scholarly journals The Applied model of grinding a spherical solid particle with a direct impact on a non-deformable flat surface

2020 ◽  
pp. 32-42
Author(s):  
G A Guryanov ◽  
B M Abdeev
Keyword(s):  
Mathematical Model ◽  
Flat Surface ◽  
Spherical Shape ◽  
Grinding Process ◽  
Direct Impact ◽  
Applied Model ◽  
Technical Theory ◽  
Force Contact ◽  
Breakage Mechanism

A grinding process using a free impact breakage mechanism is used in industries. In order to make calculations, predict grinding results, and evaluate mills functioning, it is necessary to assess the parameters of the grinding process and interrelations between the process parameters, mills parameters and materials properties, i.e. it is necessary to use an adequate mechanical-mathematical model of the process. However it is difficult to model due to some phenomena occurring in this process. Nowadays, various researchers have established the basis for the structure of the grinding process, but the application of the existing hypotheses and methods to evaluate the grinding process is quite difficult. This paper solves the problem of a spherical shape particle impacting an absolutely rigid half-space. It proposes a refined mechanical and mathematical model describing the process of destruction of the particle using the free direct impact breakage mechanism on an absolutely rigid, stationary, and flat surface. By using the Hertz-Staerman's classical analytical dependencies on the force contact interaction of the spherical bodies and the technical theory of the longitudinal waves’ propagation in the elastic continuous medium, we obtained a new refined solution of the applied dynamic problem related to a direct impact of a ball simulating a particle of a feeding material (an absolutely rigid surface simulating the working body of the mill) taking into account local physically linear deformations, the time parameter and radial particle size. The improved theoretical model of the spherical particle destruction was brought to applicable analytical calculations, tested and illustrated by a numerical example. It made it possible to describe the fracture of the material particles, predict the result and calculate the grinding process depending on its parameters providing the required quality of grinding by regulating and selecting characteristics, designing and selecting the grinding equipment, and modeling the grinding process using the free impact breakage mechanism.

Study on Grinding Technology of Granite Thin Slab

2012 ◽  
Vol 500 ◽  
pp. 281-286
Author(s):  
Xue Hua Wei ◽  
Jin Sheng Zhang ◽  
Bo Huang ◽  
Zhi Wang
Keyword(s):  
Mathematical Model ◽  
Process Parameters ◽  
Fracture Criterion ◽  
Critical Thickness ◽  
Grinding Process ◽  
Thin Slab ◽  
Set Up ◽  
Stone Industry ◽  
The Mathematical Model

With the development of economical society and the stone industry, the product of granite thin slab becomes a trend, and gets the welcome of people. The grinding technology influences the quality of granite thin slab. This paper first introduced the situation of the grinding technology of granite thin slab, analyzed the mechanism of the grinding process of granite thin slab and fractured problem by observing the fractured granite thin slab. Then, based on the Hoek-Brown criterion, we researched the fracture criterion and the critical thickness of granite thin slab when grinding. Finally, we set up the fracture criterion of the granite thin slab and built the mathematical model between the thickness of the granite thin slab and grinding process parameters. According to the thickness of the granite thin slab, grinding process parameters can be formulated, in order to ensure the granite thin slab no fractured.

The Analysis of the Temperature Influence on the Processing Precision in Centerless Grinding Machines

2014 ◽  
Vol 659 ◽  
pp. 331-336
Author(s):  
Adrian Cernaianu
Keyword(s):  
Measurement Accuracy ◽  
Elastic System ◽  
Grinding Process ◽  
Direct Impact ◽  
Temperature Influence ◽  
Influence Of Temperature ◽  
Machined Parts ◽  
Centerless Grinding ◽  
Grinding Machines

In this paper it is presented an analysis regarding the influence of temperature from the chipping area, in the machining by centerless grinding with transversal feed. The temperature influences the machining precision, the additional loads of the machine – device – tool – part elastic system and the measurement accuracy. These influences have direct impact on the precision and quality of the machined parts executed using the centerless grinding process.

Multifactor mathematical model of criticality of welding process of products from aluminum- magnesium alloys

2020 ◽  
pp. 12-18
Author(s):  
F.A. Urazbahtin ◽  
A.YU. Urazbahtina
Keyword(s):  
Mathematical Model ◽  
Magnesium Alloy ◽  
Magnesium Alloys ◽  
Welding Process ◽  
Welding Equipment ◽  
Equipment Operation ◽  
Aluminum Magnesium Alloys ◽  
Aluminum Magnesium Alloy ◽  
Welding Materials

A multifactor mathematical model of the welding process of products from aluminum-magnesium alloys, consisting of 71 indicators that assess the quality of the weld, the welding process, costs, equipment operation and quality of the welded material. The model can be used to control and optimize the welding process of products from aluminum-magnesium alloys. Keywords welding, products, aluminum-magnesium alloy, indicators, process parameters, welding equipment, welding materials, electrode sharpening, lining [email protected]

Network analysis models – the secret for success

2004 ◽  
Vol 4 (5-6) ◽  
pp. 383-388
Author(s):  
D.M. Rogers
Keyword(s):  
Mathematical Model ◽  
Field Data ◽  
Essential Element ◽  
Distribution Networks ◽  
Automatic Calibration ◽  
Supply And Distribution ◽  
The World ◽  
Optimum Approach ◽  
Analysis Models

Water is a fundamental necessity of life. Yet water supply and distribution networks the world over are old and lacking in adequate maintenance. Consequently they often leak as much water as they deliver and provide an unacceptable quality of service to the customer. In certain parts of the world, water is available only for a few hours of the day. The solution is to build a mathematical model to simulate the operation of the real network in all of its key elements and apply it to optimise its operation. To be of value, the results of the model must be compared with field data. This process is known as calibration and is an essential element in the construction of an accurate model. This paper outlines the optimum approach to building and calibrating a mathematical model and how it can be applied to automatic calibration systems.

Numerical Simulation on Mold Electromagnetic Eccentric Stirring and Central Segregation of Round Bloom

2013 ◽  
Vol 652-654 ◽  
pp. 2450-2454
Author(s):  
Zhi Hong Zhang ◽  
Guo Guang Cheng
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Electromagnetic Stirring ◽  
Center Line ◽  
Central Segregation

The paper describes multi-section round bloom casting using external MEMS, equipped with max section D600mm and min D280mm mold, the center line of D280mm mold not coincident with the axis of stirrer coils. it is exist eccentric electromagnetic stirring of mold which section less than max D600mm, a mathematical model of MEMS has been established, the index of central segregation of D280mm macrostructure had decreased less than 1.12 by optimized parameters of electromagnetic stirring and SEN immerse depth, in the end, the quality of round bloom had improved.

Influence of Tooth Errors and Truing Principles of Grinding Wheel Abrasion for Machining Arc Enveloping Worm

2013 ◽  
Vol 652-654 ◽  
pp. 2153-2158
Author(s):  
Wu Ji Jiang ◽  
Jing Wei
Keyword(s):  
Mathematical Model ◽  
Case Studies ◽  
High Precision ◽  
High Performance ◽  
New Method ◽  
Grinding Wheel ◽  
Grinding Process ◽  
The Mathematical Model

Controlling the tooth errors induced by the variation of diameter of grinding wheel is the key problem in the process of ZC1 worm grinding. In this paper, the influence of tooth errors by d1, m and z1 as the grinding wheel diameter changes are analyzed based on the mathematical model of the grinding process. A new mathematical model and truing principle for the grinding wheel of ZC1 worm is presented. The shape grinding wheel truing of ZC1 worm is carried out according to the model. The validity and feasibility of the mathematical model is proved by case studies. The mathematical model presented in this paper provides a new method for reducing the tooth errors of ZC1 worm and it can meet the high-performance and high-precision requirements of ZC1 worm grinding.

scholarly journals Effects of Field Processing of Sorghum Grain on Popping Traits

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 839
Author(s):  
Mitchell Kent ◽  
William Rooney
Keyword(s):  
Impact Force ◽  
Grain Sorghum ◽  
Expansion Ratio ◽  
Direct Impact ◽  
Order Of Magnitude ◽  
Rubber Belt ◽  
Sorghum Grain ◽  
Harvest Moisture ◽  
Quality Measurements

Interest in the use of popped sorghum in food products has resulted in a niche market for sorghum hybrids with high popping quality but little work has been done to assess the relative effects of field processing methods of grain on popping quality. This study evaluated the relative effects of harvest moisture and threshing methods on the popping quality of sorghum grain. A grain sorghum hybrid with good popping quality was produced during two different years in Texas wherein it was harvested at two moisture levels (low and high) and grain was removed from panicles using five different threshing methods (hand, rubber belt, metal brushes and two metal concave bar systems). Years, harvest moisture content and threshing method influenced all three popping quality measurements (popping efficacy, expansion ratio and flake size), but threshing method had an order of magnitude larger effect than either moisture level or year. While many of the interactions were significant, they did not influence the general trends observed. As such, the threshing methods with less direct impact force on the grain (hand and rubber belt) had higher popping quality than those samples threshed with greater impact force on the grain (metal-based systems). The popping quality differences between threshing system are likely due to a reduction in kernel integrity caused by the impacts to the kernel that occurred while threshing the grain. The results herein indicate that field processing of the grain, notably threshing method has significant impacts on the popping quality and should be taken into consideration when grain sorghum is harvested for popping purposes.

Einfluss der Abrichtgrößen beim Schleifen*/Influence of dressing parameters on the grinding process - Systematic research of dressing parameters on workpiece roughness and surface integrity

2016 ◽  
Vol 106 (01-02) ◽  
pp. 44-50
Author(s):  
T. Lierse ◽  
B. Karpuschewski ◽  
T. R. Kaul
Keyword(s):  
Aluminum Oxide ◽  
Surface Integrity ◽  
Cvd Diamond ◽  
Grinding Wheel ◽  
Systematic Research ◽  
Grinding Process ◽  
Wheel Topography ◽  
Grinding Wheel Topography

Dieser Beitrag zeigt, dass die durch die Abrichtparameter erzeugte Schleifscheibentopographie nicht nur die Oberflächengüte des Werkstücks, sondern auch dessen Eigenspannungszustand in der Werkstückrandzone in weiten Grenzen verändert. Die Untersuchungen zum Abrichten von Korundschleifscheiben mit einer CVD-Diamantformrolle stellen den Zusammenhang zwischen dem Abrichten unterschiedlicher Schleifscheiben zur Bauteilqualität in Form der Oberflächenrautiefe und randzonennahen Eigenspannungen her.   The quality of the workpiece rim is changed by every grinding process. The grinding wheel topography created by the dressing process has not only influence on the workpiece roughness but also on the surface integrity. The pointed research using aluminum oxide abrasive wheels dressed by CVD diamond dressing discs shows a correlation between the dressing parameters, the workpiece roughness and the surface integrity.

Implementation of Digital Technologies Into the Educational Process

2021 ◽  
Vol 15 ◽  
pp. 385-391
Author(s):  
Eva Panulinova ◽  
Slavka Harabinova ◽  
Renata Baskova
Keyword(s):  
Quality Of Life ◽  
Construction Industry ◽  
Social Life ◽  
Civil Engineering ◽  
Digital Technologies ◽  
Educational Process ◽  
Skills Development ◽  
Direct Impact ◽  
Planning Implementation

Revolutionary changes in society are linked to digital technologies and affect all areas of social life, not excluding construction industry. This requires not only knowledge reform, but above all skills reform. The current demand of practice is to increase the knowledge and competences of graduates of civil engineering faculties in the field of introduction and use of digital technologies in the process of planning, implementation, and maintenance of buildings, as well as to support the skills development of civil engineers in teamwork while using BIM technologies. The presented, currently implemented project contributes to meeting the above-described Practice Needs. The expected direct impact of the project is to increase the competitiveness, employability, and quality of life of graduates entering practice.

scholarly journals INCREASING THE COMPETITIVENESS OF INSURANCE COMPANY PRODUCTS AND SERVICES USING ECONOMIC AND MATHEMATICAL MODELING METHODS

2021 ◽  
Author(s):  
Mykhailo Demydenko ◽  
Ihor Pistunov
Keyword(s):  
Mathematical Model ◽  
Social Activity ◽  
Insurance Companies ◽  
Comprehensive System ◽  
Insurance Company ◽  
Competitive Advantages ◽  
Insurance Policy ◽  
Insurance Policies ◽  
The Impact

The competitiveness of an insurance company depends on the competitiveness of the products and services it introduces in the market. The competitive advantages of the insurance company are expressed in the attractiveness and competitiveness of insurance policies. An economic and mathematical model of increasing the competitiveness of the insurance company is proposed, which allows to calculate the integrated indicator of competitiveness of the insurance policy based on a comprehensive system of indicators characterizing the reliability of the insurance company, quality of its services, competitiveness, social activity. To analyze the impact of these indicators on the competitiveness of the insurance policy and identify areas for improving the efficiency and competitiveness of the insurance company. The competitiveness of an insurance company depends on the competitiveness of the products and services it introduces in the market. The assessment of the quality of insurance company services is compliance with the needs, requirements, and insurance interests of customers. This assessment is performed each time an individual client chooses to cooperate with an insurance company that meets his insurance interests and wishes. Therefore, the overall competitiveness of the enterprise depends on the competitiveness of products and services offered on the market. The competitive advantages of the insurance company are expressed in the attractiveness and competitiveness of insurance policies. The insurance market in recent years has shown consistently high growth, which makes it attractive for doing business. In these conditions, the task of modeling the activities of the insurance company in a highly competitive market environment becomes relevant. A mathematical model of increasing the competitiveness of the insurance company is proposed, which allows to calculate the integrated indicator of competitiveness of the insurance policy based on a comprehensive system of indicators characterizing the reliability of the insurance company, quality of its services, competitiveness, social activity. With the proposed model, insurance companies can objectively assess their weaknesses and strengths to ensure continuous growth and decent competition in a competitive market environment. The model allows you to select performance indicators and perform modeling and determine the consequences of changes in this indicator, analyze the impact of these indicators on the competitiveness of insurance policies and identify areas for improving the efficiency and competitiveness of the insurance company. By conducting such experiments, insurance companies can make more informed choices and decisions, analyze areas of competitiveness, and more efficiently allocate resources.

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