I'm doing a project for thermodynamics where I have to measure the power (work over time) of a Stirling engine for varying temperature differences. I don't necessarily need an exact answer (as in: ... Watt), but a "relative" measurement would also work (i.e. when the temperature difference between the hot end and the cold end is doubled, the work increases by a factor of ...).
I've thought of filming the engine run in slow-mo, and then using the RPM of the Stirling engine to calculate power, but I could not quite work out how to do this.
Any suggestions? Thanks in advance!