scholarly journals Calculation of the movement trajectory of the grain mass in the field stripper

2020 ◽  
Vol 210 ◽  
pp. 08015
Author(s):  
Andrey Matrosov ◽  
Daria Nizhnik ◽  
Ivan Panfilov ◽  
Viktor Pakhomov ◽  
Irina Serebryanaya ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Finite Volumes ◽  
Movement Trajectory ◽  
Kinematic Parameters ◽  
Air Mass ◽  
Second Stage ◽  
Upper Deck

The work is devoted to the study of the dynamics of the grain mass in a field stripper for grain separation. At the first stage, a model of the movement of the air mass in the considered installation is built and based on a mathematical model that takes into account the turbulence of the movement of the air mass, using the method of finite volumes in the ANSYS package, the field of velocities and pressures is calculated. At the second stage, the movement of a fragment of the grain mass in this flow is considered, its trajectory is built taking into account the interaction with the upper deck of the installation. The performed calculations allow us to choose rational geometric and kinematic parameters at which no stagnant zones appear in the chamber, the grain mass interacts with the upper one, which contributes to the release of grain in the installation chamber.

THE HEAP PARTS MOVEMENT ON THE SHAREBOARD SURFACE OF THE POTATO HARVESTING MACHINE

2021 ◽  
Vol 14(63) (1) ◽  
pp. 127-140
Author(s):  
Serhii HRUSHETSKYI ◽  
Vitaly YAROPUD ◽  
Ihor KUPCHUK ◽  
Ruslana SEMENYSHENA
Keyword(s):  
Mathematical Model ◽  
Experimental Studies ◽  
Separation Process ◽  
Kinematic Parameters ◽  
Quality Performance ◽  
Machine Operation ◽  
Degree Of Damage ◽  
Total Capacity ◽  
Comparison Of The Results

The article is devoted to the problem of the reduction of tubers mechanical damages while providing qualitative indicators of the potato heap separation process. Theoretical and experimental dependences of the influence of design and kinematic parameters of the machine operation on the quality performance are obtained. Within the field of experimental studies, a field installation was made to investigate the potato harvester as a whole on the efficiency of separation, the degree of damage, the magnitude of losses and the total capacity for aggregation. Comparison of the results of theoretical and experimental studies showed that the developed mathematical model of the process of separation of potato heap is adequate.

scholarly journals Analysis of Platform Leveling Systems for Tracked Feller-Buncher Machines

Inventions ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 96
Author(s):  
Andronov Alexandr ◽  
Bacherikov Ivan ◽  
Zverev Igor
Keyword(s):  
Mathematical Model ◽  
Center Of Mass ◽  
Slope Angle ◽  
Hydraulic Cylinder ◽  
Second Stage ◽  
Modeling Methods ◽  
The Third ◽  
Support Reaction ◽  
Third Stage ◽  
The Stability

The study was devoted to the analysis of feller buncher platform leveling systems. The widespread use of these systems in the design of modern feller-buncher machines makes the study relevant to assess operational efficiency. The analysis was conducted in five stages using analytical and stochastic mathematical modeling methods. In the first stage, the existing layouts of alignment systems were analyzed from the position of force on the hydraulic cylinder rods of the platform tilt drive. The three-cylinder layout scheme, where the force on the hydraulic cylinder rod was 50…60% less than that on the two-cylinder layout, appeared to be the most expedient. In the second stage, a mathematical model for determining changes in the position of the center of mass of the feller-buncher depending on the inclination angle of the platform was derived. In the third stage, a mathematical model was derived for determining the limiting angle of slope of the terrain when the feller buncher moved up the slope. For this purpose, two calculation schemes were considered when the machine moved up the slope without and with a tilted platform. Zero support reaction on the front roller was taken as the stability criterion. In the fourth stage, a mathematical model for determining the limiting angle of slope of the terrain during the roll of the feller-buncher machine was obtained. In the fifth stage, the efficiency of the application of leveling systems was evaluated. A graph of the dependence of changes in the terrain slope angle on the platform slope angle was plotted, and a regression dependence for an approximate estimate was obtained. A regression analysis was also carried out, and dependencies were obtained to determine the weight of a feller-buncher with a leveling system and the added pressure on the ground caused by the increase in the weight of the base machine. The analysis of platform leveling systems showed the effectiveness of their application in the designs of feller-buncher machines, as it allows the machines to work on slopes with an inclination of 50…60% more than without them.

scholarly journals Study on the Mathematical Model of Vacuum Breaker Valve for Large Air Mass Conditions

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1358
Author(s):  
Zhang ◽  
Fan ◽  
Yu ◽  
Zhang ◽  
Lv ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Theoretical Basis ◽  
Isothermal Process ◽  
Air Mass ◽  
Protection Scheme ◽  
Calculation Results ◽  
Air Valve ◽  
The Mathematical Model ◽  
Valve Model ◽  
Derivation Process

The mathematical model of vacuum breaker valve is significant to the protection scheme. The more accurate the vacuum breaker valve model, the more reliable the calculation results. In this study, the application conditions of the air valve model are analyzed according to the assumptions used in the derivation, and the contradictions between these assumptions are proposed. Then, according to the different working characteristics between the vacuum breaker valve on the siphon outlet pipe and the air valve, the vacuum breaker valve model is deduced based on the modified assumptions. In the derivation process, the thermodynamic change of the gas in the vacuum breaker valve is assumed to follow the isentropic process rather than an isothermal process, and the water level in the vacuum breaker valve is considered to be changeable. An engineering case is introduced, and the results calculated according to the vacuum breaker valve model are compared with those resulting from the air valve model. The results indicate that the vacuum breaker valve model is suitable for large air mass conditions and can provide a theoretical basis for the numerical simulation and settings of vacuum breaker valves.

Determination of Kinematic Parameters of Rotary Transmission Tooled with Hydraulic Cylinders

2015 ◽  
Vol 770 ◽  
pp. 407-413
Author(s):  
M.Yu. Blashchuk ◽  
T.S. Kust ◽  
M.V. Dubrovskiy ◽  
V.G. Lizunkov
Keyword(s):  
Mathematical Model ◽  
Kinematic Parameters ◽  
Output Element ◽  
Hydraulic Cylinders ◽  
Pumping Unit ◽  
Element Movement ◽  
Design Factors

The paper considers mathematical model developed by the authors which determines the relation of design factors of transmission tooled with hydraulic cylinders to kinematic parameters of output element movement. The paper also provides description of methods to determine pumping unit efficiency for rotary transmission tooled with hydraulic cylinders.

scholarly journals Analysis of the error of the optical material removal function in a multivariate mathematical model for controlling the shaping processlarge optical parts

2021 ◽  
pp. 85-94
Keyword(s):  
Mathematical Model ◽  
Material Removal ◽  
Optical Material ◽  
Kinematic Parameters ◽  
Full Size ◽  
Optical Surfaces ◽  
Physicochemical Features ◽  
Processing Zone ◽  
Func Tion ◽  
Grinding And Polishing

The features of technological processes for controlling the shaping of the optical surfaces of large-sized flat parts at the stages of grinding and polishing on modern machines of continu-ous shaping with a full-size tool.The substantiation of the structure of a multifactorial mathe-matical model of the processes of grinding and polishing of flat optical surfaces is given on the basis of studying the laws of motion of actuators and the processing zone of optical machines of continuous shaping with a full-size tool. The analysis of the influence of technological fac-tors and physicochemical features of the processes of processing surfaces of flat optical parts on the function of removing the optical material of a model of chemical mechanical polishing (CMP) is presented. The analysis of the study of the error of the optical material removal func-tion of the presented multivariate mathematical model with the recommendation for fixing cer-tain values of the main kinematic parameters of machine equipment is carried out.

scholarly journals MODELING THE OPERATION OF A RECUPERATIVE SPRING-HYDRAULIC FIFTH-WHEEL COUPLING LOCATED IN THE SEMITRAILER OF LUMBER TRUCK

2021 ◽  
Vol 11 (2) ◽  
pp. 133-148
Author(s):  
Valeriy Posmetev ◽  
Vadim Nikonov ◽  
Viktor Posmetev ◽  
Vladimir Zelikov
Keyword(s):  
Mathematical Model ◽  
Computer Program ◽  
Front Part ◽  
Preliminary Assessment ◽  
Second Stage ◽  
Longitudinal Acceleration ◽  
Hydraulic Cylinders ◽  
Inner Diameter ◽  
The Given ◽  
Optimal Diameter

The substantiation of the necessity of using timber trucks, consisting of timber tractors with semi-trailers, when transporting timber, is given. Attention is focused on improving the efficiency of the functioning of log trucks by con-structive improvement of the fifth-wheel couplings used in them. The analysis of scientific works of foreign scientists engaged in the study of the influence of fifth- wheel coupling on the efficiency of log trucks is carried out. A promising scheme of a recuperative spring-hydraulic fifth-wheel coupling, located in the front part of the semi-trailer frame of a timber tractor, is proposed, which has significant advantages in comparison with other similar devices. At the first stage, a mathematical model of the proposed fifth-wheel coupling was developed; at the second stage, a computer program for a preliminary assessment of the efficiency of the functioning of a timber tractor with a semitrailer equipped with a recuperative spring-hydraulic fifth-wheel coupling is made. The dependences of the change in the average values of the recuperative power and longitudinal acceleration of the trailer relative to the timber tractor on the inner diameter of the hydraulic cylinders of the recuperative device, the mass of the semi-trailer and the frequency of braking and accelera-tion of the timber road train are obtained. It was revealed that the optimal diameter of the hydraulic cylinders of the recuperative device for the given conditions, providing the maximum recuperative power, should be in the range of 50-60 mm. It was found that with an increase in the mass of a semitrailer of a logging tractor, as well as with an increase in the frequency of braking and acceleration, an increase in the recovered power is observed

Experimental investigation for better relative localization of a mobile robot using Taguchi method

Robotica ◽  
2014 ◽  
Vol 33 (7) ◽  
pp. 1415-1423
Author(s):  
T. Mathavaraj Ravikumar ◽  
R. Saravanan
Keyword(s):  
Mathematical Model ◽  
Taguchi Method ◽  
Mobile Robot ◽  
Mobile Robotics ◽  
Kinematic Parameters ◽  
Absolute Position ◽  
Relative Localization ◽  
Wheeled Robot ◽  
Position And Orientation

SUMMARYThe positioning of a wheeled robot is an imperative manipulation problem in mobile robotics. Odometry is a familiar method for determining the relative position of a mobile robot. It comprises the detection of a set of kinematic parameters that permit reconstructing the robot's absolute position and orientation starting from the wheels' encoder measurements. This paper deals with the determination of better relative localization of a mobile robot by means of odometry by considering the influence of parameters namely total weight, speed, diameter of wheel, and width of wheel. Experiments have been conducted based on L9 orthogonal array suggested in Taguchi method to obtain the optimum condition. A mathematical model has also been developed for the mobile robot with the help of MINITAB software.

scholarly journals Normal Incidence of Sound Transmission Loss of a Double-Leaf Partition Inserted with a Microperforated Panel

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
A. Putra ◽  
A. Y. Ismail ◽  
R. Ramlan ◽  
Md. R. Ayob ◽  
M. S. Py
Keyword(s):  
Mathematical Model ◽  
Transmission Loss ◽  
Low Frequency ◽  
Sound Transmission ◽  
Normal Incidence ◽  
Sound Transmission Loss ◽  
Engineering Structures ◽  
Air Mass ◽  
Noise Barrier ◽  
The Mathematical Model

A double-leaf partition in engineering structures has been widely applied for its advantages, that is, in terms of its mechanical strength as well as its lightweight property. In noise control, the double-leaf also serves as an effective noise barrier. Unfortunately at low frequency, the sound transmission loss reduces significantly due to the coupling between the panels and the air between them. This paper studies the effect of a microperforated panel (MPP) inserted inside a double-leaf partition on the sound transmission loss performance of the system. The MPP insertion is proposed to provide a hygienic double-leaf noise insulator replacing the classical abrasive porous materials between the panels. It is found that the transmission loss improves at the troublesome mass-air-mass resonant frequency if the MPP is located closer to the solid panel. The mathematical model is derived for normal incidence of acoustic loading.

Kinematic Optimization of a Redundantly Actuated Parallel Mechanism for Maximizing Stiffness and Workspace Using Taguchi Method

2010 ◽  
Vol 6 (1) ◽  
Author(s):  
Hyunpyo Shin ◽  
Sungchul Lee ◽  
Woosung In ◽  
Jay I. Jeong ◽  
Jongwon Kim
Keyword(s):  
Taguchi Method ◽  
Parallel Mechanism ◽  
Optimization Procedure ◽  
Kinematic Parameter ◽  
Response Analysis ◽  
Kinematic Parameters ◽  
Stiffness Analysis ◽  
Second Stage ◽  
Workspace Analysis ◽  
Redundantly Actuated

We present an optimization procedure that uses the Taguchi method to maximize the mean stiffness and workspace of a redundantly actuated parallel mechanism at the same time. The Taguchi method is used to separate the more influential and controllable variables from the less influential ones among kinematic parameters in workspace analysis and stiffness analysis. In the first stage of optimization, the number of experimental variables is reduced by the response analysis. Quasi-optimal kinematic parameter group is obtained in the second stage of optimization after the response analysis. As a validation of the suggested procedure, the kinematic parameters of a planar 2-DOF parallel manipulator are optimized, which optimization procedure is used to investigate the optimal kinematic parameter groups between the length of the link and the stiffness.

Predictions of ice-cover development in streams and its effect on dissolved oxygen modelling

1979 ◽  
Vol 6 (2) ◽  
pp. 197-207 ◽  
Author(s):  
E. McBean ◽  
G. Farquhar ◽  
N. Kouwen ◽  
O. Dubek
Keyword(s):  
Mathematical Model ◽  
Water Quality ◽  
Dissolved Oxygen ◽  
Prediction Model ◽  
Data Input ◽  
Quality Model ◽  
Two Stage ◽  
Second Stage ◽  
Series Of Experiments ◽  
Ice Edge

A two-stage mathematical model is developed for predicting dissolved oxygen levels in ice-covered rivers. The first stage of the model is a prediction model for ice-edge progression as a function of time, and the second stage consists of an extrapolation of a widely used 'summer condition' water-quality model. The results of a series of experiments, both field and laboratory-based, which served as data input generators and calibration testing of the model, are provided.Briefcase-study applications of elements of the model to the Speed River and to the Saint John River are included.

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