Coaxial motor setup?


#1

Hi everyone brand new on the forum, i am curious if any one has run a coaxial motor setup on their rov and what would be the loss compare to two motor side by side


#2

In theory at least, the thrust loss will be quite considerable as you are effectively doubling the disk loading of the thruster. This set of static thrust calculations is for an open rotor operating in air but the same applies to water. The calculations are a bit different for a shrouded rotor or ROV thruster (I think the exponent is 2/3, rather than 1/3). I’ll upload them if I ever get time to go through the derivation again.

Perhaps somebody else has the calculations for a ducted rotor and some comments about how well the theory applies to ROVs thrusters in practical terms.

Sam


#3

I based the expected efficiency loss on coaxial quadcopter, but the number have a very high range from 30 percent efficiency loss to as low as 10 percent. One question, what if i duct the motor in this way so that each motor has its own flow, separate from the each other.