Morphological Characteristics and Physical & Mechanical Properties of seeds of small-seeded crops

Author(s):  
Elchyn Aliiev ◽  
◽  
Christina Lupko ◽  

To create a database and systematize the seeds of samples of small-seeded crops, it is necessary to determine the patterns of influence of morphological parameters on their physical and mechanical properties. The development of the latest technologies and technical devices for cleaning and separation is possible due to the understanding of the characteristic morphological parameters for each of the small-seeded crops. The aim of the research is to determine the physical and mechanical properties of the seed material of small-seeded crops (mustard, flax, ryegrass, rapeseed), necessary to increase the efficiency of their cleaning and separation processes. To achieve this goal, a plan of experimental research was developed, which provided for the determination of physical and mechanical parameters of seeds of small-seeded crops, namely: indicators that characterize the flowability of seeds (angle of natural bias); frictional properties of seeds (static coefficient of friction); porosity (density) and density; size and mass characteristics of seeds (length, width, thickness, effective diameter, weight of 1000 seeds). It is established that the physical and mechanical properties of seeds of small-seeded crops are greatly influenced by its humidity. With increasing humidity, the performance of the test material increases. This is due to the fact that with increasing humidity, the shape of the seed almost turns into a spherical, which, in turn, leads to an increase in the curvature of the surface and reduce the points of contact between the seeds. As a result, the angle of natural inclination increases. The coefficient of friction of seeds of small-seeded crops depends on the roughness of the friction surface and decreases with increasing humidity. This is due to the fact that with increasing humidity decreases the forces of molecular attraction of the seed coat to the surface of the material. Seed density increases with increasing humidity. From this we can conclude that the absorption of moisture by the investigated material increases the total weight of the seed, and as a result - increases its specific weight.

Author(s):  
Igor Nikiforov ◽  
Pavel Maltsev

The role of external friction and chip contraction during microcutting by abrasive grain is showed. The method for determining the relative change in the coefficient of friction during grinding is proposed. The hypothesis about the influence of physical and mechanical properties and microstructure of steel 35 on the volume removes metal through the change in the coefficient of sliding friction of the chip by face of the abrasive grain is experimentally proved.


2022 ◽  
Vol 2159 (1) ◽  
pp. 012014
Author(s):  
P A Garzón-Agudelo ◽  
W Palacios-Alvarado ◽  
B Medina-Delgado

Abstract The 316 L steel is a type of stainless steel widely used in the medical industry, which in recent years has been studied for different uses in society. Being an engineering material, it is imperative to know its performance based on its physical and mechanical properties that allow identifying the response of this steel in addition to thin films as coatings. Bismuth and titanium have been recently used to improve the properties of 316 L steel, so they were used in this study. The sol-gel technique was used as the film forming method. The response of physical and mechanical properties was evaluated from the analysis of microhardness and coefficient of friction reported for the different types of steel-coating systems. Higher microhardness values were found for films with higher proportion of titanium. The coefficient of friction values is influenced by the system used, with higher values obtained for samples with a single coating layer.


Author(s):  
Н. П. Супрун ◽  
М. Л. Рябчиков ◽  
І. О. Іванов

Create a model for determining the coefficient of friction of textile materials to identify the main factors influencing the process of friction, taking into account the structural and mechanical properties of materials. Modeling of friction process in textile materials as a combination of adhesive and elastic phenomena. Roughness of solid bodies and the main parameters of roughness, such as the height of micro-irregularities, their pitch, sharpening, etc. described in many standards and scientific papers. However, the modeling of the friction process in such systems is very complicated due to the irregularity of distribution of microroughness. The analysis of literature data showed that the surface roughness of textile materials is an important and effective factor in predicting the tactile properties of products for various purposes. Estimation of surface roughness is usually carried out using subjective and objective methods, and the latter can be contact and non-contact. The paper develops a model for determining the coefficient of friction of textile materials to identify the main factors influencing the friction process, taking into account the structural and mechanical properties of materials. Friction force is presented as a combination of two main factors. The first is the elastic resistance to deformation, the second is the adhesive resistance to compression of the structural elements of the material. The main parameters influencing the coefficient of friction of textile fabrics - modulus of elasticity of structural elements, their geometrical parameters - surface density of textile material, linear density of structural elements are established. The obtained results allow to qualitatively predict the friction forces of a textile material with known parameters of its structural elements, as well as to normalize these parameters to create materials with specified friction indices. The obtained results make it possible to select the threads that form the textile material, according to the values of the modulus of elasticity, thickness, location density to ensure the minimum friction force.


Author(s):  
S. O. Maranda ◽  
V. V. Adamchuk

Annotation Purpose. Determination of the influence of parameters and modes of operation of the dosing and scattering device on the speed characteristics of the movement of grain moth eggs infected with trichogramma. Methods. Theoretical studies of the process of particle motion of the test material by the dosing and scattering device were performed using the basic laws of classical theoretical mechanics. Results. On the basis of the analysis of means for settlement of a trichogram the design of the dosing and scattering device of the unmanned aerial vehicle (UAV) for settlement of a trichogram is defined. According to the results of theoretical studies, it was concluded that in order to achieve high velocity characteristics of the trichogram movement, the length of the diffuser-deflector deflector, the radius of curvature of the deflector and the angle of the deflector sector must have parameters at which the trichogram will be minimally reduced. The material from which the dosing and dispensing device is made must have the lowest possible coefficient of friction. Conclusions 1. According to the results of theoretical research it is established that with increasing: the curvature of the deflector arc from 0.03 m to 0.09 m and the angle of the deflector sector 0° to 90°, the speed of the trichogram varies from 5 m/s to 3.5 m/s. 2. To increase the width of the capture when performing the technological operation of settling the trichogram, the angle of the deflector sector should be in the range of 45–90°. 3. When changing the coefficient of friction from 0.2 to 0.9, the velocity of the particle decreases from 4.61 m/s to 3.5 m/s. With an increase in the coefficient of friction in 2 times the speed decreases by 8%. Keywords: theory of material particle motion, dosing and scattering device, unmanned aerial vehicle, biological plant protection, trichogram settlement, settlement norm, capture width.


2019 ◽  
Vol 14 ◽  
pp. 155892501989056
Author(s):  
Eui Kyung Roh

As a lot of time is spent in the car, the comfort of not only the car seat but also the car seat cover itself has become of increasing importance. With increasing use of ventilated seats, the control of the physical and mechanical properties of leather in response to punching has become of prime importance in the design of car seats. This study evaluated the changes in the physical and mechanical properties of leather due to punching and proposes optimum punching intervals for car seats. Sixteen types of leather, punched at three spatial intervals (2, 3, and 5 mm), were evaluated in terms of their apparent density, softness, coefficient of friction, warm-cool feeling, and mechanical properties. Leather punching affected its physical and mechanical properties. However, there were differences in punching intervals that significantly affected each property, including the mechanical properties. Depending on the performance required when developing a product, a suitable punching interval must be selected. Therefore, punching at 5 mm intervals is preferred for obtaining physical and mechanical properties similar to those of untreated leathers, and punching at 3 mm intervals is recommended for achieving more softness. On the contrary, punching at 2 mm intervals increases air permeability but decreases dimensional stability.


2014 ◽  
Vol 931-932 ◽  
pp. 1574-1581
Author(s):  
Nirattisak Khongthon ◽  
Somposh Sudajan

The physical and mechanical properties of sugarcane leaves were necessary for the design consideration of the relating storage, handling and processing equipment. The sugarcane trash at moisture contents of 23.40 and 73.91 % w.b. were used for this study. The mean length and unit weight of sugarcane trashes were 168.63 cm and 65.87 grams respectively. The average number of leaf of each sample was 4. The mean diameter of the thrash top, width and thickness increased with the increase of moisture from 23.40 and 73.91 % w.b.. The average leaf angles (β) relative to the horizontal plane of the first left leaf, second left leaf, first right leaf and second right leaf were 65.10, 73.36, 71.07 and 78.26 degrees for 73.91 % w.b., and 66.33, 73.50, 67.50 and 75.83 degrees for 23.40 % w.b. respectively. When the moisture content increased from 23.40 to 73.91% w.b., the static coefficient of friction increased from 0.30 to 0.43, 0.38 to 0.41, 0.30 to 0.37 and 0.54 to 0.66 for plywood, mild steel, galvanized iron and rubber plate respectively. The least static coefficient of friction occurred on the galvanized iron plate. The results from experimenting on mechanical properties showed that the maximum shearing force increased with the increase in moisture content from 23.40 to 73.91% w.b. respectively. The maximum shearing force was 360.15 and 457.32 N for moisture contents of 23.40 and 73.91% w.b.. The maximum tensile force decreased toward upper region of the leaf for both 23.40 and 73.91% w.b.. The results of this study would be useful for the design and optimization of the equipment associated with harvesting, threshing, chopping and processing.


Author(s):  
Ghasem Abedi ◽  
Shamsollah Abdollahpour ◽  
Mohammad Reza Bakhtiari

In the current research, some of the mechanical and physical properties of two industrial varieties of potato tubers that have a prominent role in the mechanised separation process from clods and stones were investigated. These properties include the physical dimension, mass, volume, sphericity, surface area, density, projected areas and Young’s modulus. In addition, the static coefficient of friction and rolling resistance for tubers on five surface materials were determined. The tuber’s size positively affected the physical and mechanical properties of the tubers. The frictional properties of the tubers were affected by the tuber size, the surface type, and the interaction between them. The results showed that most of the apparent properties for the Sante variety were greater than those of the Marfona variety. The static coefficient of friction for the tubers on a wood surface was the maximum and was the minimum value on a galvanized sheet, but for the tuber’s rolling resistance, the results were inversed. The results proposed that the automatic separation of the potato tubers from the impurities using the properties of the crop is possible.


1997 ◽  
Vol 67 (5) ◽  
pp. 342-347 ◽  
Author(s):  
Lieva Van Langenhove

Part I established a theoretical model that was able to predict the stress-strain and torque-strain curves of a yarn. This second part evaluates the model. The influence of fiber and yarn parameters on the predicted values is also discussed. The most critical fiber property is the coefficient of friction.


2019 ◽  
Vol 65 (No. 2) ◽  
pp. 48-55
Author(s):  
Abbas Akbarnia ◽  
Mahdi Rashvand

The determination of the physical and mechanical properties of agricultural products has always been considered as the basis for the design and fabrication of transmission, grading, and processing equipment for agricultural products. Due to the increasing production of olives and the foreign exchange earnings from its trade, the mechanisation of harvesting and processing operations is inevitable. Therefore, the aim of this study was to evaluate the physical, dynamic and aerodynamic properties of olive species in order to design and fabricate an olive oiling machine. In this research, four species of olives, namely the Manzanilla, Kalamata, Fishemi, and Oily, were used. The physical properties of the samples were completely different. The mean dimensions of the Manzanilla species are the largest and the Oily is smallest and were the inverse in relation to the sphericity index. To determine the mechanical properties of the samples, the test material was used at a speed of 8 mm·min–1. The results showed that the maximum and minimum power and energy of rupture were allocated to the Manzanilla and Oily species, respectively. The Oily samples have the most mechanical sensitivity when compared to the other samples. The aerodynamic properties of the olive species were measured using a wind tunnel. The highest velocity and drag coefficient were assigned to the Oily sample and the lowest values were assigned to the Kalamata sample.


2007 ◽  
Vol 539-543 ◽  
pp. 2778-2781 ◽  
Author(s):  
Zhen Kai Xie ◽  
Yasuo Yamada ◽  
Takumi Banno

Highly porous materials with a cellular structure are known to have many interesting combinations of physical and mechanical properties, such as very low specific weight combined with high thermal conductivity. However, when the pore size of the foam metal grows, the strength maintenance is scarce because the array of the pore is not uniform. In the present work, micro porous aluminum with porosities between 5% and 50% and pore sizes of 20~50 μm was produced by applying the powder metallurgical technique, i.e. by sintering the aluminum metal powders and PMMA powder mixture at 913 K. The effect of sintering temperature on the compressive properties of porous aluminum was investigated. The effects of particle size and fraction of space holding particle and metal powder on the porosity pore size and mechanical properties of porous sintered specimens were mainly investigated. The pore size of porous aluminum can be controlled by changing the PMMA powder diameter. The results show the fabrication of the micro porous aluminum with middle porosity and high strength is possible.


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