The technique of the processes of investigating of convective heat transfer determining in the problems of icing of aerodynamic surfaces on the basis of the solution of the Reynolds-averaged Navier- Stokes equations and the one-parameter Spalart-Allmaras turbulence differential model with correction for a rough wall is presented. A methodology that allowed to simulate airfoils icing processes taking into account the ice surface roughness is presented. For the description of the external air-droplet flow a model of interpenetrating media was used. For the description of the ice growing process the method of surface control volumes using the methodology of determining the convective heat transfer based on the solution of the Navier-Stokes equations and the one-parameter differential Spalart-Allmaras turbulence model with a correction for a rough wall were used. Verification was performed by comparing the calculations results with the data obtained with the help of known semiempirical relationships. The proposed approach, unlike existing methods, will allow us to begin solving problems in a three-dimensional statement, with a rather complex geometry, in the presence of transonic regions in the airflow, and also to determine the aerodynamic characteristics of streamlined bodies with rough ice accretions. References 15, figures 3.
{"title":"NUMERICAL INVESTIGATION OF THE INFLUENCE OF SURFACE ROUGHNESS ON CONVECTIVE HEAT TRANSFER AT AIRFOIL ICING PROCESS","authors":"A. Prykhodko, S. Alekseyenko","doi":"10.31472/IHE.2.2018.09","DOIUrl":"https://doi.org/10.31472/IHE.2.2018.09","url":null,"abstract":"The technique of the processes of investigating of convective heat transfer determining in the problems of icing of aerodynamic surfaces on the basis of the solution of the Reynolds-averaged Navier- Stokes equations and the one-parameter Spalart-Allmaras turbulence differential model with correction for a rough wall is presented. \u0000A methodology that allowed to simulate airfoils icing processes taking into account the ice surface roughness is presented. For the description of the external air-droplet flow a model of interpenetrating media was used. For the description of the ice growing process the method of surface control volumes using the methodology of determining the convective heat transfer based on the solution of the Navier-Stokes equations and the one-parameter differential Spalart-Allmaras turbulence model with a correction for a rough wall were used. Verification was performed by comparing the calculations results with the data obtained with the help of known semiempirical relationships. The proposed approach, unlike existing methods, will allow us to begin solving problems in a three-dimensional statement, with a rather complex geometry, in the presence of transonic regions in the airflow, and also to determine the aerodynamic characteristics of streamlined bodies with rough ice accretions. References 15, figures 3.","PeriodicalId":133229,"journal":{"name":"Industrial Heat Engineering","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127761865","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}
The results of experimental studies of humidity, ash content, calorific value for сomponents of municipal solid waste in Cherkassy city are presented. The results of the research are used to develop an integrated waste management and recycling system in the Cherkassy city. The waste management strategy has been adopted in Ukraine. It determines the main directions of reforming the system of sanitary cleaning of cities in order to minimize environmental pollution in accordance with EU standards. In the process of preparation of the regional implementation plan for the Strategy in Cherkassy, a study of the morphology, energy and environmental characteristics of the components of solid domestic waste (SDW) was made. This article presents the results of experimental studies of humidity, calorific value and ash content for 8 components of waste: paper, cardboard, composite materials, textiles, hygiene products, plastic, other combustible materials, wood shavings are presented. Humidity is also determined in organic residues and in fine fractions. The investigations were carried out at the experimental stand of the Institute of Technical Thermophysics of the National Academy of Sciences of Ukraine. Due to the absence in Ukraine of standards for the study of energy characteristics of solid waste, the measurements were carried out in accordance with standards for solid organic fuels, which slightly differ from the EU methods for the study of solid waste. In order to develop regional integrated waste management plans within the framework of the strategy implementation, based on the qualitative analysis of MSW components, it is necessary to develop standards for determining the energy characteristics of SDW in line with European normative documents. The study of the energy characteristics of solid waste showed a significant heterogeneity in the components of solid waste, which significantly complicated the determination of characteristics and led to a considerable scatter of results and an increase in measurement uncertainty. This happened due to low weight and the need for thorough homogenization of the sample, which was experimentally investigated in accordance with the method of preparation of an analytical sample. The article analyzes need for adaptation of the European methods of detailed morphology of solid domestic waste in Ukraine, which is necessary for separate waste collection. The results of the research are used to develop an integrated waste management and recycling system in the city of Cherkassy.
{"title":"ANALYSIS OF THE ENERGY CHARACTERISTICS OF COMPONENTS OF MUNICIPAL SOLID WASTE OF A CITY WITH A POPULATION OF 300 000 PEOPLE","authors":"O. Sigal, L. Vorobiov, N. Pavliuk, R. Serhiienko","doi":"10.31472/IHE.2.2018.05","DOIUrl":"https://doi.org/10.31472/IHE.2.2018.05","url":null,"abstract":"The results of experimental studies of humidity, ash content, calorific value for сomponents of municipal solid waste in Cherkassy city are presented. The results of the research are used to develop an integrated waste management and recycling system in the Cherkassy city. \u0000The waste management strategy has been adopted in Ukraine. It determines the main directions of reforming the system of sanitary cleaning of cities in order to minimize environmental pollution in accordance with EU standards. In the process of preparation of the regional implementation plan for the Strategy in Cherkassy, a study of the morphology, energy and environmental characteristics of the components of solid domestic waste (SDW) was made. \u0000This article presents the results of experimental studies of humidity, calorific value and ash content for 8 components of waste: paper, cardboard, composite materials, textiles, hygiene products, plastic, other combustible materials, wood shavings are presented. Humidity is also determined in organic residues and in fine fractions. \u0000The investigations were carried out at the experimental stand of the Institute of Technical Thermophysics of the National Academy of Sciences of Ukraine. \u0000Due to the absence in Ukraine of standards for the study of energy characteristics of solid waste, the measurements were carried out in accordance with standards for solid organic fuels, which slightly differ from the EU methods for the study of solid waste. In order to develop regional integrated waste management plans within the framework of the strategy implementation, based on the qualitative analysis of MSW components, it is necessary to develop standards for determining the energy characteristics of SDW in line with European normative documents. \u0000The study of the energy characteristics of solid waste showed a significant heterogeneity in the components of solid waste, which significantly complicated the determination of characteristics and led to a considerable scatter of results and an increase in measurement uncertainty. This happened due to low weight and the need for thorough homogenization of the sample, which was experimentally investigated in accordance with the method of preparation of an analytical sample. \u0000The article analyzes need for adaptation of the European methods of detailed morphology of solid domestic waste in Ukraine, which is necessary for separate waste collection. \u0000The results of the research are used to develop an integrated waste management and recycling system in the city of Cherkassy.","PeriodicalId":133229,"journal":{"name":"Industrial Heat Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128457381","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}
An experimental study of the ratio of cumulants of acoustic signals of fluid leakage in a pipeline and interference is carried out. It is shown that the use of bandpass filtering increases the ratio of cumulants by orders of magnitude. The purpose of the article is to analyze the sensitivity of the cumulant method of detecting fluid leaks in a pipeline based on the statistical processing of the acoustic leakage signal and interference generated by the moving fluid flow. To analyze the possibilities of a cumulant leak detection method, it is necessary to have specific values of cumulants of real leakage signals and interference, which can be obtained as a result of a full-scale experiment. To generate a leakage signal, an installation is used that allows physical modeling of the leakage of liquid in the pipe in standing water. To simulate a leak in a pipe, a nozzle with copper walls and a through hole with a diameter of 1 mm was used, and a pressure of 6 atmospheres was maintained to produce leakages in the pipe. As a interference, noise generated by a moving fluid flow in the pipeline is used. The interference was recorded on the pipeline of the distribution network at a pressure of 7 atmospheres, the volume flow of the coolant averaged more than 1000 liters per hour, which ensured the flow rate of the fluid at which its motion can be considered turbulent. The results of experimental studies of acoustic signals of fluid leakage in the pipeline and interference showed that the main interference power is concentrated in the 0...5 kHz band, and the leakage signal is in the band 5...10 kHz. With the use of bandpass filtering, the ratio of the mean square deviation of the leakage signals and interference increased by more than an order of magnitude for the frequency bands 5...10 kHz and 10...15 kHz, as compared with the absence of filtering. In this case, the ratio of the absolute values of the cumulants of the leakage signal and the interference is much greater than the ratio of the variances, and the ratio of cumulants increases substantially with increasing order. This confirms the sensitivity of high-order cumulants to the presence of a leak.
{"title":"ANALYSIS OF THE INFLUENCE OF FILTRATION ON THE SENSITIVITY OF THE CUMULANT METHOD OF DETECTING THE ACOUSTIC SIGNALS OF LEAKAGE","authors":"V. Beregun, A. Krasilnikov, T. Polobyuk","doi":"10.31472/IHE.2.2018.11","DOIUrl":"https://doi.org/10.31472/IHE.2.2018.11","url":null,"abstract":"An experimental study of the ratio of cumulants of acoustic signals of fluid leakage in a pipeline and interference is carried out. It is shown that the use of bandpass filtering increases the ratio of cumulants by orders of magnitude. \u0000The purpose of the article is to analyze the sensitivity of the cumulant method of detecting fluid leaks in a pipeline based on the statistical processing of the acoustic leakage signal and interference generated by the moving fluid flow. To analyze the possibilities of a cumulant leak detection method, it is necessary to have specific values of cumulants of real leakage signals and interference, which can be obtained as a result of a full-scale experiment. \u0000To generate a leakage signal, an installation is used that allows physical modeling of the leakage of liquid in the pipe in standing water. To simulate a leak in a pipe, a nozzle with copper walls and a through hole with a diameter of 1 mm was used, and a pressure of 6 atmospheres was maintained to produce leakages in the pipe. As a interference, noise generated by a moving fluid flow in the pipeline is used. The interference was recorded on the pipeline of the distribution network at a pressure of 7 atmospheres, the volume flow of the coolant averaged more than 1000 liters per hour, which ensured the flow rate of the fluid at which its motion can be considered turbulent. \u0000The results of experimental studies of acoustic signals of fluid leakage in the pipeline and interference showed that the main interference power is concentrated in the 0...5 kHz band, and the leakage signal is in the band 5...10 kHz. With the use of bandpass filtering, the ratio of the mean square deviation of the leakage signals and interference increased by more than an order of magnitude for the frequency bands 5...10 kHz and 10...15 kHz, as compared with the absence of filtering. In this case, the ratio of the absolute values of the cumulants of the leakage signal and the interference is much greater than the ratio of the variances, and the ratio of cumulants increases substantially with increasing order. This confirms the sensitivity of high-order cumulants to the presence of a leak.","PeriodicalId":133229,"journal":{"name":"Industrial Heat Engineering","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123994540","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}
Technology of conservation of thermal energy is perspective direction for the modern systems of thermal and cold supply. To hire the methods of calculation of transfer of warmth and mass, results of experimental researches, are driven and drawn conclusion about financial viability of application of different substances for creation of mobile thermal accumulators. A review of the research of heat accumulators for the system of heat and cold supply is presented. An analysis of theoretical and experimental data on determining the geometric characteristics of the battery for the required amount of heat and cold, depending on the area of premises. Depending on the thermophysical properties of the heataccumulating material, it is possible to significantly reduce the volume of the heat accumulator by using thermal accumulators with a phase transition. The TAM study showed that bischofite-based batteries require 29.7 m3 for the accumulation of 1,0 MWh of heat, while for trihydrate sodium acetate will be spent only 17.4 m3. Implementation of discrete systems of heat and cold supply will create a vertically integrated energy holding company based in each region to generate cheap heat energy and coolant.
{"title":"MOBILE ACCUMULATORS FOR DISCRETE SYSTEMS HEAT-COLD SUPPLIES. Part 1","authors":"V. Demchenko, V. Falko, S. Hron","doi":"10.31472/IHE.2.2018.03","DOIUrl":"https://doi.org/10.31472/IHE.2.2018.03","url":null,"abstract":"Technology of conservation of thermal energy is perspective direction for the modern systems of thermal and cold supply. To hire the methods of calculation of transfer of warmth and mass, results of experimental researches, are driven and drawn conclusion about financial viability of application of different substances for creation of mobile thermal accumulators. \u0000A review of the research of heat accumulators for the system of heat and cold supply is presented. An analysis of theoretical and experimental data on determining the geometric characteristics of the battery for the required amount of heat and cold, depending on the area of premises. Depending on the thermophysical properties of the heataccumulating material, it is possible to significantly reduce the volume of the heat accumulator by using thermal accumulators with a phase transition. The TAM study showed that bischofite-based batteries require 29.7 m3 for the accumulation of 1,0 MWh of heat, while for trihydrate sodium acetate will be spent only 17.4 m3. Implementation of discrete systems of heat and cold supply will create a vertically integrated energy holding company based in each region to generate cheap heat energy and coolant.","PeriodicalId":133229,"journal":{"name":"Industrial Heat Engineering","volume":"9 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126100903","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}
The results of the life cycle assessment of heat production from willow chips of Salix Viminalis L. are presented. Energy efficiency and greenhouse gas emissions reduction are estimated. The influence of the most significant parameters is analyzed and optimal relationships are determined to ensure maximum energy efficiency and environmental sustainability. The purpose of the paper is to define the energy efficiency and environmental sustainability of bioenergy value chain for heat production from willow chips of Salix Viminalis in Ukraine. The methodology of Life Cycle Assessment (LCA) was used, according to which, the scope of the product system includes the feedstock cycle of willow Salix Viminalis L. cultivation and harvest, and the subsystem of willow chips conversion to heat in a 500 kW biomass boiler. Cumulative energy demand and energy yield coefficient were chosen as energy efficiency indicators. The product system was compared with the similar one using natural gas. Non- renewable energy yield coefficient was used to define how many times the energy output was bigger than input of non- renewable energy. An acceptable value for renewable energy installations and systems is to receive twice as much energy output as was spent of non-renewable energy, however the recommended value assumed in the work is to receive a 5 times more energy output compared to non-renewable energy input. As an environmental sustainability indicator, a reduction of GHG emissions was used. The acceptable level of GHG emissions reduction was chosen at a level of 60% for the whole life cycle from cultivation-to-heat, compared to traditional heat production in gas boilers. Results of the assessment identified that the most significant parameter affecting energy efficiency and environmental sustainability is transportation distance. The growing of willow Salix Viminalis L. in Ukraine for the subsequent production of biofuel in the form of chips and its combustion in biofuel boilers is environmentally sustainable with a maximum transportation distance of 390 km and energy efficient with a maximum transportation distance of 180 km.
{"title":"LIFE CYCLE ASSESSMENT OF HEAT PRODUCTION FROM WILLOW CHIPS OF SALIX VIMINALIS L. IN UKRAINE","authors":"O. Tryboi","doi":"10.31472/ihe.2.2018.08","DOIUrl":"https://doi.org/10.31472/ihe.2.2018.08","url":null,"abstract":"The results of the life cycle assessment of heat production from willow chips of Salix Viminalis L. are presented. Energy efficiency and greenhouse gas emissions reduction are estimated. The influence of the most significant parameters is analyzed and optimal relationships are determined to ensure maximum energy efficiency and environmental sustainability. \u0000The purpose of the paper is to define the energy efficiency and environmental sustainability of bioenergy value chain for heat production from willow chips of Salix Viminalis in Ukraine. The methodology of Life Cycle Assessment (LCA) was used, according to which, the scope of the product system includes the feedstock cycle of willow Salix Viminalis L. cultivation and harvest, and the subsystem of willow chips conversion to heat in a 500 kW biomass boiler. Cumulative energy demand and energy yield coefficient were chosen as energy efficiency indicators. The product system was compared with the similar one using natural gas. Non- renewable energy yield coefficient was used to define how many times the energy output was bigger than input of non- renewable energy. An acceptable value for renewable energy installations and systems is to receive twice as much energy output as was spent of non-renewable energy, however the recommended value assumed in the work is to receive a 5 times more energy output compared to non-renewable energy input. As an environmental sustainability indicator, a reduction of GHG emissions was used. The acceptable level of GHG emissions reduction was chosen at a level of 60% for the whole life cycle from cultivation-to-heat, compared to traditional heat production in gas boilers. Results of the assessment identified that the most significant parameter affecting energy efficiency and environmental sustainability is transportation distance. The growing of willow Salix Viminalis L. in Ukraine for the subsequent production of biofuel in the form of chips and its combustion in biofuel boilers is environmentally sustainable with a maximum transportation distance of 390 km and energy efficient with a maximum transportation distance of 180 km.","PeriodicalId":133229,"journal":{"name":"Industrial Heat Engineering","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124347299","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}