Ventilation, Illumination and Heat Gas Supply最新文献

{"title":"Simulation of heat transfer at the junction of the attic floor to the building envelope","authors":"G. Ratushnyak, O. Horiun, A. Lialiukk","doi":"10.32347/2409-2606.2020.35.26-33","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.35.26-33","url":null,"abstract":"Numerous studies and thermal imaging inspection of multi-storey residential buildings indicate characteristic places with increased heat loss. In houses built in accordance with modern domestic regulatory requirements for the thermal resistance of enclosing structures, the actual thermal resistance of walls and windows coincides with the standard. However, nodes of elements of external enclosing structures with increased values of heat loss were found. Insulation of the junction points allows increasing the thermal resistance of the external enclosing structures. In order to increase the energy efficiency of a building, the design of the insulation of the junction of the ceiling in the technical attic has been proposed, which is protected by a patent for a useful model. The linear heat transfer coefficients of the junction point of the ceiling in the attic are analyzed. It was revealed that such information was not indicated in the regulatory documents. Reducing heat loss is achieved by arranging additional layers of insulation in the form of aerogel slabs at the junction of the ceiling to the external enclosing structures. The analysis of the energy efficiency of the proposed design of the junction unit of the attic floor as a \"cold bridge\" was carried out according to the results of mathematical modeling in the DAMWERK software package. Based on the simulation results, the temperature distribution in the junction of the ceiling in the technical attic was established. The linear heat transfer coefficient of the recommended junction point of the ceiling in the technical attic has been determined, the value of which should be taken into account when developing the Energy Efficiency section. The results obtained confirm the feasibility of introducing the proposed structural design of the floor abutment unit in the technical attic, which will improve the energy efficiency of the building's thermal insulation envelope.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"69 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72663680","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":"Impact Assessment of the ventilation systems on microbiological safety and microclimatic conditions of premises","authors":"Tetiana Kryvomaz, Dmytro Varavin, Rostyslav Sipakov, R. Kuzmishina","doi":"10.32347/2409-2606.2020.35.49-61","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.35.49-61","url":null,"abstract":"The critical aspects of the impact of microbiological contamination on ventilation and air conditioning systems, the microclimate of the premises, and human health are analyzed. The quantitative and qualitative composition of the microflora of premises depends on their functional purpose, design features, operating conditions, climate, and other factors, among which the method of ventilation is essential. The moisturizers in air conditioning system are hazardous, which provide bacteria and fungi with water necessary for their life and reproduction. In addition, contaminants accumulated in ventilation systems operate as a substrate for feeding microorganisms. Multi-story administrative, public and residential buildings, industrial buildings, and other places of mass concentration are areas of increased aerobiological risk of infection. In case of improper operation, air conditioning and ventilation systems can be sources of microorganisms in any room. Transmission of infectious aerosol over long distances occurs in rooms with poor ventilation, and a key factor for the outbreak of infection is the direction of airflows. In the context of the COVID-19 pandemic, organizations and international agencies to control the spread of SARS-CoV-2 indoors recommend limiting the operation of exhaust ventilation and recirculation systems. However, there is still insufficient data to clarify the role of heating, ventilation, and air conditioning systems in spreading infection. Risk assessment and decision-making on the choice of air conditioning systems should be dynamic and based on the scale of the pandemic and the verification of the characteristics of HVAC systems and their effectiveness.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90323115","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":"Numerical simulation and study of thermal characteristics of a lightweight floor heating system","authors":"B. Basok, M. Novitska, S. Goncharuk","doi":"10.32347/2409-2606.2020.35.15-20","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.35.15-20","url":null,"abstract":"The use of underfloor heating systems is an effective way to achieve thermal comfort for users in energy-efficient buildings. There are two kinds of such systems: traditional and dry-assembled. The first type is researched more deeply than the second one. The paper presents theoretical studies of the thermotechnical parameters of a water underfloor dry-assembled heating system. The design of the underfloor dry-assembled heating system, considered in the work, consists of a heat insulation (expanded polystyrene), on which the pipes of the heating system are located, in contact with an aluminum heat distribution plate. The system is covered with floor finishing. The calculation for a stationary operating mode of the floor heating system was carried out on the basis of a system of equations for momentum and energy. The model was validated using the results of experimental studies. The calculation results cause some overestimation of the experimental data, possibly, beecause of deviations in thermotechnical characteristics of materials. But the simulation model correctly estimates the behaviour of the system at change of its parameters. The paper concludes that this configuration of the underfloor heating system can be used in heating systems for residential and non-residential premises. The aluminum heat distribution plate significantly affects the heat transfer processes in the system. Due to the plate, the heat flux is made uniform in the plane of the floor surface, which has a positive effect on heat distribution and reduces thermal tension in the finish coating. The use of ceramic tiles increases the overall heat exchange efficiency of the system with the room air. An increase in the thickness of the expanded polystyrene board increases the value of the heat flux from the surface of the heated floor. An increase in the flow rate and temperature of the heat carrier also cause an increase in the density of heat flux from the floor surface.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"15 1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75583807","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":"Combined scheme of solid fuel combustion in low power boilers","authors":"M. Senchuk","doi":"10.32347/2409-2606.2020.35.6-14","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.35.6-14","url":null,"abstract":"Different constructive schemes of solid fuel combustion in heating boilers up to 100 kW with the analysis of their efficiency depending on the quality of the burned solid fuel are considered. It is established that low-power solid fuel boilers with various types of combustion devices depending on the characteristics of the burned fuel and the accepted level of service are used in heat supply systems of premises, buildings and structures: from simple furnaces with manual maintenance to automated combustion devices of complex design. Mostly pre-prepared high-quality fuel is used for combustion: fuel pellets, briquettes, high-quality coal, the high cost of which significantly increases operating costs. In order to reduce capital and operating costs, it is advisable to introduce relatively inexpensive models of low-power heating boilers with an acceptable level of mechanization of combustion technology of cheap fuel, including local, with minimal costs for its preparation. The design of a heating water boiler with a semi-mechanical furnace and a technological scheme of combustion is proposed, which combines the processes of drying, gasification and combustion of fuel in a shaft with a clamping grate and combustion of coke in a layer on a moving grate. It is noted that the periodic supply of fuel in the furnace with a moving grate is maintained the stability of the combustion process in the combustion chamber, in the period between cleaning of ash and slag, without significant changes in the composition of above-layer gases. Due to the smooth movement of the next portion of hot coke from the fuel shaft to the combustion chamber on the rotating grate, conditions are created to maintain the uniformity of the boiler with the normative indicators. A reduction in harmful emissions in the exhaust gases was achieved during the combustion of the reaction fuel by passing a secondary blast of air through a collector and directing it to the combustion zone of light substances at the outlet of the clamping grate. Analytical equations for determining the size of the combustion zone according to the regime and design parameters of the combustion process are given. The efficiency of application of the combined (shaft-layer) technological scheme in low-power boilers was tested during testing of combustion of different quality coal in a semi-mechanical furnace with a rotating grate in the electric coal boiler with a heat output of 50 kW for railway carriages.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78440713","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":"Reducing the Impact of Pollution on Heating Surfaces in Low-Power Solid Fuel Heat Generators","authors":"M. Senchuk, A. Rybka, O. Yurko","doi":"10.32347/2409-2606.2020.0.15-21","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.0.15-21","url":null,"abstract":". The research of providing thermal efficiency of convective surfaces in heating solid fuel boilers by periodically cleaning them has been performed in the article. Various factors that influence the degree of contamination of heat exchange surfaces, which are flushed by the combustion products, are analysed. Possibilities of decreasing their negative impact are shown. The construction of heat generators with low heat production, which convective packs mainly provide one- or two-way horizontal motion of flue gases, have the problem of increase the contamination of surfaces, especially when the intensity of the combustion process is changing. Low frequency of cleaning led to the trouble following trouble. Initial loose contaminants, which are easily cleanable, transform into dense formations. Therefore, it is difficult to achieve the required surface cleanliness and, accordingly, an acceptable coefficient of thermal efficiency. The inefficiency and complexity of manual cleaning and the feasibility of using mechanized cleaning of convective surfaces of heating solid fuel boilers of low thermal efficiency have been substantiated. The constructive scheme of solid fuel heat generator with mech-anical cleaning of a vertical tubular convective package by combined turbulizers of special design are de-scribed. A comparative analysis of the economical efficiency of the solid fuel boiler with a heat output of 0.63 MW are carried out. The operating efficiency will increase by 0,6…1,4 % dependent on the actual heat load. Accordingly, the fuel amount and the air pollution by flue gases will decrease. The frequency of cleaning of convective surfaces with mechanized devices is increased, which ensures the uniformity of the existing heat load during long operation. The introduction of this class of boiler equipment is promising in the municipal en-ergy sector to reduce the complexity of servicing and saving fuel resources.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85625305","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":"The Concept of Multidisciplinary Study of the Aesthetic, Psychological and Physiological Impact of Chromatic Light Environment on a Person","authors":"L. Koval","doi":"10.32347/2409-2606.2020.0.47-62","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.0.47-62","url":null,"abstract":"","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82357265","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":"In-Depth Exergoeconomic Analysis as an Effective Tool for the Development of Energy-Efficient Circuit Solutions in Air-Conditioning Systems (for Example, a Membrane Air Dehumidification System for Seed Storage Premises)","authors":"O. Zadoiannyi, Y. Yevdokymenko","doi":"10.32347/2409-2606.2020.0.44-55","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.0.44-55","url":null,"abstract":". The paper presents a method of in-depth exergoeconomic analysis, as well as an example of its application to select the most energy-efficient method of air dehumidification for storing agricultural products, namely pumpkin seeds. Theoretical dependences are presented for determining the exergy components of moist airflow (thermal, humidity and mechanical, as well as full exergy). The formulas and the methodology for determining the exergy efficiency “net\", which reflects only the internal thermodynamic transformations of air in the air-conditioning system and the exergy efficiency “gross\", taking into account the amount of exergy from external sources are given. For a visual representation of the calculations and analysis of exergy destruction in the air conditioning systems, exergy flow diagrams are constructed. The results of calculations of the costs of processing air in an air conditioning system are presented in the form of streaming accumulative diagrams. Based on the results of analysis and comparison of exergoeconomic costs, a scheme with combined membrane dehumidification of air was selected to ensure the necessary storage conditions. Еxergy efficiency “net\" for an air handling unit with combined membrane dehumidification of air is 16 % higher than exergy efficiency “net\" for an air handling unit with condensing air drying, and 48 % more than exergy efficiency “net\" for an air handling unit with adsorption method of air drying. Еxergy efficiency “gross\" for an air handling unit with combined membrane air drying 43.5 % more than exergy efficiency “gross\" for an air handling unit with condensing air drying, and 54.6 % more exergy efficiency “gross\" for an air handling unit with adsorption air drying. In addition, according to in-depth exergoeconomic analysis, the cost of air treatment in air conditioning systems is halved.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89088256","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":"Development of a Method for Heating Room Indoor Microclimate Study which Includes Thermophysical Modelling and Experimental Data","authors":"O. Priimak, Nikita Ocheretianko, A. Vintoniv","doi":"10.32347/2409-2606.2020.0.17-23","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.0.17-23","url":null,"abstract":". Research on behalf of comfort indoor microclimate conditions in premises with different assignment is still relevant, as soon as it helps to design of buildings in a way that ensure comfortable occupancy for people and eliminate unnecessary energy excesses. Nowadays, comfort conditions are estimated with PMV, PPD and local PD indices, which, in turn, calculated from local thermal parameters such as air temperature [°C], relative humidity [%], air velocity [m/s], the temperature of solid bodies [°C] and turbulence intensity [%]. All above-mentioned local thermal parameters can only be calculated through Computational Fluid Dynamics (CFD) technology. This article provides a system of differential equations that fully govern indoor microclimate thermophysical processes (air-flow convection and solid body radiation) and explains the possibility of its simplifications for practical engineering applications. A new methodology is proposed for indoor microclimate study, which combines air flow thermophysical simulation in OpenFOAM software and experimental data for thermal radiation. For air-flow simulation, it is suggested to use buoyantPimpleFoam solver (governing differential equations system is provided), which shows good results. Experimental data should be obtained in series of laboratory test for every single heating device with following variable parameters: distance from the wall to parallel positioned heating device [m], time [s], the concentration of water vapour and dust in the air. Implementation of this methodology will reduce the likelihood of local discomfort in every single part of a room due to precise numerical computation of air-flows while ensuring an adequate calculation rate replacing differential equation for radiative heat transfer with experimental data that represents time-dependent temperature [°C] of internal enclosures.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"115 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76726937","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":"Method for Calculating Greenhouse Gas Emissions from the Operation of Engineering Systems of Buildings","authors":"Mykhailo Kordiukov, V. Mileikovskyi","doi":"10.32347/2409-2606.2020.0.34-43","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.0.34-43","url":null,"abstract":". Reducing greenhouse gas emissions is currently a priority for human civilization to reduce climate change. Engineering systems of buildings (heating, ventilation, air-conditioning, lighting, etc.) make a significant contribution to the carbon footprint. The methodology proposed in this article makes it possible to estimate the amount of emission from each of the systems and outline ways to reduce them. A feature of the proposed methodology is the following provisions. The contribution to the greenhouse gas emissions of all engineering systems that ensure the comfort of the building’s premises is considered. The comfort of the building’s premises is considered in accordance with EN 15251 “Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal en-vironment, lighting and acoustics”. The environmental parameters are determined in accordance with the author’s methodology. When developing the methodology, the following simplifications were made. The winter humidification system is not considered, while the dehumidification of air in summer during air conditioning is taken into account. Coeffi-cients of working hours of systems are given as an example. Normative indicators are considered in accordance with DSTU B A.2.2-12 “Energy efficiency of buildings. Method of calculating energy consumption for heating, cooling, ventilation, lighting and hot water supply”. The technique can be used both for estimating the CO 2 emissions of existing buildings and for choosing the option of forming the microclimate of the designed building. An especially useful technique may be to select the appropriate microclimate formation technology for building reconstruction by comparing the amount of emission from various options. Priorities of improvement of the engineering systems can be grounded based on their share in whole CO 2 emission.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"118 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77922886","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":"Secondary Air in the Scheme of Combustion of Solid Fuel in the Layer","authors":"M. Senchuk","doi":"10.32347/2409-2606.2020.0.24-33","DOIUrl":"https://doi.org/10.32347/2409-2606.2020.0.24-33","url":null,"abstract":". Various methods of stream combustion in layer furnaces are considered with the analysis of their influence on the efficiency of mixing of overlayers combustible gases with air for the formation of necessary combustion conditions to ensure the completeness of combustion of the gas-air mixture. The expediency of using in the solid fuel low power heat generators the system of air (secondary) blast with low pressure of blast air is shown. The analysis of secondary air flow circuits in classical technological schemes of solid fuel combustion in a layer (flow, direct flow, transverse) and their im-plementation in the structures of common mechanical furnace devices (with a retort, with a poke plank and with a chain grill) are presented. The paper deals with different schemes of secondary air supply in combined technological schemes of solid fuel combustion. The technical solutions for the main structural units of the secondary air systems in the furnace are presented. For the shaft type of a furnace, there are profile muzzles on the secondary air nozzles at the outlet of the fuel shaft. For the shaft-layer type of a furnace, there is a water-cooled air collector with blast nozzles in the gasification zone of the fuel. Due to the rational organization of the secondary air supply, depending on the quality of the combusted fuel (volatile yield, humidity, ash content, fractional composition), a mixture of over-gases with air is formed. The concentra-tion and temperature conditions of it should ensure its reliable ignition, stable combustion and complete combustion of combustible substances. The paper substantiates the choice of an effective air blowing system for mechanical furnaces in low-power shaft boilers (up to 4 MW). Effective burning of over-gases rises the efficiency of boilers and decreases atmo-spheric pollution.","PeriodicalId":23499,"journal":{"name":"Ventilation, Illumination and Heat Gas Supply","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86969480","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}