DETERMINATION OF PARAMETERS OF THE WORKING IMPLEMENT OF A ROOT CROPPER

2021 ◽  
pp. 42-48
Author(s):  
MIKHAIL G. ZAGORUIKO ◽  
◽  
VALENTIN V. VASILCHIKOV ◽  
YURI V. KATAEV ◽  
ANZHELA K. MAMAKHAY3 ◽  
...  
Keyword(s):  
Physical And Mechanical Properties ◽  
Strength Characteristics ◽  
Design Parameters ◽  
Experiment Planning ◽  
High Quality ◽  
Strength Assessment ◽  
Processed Material ◽  
Design Selection ◽  
Determination Of Parameters

The main condition for feed preparation is to ensure the high quality of the finished product. At the sametime, it is necessary to increase the efficiency and durability of the feed chopper by optimizing its design parameters,taking into account the physical and mechanical properties of the processed material. The authors studied the technologicalprinciple of crushing root and tuber crops. The paper considers the operation of an industrial rotary feed chopper whenprocessing beets and carrots. The experiment planning method is applied. The strength characteristics of the grinderelements were checked during design (selection of the shape and sharpening angle of knives) and verificationcalculations for strength (assessment of the strength characteristics of knives). The authors show the influence of the main geometric parameters of the working implement of the grinder – the knife inclination and the sharpeningangle of the knives – on the preparation of high-quality feed. It was revealed that the sharpening angle of the grinderknives should be calculated depending on the friction coefficient of the initial material against the grinder body, aswell as the type and properties of the supplied material. Based on the data obtained during the laboratory experimentand simulation modeling, in order to achieve greater versatility with the feed chopper, a combined shape of the cuttingedges of the knives was chosen – that with a straight and serrated cutting edge of the chopper. Samples of cutting edgesat 30x magnification, obtained using an instrumental microscope MMI-2, showed that the optimal shape of the knifeis a wedge with a double escapement

NUCLEAR MEAN-FIELD HAMILTONIANS AND FACTORS LIMITING THEIR PREDICTIVE POWER

2010 ◽  
Vol 19 (04) ◽  
pp. 652-664 ◽  
Author(s):  
J. DUDEK ◽  
K. RYBAK ◽  
B. SZPAK ◽  
M.-G. PORQUET ◽  
H. MOLIQUE ◽  
...  
Keyword(s):  
Predictive Power ◽  
Applied Mathematics ◽  
Energy Levels ◽  
Mean Field ◽  
High Quality ◽  
Reliable Determination ◽  
Mathematical Properties ◽  
Particle Spectra ◽  
Determination Of Parameters

In this article we discuss the problem of a reliable determination of parameters of the nuclear mean-field Hamiltonians in view of obtaining high quality comparisons with the experimental single particle spectra: a. In the case of extrapolations to extreme (exotic) isospin nuclei as well as b. In terms of predictions of the energy levels that have not been so far measured also in 'non-exotic' nuclei. We formulate our discussion in terms of the Inverse Problem, a quickly growing sub-field of Applied Mathematics, and introduce a number of mathematical properties which are illustrated in Ref.1 We focus on those mechanisms that may significantly limit the predictive power of the resulting Hamiltonians.

scholarly journals Simulation of the Extruder Screw Parameters

2020 ◽  
Vol 14 (4) ◽  
pp. 71-77
Author(s):  
M. G. Zagoruiko ◽  
V. V. Vasilchikov ◽  
A. K. Mamakhai
Keyword(s):  
Experimental Studies ◽  
Strength Characteristics ◽  
Experiment Planning ◽  
Geometrical Parameters ◽  
Structural Elements ◽  
Structural Element ◽  
Drive Power ◽  
High Quality ◽  
Extruder Screw ◽  
The Press

Extrusion of feed ensures a high quality of the fi nished product.(Research purpose) To increase structural elements durability of the press extruder by optimizing their strength characteristics.(Materials and methods) The authors studied the technological principle of extrusion. The experiment planning method was applied. They examined the process of press extruder operation with a variable pitch screw during the lentils processing. The strength characteristics of the press-extruder elements were checked during design or strength calculations.(Results and discussion) The authors showed the role of the main geometrical parameters of the extruder screw – the slope of the turn and the cutting step – in the preparation of high-quality grain feed. It was found that the turn pitch should be calculated depending on the friction coeffi cient of the starting material against the press-extruder body, the type and properties of the supplied material. The auger fatigue stresses were determined as a result of constant sign shear load and temperature eff ects. The drive power, the extruder productivity were calculated to clarify the screw characteristics, as well as the hydraulic resistance of the matrix output head, the distance of the technological zones. It was confi rmed that the prefabricated screw structure, consisting of sections with diff erent pitch, gave the press extruder versatility.(Conclusions) The authors found that the key was one of the most loaded structural elements of the press-extruder screw. The maximum calculated voltage from a constant load was calculated – 26.98 megapascals. It was determined that the stress in the cross-section of the key under temperature action was 591 megapascals, which exceeded the yield stress for the selected material, equal to 360 megapascals for steel 45. In the course of experimental studies, a value of impact strength was obtained that corresponded to the standard value of the initially selected steel grade (38 kilojoules per cubic meter), but didn’t meet the requirements for this structural element (at least 50 kilojoules per cubic meter).

scholarly journals Analysis of the wood composition in the fiber line of bleached hardwood kraft pulp

2018 ◽  
Author(s):  
Е.О. Окулова ◽  
А.В. Гурьев
Keyword(s):  
Species Composition ◽  
Statistical Significance ◽  
Paper Industry ◽  
Physical And Mechanical Properties ◽  
Raw Material ◽  
Strength Characteristics ◽  
Diagnostic Features ◽  
Perforation Plate ◽  
Wood Composition

В настоящее время лиственные породы древесины широко используются как сырьё для целлюлозно-бумажной промышленности для производства различных волокнистых полуфабрикатов. Основными породами являются осина и берёза. Эти породы отличаются друг от друга по физическим свойствам, химическому составу и морфологии. Известно, что основным диагностическим признаком является отсутствие или наличие лестничной перфорационные пластинки на волокнах сосудов. Прочностные характеристики получаемых волокнистых полуфабрикатов зависят от исходного соотношения в них пород осины и берёзы. Полуфабрикаты с большим содержанием берёзы имеют более высокие показатели механической прочности. Проведен анализ породного состава поступающей щепы на варку и определено соотношение волокон осины и берёзы в волокнистых полуфабрикатах в разных точках технологического процесса производства белёной сульфатной целлюлозы. Породный состав щепы определен путём обработки гидроксидом натрия. Породный состав волокнистых полуфабрикатов определен методом компьютерной визуализации по основным диагностическим признакам. Для подтверждения правильности определения породного состава волокнистого полуфабриката в них установлены прочностные показатели. Анализ полученных данных показал, что колебания породного состава щепы в течение суток могут составлять 12,3–63,7%; размах значений доли волокон осины для проб из выдувного резервуара составляет 23,9–83,6%, для проб из 1-го пресс- фильтра – 18–89,5%. Подтверждена статистическая значимость зависимости физико-механических свойств полуфабрикатов от доли осины и берёзы в волокнистых полуфабрикатах при ее изменении в диапазоне от 10 до 80%. Currently, hardwood is widely used as a raw material for the pulp and paper industry for the production of various fibrous semi-finished products. The main species are aspen and birch. These species differ from each other in physical properties, chemical composition and morphology. It is known that the main diagnostic features are the absence or presence of a staircase perforation plate on the fibers of the vessels. Strength characteristics of the resulting fibrous semifinished products depend on the initial ratio of aspen and birch in them. Semi-finished products with a high birch content have higher mechanical strength. In this paper, the species composition of incoming chips for cooking is analyzed and the ratio of aspen and birch fibers in fibrous semi-finished products at different points in the technological process for the production of bleached sulphate pulp is determined. The native composition of the chips was determined by treatment with sodium hydroxide. The composition of fibrous semi-finished products was determined by computer visualization using the main diagnostic features. To confirm the correctness of the determination of the species composition of the fibrous semifinished product, strength characteristics were determined in them. Analysis of the obtained data showed that fluctuations in the species composition of chips within a day can range from 12.3 to 63.7%; The range of aspen fibers for samples from the blowing tank is 23.9 to 83.6%, for samples from the 1 st press filter – from 18.0 to 89.5%. The statistical significance of the dependence of the physical and mechanical properties of semi-finished products on the share of aspen and birch in fibrous semi-finished products with a change in the range from 10 to 80% has been confirmed.

Determination of parameters of short circuit of power transformer by means of mathematical modeling

2017 ◽  
Vol 26 (102) ◽  
pp. 110-119
Author(s):  
D. S. Yarymbash, ◽  
◽  
S. T. Yarymbash, ◽  
T. E. Divchuk, ◽  
D. A. Litvinov
Keyword(s):  
Mathematical Modeling ◽  
Power Transformer ◽  
Short Circuit ◽  
Determination Of Parameters

Determination of Combined and Second Order Factor Effects for Simultaneous Optimization of Physical and Mechanical Properties of NR/BR Blend System

2014 ◽  
Vol 42 (4) ◽  
pp. 290-304
Author(s):  
Rajarajan Aiyengar ◽  
Jyoti Divecha
Keyword(s):  
Physical And Mechanical Properties ◽  
Second Order ◽  
Simultaneous Optimization ◽  
Order Effects ◽  
Elongation At Break ◽  
Five Factors ◽  
Rubber Compounds ◽  
Polybutadiene Rubber ◽  
Contour Plots

ABSTRACT The blends of natural rubber (NR), polybutadiene rubber (BR), and other forms of rubbers are widely used for enhancing the mechanical and physical properties of rubber compounds. Lots of work has been done in conditioning and mixing of NR/BR blends to improve the properties of its rubber compounds and end products such as tire tread. This article employs response surface methodology designed experiments in five factors; high abrasion furnace carbon black (N 330), aromatic oil, NR/BR ratio, sulfur, and N-oxydiethylene-2-benzothiazole sulfenamide for determination of combined and second order effects of the significant factors leading to simultaneous optimization of the NR/BR blend system. One of the overall optimum of eight properties existed at carbon 44 phr, oil 6.1 phr, NR/BR 78/22 phr with the following values of properties: tensile strength (22 MPa), elongation at break (528%), tear resistance (30 kg/mm), rebound resilience (67%), moderate hardness (68 International rubber hardness degrees) with low heat buildup (17 °C), permanent set (12%), and abrasion loss (57 mm3). More optimum combinations can easily be determined from the NR/BR blend system models contour plots.

Basic set of experiments for determination of mechanical properties of sand

2014 ◽  
Vol 62 (1) ◽  
pp. 129-137
Author(s):  
A. Sawicki ◽  
J. Mierczyński
Keyword(s):  
Mechanical Properties ◽  
Soil Mechanics ◽  
Physical And Mechanical Properties ◽  
Local Strain ◽  
Initial State ◽  
Laboratory Equipment ◽  
Additional Information ◽  
Basic Set ◽  
Initial Anisotropy

Abstract A basic set of experiments for the determination of mechanical properties of sands is described. This includes the determination of basic physical and mechanical properties, as conventionally applied in soil mechanics, as well as some additional experiments, which provide further information on mechanical properties of granular soils. These additional experiments allow for determination of steady state and instability lines, stress-strain relations for isotropic loading and pure shearing, and simple cyclic shearing tests. Unconventional oedometric experiments are also presented. Necessary laboratory equipment is described, which includes a triaxial apparatus equipped with local strain gauges, an oedometer capable of measuring lateral stresses and a simple cyclic shearing apparatus. The above experiments provide additional information on soil’s properties, which is useful in studying the following phenomena: pre-failure deformations of sand including cyclic loading compaction, pore-pressure generation and liquefaction, both static and caused by cyclic loadings, the effect of sand initial anisotropy and various instabilities. An important feature of the experiments described is that they make it possible to determine the initial state of sand, defined as either contractive or dilative. Experimental results for the “Gdynia” model sand are shown.

Disability as a social phenomenon

2020 ◽  
pp. 22-38
Author(s):  
Natalia Guseva ◽  
Vitaliy Berdutin
Keyword(s):  
Social Protection ◽  
Russian Society ◽  
Stage Model ◽  
High Quality ◽  
Rehabilitation Programs ◽  
Current State ◽  
The Social ◽  
Consistent Solution ◽  
First Time

At present, the problem of establishing disability is a point at issue in Russia. Despite the fact that medical criteria for disability are being developed very actively, high-quality methods for assessing social hallmarks are still lacking. Since disability is a phenomenon inherent in any society, each state forms a social and economic policy for people with disabilities in accordance with its level of development, priorities and opportunities. We have proposed a three-stage model, which includes a system for the consistent solution of the main tasks aimed at studying the causes and consequences of the problems encountered today in the social protection of citizens with health problems. The article shows why the existing approaches to the determination of disability and rehabilitation programs do not correspond to the current state of Russian society and why a decrease in the rate of persons recognized as disabled for the first time does not indicate an improvement in the health of the population. The authors proposed a number of measures with a view to correcting the situation according to the results of the study.

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