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EN
Diverse forms of environmental pollution arise with the introduction of materials or energy that exert adverse effects on human health, climate patterns, ecosystems, and beyond. Rigorous emission regulations for gases resulting from fuel combustion are being enforced by the European Union and the International Maritime Organization (IMO), directed at maritime sectors to mitigate emissions of SOx, NOx, and CO2. The IMO envisions the realisation of its 2050 targets through a suite of strategies encompassing deliberate reductions in vessel speed, enhanced ship operations, improved propulsion systems, and a transition towards low and zero-emission fuels such as LNG, methanol, hydrogen, and ammonia. While the majority of vessels currently depend on heavy fuel or low-sulphur fuel oil, novel designs integrating alternative fuels are gaining prominence. Technologies like exhaust gas purification systems, LNG, and methanol are being embraced to achieve minimised emissions. This study introduces the concept of a high-power combined ship system, composed of a primary main engine, a diesel engine, and a steam turbine system, harnessing the energy contained within the flue gases of the main combustion engine. Assumptions, constraints for calculations, and a thermodynamic evaluation of the combined cycle are outlined. Additionally, the study scrutinises the utilisation of alternative fuels for ship propulsion and their potential to curtail exhaust emissions, with a specific focus on reducing CO2 output.
EN
The article focuses on the problem of loading the combustion chamber of diesel engine pistons together with the method of its optimization using the DuralBowl technology. Along with the growing requirements of exhaust emission standards, the increasing competition in the efficiency of internal combustion engines, the load on the combustion pistons increases due to the increase in pressure and temperature of fuel combustion and the tendency to slim the structure. Numerical analyzes and analyzes of damaged pistons in diesel engines have shown that one of the places most exposed to piston damage are the combustion chambers. There is a concentration of thermomechanical stress at the edge of the combustion chamber, which may lead to the destruction of the piston and the necessity to carry out overhaul of the drive unit. One of the technologies that optimizes the strength of this zone is the DuralBowl local remelting process. This process allows for several timesimprovement in the fatigue strength of pistons in internal combustion engines. The article analyzes the thermomechanical load on the combustion chamber along with the impact of this load on the durability of pistons in diesel engines. An analysis of the DuralBowl process was also performed, aimed at eliminating the negative effects of loading the combustion chamber, extending the piston life. The analysis focused on the microstructure of the material before and after the DuralBowl process.
EN
Diesel engine components in the combustion chamber have been exposed to cyclic loadings under environmental effects, including high temperatures and corrosive fluids. Therefore, knowing the corrosion-fatigue behavior of materials is essential for designer engineers. In this article, pure fatigue and corrosion-fatigue behaviors of the piston aluminum alloy have been experimentally investigated. For such an objective, as-cast and pre-corrosive standard samples were tested by the rotary bending fatigue machine, under 4 stress levels. Some specimens were exposed to the corrosive fluid with 0.00235 % of the sulfuric acid for 100 and 200 hours. The results showed higher weight losses for 200 hours immersion times. As another result, it could be concluded that the lifetime decreased in pre-corrosive samples for both 100 and 200 hours of the immersion time, compared to that of as-cast specimens. However, such a lifetime reduction was more significant for 200 hours of the immersion time, especially within the high-cycle fatigue regime (or lower stress levels). Under high stress levels, both pre-corrosive sample types had almost similar behaviors. The field-emission scanning electron microscopy images of specimen fracture surfaces indicated that the brittle region of the fractured surface was larger for specimens after the 200 hours of corrosion-fatigue testing than the other specimen.
PL
Przedstawiono wyniki badań dotyczących wpływu wody zdyspergowanej w mikroemulsji paliwowej na zmianę okresu jej samozapłonu. Określono wybrane właściwości fizyczno-chemiczne oleju napędowego (ON) oraz testowanych mikroemulsji zawierających 4 lub 8% mas. wody destylowanej. Paliwa te wykorzystano do zasilenia silnika badawczego firmy AVL. Wyniki potwierdziły, że obydwie testowane mikroemulsje wodno-paliwowe charakteryzowały się mniejszą skłonnością do samozapłonu niż ON.
EN
Gas oil and its aq. microemulsions (4 and 8% by mass) were tested as fuel in diesel engine. Both tested microemulsions had lower ability for self-ignition than the gas oil. Selected phys.-chem. properties of tested fuels were detd.
5
Content available remote Measurement and diagnostic system for marine engines
EN
The Scheduled Maintenance System allows ship-owners and operators to plan, carry out and document the maintenance and repair of equipment and mechanisms on board the ship at intervals in accordance with the class requirements imposed by the Classification Societies and the manufacturer of the equipment. In order to develop the research capabilities of the Faculty of Marine Engineering of Gdynia Maritime University, a Measurement and Diagnostic System has been developed to assess the technical condition of machinery and equipment in operation on board the ship. Modernization of measuring equipment, significantly expanded the research capabilities, which resulted in increasing the scope, improving quality, and speeding up the research and development work in the field of safety of operation and diagnostics of engine rooms and ship operation.
PL
Planowy System Utrzymania (PMS) pozwala armatorom i operatorom planować, wykonywać i dokumentować konserwację i naprawy urządzeń i mechanizmów na statku w odstępach zgodnych z wymaganiami klasy narzuconych przez Towarzystwa Klasyfikacyjne i producenta tych urządzeń. W celu rozwoju możliwości badawczych Wydziału Mechanicznego Uniwersytetu Morskiego w Gdyni w zakresie prawidłowego przeprowadzenia badań zgodnie z PMS opracowano System Pomiarowo-Diagnostyczny do oceny stanu technicznego maszyn i urządzeń będących w eksploatacji na statku. Modernizacja urządzeń pomiarowych znacznie rozszerzyła możliwości badawcze, co zaowocowało zwiększeniem zakresu, poprawą jakości i przyspieszeniem prowadzonych prac badawczo-rozwojowych w zakresie bezpieczeństwa eksploatacji i diagnostyki siłowni okrętowych i eksploatacji statku.
EN
The article presents a method for determining the quality of spraying a mixture of oil and synthetic fuels obtained from the processing of polymer materials. Laboratory tests of physical parameters of such a mixture were carried out, which made it possible to determine the limit values for the volume fraction of synthetic fuels. The method of determining the suitability of this type of fuel takes into account the criterion numbers Re and Oh, which include physical parameters such as viscosity, density, and surface tension. The experimental part concerning the distribution of droplets of injected fuel and determination of Sauter Mean Diameter using laser diffraction confirmed the usefulness of the developed method for the assessment of the possibility of using a mixture of petroleum-based and synthetic fuels in self-ignition engines.
7
Content available Residual fuel atomization process simulation
EN
The process of atomization of fuel in engines with compression ignition is determining in organization of the combustion process, the result of which are the economic and environmental performance of the engine. One of the main parameters of the spray jet fuel is the mean droplet diameter. The article presents the results of analytical and experimental studies by the definition of mean diameter of Sauter roplet of atomized residual fuel IFO380.
EN
Plastics present a major threat to today's society and environment. Though mankind has awoken to this threat and responded with developments in creating degradable bio plastics, there is still no conclusive effort done to repair the damage already caused. In this regard, the catalytic depolymerization studied here presents an efficient, clean and very effective means of removing the debris that we have left behind over the last several decades. By converting plastics to fuel, we solve two issues, one of the large plastic seas, and the other of the fuel shortage. This dual benefit, though will exist only as long as the waste plastics last, but will surely provide a strong platform for us to build on a sustainable, clean and green future. The paper presents results of density, viscosity, cetane number, ignition temperature of 100% synthetic fuel and this fuel’s mixture with the diesel oil. The quality of the fuel-air mixture formation is best characterized by the SMD parameter – Sauter's average diameter of spray drops, and its value in analytical studies depends on the physical parameters of the fuel (density, viscosity, surface tension). The results of laboratory tests will be developed in terms of the use of the measured parameters of a synthetic fuel mixture to calculate SMD values and to correct analytical equations taking into account the actual SMD values measured by laser diffraction laboratory tests.
PL
W artykule przedstawiono wyniki badań układu, składającego się z generatora HHO współpracującego z silnikiem spalinowym, wyposażonym w górniczy układ dolotowo-wylotowy. Celem badań była identyfikacja parametrów użytkowych silnika, takich jak moc i moment obrotowy oraz określenie zawartości substancji szkodliwych w spalinach. Na podstawie wyników badań dokonano analizy wpływu generatora na pracę silnika spalinowego.
EN
Results of tests of the system consisting of HHO generator cooperating with diesel engine, equipped with special inlet-outlet system, are presented. Identification of engine operational parameters, such as power and torque, as well as determination of concentration of hazardous substances in exhaust gases were the tests objectives. Impact of generator on operation of diesel engine was analyzed on the basis of test results.
EN
The paper describes the problem of coal-water mixture combustion process in heavy duty diesel engines in the energetic sector application. In the future due to depletion of crude oil resources we have to foreseen another fuel for application in power plants. Large deposits of coal and lignite in the world enable to utilize these fuels in different thermal machines, especially in internal combustion engines. A carbon powder containing small molecules about 10–20 micrometers dissolved in water is good fuel for applying in large capacity engines in electrical plants. Aqueous emulsion of coal has possibility of good cooling of injectors cooling and has also good lubricity. Initial experimental tests done in the world indicate a higher thermal efficiency of engine fuelled by water coal emulsion than engine fuelled by diesel oil and also gas turbine driven by gas from coal gasification technology. The increased emission of CO2 can be reduced in the plants simply by chemical reduction. The paper explains thermochemical processes taking place in the engines during combustion process. The work parameters results obtained from calculations were compared with those obtained from CI engine fuelled by diesel oil. The paper is a certain challenge for finding a new fuel sources as a competition for crude oil and allows to get acquainted with new engine fuelling technology.
PL
W artykule przedstawiono stanowisko oraz przykładowe wyniki badań wizualizacyjnych przebiegu procesu wtrysku wybranych paliw do silników o ZS. Stanowisko to zbudowano w oparciu o stół probierczy firmy Bosch EPS-815 ( z którego zaadoptowany został napęd pompy wysokociśnieniowej) oraz komorę wizualizacyjną o stałej objętości umożliwiającą realizację procesu rozpylenia paliwa. Rejestracji rozwoju strugi paliwa realizowano przy użyciu systemu AVL VisioScope.
EN
The article presents the test stand and sample visualization results of injection process for selected fuels used in diesel engines. The test stand was built based on the Bosch EPS-815 test bench and the constant volume visualization chamber which allows the fuel spraying. From test bench the drive of high-pressure pump was adapted. Using the AVL VisioScope system the spray formation was recorded.
PL
Charakterystyka TD (Time Density), opracowana dla napędów spalinowych eksploatowanych w kopalniach węgla kamiennego, pozwala na sklasyfikowanie silnika i określenie reprezentatywnego cyklu badawczego oraz wagi poszczególnych faz tego cyklu. W artykule przedstawiono metodę sporządzania charakterystyk gęstości czasowej TD maszyn z silnikiem spalinowym oraz metody pośredniego i bezpośredniego określenia momentu obrotowego niezbędnego do sporządzenia charakterystyki TD.
EN
Time Density Characteristics (TD), developed for diesel engines operating in hard coal mines enables classification of engine and determining the representative testing cycle and weight of each phase of the cycle. The method for preparation of TD characteristics of diesel engines as well as indirect or direct determination of torque indispensable for development of TD characteristics, is presented.
PL
W pracy przedstawiono możliwości poprawy wskaźników pracy silnika spalinowego o zapłonie samoczynnym, pracującego na biegu jałowym i nieobciążonego, wyposażonego w układ zasilania paliwem oparty na rzędowej pompie wtryskowej sterowanej z układu elektronicznego. Taka konfiguracja umożliwia wpływ na wskaźniki pracy silnika przez zmianę parametrów wtrysku paliwa do komory spalania. W ten sposób istnieje możliwość zmiany szybkości narastania ciśnienia spalania w cylindrze silnika przy jednoczesnej poprawie stopnia nierównomierności pracy i wpływie na wskaźniki emisyjne silnika.
EN
The paper presents the possibilities to improve indicators diesel engine. This engine at idling speed and was unloaded, in addition, it features a fuel supply system based on in-line injection pump driven from the electronic circuit. This configuration allows the impact indicators of engine operating parameters, by changing the fuel injection into the combustion chamber. In this way it is possible to change the rate of pressure rise in the cylinder combustion engine, while improving the degree of inequality of work and impact on emission rates of the engine.
PL
W pracy przedstawiono wyniki analizy uszkodzeń wybranych elementów aparatury wtryskowej silników wysokoprężnych pojazdów samochodowych. Analiza oparta jest na danych zebranych w latach 2001-2010 w zakładzie napraw układów wtrysku paliwa. Identyfikacja uszkodzeń elementów aparatury wtryskowej, polegała na wykonaniu weryfikacji elementów aparatury wtryskowej oraz przeprowadzeniu wywiadu z użytkownikami na temat procesu eksploatacji pojazdów i stosowanego paliwa. Stwierdzono wzrost liczby uszkodzeń w latach 2004-2007. Dominującą przyczyną uszkodzeń filtrów tym okresie było zablokowanie na skutek stosowania dodatków do paliw w postaci niskiej jakości bioestrów oleju rzepakowego. Uszkodzenia wtryskiwaczy spowodowane były głównie przez stosowanie dodatku do paliwa w postaci surowego oleju roślinnego. Przyczyną uszkodzeń pomp wtryskowych było głównie stosowanie paliwa zanieczyszczonego cząstkami stałymi.
EN
The paper presents the results of failure analysis of chosen elements of diesel engines injection system. The analysis is based on the data collected in 2001-2010 at the factory specializing in fuel injection system repairs. Identification of damages of injection equipment elements was carried out by verification of injection equipment components and interviewing users about the process of operation of vehicles and used fuel. The significant increase of number of failures in 2004-2007 was observed. The dominant cause of filter failures was their blocking due to use of fuel additives in the form of low-quality rapeseed oil bio-esters. Failures of the injectors were caused mainly by fuel additive in the form of crude vegetable oil. The injection pumps were damaged mainly due to solid contaminations in fuel.
EN
The paper presents comparative analysis of energetic possibilities of different ships with close parameters of displacement and operational ailing range, for selected type of main engine. Analysis is related to three types of ships, i.e. bulk carrier, tanker and container ship, with assumed displacement at level of 120 000DWT and typical for that ships sailing speed. The analysis concerns shipping route from Gdynia to Shanghai. First step of conducted analysis was based on elaboration of the list of contemporary similar ships for every class, their general dimensions, dimensional coefficients, and subsequently evaluation of hulls resistances using Holtrop – Mennen Method necessary for calculation of propulsive power, main engines’ selection, most convenient for every type of ship and calculation of trips durations and fuel consumptions. All calculations were done assuming typical cruising speed for considered types of ships, it means 25 knots for container ships and 15 knots for tankers and bulkers. Results of carried out calculations lets come to the conclusion that total time of trip duration of container ship is 1.5 times shorter and fuel consumption is 2.5 times higher comparing with tankers and bulk carriers going on the same trip. Taking under consideration constantly growing prices of heavy oil, that situation is inconvenient from economical point of view. Above facts explains general trend to reduce speed of container ships presented by almost all shipping companies. The way of speed’s reduction is decreasing of continuous power rate of main engine, what is related to necessity of blinding or dismounting some numbers of turbochargers. Hypothetic example of such operation and its impact at operational properties were analysed, and results showed, that exploitation parameters of the container ship begun closer to bulk carriers and tankers but could not achieve proper level of efficacy due to not optimal hull shape and engine characteristic.
EN
Environmental emissions and efficiency of a direct injection diesel engine fueled with fatty acid methyl esters (FAMEs) have been experimentally investigated and compared with petro-diesel. Rubber seed oil methyl ester, cotton seed oil methyl ester, neem oil methyl ester, and mahua oil methyl ester were used as fuels. The brake specific fuel consumption, brake thermal efficiency, and exhaust gas temperature, nitrogen oxides, carbon monoxide, hydrocarbons, and smoke emissions were investigated. Mahua oil methyl ester exhibits higher brake thermal efficiency compared to other FAMEs. The NOx was found to be higher, while CO, HC, and smoke emissions of rubber seed oil methyl ester were lower than the other fuels at all loads.
PL
Spełnienie wymagań poziomu emisji związków toksycznych w gazach odlotowych silników z zapłonem samoczynnym możliwe jest przy zastosowaniu wstępnej katalityczno-turbulizacyjnej obróbki paliwa. W artykule przedstawiono wyniki badań silnika z bezpośrednim wtryskiwaniem mieszaniny paliw ropopochodnych i pochodzenia roślinnego dla dwóch wersji układu turbulizacyjnego wtryskiwaczy paliwowych, które wskazują na poprawę parametrów efektywnych (obniżenie jednostkowego zużycia paliwa o 8%) jak i ekologicznych pracy silnika (obniżenie emisji NOx o 15%).
EN
The reduction of unit fuel consumption and exhausts toxic emission in the diesel engines was possible by implementing preliminary catalytic and turbulized fuel treatment that takes place directly in the fuel injector The article presents the results of tests of direct injection diesel engines on diesel fuel and mixtures with biofuel for two versions of turbulized. Preliminary fuel treatment results in the average reduction of unit fuel consumption of those engines by 8%, while toxic emission of nitrogen oxides drops by 15%.
EN
The paper attempts to distinguish types of IDID (Internal Diesel Injector Deposits) with regard to the mechanism of formation, factors facilitating their formation and the method of identification. Investigations into their formation mechanism have been discussed in the paper. The results of the investigations into the chemical nature and probable source of these deposits have also been discussed. It has been pointed out that modern common rail fuel injection systems might be less tolerant to deposits due to tighter fitting tolerances, lower mass of parts and sophisticated injection strategies. Various approaches to IDID formation counteracting have also been discussed.
PL
W artykule przedstawiono próbę podziału wewnętrznych osadów wtryskiwaczy paliwa na typy, biorąc pod uwagę mechanizmy ich tworzenia, czynniki sprzyjające ich powstawaniu oraz sposoby identyfikacji. Zaprezentowano badania dotyczące mechanizmów tworzenia takich osadów. Opisano także wyniki badań natury chemicznej i prawdopodobnych źródeł powstawania osadów. Zwrócono uwagę, że nowoczesne systemy wtrysku paliwa typu common rail są mniej odporne na oddziaływanie osadów ze względu na mniejsze tolerancje wykonawcze, mniejszą masę elementów roboczych i zaawansowane strategie wtrysku paliwa. Opisano też różne sposoby przeciwdziałania tworzeniu się osadów typu IDID.
EN
Large deposits of coal and lignite in the world enable to utilize as fuel in different thermal machines, especially in internal combustion engines. A carbon powder containing small molecules about 5–10 micrometers dissolved in water is good fuel for applying in large capacity engines in electrical plants. Aqueous emulsion of coal has possibility of good cooling of injectors cooling and has also good lubricity. The paper gives necessary information about obtaining of water-coal emulsion, its physical properties and technical realization of fuelling system. Initial experimental tests indicate a higher thermal efficiency of engine fuelled by water coal emulsion than engine fuelled by diesel oil and also gas turbine driven by gas from coal gasification technology. The in-creased emission of CO2 can be reduced in the plants simply by chemical reduction. The paper explains thermo-chemical processes taking place in the engines during combustion process. The work parameters results obtained from calculations were compared with those obtained from CI engine fuelled by diesel oil. The paper is a certain challenge for finding a new fuel sources as a competition for crude oil and allows to get acquainted with new engine fuelling technology.
PL
Duże pokłady węgla kamiennego i brunatnego na świecie umożliwiają wykorzystanie jako paliwa w rozlicznych maszynach cieplnych, szczególnie w tłokowych silnikach spalinowych. Sproszkowany węgiel zawierający małe drobiny około 5–10 mikrometrów rozpuszczony w wodzie jest dobrym paliwem do zastosowania w silnikach Diesla o dużej pojemności w elektrowniach. Wodny roztwór węgla umożliwia dobre chłodzenie wtryskiwacza oraz wykazuje również dobrą smarność. Artykuł podaje niezbędne informacje o otrzymywaniu emulsji węglowo-wodnej, podaje jej właściwości fizyczne oraz techniczną realizację takiego systemu zasilania. Wstępne badania doświadczalne wykazały większą sprawność cieplną silników zasilanych taką emulsją niż silniki zasilane olejem napędowym oraz turbin gazowych zasilanych produktami zgazowywania węgla. Większa emisja CO2 może być zredukowana w elektrowniach przez chemiczną redukcję albo sekwestrację. Artykuł wyjaśnia procesy termochemiczne występujące w procesie spalania takich silników. Parametry robocze silnika zasilanego emulsją węglowo-wodną otrzymane z symulacji zostały porównane z parametrami silnika zasilanego olejem napędowym. Artykuł jest próbą znalezienia nowego źródła paliwa jako konkurenta w stosunku do ropy naftowej i pozwala zaznajomić się nową techniką zasilania silnika spalinowego.
PL
W ramach artykułu przestawiono analizy statystyczne rodzajów napraw realizowanych w analizowanej firmie obejmujące okres pięciu lat. Analiza jest oparta na bazie danych (SQL), w której zapisywane są wszystkie informacje dotyczące realizowanych zleceń. W ramach analiz określono strukturę zbioru naprawianych pojazdów oraz przeprowadzono analizę najczęstszych usterek pojazdów.
EN
The article presents a statistical analysis of car repair data gathered by an examined company over five-year time interval. It is based on a SQL database which contains information about all realized orders. The analysis defines the structure of the set of repaired car makes and additionally to find the most frequent vehicle defects.
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