scholarly journals Natural research of the thermal process on the surface of irradiation by infrared heater

2021 ◽  
Vol 31 (1) ◽  
pp. 85-88
Author(s):  
Н. А. Сподинюк ◽  
В. Б. Шепітчак
Keyword(s):  
Methodological Approach ◽  
Thermal Power ◽  
Experimental Studies ◽  
Mathematical Methods ◽  
Relative Temperature ◽  
Experimental Data Processing ◽  
Entire Area ◽  
Floor Surface ◽  
Infrared Heater ◽  
Production Facilities

Comfortable conditions for people to stay in the production room with the use of infrared emitters depend on the uniform distribution of temperatures over the entire area of the irradiation zone. Therefore, the purpose of the research was to determine experimentally the temperature on the irradiation surface with an infrared heater and to summarize the results, for their further use in the design of infrared heaters in various production facilities. The distribution of temperatures on the irradiation surface was determined by the method of experimental studies. To derive the patterns of temperature field distribution on the irradiation surface, the experiment was carried out at variable power of the infrared heater Qheat, W, the height of its installation H, m and different blackness degrees of the floor surface εfloor, which depends on the floor material. The graphical distribution can prove the regularity of that heat in solid materials is distributed due to thermal conductivity – from particles with higher temperatures to less heated. Using mathematical methods of experimental data processing, experimental dependences were approximated to determine the relative temperature of the irradiation surface. The temperature gradient obtained graphically is directed along the normal to the isothermal surface in the direction of increasing temperature. This approach enables considering the development of process in the dynamics and allows the visualization of heating to adjust the basic parameters of process. Scientific results obtained in this work will allow developing a new methodological approach to the study of heating processes on the surface of irradiation by an infrared heater on the basis of a combination of physical and mathematical modeling, which can form an instrumental basis for the target study of such processes of formation of the thermal regime in production facilities. The thermal power of the infrared heater Qheat, W had the greatest influence on the value of the relative temperature of the floor surface tfloor. With constant values of the height of the heater, the blackness degree of the irradiation surface and with increasing the thermal power of the heater twice the value of the relative temperature of the irradiation surface increased by 9.7 %.

scholarly journals Calculation of infrared heating burners of a micronizer using biomethane

2020 ◽  
Vol 82 (1) ◽  
pp. 17-26
Author(s):  
V. A. Afanasyev ◽  
A. N. Ostrikov ◽  
I. S. Bogomolov ◽  
D. A. Nesterov ◽  
P. V. Filiptsov
Keyword(s):  
Carbon Dioxide ◽  
Control System ◽  
Water Vapor ◽  
Natural Gas ◽  
Infrared Radiation ◽  
Thermal Power ◽  
Experimental Studies ◽  
Infrared Heating ◽  
Entire Area ◽  
Radiation Burners

Studies have been carried out on the purification of biogas from sulfur compounds, carbon dioxide and water vapor for subsequent use in micronizer burners. The possibility of bringing it to the parameters of natural gas of the following composition: methane (CH4) – 85 % vol., carbon dioxide СО2 – 11 % vol., water vapor – 9 mg/m3, hydrogen sulfide H2S - 20 mg/m3 with minimal energy costs for its preparation is demonstrated. The basic relationships are obtained for assessing the design and technological parameters of the infrared radiation burners operation. Experimental studies of the flame stability limits on perforated ceramic nozzles have shown that flashback through them is possible when the thermal power is increased to a certain critical value. In this case, the thermal power depends on the type of gas and the air content in the combustible mixture. The heat balance equations have been derived to optimize the designs and operation modes of infrared radiation burners. The design of 40 gas burners was improved by changing the geometric dimensions and shape for a uniform distribution of biogas supplied and sustainable combustion over the entire area of the burner. It was established that the temperature of the heating surface of the GIK-8 burner on gas mixtures with a CO2 content of 18-34 % is 900-950 ° C, which does not differ from the nominal temperature when operating on natural gas. The infrared heating system was modernized, adapted for burning purified biogas with methane content up to 98 %, in particular, the biomethane feed and control system, the additional biogas input system, and the automatic burner control system were improved.

The methodology of experimental research of the feed components extrusion process in order to improve its energy performance

2020 ◽  
pp. 147-152
Author(s):  
E. M. Ratnikov ◽  
D. O. Milko
Keyword(s):  
Experimental Studies ◽  
Energy Performance ◽  
Extrusion Process ◽  
Mathematical Methods ◽  
Screw Extruder ◽  
Mathematical Planning ◽  
Factors Affecting ◽  
Extrusion Processing ◽  
Definition Of

Annotation Purpose. Development of a program and methods for conducting experimental studies of the extrusion process with the definition of parameters and modes of operation of the extruder to improve its energy performance. Methods. Methods of mathematical statistics, synthesis, analysis, description and modeling were used. Results. The application of mathematical methods, in particular mathematical planning, reduces the number of experiments several times, and allows to evaluate the role of influencing factors, obtain a mathematical model of the process and determine the optimal conditions for its parameters and modes, etc. Conclusions. The methodology for experimental studies of a screw extruder is presented with the necessary equipment and methodology for processing the obtained experimental data. A mathematical method of planning, which reduces the number of experiments several times, allows us to evaluate the role of factors affecting productivity and energy intensity is presented. Keywords: extruder, auger, nutrients, research methodology, extrusion, processing, feed.

scholarly journals Improvement Dependability of Offshore Horizontal-Axis Wind Turbines by Applying New Mathematical Methods for Calculation the Excess Speed in Case of Wind Gusts

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3085
Author(s):  
Konstantin Osintsev ◽  
Seregei Aliukov ◽  
Alexander Shishkov
Keyword(s):  
Computer Simulation ◽  
Wind Turbines ◽  
Experimental Studies ◽  
Offshore Wind ◽  
Approximation Schemes ◽  
Calculation Error ◽  
Strong Wind ◽  
Mathematical Methods ◽  
Wind Gusts ◽  
Gas Dynamic

The problem of increasing the reliability of wind turbines exists in the development of new offshore oil and natural gas fields. Reducing emergency situations is necessary due to the autonomous operation of drilling rigs and bulk seaports in the subarctic and Arctic climate. The relevance of the topic is linked with the development of a methodology for theoretical and practical studies of gas dynamics when gas flows in a pipe, based on a mathematical model using new mathematical methods for calculation of excess speeds in case of wind gusts. Problems in the operation of offshore wind turbines arise with storm gusts of wind, which is comparable to the wave movement of the gas flow. Thus, the scientific problem of increasing the reliability of wind turbines in conditions of strong wind gusts is solved. The authors indicate a gross error in the calculations when approximating through the use of the Fourier series. The obtained results will allow us to solve one of the essential problems of modeling at this stage of its development, namely: to reduce the calculation time and the adequacy of the model built for similar installations and devices. Experimental studies of gas-dynamic flows are carried out on the example of a physical model of a wind turbine. In addition, a computer simulation of the gas-dynamic flow process was carried out. The use of new approximation schemes in processing the results of experiments and computer simulation can reduce the calculation error by 1.2 percent.

Use of Digital Twins for Mathematical Modeling of Ultrasonic Cutting of Titanium Blanks

2021 ◽  
Vol 1037 ◽  
pp. 369-376
Author(s):  
Maxim Ilyushkin ◽  
Kirill Savelev ◽  
Oleg Krupennikov ◽  
Evgeniy S. Kiselev
Keyword(s):  
Mathematical Modeling ◽  
Thermal Power ◽  
Experimental Studies ◽  
Ultrasonic Field ◽  
Design Parameters ◽  
Digital Twins ◽  
Machine Parts ◽  
Cutting Processes ◽  
Stock Removal ◽  
Processing Zone

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.

Experimental Study on Various Mineral Admixtures in Fibre Reinforced Concrete

2019 ◽  
pp. 309-317
Author(s):  
Kavitha E ◽  
Karthik S ◽  
Eithya B ◽  
Seenirajan M
Keyword(s):  
Fly Ash ◽  
Rice Husk ◽  
Power Plants ◽  
Rice Husk Ash ◽  
Thermal Power ◽  
Experimental Studies ◽  
Mineral Admixtures ◽  
Hardened Concrete ◽  
Polypropylene Fibres ◽  
Concrete Production

The quantity of fly ash produced from thermal power plants in India is approximately 80 million tons each year, and its percentage utilization is less than 10%. An attempt has been made to utilize these cheaper materials in concrete production. This thesis aims at investigating the characteristics of fresh concrete and various strengths of hardened concrete made with various mineral admixtures such as fly ash. GGBFS, silica fume. Rice husk ash along with polypropylene fibres in various proportions.  M20 grade concrete is considered for experimental studies with 53grade Ordinary Portland Cement blended with varying percentages of mineral admixtures. The maximum size of coarse aggregate used is 20mm.  Various mineral admixtures such as fly ash. GGBFS.Silica fume. Rice Husk Ash were added concrete in various percentages by partially replacing cement and the optimum percentage of the mineral admixtures will be found.  Based on the obtained values, the admixture with maximum mechanical strength is determined and to this polypropylene fibre is added by varying 0 to 0.5 % by weight of cement to the mix.  The test results obtained were compared and discussed with conventional concrete.

scholarly journals Environmental Characteristics of Modern Systems of Domestic Use of Fuel. Part 2. Pollutants Formation by Natural Gas Combustion in Atmospheric Burners: Experimental Studies

2020 ◽  
Vol 63 (5) ◽  
pp. 450-461
Author(s):  
B. S. Soroka ◽  
V. V. Horupa
Keyword(s):  
Thermal Power ◽  
Experimental Studies ◽  
Environmental Indicators ◽  
Gas Pressure ◽  
Operating Conditions ◽  
National Academy Of Sciences ◽  
High Concentration ◽  
Hydrocarbon Gases ◽  
Absolute Level ◽  
Toxic Emissions

The Gas Institute of the National Academy of Sciences of Ukraine performs comprehensive studies of the formation of toxic emissions in the flame of atmospheric burners and beyond the visible burning cones (“rich” primary flame). The experiments are based on the proven significant content of harmful substances in the combustion products of gas fuel in household appliances and on direct contact of consumers with gas emissions during the operation of the stoves. A methodology for the experimental researches of the harmful emissions formation has been proposed while the computerized firing rig serving as the diagnostic facility has been developed for studying the combustion of hydrocarbon gases in the burners of household stoves. Carbon oxides CO and nitrogen oxides NO and NO2 are considered as toxic emissions, while the primary air excess coefficient and the heat load of the burner are considered as variable parameters. Under operating conditions of a gas stove, its variable characteristics are the gas pressure in front of the nozzle of the atmospheric burner and its thermal power. When optimizing the design of burners, the determinant value of the stability of burning, energy and environmental indicators of fuel combustion is the coefficient of excess of primary air λpr at a given gas pressure before the burner. The influence of this coefficient on the formation of CO, NO, NO2 is established, and the possibility of emissions with a high concentration of nitrogen dioxide is proved. Since the concentration of [NO] decreases with an increase in λpr, and the absolute level of [NO2] concentrations is not significantly affected by the value of λpr, it is determined that the proportion of [NO2] concentration in the [NOx] = [NO] + [NO2] compound increases with an increase in the primary air excess coefficient.

scholarly journals EXPERIMENTAL FACILITY FOR THE STUDY OF THE PROCESSES IN MIXING LOW-PRESSURE HEATERS OF K-1000-60/3000 TURBINES

2020 ◽  
Vol 2 (61) ◽  
pp. 42-50
Author(s):  
A. Smychok ◽  
◽  
V. Gerliga ◽  
V. Zaporozhan ◽  
M. Panchenko ◽  
...  
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Experimental Studies ◽  
Operating Experience ◽  
Low Pressure ◽  
Main Task ◽  
Experimental Facility ◽  
Design Features ◽  
Technical Problems ◽  
Hydraulic Processes

Nowadays, the development of nuclear energy is determined by solving the set of scientific and technical problems that provides reliable, safe and sustainable work of the operated and designed NPPs. At the same time different accident conditions and likelihood (probability) of variant equipment operating failures are analyzed. Obtained operating experience of the mixing low-pressure heaters (LPH) at thermal power plants (TPP) and NPPs shows that pulsations occur in some operation regimes of LPH turbine which lead to inner element destructions of LPH and pipeline malfunctions. These circumstances negatively affect operation of equipment that locates after LPH in condensate-supply tract. Consequently, unit capacity factor and economic indicators descend since troubleshooting for LPH mechanisms require some time and material resources. This work presents the experimental facility design and description of main design features of the facility components. The stand was designed to study the processes that lead to the vibration appearance in mixing LPH in condensate-supply tract of K-1000-60/3000 turbines. The main task of scale modeling is the need to observe equivalent conditions of the thermal-hydraulic processes behavior in the model in relation to full-scale equipment. To solve this problem using ANSYS code a preliminary simulation of hydraulic processes occurring in the experimental facility was performed. This allowed to determine in advance certain design features in the design of given facility. The results of experimental studies of the developed facility should allow to develop measures for reduction or complete elimination of vibrations in mixing LPH, as well as to validate computer programs for design analysis of stationary and non-stationary thermal-hydraulic processes in the specified equipment and designed measures testing.

Diagnostics of Advanced Power Intensive Power Sources Based on the Acoustic Spectroscopy Method

2021 ◽  
pp. 121-127
Author(s):  
E.M. Petrenko ◽  
V.A. Semenova
Keyword(s):  
High Reliability ◽  
Methodological Approach ◽  
Spectral Characteristics ◽  
Experimental Studies ◽  
Mechanical Action ◽  
Mean Value ◽  
Spectroscopy Method ◽  
Power Sources ◽  
Acoustic Spectroscopy ◽  
Noise Diagnostics

Objective of this article is to develop a method for lithium chemical current sources diagnostics, which would ensure high reliability in assessing their technical state (primarily, the discharge degree) close to potentially achievable introduction of the acoustic spectroscopy method. Today, microcalorimetric studies and methods of impedance and noise spectroscopy make it possible to predict the lithium chemical current sources service life. However, implementation of the microcalorimetric studies result requires a lot of time accompanied by using stationary and large-size equipment, which is practically impossible in the autonomous conditions. Application of the impedance spectroscopy method provides satisfactory results only with high degrees of discharge. In the range of 0--30 %, it is very difficult to determine the discharge degree, since noticeable alteration in the correlate within its deviation from the mean value is missing. In this regard, it is proposed in order to provide diagnostics of the lithium chemical current sources in the region of initial degrees of discharge to introduce the noise diagnostics method. In order to increase reliability of the diagnostic estimates, it is advisable to use acoustic spectroscopy as a physically independent method in diagnosing the state of lithium chemical current sources. Results of the preliminary measurements analysis confirm the prospects of using the acoustic spectroscopy method in assessing the current state of primary lithium chemical current sources. Experimental studies of the lithium chemical current sources response to acoustic (mechanical) action made it possible to determine a set of parameters characterizing the proposed methodological approach. This provided a possibility to search for correlation dependences of the lithium chemical current sources spectral characteristics on the degree of their discharge. This makes it possible to use the method of acoustic spectroscopy in prompt and reliable diagnostics of the primary current sources in the region of low discharge degrees

Using compatibility charts to optimize research into fire retardants

2021 ◽  
Vol 29 (6) ◽  
pp. 40-49
Author(s):  
T. Yu. Eremina ◽  
D. A. Korolchenko ◽  
F. A. Portnov
Keyword(s):  
Research Methods ◽  
Interdisciplinary Research ◽  
Building Materials ◽  
Design Research ◽  
Methodological Approach ◽  
Experimental Studies ◽  
Assessment Method ◽  
Material Research ◽  
Fire Retardants ◽  
Interdisciplinary Methods

Introduction. Interdisciplinary research is a most relevant issue in science and education. The integration of intellectual resources with research and production infrastructure is acknowledged as the main goal of interdisciplinary research in the international practice. The main (analytical) part. The authors propose the following methodological approach to the study, based on the distribution of interdisciplinary methods into groups by the scale of the research subject (material). In this case, the studies have the following levels: microlevel, supramolecular level, material research, design research. The paper presents research methods used at each of these levels. The co-authors propose to optimize the study of performance characteristics of building materials and fire retardants through the use of a compatibility chart with regard for the study levels and the analysis of methods of experimental research at each level. Using a compatibility chart. The methodology of the study. A research into the fire retardant efficiency of esters of phosphoric acid, used to modify wood, was selected as a practical example for compatibility diagrams. The project encompasses a number of methods applicable to compatibility charts: the method of elemental analysis, the Gibbs energy assessment method, the sample surface assessment method, the electron microscopy method, methods of assessing fire-hazardous characteristics of wood, the water sorption method, strength and biosecurity assessment methods. Conclusions. The co-authors first proposed an algorithm for generalizing the empirical data on mechanochemical characteristics of materials using interdisciplinary methods in the form of a compatibility chart. This methodology optimizes research into any composite materials though it preserves targeted research methods and eliminates impractical and concomitant experimental studies, thus, reducing labour costs and environmental impacts.

scholarly journals Lime Treatment of Coal Bottom Ash for Use in Road Pavements: Application to El Jadida Zone in Morocco

Materials ◽  
2019 ◽  
Vol 12 (17) ◽  
pp. 2674 ◽  
Author(s):  
Souad El Moudni El Alami ◽  
Raja Moussaoui ◽  
Mohamed Monkade ◽  
Khaled Lahlou ◽  
Navid Hasheminejad ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Low Cost ◽  
Thermal Power ◽  
Experimental Studies ◽  
Bottom Ash ◽  
Coal Ash ◽  
Road Construction ◽  
Dry Density ◽  
Second Phase ◽  
Lime Treatment

Industrial waste causes environmental, economic, and social problems. In Morocco, the Jorf Lasfar Thermal Power Station produces two types of coal ash with enormous quantities: fly ash (FA) and Bottom ash (BA). FA is recovered in cement while BA is stored in landfills. To reduce the effects of BA disposal in landfills, several experimental studies have tested the possibility of their recovery in the road construction, especially as a subbase. In the first phase of this study, the BA underwent a physicochemical and geotechnical characterization. The results obtained show that the BA should be treated to improve its mechanical properties. The most commonly used materials are lime and cement. In the selected low-cost treatment, which is the subject of the second phase of the study, lime is used to improve the low pozzolanicity of BA while calcarenite sand is used to increase the compactness. Several mixtures containing BA, lime, and calcarenite sand were prepared. Each of these mixtures was compacted in modified Proctor molds and then subjected to a series of tests to study the following characteristics: compressive strength, dry and wet California Bearing Ratio (CBR), dry density and swelling. The composition of each mixture was based on an experimental design approach. The results show that the values of the compressive strength, the dry density, and the CBR index have increased after treatment, potentially leading to a valorization of the treated BA for use in a subbase.

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