Geometry and material
Flywheels are dimensionally designed on the basis of the following non-exhaustive data:
- Gearbox housing shell
- Crankshaft nose dimensions
- Clutch geometry
- Maximum engine speed
- Acyclism data
- Clutch friction strength
- Tightening torque of the crankshaft mounting bolts
- Working temperatures
- ….
We carry out computer-aided drafting work based on the above data in order to fulfil the dimensional and inertia requirements, then conduct the finite-element analyses to pre-validate the design and determine the material before prototypes are made.
Depending on the calculated stresses, the following materials can be used:
- Grey iron (200 to 300 MPa)
- Compacted graphite iron (300 to 500 MPa)
- Ductile cast iron (400 to 700 MPa)
- Steel (over 700 MPa)
Validation
Flywheel, starter motor ring gear and inertia ring design is validated on our test benches:
- Centrifuging
- Engine running
- Force test bench for clutch thrust and acyclism
- Starter motor ring gear separation bench
- …
And in an anechoic chamber to assess starting and running noises.
