Present paper aims to validate a simulation model through experimental research in order to determine fuel consumption of a vehicle. To this purpose, the experimental test consisted in the usage of a specialized tester in order to record several parameters characteristic to vehicle and engine functioning. Specific data were subsequently used to determine real fuel consumption. To perform a comparative analysis, the theoretical fuel consumption was determined with the use of data acquired during experimental tests and simulated graphical software.

The present paper aims to analyze the influence of certain parameters specific to the distribution systems on a truck engine performance. The research is focused on how the change in the shape of lobes of a camshaft can influence the vehicle functional parameters. It was considered a non-variable fuel distribution system which represents by itself the controlling part, needed to move the poppet valves in order to ensure engine operating cycles. There have been compared results obtained in the case of different profiles of lobes, taking into account the accelerations during movements, in order to obtain minimum inertia of the distribution system components. By increasing the total height of the lobes, it was observed an increase in engine power and torque. Also, the intake air efficiency was improved by approximately 4%. Furthermore, engine fuel consumption reached higher levels in the case of the modified camshaft, in order to increase engine power.

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The present paper aims to analyse the possibility to prevent machine failure due to bearing faults, with the use of frequency analysis. The experimental research consisted in mounting a simple mechanical transmission, integrating an electric motor, a rigid coupling, a driven shaft, two pillow block bearings and a uniaxial accelerometer (connected to a data acquisition board), which was tested at two constant motor speeds. Follow-up, with the use of recorded data, it was plotted the envelope spectrum of bearing functioning, based on BPFO, BPFI, FTF and BSF harmonics, which were later used to determine on which element of the bearing is the defect located, or if the bearing lacks proper greasing.

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