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EN
The BAT-CELL Bio-Ambient-Tests method is based on the assessment of the influence of the actual toxicity of various types of gas mixtures on living cells, taking into account the additive synergism. Work has been carried out on the application of the BAT-CELL method for testing engine exhaust gases. The application of computational fluid mechanics using Ansys Fluent made it possible to analyse the flow of engine exhaust gases through the aspiration system used, including analysis of shear stress values and their uniformity distribution on the bottom wall of the sampler containing cell culture on the bottom wall of the sampler. The appropriate flow rate of exhaust gases through the aspiration system and the shape of aspiration tubing for the sampler were selected in order to enable uniform contact of gas particles with the cell surface and not to damage them mechanically. The simulation results were verified in real-life tests and confirmed the theoretical assumptions.
EN
The article discusses the research results on the combustion of pyrolysis oil derived from the pyrolysis of HDPE plastics after its distillation. The tests were carried out in a constant-volume combustion chamber in conditions similar to those in a compression-ignition engine with a compression ratio of 17.5:1. The phases of premixed and diffusion combustion and the ignition lag were determined. Then, diesel fuel combustion tests were performed under similar pressure-temperature conditions. Comparative analysis was used to draw conclusions as follows: the percentage fraction of heat released from the premixed combustion phase to total heat for pyrolysis oil was nearly 22%, whereas this parameter is 15% for diesel fuel, the maximum combustion rate for the premixed combustion phase for pyrolysis oil was approximately 27% higher than the premixed combustion rate for diesel fuel, the ignition lag for pyrolysis oil was slightly longer compared to that for diesel fuel. The presented parameters have a significant impact on both the development of combustion and the thermal efficiency of the internal combustion engine. Summing up, one can conclude, that pyrolysis oil can be applied as a substitute for diesel fuel both as a single fuel or blend component with it.
EN
The worldwide aim of reducing environmental impact from internal combustion engines bring more and more stringent emission regulations. In 2017 by EU has been adopted new harmonized test procedure called WLTP. In general terms this test was designed for determining the levels of harmful emissions and fuel consumption of traditional and hybrid cars. This procedure contains specific driving scenarios which representing real-life driving patterns. Test cycles contain vehicle velocity versus time profiles and directly in powertrain analysis on the test benches cannot be used. In order to back calculate drive cycles to engine rpm versus torque profiles a simple longitudinal vehicle dynamics method was used in this paper. Moreover, in order to determine most representative engine operation points during WLTP a density based grid clustering method was implemented. The experimental part of the study focuses on the comparative evaluation of the effect of various diesel to LPG substitution ratios (0% LPG, 10% LPG, 20% LPG and 30% LPG) on combustion and emission characteristics of dual-fuel diesel engine.
EN
A piston-rings-cylinder (PRC) assembly determines the blowby, engine oil consumption, and friction and wear processes accompanying the system's operation. Thus, it is crucial for the whole IC engine efficiency and lifetime. A lot of research effort is put into increasing the performance of this complex and highly dynamic system. Advanced, comprehensive models play an important role in understanding and improving the PRC system. In the presented work, the effect of load on the operation of the ring pack of an automotive gasoline engine is analyzed. A comprehensive model that covers the gas flow through the crevices of the PRC system, ring displacements in the groove, and ring lubrication was used for this analysis. The results of the simulations show that the local thickness of the oil film, especially near the piston top dead center is compared to the height of the combined surface roughness of a cylinder liner and piston rings, and friction-related asperity contact strongly increases as the engine load increases. The simulations also show that the engine load affects the axial displacements of the rings in the grooves but practically does not affect the thickness of the oil film left by the ring pack on the cylinder liner.
EN
This paper examines the effect of an external preheating system for an internal combustion engine on fuel consumption, CO2 emissions, and cabin temperature of a Euro4 vehicle. A 1 kW electric system powered by 220 V was installed in series in the cooling system of a vehicle with a compression-ignition engine of 2.5 dm3 capacity. The tests were carried out in simulated urban driving conditions (distance of 4.2 km), extra-urban driving conditions (distance of 17 km), and during idling at cold-start temperatures ranging from -10oC to 2oC. Preheating the engine under simulated city conditions reduces fuel consumption by 2.64 dm3/100 km and increases the supply air temperature immediately after engine start-up. Due to the preheater being powered from an external power grid, the cost per trip and total CO2 emissions are increased. Assuming renewable energy sources, CO2 emissions would be reduced the most for the stationary tests after engine preheating. In contrast, emissions would be reduced the least for extra-urban driving.
EN
Nanomaterials are a new group that has quickly found a wide range of applications in medicine, cosmetology, the food, weapons or automotive industry. They are also used as a fuel additive. This paper reviews the literature and assesses the current state of knowledge regarding the use of nanoparticles in automotive engine fuels. The results obtained so far are presented and further research directions in this field are identified.
EN
The article presents the results of operational tests of engine oil, including the observation of changes in the values of selected physicochemical parameters of oil in subsequent operation cycles, in accordance with the service life specified by the vehicle manufacturer. Preliminary analysis of defined indicators characterizing the condition of engine oil were performed in terms of their suitability for the ongoing monitoring of the technical condition of the engine. On the basis of the values of selected indicators of fresh oil recorded in the course of operational tests and during replacement, one indicator was selected, the kinematic viscosity at 100°C, for which an unambiguous trend of changes was observed during the tests. The last stage was to verify the hypothesis about the correlation between the observed changes in the value of the indicator and the mileage of the engine-vehicle.
EN
The article presents the results of emission tests and vehicle operation indicators fueled with diesel oil. The tests were carried out for a passenger vehicle equipped with a diesel engine meeting Euro 3 emissions standard, moving in urban traffic. The measurements were carried out using modern PEMS (Portable Emission Measurement System) enabling the emission of gaseous components from exhaust systems of the tested object. On the basis of the conducted tests, the load characteristics were determined using the torque values obtained along with the engine speeds. The measurement route included two cycles: urban driving and fast acceleration. The aim of the study was to assess the impact of modifications to the control maps on CO, CO2, PM and NOx exhaust gas emissions under real operating conditions.
EN
The article presents a diagnostic and reliability model of an internal combustion engine that allows to assess the reliability status of the engine’s systems for a two-state model of operation and maintenance: functional - failed. The proposed diagnostic model is a qualitative-quantitative probabilistic model combining the reliability states of the engine systems with the values of the vibroacoustic diagnostic signal parameters. The conducted diagnostic and reliability experiments and simulation tests showed that based on the developed diagnostic and reliability model, it is possible to determine the reliability states of the engine.
10
Content available The use of glycerine as motor fuel
EN
Glycerine as waste from production accounts for about 10% of the obtained amount of biodiesel. It is a very attractive substance for the industry, however, currently the industry is not able to absorb such a large amount of glycerine produced during the production of fuel. Therefore, one should look for other ways of disposing of glycerol with simultaneous benefit in the form of energy yield or useful products / semi-finished products. The development of glycerine is necessary due to the continuous development of the biofuel market. In the near future, surplus glycerine may pose serious problems in the growth of biodiesel production. The publication presents the results of scientific research on the use of liquid technical glycerine and its processing products in the gasification process, as engine fuel.
EN
The modification of the downsizing trend of internal combustion engines towards rightsizing is a new challenge for constructors. The change in the displacement volume of internal combustion engines accompanying the rightsizing idea may in fact mean a reduction or increase of the defining swept volume change factors and thus may affect the change in the operating characteristics as a result of changes in combustion process parameters - a research problem described in this publication. Incidents of changes in the displacement volume were considered along with the change of the compression space and at the change of the geometric degree of compression. The new form of the mathematical dependence describing the efficiency of the thermodynamic cycle makes it possible to evaluate the operation indicators of the internal combustion engine along with the implementation of the rightsizing idea. The work demonstrated the invariance of cycle efficiency with different forms of rightsizing.
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