Tag Archives: Deformation

393–403 D. Derevjanko, I. Holovach, V. Bulgakov, V. Kuvachev and, J. Olt
Theoretical and experimental research into impact of threshing tools in combine grain harvesters on quality of cereal crop seeds
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Theoretical and experimental research into impact of threshing tools in combine grain harvesters on quality of cereal crop seeds

D. Derevjanko¹, I. Holovach², V. Bulgakov², V. Kuvachev³ and, J. Olt⁴*

¹Zhytomyr National Agroecological University, 7, Staryi Blvd, UA 10008 Zhytomyr, Ukraine
²National University of Life and Environmental Sciences of Ukraine, 15, Heroyiv Oborony street, UA 03041 Kyiv, Ukraine
³Dmytro Motornyi Tavria State Agrotechnological University, 18B, Khmelnytsky Ave, UA 72310 Melitopol, Zaporozhye Region, Ukraine
⁴Estonian University of Life Sciences, Institute of Technology, Kreutzwaldi 56, EE 51006 Tartu, , Estonia
*Correspondence: jyri.olt@emu.ee

Abstract:

The theoretical and experimental research into the micro-damaging of cereal crop seeds in the process of their harvesting by combine grain harvesters in relation to the strains, forces and stresses imparted to them by the threshing tools has been carried out. The propagation of deformations and cracks in the seeds as well as the nature of their strength and the damage that is sustained, when the critical load is applied, have been investigated. It has been established that the onset of cracks, the direction of their propagation and their quantity in the bodies of grain seeds depends in the majority of cases on the direction of action of the external forces and the specifics of the seeds’ internal biological properties. It has been established that the strength of the grain seed is, apart from the arisen cracks, also under the significant effect of the microtraumas in the germ, endosperm as well as the seed coat and shell. Theoretical calculations have been carried out on the PC and the effect that the drum and rotor threshing apparatus have on the deformation and damage sustained by cereal crop seeds has been substantiated. The said calculations and the obtained graphic relations support the results of the experimental investigations and prove that the macro- and especially micro-damage sustained by the seeds of winter wheat and rye is different, when they are threshed with the use of different types of threshing apparatus, which has a considerable impact on the final quality of the harvested cereal crop seeds. The results obtained in the experimental investigations, field and laboratory tests on the topic of the effect of mechanical loading on the sustained damage and quality of seeds indicate that the damage rate accounted for the work processes of the reaping and postharvest treatment of the cereal crop heaps of different winter wheat varieties with the use of rotor threshing apparatus is 3.1% as compared to the drum threshing apparatus – 6.4%, that is, 2 times lower. The total amount of the seeds with microtraumas collected in the hopper after threshing amounts to 23.0% and 54.0%, respectively, which is a significant difference. Similar results have been obtained in the experimental investigations on the effect of the equipment on the sustained damage and quality of seeds in the cleaning, chemical treatment and sowing of cereal crops.

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38–52 V. Bulgakov, I. Holovach, Z. Ruzhylo, I. Fedosiy, Ye. Ihnatiev and J. Olt
Theory of oscillations performed by tools in spiral potato separator
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Theory of oscillations performed by tools in spiral potato separator

V. Bulgakov¹, I. Holovach¹, Z. Ruzhylo¹, I. Fedosiy¹, Ye. Ihnatiev² and J. Olt³*

¹National University of Life and Environmental Sciences of Ukraine, 15 Heroyiv Oborony Str., UA 03041 Kyiv, Ukraine
²Tavria State Agrotechnological University, 18B Khmelnytsky Ave, UA 72310 Melitopol, Zaporozhye Region, Ukraine
³Estonian University of Life Sciences, Institute of Technology, 56 Kreutzwaldi Str., EE 51006 Tartu, Estonia
*Correspondence: jyri.olt@emu.ee

Abstract:

The aim of this study is to provide for the intensification of the process of removing impurities from the potato heap by oscillating devices, which takes place, when potato tubers are cleaned in the spiral separator during their lifting. The authors have devised a new design of the spiral separator, which can be used in the process of lifting potatoes from the soil. It comprises cantilever cleaning spiral springs, which in their simultaneously rotary and oscillatory motion clean and transport the potato tubers with good quality. However, the removal of impurities from the cleaning area and the cleaning of the side surfaces of potato tuber bodies from the stuck soil can be significantly more effective, if the spiral springs perform their oscillatory motions in the longitudinal and vertical plane during their operation more intensively. In order to achieve that, the authors have worked out a new theory of the oscillatory motion of the cleaning spiral working under the action of the potato heap. That promotes the intensification of the process of cleaning potato bodies from the stuck soil. The authors have generated a new partial differential equation, which describes the oscillations of the cantilever cleaning spiral. The PC-assisted numerical solving of the said differential equation and further numerical modelling have made it possible to obtain the analytic expressions of the relations between the change in the helix pitch distance of the cleaning spiral and its deformation, in particular, the simultaneous longitudinal extension and transverse bending. That result, in its turn, provided for finding the maximum limit amount of the above-mentioned deformation under the condition that the potato tubers may not fall through the spaces between the spiral turns, taking into account the design and kinematic parameters of the cleaning spiral itself, the material it is made of and the process-dependent mode of operation of the separator. As a result of the PC-assisted numerical modelling, it has been found that the total deflection of the spiral on its length varies within the range of 0 to 0.05 m under the following parameters: angular velocity of rotation of the spiral ω = 30 rad s-1, density of the material of the spiral ρ = 7,700 kg m-3, elastic modulus Е = 2∙1011 Pa, cleaning spiral bar stock radius r = 8.5 mm and a uniform load intensity of 1000 N m-1. Such variation ensures the good quality of cleaning and transportation of potato tubers. According to the results of the PC-assisted numerical calculations, the helix pitch distance of a cleaning spiral with the above parameters and the original helix pitch distance S = 48 mm, due to the spiral’s deformation under the proposed transverse oscillations, can change up to 54 mm, which makes impossible for potato tubers to fall out of the cleaning unit. Experimental studies fully support the results from the theoretical calculations to determine the displacement of the ends of the cleaning unit’s spiral springs.

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1829-1843 L. Nilova, R. Ikramov and S. Malyutenkova
The possibility of using microwaves to obtain extracts from berry press residues and jelly products with bioactive characteristics
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The possibility of using microwaves to obtain extracts from berry press residues and jelly products with bioactive characteristics

L. Nilova*, R. Ikramov and S. Malyutenkova

Peter the Great St. Petersburg Polytechnic University, Institute of Industrial Management, Economics and Trade, Graduate School of Service and Trade, Novorossiyskaya street 50, RU194021 Saint-Petersburg, Russia
*Correspondence: nilova_l_p@mai.ru

Abstract:

The paper explores the possibility of development a microwave technology for obtaining water extracts from berry press residues (wild bilberries and cranberries as the objects) and jelly products based on them, which will allow using the waste of freshly squeezed juices in business, such as restaurants and catering services. The antioxidant activity (DPPH and FRAP methods), content of phenolic compounds, flavonoids, anthocyanins, ascorbic acid were determined in berries and in berry press residues. The antioxidant activity of bilberry press residues was due to anthocyanins, and the activity of cranberry press residues was due to flavonoids. Using the microwave oven (magnetron power 800 W, frequency 2,450 MHz), water extracts were obtained in the ratio: for cranberries 1.5:10, for bilberries 1:10. The antioxidant activity of extracts depended on the type of berries and was greater in extracts from bilberry press residues. Extracts of bilberries and cranberries and their compositions (sugar-free and sugar-added) with gelatin as a gelling agent were used to produce the jelly products. Combining bilberry and cranberry extracts (70:30) with gelatin makes it possible to obtain jelly products without sugar. Heating of the ready recipe mixture after preliminary swelling of gelatin and without swelling of gelatin was carried out in the microwave oven. The antioxidant activity of jelly products was higher when using bilberry extracts than cranberries. An increase in the antioxidant activity of the extracts led to a slowdown in structure formation, but increased the plasticity of the products.

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13–21 O.L. Akangbe, J. Blahovec, R. Adamovský, M. Linda and M. Hromasova
Effects of selected process parameters on the compaction of carob powder
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Effects of selected process parameters on the compaction of carob powder

O.L. Akangbe¹*, J. Blahovec², R. Adamovský¹, M. Linda³ and M. Hromasova³

¹Czech University of Life Sciences, Faculty of Engineering, Department of Mechanical Engineering, Kamycka 129, CZ16521 Praha 6 – Suchdol, Prague, Czech Republic
²Czech University of Life Sciences, Faculty of Engineering, Department of Physics, Kamycka 129, CZ16521 Praha 6 – Suchdol, Prague, Czech Republic
³Czech University of Life Sciences, Faculty of Engineering, Department of Electrical Engineering, Kamycka 129, CZ16521 Praha 6 – Suchdol, Prague, Czech Republic
*Correspondence: akangbe@tf.czu.cz

Abstract:

The effects of important process parameters on mechanical response during the densification of an industrial food powder were investigated and important phenomena described using the power rule. The factors studied had highly significant effects on mechanical response. The effects of the models in predicting the behaviour of the system were also highly significant. The findings are of relevance to processing and handling of food powders.

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1078–1087 M. Müller and R. Chotěborský
Impact strength behaviour of structural adhesives
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Impact strength behaviour of structural adhesives

M. Müller* and R. Chotěborský

Department of Material Science and Manufacturing Technology, Faculty of
Engineering, Czech University of Life Sciences, Kamýcká 129, CZ 165 21 Prague,
Czech Republic
*Correspondence: muller@tf.czu.cz

Abstract:

A cohesive force at an adhesive bond is one of the limit for a strength of an adhesive bonding. This study is focused on an impact force of an adhesive. Samples without a notch were cast in the casting mould at a laboratory temperature with a normal pressure. The instrumentation microcharpy test equipment was used for the evaluation of the impact force. The samples were tempered at a laboratory temperature, 40 °C and 60 °C. Results showed that the temperature of the specimens influenced the impact strength, the toughness and the maximum deformation of the adhesives. Higher temperature decreased the impact force but it increased the toughness. The hardness Shore D of commercial filled two-component epoxies is comparable. A nonhomogeneity of adhesives distinguished for a porosity was found by the investigation of a fracture surface.

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