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The analysis of the overall performance of the engine powered by selected gaseous fuels has been presented in this paper. Primary objective of the research was to determine the influence of fuel type on efficiency of energy conversion in the tested engine. The scope of the research featured: application low-carbon fuels, use of DME as a renewable fuel in blends with LPG. The use of low-carbon gaseous fuels gives the opportunity to reduce exhaust gases emissions. The basic assumption in the presented research was the use of gaseous fuels, for which the main component is methane. The main problem taken into consideration was excessive duration of the combustion process, which is one of the causes of the engine overall efficiency reduction when running on gaseous fuels. This issue becomes even more important due to the lower heating value of natural gas (methane) when compared to conventional fuels.

Paper describes analysis of the design process of modern automotive LPG and CNG containers. Over decade experience in the field of both computer based analysis as well as in the real conditions testing has been collected and presented in the paper. Authors present the potentials of modern FEM methodologies in the optimization and production of lightweight steel containers. It has been proved that the most sophisticated numerical analysis have to be followed by the construction verification, particularly considering direct exposure to fire. Bonfire test have become obligatory for both liquid and compressed gases containers. Properly chosen fire protection system, together with the adequate level of quality of materials applied for its production together with proper directing of the gas flowing out from safety devices are the essential factors defining gas containers fire safety.

A study on the overall performance of an engine powered with hydrogen-enriched NG at stoichiometric condition, for different hydrogen shares have been described in this paper. The research has been carried on a General Motors Company X16SZR 4-cylinder, 4-stroke 1600 cm3 engine. Engine dynamometer tests were complemented with mathematical model calculations. Tested engine has been equipped with an aftermarket CNG feeding system where fuel is being injected into intake manifold simultaneously under low overpressure. Research program provided analysis for fuel blends with variable methane/hydrogen volume proportion (%): 100/0, 95/5, 90/10, 85/15, 80/20, 70/30, 60/40 and 50/50. Ignition timing and all other strategies, excluding EGR, remained unvaried. Testing procedure provided three different steady-state engine operation points for each of 8 different fuels: idle, high speed without load and full power at speeds in range of 1500-3500 rpm.

Paper presents the general assumptions for an gaseous fuels injector rail diagnosis and calibration with the application vibroacoustic methods, considerably different from used today methodology which typically base on measurements of mechanical dislocation of piston/nozzle, and injector flow rates has been described in the paper. Flow rates, as well as injector actuator stroke measurements are time-consuming and require the use of complex systems. This is what generally disables the methods currently in use from their integration in the continuous control system, especially into OBD. Methodology presented in the paper, based on simultaneous measurements of injector opening time and its vibration, allows an enhanced accuracy of the calibration and diagnosis process. It also shortens the time of calibration since it does not require invasion into mechanical system of injector rail and allows a quick and efficient assessment of its proper operation.

The potential of hydrogen-methane blends application in dual-fuel SI engines in their overall performance improvement has been evaluated and described in this paper. The 1.6 litre engine alternatively fed with petrol, CNG and with methane-hydrogen blends has been tested. Generated outboard methane-hydrogen blends, used in the research programme featured following hydrogen-CNG ratios: 5%, 10%, 15%, 20% and 30%. For selected engine operating conditions, a complete set of data defining engine overall performance, such as power output, in-cylinder pressure variation, manifold pressure and finally mass fuel consumption has been acquired. On the basis of registered data for all the tested fuels, with the use of mathematical model describing the exhaust gases formation it was possible to estimate the NO, CO and CO2 emission levels.

The availability of gaseous fuels such as natural gas and propane butane mixtures has led to worldwide popularity of internal combustion engines running dual fuel or alternatively gas powered. These gaseous fuels are known as fuels more resistant to knocking than conventional liquid fuels and as less ones pollutant. Their better mixing with air is also well recognized. There are some works published on the use of gaseous fuels, but the problem of the combustion noise, as a very important source of information regarding the combusted fuel, is not receiving much attention. Combustion noise occurs in two forms, direct and indirect. It is transmitted throughout the engine block as a vibration at a different spectrum of frequencies. In this study an attempt is made to relate the combustion noise to the operating parameters for LPG, CNG and Hydrogen enriched CNG powered engine as compared to petrol fueled engine.

The main goal of this project was the identification of the influence of gas injector location on air - fuel mixture formation. Stand tests and roller bench tests results for an alternatively gas powered engines were presented in the paper. Important influence of gas injection direction on mixture formation and as a result on emission levels has been proved. A detailed analysis of a proper aftermarket gas feeding system application procedure was described.

Influence of piston skirt clearance on engine noise has been presented in this paper. Traces of forces producing engine block vibrations, i.e. gas force, and piston slap force were estimated and verified with real sampled data. An engine block vibration signal decomposition was also carried on, what enabled the identification of the influence of piston clearance on wavelet factor values C(a,b). It has been proved that increasing piston skirt clearance, delays the response of engine body on piston slap.

The availability of gaseous fuels like natural gas and propane butane mixtures has lead to worldwide popularity of internal combustion engines running dual fuel or alternatively gas powered. These gaseous fuels are known as fuels more resistant to knocking than conventional liquid fuels and as ones less pollutant, their better mixing with air is also well recognized. There have been many published works on the use of gaseous fuels but actually the problem of the combustion noise, as a very important source of acoustic discomfort is not receiving attention. Combustion noise occurs in two forms, direct and indirect. It is transmitted throughout the engine block as a vibration at a different spectrum of frequencies. In this study an attempt is made to relate the combustion noise to the operating parameters for LPG powered engine as compared to petrol fueled engine.