Inertia
*Drawing from Theory of ground vehicles, 2nd ed., J.Y. Wong, 1993, p. 169 (modified)
Theory (more)
Theory
Vehicle mass (more)
Knowing the engine size (Veng) in liters, the vehicle mass (mv) can be estimated with equation (1):
|
(1) |
Where Cm depends on the vehicle type, as in the following table:
| Vehicle type | Cm |
| Race car | 0.32 |
| Motorcycle | 0.35 |
| Race car (production model) | 0.55 |
| Sport car (2-seat) | 0.85 |
| Passenger car | 1.00 |
| Luxury car | 1.10 |
Mass factor (more)
The mass factor (λm) is the relationship between the total mass of the vehicle (mv) and the effective mass (me) of the vehicle, if we take into account the effect of the inertia of the rotating parts on the vehicle acceleration characteristics, such that:
|
(2) |
Where Fnet is the net thrust acting on the vehicle and a is its acceleration.
From Theory of ground vehicles (2nd ed., p. 211), for passenger cars, an empirical relationship can relate the mass factor with the overall gear ratio (G):
|
(3) |