Wyniki wyszukiwania - BazTech

1

Mapa drogowa dla magazynów ciepła

Wiśniewski Grzegorz, Orzechowski Sebastian, Dziamski Piotr, Jaworowska Beata

Energia i Recykling : gospodarka obiegu zamkniętego

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2024

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nr 10

PL

Instytut Energetyki Odnawialnej wraz z Polską Izbą Magazynowania Energii 5 września br. opublikowały „Mapę drogową dla magazynów ciepła w Polsce”. Ten obszerny raport dotyczy kluczowej roli magazynów ciepła w stabilizacji systemu energetycznego w Polsce.

2

Employing a Combination of a Double-Glazed Flat Solar Collector and Sensible Heat Storage for Drying Agricultural Products

Efendi Mohamad, Hendrawan Yusuf, Hawa La Choviya, Argo Bambang Dwi

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 5

106--118

EN

Convection heat collector technology is a promising technology for drying agricultural products. The study aimed to determine the temperature characteristics, energy efficiency, and thermal discharging of a flat plate-type collector using double-glazing technology integrated with heat storage material in the state of iron scraps in passive and active modes. Investigation was conducted for seven hours of exposure under the sun (08:00–15:00 local time). Ten temperature sensors and four humidity sensors were used during measurements to determine the thermal characteristics of the heat collector. The density of iron scraps as heat storage material is 250 kg/m3 with an irradiation time of seven hours. The results indicate that the passive mode of operation has a higher temperature characteristics than the active mode. During irradiation process, the highest temperatures on the absorber in active and passive modes were 63 °C and 55 °C, respectively. Meanwhile, the highest temperatures on the TES in passive and active modes during irradiation were 55.6 °C and 50.6 °C, respectively. The energy efficiency of the collector ranges from 23.3–55.1% (passive) and 18.6–40.7% (active). The energy efficiency of the TES (Thermal Energy Storage) has a range of 7.4–22.7% (passive) and 7.4–13.0% (active). During discharging process, it shows that the TES in passive mode can store heat for 275 minutes and active mode for 95 minutes. Heat collectors that used double glazing technology and heat storage materials using iron scraps with a density of 250 kg/m3 have a significant potential to extend the drying duration of agricultural products with limited exposure to sunlight and environmentally friendly heat collectors.

3

Simulations and techno-economic analysis of solar cooling system

Kalina Jacek, Rabiej Michał, Santos Silva Carlos

Archives of Thermodynamics

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2024

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Vol. 45, no 2

145--155

EN

In this paper, a solar absorption cooling system with a chilled water storage tank and peak load compression system was considered for cooling the Instituto Superior Tecnico Tower building in Lisbon, Portugal. To fulfill this task, a dynamic simulation of the building was performed using the DesignBuilder software, then a solar collector field was designed. The next step was to build a computational model of the absorption chiller in the Engineering Equation Solver software, which allowed for further simulation of the annual operation of the system supported by the chilled water tank and the backup system with compressed air conditioning. The last stage of the work was the economic analysis of such a system in comparison with conventional compressed air conditioning. The simulation results and economic analysis showed that the solar absorption cooling system could be a beneficial cooling solution for the Instituto Superior Tecnico Tower building. However, it would have to operate with an energy storage system and a peak load compression backup system to be able to cool the building efficiently all year round. Additionally, such a solution could have a significant positive impact on climate through considerable annual savings in electricity consumption. Results revealed that the proposed system meets the cooling demand of the building, mainly by solar-energy-driven absorption chiller. The annual contribution of a backup compression chiller ranges from 20% to 36% depending on the size of chilled water storage tanks. Financial calculations revealed discounted payback periods in the range of 4.5 to 12.5 years depending on the system configuration.

4

Technologie instalacyjne wykorzystujące materiały zmiennofazowe

Durczak Karolina, Spik Zenon, Zawada Bernard

Ciepłownictwo, Ogrzewnictwo, Wentylacja

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2023

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T. 54, nr 7-8

38--43

PL

Celem niniejszego artykułu jest wskazanie możliwych aplikacji materiałów zmiennofazowych w zakresie instalacji sanitarnych. PCM, dzięki wykorzystaniu ciepła przemiany fazowej, pozwalających na efektywniejsze magazynowanie energii. W pracy wskazano jakie zalety ma zastosowanie takich technologii w budownictwie a także pokazano przykładowe rozwiązania, stanowiące jedynie część potencjalnych zastosowań. Na podstawie przedstawionych materiałów, można stwierdzić że użycie nowych technologii pozwala na oszczędności eksploatacyjne instalacji. Jednak nie odnosi się to kosztów inwestycyjnych, które w większości konfiguracji będą większe dla klasycznych rozwiązań instalacyjnych grzewczo-chłodzących.

EN

The purpose of this work is to indicate the possible applications of phase change materials in the field of sanitary installations. PCMs, thanks to the use of phase transfer heat, allow for more efficient energy storage. The paper shows the advantages of using such technologies in the construction industry and shows examples of solutions that are only part of the potential applications. Based on the presented materials, it can be concluded that the use of new technologies allows for operating savings of the installation. However, this does not apply to investment costs, which in most configurations will be higher for classic heating and cooling installation solutions.

5

Inorganic salt hydrates as Phase Change Materials (PCM) for thermal energy storage in solar installations

Styś-Maniara Marta, Nartowska Edyta, Metryka-Telka Monika, Porowski Rafał

Structure and Environment

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2022

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Vol. 14, no. 4

161--172

EN

The authors present a general idea of using inorganic salt hydrates in solar installations. A key role in this selection is played by thermophysical parameters, so the authors review their test methods and in turn characterize them for the most promising salt hydrates. Next, the authors describe the advantages and disadvantages of inorganic salt hydrates and indicate possibilities for their improvement. The use of salt hydrate converters in PV installations significantly improves the efficiency of photovoltaic modules. We show that at least 18 salt hydrates are promising for solar applications with the best ones being Sodium Hydrogen Phosphate Dodecahydrate, Sodium Carbonate Decahydrate and Calcium Chloride Hexahydrate. The selection of a test method for determining the thermophysical parameters of salt hydrates should be individual depending on the research objective. Comparing the methods presented, we believe that it is the DSC and DTA methods that provide the most accurate and repeatable results.

PL

Autorzy przedstawiają ogólną koncepcję wykorzystania nieorganicznych hydratów solnych w instalacjach solarnych. Kluczową rolę w tym doborze odgrywają parametry termofizyczne, dlatego autorzy dokonują przeglądu metod ich badania i kolejno charakteryzują je dla najbardziej obiecujących hydratów solnych i ich mieszanin. Następnie autorzy opisują zalety i wady nieorganicznych hydratów solnych oraz wskazują możliwości ich udoskonalenia. Zastosowanie konwerterów hydratów solnych w instalacjach PV znacząco poprawia sprawność modułów fotowoltaicznych. Wykazano, że co najmniej 18 hydratów soli i ich mieszanin jest obiecujących dla zastosowań solarnych ze względu na korzystne parametry termofizyczne, przy czym najlepsze z nich to dodekahydrat wodorofosforan sodu, dekahydrat węglanu sodu i heksadydrat chlorku wapnia. Z przeglądu literatury wynika, że wybór metody badawczej do określenia parametrów termofizycznych hydratów soli powinien być indywidualny w zależności od celu badań. Porównując przedstawione metody, stwierdzono, że to właśnie metody DSC i DTA dają najbardziej dokładne i powtarzalne wyniki.

6

Identyfikacja właściwości termicznych materiałów fazowo zmiennych z dodatkiem wybranych nanomateriałów

Wołoszyn Jerzy

Przemysł Chemiczny

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2022

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T. 101, nr 11

1023--1026

PL

Główną wadą organicznych materiałów fazowo zmiennych, które są coraz częściej stosowane w magazynach energii termicznej, jest ich niska przewodność cieplna. Zmniejszenie oporu cieplnego po stronie medium magazynującego realizowane poprzez dodanie nanomateriałów to jeden ze sposobów na poprawę efektywności procesu wymiany ciepła. Przeprowadzono badania entalpii i temperatury przemiany fazowej, ciepła właściwego oraz czasu przemiany fazowej w trakcie topnienia i krzepnięcia komercyjnie dostępnego materiału fazowo zmiennego z dodatkiem dwóch rodzajów nanoproszków (a-Fe₂O₃ i a-Al₂O₃) o udziale masowym 0,8%, 6,5% oraz 13%. Nie stwierdzono znacznego obniżenia entalpii i temperatury przemiany fazowej dla każdej z przygotowanych próbek. Istotnym negatywnym efektem towarzyszącym przy wzroście udziału nanomateriału był znaczny wzrost czasu przemiany fazowej w trakcie topnienia.

EN

The enthalpy and phase transition temp., sp. heat and phase transition time were detd. during melting and solidification of com. available phase transition material and with the addn. of 2 types of nanopowders (a-Fe₂O₃, a-Al₂O₃) in the amt. of 0.8%, 6.5 % or 13%. No significant decrease in enthalpy and phase transition temp. was observed for each of the prepared samples. A significant neg. effect accompanying the increase in nanomaterial content was a significant extension of the phase transition time during melting.

7

Experimental studies of packed-bed Thermal Energy Storage system performance

Ochmann Jakub, Bartela Łukasz, Rusin Krzysztof, Jurczyk Michał, Stanek Bartosz, Rulik Sebastian, Waniczek Sebastian

Journal of Power Technologies

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2022

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Vol. 102, nr 1

37--44

EN

This paper contains an experimental analysis of a heat storage tank's heat loss and exergy efficiency using a basalt porous bed as a storage material. The basic parameters of the laboratory bench with measuring equipment are presented and the experimental procedure is discussed. The methodology for evaluating the energy potential of the heat storage process for large-scale energy storage systems is described. The main novelty of the presented system is the application of the slenderness of the heat accumulator, which corresponds to the development of the system in a post-mining shaft. Based on the analysis of the experiment, the exergy cycle efficiency of the heat storage unit was determined to equal 52.3%, and the energy efficiency equal to 96.6%.

8

Mobile thermal energy storage (M-TES)

Demchenko Volodimir, Konyk Alina

Journal of New Technologies in Environmental Science

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2022

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Vol. 6, nr 3

91--96

EN

The main world trends aimed at creating new energy systems, highly efficient and, at the same time, with a careful attitude to the surrounding environment, intensified the creation and protection of energy storage systems. One of the areas that is actively developing is mobile heat accumulators that work on this technology of latent heat storage. The article presents a new design of a mobile heat accumulator with a short-term heat storage period. A combination of several types of coolants is used as an accumulation system. The technical and technological characteristics of M-TES-0.5 MW are given. The most promising mobile thermal energy storage devices, which implement a similar principle of thermal energy conservation and have a positive experience of use, were noted.

9

Physical Characteristics of Aceh Traditional Salt and Its Potential as Raw Material for Thermal Energy Storage

Gunawati, Humaidi Syahrul, Setiawan Adi, Sirait Makmur, Jalil Zulkarnain, Ramadhani Nadilla, Makruf Amar, Riskina Shafira, Irhamni

Journal of Ecological Engineering

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2022

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Vol. 23, nr 2

116--122

EN

Thermal energy storage is an important element in order to conserve the energy and optimize the overall efficiency. Development of energy storage system for local purposes requires some information on the raw material which is abundantly available in the local market. This study aimed to investigate the characteristics of traditionally produced salt in Aceh in terms of its potential use as a raw material for thermal energy storage. The sample was collected from the Aceh Besar District and treated by heating at temperatures of 400 °C and 800 °C in a muffle furnace. This treatment is carried out to study the changes in properties and define the best procedure for salt preparation. All samples were characterized under a number of techniques including XRF, XRD, SEM/EDS, TGA/DSC analysis, density, thermal conductivity, and electrolytic conductivity. The XRF characterization showed that the local Aceh salt was graded as a category III salt. Furthermore, according to the TGA/DSC characterization, the melting temperature is close to 800 °C, and the enthalpy value is close to 492 kJ/kg. It is ample evidence that the Aceh salt can be used as a thermal energy storage material. Furthermore, increasing the temperature of local salt’s heat treatment contributes to increasing the enthalpy value, crystal size, density, thermal conductivity, and electrolyte conductivity.

10

Model efektywnego systemu ciepłowniczego na bazie energii solarnej

Mirek Justyna, Słomczyńska Klaudia, Mirek Paweł

Instal

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2022

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nr 11

19--27

PL

Odchodzenie od spalania paliw węglowych, zwiększenie wykorzystania odnawialnych źródeł energii, a w konsekwencji uzyskanie statusu efektywnego systemu ciepłowniczego - to podstawowe priorytety oraz wyzwania związane z produkcją ciepła systemowego w Polsce. Jednym ze sposobów osiągnięcia przez system ciepłowniczego statusu efektywnego, jest zwiększenie udziału pogodowozależnych odnawialnych źródeł energii. Wykorzystanie tego typu źródeł wpływa dodatkowo na poprawę bezpieczeństwa energetycznego poprzez uniezależnienie od dostaw paliw z zewnętrz oraz stabilizację cen ciepła. W pracy przedstawiono koncepcję systemu ciepłowniczego wykorzystującego energię promieniowania słonecznego, opartego o wielkoformatowe farmy solarne połączone z sezonowym magazynem ciepła oraz farmy fotowoltaiczne, w którym odnawialne źródła energii stanowiły ponad 93% całkowitej energii wprowadzonej do układu. Dodatkowo porównano dwa warianty systemu - różniące się od siebie zastosowaniem instalacji elektrolizy wodoru oraz jednostki kogeneracyjnej z wykorzystaniem silników wodorowych. Obliczenia przeprowadzano w polskich warunkach pogodowych, z wykorzystaniem oprogramowania symulacyjnego TRNSYS 18. Wykazano, że zastosowanie silnika kogeneracyjnego podnosi jednostkowy koszt ciepła o 16,75 zł/GJ bez wyraźnego wpływu na zwiększenie udziału OZE w procesie produkcji energii oraz efektywność energetyczną. W przypadku badanej wielkości instalacji bardziej uzasadniona ekonomicznie jest koncepcja systemu bez ścieżki wodorowej (LCOH = 99,43 zł/GJ).

EN

Moving away from burning coal-based fuels, increasing the use of renewable energy sources, and consequently achieving efficient district heating system status - these are the main priorities and challenges for system heat production in Poland. One way for a district heating system to achieve efficient status is to increase the share of weather-dependent renewable energy sources. The use of such sources additionally improves energy security through independence from external fuel supplies, and stabilizes heat prices. The paper presents a concept of a solar thermal system, based on large-scale solar farms combined with seasonal heat storage, and photovoltaic farms, in which renewable energy sources accounted for more than 93% of the total energy input into the system. In addition, two variants of the system were compared - differing in the use of a hydrogen electrolysis plant, and a cogeneration unit using hydrogen engines. Calculations were carried out under Polish weather conditions, using the TRNSYS 18 simulation software. It was shown that the use of a cogeneration engine raises the unit cost of heat by 16.75 PLN/GJ without a clear impact on increasing the share of RES in the energy production process, and energy efficiency. For the size of the plant under study, the system concept without the hydrogen path (LCOH = PLN 99.43/GJ) is more economically justified.

11

Thermal energy storage in buildings: Opportunities and challenges

Deka Priyam, Szlęk Andrzej

Archives of Thermodynamics

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2022

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Vol. 43, no 4

21--61

EN

The energy sector is a majorarea that is responsible for the country development. Almost 40% of the total energy requirement of an EU country is consumed by the building sector and 60% of which is only used for heating and cooling requirements. This is a prime concern as fossil fuel stocks are depleting and global warming is rising. This is where thermal energy storage can play a major role and reduce the dependence on the use of fossil fuels for energy requirements (heating and cooling) of the building sector. Thermal energy storage refers to the technology which is related to the transfer and storage of heat energy predominantly from solar radiation, alternatively to the transfer and storage of cold from the environment to maintain a comfortable temperature for the inhabitants in the buildings by providing cold in the summer and heat in the winter. This work is an extensive study on the use of thermal energy storage in buildings. It discusses different methods of implementing thermal energy storage into buildings, specifically the use of phase change materials, and also highlights the challenges and opportunities related to implementing this technology. Moreover, this work explains the principles of different types and methods involved in thermal energy storage.

12

Performance analysis and PCM selection for adsorption chiller aided by energy storage supplied from the district heating system

Karwacki Jarosław, Kwidziński Roman, Leputa Piotr

Archives of Thermodynamics

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2022

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Vol. 43, no 4

135--169

EN

The paper presents a theoretical analysis of thermal energy storage filled with phase change material (PCM) that is aimed at optimization of an adsorption chiller performance in an air-conditioning system. The equations describing a lumped parameter model were used to analyze internal heat transfer in the cooling installation. Those equations result from the energy balances of the chiller, PCM thermal storage unit and heat load. The influence of the control of the heat transfer fluid flow rate and heat capacity of the system components on the whole system operation was investigated. The model was used to validate the selection of Rubitherm RT62HC as a PCM for thermal storage. It also allowed us to assess the temperature levels that are likely to appear during the operation of the system before it will be constructed.

13

Hybrid nano improved phase change material for latent thermal energy storage system: Numerical study

Benlekkam Mohamed Lamine, Nehari Driss

Archive of Mechanical Engineering

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2022

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LXIX, nr 1

77--98

EN

The phase change materials (PCM) are widely used in several applications, especiallyi n the latent heat thermal energy storage system (LHTESS). Due to the very low thermal conductivity of PCMs. A small mass fraction of hybrid nanoparticles TiO 2–CuO (50%–50%) is dispersed in PCM with five mass concentrations of 0%, 0.25%, 0.5%, 0.75% and 1 mass % to improve its thermal conductivity. This article is focused on thermal performance of the hybrid nano-PCM (HNPCM) used for the LHTESS. A numerical model based on the enthalpy-porosity technique is developed to solve the Navier-Stocks and energy equations. The computations were conducted for the melting and solidification processes of the HNPCM in a shell and tube latent heat storage (LHS). The developed numerical model was validated successfully with experimental data from the literature. The results showed that the dispersed hybrid nanoparticles improved the effective thermal conductivity and density of the HNPCM. Accordingly, when the mass fraction of a HNPCM increases by 0.25%, 0.5%, 0.75% and 1 mass %, the average charging time improves by 12.04 %, 19.9 %, 23.55%, and 27.33 %, respectively. Besides, the stored energy is reduced by 0.83%, 1.67%, 2.83% and 3.88%, respectively. Moreover, the discharging time was shortened by 18.47%, 26.91%, 27.71%, and 30.52%, respectively.

14

Role of thermal energy storage technology in the decarbonization of energy sector process - packed rock bed parameters analysis

Ochmann Jakub, Jurczyk Michał, Bartela Łukasz

Architecture Civil Engineering Environment

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2022

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Vol. 15, no. 3

65--74

EN

The paper presents the adiabatic installation of compressed gases energy storage. The authors present the results of analyzes for this type of installation due to the selection of thermal storage material. The simulations were carried out for basalt, granite and ceramics (alumina) as well as for porosity value from 0.375 to 0.39 of basalt-filled reservoirs in Thermal Energy Storage (TES) installation. Characteristics of outlet air temperature, air pressure drop amount of energy stored and external heat losses as a time functions during the charging phase are presented. The research indicated that due to the lowest density and average heat capacity of the materials studied, granite has the fastest and most intense physical exit loss from the storage tank which was approximately 1100 W. However, there was no significant effect on air pressure drop depending on the chosen accumulation materials. The effect of rock bed porosity on the pressure drop of flowing air was investigated. For a constant mass flow rate, pressure drop values ranging from 2200 Pa to 6200 Pa were obtained depending on the porosity value.

15

Integration of Heat Storage Technologies in District Heating Systems

Konyk Alina, Demchenko Vladimir

Rocznik Ochrona Środowiska

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2021

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Tom 23

493--502

EN

Global trends in the efficiency, safety of energy systems and energy conservation actualize the task of developing new technologies for energy storage and transportation. The article considers current technologies of storage and accumulation of thermal energy, which can be used in central heating systems, and draws conclusions about the feasibility of their use. Also, the classification of energy storage systems is presented. The most perspective thermal energy storage, which can be used to equalize the load on the energy source to ensure the peak demand for heat with a high coefficient of utilization of the equipment capacity, is noted.

16

Charakterystyka materiałów zmiennofazowych

Durczak Karolina, Zawada Bernard, Spik Zenon

Rynek Instalacyjny

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2020

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Nr 12

30--34

PL

Celem niniejszej pracy było wskazanie podstawowych parametrów, jakimi powinny się charakteryzować materiały zmiennofazowe (PCM) wykorzystywane w technice instalacyjno-budowlanej. W artykule podano charakterystyczne parametry cieplne różnych związków chemicznych pełniących funkcję PCM. Dobranie materiału o właściwościach dopasowanych do celu, np. magazynowania nadwyżek ciepła występujących w pomieszczeniu, pozwala na uzyskanie wymiernych korzyści energetycznych. Dodatkowo w artykule wskazano możliwe sposoby wkomponowania materiału zmiennofazowego w komponenty budowlane. Spośród dostępnych technologii to mikrokapsulacja umożliwia wyeliminowanie w największym stopniu podstawowych problemów związanych ze specyfiką działania PCM, tj. wycieki, zmiany objętości związane ze zmianą fazy czy niestabilność konstrukcji.

EN

The aim of this study was to indicate the basic parameters that should characterized the phase change materials (PCM) used in installation and construction technology. The paper presents characteristic thermal parameters of various chemical compounds that play the role of PCM. The selection of materials with properties tailored to the purpose, e.g. storing excess heat in the room, allows for measurable energy benefits. Additionally, the material indicates possible ways of integrating the phase change material into building components. Among the available technologies, microcapsulation is the best solution to eliminate the basic problems related to the specificity of PCM operation, i.e. leakages, volume changes related to phase change, structure stability.

17

Thermal energy storage in rock bed - CFD analysis

Jurczyk Michał, Rulik Sebastian, Bartela Łukasz

Journal of Power Technologies

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2020

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Vol. 100, nr 4

301--307

EN

This article reports on an analysis of the possibility of storing thermal energy in a rock bed. The calculations were made in Ansys CFX 18.0 CFD. The analysis determined the charging time of a packed bed of granite rocks in variable flow conditions for the assumed geometry of the energy storage system. The model was 2-dimensional, consisting of two domains connected by an interface. The packed bed was modelled using a porous model approach. The inlet velocity was varied in the range 0.25-4 m/s. The total charging time was 70 to 1100 min, depending on inlet velocity.

18

Możliwości zmniejszenia energochłonności budynków dzięki wykorzystaniu materiałów zmiennofazowych

Durczak Karolina, Zawada Bernard, Spik Zenon

Rynek Instalacyjny

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2019

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Nr 7-8

42--46

PL

Celem niniejszej pracy było wykazanie korzyści płynących z zastosowania materiałów zmiennofazowych do zmniejszenia energochłonności budynków dzięki możliwości akumulacji ciepła i wykorzystywania go w momencie, gdy jest ono potrzebne. Metody wykorzystujące materiały PCM swoje działanie opierają na zmianie fazy materiału, czemu towarzyszy pochłanianie oraz oddawanie energii. Bodźcem do zmiany fazy, a tym samym do akumulowania lub oddawania ciepła, jest zmiana temperatury otoczenia. W artykule zawarto charakterystykę ogólną materiałów PCM, opisano materiały wykorzystywane w budownictwie oraz dostępne techniki korzystające z materiałów zmiennofazowych w celu poprawy warunków termicznych panujących w budynku, a także wspomagające instalacje wodne (głównie ciepłej wody użytkowej). Na podstawie przeprowadzonej analizy można stwierdzić, że zastosowanie elementów budowlanych z PCM jest korzystne i w znaczny sposób przyczynia się do obniżenia kosztów utrzymania wymaganej temperatury w pomieszczeniu. Przy stosowaniu tego typu rozwiązań należy jednak pamiętać o wadach materiałów zmiennofazowych, szczególnie braku stałości ich właściwości w powtarzalnych cyklach oraz problemach z precyzyjnym określeniem momentu zmiany fazy, które mogą zmniejszyć rzeczywiste korzyści.

EN

The aim of this work was to demonstrate the benefits of using phase change materials to reduce energy consumption of buildings by the possibility of heat accumulation and using it when it is needed. Methods using PCM materials are based on the change of the material phase which is accompanied by absorption and energy donation. The stimulus to change the phase, and thus to accumulate or give off heat, is to change the ambient temperature. The work presents general characteristics of PCM materials, describes materials used in construction and available techniques using phase change materials to improve thermal conditions prevailing in the building and supporting water installations (mainly hot water). Based on the analysis, it can be concluded that the use of building components with PCM is beneficial and significantly contributes to reducing the cost of maintaining the required room temperature. However, when using this type of solution, one should remember about the disadvantages of phase-change materials, mainly in relation to the lack of constancy of material properties in repeatable cycles and problems in precisely determining the moment of phase change, which can reduce the real benefits.

19

Implementation of heat storage and network water cooler for improvement of energy and economic performance of municipal heating plant with biomass fired cogeneration module

Świerzewski Mateusz, Kalina Jacek

Journal of Power Technologies

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2019

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Vol. 99, nr 2

131--141

EN

Many fossil fuel fired municipal heating plants have been upgraded to cogeneration systems through installation of biomass fired cogeneration modules. This paper shows the effects of installing an Organic Rankine Cycle (ORC) technology based module in a plant with coal fired water boilers. Current problems related to operation of the integrated system are presented and discussed. Special attention is given to the volatility of the main operational parameters, which impacts the economic performance of the project. With a view to enhancing performance, new equipment such as heat storage and a district heating water cooler are proposed and examined. A mathematical simulation model and optimization algorithm for thermal energy storage capacity sizing were developed using the commercial software EBSILON® Professional. The model was calibrated and validated with real measurement data from the SCADA system of the plant. Results of simulations revealed potential annual financial benefits related to savings of chemical energy of fuels and selling excess electricity on the balancing market. The results of these simulations prove that proposed modifications of the technological system structure could be a good option for increasing investment profitability at the current level of fuel and energy prices.

20

Analysis of thermal parameters of heat storages for use in vehicles with combustion engines

Mężyk Przemysław, Przybyła Grzegorz, Petela Karolina

Combustion Engines

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2019

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R. 58, nr 4

119--125

EN

The propulsion system of a vehicle using an internal combustion engine generates a significant amount of waste heat during operation, which is almost entirely discharged into the environment without any useful effect. One of the ways of using waste heat is storing it, and then using, for example, when starting the engine in winter conditions. The application of the indicated solution, in particular for the combat vehicle will allow to reduce the effects of cold start and will shorten the time of preparing such a vehicle for combat operations. The article presents: types of heat accumulators that could be used in a military vehicle, the results of preliminary tests carried out on the test stand and the impact of an additional heat source on the time of heating the internal combustion engine and on emission of exhaust gas components.