Wyniki wyszukiwania - BazTech

1

A new perspective on the assessment of the technical condition of complex technical systems: Five-valued classification on the example of a submarine propulsion system

Woźniak Marek

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

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2025

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Nr 3

99--116

EN

The present article addresses the issue of a reliability analysis and assessment of a submarine propulsion system using five-state classification. A model of the operational process of the technical object under diagnosis was developed in both graphical and analytical forms, based on five-valued diagnostics, which enables an unambiguous correlation between operational states and technical states defined. The proposed model incorporates the following subsets of operational states: full operability (S4), partial operability (S3), critical operability (S2), and pre-failure operability (S1), which reflect successive stages of the degradation and restoration processes. Particular emphasis is placed on an identification of the pre-failure state, which is especially significant in conditions of isolated operation, where early detection of degradation symptoms is crucial for preventing failures and ensuring task continuity. The integration of five-state classification with reliability modelling based on Markov processes enabled a determination of the state probabilities Pi(t), describing the proportion of time the system remains in each technical state over time t. Simulations, taking into account the operational profiles of diesel and electric engines, revealed their distinct degradation characteristics and the impact of maintenance intensity on sustaining high readiness levels. The results confirm that the use of the five-state classification improves diagnostic precision and supports operational decision-making, thereby providing an effective tool for reliability assessment and risk management in submarine propulsion systems. The approach presented has practical applicability in environments where maintaining technical operability directly affects the crew safety and operational effectiveness of the submarine.

2

Ślad węglowy modernizacji taboru autobusów miejskich na pojazdy elektryczne akumulatorowe i wodorowe

Fice Marcin, Komenda Danuta

Energetyka

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2025

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nr 4

258--268

PL

Ślad węglowy stanowi istotny wskaźnik oceny oddziaływania produktu lub usługi na środowisko, obejmując emisje gazów cieplarnianych w całym cyklu życia, a nie tylko bezpośrednie emisje dwutlenku węgla z pojazdów. W analizie uwzględniono główne gazy cieplarniane: dwutlenek węgla (CO2), metan (CH4) i podtlenek azotu (N2O), które są istotne w kontekście sektora transportu. W artykule przedstawiono wyniki obliczeń śladu węglowego miejskiej usługi transportowej w Wodzisławiu Śląskim, przeprowadzonych zgodnie z wytycznymi protokołu GHG (Greenhouse Gas Protocol). Analizie poddano zarówno istniejący tabor z silnikami Diesla, jak i scenariusze modernizacji floty na pojazdy elektryczne zasilane akumulatorowo oraz wodorowe. Obliczenia obejmowały emisje bezpośrednie (zakres 1), emisje pośrednie związane z zakupioną energią elektryczną (zakres 2) oraz inne emisje pośrednie, takie jak produkcja komponentów autobusów, źródła paliw i energii oraz działalność operacyjna przedsiębiorstwa transportowego (zakres 3). Wyniki wskazują, że całkowity ślad węglowy jest silnie uzależniony od źródła pochodzenia paliwa i energii. W analizowanym przypadku, transport określany jako „zeroemisyjny” może generować wyższy ślad węglowy w porównaniu z tradycyjnymi pojazdami z silnikami spalinowymi, szczególnie gdy energia elektryczna lub wodór pochodzą z nieodnawialnych źródeł. Dodatkowo, produkcja akumulatorów może znacząco zwiększyć całkowite emisje gazów cieplarnianych. Do przeprowadzenia obliczeń wykorzystano dane z kilkudziesięciu źródeł literaturowych oraz wyniki rzeczywistych testów autobusów o danych producentów. Analiza podkreśla również, że wyniki śladu węglowego mogą się różnić w zależności od zastosowanych źródeł danych i przyjętych założeń.

EN

The carbon footprint is a key indicator for assessing the environmental impact of a product or service, encompassing greenhouse gas emissions throughout the entire life cycle, not just the direct carbon dioxide emissions from vehicles. The analysis considers major greenhouse gases: carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), which are particularly relevant in the transport sector. This article presents the results of a carbon footprint assessment of municipal transport services in Wodzisław Śląski, conducted in accordance with the Greenhouse Gas (GHG) Protocol guidelines. The study covers both the existing diesel-powered bus fleet and scenarios for its modernization to battery-electric and hydrogen-powered vehicles. The calculations include direct emissions (Scope 1), indirect emissions from purchased electricity (Scope 2), and other indirect emissions (Scope 3) such as emissions related to the production of vehicle components, sources of fuels and energy, and the operational activities of the transport company. The results indicate that the total carbon footprint is highly dependent on the origin of the fuel and energy used. In the analyzed case, so-called “zero-emission” transport may result in a higher carbon footprint compared to conventional diesel-powered vehicles, particularly if the electricity or hydrogen is derived from non-renewable sources. Moreover, battery production can significantly increase total greenhouse gas emissions. The assessment was based on data from several dozen scientific sources and real-world tests of buses, including manufacturer data. The analysis also highlights that carbon footprint results may vary depending on the data sources and assumptions applied.

3

Performance and emissions of a diesel engine fueled by Tiska 68-based synthetic fuel blends

Mouzong Bongne Francis, Bencherif Mohamed, Ayissi Merlin Zacharie

Combustion Engines

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2025

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R. 64, nr 2

34--43

EN

This work compares and studies the performance and emissions of a single-cylinder diesel engine fuelled by diesel and blends of a fuel derived from used industrial oil. Tiska 48 used industrial oil is used as raw material. By transesterification of this oil, biodiesels were created and combined with diesel in proportions of 15%, 30% and 45%. Diesel engine emissions, performance, and combustion were calculated at a nominal speed of 1600 rpm and load variation. The procedure and experimental design for extracting the new fuel by transesterification are described in detail. The first part of the study focused on the identification and physicochemical characterization of the fuels in order to establish selection criteria for direct use on an engine test bench. The characteristics studied were liquid density, kinematic viscosity, dynamic liquid viscosity, acid number and flash point. A set of three mixing ratios was selected for fuel synthesis. The second part was devoted to bench tests carried out on a Kipor 178F diesel engine. Synthetic fuels were tested with 15%, 30% and 45% BT 68 fuel blends. A comparative study was carried out, highlighting engine performance and NOx, CO, BFCS and EGT emissions for each fuel used. Blending pure diesel with synthetic fuel reduced carbon monoxide and NOx emissions by 85% and 65%, respectively. The BFCS of the biodiesel combinations is in perfect agreement with that of pure diesel but slightly higher (around 9.12%) overall.

4

Experimental investigation of the impact of methanol-diesel blends on diesel engine emissions and performance

Hassan Qais Hussein, Al-Abboodi Hamid

Combustion Engines

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2025

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R. 64, nr 2

150--157

EN

In this study, the impact of methanol-diesel fuel blends on the performance and exhaust emissions of a four-cylinder, four-stroke, direct injection, turbocharged diesel engine was experimentally analyzed. This investigation was conducted in response to increasingly strict regulations on exhaust emissions for newly manufactured diesel engines. The blends used had methanol content ranging from 0% to 15% with 5% increments. Engine performance tests were conducted on a dynamometer, varying engine speed from 1000 min-¹ to 2700 min-¹. The results reveal that although all fuels exhibit increased power output with rising engine speed, incorporating methanol results in a power reduction of approximately 4% for M5, 9% for M10, and 13% for M15 compared to pure diesel. Conversely, the brake specific fuel consumption (BSFC) improves with methanol addition, decreasing by roughly 5%, 10%, and 14% for M5, M10, and M15, respectively, which suggests enhanced combustion efficiency. Furthermore, carbon monoxide (CO) emissions drop significantly with higher methanol content, showing reductions of about 13%, 27%, and 40% for the M5, M10, and M15 blends, respectively, relative to standard diesel. Balancing the observed trade-offs between power loss and efficiency gains, the 10% methanol blend (M10) emerges as the optimal fuel mixture, offering substantial improvements in fuel economy and emission reductions with only a moderate decrease in engine power.

5

Hydrogen with compressed natural gas in 1-cylinder diesel engine: Emission analysis

Bajerlein Maciej, Karpiuk Wojciech, Kurc Beata, Levchenko Dmytro, Smolec Rafał, Waligórski Marek

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 10

106--122

EN

HCNG is a fuel, which as a mixture of hydrogen (H₂) and compressed natural gas (CNG), combines the advantages of both gases. The addition of hydrogen shortens the combustion time, increases the flammability range and enables greater exhaust gas recirculation (EGR) while maintaining cyclic stability and low NOx emissions. As a result, HCNG can be used in most classic diesel engines. This fuel has a higher energy volumetric storage density than pure hydrogen, which reduces the need to transport large amounts of fuel. Disadvantages include the lack of appropriate infrastructure, fuel and vehicle standards and the need for additional safeguards. The aim of the study was to check the emission levels of a single-cylinder diesel engine powered by HCNG compared to conventional fuel. It has been shown that the use of HCNG effectively reduces CO emissions due to the lack of carbon in hydrogen and its high combustion rate, which intensifies the process and improves its efficiency. The higher hydrogen content further stabilizes methane combustion and increases the homogeneity of the mixture. HCNG also reduces hydrocarbon (HC) emissions, compensating for the ignition delay and slow speed of the CNG flame. At higher engine loads, these effects are more visible, leading to more efficient combustion. Particulate matter (PM) emissions are reduced due to the homogeneous mixture resulting from the high diffusivity of hydrogen. PM reduction is more visible at lower loads. Higher combustion temperatures in HCNG promote the formation of NOx, which results from the intensification of combustion by hydrogen and excess oxygen, according to the Zeldovich mechanism. By analyzing emissions, the authors showed the great potential of using HCNG in a diesel engine. At the same time, the main challenges that should be faced in order to popularize this solution were indicated.

6

Operating peculiarities of standard coolin g systems of engines at high altitudes

Myrzakhmetov Beibit, Sładkowski Aleksander, Mashatayeva Gulzada

Transport Problems

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2024

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T. 19, z. 4

59--68

EN

The item under test was the engine without its standard facility-based cooling systems, the lack of which makes it impossible to operate as a power unit of a vehicle in a great majority of experimental research of internal combustion engines at high altitudes. The findings may create a wrong impression of the range of power ratings and economic parameters of the engine when operating at high altitudes because changes in atmospheric conditions exert an effect on the running efficiency of its standard systems as well. It is established that the efficiency loss of the cooling system may cause a forced power limitation of the engine as a result of the experimental research of the diesel engine equipped with all standard facility-based systems at very high altitudes. Thus, the shortage of power may significantly exceed the power loss of the engine due to air density reduction at high altitudes.

7

Technical aspects of the selection of an engine-generator set for a dual-drive locomotive

Michalak Piotr, Urbański Patryk, Jakuszko Wojciech, Gallas Dawid, Stobnicki Paweł, Tarnawski Piotr

Combustion Engines

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2024

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R. 63, nr 2

97--105

EN

The use of dual-drive rolling stock is a relatively new solution in the railway market. Vehicles with such type of powertrain are more versatile because it combines the advantages of using diesel vehicles and electric vehicles that consume energy from overhead electric traction. The concept of using such vehicles is highly innovative and has many advantages. However, the design and construction process is more complicated and requires more work than in the case of conventional systems. This article presents the methodology and process of selecting an engine-generator set for a dual-drive locomotive. Indicators and procedures crucial in the process of selecting a dual-drive system for a locomotive, were described and evaluated. All the above mentioned in the work were used during the real design process of a fully Polish locomotive with both diesel and electric drives. The locomotive in Diesel mode was to have an output power of circa 1560 kW for cargo transport. Calculations for the locomotive's power balance are included, showing power losses in the system and for locomotive's own needs. It has been shown that in cargo transport 77% of the maximum engine power is used as tractive power, and in passenger transport 58.6%.

8

Investigations of the city bus powertrain efficiency

Wendeker Mirosław, Grabowski Łukasz

Combustion Engines

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2024

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R. 63, nr 1

134--139

EN

Research work on the energy efficiency of vehicles is driven, among other things, by limits related to fuel consumption and carbon dioxide emissions. This also applies to city buses, where fuel consumption averages between 25 and 30 dm3 per 100 km, which can be converted into approximately 87 kg CO2 per dm3. This article, therefore, presents the results of a study of the total efficiency of the power train of a city bus, taking into account the internal combustion engine, transmission, torque converter, and tire friction on the rollers. The test object was a 12-metre city bus equipped with diesel engines and an automatic gearbox. The tests were carried out on a chassis dynamometer by implementing the World Harmonized Vehicle Cycle (WHVC). The WHVC driving test is a synthesis of the vehicle's on-road speeds and consists of three stages: Urban, Rural, and Motorway. During the tests, the fuel consumption, vehicle speed, and power generated at the wheels of the bus were recorded. From this, efficiency was calculated as the ratio of the power measured at the wheels of the bus to the power contained in the fuel supplied to the engine. Efficiency was shown to range from 5 to 22%.

9

Combustion stability for early and late direct hydrogen injection in a dual fuel diesel engine

Siadkowska Ksenia, Barański Grzegorz

Combustion Engines

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2024

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R. 63, nr 1

89--98

EN

The paper presents an analysis of the experimental results of direct hydrogen injection in a dual-fuel diesel engine. The test object is a four-cylinder, four-stroke ADCR engine. The parameters like: indicated mean effective pressure, peak pressure, angle of maximum pressure and released heat were analyzed. Statistical analysis of the obtained results was carried out for each cylinder separately for four different hydrogen doses. Both early and late direct hydrogen injection were analyzed. The significance of the differences for each of the analyzed parameters and type of injection was determined. The stability of the combustion process was evaluated using the coefficient of variation CoV(IMEP).

10

Waste plastic oil as an alternative fuel: a review

Amardeep, Kumar Rakesh, Kumar Naveen

Archives of Thermodynamics

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2024

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Vol. 45, no. 1

87--97

EN

Today, with the high population density of the world, the energy demand is increasing continuously. Global dependency on fossil fuels is very strong and there is a compelling need to reduce our energy consumption in order to offset greenhouse gas emissions. Due to regularly increasing prices of fossil fuels alternative fuels are needed to fulfill the requirements of developing countries like India. Plastics in today's world have become crucial. They are excessively used in industry, as well as in households and other fields due to their lightweight, durability, and design flexibility. Plastic demand is growing day by day, which now poses a huge environmental threat. The current study summarizes the use of WPO (waste plastic oil) in the diesel engine and also concludes the combustion, performance, and emission parameters. After an exhaustive literature search, some interesting results have been found. The study reveals that when using WPO as an alternative source in a diesel engine, the combustion, performance, and emissions are similar to those using conventional diesel fuel. An enhanced BTE (brake thermal efficiency) and reduced emissions of unburned hydrocarbons (UBHC) and carbon monoxide (CO) are reported.

11

Use of butanol, pentanol and diesel in a compression ignition engine: A review

Kumar Deepak, Kumar Naveen, Chaudhary Rajiv

Archives of Thermodynamics

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2024

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Vol. 45, no. 4

27--35

EN

Using oxygenated alternative fuels in compression ignition (CI) engines is feasible for energy security problems and climate change. Alcohols are regarded as alternative fuels for compression ignition engines because of their excellent physicochemical features, emission, and combustion characteristics. Research on alcohols and their additions has progressed significantly in recent years. Several researchers have examined the combined effect of higher alcohol with diesel and their impact and challenged that concentrations of higher alcohol reduce harmful particulate emissions in CI engines. This paper mainly focused on the performance and emissions properties of higher alcohols like butanol and pentanol. Alcohol has a low energy content, typically affecting engine brake-specific fuel consumption (BSFC). Low-temperature combustion (LTC) in compression ignition engines can lower NOx and smoke emissions, and improve the efficiency of the engine. LTC is done by combining higher alcohol with increased exhaust gas recirculation (EGR) rate and retarded fuel injection timing. The higher alcohol, along with the oxygen in the fuel reduces exhaust fumes, improves the air/fuel mixture by providing a longer ignition delay (ID), and can replace the fossil fuel like diesel (partially or whole) to allow efficient and clean combustion in CI engines. Finally, several significant findings and comments are provided regarding potential avenues for experimental research and future development. According to thorough analysis, bio-alcohols are considered to be a substitute fuel for CI engines.

12

Simulation of torque variations in a diesel engine for light helicopters using PI control algorithms

Magryta Paweł, Barański Grzegorz

Applied Computer Science

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2024

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Vol. 20, no. 3

192--201

EN

This article presents the results of simulation research of a diesel engine for a light helicopter. The simulations were performed using the 1D software AVL Boost RT. The engine model includes elements such as cylinders, turbine, compressor, inlet and outlet valves, ambient environment definition, and fuel injection control strategy. The simulations aimed to evaluate the engine's response to step changes in the main rotor load, both increasing and decreasing power demands. Parameters analyzed included power deviation, torque, engine rotational speed, and stabilization time of the main rotor rotational speed. All tests were conducted using a single set of PI controller settings. The results demonstrate that these parameters are dependent on the magnitude of the step change in the main rotor load demand. The study compares the maximum engine rotational speed deviation from the nominal value for both increasing and decreasing main rotor load demands. The findings indicate that using PI regulator to control rotational speed in the diesel engine in a light helicopter significantly depends on the change in the load torque on the rotor.

13

Research on the Use of Multifrequency Excitations for Energy Harvesting in a Combustion Engine

Caban Jacek, Stączek Paweł, Wolszczak Piotr, Nowak Radosław, Karczmarzyk Stanisław

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 5

400--412

EN

Research conducted around the world shows that energy harvesting (EH) systems can be used in modern vehicles powered by combustion, hybrid or electric engines. The efficiency of modern combustion engines is about 40%, the rest of the energy is lost and can be recovered to some extent. Therefore, the search is ongoing for systems that will use this part of the energy to power specific systems or micro-sensors installed in the vehicle. The article presents the possibilities of energy recovery from such vehicle systems as: energy recovered during braking, damping energy in the vehicle suspension, energy recovery from the exhaust system of an internal combustion engine and energy from the vibrations of the internal combustion engine. Based on the analysis of the literature on the presented research of various scientific centers and the author's experiment, it can be concluded that there is a huge potential for obtaining thermal energy from the engine exhaust system and the vehicle suspension system. A field that has not been explored much, but according to the authors also has energy potential, is energy recovery from the combustion engine suspension system in the vehicle's engine compartment. Preliminary research shows the possibility of mounting the energy recovery system in the engine compartment and the potential possibility of obtaining electricity in certain operating states of the combustion engine.

14

Energy Consumption and Driving Parameter Analysis in an 18-Meter Long Urban Bus with Compression Ignition Engine

Grabowski Łukasz

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 8

16--29

EN

Urban buses equipped with diesel engines are still in use and currently account for more than 70% of all urban buses in use worldwide. This article discusses the results of the one-year research on the energy consumption by urban buses in Poland. The research object was a Mercedes Conecto. The analyses were carried out on an annual and monthly. The energy consumption was evaluated from the calculations of 284 days of operation. The average vehicle speed and average energy consumption were calculated as 16.05 km/h and 19.78 MJ/km, respectively. The distributions of energy consumption and average speed are plotted on the histograms. The next step was to determine the dependence of energy consumption on the daily distance covered, ambient temperature, and average speed. It was shown that an increase in average speed by 1 km/h results in a reduction of 0.65 MJ/km in fuel energy consumption, and an increase in ambient temperature results in a reduction of 0.06 MJ/km. In addition, the study shows a daily distance range from 210 to 220 km with the highest specific energy consumption of more than 21 MJ/km. The research results can be useful for improving the energy efficiency of public transport modes.

15

Analysis of the Influence of Fuel Dose on the Electrical Parameters of the Starting Process of a Single-Cylinder Diesel Engine

Caban Jacek, Seńko Jarosław, Słowik Tomasz, Dowkontt Szymon, Górnicka Dorota

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 4

55--65

EN

The start-up is a transient state of operation of an internal combustion engine during which many negative phenomena occur that affect the technical condition of the engine, its electrical equipment and the natural environment. The start-up process of an internal combustion engine is influenced by many factors, such as: technical condition of the starting system, technical condition of the engine, battery charge level, lubricant properties, engine standstill time, engine temperature, etc. Mechanical energy is required to start the engine, supplied by an electric starter by drives the engine’s crankshaft. Knowledge about the operating parameters of the electric starter during the start-up process is important not only for the user of the engine (vehicle driver), but above all for designers of modern combustion engine starting systems and service personnel. The paper presents the results of experimental tests of electrical parameters of the single-cylinder diesel engine start-up process at variable fuel injection parameters under ambient temperature conditions.

16

Optical-graphic studies of hydrogen additives’ effects on diesel fuel atomization parameters

Shalapko Denys

Transport Problems

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2023

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T. 18, z. 4

135--146

EN

This paper considers a promising method of enhancing the effectiveness of diesel engines. This method uses the addition of hydrogen in a small amount (up to 2% by mass). The hydrogen additive is added to the high-pressure fuel line before the injector. Based on the experimental findings, a reduction in the engine’s specific fuel consumption of up to 3% was achieved in comparison to the baseline configuration. A research study was conducted at the Admiral Makarov National University of Shipbuilding using a newly established experimental setup to assess the impact of hydrogen additives on primary fuel delivery, spray characteristics, and overall engine performance. Among the experiments conducted, one investigated fuel atomization parameters, focusing on how the presence of hydrogen in the fuel influenced the fuel jet’s characteristics. A high-speed camera with a high resolution was used to record the optical-graphic study to isolate and extract individual shots of the torch’s expansion, thus obtaining images devoid of ignition and flickering. After conducting image processing and constructing jet models, along with subsequent analysis, it becomes apparent that the addition of hydrogen to the primary fuel results in an enhancement of spray quality. The torch volume expanded by approximately 10% to 15%, while the jet length diminished by approximately 8% to 10%. Consequently, the average diameter of the atomized fuel droplets decreases by up to 10%, with the extent of reduction contingent upon the initial parameters and configurations.

17

High quality multi-zone and 3d CFD model of combustion in marine diesel engine cylinder

Cuper-Przybylska Dominika, Nguyen Van Nhanh, Cao Dao Nam, Kowalski Jerzy

Polish Maritime Research

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2023

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nr 2

61--67

EN

The paper presents a 3D model of the processes taking place in the cylinder of a large 4-stroke marine engine. The model is based on CFD calculations performed on the moving mesh. The modelling range includes the full duty cycle (720° crankshaft position) and the complete geometry of the cylinder with inlet and exhaust ducts. The input data, boundary conditions and validation data were obtained by direct measurements on the real object. Fuel injection characteristics were obtained by Mie scattering measurements in a fixed-volume chamber. The modelling results have been validated in terms of the pressure characteristics of the engine’s cylinder within the entire range of its loads. The mean error did not exceed 1.42% for the maximum combustion pressure and 1.13% for the MIP (Mean Indicated Pressure). The model was also positively validated in terms of the O2 and NOx content of the exhaust gas. The mean error in this case was 1.2% for NOx fractions in the exhaust gas and 0.4% for O2 fractions. The complete model data has been made available in the research data repository on an open access basis.

18

Research on the impact of various coating types on parts wear of certain injection pump elements

Bałon Paweł, Rejman Edward, Smusz Robert, Kiełbasa Bartłomiej

Mechanik

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2023

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R. 96, nr 1

44--47

EN

The geometric structure of mating surfaces has a crucial influence on the friction and resulting wear processes. This is particularly important in the case of injection pumps, where ensuring appropriate surface quality and tightness in a long-term operation process is extremely important in order to maintain nominal operating parameters. It is extremely important during variable pump operation conditions, start-up and shutdown, when there is a significant deterioration of cooperative conditions resulting from insufficient lubrication of the mating surfaces. The contact pressures on the mating surfaces are increasing and they are in contact with each, causing significant wear and high movement resistance. The technology of the application of special coatings is used in industrial scenarios for the deposition of thin layers to modify the surface layer in order to improve tribological properties, increase abrasive wear resistance, and improve the visual quality of the surface. The authors compared the current possibilities of the technique (ceramic coatings) with the commonly known methods for strengthening the cooperative surface (phosphating). As part of the work, several potentially applicable types of protective coatings were tested.

PL

Struktura geometryczna powierzchni współpracujących wywiera kluczowy wpływ na procesy tarcia i zużycia. Jest to istotne w przypadku pomp wtryskowych, w których zapewnienie odpowiedniej jakości powierzchni oraz szczelności w długotrwałym procesie eksploatacji jest niezwykle ważne dla utrzymania nominalnych parametrów pracy. Ma to ogromne znaczenie podczas zmiennych warunków pracy pompy, rozruchu i zatrzymania, gdy występuje znaczne pogorszenie warunków współpracy wynikające z niedostatecznego smarowania powierzchni współpracujących. Zwiększają się naciski kontaktowe na powierzchnie współpracujące, które stykają się ze sobą, powodując znaczne zużycie i duże opory ruchu. Jednym ze sposobów zmniejszenia zużycia współpracujących elementów jest nałożenie powłok. Technologia nakładania specjalnych powłok jest stosowana w warunkach przemysłowych do osadzania cienkich warstw w celu modyfikacji warstwy wierzchniej, aby poprawić właściwości tribologiczne, zwiększyć odporność na zużycie cierne i polepszyć wizualnie jakość powierzchni. Autorzy porównali obecne możliwości techniki (powłoki ceramiczne) z powszechnie stosowanymi metodami wzmacniania powierzchni współpracy (fosforanowanie). Przetestowano kilka możliwych do aplikacji rodzajów powłok ochronnych.

19

Analysis of potential improvements in the performance of solenoid injectors in diesel engines

Vrublevskyi Oleksandr, Wierzbicki Sławomir

Eksploatacja i Niezawodność

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2023

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Vol. 25, no. 3

art. no. 166493

EN

Efficient fuel injection and exhaust gas cleaning systems are needed to promote the development of high-performance internal combustion systems and decrease greenhouse gas emissions. Electronically controlled injection systems enable nearly unlimited control over system components whose operation is limited by the inertia of moving parts and other physical phenomena. In the present study, a novel technology for manufacturing magnetic cores was proposed to improve the performance of solenoid injectors in Diesel engines. The conducted simulations and experiments revealed that the developed technology can increase the speed of solenoid injectors. In the proposed solution, the fuel dose was split to effectively control the injection process and improve engine performance.

20

Preliminary tests of a Diesel engine powered by diesel and hydrogen

Longwic Rafał, Tatarynow Dawid, Kuszneruk Michał, Woźniak-Borawska Gracjana

Combustion Engines

|

2023

|

R. 62, nr 4

35--39

EN

This article discusses the possibilities of powering a commonly used diesel engine with renewable fuels. It analyses scientific studies that clearly indicate that the use of hydrogen is a potentially future-proof option due to its potential to reduce specific fuel consumption and improve performance and increase thermal efficiency. The research was carried out on a laboratory bench designed to test a diesel engine fueled by different fuels. A proprietary hydrogen injection system with dedicated control software was used. Hydrogen injection pressures of 0.15, 0.18, 0.20 MPa and hydrogen injector opening times of 2.5, 3.0, 3.5 ms, respectively, were set as control parameters. The rapidly varying engine operating parameters were recorded and the parameters calculated from them were analysed.