scholarly journals PLANNING A MULTI-FACTOR EXPERIMENT FOR DETERMINING RATIONAL PARAMETERS OF THE VIBRATION MACHINE OPERATION

2020 ◽  
pp. 5-14
Author(s):  
Oleh Tsurkan ◽  
Ruslan Horbatiuk ◽  
Dmytro Prysiazhniuk
Keyword(s):  
Angular Velocity ◽  
Vibration Amplitude ◽  
Processing Time ◽  
Angular Speed ◽  
Drive Shaft ◽  
Technological Parameters ◽  
Vibration Machine ◽  
Working Chamber ◽  
Optimal Experiment ◽  
Multifactorial Experiment

The approaches and methods of improving the quality and efficiency of agricultural machinery repair are of priority importance in Ukraine today. The tough competitive environment in the interstate and domestic market of technical services dictates its own terms. One of the promising research methods is the planning of an experiment in the optimization of multifactorial processes, such as vibration strengthening processing of agricultural machinery parts. The object of the research in this article was the technological process of finishing, cleaning and strengthening processing of parts of tillage machines with their surface plastic vibration deformation. The purpose of the work was to plan a multifactorial experiment for the theoretical determination of the compromise parameters of the operation of a vibration machine with an activator of the movement of the working medium for strengthening the treatment of the working bodies of tillage machines. The task of the work was to: analyze research and publications on the basics of probability theory, mathematical statistics, foundations of correlation, variance and regression analyzes, planning an optimal experiment; obtain the coefficients of complex equations of multiple regression of the 2nd order and plot the dependence of the consumed energy consumption by the developed installation on the amplitude of oscillations of the working chamber, the amplitude of oscillations of the activator, angular velocity of the drive shaft of the working chamber, angular velocity of the drive shaft of the activator, processing time; the height of microroughnesses from the vibration amplitude of the working chamber, the vibration amplitude of the activator, the angular velocity of the drive shaft of the working chamber, the angular velocity of the drive shaft of the activator, the processing time; surface hardness on the vibration amplitude of the working chamber, vibration amplitude of the activator, angular velocity of the drive shaft of the working chamber, angular velocity of the drive shaft of the activator, processing time; based on the results of the research and testing of the developed installation on the basis of the constructed response surfaces of the processes under study, to determine the rational technological parameters of its operation, the compromise value of which can be obtained by the Cramer method in the mathematical environment "Mathcad 15". The research methodology was based on mathematical statistics, correlation, variance and regression analyzes, planning an optimal experiment. In scientific work, based on the results of a multifactorial experiment, a mathematical model was obtained in the form of multiple second-order regression, which adequately describes the technological process under study. Compromise technological parameters of the investigated process were obtained, which are: the amplitude of oscillations of the working chamber - 2-4 mm; the vibration amplitude of the activator is 1.5-2.5 mm; the angular speed of the drive shaft of the working chamber - 115-120 rad/s; the angular speed of the drive shaft of the activator 130-145 rad/s; processing time - 80 min.

scholarly journals Standardization of the technological parameters of vibratory abrasion as a tool for process reliability enhancement

2020 ◽  
Vol 175 ◽  
pp. 05006
Author(s):  
Galina Prokopetz ◽  
Anna Azarova ◽  
Anatoliy Prokopetz ◽  
Elena Murugova
Keyword(s):  
Wear Rate ◽  
Quality Indicators ◽  
Processing Time ◽  
General Structure ◽  
Oscillation Amplitude ◽  
Technological System ◽  
Technological Parameters ◽  
Working Chamber ◽  
Process Reliability ◽  
The Stability

This paper deals with the general structure of the technological system of vibration abrasive processing and main issues of ensuring the stability of quality indicators formed in the final vibration abrasive processing. The research results of the working chamber oscillation amplitude influence and processing time on the wear rate of the processing environment are presented. The sample of determining the wear tolerance of the processing environment based on the roughness tolerance is presented.

JUSTIFICATION OF THE POSSIBILITY OF RATIONING TECHNOLOGICAL PARAMETERS OF VIBROABRASIVE PROCESSING IN ORDER TO INCREASE THE RELIABILITY OF THE PROCESSING PROCESS

2020 ◽  
Author(s):  
G.A. Prokopets ◽  
◽  
A.A. Prokopets ◽  
T. Erina ◽  
◽  
...  
Keyword(s):  
Wear Rate ◽  
Quality Indicators ◽  
Processing Time ◽  
General Structure ◽  
Oscillation Amplitude ◽  
Technological System ◽  
Technological Parameters ◽  
Working Chamber ◽  
The Stability ◽  
Wear Tolerance

The paper considers the General structure of the technological system of vibration abrasive processing, the issues of ensuring the stability of quality indicators formed during the final vibration abrasive processing. The results of the study of the influence of the working chamber oscillation amplitude and processing time on the wear rate of the processing medium are presented. An example of determining the wear tolerance of the processing medium based on the roughness tolerance is given.

Low frequency vibratory cleaning of paint and rust contaminants from machines parts

2021 ◽  
pp. 095440542110314
Author(s):  
Dieudonne Essola ◽  
Achille Pandong Njomoue ◽  
Florence Offole ◽  
Cyrille Adiang Mezoue ◽  
Crick Nelson Zanga ◽  
...  
Keyword(s):  
Processing Time ◽  
Low Frequency ◽  
Processing Parameters ◽  
Vibration Machine ◽  
Optimal Processing ◽  
Low Frequency Oscillations ◽  
Experimental Parameters ◽  
Process Fluid ◽  
Full Factorial ◽  
Fluid Parameters

This work investigates the effect of low frequency vibratory processing for cleaning and washing various machine components parts from rusts and old paints deposits. The experimental investigation was carried out with special prepared samples that were weighted and exposed to paints and rust contaminants. These samples were treated in universal horizontal vibration machine UVHM 4 × 10 with different combination of instrumental processing medium, process fluid, machine amplitude and frequency of oscillations. They were periodically reweighted after processing and compared to etalon with control of quantity of dust that have been removed, sample cleanliness and also other functional parameters. Statistical analysis has been used to characterize ongoing process and full factorial analysis to establish experimental parameters dependency. The result is showing the complex dependence of samples cleanliness to each processing parameters like processing time, amplitude of oscillations, frequency of oscillations, process fluid parameters, instrumental medium, etc. Between this parameters although the most important successively the amplitude of oscillations, the frequency of oscillations the processing medium and the processing fluid depending to his considered composition, the optimal processing time can be reach only by complex combination of all this parameters every of them carry an amplify coefficient. Low frequency oscillations can be used to monitor and optimize washing and cleaning operations of paints and rusts contaminations. That guarantees process automation, its effectiveness for a large industrial application.

scholarly journals RESEARCH OF VIBRATION MACHINES DYNAMICS FOR PRODUCT SURFACES PROCESSING BY MATHEMATICAL MODELING

2020 ◽  
pp. 35-43
Author(s):  
Volodymyr Topilnytskyy ◽  
Yaroslav Kusyi ◽  
Dariya Rebot
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Surface Treatment ◽  
Lagrange Equation ◽  
The Body ◽  
Technological Problem ◽  
Surface Processing ◽  
Approximate Methods ◽  
Vibration Machine ◽  
Working Chamber

The article describes the methodology for the study of the dynamics of vibrating machines for surface processing of products by mathematical modeling, which is presented in four main stages. The first stage: analysis of classes of vibrating machines for surface treatment of products, choice of basic for solving the technological problem, project of a unified calculation scheme of the machine. The second stage: development of a nonlinear mathematical model for describing the dynamics of the vibration machine working body and its filling, development of elements of automated calculations of the machine. The third stage: the study of the influence of the parameters of the vibrating machine, product sets and tools (with their various combinations) on the factors of the intensity of products surface processing. The fourth stage: recommendations for choosing vibrating machine parameters and machining bodies that will maximize the processing performance of products with the selected intensity criterion. A mathematical model for describing the motion of a vibrating machine for surface treatment of articles by a set of unrelated bodies of small size is created. It has two unbalance units that generate oscillations of its working body and a spring suspension-mounting of the working chamber (container). The model is parametric and nonlinear, incorporating key dynamic, kinematic and geometric parameters of the vibrating machine in symbolic format. It is constructed by: descriptions of the plane-parallel movement of the mechanical system, the rotational motion of the material point and the body; second-order Lagrange equation; asymptotic (approximate) methods of nonlinear mechanics. With the help of the model it is possible: to describe the oscillatory movement of the working chamber (container) of the vibrating machine; to study the influence of the machine parameters on the efficiency of performance of the set technological task, the conditions of occurrence of non-stationary modes of operation of the vibrating machine and the ways of their regulation.

Mathematical Models of Control Systems of Angular Speed of Steam Turbines for Diagnostic Tests of Automatic and Mechatronic Devices

2013 ◽  
Vol 198 ◽  
pp. 519-524
Author(s):  
Grzegorz Redlarski ◽  
Janusz Piechocki ◽  
Mariusz Dąbkowski
Keyword(s):  
Angular Velocity ◽  
Power System ◽  
Control Systems ◽  
Working Conditions ◽  
Diagnostic Tests ◽  
Angular Acceleration ◽  
Angular Speed ◽  
Physical Parameters ◽  
Steam Turbines ◽  
Parallel Operation

In many automatics and mechatronics systems accurate modeling of several physical processes is needed. In power system, one of these is the process of control of angular velocity of power blocks during their connection to parallel operation. This process is extremely dynamic and the response of control system results from continuous changes in many physical parameters (temperature, pressure and flow of the working medium, etc.). An accuracy of modeling this process influences int. al. on: quality of the automatic synchronizer diagnostic tests in the laboratory, as well as the possibility of evaluation of prospects for connection process in the power system, without the automatic synchronizer [. Automatics systems used for research and diagnosis of automatic synchronizers are known in the literature as and simulators [2, . To impose similar to real working conditions, it is required to implement an appropriate models of control systems. One of such models, representative for the larger population of objects, is model of control systems of angular velocity. Currently used models, e.g. [3, 4, 5, , allow to approximate the response of real object, or to impose higher restricted conditions of work, for example: related to the angular acceleration dω/dt, the size of overshoots and decay time of transitional characteristics, while accurate modeling the real working conditions using them is not possible. Furthermore, their use requires knowledge of the (often difficult to access) object parameters and time-consuming selection of manual procedure of certain substitute settings, occurring in these models. To eliminate inconveniences mentioned above, in the paper the proposal and mathematical modeling procedure is presented, which allow to obtain much more accurate transitional characteristics of real objects.

Reduction of Torsional Vibration in Resonance Phenomena for Tractor Power Take-Off Drivelines Using Torsional Damper

2021 ◽  
Vol 64 (2) ◽  
pp. 365-376
Author(s):  
Da-Vin Ahn ◽  
In-Kyung Shin ◽  
Jooseon Oh ◽  
Woo-Jin Chung ◽  
Hyun-Woo Han ◽  
...  
Keyword(s):  
Angular Velocity ◽  
Torsional Vibration ◽  
Simulation Software ◽  
Drive Shaft ◽  
Torsional Stiffness ◽  
List Type ◽  
Two Stage ◽  
Mass Moment ◽  
Simulation Results ◽  
Agricultural Tractors

HighlightsRattling of tractor power take-off drivelines can be detrimental to operators.A novel driveline model, which includes a torsional damper, was constructed.The behavior of the model was validated against that of an actual tractor driveline.The validated model was used to determine the optimal torsional damper parameters.These optimal parameters were validated by laboratory tests.Abstract. Rattle noise and high levels of vibration in agricultural tractors lower the productivity of the operators and may cause serious health issues in them. This study examined a method for preventing resonance and reducing the torsional vibration that causes rattling in tractor power take-off (PTO) drivelines in the idle state using a two-stage torsional damper. The PTO driveline was simplified to a 6-DOF model based on the principle of equivalent mass moment of inertia using commercial simulation software. The variations in the angular velocity of the PTO drive shaft in an actual tractor were measured and compared to the simulation results using a single-stage torsional damper to validate the model. Using this validated PTO driveline model, the pre spring of a two-stage torsional damper was investigated to determine its optimal torsional stiffness to minimize torsional vibration. The simulation results showed that the variations in the angular velocity of the PTO drive shaft decreased as the torsional stiffness of the pre spring decreased; accordingly, an appropriate torsional stiffness reduced the variation in the angular velocity delivered to the PTO drive shaft. The optimal torsional stiffness of the pre spring was determined by considering the manufacturing limitations of the torsional damper and the magnitude of the input engine torque. A pre spring with this optimal torsional stiffness was installed on an actual PTO driveline to measure the angular velocity transmissibility, which was the ratio of the variation in the angular velocity of the engine flywheel to the variation in the angular velocity of the PTO drive shaft, and the results were compared with those of the simulation. When the angular velocity of the engine was 850 rpm, the angular velocity transmissibility of the PTO drive shaft was 0.4 in the actual test, similar to the value of 0.29 obtained using the simulation. Thus, the simulation-optimized pre spring was able to avoid the resonance domain, while considerably reducing the torsional vibration that leads to rattling. The results of this study support the safe operation of agricultural tractors and guide the evaluation of torsional damper configurations of different vehicles. Keywords: PTO driveline, Resonance, Simulation model, Torsional damper, Torsional vibration, Tractor rattle.

scholarly journals Dynamic Model and Quantitative Analysis of Stick-Slip Vibration in Horizontal Well

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Baojin Wang ◽  
Zhongyang Wang ◽  
Fushen Ren
Keyword(s):  
Angular Velocity ◽  
Horizontal Well ◽  
Angular Speed ◽  
Stick Slip ◽  
Rock Interaction ◽  
Axial Excitation ◽  
Nonlinear Motion ◽  
Fluctuation Amplitude ◽  
Torsional Excitation ◽  
Observation Results

Stick-slip is very harmful to the service life of drillstring. The extended Hamilton principle is applied in the paper. Then, finite element method (FEM) is employed to describe the model. The drillstring-borehole impact and friction, fluid-structure interaction, bit-rock interaction, and gravity are considered in this model. The influence of axial and torsional excitation on stick-slip is analyzed. The nonlinear motion predicted by the model is consistent with the observation results in the experiments. The research shows that the fluctuation amplitude of the bit angular velocity also increases along with the increase of driving angular velocity (torsional excitation). However, both the ratio of the maximum angular velocity of the stick-slip vibration and the fluctuation of the angular velocity are continuously reduced. Meanwhile, the strength of the stick-slip vibration has a tendency to slow down. As the axial load (axial excitation) increases, the fluctuation of the maximum angular speed of the stick-slip vibration does not change significantly, but the smaller load causes a smaller stick duration.

Studies of the Modelling Accuracy of Steam Turbine Control Systems for Diagnostic Tests of Automatic Synchronizers

2013 ◽  
Vol 199 ◽  
pp. 61-66
Author(s):  
Grzegorz Redlarski ◽  
Janusz Piechocki ◽  
Mariusz Dąbkowski
Keyword(s):  
Angular Velocity ◽  
Control Systems ◽  
Working Conditions ◽  
Synchronous Generator ◽  
Angular Speed ◽  
Velocity Control ◽  
Reliable Operation ◽  
Relevant Field ◽  
The Impact ◽  
Selection Of

One of the important factors that affect the reliable operation of the power system and the rapid restitution after disaster is a quick and effective combining synchronous electric power facilities to operate in parallel [. Hence, diagnostics of automatic synchronizers at every stage of their life, from building a prototype, through the whole life, until removing such devices from the operation, is an extremely important and responsible activity. In ordinary practice, this action is performed by dedicated test of mechatronics systems, called simulators [2, , in close to real - or even more restricted - conditions. One of the major limitations in the relevant field undoubtedly concerns the selection of an appropriate structure and implementation of models of the angular velocity control systems involved in the process of connection. These models must be simple enough to allow computation with a frequency of kHz, and, at the same time, developed enough to be able to form diverse and close to real working conditions. For these reasons, classical approach is not possible, allowing the use of well-known Parks model [ of the synchronous generator and the complex - and often nonlinear [. Hence, considered above-mentioned requirements and indicated constraints, to test the automatic synchronizer the designers of mechatronics systems use a number of simplifications during modeling of the angular speed control systems [. However, models are not detailed enough to study the impact of changes in the shape of relevant characteristics under the influence of changes the angle of phase discrepancy in the process of connecting. Hence, this paper presents the results of the research of the currently used method of modeling the most commonly used control systems of angular velocity, in the respective systems.

Design Principles of a Four Bar Crank Continuously Variable Transmission

2008 ◽  
Author(s):  
W. Allan Yates
Keyword(s):  
Design Principles ◽  
Angular Speed ◽  
Continuously Variable Transmission ◽  
Drive Shaft ◽  
The Other ◽  
Energy Utilization ◽  
Link Length ◽  
Peak Efficiency ◽  
Vector Solution ◽  
Variable Transmission

Continuously Variable Transmissions (CVTs) can be used to optimize the energy utilization of systems by allowing the prime mover to operate at speeds of peak efficiency while allowing the driven components to move at desired speeds. A CVT saves energy by reducing the off-peak efficiency of a system. The basic design principles of a Continuously Variable Transmission composed of a sequence of 4-bar cranks are discussed. The vector solution for 4-bar cranks is iteratively solved for a crank sequence to illustrate how different output speeds can be obtained from the same input speed. This is accomplished by varying the length of the connecting link on each 4-bar crank in the sequence. Solutions are plotted. Each 4-bar crank is located on the same drive shaft and the same driven shaft. Each crank has the same drive link length and the same driven crank length. A one way clutch located on each driven link transmits motion to the driven shaft. The cranks are positioned so that they are out of phase with each other so that only the fastest crank transmits motion, over-running all the other cranks. For a given length of the connecting link, the motion of the driven shaft is not uniform. This is due to the 4-bar crank transmission of peak speed. As one 4-bar crank moves, at some point the angular speed of the driven link will overtake the speed of the driven link on the other crank sets. It will then peak and then slow to be overtaken by another crank-set. The more evenly distributed crank-sets used the more uniform the motion will be. In this sense, a given length of connecting link for the sequence of cranks will generate an average drive shaft speed. If the length of the connecting link in a 4-bar crank is changed, a change in motion of the driven shaft will occur. By changing the length of the connecting link on the 4-bar cranks, the average speed of the driven shaft can be changed. A CVT is made by infinitesimally changing the length of the connecting link. This infinitesimal change is easily accomplished via standard components such as pneumatic or hydraulic cylinders or various other means.

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