scholarly journals MODEL OF THE QUALITY-POWER INDICATOR OF A ROTARY DRUM MIXER

2020 ◽  
pp. 107-113
Author(s):  
А.В. Чупшев ◽  
В.В. Коновалов ◽  
К.П. Фудин

На основании экспериментальных исследований в статье изложены вопросы повышения качественных показателей работы барабанного смесителя кормов, представлено описание его конструкции и принцип работы. Исследования проводились в соответствии с действующей методикой и материалами, представленными в статье. По результатам аппроксимации исходно рассчитанных значений качественно-мощностного показателя получена статистическая модель данного качественно-мощностного показателя (0,01 %∙кВт). Осуществлен анализ величины ошибок расчетных данных на предмет соответствия исходным данным. После обработки полученных экспериментальных данных приведено описание графических зависимостей по влиянию конструктивных параметров рабочего органа барабанного смесителя на качественно-мощностной показатель. Увеличение высоты установки лопастей нежелательно свыше 0,16 м, а увеличение количества лопастей свыше восемь штук приводит к резкому ухудшению количественно-мощностного показателя. Даны соответствующие выводы по применению исследуемых конструктивных и режимных параметров при работе барабанного смесителя. Based on experimental studies, the article presents the issues of improving the quality indicators of the drum feed mixer, describes its design and operating principle. The research was conducted in accordance with the current methodology and materials presented in the article. Based on the results of approximation of the initially calculated values of the quality-power indicator, a statistical model of this quality-power indicator (0.01% kW) is obtained. The value of errors in the calculated data is analyzed for correspondence with the initial data. After processing the obtained experimental data, the description of dependence diagrams on the influence of the design parameters of the working body of the drum mixer on the quality and power indicator is shown. An increase in the height of the installation of blades is undesirable over 0.16 m, and an increase in the number of blades over eight leads to a rapid deterioration in the quantity-power indicator. The relevant conclusions on the application of the studied design and operating parameters in the working of the drum mixer are presented.

2019 ◽  
Vol 968 ◽  
pp. 234-239
Author(s):  
Talyat Azizov ◽  
Oleksii Melnik ◽  
Oleksandr Myza

The results of experimental studies of combined beams consisting of a stone part, reinforced with side reinforced concrete plates are given. Experimentally shown the viability of the proposed structures. The conditions for ensuring the combined action of a stone beam and a reinforced concrete plate are given. Cases are shown when one-sided plates can be used and when double-sided reinforced concrete plates can be used. A comparison of experimental data with the data calculated by the authors developed methods is given. A good agreement between theoretical and calculated data is shown.


2020 ◽  
Vol 143 (3) ◽  
Author(s):  
Girijesh Mathur ◽  
Nachiketa Tiwari ◽  
Neha Chaturvedi

Abstract A ballistic compression type soft recovery system can stop a free-flying supersonic projectile in a controlled manner. The moment such a projectile enters the System, a normal shock gets created and starts hurtling down, to kick off a train of events involving shock reflections, diaphragm rupture, shock merger, creation of new shocks and contact discontinuities, and expansion wave-shock interactions. A good understanding of these phenomena and sensitivity of the System's performance to changes in design parameters is needed to design an efficient soft recovery system. Unfortunately, not much information is available about this. The present work fills this gap. We have developed a numerical model for the system and conducted sensitivity analyses using four design parameters; pressure, molecular weight, the ratio of specific heats, and temperature of gas used in the system. We show that while there is a strong, positive correlation between the first two parameters and projectile deceleration, the other two parameters are less critical. We conducted experiments to corroborate our conclusions and improve our numerical model. Post such improvements, we found the difference between simulation and experimental data to be acceptable. Experiments also confirmed the findings of our sensitivity studies. Finally, we conducted a two-dimensional finite volume analysis to understand the reasons underlying the residual difference between our numerical and experimental data. We show that such differences are due to pressure-rise at a point once a shock passes by it, and such a rise in pressure is attributable to boundary layer effects.


2021 ◽  
Vol 274 ◽  
pp. 03001
Author(s):  
Boborakhim Urishev ◽  
Sobir Eshev ◽  
Fakhriddin Nosirov ◽  
Ulugbek Kuvatov

It has been determined that the reduction of siltation of the front chamber is necessary because the deposited sediments seriously violate the planned hydraulic structure of the flow when water is sucked up by pumps, as a result of which their efficiency decreases. The method of calculating the pipeline system of a new device designed to significantly reduce the siltation of the front chamber of irrigation pumping stations by artificially creating turbulence in the water flow in the bottom layer of the structure is presented. This calculation methodology is based on the use of the theory of flooded water jets, which makes it possible to determine the main characteristics of the jet. The latter allows calculating the design parameters of the pipeline system. The results of experimental studies are presented to compare the calculated data with the results of experiments, as well as to determine the effectiveness of the proposed device for a significant reduction in siltation of the front chamber of irrigation pumping stations.


2021 ◽  
Vol 7 (2) ◽  
pp. 79-84
Author(s):  
Aleksandra V. Voronina ◽  
Sergey V. Pavlov

The paper considers the problem of selecting a turbulence model to simulate natural convection near the surface of a VVER-1000 fuel assembly unloaded from the reactor by computational fluid dynamics (CFD simulation) methods. The turbulence model is selected by comparing the calculated data obtained using the Ansys Fluent software package with the results of experimental studies on the natural convection near the surface of a heated vertical plate immersed in water, which simulates the side face of the VVER-1000 fuel assembly in a first approximation. Two-parameter semi-empirical models of turbulence, k-ε and k-ω, are considered as those most commonly used in engineering design. The calculated and experimental data were compared based on the excessive temperature of the plate surface and the water temperature profiles in the turbulent boundary layer for convection modes with a Rayleigh number of 8∙1013 to 3.28∙1014. It has been shown that the best agreement with experimental data, with an average deviation not exceeding ~ 8%, is provided by the RNG k-ε model which is recommended to be used to simulate natural convection near the surface of VVER-1000 FAs in the NPP spent fuel storage pool.


Author(s):  
K. A. Zaplohova ◽  
G. S. Isaev ◽  
A. E. Kurepin ◽  
E. V. Sidorova

When assessing the effectiveness of ammunition designed to destroy various aerodynamic and ballistic targets, as the initial data on the vulnerability of the destruction objective, we use indicators obtained during experimental studies of the processes of fragments and fragment flow collision with various fragments of the target design. The results depend not only on the speed and mass of individual fragments, but also on their shape and location in the flow. The paper gives the results of the testing of an explosive thrower which provides the creation of a high-speed, i.e. ~5 km/s, flow of fragments of a given shape. Findings of research show satisfactory agreement between the results of calculations carried out in two- and three-dimensional statements with experimental data on high-speed throwing of a group of compact, parallelepiped, steel preformed fragments weighing 20 g each


Author(s):  
Jane Klavan ◽  
Ann Veismann

Recent work in usage-based linguistics stresses the importance of combining corpus-based analyses with experimental studies. A number of studies have compared the performance of a corpus-based statistical model against the behaviour of native speakers in a linguistic experiment. The present paper takes this line of analysis further by combining corpus-based work with two sources of experimental data. A mixedeffects logistic regression model is fitted to the corpus data of the Estonian adessive case and the adposition peal ‘on’ in present-day written Estonian. In order to evaluate the goodness of the corpus-based model, its performance is compared to the behaviour of native speakers in a forced choice task and a rating task.Kokkuvõte. Jane Klavan ja Ann Veismann: Kas keelekasutajate valikud ja hinnangud peegeldavad korpuspõhiseid tõenäosushinnanguid? Eesti keele adessiivi ja kaassõna peal kasutus tänapäeva kirjakeeles. Tänapäevases kasutuspõhises keeleteaduses rõhutatakse vajadust kombineerida korpusandmetele toetuvat analüüsi katseliste uuringutega. Mitmed uurimused on võrrelnud korpusel põhineva statistilise mudeli headust emakeelsete kõnelejate käitumisega keelelistes katsetes. Käesolev artikkel jätkab seda uurimisliini, pannes võrdlusesse korpusandmetega kaks keelelist katset. Artiklis hinnatakse korpuspõhise segamudeli headust, võrreldes seda eesti keelt emakeelena kõnelejate käitumisega sunnitud valiku katses ja hinnangukatses. Uuritavaks nähtuseks on eesti keele adessiivi ja kaassõna peal rööpne kasutus kohasuhete väljendamisel tänapäeva kirjakeeles.Võtmesõnad: konstruktsioonilised alternatsioonid; korpuslingvistika; sunnitud valiku katse; hinnangukatse; statistiline mudeldamine; eesti keel


2018 ◽  
Vol 84 (10) ◽  
pp. 23-28
Author(s):  
D. A. Golentsov ◽  
A. G. Gulin ◽  
Vladimir A. Likhter ◽  
K. E. Ulybyshev

Destruction of bodies is accompanied by formation of both large and microscopic fragments. Numerous experiments on the rupture of different samples show that those fragments carry a positive electric charge. his phenomenon is of interest from the viewpoint of its potential application to contactless diagnostics of the early stage of destruction of the elements in various technical devices. However, the lack of understanding the nature of this phenomenon restricts the possibility of its practical applications. Experimental studies were carried out using an apparatus that allowed direct measurements of the total charge of the microparticles formed upon sample rupture and determination of their size and quantity. The results of rupture tests of duralumin and electrical steel showed that the size of microparticles is several tens of microns, the particle charge per particle is on the order of 10–14 C, and their amount can be estimated as the ratio of the cross-sectional area of the sample at the point of discontinuity to the square of the microparticle size. A model of charge formation on the microparticles is developed proceeding from the experimental data and current concept of the electron gas in metals. The model makes it possible to determine the charge of the microparticle using data on the particle size and mechanical and electrical properties of the material. Model estimates of the total charge of particles show order-of-magnitude agreement with the experimental data.


2020 ◽  
Vol 92 (6) ◽  
pp. 13-25
Author(s):  
Vl.I. KOLCHUNOV ◽  
◽  
A.I. DEMYANOV ◽  
M.M. MIHAILOV ◽  
◽  
...  

The article offers a method and program for experimental studies of reinforced concrete structures with cross-shaped spatial crack under torsion with bending, the main purpose of which is to check the design assumptions and experimental determination of the design parameters of the proposed calculation method. The conducted experimental studies provide an opportunity to test the proposed calculation apparatus and clarify the regularities for determining deflections, angles of rotation of extreme sections, and stresses in the compressed zone of concrete. For analysis, the article presents a typical experimental scheme for the formation and development of cracks in the form of a sweep, as well as characteristic graphs of the dependence of the angles of rotation of end sections.


2019 ◽  
Vol 108 (1) ◽  
pp. 11-17
Author(s):  
Mert Şekerci ◽  
Hasan Özdoğan ◽  
Abdullah Kaplan

Abstract One of the methods used to treat different cancer diseases is the employment of therapeutic radioisotopes. Therefore, many clinical, theoretical and experimental studies are being carried out on those radioisotopes. In this study, the effects of level density models and gamma ray strength functions on the theoretical production cross-section calculations for the therapeutic radioisotopes 90Y, 153Sm, 169Er, 177Lu and 186Re in the (n,γ) route have been investigated. TALYS 1.9 code has been used by employing different level density models and gamma ray strength functions. The theoretically obtained data were compared with the experimental data taken from the literature. The results are presented graphically for better interpretation.


1981 ◽  
Vol 21 (06) ◽  
pp. 747-762 ◽  
Author(s):  
Karl E. Bennett ◽  
Craig H.K. Phelps ◽  
H. Ted Davis ◽  
L.E. Scriven

Abstract The phase behavior of microemulsions of brine, hydrocarbon, alcohol, and a pure alkyl aryl sulfonate-sodium 4-(1-heptylnonyl) benzenesulfonate (SHBS or Texas 1) was investigated as a function of the concentration of salt (NaCl, MgCl2, or CaCl2), the hydrocarbon (n-alkanes, octane to hexadecane), the alcohol (butyl and amyl isomers), the concentration of surfactant, and temperature. The phase behavior mimics that of similar systems with the commercial surfactant Witco TRS 10–80. The phase volumes follow published trends, though with exceptions.A mathematical framework is presented for modeling phase behavior in a manner consistent with the thermodynamically required critical tie lines and plait point progressions from the critical endpoints. Hand's scheme for modeling binodals and Pope and Nelson's approach to modeling the evolution of the surfactant-rich third phase are extended to satisfy these requirements.An examination of model-generated progressions of ternary phase diagrams enhances understanding of the experimental data and reveals correlations of relative phase volumes (volume uptakes) with location of the mixing point (overall composition) relative to the height of the three-phase region and the locations of the critical tie lines (critical endpoints and conjugate phases). The correlations account, on thermodynamic grounds, for cases in which the surfactant is present in more than one phase or the phase volumes change discontinuously, both cases being observed in the experimental study. Introduction The phase behavior of a surfactant-based micellar formulation is one of the major factors governing the displacement efficiency of any chemical flooding process employing that formulation. Knowledge of phase behavior is, thus, important for the interpretation of laboratory core floods, the design of flooding processes, and the evaluation of field tests. Phase behavior is connected intimately with other determinants of the flooding process, such as interfacial tension and viscosity. Since the number of equilibrium phases and their volumes and appearances are easier to measure and observe than phase compositions, viscosities, and interfacial tensions, there is great interest in understanding the phase-volume/phase-property relationships. Commercial surfactants, such as Witco TRS 10-80, are sulfonates of crude or partially refined oil. While they seem to be the most economically practicable surfactants for micellar flooding, their behavior, particularly with crude oils and reservoir brines, can be difficult to interpret, the phases varying with time and from batch to batch. Phase behavior studies with a small number of components, in conjunction with a theoretical understanding of phase behavior progressions, can aid in understanding more complex behavior. In particular, one can begin to appreciate which seemingly abnormal experimental observations (e.g., surfactant present in more than one phase or a discontinuity in phase volume trends) are merely features of certain regions of any phase diagram and which are peculiar to the specific crude oil or commercial surfactant used in the study.We report here experimental studies of the phase behavior of microemulsions of a pure sulfonate surfactant (Texas 1), a single normal alkane hydrocarbon, a simple brine, and a small amount of a suitable alcohol as cosurfactant or cosolvent. The controlled variables are hydrocarbon chain length, alcohol, salinity, salt type (NaCl, MgCl2, or CaCl2), surfactant purity, surfactant concentration, and temperature. Many of these experimental data were presented earlier. SPEJ P. 747^


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