Search Results

The paper presents a new method for assessment of combustion process correctness taking place in CI engines, based on the expanded vibroacoustic signal analysis. The method uses chosen non-linear, spectrum and time-frequency analyses of the signal. Diagnostics of the correctness of the above main engine process and misfire detection for engines at exploitation conditions with the use of the various methods of the accompanying processes analysis was the aim of the presented analyses. Possibility of the method application to combustion process assessment of the CI engines was verified, algorithms of misfire detection for the each method are described, quantity point estimators of processes and conditions of the OBD diagnostics realization were obtained, methodology of the measurement process, limits of the methods use and their diagnostic accuracy in the point of view of the combustion OBD III engine monitor design are also presented.

The paper describes the problem of the combustion process diagnostics dedicated for CI engines with direct injection of HDV vehicles in the aspect of misfire detection monitor application for OBD and EOBD systems. The monitor is based on the vibroacoustic signal utilization. Because of that, frequency method and the method of time-frequency parameterization map a(t,f) of vibration accelerations generated by combustion engine were used. The above article is directed to get a diagnostic monitor that would detect faults and incorrect runs in the combustion process (including also its lack) in the real time with the help of vibration accelerations estimators. Point estimators of the process and research stages and conditions are presented. The signal analyses and limits of a method use, criteria of the process qualification and its accuracy were also write down.

The Institute of Combustion Engines and Transport has developed a concept of fuelling diesel engines with an improved mechanism of spray. To facilitate the spray, and consequently the combustion process, air or exhaust gas was dissolved in diesel oil. The gases mixed with diesel oil formed a solution, which induced non-equilibrium state owing to its effervescence. As a result, the gaseous phase spontaneously released from the solution throughout the whole volume. The paper presents the results of observations and measurements of the fuel injection into the open chamber recorded with AVL 513D Engine Video System. The injection process has been realized with a common rail system, where the conventional mechanism of fuel atomization has been enhanced by the presence of gas in the fuel. The solution of gas and fuel was considered separately as non-saturated, saturated and supersaturated (in the last case, some amount of gas remained undissolved in the fuel).