Thermophysics and Thermal Power Engineering最新文献

{"title":"MAIN CONCEPTUAL APPROACHES AND TECHNICAL SOLUTIONS OF THE HEAT SUPPLY SCHEME OF KYIV FOR THE PERIOD UNTIL 2030","authors":"A. Sigal, D. Paderno, N. A. Nizhnik","doi":"10.31472/ttpe.3.2021.5","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.5","url":null,"abstract":"The analysis of the district heating system of the city of Kyiv and its main operational indicators is presented. The main problems that need to be solved in the development of a new District Heating Scheme are described. The basic conceptual directions and technical decisions concerning development of system of heat supply of the city for the settlement period are resulted. As part of the development of the Heat Supply Scheme of Kyiv for the period up to 2030, a powerful heat source in the city center will be gradually converted to hydrogen fuel obtained from \"green\" energy by electrolysis (until the needs of ST-1 are fully met after 2030).","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72702362","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":"GLOBAL WARMING – PHYSICS AND GEOPOLITICS (Review) 3. Reduction of anthropogenic greenhouse gas emissions","authors":"B. Basok, Ye.T. Baseyev","doi":"10.31472/ttpe.3.2021.7","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.7","url":null,"abstract":"Introduction. Despite the global pandemic, reducing the negative effects of global warming and adapting to its devastating effects remains a pressing global problem. Its solution is actively taken care of by politicians, the world's leading scientific organizations and the expert community. \u0000Problems. Political, economic, innovative, scientific, technical and social approaches and measures to reduce and/or neutralize climate change and adapt to warming are widely discussed. World organizations - IPCC, IEA, WMO, etc. are involved in solving the problems. \u0000Goal. Assess the state of the problem, present the results of research and measures and tools for their implementation to reduce greenhouse gas emissions and/or adapt to their negative impact, in particular, in the energy sector - the largest producer of emissions. The main emphasis is on improving the energy efficiency of energy end-use, in particular, disseminating the experience of operational O&M (operation and maintenance) maintenance of passive buildings \"zero-energy\" in their energy supply from RES, as well as economic and financial leverage to reduce greenhouse gas emissions. \u0000Materials and methods. Authoritative recent literature sources with analysis of approaches, measures and tools to reduce greenhouse gas emissions are used. Weather-dependent (climatic) maintenance of the diagnostic-demonstration passive house of the \"zero-energy\" type with continuous system monitoring of parameters of engineering systems and building constructions and meteorological environment is organized. \u0000Results. Experience has been gained in the development and use of innovative energy-efficient technologies for energy supply of a demonstration passive house with O&M service by means of monitoring weather indicators and adaptation measures to climate change. \u0000Conclusions. The accumulated experience in the development of innovative energy efficient energy supply technologies and adaptation measures to climate change in O&M maintenance of zero-energy ITTF building of the NAS of Ukraine can be used in energy, in particular in municipal energy, and for the development of low-carbon energy. The use of approaches related to the taxation of excessive greenhouse gas emissions, or taking into account the decarbonization of the economy of production of goods and services in export-import operations, will also help reduce global warming.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78027815","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":"HEAT TRANSFER IN GRADIENT LAMINAR FLOWS","authors":"A. Avramenko, A.O. Tyrinov, N. P. Dmitrenko, Y. Kovetska","doi":"10.31472/ttpe.3.2021.4","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.4","url":null,"abstract":"The development of new areas of research in the field of theoretical thermophysics requires reliable analytical solutions that could take into account the main aspects of physical parameters in the studied objects. One such analytical technique is symmetry groups. \u0000On the basis of symmetry groups the problem of heat transfer in gradient laminar flows is solved in the paper. For the first time, the symmetries of the energy equation for the boundary layer at an arbitrary changing velocity at marching direction are obtained. Examples of the use of group analysis methods for the study of heat transfer in the boundary layer of an incompressible fluid are demonstrated. The problems of heat transfer in the boundary layer on a heat-conducting wall with a constant temperature and on a heat-insulated wall are considered. Analytical relations for temperature and heat transfer coefficients distribution are obtained.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85921731","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":"DRYING WHITE CABBAGE ON A CONVECTIVE DRYING BENCH","authors":"Zh. A. Petrova, V. Paziuk, P. Vishnevsky, D. Grakov, О. Grakov","doi":"10.31472/ttpe.3.2021.3","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.3","url":null,"abstract":"Known methods of production of dried cabbage are long-term production processes that take place within 12… 24 hours. Therefore, it is necessary to develop new methods of drying and intensification of this process. \u0000The article presents experimental studies of the kinetics of the drying process of white cabbage with different energy supply and their combinations, such as convective, infrared and convective-infrared drying methods. The main criterion for choosing a rational mode of drying is the quality of raw materials after heat treatment, in particular the visual assessment of color by temperature. \u0000During convective drying, the analysis of temperature regimes for process intensity and quality of raw materials was performed. The drying mode of 60ºC which satisfies all requirements for quality of material was chosen. To speed up the process, it is proposed to reduce the drying time by introducing a step mode of 80 / 60ºC, which also reduces the energy component. \u0000Infrared radiation intensifies the process due to the rapid heating of the material, but in turn it burns. Therefore, a combined convective-infrared method is proposed in which the temperature in the product did not exceed 60 ° C. This method of drying showed good results with a shorter drying time.Infrared radiation intensifies the process due to the rapid heating of the material, but in turn it burns. Therefore, a combined convective-infrared method is proposed in which the temperature in the product did not exceed 60 ° C. This method of drying showed good results with a shorter drying time.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86142755","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":"TEST OF A PILOT INSTALLATION OF A SOIL REGENERATOR FOR GREENHOUSES","authors":"I. Boshkova, N. Volgusheva, I. Mukminov, E. Altman","doi":"10.31472/ttpe.3.2021.11","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.11","url":null,"abstract":"The relevance of the development of ground regenerative heat exchangers is determined by the need to save energy resources for heating greenhouses at night and maintaining the required temperature level during the day. The aim of the work is to study working capacity of a ground regenerator for a greenhouse when testing a pilot plant in full-scale conditions. To achieve this goal the following main tasks were solved: experimental research of soil regenerator pilot plant operation was carried out, the heating period of nozzle and cooling period were determined by the obtained temperature curves, the coefficient of intercomponent heat exchange during the heating period was estimated, the rationality of material choice for granulated nozzle was proved, recommendations on improvement of soil regenerator design for industrial use were developed. The research was conducted on a pilot installation of a soil regenerator, which consists of a heat-exchange duct filled with granulated material and covered with a layer of insulation, and ducts with an exhaust duct fan installed at the outlet. Data on air and nozzle temperatures, which were taken during the day, were used to conduct thermal calculations and assess the efficiency of the ground regenerator. It was determined that the heating period at the selected loading mass of 15.5 kg is not long relative to the duration of the experiment and was 166 min. To increase the amount of accumulated heat it is recommended to increase the weight of the nozzle and air flow rate. It was determined that the coefficient of inter-component heat transfer during the heating period varied between 4 W/m2K and 9 W/m2K. In this case, the Bio number is in the range of 0.05 - 0.10, which allows us to conclude that the use of crushed stone as a nozzle material is rational. It is recommended to increase the thickness of insulation to 4.3 cm so that the heat loss from the heat exchange section does not exceed 5%, and to provide the installation of insulated plugs at the ends of the heat exchange section, closing after the end of the heating period.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83169957","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":"INFLUENCE OF THE POROUS MEDIA ON HEAT EXCHANGE AT FILM BOILING LIQUID","authors":"A. Avramenko, M. Kovetskaya, N. P. Dmitrenko, Y. Kovetska","doi":"10.31472/ttpe.3.2021.1","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.1","url":null,"abstract":"The present work focuses on a study of heat transfer during film boiling of a liquid on a vertical heated wall immersed in a porous medium subject to variation of different parameters of the porous medium and heating conditions at the wall. An analytical solution was obtained for the problem using Darcy-Brinkman-Forchheimer model. It was shown that heat transfer intensity during film boiling in a porous medium is weaker than in a free fluid (without porosity) and decreases with the decreasing permeability of the porous medium. \u0000The use of a porous medium model in the Darcy-Brinkman-Forchheimer approximation showed the effect of the Forchheimer parameter on heat transfer during film boiling in a porous medium. An increase in the Forchheimer parameter leads to heat transfer deterioration, which is more significant at small values of the Darcy number. Effects of different thermal boundary conditions on the heated wall on the heat transfer are insignificant.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88849013","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":"PROBLEMS OF BIOMASS ASH UTILIZATION FROM BOILER HOUSES IN UKRAINE","authors":"V. Kramar","doi":"10.31472/ttpe.3.2021.9","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.9","url":null,"abstract":"As  result of the study, it was estimated that in 2019 in Ukraine  the annual biomass ash formation to be utilized, amounted to 132 thousand tons, and in the future, subject to the goals of bioenergy development, it may increase almost 10 times until 2050. The main way to treat biomass ash in Ukraine is to bury it in landfills, partly use in landfills as an insulating material, and partly as fertilizer, mainly in homesteads. In Ukraine, the widespread use of biomass ash is limited by the lack of legal requirements for its utilization, absence of technical requirements for its use in the construction industry, complex procedure of state registration of pesticides and agrochemicals, which puts biomass ash in unequal competitition with the mineral fertilizers. Also, a certain barrier to the use of biomass ash as a fertilizer is its physical and chemical characteristics, which require special methods of its application. The increase in useful utilization of ash requires field research of its effectiveness as a fertilizer, development of different types of fertilizers based on biomass ash for different types of soils and crops and methods of their use with proven efficiency, development of the most efficient utilization methods of the ash, which does not meet the requirements of its use in agriculture, in other industries.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75254344","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":"FEATURES OF SPATIAL DISTRIBUTION OF THE SPECIFIC HEAT CAPACITY OF SUPERCRITICAL WATER DURING ITS FLOW IN VERTICAL BARE TUBES","authors":"N. Fialko, A.V. Nosovsksyi, S.O. Aleshko, I. Pioro, D. Khmil","doi":"10.31472/ttpe.3.2021.2","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.2","url":null,"abstract":"The results of computer modeling of the spatial distribution of the specific heat capacity under condition of the upstream flow of supercritical water in vertical bare tubes are given. The features of the motion along the tube length the front of the pseudo-phase transition \"pseudoliquid-pseudogas\" are considered. The position of this front determines the location of the extremums of the specific heat capacity of water. The regularities of changes in the radial distributions of heat capacity along the length of the tube and longitudinal distributions for different values of the radial coordinate are investigated. The data of a comparative analysis of this distribution at various values of the specific heat flux supplied to the tube wall are presented","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74124654","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":"PROSPECTS OF BIOMETHANE PRODUCTION IN UKRAINE","authors":"G. Geletukha, Yu. B. Matveev","doi":"10.31472/ttpe.3.2021.8","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.8","url":null,"abstract":"Biogas upgrading to quality of natural gas (NG) creates possibility to supply biomethane to the NG grid, easy transportation and production of electricity and heat in locations where there is guaranteed consumption of thermal energy. Biomethane as a close NG analogue can be used for heat and electricity production, as soon as motor fuel and raw material for chemical industry. \u0000The International Energy Agency (IEA) estimates that the world's annual biomethane production potential is 730 bcm (20% of current world's NG consumption). World biomethane production reached almost 5 bcm/yr in 2019. According to forecast of the European Biogas Association the biogas and biomethane sector may almost double its production by 2030. According to IEA estimates, annual world biomethane production could reach 200 bcm in 2040 in case the sustainable development strategy is implemented \u0000Currently, the Bioenergy Association of Ukraine estimates the potential for biogas/biomethane production in Ukraine using fermentation technology as 7,8 bcm/yr (25% of the country's current NG consumption). The roadmap of bioenergy development in Ukraine until 2050 envisages growth of biomethane production to 1,7 bcm in 2035 and up to 3 bcm in 2050. \u0000Currently the prospects for green hydrogen development are well known. The authors support the need of hydrogen technologies as one of the way for production and use of renewable gases. However, they believe that biomethane has no less prospects. \u0000Transporting of one cubic meter of biomethane through gas pipeline at 60 bar pressure transmits almost four times more energy than transporting of one cubic meter of hydrogen. This is fundamental advantage of biomethane. Another advantage is the full readiness of gas infrastructure for biomethane. Given the cost of gas infrastructure modernization to use hydrogen, it is more cost-effective to convert green hydrogen to synthetic methane. \u0000Currently, biomethane is in average three times cheaper than green hydrogen, the cost of the two renewable gases is expected to equalize by 2050, and only further possible reduction in the cost of green hydrogen below $2/kg will make green hydrogen cheaper than biomethane. Therefore, the greatest prospects can be seen in the combination of the advantages of both renewable gases and conversion of green hydrogen into synthetic methane (power-to-gas process). \u0000Authors believe that after adoption of legislation to support the development of biomethane production and use in Ukraine, the bulk of biomethane produced in the country will be exported to EU, where more favourable conditions for biomethane consumption are developed. As Ukraine's economy grows, more and more of the biomethane produced will be used for domestic consumption.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"2 5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87649598","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":"PROSPECTS FOR DECARBONIZATION OF DISTRICT HEATING IN UKRAINE","authors":"G. Geletukha, T. Zheliezna, A. Bashtovyi","doi":"10.31472/ttpe.3.2021.6","DOIUrl":"https://doi.org/10.31472/ttpe.3.2021.6","url":null,"abstract":"The purpose of the work is to determine promising areas for decarbonization of district heating in Ukraine, as well as measures necessary for their practical implementation. State of the development of bioenergy in the world and in the EU is presented, and considerable contribution of bioenergy to the production of renewable heat is emphasized. In Ukraine, the existing problems of long-term planning at the state and regional levels in the heat supply sector need to be addressed. Recommendations for solving these problems have been developed. One of them is the elaboration of the Heat Supply Strategy until 2035, built on the principle of the Energy Strategy of Ukraine, as well as the Action Plan for its implementation. It is recommended to introduce the term “efficient district heating” in the legislation of Ukraine, which corresponds to Directive 2012/27/EU on energy efficiency, and to declare the purpose of increasing the share of such systems in district heating. The role of bioenergy in the process of decarbonization of district heating of Ukraine is analyzed. It is shown that one of the ways that can significantly improve the situation in heat supply is the wide involvement of biomass and solid biofuels in this sector. For the effective implementation of this task it is necessary to launch an electronic trade system for solid biofuels (biofuel exchange), introduce competition in district heating systems, as well as perform a set of additional actions and measures. This will allow not only to stabilize the situation with heat supply in Ukraine, but also to reduce the heat tariff for end users by 15-20%.","PeriodicalId":23079,"journal":{"name":"Thermophysics and Thermal Power Engineering","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86765531","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}