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EN
The article discusses methods for determining top dead center, based on the analysis of pressure diagrams of a marine engine. The advantages and disadvantages of different methods are shown. Diagnostics of marine engines during operation and the selection of optimal operating conditions is based on the analysis of gas pressure diagrams, as well as fuel supply and gas distribution diagrams. As a result of the analysis of the pressure diagrams, the indicator engine power is calculated, which is further used in the management of engine operation modes, in the calculation of specific indicators, as well as in the calculation of energy efficiency coefficients of marine vessels according to International Maritime Organization recommendations. The influence of the accuracy of determining the position of the top dead center on the calculation of the mean indicated pressure and indicator power is shown. The authors considered a method for determining top dead center, based on the solution of the equation P’= 0, which provides the required accuracy in calculating the mean indicated pressure and indicator power of the engine during operation. It is shown that the method can be applicable in marine engine working process monitoring systems as an alternative to hardware methods for determining the top dead center.
EN
Vibration energy harvesting systems are using real ambient sources of vibration excitation. In our paper, we study the dynamical voltage response of the piezoelectric vibrational energy harvesting system (PVEHs) with a mechanical resonator possessing an amplitude limiter. The PVEHs consist of the cantilever beam with a piezoelectric patch. The proposed system was subjected to the inertial excitation from the engine suspension. Impacts of the beam resonator are useful to increase of system’s frequency transition band. The suitable simulations of the resonator and piezoelectric transducer are performed by using measured signal from the engine suspension. Voltage outputs of linear (without amplitude limiter) and nonlinear harvesters were compared indicating better efficiency of the nonlinear design.
EN
The paper presents the methodology for designing the injection shaft drive for diesel engines with 2,3,4,6 and 8 cylinders as well as power from 2.5 to 52 kW per cylinder using the FEM method and experimental research. The pump is the original solution of the authors. The shaft is a basic part of the pump with a complex structure. In order to assess the state of stress in the shaft, the FEM analytical method was used and experimental tests were carried out, subjecting the shaft to torsional moment resulting from the transmitted power. Experimental studies confirmed the results of numerical calculations and the correctness of the adopted solution. The destructive tests were carried out to assess the maximum load capacity of the shaft, loading it with an increasing torque until visible plastic deformations occurred. This condition appeared at twice the moment (Ms = 602 Nm) in relation to the maximum predicted moment in operation (extreme operating conditions of the pump shaft). The theoretical studies confirmed very significant stress concentration (αk coefficient at the level of 2.63 or even 4.7), which may be the cause of fatigue cracks. It also determines the strength of the shaft and its torsional stiffness, which influences the proper functioning of the pump and ensures adequate fuel injection phases.
EN
In this study, an experiment was conducted to examine the AVL research diesel engine using two kinds of waterdiesel (W-D) fuel microemulsions. These W-D mixtures contained 3.5 and 7.0% by volume (%, v/v) of distilled water dispersed in regular diesel fuel meeting the requirements of the EN590 standard. The engine was tested under the conditions of low, moderate and higher loads. This research was focused on the emission characteristics of nitrogen dioxide (NO2 ) and nitrogen monoxide (NO). Cumulative emission of NOx was also analyzed before being further discussed. The obtained results of this study showed that the addition of distilled water to the regular diesel fuel has a minor effect on the variation of the nitrogen oxides emission. It was confirmed that NO is the main component of NOx detected in the exhaust stream of the AVL engine fuelled with all tested fuels. It proves that the thermal mechanism of the nitrogen oxides formation was dominant in the combustion process. Moreover, it was found that the addition of water dispersed as microemulsion in diesel fuel had a minor effect on the reduction of the NOx emission.
EN
The paper presents the research results of the AVL diesel engine powered with microemulsion fuels. In particular the emission of soot particles from the engine operated under stationary conditions was investigated. The necessary tests were carried out for two microemulsions containing 3.5 and 7% by volume of distilled water dispersed in diesel fuel with necessary surfactants/cosurfactants, i.e. Crillet-6/Span-20. Both tested microemulsions contained similar water micelles size distribution with average dimension of 18 nm. The results of the investigation confirmed that the combustion of tested water – fuel microemulsion in the AVL research engine reduces the emission of soot particles even by 50% in comparison with the diesel fuel.
PL
Wdrożenie w silnikach Diesla lokomotyw spalinowych systemów dwupaliwowych – olej napędowy / gaz ziemny, prowadzi do obniżenia emisji substancji szkodliwych w spalinach oraz oszczędności w związku z konkurencyjnymi cenami gazu ziemnego. Przedstawiono opis zespołów i urządzeń systemu dwupaliwowego wdrożonego na lokomotywie spalinowej serii S200 wraz z rysunkami ich zabudowy w pojeżdzie. Omówiono zagadnienia dotyczące układu sterowania, prób i badań lokomotywy, certyfikacji, infrastruktury tankowania gazu. Zaprezentowano wyniki badań stacjonarnych i ruchowych lokomotywy oraz uzyskane efekty.
EN
With 70% of all locomotives still being powered by diesel and most of the locomotives being older than 30 years, the railway industry must urgently seek environmentally friendlier and economically more attractive alternatives to diesel fuel. Dual-fuel systems once installed on diesel locomotives, allow substituting most diesel fuel with much cheaper and cleaner gas fuels – biogas, natural gas, and syngas – without the necessity for large capital investments. This article describes a case of dual-fuel conversion of a S200/CHME3 series diesel locomotive, introducing to the system specifics, certification procedure, gas refueling infrastructure, as well as outlining the main economic and technical results. The article concludes by outlining the dual-fuel perspectives in the Polish railway industry and estimates the economic and ecological benefits its implementation can bring.
EN
For internal combustion engines, many faults relating to the combustion process can occur, which affect the engine technical condition, its electrical equipment, the natural environment, etc. This article presents the results of the influence of the regulatory factor, which was the fuel dose (3 dose values), on selected parameters of the start-up process at constant settings of other control parameters (fuel injection advance angle and injection pressure). The tests of the start-up process were carried out on a fourstroke single-cylinder diesel engine. In this study, the results of the following electrical start-up parameters were analyzed: the maximum current consumed by the starter, difference of voltages on the battery before and after the start-up, voltage drop on the battery at the beginning of the start-up, average power of the starter, starter operation time, and the maximum pressure value in the first combustion cycle.
EN
The paper considers the issue of thermo-chemical recovery of engine’s waste heat and its further use for steam conversion of the associated gas for oil and gas floating units. The characteristics of the associated gas are presented, and problems of its application in dual-fuel medium-speed internal combustion engines are discussed. Various variants of combined diesel-gas turbine power plant with thermo-chemical heat recovery are analyzed. The heat of the gas turbine engine exhaust gas is utilized in a thermo-chemical reactor and a steam generator. The engines operate on synthesis gas, which is obtained as a result of steam conversion of the associated gas. Criteria for evaluating the effectiveness of the developed schemes are proposed. The results of mathematical modeling of processes in a 14.1 MW diesel-gas turbine power plant with waste heat recovery are presented. The effect of the steam/associated gas ratio on the efficiency criteria is analyzed. The obtained results indicate relatively high effectiveness of the scheme with separate high and low pressure thermo-chemical reactors for producing fuel gas for both gas turbine and internal combustion engines. The calculated efficiency of such a power plant for considered input parameters is 45.6%.
PL
„W jaki sposób mogę efektywniej korzystać z moich maszyn?” – to podstawowe pytanie nurtujące wszystkich właścicieli oraz użytkowników maszyn drogowych.
10
Content available remote Research and FEM analysis of the injection pump shaft for diesel engines
EN
The paper presents the methodology for designing the drive shaft of the injection pump for diesel engines with cylinder numbers of 2, 3, 4, 6 and power from 2,5 kW to 52 kW per cylinder using the finite element method (FEM) and experimental research. The pump is the original solution of the authors. The shaft is the basic part of the pump with a complex structure. In order to assess the state of stress in the shaft, the analytical FEM was used and experimental tests were carried out, subjecting the shaft to twisting with the design torque resulting from the transferred power. Experimental research confirmed the results of numerical calculations and the correctness of the adopted solution. In order to evaluate the maximum load capacity of the shaft, destructive tests were carried out, charging it with increasing torque until visible plastic deformations occurred. This condition occurred at a time twice as high as the maximum anticipated moment in operation.
PL
W pracy przedstawiono metodykę projektowania wału napędowego pompy wtryskowej do silników wysokoprężnych o liczbie cylindrów 2, 3, 4 i 6 oraz mocy od 7,5 do 57 kW na cylinder, z wykorzystaniem metody elementów skończonych (MES) i badań eksperymentalnych. Pompa jest oryginalnym rozwiązaniem autorów. Wał jest podstawową częścią pompy o złożonej strukturze. Do oceny stanu naprężenia w wale zastosowano metodę analityczną MES oraz przeprowadzono badania eksperymentalne, poddając wał skręcaniu momentem obliczeniowym wynikającym z przenoszonej mocy. Badania eksperymentalne potwierdziły wyniki obliczeń numerycznych i poprawność przyjętego rozwiązania. Aby ocenić maksymalną nośność wału, przeprowadzono badania niszczące, obciążając wał rosnącym momentem skręcającym do wystąpienia widocznych odkształceń plastycznych. Taki stan pojawił się przy momencie dwukrotnie większym w stosunku do maksymalnego momentu przewidywanego w eksploatacji.
11
Content available remote A review of the behavior of fuel drops in a fuel spray in the context of biofuels
EN
In addition to gasoline and diesel fuel, the biofuels HVO and FAME have been taken into wide use during the last decades. The properties of gasoline and diesel fuel and their effect on the combustion process have been studied for a long time, but studies on HVO and FAME are still are very much work-in-progress. Existing studies show that the use of biodiesels reduces the level of several exhaust gas emissions (like soot) in engine exhaust gases. At the same time, the reasons for the reduction of emission compounds remain unclear. The motivation behind determining drop size and behavior is to aid assessment of the quality of the air-fuel mixture with a view to explaining the reduction in soot emission when biodiesels are used. The aim of this review paper is to provide an overview of the behavior of fuel drops and their size in fuel injectors when using different biofuels by giving a theoretical background based on literature, on the basis of which the calculations give an opportunity to evaluate experimental results of the behavior of different biofuels in the fuel spray. This study compares four different fuel types according to the WAVE-RT model. In addition, the collision mechanisms of drops (reflexive and stretching separation) are presented and these shall be compared for the fuel types. The results show that during the use of biofuels, the drop size is somewhat larger compared to diesel fuel.
12
Content available remote Conversion of diesel engine to alternative bio-alcohol fuel
EN
Research has been carried out on feasibility of using biomethanol as a fuel in diesel engines converted for work on spirits, compared to usage of diesel fuel of petroleum origin. For realization of these tasks at Department of Automobile Transport in IFNTNG was converted for work on methanol automobile diesel engine of model XI7DTL OPEL. To convert the diesel engine to methanol compression strength of the engine was reduced to 14.1 by installing of additional gaskets under the head of cylinder block, an original microprocessor DIS ignition system of own design was installed, and engine management system was optimized. Experimental dependences of effective power and specific fuel consumption on the crankshaft rotational speed for the original diesel engine and converted for methanol diesel engine have been investigated. It is established that transferring diesel engine for work on methanol it is possible to achieve power indexes of original one. Analysis of exhaust gases during transferring of diesel engine to work on methanol shows that in all modes of engine there is a significant reduction in emissions of nitrogen oxides and carbon monoxide.
EN
The objective of the present work is to find out the viable substitute fuel for diesel and control of pollutants from compression ignition engines. Therefore, in this present investigation an attempt has been made to study the effect of 20% proportion of five different biodiesel diesel blend in diesel engine. The 20% proportion of biodiesel such as Jatropha, Pongamia, Mahua, Annona and Nerium and 80% of diesel and it is denoted as J20, P20, M20, A20 and N20 are used in the present investigation. The experimental results showed that the brake thermal efficiency of the different biodiesel blend is slightly lower when compared to neat diesel fuel. However, N20 blend, have shown improvement in performance and reduction in exhaust emissions than that of other biodiesel diesel blends. From, the experimental work, it is found that biodiesel can be used up to 20% and 80% of diesel engine without any major modification. The conducted experiments were conducted on a four cylinder four stroke DI and turbo charged diesel engine using biodiesel blends of waste oil, rapeseed oil, and corn oil with normal diesel. The peak cylinder pressure of the engine running with bio diesel was slightly higher than that of diesel. The experiments were conducted on a four cylinder four stroke diesel engine using bio diesel made from corn oil.
EN
The aim of the study was to compare the impact of dynamic viscosity of two biofuels. One was a mixture of 50% (m / m) SBME and 50% (m / m) RME of own production. The mixture was conventionally called FAME. The second biofuel was commercial RME from a gas station. Dynamic viscosity as a function of temperature from -20 to 50oC was tested. The main device used at the measuring stand was ReolabQC rheometer manufactured by a German Anton Paar GmbH company. Dynamic viscosity especially grew rapidly after cooling biofuels to temperatures below -5°C. Dynamic viscosity FAME biofuels produced from pure vegetable oil (soybean oil and rapeseed oil) in a temperature range of 50 to -20°C has a value of c.a. 9 to 53[mPa∙s]. Dynamic viscosity of Biofuel FAME produced from mixtures of vegetable oils it was on average lower by about 1 to 8 [mPa∙s] of RME shopping from a gas station.
EN
The aim of the study was to determine the impact of the fish frying process on the distillation properties of FAME and its mixtures with diesel fuel. The fish was fried at 160°C for 2 hours. Frying one serving lasted 6 minutes. The frying oil was a mixture of 50% (v/v) rapeseed oil and 50% (v/v) sunflower oil. The study showed that FAME biodiesel made from unused (pure) oil has similar distillation properties. The largest differences were observed for distillation temperatures of 85% and 100% and the final temperature of the distillation process. This may indicate a slightly lower purity of FAME produced from used cooking oil. In such a biofuel there may be more less volatile mono- and diglycerides or other chemicals that, e.g. after frying, remain in oil. It must be said, however, that they are not solid particles because they have been separated from the oil by filtration.
EN
The paper presents algorithms for marine diesel engines’ working process monitoring designed by analyzing data obtained with IMES pressure sensors. Main features and properties of IMES sensors, used for 2- and 4-stroke modern marine diesel engines, are presented here. The pressure-time diagrams were taken as a basis for creating algorithms for marine diesel engines’ working process monitoring. The task of preliminary calculation of top dead center position (TDC) of a cylinder was solved using polytropic compression equation. TDC position was calculated using the equation P' = 0. Then algorithm for calculating the average indicator pressure and the indicator power of the cylinder has been determined. The CFD methods show how indicator valve channel influences the results of marine diesel engines’ working process monitoring. With the example of compression curves in a cylinder, it’s shown amplitude and phase distortions introduced into pressure measurements by the indicator valve channel. Such research work is important and actual in time due to the use of marine diesel portable performance analysis systems.
17
Content available Turbocharging the aircraft two-stroke diesel engine
EN
The power and efficiency of a two-stroke engine strongly depends on the efficiency of the scavenging process which consists in removing the rest of the exhaust gases from the cylinder and filling it with a fresh charge. The quality of the charge exchange process is significantly influenced by the construction of the intake system. The paper presents a zero-dimensional model of the aircraft two-stroke opposed-piston diesel engine with two variants of the intake system: with a mechanical compressor and a turbocharger connected in series with a mechanical compressor. Simulation studies of the developed cases were carried out in the AVL BOOST software. For the defined engine operating points, its performance was compared for different designs of the intake system. It was confirmed that the use of a turbocharger with a mechanical compressor extends the range of operating at high altitudes.
EN
To avoid the negative effects of increasing the amount of RME in the diesel fuel (to 10%), three different additive packages were used: stabilising, cleaning, and increasing the cetane number with different concentrations. The tests were carried out using a 4-cylinder, turbocharged 1.9 TDI engine from VW. The tests were carried out for 4 fuels (comparative fuel with a content of 7% RME and 3 test fuels with a content of 10% RME, differing in the content of the additive package. It was found that each of the 3 additive packages used does not have a significant impact on fuel consumption. However, a different effect of the tested additives on the composition of exhaust gases was observed. The first package had a slight effect on reducing the NOx concentration in the exhaust, but only for small engine loads. On the other hand, the second additive pack worked more effectively only at higher engine loads (in relation to the reduction of NOx concentration in the exhaust gases). In the third packet, the amount of the cetane additive was doubled (compared to the second packet). Then, the reduction in the NOx concentration in the exhaust gas by 3-8% was obtained with reference to the comparative fuel.
EN
The measurement of combustion pressure relies on connecting a pressure sensor to a four-stroke marine engine cylinder by a channel led out from the engine cylinder. The geometry of the channel distorts the results of combustion pressure measurements. The purpose of the work is to create a model of combustion processes in engine cylinders. The model uses a mathematical description of the indicator channel on one of the engine cylinders. The input data to the model and the data necessary for its verification came from the direct measurements on the research facility. The test object was a four-stroke Sulzer 3AL25/30 engine loaded by an electric power generator. During calculations, different diameters and lengths of measurement channel were simulated. The obtained results allowed to formulate the conclusion that the geometry of the measurement channel has a significant impact on the measurement results. The increase of the length of the measuring channel as well as the diameter of the channel causes disturbances in the measurement of the maximum pressure.
EN
This publication is the next part of the article “The influence of cetane-detergent additives in diesel fuel increased to 10% of RME content on energy parameters and exhaust gas composition of a diesel engine”. The cause-effect analysis of the phenomena related to the impact of 3 additive packages used in diesel oil with RME content increased to 10% (compare to standard diesel fuel with 7% of RME) was described. The basis for the analysis of the impact of the tested fuels on energy parameters and composition of exhaust gases were the parameters of indicator diagrams and heat release parameters. It was found that the first set of additives affects the delay of auto-ignition of fuel and kinetic fuel combustion speed only at low engine loads. In this range of engine operation the NOx concentration in the exhaust gas is low and besides there is a large of EGR. The second additive package was operated at high engine loads but its impact on the lower self-ignition delay was quantitatively small. Therefore, in the third packet of additives, the amount of additives used in the second packet was doubled. Then a satisfactory shortening of the self-ignition delay and reduction of the max rate of kinematic heat release was achieved as a reason of a reduction of NOx concentration in the exhaust up to 8% (compared to the reference fuel).
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