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    Wyświetlanie 1-13 z 13
    Tytuł:
    Mathematical model of four-stroke combustion engine working process
    Autorzy:
    Ślęzak, M.
    Jankowski, A.
    Wojciechowski, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/246405.pdf
    Data publikacji:
    2007
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    combustion engine
    combustion engine thermodynamics
    working process
    mathematical modelling
    Opis:
    By defining the fluid's thermodynamic properties, the cycle can be simplified using various assumptions. A lot of models of the combustion engine process were developed that including the thermodynamics, turbulence, and chemical kinetics to predict thermodynamic parameters of the engines. Mathematical model the working process occurring in the cylinder of the four-stroke piston-combustion engine is an object of the paper. The following assumptions consisting in that thermodynamics system is an open thermodynamical system, in accepted model were taken into account. Generalised mathematical model of the working process in the cylinder of the piston-four-stroke combustion engine was worked out. Dependences describing instantaneous volume of the working charge in the cylinder, equation of the balance of the of the working charge quantity in the cylinder and state equation of the working charge in the cylinder were considered at formulating of assumptions. Values of coefficients for each component processes of working cycle with taking into consideration of the dependence concerning the compression process , the combustion process, and expansion process after finishing of the combustion process were an object of worked out mathematical model. For nonstationary processes formulating working cycle of the engine realized during openings of valves (the open system), the quantity and composition of the working charge in the cylinder, its specific heat and temperature are variable. The temperature difference between the working charge and walls temperature of borderering the space of the cylinder was taken into account, too. Generalized mathematical model of the working process in the cylinder of the piston- four-stroke combustion engine applying for the theoretical analysis of the working process in the combustion engine, as well as for working out of experimental results was elaborated.
    Źródło:
    Journal of KONES; 2007, 14, 3; 587-595
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical investigation of lambda-value prechamber ignition in heavy duty natural gas engine
    Autorzy:
    Pielecha, Ireneusz
    Powiązania:
    https://bibliotekanauki.pl/articles/2097459.pdf
    Data publikacji:
    2020
    Wydawca:
    Polskie Towarzystwo Naukowe Silników Spalinowych
    Tematy:
    turbulent jet ignition
    combustion thermodynamics
    combustion process indicators
    numerical simulation
    turbulentny zapłon odrzutowy
    termodynamika spalania
    wskaźniki procesu spalania
    symulacja numeryczna
    Opis:
    Turbulent Jet Ignition systems are mainly dedicated to the combustion of lean mixtures of natural gas in heavy duty engines. The use of such a system in combination with lean mixtures leads to an increase in its overall efficiency. The article presents simulation analyzes of the impact of the air excess coefficient occurring in prechamber on the combustion process: combustion indicators and emission indicators. Tests on a single-cylinder engine with a displacement of about 4 dm3 at medium mixture (IMEP = 1.0 MPa) were carried out using the AVL Fire software. It was found that the incineration of global lean mixtures (λ = 2) is effective when initiating this process (in the prechamber) with a charge of a stoichiometric composition. A strong relationship was found between the thermodynamic indicators in both prechamber and main chamber and the air excess coefficient initiating combustion.
    Źródło:
    Combustion Engines; 2020, 59, 2; 31--39
    2300-9896
    2658-1442
    Pojawia się w:
    Combustion Engines
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of mass transfer in marine engine with prechamber combustion spark ignition system
    Autorzy:
    Pielecha, Ireneusz
    Powiązania:
    https://bibliotekanauki.pl/articles/2128135.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    marine engine
    prechamber combustion spark ignition
    combustion process modeling
    combustion thermodynamics
    silnik morski
    zapłon iskrowy spalania w komorze wstępnej
    modelowanie procesu spalania
    termodynamika spalania
    Opis:
    The development of combustion systems construction is associated with the possibility of increasing the thermal or overall efficiency of an internal combustion engine. The combustion systems currently in use (mainly related to direct fuel injection) are increasingly being replaced by hybrid systems, including direct and indirect injection. Another alternative is the use of prechambers in new combustion systems. This article concerns the thermodynamic aspect of this issue – namely, the assessment of the inter-chamber f low of a marine engine equipped with a prechamber combustion spark ignition system. The research was carried out using mainly one-dimensional simulation apparatus, and detailed analyses were presented using three-dimensional modeling. The tests included the engine model at medium load. Differences in mass f lows were shown at different diameters and different numbers of holes from the preliminary chamber (while maintaining the same cross-sectional area). Similar values of excess air coefficient during ignition of the fuel dose in the prechamber were observed, which resulted in changes in the f low between the prechamber and the main chamber. The differences in mass f low affected the temperatures achieved in the individual combustion chambers. Based on three-dimensional analyses, the mass transfer rate between the chambers and the temperature distribution were assessed during fuel ignition initiated in the prechamber.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 2; e136744, 1--8
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of mass transfer in marine engine with prechamber combustion spark ignition system
    Autorzy:
    Pielecha, Ireneusz
    Powiązania:
    https://bibliotekanauki.pl/articles/2173605.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    marine engine
    prechamber combustion spark ignition
    combustion process modeling
    combustion thermodynamics
    silnik morski
    zapłon iskrowy spalania w komorze wstępnej
    modelowanie procesu spalania
    termodynamika spalania
    Opis:
    The development of combustion systems construction is associated with the possibility of increasing the thermal or overall efficiency of an internal combustion engine. The combustion systems currently in use (mainly related to direct fuel injection) are increasingly being replaced by hybrid systems, including direct and indirect injection. Another alternative is the use of prechambers in new combustion systems. This article concerns the thermodynamic aspect of this issue – namely, the assessment of the inter-chamber f low of a marine engine equipped with a prechamber combustion spark ignition system. The research was carried out using mainly one-dimensional simulation apparatus, and detailed analyses were presented using three-dimensional modeling. The tests included the engine model at medium load. Differences in mass f lows were shown at different diameters and different numbers of holes from the preliminary chamber (while maintaining the same cross-sectional area). Similar values of excess air coefficient during ignition of the fuel dose in the prechamber were observed, which resulted in changes in the f low between the prechamber and the main chamber. The differences in mass f low affected the temperatures achieved in the individual combustion chambers. Based on three-dimensional analyses, the mass transfer rate between the chambers and the temperature distribution were assessed during fuel ignition initiated in the prechamber.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 2; art. no. e136744
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermodynamic cycle of combustion engine with hydrogen fuelling
    Autorzy:
    Sroka, Z. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/246368.pdf
    Data publikacji:
    2007
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    combustion engine
    thermodynamics
    hydrogen
    Opis:
    Shortage of crude oil gives the reason to look for any alternative engine fuel. One of them is the hydrogen, which will be the most lean fuel between others. Knowledge of hydrogen as an engine fuel, its properties, production and storage problems were analyzed in this paper. At the end own hydrogen concept based on Fiat engine 900ccm was shown. Theoretical comparison between thermodynamic cycles for engine run on conventional petrol and hydrogen was done. Results have given the green light to future development. Petroleum recourses run out have given the reasons to find alternative fuel. One of them could be hydrogen. According to analyze done in the project it can be found similarity between hydrogen engine with 1=1,0 to petrol engine with 1=0,9. Pressure of hydrogen charge is in this case higher of 0.42 mpa and there is calculated in strength of existing engine. The results of estimation show possibility to use hydrogen as a engine fuel, maybe first as a dual-fuel engine like LPG system. Emissions of nox for hydrogen engine as well as theoretical engine work cycles for analyzed cases are illustrated in the engine.
    Źródło:
    Journal of KONES; 2007, 14, 3; 573-578
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of thermodynamical parameters of combustion engine working cycle
    Autorzy:
    Siemińska - Jankowska, B.
    Ambrozik, A.
    Jankowski, A.
    Ślęzak, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/246372.pdf
    Data publikacji:
    2007
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    combustion engine
    engine thermodynamics
    engine working cycle
    Opis:
    Thermodynamics systems may be classified as isolated, closed, or open based on the possible transfer of mass and energy across the system boundaries. An isolated system is one that is not influenced in any way by the surroundings. This means that no energy in the form of heat or work may cross the boundary of the system. In addition, no mass may cross the boundary of the system. A thermodynamic system is defined as a quantity of matter of fixed mass and identity upon which attention is focused for study. A closed system has no transfer of mass with its surroundings, but may have a transfer of energy (either heat or work) with its surroundings. An open system is one that may have a transfer of both mass and energy with its surroundings. Described system being an object of the paper is an open system for some phenomena. An object the paper is the thermodynamical analysis of the filling process of the cylinder which occurs in calculated period from the percussion cap of the position the piston at TDC to it position at BDC, at constant average value of the pressure in the cylinder. During durations of the filling process of the cylinder, dirt of the working charge combustion products are not taken into account. One accepts that the quantity of the working charge in the established point placed on the compression line by piston BDC is equal quantity of the working charge in the end point of the filling process, answering to the start point of the real compression process. The state of the working charge in cylinder described is four parameters: a pressure, a temperature, quantity moles of the working charge and its volume. For appointment those parameters, earlier worked out dependences are put-upon.
    Źródło:
    Journal of KONES; 2007, 14, 3; 563-572
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Theoretical and real working cycle of four stroke piston engine
    Autorzy:
    Ambrozik, A.
    Jankowski, A.
    Slezak, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/243165.pdf
    Data publikacji:
    2007
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    combustion engine
    thermodynamics
    working cycle
    cylinder pressure
    Opis:
    The most important problems concerning analyses of generalized computational thermodynamical working cycle of the four-stroke combustion engine are result of the identification of real indicating diagram. The analysis of working cycle of the four-stroke combustion engine is realized from point of view heat efficiency, the average theoretical cycle pressure, as well as of the influence of the organization working cycle on the value of the maximum pressure in the cylinder of a combustion engine. A novel mathematical model reflecting elementary processes occurring in the cylinder of a combustion engine and connected with it intake and exhaust systems of engine were proposed. Thermodynamical working cycles of four-stroke piston engines, theoretical working cycle of a four-stroke piston engine, thermal efficiency of the theoretical thermodynamic generalised engine work cycle, mean theoretical pressure of the generalised thermodynamic work cycle of a combustion engine, maximum pressure of the theoretical thermodynamic work cycle of a combustion engine, comparative working cycles of piston engines, real working cycle of four-stroke piston engines are presented In het paper. The methods of analyses and calculations referring these engines work cycles were presented. These method show advisability and needs of using them to theoretical calculations and analyses of real work cycles. Generalized engine work cycle was proposed.
    Źródło:
    Journal of KONES; 2007, 14, 2; 9-18
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Preliminary investigations of the HCCI combustion system in a single cylinder research engine
    Autorzy:
    Motyl, K.
    Lisowski, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/246468.pdf
    Data publikacji:
    2007
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    thermodynamics
    internal combustion engines
    HCCI
    combustion process
    exhaust emission
    bio-fuel
    Opis:
    This paper describes the results of the preliminary experimental research of the HCCI combustion system in a single cylinder research engine fuelled by means of natural gas containing 95% methane. In this research, influence of the initial temperature of the charge and mixture composition on the maximum combustion pressure, maximum speed of pressure growth, selfignition delay time, combustion time, maximum combustion temperature, heat release and combustion efficiency have been studied. The paper contains: description of the engine modification to adopt it for HCCI operation requirements, applied measurements equipment, selected results of the experimental research. The results shows that initial charge temperature and mixture composition (relative air/fuel ratio coefficient) have essential influence on the engine operating results. The experimental research has been conducted for the varied initial charge temperature from 140 centigrade up to 210 centigrade and for varied relative air/fuel ratio coefficient 1=1; 1=1.5; 1=1.7; 1=2. Maximum charge pressure, maximum speed of pressure growth selfignition delay time was rather unaffected on the initial charge temperature increase beyond 200 centigrade. Previous and current author's research works have indicated that extremely low emissions and high combustion efficiencies are possible to reach if homogeneous charge compression ignition is applied.
    Źródło:
    Journal of KONES; 2007, 14, 3; 429-436
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of the thermodynamic combustion process in the engine supplied with gas having a low methane content
    Ocena parametrów termodynamicznych procesu spalania w silniku zasilanym paliwem o małej zawartości metanu
    Autorzy:
    Piasecki, D.
    Sroka, Z. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/134156.pdf
    Data publikacji:
    2013
    Wydawca:
    Polskie Towarzystwo Naukowe Silników Spalinowych
    Tematy:
    combustion engine
    thermodynamics
    methane
    silnik spalinowy
    termodynamika
    metan
    Opis:
    Exploitation of coal deposits is accompanied by extraction of methane, which can be a fuel for internal combustion engines. Methane with other gases states mixture with different chemical composition. It is called mine gas. Differences in the composition and the ability to lean combustion is explored in this study, where the authors have focused their attention on the selected thermodynamic parameters and operating indicators of internal combustion engine. The assessment was made on the virtual engine, which is a compilation of the actual engine, demonstrating the need for assistive technology such as charging, variable valve timing and variable compression ratio. They provide energy, despite the restrictions of the poor in the methane deposits to maintain the desired output power and reduced fuel consumption by ensuring environment-friendly operation.
    Eksploatacji złóż węgla kamiennego towarzyszy wydobywanie się metanu, który może stanowić paliwo do tłokowych silników spalinowych. Metan występuje w mieszaninie z innymi gazami i stanowi tzw. gaz kopalniany o zróżnicowanym składzie chemicznym. Różnice w składzie oraz możliwość spalania mieszanek ubogich jest przedmiotem rozważań w niniejszej pracy, gdzie autorzy skupili swoją uwagę na wybranych parametrach termodynamicznych i wskaźnikach pracy silnika spalinowego. Ocenę dokonano na wirtualnym silniku, będącym kompilacją silników rzeczywistych, wykazując konieczność stosowania technik wspomagających jak: doładowanie, zmienne fazy rozrządu czy zmienny stopień sprężania. Zapewniają one mimo ograniczeń energetycznych związanych z ubogimi w metan złożami gazu kopalnianego utrzymanie na pożądanym poziomie mocy paliwowej, a przez zmniejszone zużycie paliwa zagwarantowanie proekologicznej eksploatacji.
    Źródło:
    Combustion Engines; 2013, 52, 3; 800-805
    2300-9896
    2658-1442
    Pojawia się w:
    Combustion Engines
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Novel method appointing of the effective heat release coefficient during combustion process based on real indicator diagram
    Autorzy:
    Jankowski, A.
    Ambrozik, A.
    Jankowska-Sieminska, B.
    Ślęzak, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/244287.pdf
    Data publikacji:
    2007
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    combustion engine
    working cycle
    thermodynamics
    indicator diagram
    heat release
    Opis:
    An object of the paper is a novel method of effective heat release coefficient appointing during combustion process of the based on the real indicator diagram. The process quality of the heat release during process of combustion is evaluated by value of the effective heat release coefficient. Accepted assumptions at appointing effective coefficient of heat release refer to acceptable that thermodynamical parameters of the working charge according to points of the real indicator diagram and the computational diagram are such the same, the maximum pressure of real working cycle of the engine is equal to the pressure of the computational cycle, work of the working charge performed in period from point of closing of the inlet valve to point of the beginning of the exhaust process are for both considered working cycles equal, heat values of the carried to the real and computational cycle are such the same. The method of appointing of the self-ignition delay period is presented in the paper, using to this end intersection point of two graphs of temperature course of the working charge prepared for the first phase of combustion process. Other methods appointing characteristics is suggested in paper basing on the real indicator diagram. The graphic illustration of the preparing method of characteristics of the relative quantity of the heat release during combustion process is illustrated in paper.
    Źródło:
    Journal of KONES; 2007, 14, 4; 133-142
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Termodinamicheskaja vozmozhnost povyshenija ehffektivnocti DVS
    Thermodynamics possibility of increase of efficiency of combustion engines
    Autorzy:
    Podznoev, G.
    Abdulgazic, U.
    Zharik, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/77937.pdf
    Data publikacji:
    2014
    Wydawca:
    Komisja Motoryzacji i Energetyki Rolnictwa
    Tematy:
    diesel engine
    thermodynamics
    combustion engine
    exhaust gas
    kinetics
    pollutant emission
    Źródło:
    Motrol. Motoryzacja i Energetyka Rolnictwa; 2014, 16, 1
    1730-8658
    Pojawia się w:
    Motrol. Motoryzacja i Energetyka Rolnictwa
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Regarding the Influence of High Frequency Combustion Instabilities on Operation of Solid Rocket Motors
    Autorzy:
    Safta, D.
    Vasile, T.
    Ion, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/403482.pdf
    Data publikacji:
    2011
    Wydawca:
    Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
    Tematy:
    thermodynamics of rocket propulsion
    unsteady solid propellant combustion
    combustion instabilities
    pressure-coupled response
    rocket motor
    operation stability
    Opis:
    High frequency combustion instabilities imply a major risk for the solid rocket motor's stable operation and they are directly linked to the response of the solid propellant to the pressure coupling. Our paper aims at defining a linearized onedimensional flow study model of the solid propellant rocket motors' disturbed functioning analysis. Experimental researches were done with an adequate setup, built and improved in our lab, functioning on the basis of the nozzle throat intermittent modulating technique developed by ONERA researchers, able to evaluate the propellant response by the interpretation of the pressure oscillations damping in terms of propellant response.
    Źródło:
    Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa; 2011, 2, 1 (3); 7-24
    2081-5891
    Pojawia się w:
    Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Badanie wpływu wodorku glinu na skład chemiczny produktów i ciepło spalania złożonych paliw rakietowych
    Investigation of the Influence of Aluminium Hydride AlH3 on the Chemical Composition and Heat of Combustion of Composite Propellants
    Autorzy:
    Papliński, A.
    Zygmunt, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/403835.pdf
    Data publikacji:
    2014
    Wydawca:
    Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
    Tematy:
    termodynamika
    złożone paliwa rakietowe
    wodorek glinu
    produkty spalania
    thermodynamics
    composite propellant
    aluminium hydride
    combustion parameters
    Opis:
    W pracy przedstawione zostały wyniki analizy składu chemicznego oraz parametrów termodynamicznych produktów spalania złożonych paliw rakietowych zawierających wodorek glinu AlH3. Rozpatrywane są paliwa oparte na chloranie(VII) amonu (NH4ClO4), w których jako lepiszcze stosowany jest kauczuk typu HTPB. Jako składniki energetyczne paliwa rozpatrywane są Al i AlH3. Przedmiotem pracy jest zbadanie, w jaki sposób zastąpienie Al przez AlH3 wpływa na skład chemiczny i właściwości produktów spalania. Skład chemiczny i parametry termodynamiczne produktów spalania określono za pomocą programu obliczeniowego MWEQ. Przy zachowaniu tego samego udziału masowego, wprowadzenie AlH3 zamiast Al prowadzi do obniżenia temperatury produktów przemiany, wzrasta ilość moli produktów w stanie gazowym, odniesiona do jednostki masy paliwa. Uzyskane wyniki potwierdzają przydatność wodorku glinu AlH3 jako perspektywicznego składnika energetycznego paliw rakietowych.
    The influence upon chemical composition and heat of combustion of composite propellant that occurs as a result of substitution of aluminium by its hydride AlH3 is investigated. Propellants based on ammonium chlorate(VII) (NH4ClO4) modified by standard HTPB binder are considered. Chemical composition and thermodynamic parameters of combustion products are evaluated by MWEQ computer program supplied with large species database. The particular attention is paid to proper choose of thermodynamic data describing temperature dependence of heat capacity, enthalpy and entropy of chemical compounds belonging to Al-Cl-O-H group. The alteration of chemical composition and temperature of combustion products that is followed by replacement of Al by AlH3 is illustrated in a quantitative mode. The prospective applicability of AlH3 as an energetic component of composites propellants is confirmed.
    Źródło:
    Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa; 2014, 5, 1 (15); 41-50
    2081-5891
    Pojawia się w:
    Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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