Make dealing with units in PyRolL easier

[GRPlan]

In PyRolL there is the convention that SI-Units are to be used. E.g. length in meters, temperatures in Kelvin.

To convert units more easily I use a dictionary that contains the conversion factors.

convert_SI = {
'length': 1.e-3,
'stress': 1.e6,
'density': 1.e12,
'cp': 1.e-6,
'temperature': 273.15,
'frequency': 1./60,
}

convert_SI['area'] = convert_SI['length']**2
convert_SI['volume'] = convert_SI['length']**3

When you prepare PyRolL input then you just need to multiply (or add) by the convert_SI and provide the appropriate key

E.g.

InDiameter = 71.
StartTemperature = 1000.

Rod = pr.Profile.round(diameter=InDiameter * convert_SI['length'], **MatProps)

Rod.temperature = StartTemperature + convert_SI['temperature']

When you retrieve data from PyRolL results conversion can be done by dividing (subtracting)

E.g.

for rollpass in Rollpass.roll_passes:
print(rollpass.label, rollpass.strain_rate, rollpass.roll.rotational_frequency / convert_SI['frequency'])

Used in Examplenotebook #205

[sag-kalibreur]

Very good and reusable solution Geralt. Thanks for sharing. @ChRen95, @axtimhaus: In the future, the calculation of the units in mm and degrees celsius should be integrated directly into the core. This will make it much more user friendly for users.

[ChRen95]

@axtimhaus and myself are currently thinking of a way to integrate unit handling.
Still we haven't concluded. We'll keep you updated.