Any discussion of HP and torque in motors has to take into account time. That is, during each revolution of the motor, is the force applied an impulse as in the ICE's piston just after detonation, or more continuously as in electro-magnetic motors. If you want to compare the two systems fairly, the cumulative amount of time while generating propulsion is that much higher in a multi-pole electric motor. And that is why ICE motors need a flywheel to maintain torque once the detonation is complete. Ratings are not universal.
--- In electricboats@
>
> With the recent hp equivalency discussion I was wondering if you
> could use torque as a valid measure. For example in my case could you just
> look at the torque curve for a Yanmar 2GM20, find out how much torque there
> is at about 2800 RPM or so (cruising speed), then take that value and find
> an electric motor with the same torque at whatever you're going to use for
> cruising RPM? I guess you might be able to bias it a little bit toward a
> smaller electric motor since I do plan on using a bigger, slower turning
> propeller than on the diesel installation. Any thoughts?
>
> Thanks,
>
> Jerry Barth
>
>
>
> [Non-text portions of this message have been removed]
>
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