Let me say at the outset, I'm not trying to sell them.
Pretty much all of engineering in UK is in SI units. I'd have to use them whether I like them or not. But I do think they have merit. I'll try to explain why with an example that I posted in another thread.
The first three lines are the known data.
The 156.5 is the conversion from revs per minute to radians per second.
This is probably the most complex part of the process.
There are 2*pi radians in a revolution and 60 seconds in a minute.
Thus we get 1494*2*pi/60 = 156.451. Which is usually referenced as ω
So not really very complex at all.
Next, power is speed times torque.
P = Tω (Power in Watts)
So
T = P/ω
Or 6630e3/156.451 = 42,377
Next, acceleration (α) is torque divided by inertia.
So
α = T/I
Or 42,377/378 = 112.1
And finally
Acceleration time is given by speed divided by accel rate.
156.5/112.1 = 1.4
Other than knowing how to convert RPM into rad/s using the universal constant pi, a widely known value and on most calculators, there are no conversion factors.
Being just multiplication and division of numbers, the arithmetic is simple.
And I like simple.
Pretty much all of engineering in UK is in SI units. I'd have to use them whether I like them or not. But I do think they have merit. I'll try to explain why with an example that I posted in another thread.
The first three lines are the known data.
The 156.5 is the conversion from revs per minute to radians per second.
This is probably the most complex part of the process.
There are 2*pi radians in a revolution and 60 seconds in a minute.
Thus we get 1494*2*pi/60 = 156.451. Which is usually referenced as ω
So not really very complex at all.
Next, power is speed times torque.
P = Tω (Power in Watts)
So
T = P/ω
Or 6630e3/156.451 = 42,377
Next, acceleration (α) is torque divided by inertia.
So
α = T/I
Or 42,377/378 = 112.1
And finally
Acceleration time is given by speed divided by accel rate.
156.5/112.1 = 1.4
Other than knowing how to convert RPM into rad/s using the universal constant pi, a widely known value and on most calculators, there are no conversion factors.
Being just multiplication and division of numbers, the arithmetic is simple.
And I like simple.