scholarly journals Effect of design and kinematic parameters on energy requirement in inclined screw mixer

2019 ◽  
Vol 18 (4) ◽  
pp. 408-413
Author(s):  
V. F. Khlystunov ◽  
S. V. Braginets ◽  
A. S. Alferov ◽  
M. V. Chernutskiy

Introduction. Rational parameters and modes of an inclined batch screw mixer are validated to achieve the lowest energyintensive feed mixing under observance of the zootechnical requirements for the feed quality on uneven mixing. The establishment of functional dependences between parameters and modes enables to design power-efficient equipment for the on-farm feed production.Materials and Methods.Experimental studies of the feed mixing were implemented on an inclined screw batch feed mixer. The experimental design included variation of four independent factors: mixer shaft speed, filling ratio of the mixing chamber, mixing time, and mixing chamber angle. Mixing irregularity and energy intensity of the process were taken as optimization criteria characterizing the mixing efficiency.Research Results.The optimization criteria versus the variability level factor, which are two-dimensional sections of the second-order response surfaces, are plotted. The rational values at mixing irregularity of less than 5% were as follows: mixer shaft speed was 27.5-36.5 min-1 , filling ratio of the mixing chamber was 0.43–0.51, mixing time was 3.0–4.2 min, mixing chamber angle was 22°–25°. At such parameter values, the mixing irregularity will be minimal, and it will be 4.10– 4.18%, and the process intensity is from 2.08 to 2.16 kW • h/t.Discussion and Conclusions.The dependences obtained as a result of the experimental studies allowed establishing the domain of rational design parameters and modes of an inclined batch screw mixer. The results obtained can be used in further studies under the development of initial requirements for the creation of new technical means with a gravitation effect of intensive mixing.

Author(s):  
Salar Kartas ◽  
◽  
Vladimir Panchenko ◽  
Yury Aleksandrov ◽  
◽  
...  

The article presents the results of numerical simulations and experimental studies of a liquid-liquid ejector with a curved initial portion of the mixing chamber. The experiment was conducted on liquid-liquid ejectors, models of which are made on a 3D printer, by the method of layer-by-layer deposition. The influence of possible manufacturing errors of the ejector on its characteristics is estimated. The issues of the use of liquid ejectors designed to work in the field of various predetermined ejection coefficients are considered. The theoretical ejection coefficient and the reasons for reducing the ejection coefficient in real ejectors are determined. The obtained dependences make it possible to determine the optimal design parameters of a liquid ejector and thereby increase its ejection coefficient. The relative pressure drop is shown at a low coefficient and at a high ejection coefficient. The calculated and experimental results of determining the ejection coefficient for liquid ejectors, which are widely used in various fields of technology, are presented. The results of numerical simulation of internal processes in the ANSYS-Fluent hydro-gasdynamic application package flowing in a single-phase liquidliquid ejector based on the study of a small-sized model are presented. As a result of the simulation, a good agreement was obtained between the calculation results of the model corresponding to the real prototype and the experimental data and comparison with the results of other authors. Several conclusions can be drawn from the results of the study. For example, a region of values of the ejection coefficient was found in which the relative pressure drop created by the ejector increases with an increase in the ejection coefficient.


Author(s):  
A. B. Emelyanov ◽  
M. V. Kopylov ◽  
D. A. Kazartsev ◽  
M. K. Abrahamyan ◽  
M. V. Nechaev

The main objective of the experimental study of all processes is the analysis, study and generalization of all available results. In accordance with the idea of a step search, the experiment was carried out in several stages. The number of stages and actions at each of them depended on the results of the previous stage and the ultimate goal of research. The ultimate goal of the study is to determine the optimal conditions for the process of mixing the liquid aggregates to obtain a homogeneous structure. Studies of the mixing process were carried out on an experimental setup created at the department. To process experimental studies, the STATISTICA 12 software package was used. To obtain the regression equation, the matrix data were processed using the Microsoft Excel 2010 software package. To optimize the process, the output parameters were converted to a dimensionless scale of desirability d. It was established that the desirability function D, which characterizes the adequacy of the obtained values, has an extremum in experiment 12 and is 0.733666. Based on the obtained data, the following parameters should be considered optimal when mixing liquid aggregates: the peripheral speed of the mixer shaft is within 4 m/s, while the mixing time is 8 s and the refrigerant concentration is 20%.


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.


2021 ◽  
Vol 1037 ◽  
pp. 369-376
Author(s):  
Maxim Ilyushkin ◽  
Kirill Savelev ◽  
Oleg Krupennikov ◽  
Evgeniy S. Kiselev

The paper presents the results of numerical experimental studies of cutting titanium blanks using mathematical modeling programs, which make it possible to completely repeat technological processes in a computer (digital twin). The LS-DYNA product was used as a program to simulate the process of stock removal from titanium blank. It has been established that the use of this method adequately describes the cutting processes, including with the introduction of the energy of an ultrasonic field into the processing zone, can significantly reduce the duration of experimental research and evaluate the influence of the elements of the cutting mode and design parameters of the tool on the thermal power aspects of the formation of new surfaces of machine parts.


2021 ◽  
Vol 14 (4) ◽  
pp. 1-24
Author(s):  
Sushant Kafle ◽  
Becca Dingman ◽  
Matt Huenerfauth

There are style guidelines for authors who highlight important words in static text, e.g., bolded words in student textbooks, yet little research has investigated highlighting in dynamic texts, e.g., captions during educational videos for Deaf or Hard of Hearing (DHH) users. In our experimental study, DHH participants subjectively compared design parameters for caption highlighting, including: decoration (underlining vs. italicizing vs. boldfacing), granularity (sentence level vs. word level), and whether to highlight only the first occurrence of a repeating keyword. In partial contrast to recommendations in prior research, which had not been based on experimental studies with DHH users, we found that DHH participants preferred boldface, word-level highlighting in captions. Our empirical results provide guidance for the design of keyword highlighting during captioned videos for DHH users, especially in educational video genres.


Author(s):  
А.В. Панфилова ◽  
А.В. Королев ◽  
О.П. Решетникова ◽  
Б.М. Изнаиров ◽  
А.Н. Васин

Рассматриваются результаты проведения экспериментальных исследований способа удаления окалины с поверхности стального листового проката. Предложен новый способ и устройство для очистки поверхности листового проката от окалины режущими пластинами, вращающимися вокруг оси, перемещающейся поступательно вдоль обрабатываемой поверхности. Пластины наклонены в направлении вектора вращения на угол до 10 градусов и упруго поджимаются к обрабатываемой поверхности. Это обеспечивает возможность в процессе очистки поверхности воспроизводить макронеровности листового проката. Приведены результаты экспериментальных исследований, построены математические и графические зависимости, описывающие влияние факторов процесса на эффективность очистки поверхности проката. Показано, что наиболее значимое влияние на параметр оптимизации оказывает сила воздействия инструмента на поверхность заготовки. Причем это влияние реализуется в прямо пропорциональной зависимости. Другие исследованные факторы, а именно: угол наклона пластины, скорость ее вращения и подача, оказывают значительно меньшее влияние на степень очистки проката. Эти исследования были необходимы с точки зрения определения конструктивных параметров силовых элементов как технологической оснастки, реализующей указанный способ, так и технологической установки в целом. План эксперимента был принят, исходя из реальных производственных возможностей индустриального партнера, и соответствовал классическим представлениям теории резания. Описанные результаты дают возможность планировать дальнейшие эксперименты по изучению направлений использования данного способа Here we consider the results of experimental studies of the method of removing scale from the surface of steel sheet products. We propose a new method and device for cleaning the surface of rolled sheets from scale by cutting plates rotating around an axis moving translationally along the treated surface. The plates are tilted in the direction of the rotation vector at an angle of up to 10 degrees and are elastically pressed to the treated surface. This makes it possible to reproduce the macro-dimensions of sheet metal during the surface cleaning process. We present the results of experimental studies. We constructed mathematical and graphical dependences describing the influence of process factors on the efficiency of cleaning the rolled surface. We show that the most significant influence on the optimization parameter is exerted by the force of the tool's impact on the surface of the workpiece. Moreover, this influence is realized in a directly proportional relationship. Other factors studied, namely the angle of inclination of the plate, its rotation speed and feed, have a much smaller impact on the degree of cleaning of rolled products. These studies were necessary from the point of view of determining the design parameters of the power elements of both the technological equipment implementing this method and the technological installation as a whole. We adopted the experimental plan based on the real production capabilities of the industrial partner and corresponded to the classical concepts of the cutting theory. The described results make it possible to plan further experiments to study the directions of using the method


Author(s):  
Mandava Mohana Rao ◽  
Moutusi Paul ◽  
H.S. Jain

Fault-proof earthing switches are one of the important modules of a gas insulated substation, as it enables make at 100 percent short circuit current, which is functionally different from maintenance earthing switches. The fault-proof earthing switch shall be designed to make and break electro-magnetically and electro-statically induced currents as per IEC-62271-102. The paper discusses the impact of “test circuit configurations and voltage” on test parameters for gas insulated fault-proof earthing switch utilizing simulation with PSCAD software. Authors record the development of a 145 kV gas insulated fault proof earthing switch by considering novel design features like minimum arcing/pre-arcing time, effective current transfer from arcing contact to ground terminal, etc. The development has been evaluated successfully for electro-magnetically and electro-statically induced current duties as per IEC. Finally, design parameters to be considered for ensuring reliable performance during induced current switching from fault-proof earthing switches are also discussed.


Author(s):  
Jan Mihalyovics ◽  
Christian Brück ◽  
Dieter Peitsch ◽  
Ilias Vasilopoulos ◽  
Marcus Meyer

The objective of the presented work is to perform numerical and experimental studies on compressor stators. This paper presents the modification of a baseline stator design using numerical optimization resulting in a new 3D stator. The Rolls Royce in-house compressible flow solver HYDRA was employed to predict the 3D flow, solving the steady RANS equations with the Spalart-Allmaras turbulence model, and its corresponding discrete adjoint solver. The performance gradients with respect to the input design parameters were used to optimize the stator blade with respect to the total pressure loss over a prescribed incidence range, while additionally minimizing the flow deviation from the axial direction at the stator exit. Non-uniform profile boundary conditions, being derived from the experimental measurements, have been defined at the inlet of the CFD domain. The presented results show a remarkable decrease in the axial exit flow angle deviation and a minor decrease in the total pressure loss. Experiments were conducted on two compressor blade sets investigating the three-dimensional flow in an annular compressor stator cascade. Comparing the baseline flow of the 42° turning stator shows that the optimized stator design minimizes the secondary flow phenomena. The experimental investigation discusses the impact of steady flow conditions on each stator design while focusing on the comparison of the 3D optimized design to the baseline case. The flow conditions were investigated using five-hole probe pressure measurements in the wake of the blades. Furthermore, oil-flow visualization was applied to characterize flow phenomena. These experimental results are compared with the CFD calculations.


Author(s):  
Sergey Fedorovich Jatsun ◽  
Andrei Vasilevich Malchikov

This chapter describes various designs of multilink mobile robots intended to move inside the confined space of pipelines. The mathematical model that describes robot dynamics and controlled motion, which allows simulating different regimes of robot motion and determining design parameters of the device and its control system, is presented. The chapter contains the results of numerical simulations for different types of worm-like mobile robots. The experimental studies of the in-pipe robots prototypes and their analyses are presented in this chapter.


2020 ◽  
Vol 897 ◽  
pp. 106-110
Author(s):  
Alexey M. Lykov ◽  
Nataliya V. Mokrova

Experimental studies of plasma surface treatment processes of various materials are difficult since temperatures of the surface are more than 1500-3000 K, the speed of their change is high (104 K/s), the front of melting is moving. Theoretical researches of the thermal modes are necessary for conducting plasma processes in the best possible way. The use of analytical decisions at impulse thermal influence on the surface allows to calculate temperatures on the surfaces and in the mass of the material under almost any boundary conditions. The paper presents the results of calculation of various plasma processing at dielectric and steel materials (hardening, welding), as well as comparison of the obtained design parameters with experimental values.


Sign in / Sign up

Export Citation Format

Share Document