1. Powertrain solid-body motion (GMP)

1.1 Perfectly balanced GMP solid body movements

We're interested here in the motions of the drive train (figure 1 ) under the effect of the forces and moments induced by the motion of the moving linkage (pistons, piston pins, connecting rods in part) and by the gas pressure in the cylinders up to around 100 Hz. It is assumed that engine speed variations are sufficiently slow to maintain the hypothesis of periodic operation. The advantage of this assumption is that it places us in the frequency domain, which is particularly well-suited to acoustics.