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Division of Heating, Ventilation, Air Conditioning and Refrigeration
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Catalog Publications
Year 2024
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A New Approach of Solidification Analysis in Modular Latent Thermal Energy Storage Unit Based on Image Processing
PublicationThe solidification process of RT18HC in a cylindrical shell and tube storage unit has been studied using a new methodology based on image processing. The main idea of the algorithm is to label the region of solidification and use statistical functions to calculate the dimensions of the solidification front over time. Said analysis includes two methods. The first method is to measure the solid fraction changes during solidification....
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Assessment of thermal and electrical performance of flat plate air-cooled photovoltaic roof tile – experimental and numerical studies
PublicationThe current state of development of the solar energy sector necessitates a new form of incentive for entities to invest in photovoltaic (PV) installations. Building-integrated photovoltaic/thermal (BIPV/T) systems are gaining increasing interest. Effective methods for heat recovery from BIPV/T collectors are searched for. Presented research experimentally and numerically considered the influence of cooling conditions on the electrical...
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Experimental and numerical study of thermal and electrical potential of BIPV/T collector in the form of air-cooled photovoltaic roof tile
PublicationAmong renewable energy sources, Building-Integrated Photovoltaic/Thermal (BIPV/T) systems are gaining increasing interest. To improve their economic competitiveness, technologies that increase their efficiency are searched for. The paper is devoted to evaluating the impact of various air-cooling configurations on the thermal and electrical performance of a photovoltaic roof tile. A numerical model of the own experimental system...
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Window frame integrable air recuperation minichannel/minigap heat exchanger
PublicationThis article describes an evaluation of mini heat exchangers operation as a decentralized mechanical ventilation system with recuperative heat recovery that can be integrated into the window frame. The relatively small yet efficient air recuperation system allows for retrofitting existing buildings by reducing the overall energy consumption and thus the CO2 emissions. The proposed design, unlike existing systems, is easy to scale...
Year 2023
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A review of phase change materials and heat enhancement methodologies
PublicationPhase change materials (PCMs) are an efficient alternative to store and release heat at a specific range of temperature. Here PCMs and heat enhancement methodologies for PCM storage are reviewed. A short overview of PCMs and their applications is presented in addition to the progress during the last 10 years. Heat enhancement techniques, that is, extended surfaces, multiple and composite PCMs, and encapsulation techniques, are...
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Analiza eksperymentalna intensyfikacji transportu ciepła w płaszczowo-rurowym wymienniku ciepła z generatorami strug gazu
PublicationW pracy przedstawiono modelowy płaszczowo-rurowy wymiennik ciepła z generatorami strug gazu wraz z wynikami badań cieplnych. Badania eksperymentalne wykonano dla układu gaz-ciecz. Pomiary prowadzono przy stałych wartościach temperatury czynników na wlocie do wymiennika, tj. w zakresie 120-200 st.C w przypadku powietrza (czynnika grzewczego) i 18 st.C w przypadku wody (czynnika ogrzewanego). Przedstawiono zależności współczynnika...
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Experimental and numerical investigation on shell and coil storage unit with biodegradable PCM for modular thermal battery applications
PublicationThermal energy storage (TES) in automotive applications is currently growing in importance. TES can visibly reduce primary energy consumptions, decrease CO2 emission, and improve thermal comfort in electric as well as hybrid vehicles. However, to meet the new ambitious target (15% reduction of CO2 emissions in the new cars until 2025) it is required to use plug-in electric vehicles. For this reason, this paper focuses on the optimization...
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Heat transfer enhancement of modular thermal energy storage unit for reversible heat pump cooperation
PublicationThe following article presents experimental comparison research on a hexagonal shelland-tube latent thermal energy storage (TES). Such shape of a shell was deliberately chosen instead of a cylindrical one due to its high modularity and with intent for future applications in automobiles (EV and PHEV) air conditioning systems (HVAC). Two geometries of helical coils, acting as tubes, were studied in this article. One was a simple...
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Modeling of low calorific gas burning in a deficient oxygen environment and high-temperature oxidizer
PublicationThe experimental research will be performed using the experimental facility with a combustion chamber. The oxygen concentration in combustion oxidizers will be varied from 21% by volume (normal) air to 2%. The test combustion chamber will be fed with propane or methane as the reference fuel, then with low calorific fuels as test gases obtained by mixing various combustible components, e.g. H2, CH4, CO, and neutral gases, e.g. N2,...
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Ocena wpływu zastosowania techniki strugowej na wydajność energetyczną modułów BIPV/T chłodzonych powietrzem
PublicationPraca ma charakter analizy numerycznej i dotyczy problematyki chłodzenia hybrydowych modułów fotowoltaicznych dedykowanych układom Building-Integrated Photovlotaic/Thermal (BIPV/T). Uwagę skupiono na powietrznym systemie chłodzenia dachówki fotowoltaicznej, rozważając technikę strugową, w której intensyfikację wymiany ciepła zapewniają strugi płynu uderzające w przegrodę wymiany ciepła. Przeprowadzono szereg symulacji numerycznych...
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Optimisation of cooperation of hybrid renewable energy sources with hydrogen energy storage toward the lowest net present cost
PublicationThe paper presents the results of a technical and economic analysis of the power supply for a model industrial facility based on intermittent renewable energy sources in the form of wind turbines and photovoltaic modules, supplemented with hydrogen energy storage. The adopted power supply strategy assumed the maximisation of self-consumption of self-produced electricity. Six variants were considered, including two with an energy...
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Recent advances of selected passive heat transfer intensification methods for phase change material-based latent heat energy storage units: A review
PublicationThe following article overviews recent studies regarding heat transfer enhancement methods, explicitly focusing on fins and coils utilization, in phase change material-based latent heat thermal energy storage systems. It discusses the influence of various geometrical and material parameters on the melting and solidification processes, as well as the orientation of the heat transfer surface within the storage tank. Additionally,...
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Recycling of photovoltaic modules - legal status, technology, market prospects
PublicationThe increase in the number of manufactured and installed photovoltaic modules and the growing concern about the insufficient supply of pure silicon imply the need to take action to develop infrastructure for recycling PV modules. The article presents a multifaceted analysis of the current state of development of the photovoltaic module recycling sector from a global and national perspective. The essence of the issue was introduced...
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Study on effective front region thickness of PCM in thermal energy storage using a novel semi-theoretical model
PublicationThermal energy storage in mobile applications, particularly battery of electric vehicles, is currently gaining a lot of importance. In this paper, a semi-theoretical time-dependent mathematical model of the phase change in a double shell thermal energy storage module has been developed where the inner tube is a heat exchange surface. An effective front region thickness for the melting and solidification process has been studied....
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Techno-economic assessment of cooperation of hybrid renewable energy sources with hydrogen storage
PublicationThe paper presents a technical and economic analysis of the power supply for a model industrial facility with the use of the most promising renewable energy sources (RES), supported by a hydrogen energy storage. This scenario was compared with the variants of supplying the facility directly from the grid and from RES without energy storage. A strategy was proposed for powering the plant aimed at maximising self-consumption of self-generated...
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The In-House Method of Manufacturing a Low-Cost Heat Pipe with Specified Thermophysical Properties and Geometry
PublicationVarious types of heat pipes are available to purchase off the shelf, from various manufacturers, but most of them have strictly defined geometry and technical parameters. However, when there is a need to use a heat pipe (HP) with an unusual size and shape or working conditions other than the standard ones, it becomes very costly to order them from manufacturers, especially in small quantities, and only a few producers are willing...
Year 2022
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Combined cold supply system for ship application based on low GWP refrigerants - Thermo-economic and ecological analyses
PublicationThe withdrawal of popular high-GWP refrigerants will significantly affect maritime industry. Refrigeration and air conditioning systems currently used on ships are not ready to fulfil future limitations. Therefore, there is a need for system, which will operate with low-GWP refrigerants and at the same time will be efficient and reliable in difficult environmental conditions. This paper explains the concept of a cold supply system,...
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Multiple jets impingement – numerical analysis by the ζ-f and hybrid VLES turbulence models
PublicationPresented paper summarizes the Authors findings referring to the numerical analyses of the jet impinging phenomena in the case of complex jets configurations in various applications e.g. in the heat exchangers. Multiple jets interference resulting in the cross-flow and the surface curvature are the factors which impose the need of advanced turbulence models utilization. The outcome of the research based on the ζ-f turbulence model...
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Przegląd metod wytwarzania energii elektrycznej z wodoru i ocena potencjału ich zastosowania w krajowym systemie elektroenergetycznym
PublicationW artykule dokonano przeglądu dostępnych metod wytwarzania energii elektrycznej z udziałem technologii wodorowych i podjęto próbę oceny potencjału ich zastosowania w polskim systemie elektroenergetycznym. Szczególną uwagę poświęcono ogniwom paliwowym, omawiając dostępne na rynku typy ogniw oraz ich podstawowe parametry techniczne. W zakresie technologii wodorowych, rozważono możliwość samodzielnej pracy ogniw paliwowych, turbin...
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Zmiennofazowy akumulator ciepła w dolnym źródle pompy ciepła – propozycja dla budynku jednorodzinnego
PublicationW artykule przedstawiono autorskie rozwiązanie zmiennofazowego akumulatora ciepła, w którym jawne i utajone ciepło szarych ścieków jest odbierane za pomocą prototypowego wymiennika ciepła posadowionego w akumulatorze i sprzęgniętego z parownikiem pompy ciepła. Ścieki szare dopływają do akumulatora z budynku jednorodzinnego. Układ funkcjonuje w systemie grzewczym tego budynku. Omówiono doświadczenia z dotychczasowej eksploatacji...