Thermophysics and Thermal Power Engineering最新文献

{"title":"THE COMPUTER SIMULATION OF THE COMBUSTION OF THE GASIFICATION PRODUCTS IN FLUIDIZED BED OF SOLID FUEL IN UPPER BED LAYER WITH VORTEX BURNING","authors":"S. Kobzar, G. Kovalenko, A. Khalatov","doi":"10.31472/ttpe.2.2021.9","DOIUrl":"https://doi.org/10.31472/ttpe.2.2021.9","url":null,"abstract":"The swirl afterburning is a promising method of improving the combustion of solid fuels. \u0000The aim of the work is to verify the ANSYS CFX software package for calculating the vortex chamber of cyclone-ball furnaces afterburning. \u0000As a result of the study it was determined that to simulate the combustion of gasification products of solid fuel in a fluidized bed in a upper bed space with vortex afterburning, it is advisable to use a two-stage mechanism of methane oxidation, supplemented by hydrogen oxidation reaction. The parameters of the Eddy Dissipation model are determined, which allow obtaining results on temperature fields and fields of concentrations of the main components with satisfactory accuracy, both qualitatively and quantitatively.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84378547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IMPLEMENTATION OF THE DРIE METHOD IN TECHNOLOGIES OF OBTAINING STRUCTURED SYSTEMS","authors":"O. Obodovich, T. Grabova, D. V. Posunko, R. E. Bazieiev","doi":"10.31472/ttpe.2.2021.2","DOIUrl":"https://doi.org/10.31472/ttpe.2.2021.2","url":null,"abstract":"Within the framework of the work, experimental and laboratory studies of a complex of heat and mass transfer processes in multicomponent disperse systems that exhibit emergent properties have been carried out. \u0000The aim of the work is to determine the key factors that affect the properties of the final product, and bifurcation points for complex dispersed systems in terms of the mechanisms of structure formation. \u0000The authors determined the influence of key parameters such as the process temperature and shear stresses that arise in systems during processing in rotary-pulsating devices of the disk-cylindrical type. \u0000For systems with polyelectrolyte structures, the temperature ranges have been determined at which the intensity of the solvation process is maximum. \u0000The investigated multicomponent systems are sensitive to shear stress and the duration of its exposure. The limiting shear stresses are determined at which the destruction of structures begins and the system becomes fluid. \u0000Based on the results of the complex of works, a schematic diagram and a pilot plant for obtaining poly-component structured systems were proposed. Вatches of bactericidal sanitary-hygienic means and application medical-prophylactic means were obtained at the proposed installation and transferred for testing.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"70 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83919174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MODELS AND MEASURESIN THEORY AND PRACTICE OF MEASUREMENTS","authors":"V. Babak, A. A. Zaporozhets, Y. Kuts, L. Scherbak","doi":"10.31472/TTPE.4.2020.1","DOIUrl":"https://doi.org/10.31472/TTPE.4.2020.1","url":null,"abstract":"It is known that deterministic and probabilistic models of measured quantities, processes and fields, as well as physical and probabilistic measures, make it possible to form a measurement result, to provide it with the properties of objectivity and reliability. On their basis, the measuring instruments necessary for obtaining new knowledge and maintaining the process of technological development of production are being developed and improved. Therefore, the issues of improving and developing models and measures in measurement methodology play an increasingly important role in achieving high measurement accuracy and expanding the areas of their application. The article is devoted to the features and results of the study of the application of models and measures in measurements. \u0000It is shown that the physical correctness and the need for setting up measuring experiments, performing tasks and conditions for their implementation, substantiating adequate models and measures significantly affect the obtained measurement result. The features of the modern methodology of using models of signals and fields and measures for evaluating the results of measuring physical quantities, including thermophysical ones, which are represented by random quantities and angles are presented. In the general case, a measure is a countably additive set function that acquires only negative values ​​in any way, including infinity. The use of charge as a mathematical model significantly expands the boundaries of the practical application of the methods of measure theory in metrology. Examples of probabilistic measures on a straight line, on a circle and a charge, as well as physical measures are considered. The concept of coordination of physical and probabilistic measures has been substantiated with the aim of a unified approach to assessing the measurement result. The joint use of physical and probabilistic measures for the formation of a measurement result allows to a certain extent overcome the problem of measurement homomorphism. An example of using a set of physical and probabilistic measures in the hardware and software modules of information and measuring systems is given. The probabilistic normalized measure is a non-physical degree, but a measure of the totality of the action of various random factors on the value and characteristics of data and the result of measurements when they are carried out. The use of a probabilistic measure in the statistical processing of measurement data makes it possible to increase the accuracy of the measurement result compared to the accuracy of the measurement data. \u0000The degree of information protection during measurements is complex. The measure is formed by many factors, the action of most of which is of a random nature. This makes it possible to determine such a measure as probabilistic, which can be applied both for individual operations, for example, transmission of measurement data via communication channels, registration of t","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75153955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"APPLICATION OF MODERN PRE-INSULATED PIPES TO INCREASE THE ENERGY EFFICIENCY OF CENTRALIZED HEAT SUPPLY SYSTEMS","authors":"I. Bozhko","doi":"10.31472/TTPE.4.2020.9","DOIUrl":"https://doi.org/10.31472/TTPE.4.2020.9","url":null,"abstract":"The article is devoted to a review of manufacturing technologies and methods for counteracting the effects of aging and destruction of a ball of thermal insulation in previously insulated pipes (PIP) of heating networks. The thermophysical characteristics of various blowing agents are compared; the superiority of cyclopentane in both thermophysical and environmental parameters is shown. \u0000The basic technologies for the production of pre-insulated pipe wires are considered. The advantages of «conti» technology using a diffusion barrier are highlighted. It is shown that for polyurethane foam, the main factor that suppresses heat transfer through PUR type thermal insulation is the low thermal conductivity of the gas mixture, which is \"sealed\" in the foam cells. \u0000The analysis of the influence of “aging” of the heat-insulating shell, namely, the diffusion of oxygen molecules into the structure of polyurethane foam, is carried out, and its negative effect on the thermal characteristics of the heat-insulating material is shown. Oxygen diffusion leads to a gradual increase in the value of the coefficient of thermal conductivity of the heat-insulating shell, and as a result, increases heat loss by the pipeline. The results of predictive calculations confirmed the effectiveness of the use of diffusion barriers in the manufacture of PIP. It is shown that when using PIP with a diffusion barrier, unproductive heat energy losses decrease on average by 20–21%, which, in turn, leads to a decrease in the amount of payments to end consumers and an increase in the quality and efficiency of district heating systems. \u0000It is also noted that polymer pre-insulated pipelines are practically not inferior in strength and reliability to steel PIP and at the same time, they have several advantages over steel PIP. It is recommended to increase the use of polymer PIP in the reconstruction of heating networks of the district heating system.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83138528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EXERGIC EFFICIENCY OF THE HEAT RECOVERY UNIT FOR WASTE GASES OF A HEAT ENGINE OF A COGENERATION PLANT","authors":"N. Fialko, A. Stepanova, R. Navrodskaya, S. Shevchuk","doi":"10.31472/ttpe.3.2020.6","DOIUrl":"https://doi.org/10.31472/ttpe.3.2020.6","url":null,"abstract":"The paper presents the results of a study of the efficiency of a heat recovery unit for waste gases of a heat engine of a cogeneration plant. The possibilities of using for this purpose the discrete-modular principle and complex methods of analyzing the efficiency of heat recovery systems, which are based on the methods of exergo-dissipative functions and exergic balances, are analyzed. The design features of the heat exchanger are considered and a conclusion is made about the possibility of presenting it as a system of eight discrete modules. The results of calculating the exergy characteristics for each of the eight heat exchanger modules, performed within the framework of the indicated methods, are presented. A regular decrease in exergy losses and heat-exergy criterion of efficiency is observed during the transition from the first to the eighth module of the heat recovery unit. However, exergy characteristics for the third and fourth modules of the heat exchanger are somewhat higher than the indicated dependence suggests. This indicates the thermodynamic imperfection of these modules. The main exergy losses in all heat exchanger modules are associated with losses due to heat transfer from flue gases to the wall. An insignificant discrepancy between the values ​​of the total exergy losses calculated within the framework of the methods used indicates that both methods can be used in various heat recovery schemes. However, in each specific case, it is necessary to choose a methodology with which it is possible to identify individual elements that need optimization or constructive improvement. Particular attention is paid to the comparative analysis of the selected techniques and consideration of the advantages and disadvantages of their use in various cases. It is noted that the technique based on the integral balance method of exergy analysis can be considered effective due to the small number of initial parameters and the simplicity of the analytical and calculation methods. The advantage of the technique using exergo-dissipative functions is that it allows one to differentiate exergy losses in a heat exchanger and establish the causes and areas of their localization.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89373170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALYSIS OF WAYS FOR DECARBONIZATION OF THE EU HEATING SECTOR (REVIEW)","authors":"T. Zheliezna, A. I. Bashtovyi","doi":"10.31472/TTPE.4.2020.11","DOIUrl":"https://doi.org/10.31472/TTPE.4.2020.11","url":null,"abstract":"The aim of the work is to analyze possible ways of decarbonization of the EU heat supply sector. The task of the work is to identify the most promising areas and develop appropriate recommendations for Ukraine. The heat supply sector of the EU and Ukraine needs decarbonization, for which there is a big potential and different areas of implementation of relevant measures. In Europe, such a strategy is set out in the Roadmap for decarbonization of the EU heating sector until 2050, the main provisions of which are in line with objectives of the European Green Deal and the EU Strategy on Heating and Cooling. European experts have developed the concept of a smart energy system, which was taken into account when preparing the Roadmap for decarbonization of the EU heating sector until 2050. A number of carried out studies have shown that a smart energy system with 50% district heating integrated with other parts of the overall energy system is more efficient than a conventional energy system or the one based on decentralized heat supply, in terms of the possibility of using a high share of renewable energy. It is recommended for Ukraine to finalize the Concept of green energy transition until 2050, taking into account European approaches to the development of heating systems and the use of modern biofuels. It is also recommended to expand the current Concept of heat supply of Ukraine to the level of a strategy with an emphasis on the development of district heating systems, wide involvement of renewable energy sources and new technologies.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86458075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALYSIS OF DIRECTIONS OF USING SUNFLOWER PRODUCTION BY-PRODUCTS FOR ENERGY IN UKRAINE (REVIEW)","authors":"G. Geletukha, S. Drahniev, T. Zheliezna, A. Bashtovyi","doi":"10.31472/TTPE.4.2020.10","DOIUrl":"https://doi.org/10.31472/TTPE.4.2020.10","url":null,"abstract":"The aim of the work is to analyze technical and economic basis for the development of energy and biofuel production from sunflower growing by-products in Ukraine. The task of the work is to determine conditions that ensure the economic feasibility of such type projects in Ukraine. Results of assessment of the energy potential of sunflower production by-products in Ukraine are presented. Ukraine is a world leader in terms of sunflower gross harvest. Consequently the country has a large potential of by-products from sunflower growing and processing available for energy. Today, with the exception of sunflower husk, this type of biomass is practically not used for energy needs. Small amounts of sunflower growing by-products are mainly used by some agricultural producers and rural households to cover their own needs in heat. Taking into consideration the insufficiently described practice of harvesting this type of biomass and the undoubted prospects of its use for energy in Ukraine, it is necessary to conduct some field tests of harvesting technologies, at least on the basis of existing agricultural machinery, in particular, forage harvester and mulcher with a baler. Further research is needed on the technology of direct combustion of stalks and other by-products of sunflower growing, as well as the production of solid, liquid and gaseous biofuels from them.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86231790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TECHNOLOGIES, SYSTEMS, AND EQUIPMENT FOR WASTEWATER HEAT UTILIZATION (REVIEW)","authors":"B. Basok, M. Novitska, S. Goncharuk","doi":"10.31472/ttpe.3.2020.4","DOIUrl":"https://doi.org/10.31472/ttpe.3.2020.4","url":null,"abstract":"The paper analyzes research, technologies, and equipment related to wastewater heat utilization systems. The main factors influencing the development of the industry and the implementation of such systems are given. Such factors include: social, political, economic, technological, legal and environmental. The classification of technologies and equipment for wastewater heat utilization according to the place of heat extraction is given. Namely, low potential wastewater heat can be collected at the treatment plants, in sewer collectors leading to treatment plants and directly in houses. The paper describes the available research in the scientific literature on these three categories The global scientific community is working to create efficient wastewater heat recovery systems. The environmental situation requires greater use of wastewater recovery systems. An important issue is to increase awareness and education of the population, as this approach will increase the degree of implementation of wastewater heat utilization systems in residential buildings.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88899964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALYSIS OF BARRIERS TO THE PRODUCTION OF ENERGY FROM AGROBIOMASS IN UKRAINE. PART 2","authors":"G. Geletukha, T. Zheliezna, S. Drahniev, A. Bashtovyi","doi":"10.31472/ttpe.4.2019.6","DOIUrl":"https://doi.org/10.31472/ttpe.4.2019.6","url":null,"abstract":"The aim of the work is to identify and analyze barriers to the production of energy from agribiomass in Ukraine. For better analyzing, the barriers are grouped according to different categories. The task of the work is to develop recommendations to overcome the identified and described barriers. In this part of the article, organizational, legislative, economic and environmental barriers to the use of biomass of agrarian origin for energy in Ukraine are considered. It is shown that applying a balanced and rational approach, it is possible to use part of the residues and by-products of crop production for energy. To reduce the negative impact on the soil, it is necessary to return ash from the burning of agribiomass to the fields, as well as introduce a sufficient amount of organic and mineral fertilizers. In order to stop the practice of unauthorized burning of crop remains in fields, it is recommended to create conditions under which harvesting and sale of biomass for energy will be economically attractive. One of such measures could be the introduction of biofuel electronic trade system in Ukraine. The draft law required for the establishment and operation of such a system was prepared in 2018 with the participation of the Bioenergy Association of Ukraine. It is also necessary to develop a strategy for the use of biomass of agricultural origin for energy and include it in one of the existing national documents or to approve it as a separate document. Another option is to elaborate a strategy for bioenergy development in Ukraine with a separate section on agribiomass. Dedicated ministries should explicitly state in their official documents their views on the possibility and optimal volumes of the use of agribiomass for energy production. This can be done, for example, by developing \"Recommendations regarding possible volumes of crop production by-products to be used for energy in Ukraine\".","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78723386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CFD SIMULATION OF TEMPERATURE REGIMES OF THE COMBUSTION ZONE OF STABILIZER-TYPE BURNERS WITH ASYMMETRIC FUEL SUPPLY","authors":"N. Fialko, V. Prokopov, Ju.V. Sherenkovskyi, S. Alioshko, N. Meranova, K. V. Rokytrko","doi":"10.31472/ttpe.4.2019.2","DOIUrl":"https://doi.org/10.31472/ttpe.4.2019.2","url":null,"abstract":"The results of computer simulation of the heat state of the combustion zone and the burnup rate of fuel for stabilizer burners with asymmetric fuel distribution are presented. The features of temperature fields in this zone that are characteristic of the conditions under study are revealed. The analysis of these features in the aspect of their conditionality by the two-stage combustion of fuel gas is carried out.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88534165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}