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The aim of the publication was to present the effect of the full power characteristics of the internal combustion engine and the traction characteristics of the vehicle on its safety when moving in urban traffic. The movement of the vehicle in the city was characterized, the condition of its movement was presented and the indicators determining the active safety of the moving vehicle were determined. The characteristics of the full power of internal combustion engines with spark ignition and the vehicle traction diagram were analyzed and compared. Then, on the basis of the performed analyzes, the conditions have been defined which must be met in order to be able to recognize that the vehicle is moving safely.

Improved lubrication parameters of lubricating oils due to the addition of carbon nanotubes (CNT) have been demonstrated in the past. This benefit, however, is short-lived due to self-induced re-agglomeration of CNTs in large concentrations in the oil. In this work the authors investigate the friction effects at trace amounts of CNT (as low as 0.03%). At such level the re-agglomeration effects are efficiently suppressed. Surprisingly, at such extreme low CNT concentration levels, a relatively large engine friction reduction of 6% was still observed. Moreover, a very strong vibration reduction of up to 30% was measured in the fired engine test. Full understanding of these results will require extensions/revisions of the existing models, which will pave the way to a new class of improved lubricants.

The possibilities of the vibration accelerations signals parameters application for the assessment of thermodynamic processes in the turbojet engine of the F-16 airplane given in its real work conditions have been presented in the paper. The aim is early detection of negative changes in the mixture formation and combustion processes taking place at the aircraft turbojet engine to maintain the high overall efficiency and safety of aviation tasks. Diagnostics of combustion and injection processes have been conducted for stationary engine investigations in the way to obtain quantity measures (dimensional and non-dimensional) and characteristics for these phenomena in the process value domain. The quality of the fuel injection and combustion, expressed in engine operation parameters of the best sensitivity, has been linked to the particular vibration impulse and energy representations, giving the important functional relations for building a diagnostic system for turbojet F-16 airplane engines for real operating conditions. The results show the proposed method assures early and accurate diagnostics for engine dynamic characteristics, making possible diagnostic system application. The diagnostic system design for combustion and injection processes monitoring and malfunctions detections has been proposed.

The issues of monitoring the processes of combustion and fuel injection in a turbojet engine of a multi-purpose aircraft in real conditions of its use with the use of selected characteristics and measures of acoustic signal processes have been described in the paper. The aim is early detection of sources and parametric assessment of the intensity of negative changes in the above-mentioned main processes and in the components of the aircraft propulsion system, taking into account contemporary criteria for improving the safety of the implementation of the aviation task. Appropriate functional relations have been built for acoustic characteristics that are a response to specific sources of changes in the creation of a combustible mixture and its combustion process, which can be used in their continuous diagnostics, in accordance with the criteria of the highest operational efficiency of the thermodynamic and mechatronic system, including ensuring safety improvement. Operational indicators of the highest sensitivity for both processes have been linked to the particular acoustic impulse and energy parameters and frequency spectra, for which specified energy quantum is transferred by means of vibrating particles. The results demonstrate the proposed method assures early and accurate diagnostics for engine dynamic characteristics. The built procedures for combustion and injection projections in the acoustic discrete and continuous representations, both in process value and frequency domains, make the obtained findings valid for on-board fault-diagnosis system building.