Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Exergy analysis" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-12 z 12
    Tytuł:
    Exergetic sustainability indicators of a polymer electrolyte membrane fuel cell at variable operating conditions
    Autorzy:
    Xu, Bing
    Chen, Yan
    Ma, Zheshu
    Powiązania:
    https://bibliotekanauki.pl/articles/1845491.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    PEM fuel cell
    exergy balance
    exergy analysis
    exergetic sustainability indicators
    Opis:
    Based on the exergetic sustainability indicators of polymer electrolyte membrane (PEM) fuel cell, this paper studied the effects of irreversibility of thermodynamics on some exergetic sustainability indicators of PEM fuel cell under changing operating temperature, operating pressure and current density. Some conclusions are drawn by analyzing the curves. As the operating temperature increases, the negative impact of PEM fuel cell on various parameters due to irreversibility decreases; As the operating pressure increases, the negative impact of PEM fuel cell on various parameters due to irreversibility decreases; On the other hand, with the increase of current density, the negative impact of the PEM fuel cell on various parameters due to irreversibility increases.
    Źródło:
    Archives of Thermodynamics; 2021, 42, 1; 183-204
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An experimental study of solar air heater using arc shaped wire rib roughness based on energy and exergy analysis
    Autorzy:
    Ghritlahre, Harish Kumar
    Powiązania:
    https://bibliotekanauki.pl/articles/1955008.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    artificial roughness
    energy analysis
    exergy analysis
    solar air heater
    Opis:
    In the present study, energy and exergy analysis has been evaluated for roughened solar air heater (SAH) using arc shaped wire ribs. To achieve this aim, two different types of flow arrangement have been considered. These arrangements are: apex upstream flow and apex downstream flo. In addition to this, a smooth duct SAH has been used for comparative study. The experiments were performed using the mass flow rate of 0.007– 0.022 kg/s on outdoor condition at Jamshedpur city of India. The absorber plate roughness geometry has been designed with relative roughness height 0.0395, rib size 2.5 mm, relative roughness pitch 10 and arc angle 60◦ . The energetic and exergetic performances have been examined on the basis of the first and second law of thermodynamics. According to the results, there is observed to be the maximum thermal efficiency and exergy efficiency as 73.2% and 2.64%, respectively, for apex upstream flow SAH at 0.022 kg/s, while, at same mass flow rate the maximum thermal efficiency and exergy efficiency is obtained as 69.4% and 1.89%, respectively, for apex downstream flow SAH. In addition to this, results reported that the maximum outlet temperature and temperature difference observed at lower mass flow rate. Also examined the outlet air temperature of SAH with various mass flow rates is very important for both analysis.
    Źródło:
    Archives of Thermodynamics; 2021, 42, 3; 115-139
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Performance of a combined cycle power plant due to auxiliary heating from the combustion chamber of the gas turbine topping cycle
    Autorzy:
    Khan, Mohammad Nadeem
    Powiązania:
    https://bibliotekanauki.pl/articles/1845501.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    pressure ratio
    air-fuel ratio
    supplement heating
    exergy analysis
    energy analysis
    Opis:
    Energy demand is increasing exponentially in the last decade. To meet such demand there is an urgent need to enhance the power generation capacity of the electrical power generation system worldwide. A combined-cycle gas turbines power plant is an alternative to replace the existing steam/gas electric power plants. The present study is an attempt to investigate the effect of different parameters to optimize the performance of the combined cycle power plant. The input physical parameters such as pressure ratio, air fuel ratio and a fraction of combustible product to heat recovery heat exchanger via gas turbine were varied to determine the work output, thermal efficiency, and exergy destruction. The result of the present study shows that for maximum work output, thermal efficiency as well as total exergy destruction, extraction of combustible gases from the passage of the combustion chamber and gas turbine for heat recovery steam generator is not favorable. Work output and thermal efficiency increase with an increase in pressure ratio and decrease in air fuel ratio but for minimum total exergy destruction, the pressure ratio should be minimum and air fuel ratio should be maximum.
    Źródło:
    Archives of Thermodynamics; 2021, 42, 1; 147-162
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A comprehensive review on energy and exergy analysis of solar air heaters
    Autorzy:
    Ghritlahre, Harish Kumar
    Sahu, Piyush Kumar
    Powiązania:
    https://bibliotekanauki.pl/articles/240351.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    solar energy
    energy
    exergy analysis
    solar air heater
    thermal performance
    Opis:
    For economic growth of nation, the energy plays an important role. The excessive use of fossil fuels results the increase in global warming and depleting the resources. Due to this reason, the renewable energy sources are creating more attraction for researchers. In renewable energy sector, solar energy is the most abundant and clean source of energy. In solar thermal systems, solar air heater (SAH) is the main system which is used for heating of air. As it is simple in construction and cheaper in cost, it is of main interest for the researchers. The concept of first law and second law of thermodynamics is used for the study of the energy and exergy analysis respectively. The energy analysis is of great importance for the study of process effectiveness while the exergetic analysis is another significant concept to examine the actual behavior of process involving various energy losses and internal irreversibility. For efficient utilization of solar energy, the exergy analysis is very important tool for optimal design of solar air heaters. The aim of the present work is to review the works related to energy and exergy analysis of various types of solar air heaters and to find out the research gap for future work.
    Źródło:
    Archives of Thermodynamics; 2020, 41, 3; 183-222
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Exergy analysis of the Szewalski cycle with a waste heat recovery system
    Autorzy:
    Kowalczyk, T.
    Ziółkowski, P.
    Badur, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/240278.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Szewalski cycle
    binary vapour cycle
    exergy analysis
    waste heat
    idea Szewalskiego
    analiza egzergii
    ciepło odpadowe
    Opis:
    The conversion of a waste heat energy to electricity is now becoming one of the key points to improve the energy efficiency in a process engineering. However, large losses of a low-temperature thermal energy are also present in power engineering. One of such sources of waste heat in power plants are exhaust gases at the outlet of boilers. Through usage of a waste heat regeneration system it is possible to attain a heat rate of approximately 200 MWth, under about 90°C, for a supercritical power block of 900 MWel fuelled by a lignite. In the article, we propose to use the waste heat to improve thermal efficiency of the Szewalski binary vapour cycle. The Szewalski binary vapour cycle provides steam as the working fluid in a high temperature part of the cycle, while another fluid – organic working fluid – as the working substance substituting conventional steam over the temperature range represented by the low pressure steam expansion. In order to define in detail the efficiency of energy conversion at various stages of the proposed cycle the exergy analysis was performed. The steam cycle for reference conditions, the Szewalski binary vapour cycle as well as the Szewalski hierarchic vapour cycle cooperating with a system of waste heat recovery have been comprised.
    Źródło:
    Archives of Thermodynamics; 2015, 36, 3; 25-48
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Exergy analysis of the performance of low-temperature district heating system with geothermal heat pump
    Autorzy:
    Sekret, R.
    Nitkiewicz, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/240813.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    exergy analysis
    low-temperature geothermal water
    district heating system
    analiza egzergii
    niskotemperaturowa woda geotermalna
    ciepłownictwo systemowe
    Opis:
    Exergy analysis of low temperature geothermal heat plant with compressor and absorption heat pump was carried out. In these two concepts heat pumps are using geothermal water at 19.5°C with spontaneous outflow 24 m3/h as a heat source. The research compares exergy efficiency and exergy destruction of considered systems and its components as well. For the purpose of analysis, the heating system was divided into five components: geothermal heat exchanger, heat pump, heat distribution, heat exchanger and electricity production and transportation. For considered systems the primary exergy consumption from renewable and non-renewable sources was estimated. The analysis was carried out for heat network temperature at 50/40°C, and the quality regulation was assumed. The results of exergy analysis of the system with electrical and absorption heat pump show that exergy destruction during the whole heating season is lower for the system with electrical heat pump. The exergy efficiencies of total system are 12.8% and 11.2% for the system with electrical heat pump and absorption heat pump, respectively.
    Źródło:
    Archives of Thermodynamics; 2014, 35, 1; 77-86
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Exergy analysis of internal regeneration in supercritical cycles of ORC power plant
    Autorzy:
    Borsukiewicz-Gozdur, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/239987.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analiza egzergii
    nadkrytyczny blok węglowy
    ORC
    regeneracja ciepła
    exergy analysis
    internal heat regeneration
    supercritical power plant
    Opis:
    In the paper presented is an idea of organic Rankine cycle (ORC) operating with supercritical parameters and so called dry fluids. Discussed is one of the methods of improving the effectiveness of operation of supercritical cycle by application of internal regeneration of heat through the use of additional heat exchanger. The main objective of internal regenerator is to recover heat from the vapour leaving the turbine and its transfer to the liquid phase of working fluid after the circulation pump. In effect of application of the regenerative heat exchanger it is possible to obtain improved effectiveness of operation of the power plant, however, only in the case when the ORC plant is supplied from the so called sealed heat source. In the present paper presented is the discussion of heat sources and on the base of the case study of two heat sources, namely the rate of heat of thermal oil from the boiler and the rate of heat of hot air from the cooler of the dinkier from the cement production line having the same initial temperature of 260[degrees]C, presented is the influence of the heat source on the justification of application of internal regeneration. In the paper presented are the calculations for the supercritical ORC power plant with R365mfc as a working fluid, accomplished has been exergy changes and exergy efficiency analysis with the view to select the most appropriate parameters of operation of the power plant for given parameters of the heat source.
    Źródło:
    Archives of Thermodynamics; 2012, 33, 3; 51-63
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simplified exergy analysis of ship heating systems with different heat carriers and with the recovery of waste heat
    Autorzy:
    Zeńczak, Wojciech
    Powiązania:
    https://bibliotekanauki.pl/articles/240490.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ship’s power plant
    heating systems
    heat carrier
    exergy analysis
    systemy siłowni okrętowych
    systemy grzewcze
    nośnik ciepła
    analiza egzergii
    Opis:
    The application of waste heat from exhaust gas of ship’s main engines has become widely practiced as early as in the 1930s. Thus the increase of ship’s overall efficiency was improved. Nowadays all newly built ships of the 400 gross tonnage and above must have specified energy efficiency design index, which is a measure for CO2 emissions of the ship and its impact on the environment. Therefore, the design of waste heat recovery systems requires special attention. The use of these systems is one of the basic ways to reduce CO2 emissions and to improve the ship’s energy efficiency. The paper describes the ship’s heating systems designed for the use of waste heat contained in the exhaust gas of self-ignition engines, in which the heat carriers are respectively water vapor, water or thermal oil. Selected results of comparative exergy analysis of simplified steam, water and oil heating systems have been presented. The results indicate that the oil heating system is comparable to the water system in terms of internal exergy losses. However, larger losses of exergy occur in the case of a steam system. In the steam system, a significant loss is caused by the need to cool the condensate to avoid cavitation in boiler feed pumps. This loss can in many cases cause the negative heat balance of ship during sea voyage while using only the exhaust gas boilers.
    Źródło:
    Archives of Thermodynamics; 2019, 40, 3; 211-228
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal analysis of heat and power plant with high temperature reactor and intermediate steam cycle
    Autorzy:
    Fic, A.
    Składzień, J.
    Gabriel, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/239939.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    cogeneration system
    high-temperature reactor
    exergy analysis
    gas heat pumps
    numerical simulation
    system kogeneracyjny
    reaktor wysokotemperaturowy
    analiza egzergii
    gazowe pompy ciepła
    symulacja numeryczna
    Opis:
    Thermal analysis of a heat and power plant with a high temperature gas cooled nuclear reactor is presented. The main aim of the considered system is to supply a technological process with the heat at suitably high temperature level. The considered unit is also used to produce electricity. The high temperature helium cooled nuclear reactor is the primary heat source in the system, which consists of: the reactor cooling cycle, the steam cycle and the gas heat pump cycle. Helium used as a carrier in the first cycle (classic Brayton cycle), which includes the reactor, delivers heat in a steam generator to produce superheated steam with required parameters of the intermediate cycle. The intermediate cycle is provided to transport energy from the reactor installation to the process installation requiring a high temperature heat. The distance between reactor and the process installation is assumed short and negligable, or alternatively equal to 1 km in the analysis. The system is also equipped with a high temperature argon heat pump to obtain the temperature level of a heat carrier required by a high temperature process. Thus, the steam of the intermediate cycle supplies a lower heat exchanger of the heat pump, a process heat exchanger at the medium temperature level and a classical steam turbine system (Rankine cycle). The main purpose of the research was to evaluate the effectiveness of the system considered and to assess whether such a three cycle cogeneration system is reasonable. Multivariant calculations have been carried out employing the developed mathematical model. The results have been presented in a form of the energy efficiency and exergy efficiency of the system as a function of the temperature drop in the high temperature process heat exchanger and the reactor pressure.
    Źródło:
    Archives of Thermodynamics; 2015, 36, 1; 3-18
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermodynamic assessment of crude distillation units: case studies of Nigeria refineries
    Autorzy:
    Osuolale, Funmilayo Nihinlola
    Anozie, Ambrose Nwora
    Powiązania:
    https://bibliotekanauki.pl/articles/240552.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    crude distillation unit
    exergy efficiency
    refineries
    thermodynamic analysis
    Opis:
    This paper presents the results of thermodynamic analysis of the crude distillation units of two refineries in Nigeria. The analysis was intended to assess the thermodynamic efficiencies of the refineries and proffer methods of improving the efficiencies. Presented results show the atmospheric distillation units of the refineries have 33.3% and 31.6% exergetic efficiencies and 86.5% and 74.6% energetic efficiencies, respectively. Modifications of the operating and feed conditions of the refineries resulted in increased exergetic efficiencies for as much as 62.3% and 38.7% for the refineries. Thermodynamic analysis of the refineries can bring about efficiency improvement and effectiveness of the refineries.
    Źródło:
    Archives of Thermodynamics; 2019, 40, 4; 83-102
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Energy efficiency – selected thermo-ecological problems
    Autorzy:
    Ziębik, Andrzej
    Stanek, Wojciech
    Powiązania:
    https://bibliotekanauki.pl/articles/239928.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    energy efficiency
    system analysis
    exergy
    thermo-ecology
    energy ecological
    efficiency
    Opis:
    The paper is devoted to some problems connected with last modification of EU directive on energy efficiency, viz.: free choice of the measure concerning the improvement of energy efficiency, i.e. final or primary energy consumption, corresponding energy savings or energy-consumption index; however without cumulative consumption or cumulative savings of primary energy. In EU directive it has been stressed the importance of measurements systems (reliable measurement information); but has not been recommended any advanced validation of measurements results, nor energy auditing or algorithms of calculating the energy savings due to improvement of energy efficiency concerning large industrial plants. Evaluation of complex buildings should be realized by means of the system method (input-output analysis). The separate problem is devoted to application of thermo-ecological approach in the analysis of complete results of improving the energy efficiency. Human activity is connected with the depletion of nonrenewable resources, including primary energy, due to not only production of consumer goods but also the necessity of compensating the unfavourable effects of harmful emissions from energy-technological processes. Therefore the index of energy-ecological efficiency has been proposed as the most competent evaluation of improvement energy efficiency of production processes and systems.
    Źródło:
    Archives of Thermodynamics; 2020, 41, 2; 277-299
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    System approach to the analysis of an integrated oxy-fuel combustion power plant
    Autorzy:
    Ziębik, A.
    Gładysz, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/240507.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    system approach
    input-output analysis
    oxy-fuel combustion
    cumulative energy
    exergy consumption
    system exergy losses
    thermoecological cost
    zarządzanie jakością
    analiza wejścia-wyjścia
    spalanie w tlenie
    energia skumulowana
    zużycie egzergii
    straty egzergii
    koszt termoekologiczny
    Opis:
    Oxy-fuel combustion (OFC) belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2 emissions (e.g., steel or cement production). The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2 - Due to the limited adiabatic temperature of combustion some part of CO2 must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2 processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the 'input-output' method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative) exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost) of an advanced integrated OFC power plant.
    Źródło:
    Archives of Thermodynamics; 2014, 35, 3; 39-57
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-12 z 12

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies