Research in Agricultural Engineering, 2019 (vol. 65), issue 3
The physical and mechanical properties of potato (Solanum tuberosum L.) tubers as related to the automatic separation from clods and stonesOriginal Paper
Ghasem Abedi, Shamsollah Abdollahpour, Mohammad Reza Bakhtiari
Res. Agr. Eng., 2019, 65(3):77-84 | DOI: 10.17221/24/2018-RAE 
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...
Comparative study of the force action of harvester work tools on potato tubersOriginal Paper
Alexei Siberev, Alexandr Aksenov, Alexei Dorokhov, Andrei Ponomarev
Res. Agr. Eng., 2019, 65(3):85-90 | DOI: 10.17221/96/2018-RAE
The quality of the separation of root crops, onions and potatoes is known to primarily depend on the cultivation conditions. As a rule, these cultures are cultivated in mechanically light soils in order to improve the quality of separation, as well as to reduce the traction resistance of the harvester when extracting the root crops from the soil. When harvesting the root crops, it is very important to maintain the soil in a loose (light) state to improve the quality of the separation. Due to the fact that in digging up the root crops, there is a joint flow of strong soil lumps to the separating working bodies, which are difficult to separate on the...
Innovative and flexible single screw press for the oil extraction of Calophyllum seedsOriginal Paper
Yuli Setyo Indartono, Heriawan Heriawan, Ika Amalia Kartika
Res. Agr. Eng., 2019, 65(3):91-97 | DOI: 10.17221/85/2018-RAE
The oil extraction of Calophyllum seeds using a conventional single screw press leads to an inferior yield and is perceived to be less efficient as well as difficult to operate. An innovative and flexible single screw press was, therefore, designed and investigated in this study to solve these problems. Moreover, the effects of the seeds' moisture content, pressing temperature and seeds' feed rate on the oil yield and quality were identified to determine the optimal oil extraction performance from the Calophyllum seeds. The study found that the seeds' moisture content, pressing temperature and seeds' feed rate generally affected the...
Flare stacks on agricultural biogas plants - safety and operational requirementsOriginal Paper
Petr Trávníček, Luboš Kotek, Vlastimil Nejtek, Tomáš Koutný, Petr Junga, Tomáš Vítěz
Res. Agr. Eng., 2019, 65(3):98-104 | DOI: 10.17221/1/2019-RAE
The flare stack is a piece of equipment, which is used as a safety element at a biogas plant. In the case of a cogeneration unit or gas boiler failure, the biogas is redirected to the flare stack where it is burned. When the flare stack fails, the biogas releases to the atmosphere and an explosive mixture can form. The paper is focused on the description of the causes, which can cause the failure of the equipment. For this purpose, the individual components are described and, subsequently, the possibilities of their failure are discussed. In the next part of the work, the following scenario is considered: failure of the cogeneration unit and flare...