilized to form the input vector for the expert methods. Five main dimensionless parameters are used in the input vector of artificial neural networks (ANN), calibrated with laboratory data, to predict field total sediment loads. In addition, nonlinear equations are constructed based upon the same dimensionless parameters. The optimal values of the exponents and constants of the equations are obtained by the genetic algorithm (GA) method using the laboratory data. The performance of the so-developed ANN and GA based models are compared against the field data and those of the existing empirical methods, namely Bagnold, Ackers and White, and Van Rijn. The results show that ANN outperforms the empirical methods. The results also show that the expert models, calibrated with laboratory data, are capable of predicting field total loads and thus proving their transferability capability. The transferability is also investigated by a newly proposed equation which is based on the Bagnold approach. The optimal values of the coefficients of this equation are obtained by the GA. The performance of the proposed equation is found to be very efficient.

scholarly journals Results of Theoretical Definition of Structural and Kinematic Parameters of Peeling Machine Working Elements

2020 ◽  
Vol 30 (4) ◽  
pp. 594-608
Author(s):  
Alexander V. Anisimov ◽  
Feliks Ya. Rudik
Keyword(s):  
Angular Velocity ◽  
Inclination Angle ◽  
Material Point ◽  
Machine Design ◽  
Cylinder Surface ◽  
Kinematic Parameters ◽  
Energy Assessment ◽  
Annular Gap ◽  
Working Bodies ◽  
Definition Of

Introduction. Peeling the moistened grains before grinding allows removing most of the outer shells with impurities on them from the grain surface. At the present time, the most commonly used machines for peeling are devices operating on the principle of “compression and friction”, in which the grains move along the friction surfaces of the working bodies. The aim of this study is to define and select structural and kinematic parameters of the machine working bodies, which would most effectively perform the process of peeling, and to make energy assessment of grain peeling. Materials and Methods. To identify the dependence of the machine design and operating parameters on the inclination angle and punching angle of the sieve cylinder, a diagram of the movement of the grain along the inclined cylinder was drawn up using elements of the theory of the motion of material point on rough surfaces. The motion of grains on the cylinder surface is analyzed by the methods of analytical dynamics. Results. The values of the geometric parameters of the particle position at point A are expressed as a function of the cylinder inclination angle α and the angle characterizing the shape of the inclined line of stamping of the cylinder β. Energy assessment of grain peeling process was made. With the radius of the sieve cylinder R0 = 0.135 m, the width of the working annular gap к = 0.01 m, the length of the cylinder L = 0.4 m, the horizontal arrangement of the cylinder, the angular velocity of the shaft ω = 90 rad/s, the angle of inclination of the stamping β = 22º, the calculated power was P = 4.5 kW. Discussion and Conclusion. As a result of analyzing the motion trajectory of the grain located on the cylinder surface, there have been proposed the formulas relating the shape of the inclined punching line of the cylinder, characterized by the angle β, to the inclination angle α, the radius R0 of the cylinder, the shaft angular velocity and the grain frictional properties. The obtained analytical dependencies can be used for the approximate definition of the peeling machine design and kinematic parameters.

Research on the mechanism of drag reduction by wall vibration through Lattice Boltzmann method

2020 ◽  
Vol 34 (27) ◽  
pp. 2050295
Author(s):  
Jia Zhen Zhao ◽  
Guang Pan ◽  
Shan Gao
Keyword(s):  
Drag Reduction ◽  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Normal Vibration ◽  
Liquid Interface ◽  
Geometry Model ◽  
Vibration Parameters ◽  
Solid Liquid Interface ◽  
Boltzmann Method ◽  
Solid Liquid

In this paper, the hydrodynamics of streamwise and normal vibration wall are studied using the Lattice Boltzmann method. Firstly, based on the two-dimensional flow geometry model, which is made up of flat wall and water fluid, the characters of the fluid near the streamwise and normal vibration wall are simulated under the condition of mutative vibration parameters. By rigorous data treating, some notable results such as the velocity distribution, density distribution curves of the flow field, and the frictional force of the solid-liquid interface are gained. Secondly, the reason of the change of frictional resistance at the solid-liquid interface by wall vibration are studied. And the results are evidence that well drag reduction effect can be obtained by applying appropriate flow vibration parameters to the solid wall. In addition, the reduction in fluid density near the solid-liquid wall is another significant cause behind the frictional drag decrease.

scholarly journals Спектральная диагностика динамики образования гомосопряженного комплекса [HCN.H.NCH]-=SUP=-+-=/SUP=-

2020 ◽  
Vol 128 (4) ◽  
pp. 480
Author(s):  
Г.С. Денисов ◽  
С.М. Меликова ◽  
К.С. Рутковский ◽  
К.Г. Тохадзе
Keyword(s):  
Proton Transfer ◽  
Transfer Reaction ◽  
Reaction Path ◽  
Longitudinal Vibration ◽  
Proton Transfer Reaction ◽  
Mechanical Analysis ◽  
Frequency Change ◽  
Normal Vibrations ◽  
Frequencies Of Normal Vibrations ◽  
Reaction Profile

A quantum-mechanical analysis of the manifestations of the NHN hydrogen bond in the vibrational spectra of the [HCN.H.NCH] + linear complex along the proton transfer reaction profile is given, and the laws governing the diagnostic parameters — potential descriptors of the dynamics of this process — are established. The surface of the potential energy and harmonic frequencies of normal vibrations along the profile of the proton transfer reaction path in the system studied are calculated. It has been shown that when the [HCNH] + and NCH fragments come closer together, a noticeable distortion of the forms of their skeletal vibrations occurs, up to complete mixing into the symmetric and antisymmetric forms. The frequency of the longitudinal vibration of the central proton ν (NH) varies along the reaction path from ~ 3600 to ~ 500 cm-1. In the region of intersection of the terms ν (NH) and ν (CN) an abrupt nature of frequency change is detected.

Kinematics Analysis on Ultrasonic Deep Rolling with Longitudinal-Torsional Vibration

2012 ◽  
Vol 630 ◽  
pp. 148-152 ◽  
Author(s):  
Ao Mei Luo ◽  
Jian Xin Zheng ◽  
Hao Qiong Wu
Keyword(s):  
Process Parameters ◽  
Torsional Vibration ◽  
Amplitude Ratio ◽  
Longitudinal Vibration ◽  
Rotation Frequency ◽  
Rolling Process ◽  
Acoustic System ◽  
Deep Rolling ◽  
Optimization Of Process Parameters ◽  
Vibration Parameters

The kinematics model was built based on the principle of ultrasonic deep rolling (UDR) with longitudinal-torsional vibration (LTV), and the trajectory equations of any particles on edge of the roller involved in the process were given; the influences of vibration parameters including phase angle, frequency of LTV, amplitude of longitudinal vibration, amplitude ratio and the rolling process parameters including roller radius, rolling depth, feed rate, the rotation frequency of roller on the trajectory, acoustic system design and processing quality were discussed. The results can provide theoretical basis for the design of acoustic system and optimization of process parameters.

Defects in Crystals

1968 ◽  
Vol 26 ◽  
pp. 244-245
Author(s):  
Kenneth R. Lawless
Keyword(s):  
Electron Microscope ◽  
Point Defects ◽  
Surface Defects ◽  
Chemical Properties ◽  
Material Point ◽  
Crystal Defects ◽  
Defects In Crystals ◽  
Irradiation Effects ◽  
Normal Lattice ◽  
Line Defects

One of the most important applications of the electron microscope in recent years has been to the observation of defects in crystals. Replica techniques have been widely utilized for many years for the observation of surface defects, but more recently the most striking use of the electron microscope has been for the direct observation of internal defects in crystals, utilizing the transmission of electrons through thin samples.Defects in crystals may be classified basically as point defects, line defects, and planar defects, all of which play an important role in determining the physical or chemical properties of a material. Point defects are of two types, either vacancies where individual atoms are missing from lattice sites, or interstitials where an atom is situated in between normal lattice sites. The so-called point defects most commonly observed are actually aggregates of either vacancies or interstitials. Details of crystal defects of this type are considered in the special session on “Irradiation Effects in Materials” and will not be considered in detail in this session.

Aneurysm Inclination Angle as the Predisposing Factor for the Occurrence of Rupture

2015 ◽  
Vol 76 (S 02) ◽  
Author(s):  
I. Nikolić ◽  
N. Repac ◽  
A. Janićijević ◽  
V. Šćepanović ◽  
L. Rasulić ◽  
...  
Keyword(s):  
Inclination Angle ◽  
Predisposing Factor

Effects of Inclination Angle on Archimedes Screw Generator Power Production with Constant Head

2021 ◽  
Vol 147 (3) ◽  
pp. 04021001
Author(s):  
Scott Simmons ◽  
Guilhem Dellinger ◽  
Murray Lyons ◽  
Abdelali Terfous ◽  
Abdellah Ghenaim ◽  
...  
Keyword(s):  
Inclination Angle ◽  
Power Production ◽  
Constant Head
Sign in / Sign up

Export Citation Format

Share Document