vibratory characterization (nodal analysis) of a diesel engine Mercedes 220D with and without Pantone system Testing of the 5 7 2007 March toIUT de Roanne Analysis in the Laboratory of Signals and Industrial Process.
Accélérométries three sensors are placed on the cylinder head screws. They are located respectively above the cylinders 1, 2 and 4. A fourth accelerometer is placed on a rib of the engine block facing the cylinder 1. Finally, an inductive sensor is attached at the starting ring.
Processing signals from the inductive sensor
From the inductive sensor signal, we estimate the instantaneous rotational speed of the motor shaft.
Re we are sampling the speed in the angular domain and calculate the average to the synchronous motor cycle representative of the average speed variations in the cycle.
If we observe little difference at the first peak corresponding to the damage from the 1 combustion cylinder, However there is an almost total disappearance of the second peak may correspond to shocks produced by tilting the piston. This phenomenon also seems to occur at the same 2 cylinder is much less obvious.