scholarly journals ՀԱՑԱՀԱՏԻԿԻ ՄՇԱԿՈՒԹՅԱՆ ՏԵԽՆՈԼՈԳԻԱՅԻ ԿԱՏԱՐԵԼԱԳՈՐԾՈՒՄԸ ՔԻՄԻԱԿԱՆ ՊԱՅՔԱՐԻ ՆՎԱԶԵՑՄԱՆ ՀՆԱՐԱՎՈՐՈՒԹՅՈՒՆՆԵՐԻ ԿԻՐԱՌՄԱՄԲ. ՑԱՆՔԻ ՏԵԽՆՈԼՈԳԻԱԿԱՆ ՆՈՐԱՄՈՒԾՈՒԹՅԱՆ ՏԵՍԱԿԱՆ ՀԻՄՆԱՎՈՐՈՒՄԸ

2021 ◽  
pp. 31-35
Author(s):  
D. P. Petrosyan ◽  
S. V. Rafayelyan

The second article of the series considers the theoretical justification of technological innovations for cereal crop seeding. The effect of the seeding ploughshare on the seed grain and soil has been investigated. A new seeding technology in line with agro-technical requirements, structural parameters of the ploughshare, physicotechnological properties of soil and seed has been developed. The recommended technological and structural solutions can serve as a background for conducting respective scientific experiments in future.

Author(s):  
Yongzhe Ma ◽  
Peisheng Zhang

In-pile irradiation capsules are used for fuel and material irradiation at research reactor. Design of irradiation capsule should be based on thermal analysis to determine the key structural parameters. A set of out-of-pile heat transfer test device is innovated for the design validation. Heat transfer performance of in-pile irradiation capsule can be simulated, which includes heat conduction, convection and radiation. Electric heating rod is used as the heat source for the device, which simulates linear power or heat flux of in-pile irradiation capsule. Temperature different of internal components is simulated by adjusting helium gap. Thermocouples are fixed to measure wall temperature and internal temperature of the components in the device. Some out-of-pile heat transfer tests have been carried out for irradiation capsule development for China Advanced Research Reactor (CARR) and China Experimental Fast Reactor (CEFR) at China Institute of Atomic Energy (CIAE). The test verifies surface and internal temperature of the capsules and conclusions of thermal analysis. A finished in-pile test verifies the capsule design at rated power, which also proves that results of the out-of-pile heat transfer test are conservative. The article describes the function, structure, test process and other aspects of the technical requirements of the heat transfer test device.


2012 ◽  
Vol 490-495 ◽  
pp. 509-513
Author(s):  
Ji Zhu Liu ◽  
Ming Chong Sun ◽  
Tao Chen ◽  
Ming Qiang Pan

Compared with steam catapult device, electromagnetic catapult device has high catapult energy, low system weight, high efficiency etc., so electromagnetic catapult makes an important developing direction for the aircraft carrier catapult. According to the technical requirements of electromagnetic catapult, the paper analyses the factors that affect the efficiency of electromagnetic catapult, proposes the method of using slotting PMLSM in low-speed segment and non-slotting PMLSM in high-speed segment to drive, which improves the systematic efficiency of the catapult process. The paper designs a structure of PMLSM assembled by stator modules. Also researches on PMLSM using the designing method of finite element, analyses the structural parameters the influences have on the thrust force of slotting and non-slotting motor, presents the optimal motor structural parameters, and at last proves the correctness of the theoretical analysis through experiment.


2019 ◽  
Vol 2019 (2) ◽  
pp. 270-274
Author(s):  
P Grigoriev ◽  
◽  
Sh Ibodulloev ◽  
B Poyonov

An approach for defining critical temperatures of buckling for a pivotally resting plane cylindrical shell has been considered. Operation in various climatic zones leads to buckling of roof elements of passenger cars. In connection with that, it is necessary to have a theoretical justification of structural solutions taking into account critical temperatures of buckling of shell elements. The roof element of the passenger car should be classified as plane cylindrical shells. An expression for defining critical temperatures by the Bubnov-Galerkin method has been obtained, as well as the equations of plane cylindrical shells proposed by V.Z. Vlasov. The results calculated with the derived expression have been verified by comparison with those obtained by the finite element method (FEM). This comparison has demonstrated satisfactory agreement of these results.


2020 ◽  
Vol 24 (1) ◽  
pp. 23-34
Author(s):  
V. V. Kuts ◽  
V. V. Ponomaryov

Purpose of research. The study is devoted to improving the resistance characteristics of an interlocking side milling cutter with a constructive radial feed when processing extended RK profile shafts while maintaining the required quality of surface treatment.Methods. Forming of RK profiles by milling with a disk cutter with a constructive radial feed allows you to obtain the required surface quality with high processing productivity. Due to the fact that the processing conditions for each cutting insert are different, it is necessary to study the resistance of interchangeable polyhedral inserts (IPI) and to search for structural solutions to reduce the range of change in resistance, while maintaining the quality of surface treatment of the PK profile. The influence of the use of an uneven pitch of location both on the quality of processing and on the resistance of each individual insert is studied.Results. The paper presents a method for calculating the resistance of an IPI of a interlocking side milling cutter during processing of an extended RK profile of a shaft, taking into account the individual conditions of their operation, namely: cutting speed, feed to the tooth, milling width and the diametrical position of the IPIConclusion. The analysis of the influence of the structural parameters of the cutter on changing the range of values of the resistance of IPI is made, and recommendations for its reduction are proposed. The main design parameters that affect the change in the resistance range are also identified.


Author(s):  
L.F. Babitsky ◽  
◽  
V.A. Kuklin ◽  

The aim of the research is to substantiate the parameters of the stable stroke along the depth of the vibrating tillage working bodies on spring struts. The article proposes an elastic-viscous rheological model of the soil and provides a theoretical justification for the parameters of the stable course along the depth of the vibrating working bodies on spring struts. The resulting expression includes agrotechnological and structural parameters, as well as physical and mechanical properties of the soil.


2009 ◽  
Vol 23 (2) ◽  
pp. 117-127 ◽  
Author(s):  
Astrid Wichmann ◽  
Detlev Leutner

Seventy-nine students from three science classes conducted simulation-based scientific experiments. They received one of three kinds of instructional support in order to encourage scientific reasoning during inquiry learning: (1) basic inquiry support, (2) advanced inquiry support including explanation prompts, or (3) advanced inquiry support including explanation prompts and regulation prompts. Knowledge test as well as application test results show that students with regulation prompts significantly outperformed students with explanation prompts (knowledge: d = 0.65; application: d = 0.80) and students with basic inquiry support only (knowledge: d = 0.57; application: d = 0.83). The results are in line with a theoretical focus on inquiry learning according to which students need specific support with respect to the regulation of scientific reasoning when developing explanations during experimentation activities.


1865 ◽  
Vol 13 (3) ◽  
pp. 32-35
Author(s):  
James Glaisher

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