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EN
The paper presents the results of model and empirical research on the influence of the thermal state of a diesel engine (oil temperature) on its indicated (thermal) efficiency. The paper contains a test plan, including a description of the test object, test equipment, and measurement points on a real object. In the following part, the results of tests carried out on a real object (laboratory single-cylinder engine) and the results of model tests obtained on the original engine model are presented. The results are presented both in tabular and graphical form. The obtained test results allowed to determine the relative value of the influence of the engine's thermal state on its efficiency for various operating conditions (load and rotational speed).
EN
The article presents the results of research on the impact of feeding marine reciprocating internal combustion engines with blends of diesel fuel and n-butanol on their performance parameters. The study includes a research plan and empirical results, in which the engine efficiency and emissions of harmful compounds in the exhaust gases were determined. A promising aspect is also the decrease in the concentration of NOx, which has a positive impact on reducing the toxicity of exhaust gases. An important aspect of the passive defence of a vessel is the reduction of exhaust gas temperature under nominal loads.
EN
The demand for diesel fuel in the transport industry is expected to rise due to greenhouse gas laws and global economic expansion, necessitating the search for alternative energy sources. If light distillate fuels can match diesel fuel's efficiency and cleanliness at a more affordable cost, they could potentially enter the market. The aim of the investigations was to assess a single cylinder, four stroke diesel engine's performance using various blends of diesel (D) and heavy naphtha (N): D100%, D97.5%N2.5%, D95%N5%, D92.5%N7.5%, and D90%N10%. Tests were conducted at 3000 rpm and variable loads, revealing that the maximum permissible naphtha content in diesel oil (D100%) is 10%. Higher naphtha proportions led to misfire and instability under heavy loads. 100% diesel demonstrated the lowest brake-specific fuel consumption and higher thermal efficiency, while mixture of 90% diesel and 10% naphtha showed the highest fuel consumption and lower thermal efficiency.
PL
Oczekuje się, że zapotrzebowanie na olej napędowy w branży transportowej będzie zwiększało się ze względu na przepisy dotyczące gazów cieplarnianych i globalną ekspansję gospodarczą, co wymusza poszukiwanie alternatywnych źródeł energii. Jeżeli lekkie destylaty będą w stanie dorównać wydajności i czystości olejowi napędowemu, przy bardziej przystępnej cenie, mogłyby potencjalnie zostać wprowadzone na rynek. Celem badań była ocena osiągów jednocylindrowego, czterosuwowego silnika wysokoprężnego stosując różne mieszanki oleju napędowego (D) i benzyny ciężkiej (N): D100%, D97.5% N2.5%, D95% N5%, D92.5% N7.5% i D90% N10%. Badani przeprowadzono przy 3000 obr/min i zmiennym obciążeniu. Wykazano, że maksymalna dopuszczalna zawartość benzyny ciężkiej w oleju napędowym wynosi 10%. Większa zawartość benzyny w oleju napędowym prowadziła do przerw w zapłonie i niestabilności pod dużym obciążeniem.100% olej napędowy wykazał najniższe zużycie paliwa przy hamowaniu i wyższą sprawność cieplną, podczas gdy mieszanina 90% oleju napędowego and 10% benzyny ciężkiej wykazała najwyższe zużycie paliwa i niższą sprawność cieplną.
EN
The paper presents the experimental test results reflecting the comparative changes in the performance efficiency and emissions of the exhaust of a naturally aspirated, four-stroke, single-cylinder, air-cooled diesel engine due to its transition from neat rapeseed oil biodiesel to fuel blends prepared by mixing in various proportion (by volume) rapeseed methyl ester (B) and butanol (Bu). The lubricity properties of biodiesel-n-butanol fuel blends were studied using HFRR method. In contrast to previous works, the undertaken investigation is performed with a totally renewable, binary liquid biofuel blends. The purpose of the research is to reduce simultaneously the production of NOx emissions and the exhaust smoke with respect to neat biodiesel due to potentially improved homogeneity of combustible mixture and particulate matter emissions benefits suggested by the higher oxygen content (21.62 wt%) and the relatively lower carbon-to-hydrogen ratio (4.8) of the normal n-butanol. The tests revealed that the brake specific fuel consumption for the binary biodiesel-n-butanol fuel blends is always higher than that neat biodiesel produces under the same loading conditions. Maximum nitrogen oxide (NOx) emissions were obtained with the engine running on neat biodiesel (2290 ppm). At full (100%) load conditions, the lowest NOx emission was obtained with the engine running on a biofuel BBu20 blend. The lowest level of carbon monoxide emissions (CO) was observed, when engine running with the most butanol-oxygenated biofuel blend BBu20.The highest smoke opacity of the exhaust was obtained when the engine was fuelled with neat biodiesel and at full load.
EN
In the present work, biofuels produced from different raw fatty materials have been proposed as a dominant fuel component in biodiesel-diesel fuel blends. Biofuels were produced from pork lard and rapeseed oil by alkali transesterification using methyl alcohol. Blends of biofuels in volumetric proportions of 60 and 80% of the biocomponent and the remaining part of the conventional fuel were used in a compression ignition engine designed for medium-duty vehicles. The experiments were conducted at two engine rotational speeds (1500 and 3000 rpm, respectively) and a set of load conditions (50, 100, and 200 Nm, respectively). The tests focused on engine efficiency parameters (brake-specific fuel consumption and brake fuel conversion efficiency) as well as exhaust gas emissions (hydrocarbons, carbon monoxide, and carbon dioxide were determined). The obtained results indicate that blends containing biocomponents produced from pork lard were characterized by superior fuel consumption and efficiency results, compared to blends containing biocomponents produced from rapeseed oil. In terms of exhaust emissions, biocomponents produced from pork lard were also characterized by lower emission of all of the examined components compared to rapeseed methyl ester-diesel blends. This study proposes that fuel components obtained from custom (animal) raw-fatty material can be an effective substitute for commonly used rapeseed oil methyl esters.
6
PL
Nowe wymagania w zakresie minimalnego poziomu sprawności silników asynchronicznych wprowadzanych na rynek Unii Europejskiej – Rozporządzenie Komisji UE 2019/1781.
EN
The article presents theoretical research of the proposed system of fully independent valve control (FIVC) of the SI engine. The analysis included controlling the movement of the intake valves, which results in adjusting the mass of the fresh charge to the current engine load, as well as the movement of the exhaust valves, where the main aim is to keep the rest of the exhaust gas in the cylinder, i.e. implementation of internal EGR. The open theoretical Seiliger-Sabathe cycle with the classic throttle regulation of load is the reference cycle for assessment of benefits and study of the effectiveness of obtaining work as a result of application of the FIVC system. A comparative analysis of the effectiveness of application of the proposed system was carried out based on the selected quantities: fuel dose, cycle work, relative work of charge exchange and cycle efficiency. The use of the FIVC to regulate the SI engine load makes it possible to eliminate the throttle and thus reduce the charge exchange work, especially in the partial load range. And this then leads to an increase in internal and effective work, which in turn results in an increase in the effective energy efficiency of an engine operation.
EN
In the study AVL BOOST™ is used to perform a thermodynamic simulation of a six-stroke engine, being built by a research team based in Saudi Arabia. The six-stroke cycle consists of a standard four-stroke Otto Cycle followed by a heat recovering steam expansion cycle. Water is injected into the hot combustion chamber towards the end of the Otto expansion stroke producing steam, which is used to perform work on a piston. This process produces power using waste heat and therefore increases the overall efficiency of the engine. The Robin EY28D engine, which is a single cylinder, four-stroke, gasoline engine was used for this simulation study. The engine was modelled and converted into six-stroke engine in AVL BOOST. The results show that six-stroke engine is more efficient than four-stroke engine. In six-stroke engine, the engine power is increased by 33.1% and brake specific fuel consumption (BSFC) is decreased by approximately 16%. Where emissions are concerned, Nitrogen Oxide (NOx) emission from six-stroke engine is reduced by 80%, while the Hydrocarbon (HC) emission increases by 85% compared with the original 4-stroke. Moreover, the most efficient camshaft was found and designed according to the most efficient valve profile for this engine, which is combination of 60CA° of valve duration and 10 mm of valve lifting.
EN
Research of efficient and ecological parameters was carried out with compression ignition (CI) engine using diesel fuel and additionally supplied hydrogen and oxygen (HHO) gas mixture. HHO gas is produced by electrolysis when the water was dissociating. At constant engine‘s brake torque and with increasing HHO gas volumetric concentration in taken air up to 0.2%, engine efficient indicators varies marginally, however, with bigger HHO concentration these parameters becomes worse. HHO increases smokiness, but it decreases NOx concentration in exhaust gas. Numerical analysis of combustion process using AVL BOOST software lets to conclude that hydrogen, which is found in HHO gas, ignites faster than diesel fuel and air mixture. Hydrogen combustion before TDC makes a negative work and it changes diesel fuel combustion process – diesel ignition delay phase becomes shorter, kinetic (premixed) combustion phase intensity gets smaller.
EN
The article shows the processes that take place in an engine. The main terms connected with the compression ratio are explained. This document is a repetition of the problems connected with the functioning of the engine. The relationship between the compression ratio and the engine efficiency is described. Variables that influence the chart about thermodynamic cycle are described as well. This paper is a repetition of issues connected with functioning of the engine.
11
Content available remote Wpływ generatora ATEG na sprawność ogólną silnika ZI
PL
W artykule przeprowadzono analizę zwiększenia sprawności ogólnej silnika ZI przez odzysk energii odpadowej z gazów wylotowych przy wykorzystaniu generatora termoelektrycznego ATEG (Automotive Thermoelectric Generator) własnej konstrukcji. Do pomiaru mocy wygenerowanej przez moduły opracowano układ pomiarowy wraz z oprogramowaniem. Do badań wykorzystano silnik spalinowy nowoczesnej konstrukcji wykonany w technologii downsizingu - duża wartość objętościowego wskaźnika mocy silnika będącego stosunkiem mocy użytecznej do objętości skokowej. Na statycznym silnikowym stanowisku hamulcowym mierzono parametry termodynamiczne gazów wylotowych (temperatura, masowe natężenie przepływu), zużycie paliwa oraz napięcie i natężenie prądu wygenerowane przez moduły termoelektryczne. Na tej podstawie wyznaczono moc generatora ATEG i określono jej wpływ na zwiększenie sprawności ogólnej badanego silnika.
EN
The paper analyzes the increase of the overall efficiency of a spark ignition engine through energy recovery following the application of an Automotive Thermoelectric Generator (ATEG) of own design. At the engine dynamometer was fitted downsized spark ignition engine (with high effective power to displacement ratio). To measure power generated by the modules developed measuring system with the software. The thermodynamic parameters of the exhaust gas were measured on the engine test bed (temperature, exhaust gas mass flow) along with the fuel consumption and electric current generated by the thermoelectric modules. On this basis the power of the ATEG generator and its impact on the engine overall efficiency were determined.
12
Content available remote Analytical Performance Evaluation of Humphrey Cycle for Turbine Engine Application
EN
A continuous effort of engineers is being striving to improve efficiency and reduce specific fuel consumption. High hope lies in pressure gain combustion field (PGC). The Humphrey ideal cycle delivers more than 10% higher efficiency than the Brytona-Joule cycle. The impact of the pressure ratio, adiabatic exponent, intercooling and heat regeneration was investigated in the paper. Engine efficiency according to analytical calculation reached 45%. The engine based on the Humphrey cycle can be realized as an pulse powered turbine engine. It should work according repeating cycle that consists of filling, combustion and exhaust. The cycle has to be controlled by the valve timing system. Due to the variable thermal parameters in the chamber, an effective expansion of the energy impulse required the nozzles with various ratio of outlet cross section to minimum cross-sectional. More precise efficiency estimation of pulse power turbine engine could be done by means of three dimensional numerical analysis with assumed geometry of valve timing design.
EN
This article reports the results of a study into operating parameters of a system consisting of an SI engine and a powertrain in a Fiat Panda passenger car in the conditions of a variable load. The analysis was primarily concerned with the variability of fuel consumption resulting of the changing load applied to the driving wheels in the conditions of a test performed on chassis dynamometer for manual and automatic controlled transmission gear change The test bench included a dedicated driving cycle, which was developed as cycle with periodically changed constant linear speed of the car every 10 km/h. According to the vehicle set speed, the load on its wheels was determined by the basic resistance as rolling resistance, air resistance and resistance corresponding to road inclination. Each period of a drive cycle corresponding to steady state driving gave the average instantaneous values of drive system performance indicators. The waveforms of these indicators were recorded and then averaged and presented as representative points of the powertrain system that were analysed. The focus of the study involved the identification of the points characterized with the minimum specific fuel consumption and impact of type of powertrain control on emission of CO2 from passenger car SI engines.
EN
The paper aims at reviewing the evolution of the F1 engine technology and the associated regulatory framework governing the sport over the last 10 years. Technical regulations, in force since 2014, replaced the 2.4-liter V8 naturally aspirated engines with sophisticated hybrid units such as the 1.6-liter V6 turbocharged engines supported with energy management and recovery systems. Since 2014 the fundamental trend in the development of powertrains has been the advancement of their efficiency. Due to the fact that the fuel flow rate has been restricted, the maximum performance is now entirely dependent on the engine efficiency.
PL
W artykule zaprezentowano przegląd rozwoju technologii silników samochodów wyścigowych F1 i związane z nimi przepisy oraz regulacje w okresie ostatnich dziesięciu lat. Obowiązujące od 2014 r. przepisy techniczne wprowadziły w miejsce używanych do końca 2013 r. wolnossących silników V8 o objętości skokowej 2,4 dm3, złożone hybrydowe zespoły napędowe, obejmujące turbodoładowane silniki V6 o objętości skokowej 1,6 dm3 wspomagane przez systemy zarządzania i odzyskiwania energii. Od roku 2014 podstawowym kierunkiem rozwoju zespołów napędowych jest ich sprawność; ponieważ wielkość zużycia paliwa została zmniejszona, więc poprawa osiągów zespołów napędowych jest całkowicie uzależniona od ich sprawności.
PL
W artykule opisane zostały zagadnienia poprawy sprawności ogólnej spalinowego silnika z zapłonem iskrowym poprzez zastosowanie podwyższonego stopnia sprężania. Autorzy opisali znane możliwości konstrukcyjne w zakresie umożliwiającym ruch głowicy cylindrowej, zastosowania tłoków dwuelementowych, mimośrodowego łożyskowania wału korbowego, zmiany wymiaru wykorbienia lub korbowodu, zastosowania dodatkowej komory spalania czy podziału wału korbowego i zastosowania przekładni. W końcowej części artykułu przedstawiono zestawienie podsumowujące opisane rozwiązania konstrukcyjne.
EN
In the article the issues to improve the efficiency of the internal combustion spark ignition engine through with the used of high compression ratio were described. The authors construction possibilities in the area of enabling the movement of the cylinder head, use two-element pistons, the crankshaft eccentric bearing, changing the dimension of double crank or connection-rod, using an additional combustion chamber or division of the connection-rod and use of the transmission were shown. In the final part of the article summary of the described construction solutions was presented.
EN
In this paper, the existing methods to reduce the heat discharged by the engine were characterized and the efficiency of combustion piston engine was analysed, where it was shown the need and the potential for reducing the heat dissipated directly or indirectly to the surrounding atmosphere. The model of the engine cooling system for high coolant temperature developed through AMESim software was presented in this paper. The model of the cooling system was made based on test stand solution designed and built using original components and units diesel engine 4CT90. The simulation researches results of temperature course and pressure course were shown. In this paper was demonstrated that it is possible to maintain the assumed constant pressure of 0.3 MPa in the system and obtain it at the elevated liquid temperature leading to an increase in overall engine efficiency. These researches were carried out also on the experimental model stand, which confirmed the results obtained in simulation researches. Then 4CT90 engine test stand was described, where speed characteristics as a function of torque, power and specific fuel consumption and load characteristics as a function of the fractions of hydrocarbons, carbon monoxide and carbon dioxide, as well as specific and hourly fuel consumption were performed. Comparison of parameters and efficiency assessment of engine interacts with a traditional and pressure cooling system. The efficiency of the engine with the pressure and a traditional cooling system was evaluated.
EN
The paper presents an analysis of the heat balance combustion engine, which was shown that it is possible to increase its efficiency by reducing cooling losses, such as raising the temperature of the coolant. The presented research results show that it was possible to maintain the pressure in the system, and thus the temperature of the liquid on the assumed level for a longer period by changing the intensity of cooling. The increase of coolant temperature to 120°C had an effect an increase of economy of operation and an increase in the maximum engine torque and reduced the share of carbon monoxide and hydrocarbons at low load and low engine speed of its, and therefore outside the scope of the catalytic converter. Increased share of nitrogen oxides, which requires the use of additional and effectively reducing the nitrogen oxides.
PL
W referacie przedstawiono analizę bilansu cieplnego tłokowego silnika spalinowego, w której wykazano, że istnieje możliwość zwiększenia jego sprawności poprzez zmniejszenie strat chłodzenia, np. podwyższając temperaturę płynu chłodzącego. Przedstawiono wyniki badań, z których wynika, że możliwe było utrzymanie nadciśnienia w układzie, a tym samym temperatury cieczy o założonej wartości przez dłuższy okres zmieniając intensywność chłodzenia. Podwyższenie temperatury cieczy chłodzącej do 120°C wpłynęło na zwiększenie sprawności silnika oraz wzrost maksymalnego momentu obrotowego silnika oraz spowodowało zmniejszenie udziałów tlenku węgla i węglowodorów w spalinach podczas pracy z małym obciążeniem i małą prędkością obrotową. Zwiększyły się udziały tlenków azotu, co wymaga zastosowania dodatkowego i efektywnego układu redukującego tlenki azotu.
EN
Internal combustion engines, used for driving of different cars, occurs not only at full load, but mostly at the part load. The relative load exchange work at the full (nominal) engine load is significantly low. At the part load of the IC engine its energy efficiency ηₑ is significantly lower than in the optimal (nominal field) range of the performance parameters. One of the numerous reasons of this effect is regular growing of the relative load exchange work of the IC engine. It is directly connected with the quantitative regulation method commonly used in the IC engines. From the thermodynamic point of view - the main reason of this effect is the throttling process (causing exergy losses) occurring in the inlet and outlet channels. The known proposals for solving of this problem are based on applying of the fully electronic control of the motion of inlet, outlet valves and new reference cycles. The idea presented in the paper leads to diminishing the charge exchange work of the IC engines. The problem can be solved using presented in the paper a new concept of the reference cycle (called as eco-cycle) of IC engine. The work of the engine basing on the eco-cycle occurs in two 3-stroke stages; the fresh air is delivered only once for both stages, but in range of each stage a new portion of fuel is burned. Normally the charge exchange occurs once during each engine cycle realized. Elaborated proposition bases on the elimination of chosen charge exchange processes and through this the dropping of the charge exchange work can be achieved.
PL
Silniki spalinowe, stosowane jako jednostki napędowe samochodów, pracują nie tylko przy pełnym (nominalnym) obciążeniu, ale także (najczęściej) pod obciążeniem częściowym. Względna praca wymiany ładunku silnika przy jego pełnym obciążeniu jest stosunkowo niewielka. Przy obciążeniu częściowym energetyczna sprawność ηₑ silnika spalinowego jest znacznie niższa aniżeli przy jego pełnym (optymalnym) obciążeniu, co między innymi jest powiązane z wielkością pracy wymiany ładunku w układzie. Z termodynamicznego punktu widzenia przyczyną tych zmian jest proces dławienia (przepustnica, straty egzergii) głównie na dopływie do silnika, co jest efektem tzw. ilościowej regulacji silnika spalinowego. Przygotowywane są różne propozycje rozwiązań, prowadzące do efektywnego zmniejszenia pracy wymiany ładunku przy niskich obciążeniach silnika. Jednym z proponowanych prostszych rozwiązań w tym zakresie może być zastosowanie tzw. ekoobiegu, którego idea polega na zmniejszeniu liczby napełnień cylindra. Przedmiotem analizy są możliwości realizacyjne oraz uwarunkowania eksploatacyjne ekoobiegu silnika spalinowego. Zasadniczym warunkiem branym pod uwagę, było kryterium sprawności energetycznej ekoobiegu w stosunku do sprawności istniejących obiegów klasycznych, a w szczególności stwierdzenie możliwości zwiększenia sprawności układu, głównie w zakresie obciążeń częściowych silnika spalinowego. Wskazano na sposób kontroli i dobór warunków spalania w układzie.
EN
As an alternative to the familiar option of downsizing diesel engines, AVL has developed the so-called efficiency engine in collaboration with Renault. Because of the engine's moderate power density, its peak pressure requirements are lower in some areas than those of turbocharged gasoline engines. Consequently, its mechanical friction and fuel consumption can be significantly reduced, as the comparison with a conventional and a downsized diesel engine demonstrates.
PL
Firma AVL, przy współpracy z koncernem Renault, rozwinęła tzw. wysokosprawny silnik, jako rozwiązanie alternatywne dla znanej koncepcji downsizingu silników ZS. Z uwagi na umiarkowany objętościowy wskaźnik mocy silnika, maksymalne wartości ciśnienia w silniku są mniejsze w niektórych obszarach niż te dla turbodoładowanych silników ZI. W wyniku tego mogą być zmniejszone straty tarcia i zużycie paliwa, w porównaniu do konwencjonalnych i poddanych procesowi downsizingu silników ZS.
20
Content available remote Sprawność napędu w dwufazowym, rzeczywistym cyklu jezdnym pojazdu
PL
W niniejszym artykule zaprezentowano interesujące wyniki badań i obliczeń sprawności napędu różnych pojazdów w dwufazowym cyklu jezdnym. Jest to kontynuacja symulacyjnych obliczeń dla pojazdu samochodowego, gdy jedna z faz jest napędową o maksymalnej sprawności ogólnej silnika napędowego przy wybranym przełożeniu skrzyni biegów, a druga – nienapędowa: wybiegu lub rewersyjna.
EN
This paper presents interesting results of the research and calculations of drive efficiency in different vehicles in 2-phase driving cycle. This is a continuation of simulation calculations for a car where one of the phases means a driving phase with maximal overall engine efficiency with selected reduction ratios of the gearbox, whereas the other one is a non-driving phase of driving in neutral or reverse.
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