BLDC Fan RPM vs. PWM Duty Cycle

A simpleminded MOSFET circuit provides PWM drive for the BLDC blower:

The Tek P6302 current probe looms much larger in real life than in the schematic:

A quick dataset shows the RPM variation against PWM duty cycle:

Unsurprisingly, the RPM curve resembles the earlier results against a variable DC supply voltage:

Capturing the current waveform is stalled behind another project, but it has exactly the voltage spikes you’d expect from forcibly switching an inductive load.