scholarly journals RESISTANCE OF THICK-WALLED BARRIER IN PENETRATION OF A SOLID BODY

2021 ◽  
Vol 2 (4) ◽  
pp. 164-172
Author(s):  
Anvar I. Chanyshev ◽  
Olga E. Belousova ◽  
Olga A. Luk’yashko
Keyword(s):  
Solid Body ◽  
Equation Of Motion ◽  
Resistance Force ◽  
Resistance Function ◽  
Single Arc ◽  
Barrier Resistance ◽  
Solid Bodies

The authors discuss bursting of barriers by solid bodies. The resistance function changes along a single-arc sinusoid. The equation of motion of a solid body is solved. The velocity of the drift hammer to reach the back of the barrier is determined. The alternative initial velocities such that the solid body is jammed in the barrier or is shot outside the barrier are examined. Determination of the barrier resistance force versus the shoot-out velocity of the drift hammer is discussed.

scholarly journals On the substantiation of the effectiveness of air-centrifugal separation and dust cleaning of seed heap of herbs after the grate device

2019 ◽  
pp. 80-85
Author(s):  
Tverdokhlib Igor ◽  
Spirin Anatoly
Keyword(s):  
Seed Production ◽  
Air Flow ◽  
Inertia Force ◽  
Resistance Force ◽  
Centrifugal Separation ◽  
Separation Unit ◽  
Production Technologies ◽  
Assembly Technology ◽  
One Machine

The agrobiological and physico-mechanical properties of leguminous seed plants do not allow them to be harvested without loss exclusively by combine technologies. One way to increase the productivity of the seed production process is to include stationary machines in the assembly technology for wiping and separating seed heaps. Combining these important operations with one machine will further increase the efficiency of legume seed production technologies. This work is devoted to considering ways to increase the efficiency of air-centrifugal separation and dust cleaning seed heaps. A review of recent studies and publications has shown that there is a sufficient methodological basis for determining the parameters of the process of separation of the heap and purification of the exhaust air. An analysis of the publications made it possible to determine the purpose of the research, which is to increase the efficiency of the grater-separation unit by substantiating its scheme and the method of theoretical determination of the parameters of the separation process. According to the results of previous studies, a structural scheme of the grater-separating device is proposed. The main elements of the block are a grater device, which consists of a motionless and movable corrugated discs of the separating device with separate channels for the exit of seeds, straw part of the heap, air. To increase the efficiency of the cleaning process, a blade swirler and a louvre nozzle are placed in the separating device, which provide the air flow with rotational movement around the axis of the cyclone body. In theoretical studies of the motion of particles in a rotational air flow, the simplified assumption was adopted: the particles are spherical, do not deform, and do not interact with each other, the inertia force is directed along the radius of the cyclonic chamber, the tangential and axial components of the particle velocity are equal to the corresponding components of the air velocity, and the particle resistance force determined by the Stokes law, the force of attraction is much less than the centrifugal force, so we neglect it. The obtained formulas allow one to approximately determine the parameters of the cyclone device that will ensure the separation of the seeds of legumes.

scholarly journals ON OSCILLATIONS DESCRIBING A GENERALIZED DIFFERENTIAL RELAY EQUATION

2020 ◽  
pp. 53-60
Author(s):  
Vasiliy Olshansky ◽  
Stanislav Olshansky ◽  
Oleksіі Tokarchuk
Keyword(s):  
Differential Equation ◽  
Initial Conditions ◽  
Oscillatory System ◽  
Equation Of Motion ◽  
Resistance Force ◽  
Oscillatory Process ◽  
Initial Deviation ◽  
Approximate Analytical Solutions ◽  
Positive Exponent ◽  
Generalized Differential

The motion of an oscillatory system with one degree of freedom, described by the generalized Rayleigh differential equation, is considered. The generalization is achieved by replacing the cubic term, which expresses the dissipative strength of the equation of motion, by a power term with an arbitrary positive exponent. To study the oscillatory process involved the method of energy balance. Using it, an approximate differential equation of the envelope of the graph of the oscillatory process is compiled and its analytical solution is constructed from which it follows that quasilinear frictional self-oscillations are possible only when the exponent is greater than unity. The value of the amplitude of the self-oscillations in the steady state also depends on the value of the indicator. A compact formula for calculating this amplitude is derived. In the general case, the calculation involves the use of a gamma function table. In the case when the exponent is three, the amplitude turned out to be the same as in the asymptotic solution of the Rayleigh equation that Stoker constructed. The amplitude is independent of the initial conditions. Self-oscillations are impossible if the exponent is less than or equal to unity, since depending on the initial deviation of the system, oscillations either sway (instability of the movement is manifested) or the range decreases to zero with a limited number of cycles, which is usually observed with free oscillations of the oscillator with dry friction. These properties of the oscillatory system are also confirmed by numerical computer integration of the differential equation of motion for specific initial data. In the Maple environment, the oscillator trajectories are constructed for various values of the nonlinearity index in the expression of the viscous resistance force and a corresponding comparative analysis is carried out, which confirms the adequacy of approximate analytical solutions.

scholarly journals ЗОВНІШНЯ БАЛІСТИКА СНАРЯДУ БМ1 ВИПУЩЕНОГО З Т-12 (МТ-12)

World Science ◽  
2020 ◽  
Vol 1 (1(53)) ◽  
pp. 23-29
Author(s):  
Величко Лев Дмитрович ◽  
Горчинський Ігор Володимирович ◽  
Сорокатий Микола Іванович
Keyword(s):  
Atmospheric Pressure ◽  
Sound Speed ◽  
Functional Dependence ◽  
Resistance Force ◽  
Kinematic Parameters ◽  
Muzzle Velocity ◽  
Velocity Magnitude ◽  
Air Resistance ◽  
The Mathematical Model

The magnitudes of the kinematic parameters of projectiles motion in the air depends on deterministic (form of projectile, its mass, temperature of air and charge, atmospheric pressure, derivation) and nondeterministic (muzzle velocity, magnitude and direction of wind velocity) values. During the projectile movement, its weight and frontal air resistance force have a determining influence on its dynamics. In the article it is investigated proposed by authors the mathematical model of determination of the functional dependence of the magnitude of the frontal air resistance force of the projectile’s motion on its velocity, mass and caliber, geometric characteristics, temperature and density of air, atmospheric pressure, sound speed in air. Since the trajectory of movement of the BM1 projectile released from the T-12 (MT-12) is canopy, it is assumed that during the projectile’s flight the air temperature and atmospheric pressure are unchanged and equal to their value at the point of the gun.

scholarly journals New approaches to the determination of the density of the solid bodies

2017 ◽  
pp. 65-70
Author(s):  
V. V. Kulikov
Keyword(s):  
Basic Characteristic ◽  
Compressed Air ◽  
New Approaches ◽  
Laboratory Investigations ◽  
Definition Of ◽  
Solid Bodies

New approaches to a definition of the basic characteristic of the bodies - density, have suggested. To improve the technique of the caring out the laboratory investigations, increasing the safety of the investigations and preventing the damages of the diagnosed products in liquid medias, instead of caring out the traditional hydrostatic weighting of the studied samples (in liquids, in particular heavy immersion ones, demanding the special conditions of the safe usage), a method of the aerostatic weighting (a determination of the weight in a compressed air) and a method of the weighting in finely-dispersed loose materials have been considered.

scholarly journals Determination of meteoroid physical properties from tristatic radar observations

2008 ◽  
Vol 26 (8) ◽  
pp. 2217-2228 ◽  
Author(s):  
J. Kero ◽  
C. Szasz ◽  
A. Pellinen-Wannberg ◽  
G. Wannberg ◽  
A. Westman ◽  
...  
Keyword(s):  
Cross Sections ◽  
Equation Of Motion ◽  
Momentum Equation ◽  
Radar System ◽  
Radar Target ◽  
Radar Cross Sections ◽  
The Common ◽  
Head Echo ◽  
Uhf Radar

Abstract. In this work we give a review of the meteor head echo observations carried out with the tristatic 930 MHz EISCAT UHF radar system during four 24 h runs between 2002 and 2005 and compare these with earlier observations. A total number of 410 tristatic meteors were observed. We describe a method to determine the position of a compact radar target in the common volume monitored by the three receivers and demonstrate its applicability for meteor studies. The inferred positions of the meteor targets have been utilized to estimate their velocities, decelerations and directions of arrival as well as their radar cross sections with unprecedented accuracy. The velocity distribution of the meteoroids is bimodal with peaks at 35–40 km/s and 55–60 km/s, and ranges from 19–70 km/s. The estimated masses are between 10−9–10−5.5 kg. There are very few detections below 30 km/s. The observations are clearly biased to high-velocity meteoroids, but not so biased against slow meteoroids as has been presumed from previous tristatic measurements. Finally, we discuss how the radial deceleration observed with a monostatic radar depends on the meteoroid velocity and the angle between the trajectory and the beam. The finite beamwidth leads to underestimated meteoroid masses if radial velocity and deceleration of meteoroids approaching the radar are used as estimates of the true quantities in a momentum equation of motion.

scholarly journals Utilizing Dynamic Stability to Orient Parts

1987 ◽  
Vol 54 (4) ◽  
pp. 961-966 ◽  
Author(s):  
N. C. Singer ◽  
W. P. Seering
Keyword(s):  
Dynamic Behavior ◽  
Dynamic Stability ◽  
Solid Body ◽  
Dynamic Models ◽  
Oscillatory Motion ◽  
Automatic Assembly ◽  
Moving Surface ◽  
Dynamic Behaviors ◽  
Solid Bodies

The intent of this research is to study the dynamic behavior of a solid body resting on a moving surface. Results of the study are then used to propose methods for controlling the orientation of parts in preparation for automatic assembly. Two dynamic models are discussed in detail. The first examines the impacts required to cause reorientation of a part. The second investigates the use of oscillatory motion to selectively reorient parts. This study demonstrates that the dynamic behaviors of solid bodies, under the conditions mentioned above, vary considerably with small changes in geometry or orientation.

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